Evaluation of Ulnar neuropathy on hemodialysis patients.

Background: Ulnar nerve entrapment at the elbow is the second most common upper extremity nerve involvement after median nerve involvement at the wrist or carpal tunnel syndrome (CTS) considering the frequency of occurrence in the upper limb with variable causes. Hemodialysis, because of elbow positioning during dialysis, upper extremity vascular-access, and underlying disease is one cause of ulnar entrapment. This study considers evaluating the effect of elbow positioning on ulnar involvement prevalence during dialysis.

Materials And Methods: This cross-sectional study started in June 2011 and completed in December 2011. The patients receiving dialysis with at least one symptom or sign of ulnar nerve involvement underwent nerve conduction studies. Electromyography testing (EMG) performed to confirm the ulnar neuropathy. To review the ulnar nerve, patients must be in supine position with arm in 90° abduction and elbow in 135° flexion. We stimulated the ulnar nerve at three different points, including 6 cm above and 4 cm below the elbow and over the wrist. According to the electrophysiological data, the intensity of nerve entrapment and possibility of associated polyneuropathy determined.

Results: Clinically and electrodiagnostically, evidence confirmed that ulnar neuropathy was present in 11 (27.5%) of 40 hemodialysis patients and in 10 (25%) of 40 peritoneal patients (P value: 0.83). Also, the prevalence of median neuropathy in hemodialysis and peritoneal dialysis patients was 14 (35%) and 10 (25%), respectively (P value: 0.33).

Conclusion: The frequency of median and ulnar neuropathy in hemodialysis patients is more than peritoneal dialysis, but this different is not significant. In addition, comparing sitting position with prolonged elbow flexion and supine position with elbow extension during hemodialysis, recommended doing hemodialysis in later position with using an elbow pad.