RESUMEN
The effect of different methods of exercise therapy in the treatment of patients suffering from lumbar segmental instability can be challenged in different following treatment periods. Compare of two different methods of exercise therapy in treatment of patients with lumbar segmental instability after three month. In this clinical trial study twenty-four patients' ranging 18-45 years old with signs of lumbar segmental instability were randomly divided into two groups. The first group did only the routine exercise and the second group did the routine exercise plus stabilizing exercises for eight weeks and continued it until three months after treatment. Studied variables included flexor and extensor trunk muscle endurance, pain intensity, functional disability, flexion and extension lumbar range of motion, right and left trunk muscle side were evaluated before, eight weeks and three months after treatment. Data was analyzed using k-s and repeated measurement tests. The findings showed that flexion lumbar range of motion, right and left trunk muscle side increased and pain, functional disability decreased in stabilizing exercise group. There is statically significant difference in the mean of this mentioned variables between two groups after 8 weeks [P=0.001]. The process of pain intensity and functional disability reduction and muscle endurance time increase was more in stabilizing exercise than routine exercise group, following three months exercise. Regarding the prolonged positive effects of stabilizing exercise in reduction of pain intensity and increase of functional ability and muscle endurance until three months after treatment, it is recommended to use this method along with routine exercises