gms | German Medical Science

Objective: Cubital Tunnel Syndrome (CuTS) is a common nerve damage that leads to motor and sensory deficits in the hand. Many patients present with pronounced muscle atrophy and hand dysfunction as a sign of severe nerve impairment. This prospective study aims to clarify if those patients benefit from surgical treatment on a long-term basis.

Methods: Between January 2017 and December 2020 83 consecutive cases of CuTS were treated surgically in our department. Of these, we were able to prospectively enrol 33 with pronounced/marked symptomatology and advanced muscular atrophy into the study. Clinical data of the treatment course, DASH (Disabilities of Arm, Shoulder and Hand) score, high-resolution ultrasound examination, electrophysiological examination, hand strength measurement as well as video and photo documentation of motor function (finger cross test (FCT), Froment sign) were performed preoperatively and 6 and 12 months postoperatively.

Results: 16 (48.5%) patients were treated with endoscopic assisted in situ decompression, open decompression and transposition was performed in 17 cases (51.5 %). 35.7 % (46.4%) showed improvement of motor deficits 6 and 12 month after the operation. Muscular atrophy improved in 6 % after 6 and in 15% after 12 months. Motor function improved in the FCT in 13% after 6 month and in 43.5% after 12 month. Froment sign was preoperatively positive in 93.5%. After 6 month 31% showed a negative Froment sign and after 12 month 37.9%. An improvement in motor nerve conduction velocity of 75 % and sensory nerve conduction velocity of 54.5 % was detectable after 12 months. An improvement of the DASH score was achieved in 65.2% after 12 months. A significant improvement in nerve structure, pseudoneuroma and CSA was not observed in any of the cases, neither after 12 nor after 6 months. However, it was shown that pathological findings on ultrasound, in particular the presentation of pseudoneuroma or abolition of the fascicle structure, were closely associated with a poor result.

Conclusion: Even in severe cases of CuTS with clear muscular atrophy and dysfunction of the hand, surgical treatment can lead to an improvement in function and, in some cases, a reduction in atrophy. Cases with short symptom duration and without clear changes in the preoperative ultrasound have better conditions.