Comparison of muscle to other soft tissue in limiting elbow extension

Nine middle-aged women were examined to determine whether extension of the elbow in normal adults is limited primarily by muscle, or by ligaments and capsule. Terminal range of elbow extension was measured when the subject was normally relaxed and in the same subjects under conditions of paralysis induced by a myoneuro blocking agent. Relaxation of the unparalyzed subject was confirmed with a biofeedback machine. Paralysis resulted in increased elbow extension in all subjects. Since the myoneuro blocking agent affects only muscle and not the connective tissue, it is concluded that elbow extension in the normal adult woman is limited primarily by muscle.J Orthop Sports Phys Ther 1984;5(4):170-174.