Proximal neuropathies in patients with poststroke shoulder pain

Abstract

BackgroundPoststroke shoulder pain (PSSP) could be due to proximal neuropathy or upper trunk brachial plexus lesion.AimThe aim was to detect any electrophysiological abnormality in the proximal nerves supplying shoulder structures that could contribute to PSSP.Settings and designCross-sectional study at institution: a university hospital, tertiary level of clinical care.Materials and methodsNerve conduction studies of the axillary, musculocutaneous, suprascapular, and lateral antebrachial nerves were done on both sides. In addition, electromyography of the deltoid, biceps brachii and infraspinatus on the hemiplegic side was performed on 30 stroke survivors with PSSP.Statistical analysis usedStatistical Package for the Social Sciences (SPSS ver.20). Description and analysis of the obtained data were done using appropriate tests.ResultsAxillary and musculocutaneous motor nerve latencies on the hemiplegic side were significantly prolonged compared with the normal side (P=0.012, 0.029, respectively). Moreover, axillary and suprascapular nerve amplitudes on the hemiplegic side were significantly lower than those on the normal side (P=0.008, 0.002, respectively). Twelve (40%) patients had electrophysiological abnormalities. Upper trunk brachial plexopathy was the most common abnormality which occurred in six (20%) patients. In addition, isolated axillary or suprascapular nerve lesion occurred at a similar frequency (10%).ConclusionProximal nerve lesions are not uncommon in PSSP patients.