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Introduction: Balance impairment and related injuries are common in elderly and patients with neurologic disorders. Ankle foot orthosies can influence on balance via improvement of movement disorders. Therefore the aim of this study was to investigate the effects of modified ankle-foot orthosis on balance performance in healthy elderly.
 
Materials & Methods: The research was conducted on ten healthy elderly aged above 60. The conventional ankle-foot orthosis and modified ankle-foot orthosis were used in this study (the posterior part of the orthosis in the heel region was removed to provide free movements in the subtalar joint). Balance parameters were measured with a force plate during double limb standing in opened eyes and closed eyes under three different conditions: conventional ankle foot orthosies, modified ankle foot orthosies and barefoot. Also functional balance was assessed using Timed Up and Go test. Ethics code: IR.MUI.REC.1396.3.345.
 
Findings: The results of this study indicated that using modified ankle-foot orthosis did not significantly change standing balance parameters compared to barefoot condition (P>0.05). However, wearing conventional ankle-foot orthosis resulted in a significant reduction of the center of pressure excursion in the mediolateral direction (16%) compared to the barefoot condition (P=0.02).
 
Discussion & Conclusions: A simple modification in conventional ankle-foot orthosis did not impair standing balance performance of healthy elderly people. Additionally, the modified ankle-foot orthosis improved balance abilities compared to conventional ankle-foot orthosis. These observations could be attributed to the increased sensory feedback and using subtalar movements. It is recommended to study the effects of this modified orthosies on balance in the patients with neurological impairments who have foot and ankle movement disorders.