Background and aims: Balance for postural control which is a necessary ability to preserve daily functions has been evaluated widely for normal population and different groups. The aim of the present study was to compare the effect of manipulating visual, auditory and proprioceptive sensory information on the balance in healthy subjects and lower limb amputees.

Methods: In this quasi-empirical, 20 lower limb amputees and 20 healthy subjects participated and assigned into 2 groups. To assess postural control and balance, Computerized Dynamic Posturography was used. Using sensory organization test, balance was measured in 6 conditions (first: existence of sight, hearing and proprioception; second: Elimination of sight; third: Manipulation of vestibular system; fourth: Manipulation of proprioception; fifth: Elimination of sight and manipulation of proprioception and sixth: Manipulation of vestibular system and proprioception). Sensory organization test detected the balance score according to 2 variables of stability and displacement of the center of gravity.

Results: The findings showed that the stability score in healthy and amputees group in the first situation that there is each 3 senses: Visual, auditory and proprioceptive sensory is more than other situations. Stability score in the sixth situation of the 3 senses that are manipulated and removed was less than other situation. The average of stability score in healthy people was higher than low limb amputees group in the all 6 situations. Also, the average of displacement of the center of gravity in limb amputees subjects in the first condition that had 3 senses, visual, deep, and hearing was less than other situations. The average of displacement of the center of gravity in healthy subjects was higher group had a better balance in all the 6 conditions with lower limb amputees.

Conclusion: The results showed that healthy subjects group had a better balance in all the
6 conditions than amputees.