Delayed-onset ulnar neuritis after release of elbow contracture: preventive strategies derived from a study of 563 cases.

PURPOSE: The purposes of this study were to determine whether delayed-onset ulnar neuritis (DOUN) after elbow contracture release can be prevented and to compare the efficacy of ulnar nerve decompression versus subcutaneous transposition.

METHODS

A retrospective study of 563 consecutive arthroscopic elbow contracture releases was conducted. The prophylactic efficacy of (1) subcutaneous transposition, (2) ulnar nerve decompression, (3) limited ulnar nerve decompression (7 to 8 cm), and (4) mini-decompression (4 to 6 cm) was assessed prospectively. The efficacy of prophylactic strategies (transposition, decompression, limited decompression, or mini-decompression) in preventing DOUN was compared by univariate survival analysis. Patients who underwent a subcutaneous transposition were matched with patients who underwent a standard open decompression or a limited decompression, according to gender, age (±10 years), diagnosis, and preoperative motion. This analysis was repeated after we excluded the patients who underwent associated open procedures (e.g., hardware removal).

RESULTS

DOUN occurred in 26 of 235 patients (11%) who did not undergo any prophylactic procedure versus 8 of 295 patients (3%) who underwent a prophylactic ulnar nerve decompression or transposition at the time of contracture release (P < .001). The neurologic impairment was significantly less severe after prophylactic decompression compared with patients without any prophylactic intervention (grade on Neuropathy Grading Scale, 2 vs. 4; P = .03). Ulnar nerve transposition and decompression were equally protective. The decompression length was the only factor significantly related to the failure of the prophylactic intervention (odds ratio, 0.19; P = .02). A mini-decompression was not as effective as a prophylactic procedure, whereas a limited decompression was equal to a standard decompression. The case-control analysis showed that the decompression and transposition had equal preventive effects but the transposition was associated with a higher rate of wound complications (19% vs. 4%, P = .03).

CONCLUSIONS

DOUN is a complication of arthroscopic elbow contracture release. Its incidence and severity can be reduced by limited open ulnar nerve decompression or transposition.

LEVEL OF EVIDENCE: Level II, prospective comparative study with retrospective analysis.