Article

The Hawthorne effect, a subcategory of reactivity, causes human
behavior to change when under observation. Such an effect may apply to gait
variation of persons with prosthetics or orthotics devices. This study investigated whether the presence of observers directly affects the gait
pattern of users of lower limb prostheses. STUDY DESIGN: Within-subject
intervention study. METHODS: Primary outcome measures were gait parameters of
initial double support time and upper body lateral tilt angle, which were
collected with a mobile sensor attached to the subjects' back. To make subjects
feel unwatched, a certain amount of deception was necessary, and two different
conditions were created and statistically compared against each other: one in
which the subjects were initially unaware of the attention of observers and
another one in which the same subjects were aware of a group of observers.
RESULTS: Data from two subjects using trans-femoral prosthesis are reported.
Findings included a change in step initial double support percentage by up to
14.2% (p = 0.019). Considerable changes were also noted in secondary outcome
measures including speed, stride length, and stride symmetry. CONCLUSIONS: A
reactivity effect of observation exists in prosthetics gait analysis. More
comprehensive studies may be motivated by these preliminary findings. CLINICAL
RELEVANCE: Results of this study suggest that users of lower limb prostheses walk
differently when their gait is being assessed (e.g. in the prosthetist's office)
than in situations without observers. This may in part explain the clinical
experience that modifications of prosthetic fit or alignment provide only short-term betterment.
CI - (c) The International Society for Prosthetics and Orthotics 2015.

Langue : ANGLAIS