Carpal tunnel syndrome in patients on long-term haemodialysis.

The purpose of this study was to describe the pathophysiology of carpal tunnel syndrome (CTS) in patients on long-term haemodialysis. We examined 110 patients, who had been having haemodialysis for chronic renal failure and had CTS, to clarify the clinical features and electrophysiological changes in peripheral nerves. There was a significant correlation between the incidence of CTS and the duration of haemodialysis. Compared with idiopathic CTS, CTS caused by long-term haemodialysis had relatively limited postoperative improvement. Symptoms recurred postoperatively in 11 patients (19%) of those with CTS caused by long-term haemodialysis. Electrophysiological measurements of sensory nerve conduction velocity showed that it was slower in distal segments of the median nerve in patients on haemodialysis compared with normal volunteers. Nerve conduction velocity in the carpal tunnel was significantly delayed (p < 0.05) in the patients with CTS on long-term haemodialysis. N9-13 interpeak latencies were significantly longer (p < 0.05) in subjects who had had haemodialysis for at least 10 years. All the patients with advanced destructive spondyloarthropathy had longer N9-13 interpeak latency. These results suggest that CTS in patients on long-term haemodialysis has its basis in neuropathy. The clinical course of CTS in these patients is different from that of patients with idiopathic CTS, because the neuropathy involves not only the carpal tunnel region, but also the proximal part of the median nerve both diffusely and progressively.