Comparative study on the effectiveness of corticosteroid injections between trigger fingers with and without proximal interphalangeal joint flexion contracture.

UNLABELLED: Trigger fingers with proximal interphalangeal joint flexion contracture are suggested to have a poorer response to corticosteroid injection than those without contracture, though this has not been proven scientifically. We compared the clinical response to corticosteroid injection between trigger fingers with and without proximal interphalangeal joint contracture, and investigated the influence of the injection on the A1 pulley and flexor digitorum tendons using ultrasonography. One month after injection, pain was significantly reduced in the no contracture group, and 56% of trigger fingers with proximal interphalangeal joint contracture resolved. Before injection, relative thickening of the A1 pulley and flexor digitorum tendons, and a partial hypoechoic lesion of the flexor digitorum superficialis tendon were observed in the contracture group. One month after injection, the thickening of the tendons and the A1 pulley was reduced, but the partial hypoechoic lesion was still observed in significant numbers. We have demonstrated that the presence of a proximal interphalangeal joint contracture was associated with a reduced clinical response to corticosteroid injection, and we suggest that the pathologic change in the flexor digitorum superficialis tendon, represented by the partial hypoechoic lesion, contributed to corticosteroid injection resistance. LEVEL OF EVIDENCE: IV.

Use of quantitative intra-operative electrodiagnosis during partial ulnar nerve transfer to restore elbow flexion: the treatment of eight patients following a brachial plexus injury.

The transfer of part of the ulnar nerve to the musculocutaneous nerve, first described by Oberlin, can restore flexion of the elbow following brachial plexus injury. In this study we evaluated the additional benefits and effectiveness of quantitative electrodiagnosis to select a donor fascicle. Eight patients who had undergone transfer of a simple fascicle of the ulnar nerve to the motor branch of the musculocutaneous nerve were evaluated. In two early patients electrodiagnosis had not been used. In the remaining six patients, however, all fascicles of the ulnar nerve were separated and electrodiagnosis was performed after stimulation with a commercially available electromyographic system. In these procedures, recording electrodes were placed in flexor carpi ulnaris and the first dorsal interosseous. A single fascicle in the flexor carpi ulnaris in which a high amplitude had been recorded was selected as a donor and transferred to the musculocutaneous nerve. In the two patients who had not undergone electrodiagnosis, the recovery of biceps proved insufficient for normal use. Conversely, in the six patients in whom quantitative electrodiagnosis was used, elbow flexion recovered to an M4 level. Quantitative intra-operative electrodiagnosis is an effective method of selecting a favourable donor fascicle during the Oberlin procedure. Moreover, fascicles showing a high-amplitude in reading flexor carpi ulnaris are donor nerves that can restore normal elbow flexion without intrinsic loss.