Treatment for Ulnar Neuropathy at the Elbow

Overview

The purpose of the study is to investigate utility and appropriateness of treatment interventions taking into account the presumed mechanisms of two main varieties of ulnar neuropathy at the elbow (UNE). The investigators hypothesize that in patients with UNE by entrapment in the cubital tunnel (CTE) surgical release (simple decompression) is superior to conservative treatment. By contrast, in patients with UNE in the retrocondylar groove (RCC) surgical humero-ulnar apponeurosis (HUA) release (simple decompression) should not be superior to conservative treatment.

Ulnar neuropathy at the elbow (UNE) is the second most common focal neuropathy with annual incidence rate of 21 per 100.000. Therefore, in Slovenia UNE each year affects approximately 420 and in Europe 156.000 patients. In previous publications evidence was presented that idiopathic UNE consists of two conditions occurring 2-5 cm apart. In the first condition, affecting about 15% of UNE patients, the ulnar nerve is entrapped 2-3 cm distal to the medial epicondyle (ME) in the cubital tunnel (CTE). In the second condition, affecting the majority (about 85%) of patients, the lesion is located at the ME or up to 4 cm proximally in the retrocondylar groove (RCC). As no anatomical structure constricting the ulnar nerve is usually found in that segment, the most probable cause of UNE at this location is extrinsic ulnar nerve compression against the underlying bone. The investigators believe that these two groups of UNE patients need different therapeutic approaches: (1) surgical release for ulnar nerve entrapment distal to ME and (2) conservative treatment for extrinsic nerve compression in the RCC. The efficiency of this therapeutic approach was already evaluated and significant clinical improvement was found in 80% of UNE patients. However, the design of that study did not enable to obtain an indisputable evidence that outcome was a result of treatment approach. It is still possible that improvement observed in patient population was a consequence of natural history rather than therapy. To resolve this problem a properly designed randomized control trial is needed. The investigators believe such trial would prevent numerous unnecessary and delayed operations in UNE patients.