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 v 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% v 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.