[Compression neuropathy of the cubital nerve at the elbow]

Compression neuropathy of the ulnar nerve at the elbow has numerous known etiologies, and the anatomy of the ulnar nerve around the elbow leaves it vulnerable to compression at numerous sites. The compression may be extrinsic such as in occupational neuropathy or in cases of postanesthesia neuropathy. The so-called idiopathic compression may be favored by some anatomic variations. The cubital tunnel retinaculum may be loose, leading to ulnar nerve dislocation or subluxation or tight compression of the nerve during flexion of the elbow. Bulging of the synovium in the floor of the tunnel may be the cause of compression in rheumatoid arthritis, whereas osteophytes may be the cause in degenerative osteoarthritis. Cubitus valgus or instability due to a pseudarthrosis of the lateral epicondyle or to ligamentous injury may stretch the nerve. The choice of a surgical technique must be based on (i) the pathophysiology of chronic nerve compression at the elbow, (ii) an understanding of the etiology of the nerve compression in the particular patient's case, and (iii) the knowledge of the potential technical drawbacks of the various operative procedures. Simple decompression is the first choice in case of minimal compression without instability of the nerve. Decompression of the nerve with a medial epicondylectomy is indicated in case of instability of the nerve and is the first choice in case of pseudarthrosis or malunion of the medial epicondyle. Ulnar nerve transposition is technically the most demanding procedure. Inadequate surgical technique creates new sites of compression.(ABSTRACT TRUNCATED AT 250 WORDS)