Peripheral Nerve Electrophysiological Studies Of Post Stroke Shoulder Pain

Objective To analyze the electrophysiological features of peripheral nerve in upper extremity of post stroke shoulder pain.Method:Forty stroke patients were divided into shoulder-pain group(26patients) and without shoulder-pain group (14patients).Standard motor and sensory nerve conduction studies were performed with40stroke patients, including nerve conduction velocity and needle electromyography (EMG).Result The motor nerve conduction velocity in axillaris nerve, musculocutaneous nerve, medianus nerve of shoulder-pain group were evaluated, we found that the compound muscle action potential (CMAP) amplitudes were significantly decreased compared with the without shoulder-pain group(P=0.000,0.001,0.000). The CMAP amplitude of ulnaris nerve was significantly lower on the affected side than that on the unaffected side in without shoulder-pain group (p=0.000). The sensory nerve action potential (SNAP) amplitude of ulnaris nerve was significantly smaller on the hemiplegic side in shoulder-pain group than that in without shoulder-pain group (P=0.000).The incidence of spontaneous electrical potential of the deltoid and biceps in shoulder-pain group were significantly higher than those in without shoulder-pain group (P=0.044,0.044).Conclusion Peripheral nerve damage was found in post stroke shoulder pain, injury to motor neuro may be important for development of neuropathic pam.