Ulnar neuritis after open elbow arthrolysis combined with ulnar nerve subcutaneous transposition for post-traumatic elbow stiffness: outcome and risk factors

BackgroundUlnar neuritis (UN) is a common complication of open elbow arthrolysis for elbow stiffness. The purpose of this study was to evaluate the outcome of subcutaneous anterior transposition of the ulnar nerve during open elbow arthrolysis and to describe the risk factors for UN.MethodsWe retrospectively studied 260 patients with post-traumatic elbow stiffness who underwent routine ulnar nerve transposition during open elbow arthrolysis. Patient demographics, clinical characteristics, and incidence and reoperation rate of UN were recorded. UN was defined as new-onset ulnar nerve symptoms and no relief or worsening of pre-existing ulnar nerve symptoms during the period of postoperative rehabilitation. Factors affecting the development of UN were analyzed by univariate and multivariate analyses.ResultsA total of 9.2% of the patients had UN, 25% of whom required reoperation for progressive neuropathy. The Dellon grade of patients associated with UN at last follow-up improved significantly compared with that preoperatively. The mean arc of motion in patients with UN decreased during follow-up in a time-dependent manner. Univariate analysis showed that male sex, limited preoperative flexion and arc of motion, preoperative heterotopic ossification (HO), and preoperative ulnar nerve symptoms were significantly associated with the development of UN. Multivariate regression analysis revealed that preoperative HO was the only independent risk factor for the development of UN.ConclusionsUN is still an important complication, although ulnar nerve subcutaneous transposition was performed during open arthrolysis for post-traumatic elbow stiffness. Identified risk factors for UN, especially preoperative HO, should be taken into consideration before surgery.