Iatrogenic ulnar nerve palsy associated with supracondylar humeral fracture in children: A systemic review on its management

Background: Supracondylar humeral fractures (SCHFs) are among the most common pediatric fractures. Closed reduction and percutaneous pinning are considered the established gold standard. Biomechanically, cross-pinning is resilient for any axial rotation, but the medial pin increases the risk of iatrogenic injury to the ulnar nerve. Objective: A systematic review was conducted to provide an evidence-based analysis of the literature on the management of iatrogenic ulnar nerve injury caused by the medial pin during closed reduction and percutaneous fixation of displaced SCHF in children. Methods: MEDLINE, SCOPUS, and ScienceDirect databases were searched to identify all articles that reported ulnar nerve injury caused by the medial pin during closed reduction and percutaneous fixation of displaced SCHF in children and suggested the management. Reference lists from the articles retrieved were further scrutinized to identify any additional studies of interest. Results: One thousand six hundred and six articles on SCHF treated by closed reduction and cross-pinning were identified initially with 25 studies included in the analysis after screening. Four thousand six hundred and seventy-five children sustained SCHF with a median age of 7 years. Of 3036 children treated by closed reduction and cross pinning, 205 (6.75%) were diagnosed with iatrogenic ulnar nerve injury. The management involves observation only, removal of the medial pin, or exploration. The average recovery time in the group treated by removal of wire was statistically shorter than the other two groups. Conclusion: The evidence suggests surgical exploration of the ulnar nerve can be delayed for up to 7 months, with most studies favouring observation only. In selected cases, immediate removal of the medial pin should be considered.