Hearing Aid Startup to Receive $45 Million Funding

​Eargo (https://eargo.com/), a direct-to-consumer hearing technology company, has announced the closing of the first tranche of an aggregate $45 million Series C investment round, which the company said will be used to accelerate their product innovation. The new investment was led by Nan Fung Life Sciences. New Enterprise Associates, Charles and Helen Schwab, and Maveron have also provided investments. Eargo is designed for consumers with on-the-go lifestyles and the desire for simplicity. Christian Gormsen, the CEO of Eargo, said, "We believe people shouldn't feel that they need a hearing aid.  They should feel that they want one.  Eargo was created with this in mind and we're just getting started."​

Published: 10/27/2017 2:07:00 PM

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Hearing Aid Startup to Receive $45 Million Funding

​Eargo (https://eargo.com/), a direct-to-consumer hearing technology company, has announced the closing of the first tranche of an aggregate $45 million Series C investment round, which the company said will be used to accelerate their product innovation. The new investment was led by Nan Fung Life Sciences. New Enterprise Associates, Charles and Helen Schwab, and Maveron have also provided investments. Eargo is designed for consumers with on-the-go lifestyles and the desire for simplicity. Christian Gormsen, the CEO of Eargo, said, "We believe people shouldn't feel that they need a hearing aid.  They should feel that they want one.  Eargo was created with this in mind and we're just getting started."​

Published: 10/27/2017 2:07:00 PM

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Hearing Aid Startup to Receive $45 Million Funding

​Eargo (https://eargo.com/), a direct-to-consumer hearing technology company, has announced the closing of the first tranche of an aggregate $45 million Series C investment round, which the company said will be used to accelerate their product innovation. The new investment was led by Nan Fung Life Sciences. New Enterprise Associates, Charles and Helen Schwab, and Maveron have also provided investments. Eargo is designed for consumers with on-the-go lifestyles and the desire for simplicity. Christian Gormsen, the CEO of Eargo, said, "We believe people shouldn't feel that they need a hearing aid.  They should feel that they want one.  Eargo was created with this in mind and we're just getting started."​

Published: 10/27/2017 2:07:00 PM

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Modelling firing regularity in the ventral cochlear nucleus: Mechanisms, and effects of stimulus level and synaptopathy

Publication date: Available online 20 September 2017
Source:Hearing Research
Author(s): Dan F.M. Goodman, Ian M. Winter, Agnès C. Léger, Alain de Cheveigné, Christian Lorenzi
The auditory system processes temporal information at multiple scales, and disruptions to this temporal processing may lead to deficits in auditory tasks such as detecting and discriminating sounds in a noisy environment. Here, a modelling approach is used to study the temporal regularity of firing by chopper cells in the ventral cochlear nucleus, in both the normal and impaired auditory system. Chopper cells, which have a strikingly regular firing response, divide into two classes, sustained and transient, based on the time course of this regularity. Several hypotheses have been proposed to explain the behaviour of chopper cells, and the difference between sustained and transient cells in particular. However, there is no conclusive evidence so far. Here, a reduced mathematical model is developed and used to compare and test a wide range of hypotheses with a limited number of parameters. Simulation results show a continuum of cell types and behaviours: chopper-like behaviour arises for a wide range of parameters, suggesting that multiple mechanisms may underlie this behaviour. The model accounts for systematic trends in regularity as a function of stimulus level that have previously only been reported anecdotally. Finally, the model is used to predict the effects of a reduction in the number of auditory nerve fibres (deafferentation due to, for example, cochlear synaptopathy). An interactive version of this paper in which all the model parameters can be changed is available online.

Graphical abstract

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Modelling firing regularity in the ventral cochlear nucleus: Mechanisms, and effects of stimulus level and synaptopathy

Publication date: Available online 20 September 2017
Source:Hearing Research
Author(s): Dan F.M. Goodman, Ian M. Winter, Agnès C. Léger, Alain de Cheveigné, Christian Lorenzi
The auditory system processes temporal information at multiple scales, and disruptions to this temporal processing may lead to deficits in auditory tasks such as detecting and discriminating sounds in a noisy environment. Here, a modelling approach is used to study the temporal regularity of firing by chopper cells in the ventral cochlear nucleus, in both the normal and impaired auditory system. Chopper cells, which have a strikingly regular firing response, divide into two classes, sustained and transient, based on the time course of this regularity. Several hypotheses have been proposed to explain the behaviour of chopper cells, and the difference between sustained and transient cells in particular. However, there is no conclusive evidence so far. Here, a reduced mathematical model is developed and used to compare and test a wide range of hypotheses with a limited number of parameters. Simulation results show a continuum of cell types and behaviours: chopper-like behaviour arises for a wide range of parameters, suggesting that multiple mechanisms may underlie this behaviour. The model accounts for systematic trends in regularity as a function of stimulus level that have previously only been reported anecdotally. Finally, the model is used to predict the effects of a reduction in the number of auditory nerve fibres (deafferentation due to, for example, cochlear synaptopathy). An interactive version of this paper in which all the model parameters can be changed is available online.

Graphical abstract

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The Analysis of A Frequent TMPRSS3 Allele Containing P.V116M and P.V291L in A Cis Configuration among Deaf Koreans.

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The Analysis of A Frequent TMPRSS3 Allele Containing P.V116M and P.V291L in A Cis Configuration among Deaf Koreans.

Int J Mol Sci. 2017 Oct 26;18(11):

Authors: Kim AR, Chung J, Kim NKD, Lee C, Park WY, Oh DY, Choi BY

Abstract
We performed targeted re-sequencing to identify the genetic etiology of early-onset postlingual deafness and encountered a frequent TMPRSS3 allele harboring two variants in a cis configuration. We aimed to evaluate the pathogenicity of the allele. Among 88 cochlear implantees with autosomal recessive non-syndromic hearing loss, subjects with GJB2 and SLC26A4 mutations were excluded. Thirty-one probands manifesting early-onset postlingual deafness were sorted. Through targeted re-sequencing, we detected two families with a TMPRSS3 mutant allele containing p.V116M and p.V291L in a cis configuration, p.[p.V116M; p.V291L]. A minor allele frequency was calculated and proteolytic activity was measured. A p.[p.V116M; p.V291L] allele demonstrated a significantly higher frequency compared to normal controls and merited attention due to its high frequency (4.84%, 3/62). The first family showed a novel deleterious splice site variant-c.783-1G>A-in a trans allele, while the other showed homozygosity. The progression to deafness was noted within the first decade, suggesting DFNB10. The proteolytic activity was significantly reduced, confirming the severe pathogenicity. This frequent mutant allele significantly contributes to early-onset postlingual deafness in Koreans. For clinical implication and proper auditory rehabilitation, it is important to pay attention to this allele with a severe pathogenic potential.

PMID: 29072634 [PubMed - in process]

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Implications of using the Hearing Aids on quality of life of elderly.

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Implications of using the Hearing Aids on quality of life of elderly.

Codas. 2017 Oct 19;29(5):e20160241

Authors: Carniel CZ, Sousa JCF, Silva CDD, Fortunato-Queiroz CAU, Hyppolito MÂ, Santos PLD

Abstract
PURPOSE: To evaluate through standardized questionnaires the quality of life of elderly people with hearing loss diagnosed with and without the use of hearing aids (HA) and elderly without hearing complaints.
METHODS: This is a cross-sectional study with non probabilistic sample, divided into three groups divided as follows: 30 elderly people with diagnosed hearing loss and indication for use of individual sound amplification devices (hearing aids), but have not yet made use of the prosthesis; 30 individuals with hearing impairment who used hearing aids and 30 elderly without hearing complaints. Participants completed a questionnaire investigating sociodemographic and family data, the Hearing Handicap Inventory for the Elderly Screening Version (HHIE-S) and the World Health Organization Quality of Life - Short version (WHOQOL-BREF). In addition to the descriptive analysis of the data were performed tests to compare the three groups by applying analysis of variance (ANOVA) and the Bonferroni post hoc test.
RESULTS: The three groups differed significantly in all domains of quality of life. The group of the elderly people with hearing loss diagnosed and with indication for the use of hearing aids presented lower scores and the group of the elderly with hearing disabilities that used the hearing aid and that the reference group. The AASI group presented the best quality of life results.
CONCLUSION: The hearing loss affects the quality of life of the elderly. The effective use of hearing aid is beneficial to this population, improving their living and health conditions.

PMID: 29069166 [PubMed - in process]

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The use of the Frequency Modulation System by hearing-impaired children: benefits from the family's perspective.

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The use of the Frequency Modulation System by hearing-impaired children: benefits from the family's perspective.

Codas. 2017 Oct 19;29(6):e20160236

Authors: Rocha BDS, Scharlach RC

Abstract
PURPOSE: To evaluate the family's perspective of benefits of the frequency modulation (FM) system adapted to children with sensorineural hearing loss.
METHODS: This is a descriptive, analytical, cross-sectional study with the participation of family members of hearing-impaired children aged 6 to 15 years, users of hearing aids and/or cochlear implants, benefited with the FM system by a hearing health service of the Unified Health System (SUS), Brazil. The FM Listening Evaluation For Children questionnaire with 14 questions was used to evaluate the benefits of using the FM system, the characteristics of the hearing aids and/or cochlear implants, and the brand/model of the FM system the children used.
RESULTS: Statistically significant differences were found between the questionnaire responses of FM users and non-users in all situational analyses (quiet, noise, auditory only, distance), with better learning performance and improvements and attention among FM users, from the families' point of view. No method was used to formally evaluate such performances.
CONCLUSION: It was observed that, according to the parents' and guardians' perceptions, the use of FM systems improves the performance of hearing-impaired children in various acoustic situations, with special emphasis on speech recognition in noisy environments and at increased distances from the sound source. Although used in different contexts and situations, the FM system has brought greater benefits for the children in the school environment, according to the respondents.

PMID: 29069130 [PubMed - in process]

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A de novo mutation in RPL10 causes a rare X-linked ribosomopathy characterized by syndromic intellectual disability and epilepsy: A new case and review of the literature.

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A de novo mutation in RPL10 causes a rare X-linked ribosomopathy characterized by syndromic intellectual disability and epilepsy: A new case and review of the literature.

Eur J Med Genet. 2017 Oct 21;:

Authors: Bourque DK, Hartley T, Nikkel SM, Pohl D, Tétreault M, Kernohan KD, Care4Rare Canada Consortium, Dyment DA

Abstract
Intellectual disability (ID) affects 1-2% of the general population and up to 50% of those with ID are estimated to have an underlying genetic cause. Next-generation sequencing provides an efficient means to identify the molecular causes of monogenic forms of ID. Here we present an 18 year old male with severe ID, absent speech, microcephaly, ataxia, dysmorphic facial features, and a refractory, early-onset seizure disorder. Exome sequencing revealed a rare de novo mutation in the X-linked gene RPL10 (c.232A > G, p.K78E). Previous reports of inherited mutations in the RPL10 gene have suggested a role for the gene in neurodevelopment and the individual reported shows marked similarities to three members of a family with the same mutation reported in the literature. The p.K78E substitution appears to be associated with severe microcephaly, seizures, hearing loss, growth retardation, cardiac defects, and dysmorphic facial features. This is the first instance that a de novo mutation in RPL10 has been reported.

PMID: 29066376 [PubMed - as supplied by publisher]

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NLRP3 Is Expressed in the Spiral Ganglion Neurons and Associated with Both Syndromic and Nonsyndromic Sensorineural Deafness.

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NLRP3 Is Expressed in the Spiral Ganglion Neurons and Associated with Both Syndromic and Nonsyndromic Sensorineural Deafness.

Neural Plast. 2016;2016:3018132

Authors: Chen P, He L, Pang X, Wang X, Yang T, Wu H

Abstract
Nonsyndromic deafness is genetically heterogeneous but phenotypically similar among many cases. Though a variety of targeted next-generation sequencing (NGS) panels has been recently developed to facilitate genetic screening of nonsyndromic deafness, some syndromic deafness genes outside the panels may lead to clinical phenotypes similar to nonsyndromic deafness. In this study, we performed comprehensive genetic screening in a dominant family in which the proband was initially diagnosed with nonsyndromic deafness. No pathogenic mutation was identified by targeted NGS in 72 nonsyndromic and another 72 syndromic deafness genes. Whole exome sequencing, however, identified a p.E313K mutation in NLRP3, a gene reported to cause syndromic deafness Muckle-Wells Syndrome (MWS) but not included in any targeted NGS panels for deafness in previous reports. Follow-up clinical evaluation revealed only minor inflammatory symptoms in addition to deafness in six of the nine affected members, while the rest, three affected members, including the proband had no obvious MWS-related inflammatory symptoms. Immunostaining of the mouse cochlea showed a strong expression of NLRP3 in the spiral ganglion neurons. Our results suggested that NLRP3 may have specific function in the spiral ganglion neurons and can be associated with both syndromic and nonsyndromic sensorineural deafness.

PMID: 27965898 [PubMed - indexed for MEDLINE]

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Aftereffects of Intense Low-Frequency Sound on Spontaneous Otoacoustic Emissions: Effect of Frequency and Level.

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Aftereffects of Intense Low-Frequency Sound on Spontaneous Otoacoustic Emissions: Effect of Frequency and Level.

J Assoc Res Otolaryngol. 2017 Feb;18(1):111-119

Authors: Jeanson L, Wiegrebe L, Gürkov R, Krause E, Drexl M

Abstract
The presentation of intense, low-frequency (LF) sound to the human ear can cause very slow, sinusoidal oscillations of cochlear sensitivity after LF sound offset, coined the "Bounce" phenomenon. Changes in level and frequency of spontaneous otoacoustic emissions (SOAEs) are a sensitive measure of the Bounce. Here, we investigated the effect of LF sound level and frequency on the Bounce. Specifically, the level of SOAEs was tracked for minutes before and after a 90-s LF sound exposure. Trials were carried out with several LF sound levels (93 to 108 dB SPL corresponding to 47 to 75 phons at a fixed frequency of 30 Hz) and different LF sound frequencies (30, 60, 120, 240 and 480 Hz at a fixed loudness level of 80 phons). At an LF sound frequency of 30 Hz, a minimal sound level of 102 dB SPL (64 phons) was sufficient to elicit a significant Bounce. In some subjects, however, 93 dB SPL (47 phons), the lowest level used, was sufficient to elicit the Bounce phenomenon and actual thresholds could have been even lower. Measurements with different LF sound frequencies showed a mild reduction of the Bounce phenomenon with increasing LF sound frequency. This indicates that the strength of the Bounce not only is a simple function of the spectral separation between SOAE and LF sound frequency but also depends on absolute LF sound frequency, possibly related to the magnitude of the AC component of the outer hair cell receptor potential.

PMID: 27761740 [PubMed - indexed for MEDLINE]

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Aftereffects of Intense Low-Frequency Sound on Spontaneous Otoacoustic Emissions: Effect of Frequency and Level.

Related Articles

Aftereffects of Intense Low-Frequency Sound on Spontaneous Otoacoustic Emissions: Effect of Frequency and Level.

J Assoc Res Otolaryngol. 2017 Feb;18(1):111-119

Authors: Jeanson L, Wiegrebe L, Gürkov R, Krause E, Drexl M

Abstract
The presentation of intense, low-frequency (LF) sound to the human ear can cause very slow, sinusoidal oscillations of cochlear sensitivity after LF sound offset, coined the "Bounce" phenomenon. Changes in level and frequency of spontaneous otoacoustic emissions (SOAEs) are a sensitive measure of the Bounce. Here, we investigated the effect of LF sound level and frequency on the Bounce. Specifically, the level of SOAEs was tracked for minutes before and after a 90-s LF sound exposure. Trials were carried out with several LF sound levels (93 to 108 dB SPL corresponding to 47 to 75 phons at a fixed frequency of 30 Hz) and different LF sound frequencies (30, 60, 120, 240 and 480 Hz at a fixed loudness level of 80 phons). At an LF sound frequency of 30 Hz, a minimal sound level of 102 dB SPL (64 phons) was sufficient to elicit a significant Bounce. In some subjects, however, 93 dB SPL (47 phons), the lowest level used, was sufficient to elicit the Bounce phenomenon and actual thresholds could have been even lower. Measurements with different LF sound frequencies showed a mild reduction of the Bounce phenomenon with increasing LF sound frequency. This indicates that the strength of the Bounce not only is a simple function of the spectral separation between SOAE and LF sound frequency but also depends on absolute LF sound frequency, possibly related to the magnitude of the AC component of the outer hair cell receptor potential.

PMID: 27761740 [PubMed - indexed for MEDLINE]

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The performance of an automatic acoustic-based program classifier compared to hearing aid users' manual selection of listening programs.

Related Articles

The performance of an automatic acoustic-based program classifier compared to hearing aid users' manual selection of listening programs.

Int J Audiol. 2017 Oct 25;:1-12

Authors: Searchfield GD, Linford T, Kobayashi K, Crowhen D, Latzel M

Abstract
OBJECTIVE: To compare preference for and performance of manually selected programmes to an automatic sound classifier, the Phonak AutoSense OS.
DESIGN: A single blind repeated measures study. Participants were fit with Phonak Virto V90 ITE aids; preferences for different listening programmes were compared across four different sound scenarios (speech in: quiet, noise, loud noise and a car). Following a 4-week trial preferences were reassessed and the users preferred programme was compared to the automatic classifier for sound quality and hearing in noise (HINT test) using a 12 loudspeaker array.
STUDY SAMPLE: Twenty-five participants with symmetrical moderate-severe sensorineural hearing loss.
RESULTS: Participant preferences of manual programme for scenarios varied considerably between and within sessions. A HINT Speech Reception Threshold (SRT) advantage was observed for the automatic classifier over participant's manual selection for speech in quiet, loud noise and car noise. Sound quality ratings were similar for both manual and automatic selections.
CONCLUSIONS: The use of a sound classifier is a viable alternative to manual programme selection.

PMID: 29069954 [PubMed - as supplied by publisher]

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Optimising the effect of noise reduction algorithm ClearVoice in cochlear implant users by increasing the maximum comfort levels.

Related Articles

Optimising the effect of noise reduction algorithm ClearVoice in cochlear implant users by increasing the maximum comfort levels.

Int J Audiol. 2017 Oct 24;:1-6

Authors: Dingemanse JG, Goedegebure A

Abstract
OBJECTIVE: ClearVoice is a single-microphone noise reduction algorithm in Advanced Bionics cochlear implant(CI) systems with the aim to improve performance in background noise. The present study investigated a hypothesised increased effect of ClearVoice if combined with a structural increase of maximum comfort stimulation levels (M-levels) in the CI fitting.
DESIGN: We tested performance with ClearVoice (Medium) in four conditions, defined by combined settings of ClearVoice off/on and with/without 5% increase of M-levels. The main outcome measures were the Acceptable Noise Level (ANL) and the speech reception threshold in continuous background noise (SRTn).
STUDY SAMPLE: Participants were 16 experienced cochlear implant recipients with Advanced Bionics implants and a Naida Q70 processor.
RESULTS: The ANL significantly improved by using either ClearVoice or an increase of M-levels. Combining both settings gave the largest improvement in ANL. For the SRTn, we found a small, but significant interaction between ClearVoice and an increase of M-levels, implying that ClearVoice improved speech understanding slightly, but only if combined with a 5% increase of M-levels.
CONCLUSIONS: Optimal profit from ClearVoice is obtained if combined with a structural 5% increase of M-levels.

PMID: 29065731 [PubMed - as supplied by publisher]

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The performance of an automatic acoustic-based program classifier compared to hearing aid users' manual selection of listening programs.

Related Articles

The performance of an automatic acoustic-based program classifier compared to hearing aid users' manual selection of listening programs.

Int J Audiol. 2017 Oct 25;:1-12

Authors: Searchfield GD, Linford T, Kobayashi K, Crowhen D, Latzel M

Abstract
OBJECTIVE: To compare preference for and performance of manually selected programmes to an automatic sound classifier, the Phonak AutoSense OS.
DESIGN: A single blind repeated measures study. Participants were fit with Phonak Virto V90 ITE aids; preferences for different listening programmes were compared across four different sound scenarios (speech in: quiet, noise, loud noise and a car). Following a 4-week trial preferences were reassessed and the users preferred programme was compared to the automatic classifier for sound quality and hearing in noise (HINT test) using a 12 loudspeaker array.
STUDY SAMPLE: Twenty-five participants with symmetrical moderate-severe sensorineural hearing loss.
RESULTS: Participant preferences of manual programme for scenarios varied considerably between and within sessions. A HINT Speech Reception Threshold (SRT) advantage was observed for the automatic classifier over participant's manual selection for speech in quiet, loud noise and car noise. Sound quality ratings were similar for both manual and automatic selections.
CONCLUSIONS: The use of a sound classifier is a viable alternative to manual programme selection.

PMID: 29069954 [PubMed - as supplied by publisher]

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Optimising the effect of noise reduction algorithm ClearVoice in cochlear implant users by increasing the maximum comfort levels.

Related Articles

Optimising the effect of noise reduction algorithm ClearVoice in cochlear implant users by increasing the maximum comfort levels.

Int J Audiol. 2017 Oct 24;:1-6

Authors: Dingemanse JG, Goedegebure A

Abstract
OBJECTIVE: ClearVoice is a single-microphone noise reduction algorithm in Advanced Bionics cochlear implant(CI) systems with the aim to improve performance in background noise. The present study investigated a hypothesised increased effect of ClearVoice if combined with a structural increase of maximum comfort stimulation levels (M-levels) in the CI fitting.
DESIGN: We tested performance with ClearVoice (Medium) in four conditions, defined by combined settings of ClearVoice off/on and with/without 5% increase of M-levels. The main outcome measures were the Acceptable Noise Level (ANL) and the speech reception threshold in continuous background noise (SRTn).
STUDY SAMPLE: Participants were 16 experienced cochlear implant recipients with Advanced Bionics implants and a Naida Q70 processor.
RESULTS: The ANL significantly improved by using either ClearVoice or an increase of M-levels. Combining both settings gave the largest improvement in ANL. For the SRTn, we found a small, but significant interaction between ClearVoice and an increase of M-levels, implying that ClearVoice improved speech understanding slightly, but only if combined with a 5% increase of M-levels.
CONCLUSIONS: Optimal profit from ClearVoice is obtained if combined with a structural 5% increase of M-levels.

PMID: 29065731 [PubMed - as supplied by publisher]

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The performance of an automatic acoustic-based program classifier compared to hearing aid users' manual selection of listening programs.

Related Articles

The performance of an automatic acoustic-based program classifier compared to hearing aid users' manual selection of listening programs.

Int J Audiol. 2017 Oct 25;:1-12

Authors: Searchfield GD, Linford T, Kobayashi K, Crowhen D, Latzel M

Abstract
OBJECTIVE: To compare preference for and performance of manually selected programmes to an automatic sound classifier, the Phonak AutoSense OS.
DESIGN: A single blind repeated measures study. Participants were fit with Phonak Virto V90 ITE aids; preferences for different listening programmes were compared across four different sound scenarios (speech in: quiet, noise, loud noise and a car). Following a 4-week trial preferences were reassessed and the users preferred programme was compared to the automatic classifier for sound quality and hearing in noise (HINT test) using a 12 loudspeaker array.
STUDY SAMPLE: Twenty-five participants with symmetrical moderate-severe sensorineural hearing loss.
RESULTS: Participant preferences of manual programme for scenarios varied considerably between and within sessions. A HINT Speech Reception Threshold (SRT) advantage was observed for the automatic classifier over participant's manual selection for speech in quiet, loud noise and car noise. Sound quality ratings were similar for both manual and automatic selections.
CONCLUSIONS: The use of a sound classifier is a viable alternative to manual programme selection.

PMID: 29069954 [PubMed - as supplied by publisher]

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Optimising the effect of noise reduction algorithm ClearVoice in cochlear implant users by increasing the maximum comfort levels.

Related Articles

Optimising the effect of noise reduction algorithm ClearVoice in cochlear implant users by increasing the maximum comfort levels.

Int J Audiol. 2017 Oct 24;:1-6

Authors: Dingemanse JG, Goedegebure A

Abstract
OBJECTIVE: ClearVoice is a single-microphone noise reduction algorithm in Advanced Bionics cochlear implant(CI) systems with the aim to improve performance in background noise. The present study investigated a hypothesised increased effect of ClearVoice if combined with a structural increase of maximum comfort stimulation levels (M-levels) in the CI fitting.
DESIGN: We tested performance with ClearVoice (Medium) in four conditions, defined by combined settings of ClearVoice off/on and with/without 5% increase of M-levels. The main outcome measures were the Acceptable Noise Level (ANL) and the speech reception threshold in continuous background noise (SRTn).
STUDY SAMPLE: Participants were 16 experienced cochlear implant recipients with Advanced Bionics implants and a Naida Q70 processor.
RESULTS: The ANL significantly improved by using either ClearVoice or an increase of M-levels. Combining both settings gave the largest improvement in ANL. For the SRTn, we found a small, but significant interaction between ClearVoice and an increase of M-levels, implying that ClearVoice improved speech understanding slightly, but only if combined with a 5% increase of M-levels.
CONCLUSIONS: Optimal profit from ClearVoice is obtained if combined with a structural 5% increase of M-levels.

PMID: 29065731 [PubMed - as supplied by publisher]

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The performance of an automatic acoustic-based program classifier compared to hearing aid users' manual selection of listening programs.

Related Articles

The performance of an automatic acoustic-based program classifier compared to hearing aid users' manual selection of listening programs.

Int J Audiol. 2017 Oct 25;:1-12

Authors: Searchfield GD, Linford T, Kobayashi K, Crowhen D, Latzel M

Abstract
OBJECTIVE: To compare preference for and performance of manually selected programmes to an automatic sound classifier, the Phonak AutoSense OS.
DESIGN: A single blind repeated measures study. Participants were fit with Phonak Virto V90 ITE aids; preferences for different listening programmes were compared across four different sound scenarios (speech in: quiet, noise, loud noise and a car). Following a 4-week trial preferences were reassessed and the users preferred programme was compared to the automatic classifier for sound quality and hearing in noise (HINT test) using a 12 loudspeaker array.
STUDY SAMPLE: Twenty-five participants with symmetrical moderate-severe sensorineural hearing loss.
RESULTS: Participant preferences of manual programme for scenarios varied considerably between and within sessions. A HINT Speech Reception Threshold (SRT) advantage was observed for the automatic classifier over participant's manual selection for speech in quiet, loud noise and car noise. Sound quality ratings were similar for both manual and automatic selections.
CONCLUSIONS: The use of a sound classifier is a viable alternative to manual programme selection.

PMID: 29069954 [PubMed - as supplied by publisher]

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Optimising the effect of noise reduction algorithm ClearVoice in cochlear implant users by increasing the maximum comfort levels.

Related Articles

Optimising the effect of noise reduction algorithm ClearVoice in cochlear implant users by increasing the maximum comfort levels.

Int J Audiol. 2017 Oct 24;:1-6

Authors: Dingemanse JG, Goedegebure A

Abstract
OBJECTIVE: ClearVoice is a single-microphone noise reduction algorithm in Advanced Bionics cochlear implant(CI) systems with the aim to improve performance in background noise. The present study investigated a hypothesised increased effect of ClearVoice if combined with a structural increase of maximum comfort stimulation levels (M-levels) in the CI fitting.
DESIGN: We tested performance with ClearVoice (Medium) in four conditions, defined by combined settings of ClearVoice off/on and with/without 5% increase of M-levels. The main outcome measures were the Acceptable Noise Level (ANL) and the speech reception threshold in continuous background noise (SRTn).
STUDY SAMPLE: Participants were 16 experienced cochlear implant recipients with Advanced Bionics implants and a Naida Q70 processor.
RESULTS: The ANL significantly improved by using either ClearVoice or an increase of M-levels. Combining both settings gave the largest improvement in ANL. For the SRTn, we found a small, but significant interaction between ClearVoice and an increase of M-levels, implying that ClearVoice improved speech understanding slightly, but only if combined with a 5% increase of M-levels.
CONCLUSIONS: Optimal profit from ClearVoice is obtained if combined with a structural 5% increase of M-levels.

PMID: 29065731 [PubMed - as supplied by publisher]

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Combined Vocal Exercises for Rehabilitation After Supracricoid Laryngectomy: Evaluation of Different Execution Times

Publication date: Available online 27 October 2017
Source:Journal of Voice
Author(s): Hevely Saray Lima Silveira, Marcia Simões-Zenari, Marco Aurélio Kulcsar, Claudio Roberto Cernea, Kátia Nemr
IntroductionThe supracricoid partial laryngectomy allows the preservation of laryngeal functions with good local cancer control.ObjectiveTo assess laryngeal configuration and voice analysis data following the performance of a combination of two vocal exercises: the prolonged /b/vocal exercise combined with the vowel /e/ using chest and arm pushing with different durations among individuals who have undergone supracricoid laryngectomy.MethodsEleven patients undergoing partial laryngectomy supracricoid with cricohyoidoepiglottopexy (CHEP) were evaluated using voice recording. Four judges performed separately a perceptive-vocal analysis of hearing voices, with random samples. For the analysis of intrajudge reliability, repetitions of 70% of the voices were done. Intraclass correlation coefficient was used to analyze the reliability of the judges. For an analysis of each judge to the comparison between zero time (time point 0), after the first series of exercises (time point 1), after the second series (time point 2), after the third series (time point 3), after the fourth series (time point 4), and after the fifth and final series (time point 5), the Friedman test was used with a significance level of 5%. The data relative to the configuration of the larynx were subjected to a descriptive analysis.ResultsIn the evaluation, were considered the judge results 1 which have greater reliability. There was an improvement in the general level of vocal, roughness, and breathiness deviations from time point 4 [T4].ConclusionThe prolonged /b/vocal exercise, combined with the vowel /e/ using chest- and arm-pushing exercises, was associated with an improvement in the overall grade of vocal deviation, roughness, and breathiness starting at minute 4 among patients who had undergone supracricoid laryngectomy with CHEP reconstruction.



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Moving from laboratory to real life conditions: Influence on the assessment of variability and stability of gait

Publication date: Available online 26 October 2017
Source:Gait & Posture
Author(s): Paola Tamburini, Fabio Storm, Chris Buckley, Maria Cristina Bisi, Rita Stagni, Claudia Mazzà
The availability of wearable sensors allows shifting gait analysis from the traditional laboratory settings, to daily life conditions. However, limited knowledge is available about whether alterations associated to different testing environment (e.g. indoor or outdoor) and walking protocols (e.g. free or controlled), result from actual differences in the motor behaviour of the tested subjects or from the sensitivity to these changes of the indexes adopted for the assessment. In this context, it was hypothesized that testing environment and walking protocols would not modify motor control stability in the gait of young healthy adults, who have a mature and structured gait pattern, but rather the variability of their motor pattern.To test this hypothesis, data from trunk and shank inertial sensors were collected from 19 young healthy participants during four walking tasks in different environments (indoor and outdoor) and in both controlled (i.e. following a predefined straight path) and free conditions. Results confirmed what hypothesized: variability indexes (Standard deviation, Coefficient of variation and Poincaré plots) were significantly influenced by both environment and walking condition. Stability indexes (Harmonic ratio, Short term Lyapunov exponents, Recurrence quantification analysis and Sample entropy), on the contrary, did not highlight any change in the motor control.In conclusion, this study highlighted an influence of environment and testing condition on the assessment of specific characteristics of gait (i.e. variability and stability). In particular, for young healthy adults, both environment and testing condition affect gait variability indexes, whereas neither affect gait stability indexes.



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Biomechanics of the infant foot during the transition to independent walking: A narrative review

Publication date: January 2018
Source:Gait & Posture, Volume 59
Author(s): Carina Price, Stewart C. Morrison, Farina Hashmi, Jill Phethean, Christopher Nester
Recognising structural and functional development of the paediatric foot is fundamental to ensuring a strong theoretical framework for health professionals and scientists. The transition of an infant from sitting to walking takes approximately 9 months and is when the structures and function of the foot must respond to the challenges of bearing load; becoming increasingly more essential for locomotion. Literature pertaining to the phase of development was searched. A narrative approach synthesised the information from papers written in English, with non-symptomatic infant participants up to the development stage of independent walking or two years of age. A range of literature was identified documenting morphological, physiological, neuromuscular and biomechanical aspects of the infant within this phase of development. The progression of variable gait to a regular pattern is documented within a range of studies focusing on neuromuscular control and ambulation development. However, methodological approaches may have compromised the external validity of such data. Additionally, limited consideration for the specific function and development of the foot is evident, despite its role as the primary site of weight bearing and interface with the floor. A lack of consideration of infants prior to ambulation (i.e. before cruising or walking) is also apparent which prevents a reference baseline being used effectively. This review also identifies future research priorities such that a comprehensive understanding of foot development from a non-weight bearing to a weight bearing structure during locomotor advancement can be gained.



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Contents List

Publication date: October 2017
Source:Gait & Posture, Volume 58





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Real-time visual biofeedback during weight bearing improves therapy compliance in patients following lower extremity fractures

Publication date: Available online 20 October 2017
Source:Gait & Posture
Author(s): Marco Raaben, Herman R. Holtslag, Luke P.H. Leenen, Robin Augustine, Taco J. Blokhuis
BackgroundIndividuals with lower extremity fractures are often instructed on how much weight to bear on the affected extremity. Previous studies have shown limited therapy compliance in weight bearing during rehabilitation. In this study we investigated the effect of real-time visual biofeedback on weight bearing in individuals with lower extremity fractures in two conditions: full weight bearing and touch-down weight bearing.Methods11 participants with full weight bearing and 12 participants with touch-down weight bearing after lower extremity fractures have been measured with an ambulatory biofeedback system. The participants first walked 15meters and the biofeedback system was only used to register the weight bearing. The same protocol was then repeated with real-time visual feedback during weight bearing. The participants could thereby adapt their loading to the desired level and improve therapy compliance.ResultsIn participants with full weight bearing, real-time visual biofeedback resulted in a significant increase in loading from 50.9±7.51% bodyweight (BW) without feedback to 63.2±6.74%BW with feedback (P=0.0016). In participants with touch-down weight bearing, the exerted lower extremity load decreased from 16.7±9.77kg without feedback to 10.27±4.56kg with feedback (P=0.0718). More important, the variance between individual steps significantly decreased after feedback (P=0.018).ConclusionsAmbulatory monitoring weight bearing after lower extremity fractures showed that therapy compliance is low, both in full and touch-down weight bearing. Real-time visual biofeedback resulted in significantly higher peak loads in full weight bearing and increased accuracy of individual steps in touch-down weight bearing. Real-time visual biofeedback therefore results in improved therapy compliance after lower extremity fractures.



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Camera pose estimation to improve accuracy and reliability of joint angles assessed with attitude and heading reference systems

Publication date: January 2018
Source:Gait & Posture, Volume 59
Author(s): Karina Lebel, Mathieu Hamel, Christian Duval, Hung Nguyen, Patrick Boissy
Joint kinematics can be assessed using orientation estimates from Attitude and Heading Reference Systems (AHRS). However, magnetically-perturbed environments affect the accuracy of the estimated orientations. This study investigates, both in controlled and human mobility conditions, a trial calibration technic based on a 2D photograph with a pose estimation algorithm to correct initial difference in AHRS Inertial reference frames and improve joint angle accuracy. In controlled conditions, two AHRS were solidly affixed onto a wooden stick and a series of static and dynamic trials were performed in varying environments. Mean accuracy of relative orientation between the two AHRS was improved from 24.4° to 2.9° using the proposed correction method. In human conditions, AHRS were placed on the shank and the foot of a participant who performed repeated trials of straight walking and walking while turning, varying the level of magnetic perturbation in the starting environment and the walking speed. Mean joint orientation accuracy went from 6.7° to 2.8° using the correction algorithm. The impact of starting environment was also greatly reduced, up to a point where one could consider it as non-significant from a clinical point of view (maximum mean difference went from 8° to 0.6°). The results obtained demonstrate that the proposed method improves significantly the mean accuracy of AHRS joint orientation estimations in magnetically-perturbed environments and can be implemented in post processing of AHRS data collected during biomechanical evaluation of motion.



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Influence of outdoor running fatigue and medial tibial stress syndrome on accelerometer-based loading and stability

Publication date: Available online 23 October 2017
Source:Gait & Posture
Author(s): Kurt H. Schütte, Stefan Seerden, Rachel Venter, Benedicte Vanwanseele
Medial tibial stress syndrome (MTSS) is a common overuse running injury with pathomechanics likely to be exaggerated by fatigue. Wearable accelerometry provides a novel alternative to assess biomechanical parameters continuously while running in more ecologically valid settings. The purpose of this study was to determine the influence of outdoor running fatigue and MTSS on both dynamic loading and dynamic stability derived from trunk and tibial accelerometery. Runners with (n=14) and without (n=16) history of MTSS performed an outdoor fatigue run of 3200m. Accelerometer-based measures averaged per lap included dynamic loading of the trunk and tibia (i.e. axial peak positive acceleration, signal power magnitude, and shock attenuation) as well as dynamic trunk stability (i.e. tri-axial root mean square ratio, step and stride regularity, and sample entropy). Regression coefficients from generalised estimating equations were used to evaluate group by fatigue interactions. No evidence could be found for dynamic loading being higher with fatigue in runners with MTSS history (all measures p>0.05). One significant group by running fatigue interaction effect was detected for dynamic stability. Specifically, in MTSS only, decreases mediolateral sample entropy i.e. loss of complexity was associated with running fatigue (p<0.01). The current results indicate that entire acceleration waveform signals reflecting mediolateral trunk control is related to MTSS history, a compensation that went undetected in the non-fatigued running state. We suggest that a practical outdoor running fatigue protocol that concurrently captures trunk accelerometry-based movement complexity warrants further prospective investigation as an in-situ screening tool for MTSS individuals.



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Real-World Walking in Multiple Sclerosis: Separating Capacity from Behavior

Publication date: Available online 16 October 2017
Source:Gait & Posture
Author(s): Matthew M. Engelhard, Stephen D. Patek, John C. Lach, Myla D. Goldman
BackgroundHabitual physical activity (HPA) measurement addresses the impact of MS on real-world walking, yet its interpretation is confounded by the competing influences of MS-associated walking capacity and physical activity behaviors.ObjectiveTo develop specific measures of MS-associated walking capacity through statistically sophisticated HPA analysis, thereby more precisely defining the real-world impact of disease.MethodsEighty-eight MS and 38 control subjects completed timed walks and patient-reported outcomes in clinic, then wore an accelerometer for 7 days. HPA was analyzed with several new statistics, including the maximum step rate (MSR) and habitual walking step rate (HWSR), along with conventional methods, including average daily steps. HPA statistics were validated using clinical walking outcomes.ResultsThe six-minute walk (6MW) step rate correlated most strongly with MSR (r=0.863, p<10⁻²⁵) and HWSR (r=0.815, p<10⁻¹¹) rather than average daily steps (r=0.676, p<10⁻¹¹). The combination of MSR and HWSR correlated more strongly with the 6MW step rate than either measure alone (r=0.884, p<10⁻¹⁴). The MSR overestimated the 6MW step rate (μ=10.4, p<10⁻⁷), whereas the HWSR underestimated it (μ=−18.2, p<10⁻¹⁹).ConclusionsConventional HPA statistics are poor measures of capacity due to variability in activity behaviors. The MSR and HWSR are valid, specific measures of real-world capacity which capture subjects’ highest step rate and preferred step rate, respectively.



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Analysis of data collected from right and left limbs: Accounting for dependence and improving statistical efficiency in musculoskeletal research

Publication date: January 2018
Source:Gait & Posture, Volume 59
Author(s): Sarah Stewart, Janet Pearson, Keith Rome, Nicola Dalbeth, Alain C. Vandal
ObjectivesStatistical techniques currently used in musculoskeletal research often inefficiently account for paired-limb measurements or the relationship between measurements taken from multiple regions within limbs. This study compared three commonly used analysis methods with a mixed-models approach that appropriately accounted for the association between limbs, regions, and trials and that utilised all information available from repeated trials.MethodFour analysis were applied to an existing data set containing plantar pressure data, which was collected for seven masked regions on right and left feet, over three trials, across three participant groups. Methods 1–3 averaged data over trials and analysed right foot data (Method 1), data from a randomly selected foot (Method 2), and averaged right and left foot data (Method 3). Method 4 used all available data in a mixed-effects regression that accounted for repeated measures taken for each foot, foot region and trial. Confidence interval widths for the mean differences between groups for each foot region were used as a criterion for comparison of statistical efficiency.ResultsMean differences in pressure between groups were similar across methods for each foot region, while the confidence interval widths were consistently smaller for Method 4. Method 4 also revealed significant between-group differences that were not detected by Methods 1–3.ConclusionA mixed effects linear model approach generates improved efficiency and power by producing more precise estimates compared to alternative approaches that discard information in the process of accounting for paired-limb measurements. This approach is recommended in generating more clinically sound and statistically efficient research outputs.



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Executive functioning, concern about falling and quadriceps strength mediate the relationship between impaired gait adaptability and fall risk in older people

Publication date: January 2018
Source:Gait & Posture, Volume 59
Author(s): Maria Joana D. Caetano, Stephen R. Lord, Matthew A. Brodie, Daniel Schoene, Paulo H.S. Pelicioni, Daina L. Sturnieks, Jasmine C. Menant
BackgroundReduced ability to adapt gait, particularly under challenging conditions, may be an important reason why older adults have an increased risk of falling. This study aimed to identify cognitive, psychological and physical mediators of the relationship between impaired gait adaptability and fall risk in older adults.MethodsFifty healthy older adults (mean±SD: 74±7years) were categorised as high or low fall risk, based on past falls and their performance in the Physiological Profile Assessment. High and low-risk groups were then compared in the gait adaptability test, i.e. an assessment of the ability to adapt gait in response to obstacles and stepping targets under single and dual task conditions. Quadriceps strength, concern about falling and executive function were also measured.ResultsThe older adults who made errors on the gait adaptability test were 4.76 (95%CI=1.08–20.91) times more likely to be at high risk of falling. Furthermore, each standard deviation reduction in gait speed while approaching the targets/obstacle increased the odds of being at high risk of falling approximately three fold: single task − OR=3.10,95%CI=1.43–6.73; dual task − 3.42,95%CI=1.56–7.52. Executive functioning, concern about falling and quadriceps strength substantially mediated the relationship between the gait adaptability measures and fall risk status.ConclusionImpaired gait adaptability is associated with high risk of falls in older adults. Reduced executive function, increased concern about falling and weaker quadriceps strength contribute significantly to this relationship. Training gait adaptability directly, as well as addressing the above mediators through cognitive, behavioural and physical training may maximise fall prevention efficacy.



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Prefrontal cortex activation during a dual task in patients with stroke

Publication date: January 2018
Source:Gait & Posture, Volume 59
Author(s): Takayuki Mori, Naoyuki Takeuchi, Shin-Ichi Izumi
Dual tasks destabilize task performance as they involve competing demands for cognitive and physical resources. Several studies have reported that dual-task walking activates the prefrontal cortex (PFC), and recent studies have indicated a relationship between PFC and dual-task deterioration in healthy subjects. However, PFC activity during dual-task walking in stroke patients remains unclear. We investigated the association between PFC activity and dual-task interference on physical and cognitive performance in stroke patients. This study included 14 stroke patients and 14 healthy subjects who performed a calculation task while walking at a comfortable pace on the floor. PFC activity was assessed using wearable near-infrared spectroscopy. The calculation task and trunk linear accelerations were evaluated as measures of cognitive and physical performance. The dual-task deterioration on both physical and cognitive performance of stroke patients was significantly higher than in healthy subjects. PFC activation during dual-task walking was significantly lower in stroke patients. Although right PFC activation was negatively correlated with dual-task deterioration on physical performance in stroke patients, left PFC activation was negatively correlated with the dual-task cost on cognitive performance in healthy subjects. Thus, during dual-task walking, PFC activation might prioritize physical demands in stroke patients, but might prioritize cognitive demands in healthy subjects.



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Automated event detection algorithm for two squatting protocols

Publication date: Available online 26 October 2017
Source:Gait & Posture
Author(s): Wilshaw R. Stevens, Alicia Y. Kokoszka, Anthony M. Anderson, Kirsten Tulchin-Francis
IntroductionSquatting biomechanics assessed using motion analysis relies on the identification of specific events: start of descent, transition between descent/ascent and end of ascent. Automated identification reduces the time needed to process trials while allowing consistency across studies. The purpose of this study was to develop criteria for the identification of events and apply them to two squatting protocols in pathological patient and typically developing (TD) groups.MethodsThirty-four subjects with hip dysplasia and forty-one TD subjects were enrolled in this study. While instrumented with a full-body Plug-In-Gait marker set, participants performed two squatting protocols: hold squat, where subjects paused for a count of three at their lowest squat depth, and traditional squat, where the descent phase was immediately followed by the ascent phase. Reviewers analyzed the kinematic/kinetic waveforms of a subset of trials to develop criteria for events. Sagittal plane knee and vertical center of mass velocities were used to identify events and absolute vs. relative thresholds of the peak knee velocity were compared. These criteria were incorporated into an automatic event detection code.ResultsUsing a relative threshold algorithm, events were automatically identified in 244 of 259 total trials (94%). For the trials requiring manual placement of events (n=15 trials), there was perfect inter-rater reliability between research personnel.ConclusionsThe criteria developed for the automatic detection of squatting events was highly successful for both protocols in each participant group and was also highly reliable for research personnel to follow in the few instances where manual placement was necessary.



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Imbalance: objective measures versus subjective self-report in clinical practice

Publication date: Available online 23 October 2017
Source:Gait & Posture
Author(s): Elodie Chiarovano, Wei Wang, Pam Reynolds, Hamish G. MacDougall
BackgroundDizziness and imbalance are very common complaints in clinical practice. One of the challenges is to evaluate the ‘real’ risk of falls. Two tools are available: the patient’s self-report and the measure of the patient’s balance. We evaluated the relationship between these methods using the Dizziness Handicap Inventory (DHI) and measures of balance while visual inputs are perturbed with Virtual Reality (VR).Methods90 consecutive patients underwent the DHI questionnaire and the balance test. The DHI questionnaire was used to measure the subject’s perception of handicap associated with dizziness. The balance test measured the postural sway in several visual conditions: eyes open, eyes closed, and with an unpredictable visual perturbation using VR at several amplitudes of movement.ResultsNo correlation was found between the DHI score and the balance measurement. The visual perturbations allow us to characterize patients into three groups: one group with a high DHI score who did not fall on the balance test (5.5%), one group with a low DHI score who failed eyes closed on a compliant surface (9.0%), and one group of the remaining patients (85.5%). The correlation between the DHI score and the balance performance became significant on the remaining group of patients.ConclusionBoth subjective self-report and objective measure are important to characterize a patient. The use of VR visual perturbations allowed us to define three important groups of patients. VR visual perturbations provided additional information that helps explain the lack of correlation between DHI and objective test results.



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Recovery of balance function among individuals with total knee arthroplasty: Comparison of responsiveness among four balance tests

Publication date: Available online 16 October 2017
Source:Gait & Posture
Author(s): Andy C.M. Chan, Xi H. Ouyang, Deborah A.M. Jehu, Raymond C.K. Chung, Marco Y.C. Pang
Background and aimBalance deficits are common after total knee arthroplasty (TKA); however the responsiveness of commonly used balance measurement tools has not been well defined. The objective of this prospective study was to compare the internal and external responsiveness of four measurement tools in assessing recovery of balance function following TKA.MethodsA total of 134 individuals with TKA (95 women; age: 66.3±6.6years) completed the Balance Evaluation Systems Test (BESTest), Mini-BESTest, Brief-BESTest, and Berg Balance Scale (BBS) at 2, 4, 8, 12, and 24 weeks post-TKA. The Functional Gait Assessment (FGA) served as the anchor measure, and was also measured across these time points. Internal responsiveness was indicated by the standardized response mean (SRM), while external responsiveness was reflected by the degree of association of the changes of balance scores with those of FGA.ResultsThe SRM ranged from 0.60–1.14 for the BESTest, 0.40–0.94 for the Mini-BESTest, 0.27–0.91 for the Brief-BESTest, and 0.19–0.70 for the BBS, over time. The change in BESTest and Mini-BESTest scores predicted the change in the FGA scores across all time periods, except for the Mini-BESTest between weeks 12–24, accounting for 13–27%, and 12–24% of the variance, respectively. The Brief-BESTest scores only predicted FGA scores between the weeks 2-4 (R²=20%). The changes in BBS scores were not associated with the FGA.ConclusionThe BESTest was the most responsive in measuring recovery of balance among individuals with TKA. The Mini-BESTest is a reasonable option during time constraints.



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Editorial Board

Publication date: October 2017
Source:Gait & Posture, Volume 58





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Analysis of biases in dynamic margins of stability introduced by the use of simplified center of mass estimates during walking and turning

Publication date: January 2018
Source:Gait & Posture, Volume 59
Author(s): Kathryn L. Havens, Tatri Mukherjee, James M. Finley
The ability to control the body’s center of mass (CoM) is critical for preventing falls, which are a major health concern in aging populations. Control of the CoM has been assessed by characterizing dynamic margins of stability (MoS) which capture the dynamic relationship between the CoM and the base of support. Accurate estimation of CoM dynamics is best accomplished using a full-body marker set. However, a number of simplified estimates have been used throughout literature. Here, we determined the biases and sources of bias when computing MoS using four simplified CoM models, and we characterized how these biases varied in straight walking versus turning. CoM kinematics were characterized using a full-body marker set, the lower extremities and trunk, lower extremities only, an average of four pelvic markers, and one pelvic marker alone. Significant bias was demonstrated for most methods and was larger during turning tasks compared to straight walking. In the fore-aft direction, only overestimates in the MoS were observed, and these ranged from 15 to 110% larger than the true MoS value. In the mediolateral direction, both under- and over-estimates were observed and ranged from −175 to 225%. Across tasks, bias was smallest when using the lower extremity plus trunk (−23 to 62%) and pelvis average methods (−71 to 43%). Sources of bias were attributed to misestimates of CoM height, velocity, and position. Together, our findings suggest that the 1) lower extremity and trunk model and 2) pelvis average model should be considered in future studies to minimize bias when simplified models of CoM dynamics are desired.



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Moving from laboratory to real life conditions: Influence on the assessment of variability and stability of gait

Publication date: Available online 26 October 2017
Source:Gait & Posture
Author(s): Paola Tamburini, Fabio Storm, Chris Buckley, Maria Cristina Bisi, Rita Stagni, Claudia Mazzà
The availability of wearable sensors allows shifting gait analysis from the traditional laboratory settings, to daily life conditions. However, limited knowledge is available about whether alterations associated to different testing environment (e.g. indoor or outdoor) and walking protocols (e.g. free or controlled), result from actual differences in the motor behaviour of the tested subjects or from the sensitivity to these changes of the indexes adopted for the assessment. In this context, it was hypothesized that testing environment and walking protocols would not modify motor control stability in the gait of young healthy adults, who have a mature and structured gait pattern, but rather the variability of their motor pattern.To test this hypothesis, data from trunk and shank inertial sensors were collected from 19 young healthy participants during four walking tasks in different environments (indoor and outdoor) and in both controlled (i.e. following a predefined straight path) and free conditions. Results confirmed what hypothesized: variability indexes (Standard deviation, Coefficient of variation and Poincaré plots) were significantly influenced by both environment and walking condition. Stability indexes (Harmonic ratio, Short term Lyapunov exponents, Recurrence quantification analysis and Sample entropy), on the contrary, did not highlight any change in the motor control.In conclusion, this study highlighted an influence of environment and testing condition on the assessment of specific characteristics of gait (i.e. variability and stability). In particular, for young healthy adults, both environment and testing condition affect gait variability indexes, whereas neither affect gait stability indexes.



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Biomechanics of the infant foot during the transition to independent walking: A narrative review

Publication date: January 2018
Source:Gait & Posture, Volume 59
Author(s): Carina Price, Stewart C. Morrison, Farina Hashmi, Jill Phethean, Christopher Nester
Recognising structural and functional development of the paediatric foot is fundamental to ensuring a strong theoretical framework for health professionals and scientists. The transition of an infant from sitting to walking takes approximately 9 months and is when the structures and function of the foot must respond to the challenges of bearing load; becoming increasingly more essential for locomotion. Literature pertaining to the phase of development was searched. A narrative approach synthesised the information from papers written in English, with non-symptomatic infant participants up to the development stage of independent walking or two years of age. A range of literature was identified documenting morphological, physiological, neuromuscular and biomechanical aspects of the infant within this phase of development. The progression of variable gait to a regular pattern is documented within a range of studies focusing on neuromuscular control and ambulation development. However, methodological approaches may have compromised the external validity of such data. Additionally, limited consideration for the specific function and development of the foot is evident, despite its role as the primary site of weight bearing and interface with the floor. A lack of consideration of infants prior to ambulation (i.e. before cruising or walking) is also apparent which prevents a reference baseline being used effectively. This review also identifies future research priorities such that a comprehensive understanding of foot development from a non-weight bearing to a weight bearing structure during locomotor advancement can be gained.



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Contents List

Publication date: October 2017
Source:Gait & Posture, Volume 58





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Real-time visual biofeedback during weight bearing improves therapy compliance in patients following lower extremity fractures

Publication date: Available online 20 October 2017
Source:Gait & Posture
Author(s): Marco Raaben, Herman R. Holtslag, Luke P.H. Leenen, Robin Augustine, Taco J. Blokhuis
BackgroundIndividuals with lower extremity fractures are often instructed on how much weight to bear on the affected extremity. Previous studies have shown limited therapy compliance in weight bearing during rehabilitation. In this study we investigated the effect of real-time visual biofeedback on weight bearing in individuals with lower extremity fractures in two conditions: full weight bearing and touch-down weight bearing.Methods11 participants with full weight bearing and 12 participants with touch-down weight bearing after lower extremity fractures have been measured with an ambulatory biofeedback system. The participants first walked 15meters and the biofeedback system was only used to register the weight bearing. The same protocol was then repeated with real-time visual feedback during weight bearing. The participants could thereby adapt their loading to the desired level and improve therapy compliance.ResultsIn participants with full weight bearing, real-time visual biofeedback resulted in a significant increase in loading from 50.9±7.51% bodyweight (BW) without feedback to 63.2±6.74%BW with feedback (P=0.0016). In participants with touch-down weight bearing, the exerted lower extremity load decreased from 16.7±9.77kg without feedback to 10.27±4.56kg with feedback (P=0.0718). More important, the variance between individual steps significantly decreased after feedback (P=0.018).ConclusionsAmbulatory monitoring weight bearing after lower extremity fractures showed that therapy compliance is low, both in full and touch-down weight bearing. Real-time visual biofeedback resulted in significantly higher peak loads in full weight bearing and increased accuracy of individual steps in touch-down weight bearing. Real-time visual biofeedback therefore results in improved therapy compliance after lower extremity fractures.



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Camera pose estimation to improve accuracy and reliability of joint angles assessed with attitude and heading reference systems

Publication date: January 2018
Source:Gait & Posture, Volume 59
Author(s): Karina Lebel, Mathieu Hamel, Christian Duval, Hung Nguyen, Patrick Boissy
Joint kinematics can be assessed using orientation estimates from Attitude and Heading Reference Systems (AHRS). However, magnetically-perturbed environments affect the accuracy of the estimated orientations. This study investigates, both in controlled and human mobility conditions, a trial calibration technic based on a 2D photograph with a pose estimation algorithm to correct initial difference in AHRS Inertial reference frames and improve joint angle accuracy. In controlled conditions, two AHRS were solidly affixed onto a wooden stick and a series of static and dynamic trials were performed in varying environments. Mean accuracy of relative orientation between the two AHRS was improved from 24.4° to 2.9° using the proposed correction method. In human conditions, AHRS were placed on the shank and the foot of a participant who performed repeated trials of straight walking and walking while turning, varying the level of magnetic perturbation in the starting environment and the walking speed. Mean joint orientation accuracy went from 6.7° to 2.8° using the correction algorithm. The impact of starting environment was also greatly reduced, up to a point where one could consider it as non-significant from a clinical point of view (maximum mean difference went from 8° to 0.6°). The results obtained demonstrate that the proposed method improves significantly the mean accuracy of AHRS joint orientation estimations in magnetically-perturbed environments and can be implemented in post processing of AHRS data collected during biomechanical evaluation of motion.



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Influence of outdoor running fatigue and medial tibial stress syndrome on accelerometer-based loading and stability

Publication date: Available online 23 October 2017
Source:Gait & Posture
Author(s): Kurt H. Schütte, Stefan Seerden, Rachel Venter, Benedicte Vanwanseele
Medial tibial stress syndrome (MTSS) is a common overuse running injury with pathomechanics likely to be exaggerated by fatigue. Wearable accelerometry provides a novel alternative to assess biomechanical parameters continuously while running in more ecologically valid settings. The purpose of this study was to determine the influence of outdoor running fatigue and MTSS on both dynamic loading and dynamic stability derived from trunk and tibial accelerometery. Runners with (n=14) and without (n=16) history of MTSS performed an outdoor fatigue run of 3200m. Accelerometer-based measures averaged per lap included dynamic loading of the trunk and tibia (i.e. axial peak positive acceleration, signal power magnitude, and shock attenuation) as well as dynamic trunk stability (i.e. tri-axial root mean square ratio, step and stride regularity, and sample entropy). Regression coefficients from generalised estimating equations were used to evaluate group by fatigue interactions. No evidence could be found for dynamic loading being higher with fatigue in runners with MTSS history (all measures p>0.05). One significant group by running fatigue interaction effect was detected for dynamic stability. Specifically, in MTSS only, decreases mediolateral sample entropy i.e. loss of complexity was associated with running fatigue (p<0.01). The current results indicate that entire acceleration waveform signals reflecting mediolateral trunk control is related to MTSS history, a compensation that went undetected in the non-fatigued running state. We suggest that a practical outdoor running fatigue protocol that concurrently captures trunk accelerometry-based movement complexity warrants further prospective investigation as an in-situ screening tool for MTSS individuals.



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Real-World Walking in Multiple Sclerosis: Separating Capacity from Behavior

Publication date: Available online 16 October 2017
Source:Gait & Posture
Author(s): Matthew M. Engelhard, Stephen D. Patek, John C. Lach, Myla D. Goldman
BackgroundHabitual physical activity (HPA) measurement addresses the impact of MS on real-world walking, yet its interpretation is confounded by the competing influences of MS-associated walking capacity and physical activity behaviors.ObjectiveTo develop specific measures of MS-associated walking capacity through statistically sophisticated HPA analysis, thereby more precisely defining the real-world impact of disease.MethodsEighty-eight MS and 38 control subjects completed timed walks and patient-reported outcomes in clinic, then wore an accelerometer for 7 days. HPA was analyzed with several new statistics, including the maximum step rate (MSR) and habitual walking step rate (HWSR), along with conventional methods, including average daily steps. HPA statistics were validated using clinical walking outcomes.ResultsThe six-minute walk (6MW) step rate correlated most strongly with MSR (r=0.863, p<10⁻²⁵) and HWSR (r=0.815, p<10⁻¹¹) rather than average daily steps (r=0.676, p<10⁻¹¹). The combination of MSR and HWSR correlated more strongly with the 6MW step rate than either measure alone (r=0.884, p<10⁻¹⁴). The MSR overestimated the 6MW step rate (μ=10.4, p<10⁻⁷), whereas the HWSR underestimated it (μ=−18.2, p<10⁻¹⁹).ConclusionsConventional HPA statistics are poor measures of capacity due to variability in activity behaviors. The MSR and HWSR are valid, specific measures of real-world capacity which capture subjects’ highest step rate and preferred step rate, respectively.



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Analysis of data collected from right and left limbs: Accounting for dependence and improving statistical efficiency in musculoskeletal research

Publication date: January 2018
Source:Gait & Posture, Volume 59
Author(s): Sarah Stewart, Janet Pearson, Keith Rome, Nicola Dalbeth, Alain C. Vandal
ObjectivesStatistical techniques currently used in musculoskeletal research often inefficiently account for paired-limb measurements or the relationship between measurements taken from multiple regions within limbs. This study compared three commonly used analysis methods with a mixed-models approach that appropriately accounted for the association between limbs, regions, and trials and that utilised all information available from repeated trials.MethodFour analysis were applied to an existing data set containing plantar pressure data, which was collected for seven masked regions on right and left feet, over three trials, across three participant groups. Methods 1–3 averaged data over trials and analysed right foot data (Method 1), data from a randomly selected foot (Method 2), and averaged right and left foot data (Method 3). Method 4 used all available data in a mixed-effects regression that accounted for repeated measures taken for each foot, foot region and trial. Confidence interval widths for the mean differences between groups for each foot region were used as a criterion for comparison of statistical efficiency.ResultsMean differences in pressure between groups were similar across methods for each foot region, while the confidence interval widths were consistently smaller for Method 4. Method 4 also revealed significant between-group differences that were not detected by Methods 1–3.ConclusionA mixed effects linear model approach generates improved efficiency and power by producing more precise estimates compared to alternative approaches that discard information in the process of accounting for paired-limb measurements. This approach is recommended in generating more clinically sound and statistically efficient research outputs.



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Executive functioning, concern about falling and quadriceps strength mediate the relationship between impaired gait adaptability and fall risk in older people

Publication date: January 2018
Source:Gait & Posture, Volume 59
Author(s): Maria Joana D. Caetano, Stephen R. Lord, Matthew A. Brodie, Daniel Schoene, Paulo H.S. Pelicioni, Daina L. Sturnieks, Jasmine C. Menant
BackgroundReduced ability to adapt gait, particularly under challenging conditions, may be an important reason why older adults have an increased risk of falling. This study aimed to identify cognitive, psychological and physical mediators of the relationship between impaired gait adaptability and fall risk in older adults.MethodsFifty healthy older adults (mean±SD: 74±7years) were categorised as high or low fall risk, based on past falls and their performance in the Physiological Profile Assessment. High and low-risk groups were then compared in the gait adaptability test, i.e. an assessment of the ability to adapt gait in response to obstacles and stepping targets under single and dual task conditions. Quadriceps strength, concern about falling and executive function were also measured.ResultsThe older adults who made errors on the gait adaptability test were 4.76 (95%CI=1.08–20.91) times more likely to be at high risk of falling. Furthermore, each standard deviation reduction in gait speed while approaching the targets/obstacle increased the odds of being at high risk of falling approximately three fold: single task − OR=3.10,95%CI=1.43–6.73; dual task − 3.42,95%CI=1.56–7.52. Executive functioning, concern about falling and quadriceps strength substantially mediated the relationship between the gait adaptability measures and fall risk status.ConclusionImpaired gait adaptability is associated with high risk of falls in older adults. Reduced executive function, increased concern about falling and weaker quadriceps strength contribute significantly to this relationship. Training gait adaptability directly, as well as addressing the above mediators through cognitive, behavioural and physical training may maximise fall prevention efficacy.



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Prefrontal cortex activation during a dual task in patients with stroke

Publication date: January 2018
Source:Gait & Posture, Volume 59
Author(s): Takayuki Mori, Naoyuki Takeuchi, Shin-Ichi Izumi
Dual tasks destabilize task performance as they involve competing demands for cognitive and physical resources. Several studies have reported that dual-task walking activates the prefrontal cortex (PFC), and recent studies have indicated a relationship between PFC and dual-task deterioration in healthy subjects. However, PFC activity during dual-task walking in stroke patients remains unclear. We investigated the association between PFC activity and dual-task interference on physical and cognitive performance in stroke patients. This study included 14 stroke patients and 14 healthy subjects who performed a calculation task while walking at a comfortable pace on the floor. PFC activity was assessed using wearable near-infrared spectroscopy. The calculation task and trunk linear accelerations were evaluated as measures of cognitive and physical performance. The dual-task deterioration on both physical and cognitive performance of stroke patients was significantly higher than in healthy subjects. PFC activation during dual-task walking was significantly lower in stroke patients. Although right PFC activation was negatively correlated with dual-task deterioration on physical performance in stroke patients, left PFC activation was negatively correlated with the dual-task cost on cognitive performance in healthy subjects. Thus, during dual-task walking, PFC activation might prioritize physical demands in stroke patients, but might prioritize cognitive demands in healthy subjects.



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Automated event detection algorithm for two squatting protocols

Publication date: Available online 26 October 2017
Source:Gait & Posture
Author(s): Wilshaw R. Stevens, Alicia Y. Kokoszka, Anthony M. Anderson, Kirsten Tulchin-Francis
IntroductionSquatting biomechanics assessed using motion analysis relies on the identification of specific events: start of descent, transition between descent/ascent and end of ascent. Automated identification reduces the time needed to process trials while allowing consistency across studies. The purpose of this study was to develop criteria for the identification of events and apply them to two squatting protocols in pathological patient and typically developing (TD) groups.MethodsThirty-four subjects with hip dysplasia and forty-one TD subjects were enrolled in this study. While instrumented with a full-body Plug-In-Gait marker set, participants performed two squatting protocols: hold squat, where subjects paused for a count of three at their lowest squat depth, and traditional squat, where the descent phase was immediately followed by the ascent phase. Reviewers analyzed the kinematic/kinetic waveforms of a subset of trials to develop criteria for events. Sagittal plane knee and vertical center of mass velocities were used to identify events and absolute vs. relative thresholds of the peak knee velocity were compared. These criteria were incorporated into an automatic event detection code.ResultsUsing a relative threshold algorithm, events were automatically identified in 244 of 259 total trials (94%). For the trials requiring manual placement of events (n=15 trials), there was perfect inter-rater reliability between research personnel.ConclusionsThe criteria developed for the automatic detection of squatting events was highly successful for both protocols in each participant group and was also highly reliable for research personnel to follow in the few instances where manual placement was necessary.



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Imbalance: objective measures versus subjective self-report in clinical practice

Publication date: Available online 23 October 2017
Source:Gait & Posture
Author(s): Elodie Chiarovano, Wei Wang, Pam Reynolds, Hamish G. MacDougall
BackgroundDizziness and imbalance are very common complaints in clinical practice. One of the challenges is to evaluate the ‘real’ risk of falls. Two tools are available: the patient’s self-report and the measure of the patient’s balance. We evaluated the relationship between these methods using the Dizziness Handicap Inventory (DHI) and measures of balance while visual inputs are perturbed with Virtual Reality (VR).Methods90 consecutive patients underwent the DHI questionnaire and the balance test. The DHI questionnaire was used to measure the subject’s perception of handicap associated with dizziness. The balance test measured the postural sway in several visual conditions: eyes open, eyes closed, and with an unpredictable visual perturbation using VR at several amplitudes of movement.ResultsNo correlation was found between the DHI score and the balance measurement. The visual perturbations allow us to characterize patients into three groups: one group with a high DHI score who did not fall on the balance test (5.5%), one group with a low DHI score who failed eyes closed on a compliant surface (9.0%), and one group of the remaining patients (85.5%). The correlation between the DHI score and the balance performance became significant on the remaining group of patients.ConclusionBoth subjective self-report and objective measure are important to characterize a patient. The use of VR visual perturbations allowed us to define three important groups of patients. VR visual perturbations provided additional information that helps explain the lack of correlation between DHI and objective test results.



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Recovery of balance function among individuals with total knee arthroplasty: Comparison of responsiveness among four balance tests

Publication date: Available online 16 October 2017
Source:Gait & Posture
Author(s): Andy C.M. Chan, Xi H. Ouyang, Deborah A.M. Jehu, Raymond C.K. Chung, Marco Y.C. Pang
Background and aimBalance deficits are common after total knee arthroplasty (TKA); however the responsiveness of commonly used balance measurement tools has not been well defined. The objective of this prospective study was to compare the internal and external responsiveness of four measurement tools in assessing recovery of balance function following TKA.MethodsA total of 134 individuals with TKA (95 women; age: 66.3±6.6years) completed the Balance Evaluation Systems Test (BESTest), Mini-BESTest, Brief-BESTest, and Berg Balance Scale (BBS) at 2, 4, 8, 12, and 24 weeks post-TKA. The Functional Gait Assessment (FGA) served as the anchor measure, and was also measured across these time points. Internal responsiveness was indicated by the standardized response mean (SRM), while external responsiveness was reflected by the degree of association of the changes of balance scores with those of FGA.ResultsThe SRM ranged from 0.60–1.14 for the BESTest, 0.40–0.94 for the Mini-BESTest, 0.27–0.91 for the Brief-BESTest, and 0.19–0.70 for the BBS, over time. The change in BESTest and Mini-BESTest scores predicted the change in the FGA scores across all time periods, except for the Mini-BESTest between weeks 12–24, accounting for 13–27%, and 12–24% of the variance, respectively. The Brief-BESTest scores only predicted FGA scores between the weeks 2-4 (R²=20%). The changes in BBS scores were not associated with the FGA.ConclusionThe BESTest was the most responsive in measuring recovery of balance among individuals with TKA. The Mini-BESTest is a reasonable option during time constraints.



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Editorial Board

Publication date: October 2017
Source:Gait & Posture, Volume 58





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Analysis of biases in dynamic margins of stability introduced by the use of simplified center of mass estimates during walking and turning

Publication date: January 2018
Source:Gait & Posture, Volume 59
Author(s): Kathryn L. Havens, Tatri Mukherjee, James M. Finley
The ability to control the body’s center of mass (CoM) is critical for preventing falls, which are a major health concern in aging populations. Control of the CoM has been assessed by characterizing dynamic margins of stability (MoS) which capture the dynamic relationship between the CoM and the base of support. Accurate estimation of CoM dynamics is best accomplished using a full-body marker set. However, a number of simplified estimates have been used throughout literature. Here, we determined the biases and sources of bias when computing MoS using four simplified CoM models, and we characterized how these biases varied in straight walking versus turning. CoM kinematics were characterized using a full-body marker set, the lower extremities and trunk, lower extremities only, an average of four pelvic markers, and one pelvic marker alone. Significant bias was demonstrated for most methods and was larger during turning tasks compared to straight walking. In the fore-aft direction, only overestimates in the MoS were observed, and these ranged from 15 to 110% larger than the true MoS value. In the mediolateral direction, both under- and over-estimates were observed and ranged from −175 to 225%. Across tasks, bias was smallest when using the lower extremity plus trunk (−23 to 62%) and pelvis average methods (−71 to 43%). Sources of bias were attributed to misestimates of CoM height, velocity, and position. Together, our findings suggest that the 1) lower extremity and trunk model and 2) pelvis average model should be considered in future studies to minimize bias when simplified models of CoM dynamics are desired.



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Moving from laboratory to real life conditions: Influence on the assessment of variability and stability of gait

Publication date: Available online 26 October 2017
Source:Gait & Posture
Author(s): Paola Tamburini, Fabio Storm, Chris Buckley, Maria Cristina Bisi, Rita Stagni, Claudia Mazzà
The availability of wearable sensors allows shifting gait analysis from the traditional laboratory settings, to daily life conditions. However, limited knowledge is available about whether alterations associated to different testing environment (e.g. indoor or outdoor) and walking protocols (e.g. free or controlled), result from actual differences in the motor behaviour of the tested subjects or from the sensitivity to these changes of the indexes adopted for the assessment. In this context, it was hypothesized that testing environment and walking protocols would not modify motor control stability in the gait of young healthy adults, who have a mature and structured gait pattern, but rather the variability of their motor pattern.To test this hypothesis, data from trunk and shank inertial sensors were collected from 19 young healthy participants during four walking tasks in different environments (indoor and outdoor) and in both controlled (i.e. following a predefined straight path) and free conditions. Results confirmed what hypothesized: variability indexes (Standard deviation, Coefficient of variation and Poincaré plots) were significantly influenced by both environment and walking condition. Stability indexes (Harmonic ratio, Short term Lyapunov exponents, Recurrence quantification analysis and Sample entropy), on the contrary, did not highlight any change in the motor control.In conclusion, this study highlighted an influence of environment and testing condition on the assessment of specific characteristics of gait (i.e. variability and stability). In particular, for young healthy adults, both environment and testing condition affect gait variability indexes, whereas neither affect gait stability indexes.



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Biomechanics of the infant foot during the transition to independent walking: A narrative review

Publication date: January 2018
Source:Gait & Posture, Volume 59
Author(s): Carina Price, Stewart C. Morrison, Farina Hashmi, Jill Phethean, Christopher Nester
Recognising structural and functional development of the paediatric foot is fundamental to ensuring a strong theoretical framework for health professionals and scientists. The transition of an infant from sitting to walking takes approximately 9 months and is when the structures and function of the foot must respond to the challenges of bearing load; becoming increasingly more essential for locomotion. Literature pertaining to the phase of development was searched. A narrative approach synthesised the information from papers written in English, with non-symptomatic infant participants up to the development stage of independent walking or two years of age. A range of literature was identified documenting morphological, physiological, neuromuscular and biomechanical aspects of the infant within this phase of development. The progression of variable gait to a regular pattern is documented within a range of studies focusing on neuromuscular control and ambulation development. However, methodological approaches may have compromised the external validity of such data. Additionally, limited consideration for the specific function and development of the foot is evident, despite its role as the primary site of weight bearing and interface with the floor. A lack of consideration of infants prior to ambulation (i.e. before cruising or walking) is also apparent which prevents a reference baseline being used effectively. This review also identifies future research priorities such that a comprehensive understanding of foot development from a non-weight bearing to a weight bearing structure during locomotor advancement can be gained.



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Contents List

Publication date: October 2017
Source:Gait & Posture, Volume 58





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Real-time visual biofeedback during weight bearing improves therapy compliance in patients following lower extremity fractures

Publication date: Available online 20 October 2017
Source:Gait & Posture
Author(s): Marco Raaben, Herman R. Holtslag, Luke P.H. Leenen, Robin Augustine, Taco J. Blokhuis
BackgroundIndividuals with lower extremity fractures are often instructed on how much weight to bear on the affected extremity. Previous studies have shown limited therapy compliance in weight bearing during rehabilitation. In this study we investigated the effect of real-time visual biofeedback on weight bearing in individuals with lower extremity fractures in two conditions: full weight bearing and touch-down weight bearing.Methods11 participants with full weight bearing and 12 participants with touch-down weight bearing after lower extremity fractures have been measured with an ambulatory biofeedback system. The participants first walked 15meters and the biofeedback system was only used to register the weight bearing. The same protocol was then repeated with real-time visual feedback during weight bearing. The participants could thereby adapt their loading to the desired level and improve therapy compliance.ResultsIn participants with full weight bearing, real-time visual biofeedback resulted in a significant increase in loading from 50.9±7.51% bodyweight (BW) without feedback to 63.2±6.74%BW with feedback (P=0.0016). In participants with touch-down weight bearing, the exerted lower extremity load decreased from 16.7±9.77kg without feedback to 10.27±4.56kg with feedback (P=0.0718). More important, the variance between individual steps significantly decreased after feedback (P=0.018).ConclusionsAmbulatory monitoring weight bearing after lower extremity fractures showed that therapy compliance is low, both in full and touch-down weight bearing. Real-time visual biofeedback resulted in significantly higher peak loads in full weight bearing and increased accuracy of individual steps in touch-down weight bearing. Real-time visual biofeedback therefore results in improved therapy compliance after lower extremity fractures.



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