[Recurrences of carpal tunnel syndrome in long-term haemodialysis patients].

BACKGROUND: Multiple recurrences of carpal tunnel syndrome and increased malfunction of the hand caused by tendopathies and arthropathies occur in long-term (20 - 30 years) haemodialysis and are mainly influenced by beta2-microglobulin amyloidosis. METHOD AND CLINICAL MATERIAL: 18 patients undergoing haemodialysis for an average of 29 years had been operated on 96 times for bilateral CTS and recurrent CTS during a mean observation period of 12.6 years. In nine patients (12 hands), removal of the thickened flexor digitorum superficialis tendons III and IV had been performed. All but two patients suffered from amyloidosis, 17 of them suffered from additional tendo- and 13 from additional arthropathies. All procedures were performed under local anaesthesia, and in half of them a tourniquet was used. The outcome was evaluated both clinically and with nerve conduction studies.
RESULTS: 77 procedures for CTS-recurrences were performed. The first recurrence was observed after an average of 6.1 years (SD 2.8), the second after 4.6 (SD 3.1) and the third after 3.8 (SD 1.9) years. Whereas in case of a first (occasionally second or extremely seldom in a third) recurrence, another re-opening of the carpal tunnel with or without synovectomy, was sufficient to improve symptoms in the majority of patients, this was occasionally the case with a second but rarely with the third recurrence. In these latter patients, only resection of thickened superficial flexor tendon bundles, showing marked amyloid-deposits histologically, resulted in improvement of pain, as well as finger mobility in one third of the patients. The distal motor latency of the median nerve recovered after the primary operation in 86 %, and after the second (first recurrence) only in 53 %. After the third operation (second recurrence), the results after tendon removal were better than in cases after synovectomy alone.
CONCLUSION: In long-term (more than 20 - 30 years) haemodialysis patients suffering from arthropathies, tendopathies and recurrent carpal tunnel syndrome, removal of the flexor digitorum superficial tendons should be considered for the second recurrence to improve pain and finger mobility.