Abstract
Carpal tunnel syndrome (CTS), an entrapment of the median nerve in the carpal tunnel, has been reported with increasing frequency in patients undergoing hemodialysis. During the last 8 months, 21 maintenance hemodialysis patients with CTS visited our hospital. These patients were 10 males and 11 females whose mean age was 56.8. The original disease in all of them was primary glomerulonephropathy. Ten of them had bilateral CTS; therefore 31 involved upper extremities are discussed here. The condition occurred most often in long-term hemodialysis patients. The mean duration of dialysis treatment was 107.2±34.1 months and only 3 out of the 21 patients were on dialysis less than 5 years. Diagnosis of CTS was based on the following symptoms and signs: hand pain, sleep paresthesia, numbness of the hand in a median distribution, positive Phalen test and wasting of the thenar eminence. Prolongation of distal motor latency was revealed in 25 out of 26 tested hands, it was absent in and the mean value in the other 20 was 7.81±3.05msec. 22 of 31 involved upper extremities had an active A-V fistula and 6 had previous surgery. Creation of an A-V fistula was statistically associated with development of CTS (P<0.002). However it seems likely that the increased incidence of CTS in bilateral hands and in long-term hemodialysis patients is due to other pathogenetic mechanisms rather than alteration in hemodynamics at the access site that increases venous pressure or the vascular “steal” phenomenon. Surgery for decompression of the median nerve at the wrist was performed on 18 hands of 16 patients. An S-shaped incision was made over the palm to the anterior aspect of the wrist with wide exposure of the flexor retinaculum. Visible thickening of the flexor retinaculum within the carpal tunnel was present in all 18 hands. They were cut by a sharp scalpel to release bundlelike constriction of the median nerve. In some instances there was venous engorgement within the neurilemmal sheath or serous exudation. After surgery, immediate relief of hand pain was felt in all patients. 6 to 8 weeks after surgery, the two-point discrimination test on the palm was improved, but numbness, wasting of the thenar eminence and prolongation of distal motor latency continued. It is important to make an early diagnosis of CTS and to perform early surgical decompression of the median nerve, because delay in treatment may cause irreversible damage to the entrapped median nerve.