Background and aim: Flexible flat foot is a common deformity in lower extremity, the foot arch collapses and the ground reaction forces does not apply properly to the foot. Backward walking is a common rehabilitive technique and is utilized to improve strength and balance. The purpose of this present study is to compare the salient points vertical ground reaction force measurements in flat foot patients while walking forward and backward with those of healthy subjects using a force plate system.
Materials and methods: 10 flexible falt foot female subjects  and 10 healthy female  subjects were  recruited to participate in this study. Each Subject walked 5 times forward and 5 times backward and the vertical ground reaction force was measured by a force platform.
Results: The results of this present study suggest a significant difference in kinetic pattern of forward walking compared to backward walking in both healthy and flexible flat foot participants. The force related to first peak of vertical ground reaction force was significantly less in forward walking compared to backward walking (p=0.000). Whereas the force related to trough and second peak of vertical ground reaction force were significantly high in forward walking compared to backward walking (p=0.000).
Conclusion: The results of this study show that backward walking changes the ground reaction force compared to forward walking and the main characteristic of this difference is due to decrease of forces applied to the heel of foot which may be important in flat foot patients.

Background and aim: Virtual Reality is a computer technology with virtual environment and objects, which people manipulate virtual environment through active participation. The aim of this study was to determine the effect of practice in virtual environment on upper limb function of children with spastic hemiparetic cerebral palsy.
Materials and Methods: In this single blinded, randomized, controlled trial, 16 children with hemiparetic cerebral palsy were evaluated in a simple random sampling of Ahvaz city in 2 groups (virtual reality and control). Treatment protocol consisted of one and half hours sessions of practice in virtual environment for 4-week, every other day. Measures were conducted pre, post and 3-month after the treatment period by Pediatrics Motor Activity Log and Bruininks-Oseretsky Test of Motor proficiency. Sample randomization and data analysis by analysis of variance with repeated measures were conducted by SPSS-16 software in alpha level set at 0.05.
Results: Subjects in virtual reality group showed significant improvement (p<0.01) in post-test measures (bruininks-oseretsky test of motor proficiency, speed and dexterity: mean change from 0.25±0.06 to 1.22±0.23). Results were retained for both groups in follow up session.
Conclusion: Virtual reality technology through intensive and repetitive practice in an interactive and motivational environment is a promising method to improve upper limb function of children with hemiparetic cerebral palsy.