The Effect of Leg Length Discrepancy on the Strength of Ankle Muscle.

, Heo, Jai Kyun; , Park, Si Bog; , Lee, Sang Gun; , Lee, Kang Mok; , Kim, Ing Gon; , Kim, Dong Won

Original Article

Journal of the Korean Academy of Rehabilitation Medicine 1999;23(5):1035-1038.

Heo, Jai Kyun , Park, Si Bog , Lee, Sang Gun , Lee, Kang Mok , Kim, Ing Gon , Kim, Dong Won

¹Department of Rehabilitation Medicine, College of Medicine, Hanyang University, Seoul, Korea.
²Department of Plastic Surgery, College of Medicine, Hanyang University, Seoul, Korea.
³Department of Anesthesiology, College of Medicine, Hanyang University, Seoul, Korea.

하지장부동이 발목관절 근력에 미치는 영향

허재균, 박시복, 이상건, 이강목, 김잉곤¹, 김동원²

한양대학교 의과대학 재활의학교실, ¹성형외과학교실, ²마취과학교실

Abstract

Objective
This study was designed to evaluate the relation of leg length discrepancy on ankle muscle strength.

Method
Twenty four adult women were tested (12 leg length equality and 12 leg length discrepancy). Leg length was measured by tape ruler from anterior superior iliac spine to medial malleolus, three times by three different trained examiners. The muscle strength (bilateral ankle dorsiflexors and plantarflexors) was measured by using Cybex 340 dynamometer at 30 degree/sec and 120 degree/sec.

Results
The mean value of leg length discrepancy was 0.89⁑0.24 cm. In leg length discrepancy group, the peak torque of ankle plantarflexor were 44.50⁑20.94 Nm in long leg and 51.83⁑12.75 Nm in short leg at 30 degree/sec angular velocity (p＜0.05).

Conclusion
We concluded that there were significant increase in plantar flexor peak torques of short leg than those of long legs at 30 degree/sec (P＜0.05). Perhaps the difference of the muscle strength might be due to compensatory mechanism of short leg in propulsion during gait.

Key Words: Leg length discrepancy, Ankle plantarflexor muscle, Peak torque