Association between carpel tunnel syndrome and arteriovenous fistula in hemodialysis patients

Background: Carpal tunnel syndrome is more common in hemodialysis patients than in the general population. In addition to uremic neuropathy, arteriovenous fistula has been identified as one of the possible causes for the development of carpal tunnel syndrome. Methods: Wrists of 279 hemodialysis patients who had arteriovenous fistula for at least 6 months served as the case group and the other intact wrists of the same patients served as the control group. Carpal tunnel syndrome was diagnosed clinically; however, 116 random patients underwent electrodiagnostic studies the day after hemodialysis. Results: Clinically, carpal tunnel syndrome was diagnosed less frequently in the contralateral wrist than in the wrist with arteriovenous fistula (12.2 percent versus 30.5 percent, p < 0.0001). Meanwhile, the authors found a positive correlation between the duration of fistula and the development of carpal tunnel syndrome (p < 0.028). The site of fistula (snuffbox, radiocephalic) used, however, had no effect on the rate of development of carpal tunnel syndrome (p > 0.2). Contrary to the clinical assessment, electrodiagnostic studies did not indicate any significant association between the frequency of carpal tunnel syndrome and arteriovenous fistula or its duration. With the nerve conduction velocity abnormalities observed in patients with uremic polyneuropathy, the authors believe that clinical diagnosis of carpal tunnel syndrome is more indicative of the development of the condition than the electrodiagnostic results. Conclusions: The authors' clinical results have revealed that hemodialysis patients are at considerable risk of developing carpal tunnel syndrome in the wrist with an arteriovenous fistula. These patients should be under close observation and receive routine checkup.