Cubital tunnel syndrome caused by amyloid elbow arthropathy in long-term hemodialysis patients: report of 4 cases.

Carpal tunnel syndrome occurs frequently in long-term hemodialysis patients. However, the literature contains few detailed reports of other nerve entrapment syndromes of the upper extremity in these patients. We encountered 4 cases in which cubital tunnel syndrome occurred in long-term hemodialysis patients. In all cases, a hypertrophic synovial mass projecting from the humeroulnar joint compressed the ulnar nerve, and Congo red staining revealed that the mass contained amyloid deposition. Synovial proliferation resulting from amyloid arthropathy of the elbow joint appears to be the primary cause of this disease.