The effect of ankle and knee immobilization on postural control during standing

BackgroundThis study examined the effects of ankle and knee joint immobilization on postural control in healthy young adults while standing.MethodsThe 24 participants included in this study participated in postural standing tests under four different constraint conditions: free joints, ankle immobilization only, knee immobilization only, and ankle‐knee immobilization. Tests were performed using a commercial balancing equipment (BiodexTM, Inc., NY, USA) and software.ResultsThe overall limit-of-stability score and duration to completion of task were obtained at 75% limit‐of‐stability (moderate level of difficulty). The overall limit‐of‐stability score of free joints (34.5 ± 9.1) were significantly different with the ankle immobilization only (26.0 ± 11.6), and ankle-knee immobilization (26.4 ± 7.4) conditions. The test duration increased in the following order: free joints (57.8 ± 10.9), knee immobilization only (62.5 ± 14.0), ankle immobilization only (68.0 ± 14.9), and ankle-knee immobilization (69.4 ± 17.7). The duration of the free joint condition greatly decreased than ankle immobilization only and ankle-knee immobilization conditions.ConclusionsThe ankle and knee joints have sufficient range of motion to prevent falls related to decrease postural stability due to insufficient range of motion or to improve postural stability.