Objectives : To investigate the improvement rate of muscle weakness caused by lumbar disc herniation, 17 patients was treated with oriental medicine. Methods : To evaluate weakness of big toe extensor muscles caused by lumbar disc herniation, we measured the active range of motion(ROM) of big toe extension and muscle grading of big toe extensor muscles. We also measured numerical rating scale(NRS), oswestry disability index(ODI) and compared them with the active ROM of big toe extension. Results : 1. Progressive weakness of big toe extensor muscles was observed in 2 patients. Weakness of big toe extensor muscles were improved in 13 patients(76%). 2. Changes in manual muscle testing(MMT) scores corresponded with improvement rate of big toe extension. 3. Numerical rating scale(NRS) and oswestry disability index(ODI) improvement rate did not correspond with improvement rate of big toe extension. Conclusions : Muscle weakness caused by lumbar disc herniation can be treated with oriental medicine and progressive muscle weakness must be observed constantly.