Complications and Outcomes After Surgical Intervention in Clavicular Nonunion

Background: Surgical repair of clavicle fractures is being employed more frequently, although most fractures are still treated conservatively. Both can result in nonunion. Current treatments for clavicle nonunion include open reduction with internal fixation (ORIF) plating without bone graft, ORIF plating with bone graft, and intramedullary pin fixation. Methods: We performed a systematic review and meta-analysis of studies reporting outcome, complication, and reoperation rates following surgical treatment for clavicle nonunion. Subgroup analysis was undertaken for outcome and complication rates between single plating and intramedullary pin fixation, bone graft use, and nonunion time length definition. Results: Fifty-three studies met inclusion criteria (1,258 clavicle nonunions). Mean clinical follow-up was 2.6 years. Seventy-two percent of nonunions were of the middle third, 1% were proximal third, 12% were distal third, and 15% were not reported. Forty-eight percent of nonunions were atrophic or oligotrophic and 17% were hypertrophic (35% not reported). Mean time to union was 13.6 weeks. Ninety-five percent of patients achieved union after the primary nonunion surgery. Overall complication rate was 17%. Single-plating fixation had significantly faster union time (15.2 vs. 19.8 weeks), lower reoperation rate (23% vs. 37%), and hardware removal rate (20% vs. 34%) than intramedullary pin fixation. Bone graft had significantly lower rates of delayed union (0.6% vs. 3.6%) but higher complication (15% vs. 8%) and reoperation rates (29% vs. 14%) than the other groups. Studies that defined nonunion after 3 months had significantly faster union times than the 6-month studies (13 vs. 16 weeks). The 3-month group had a significantly lower overall complication rate (12% vs. 25%) and hardware/fixation failure rate (3% vs. 5.5%) than the 6-month group. Conclusions: This systematic review is the largest report of complications, reoperations, and patient outcomes of clavicle nonunions after surgical intervention in the current literature. Plating showed faster time to union and lower reoperation rates than intramedullary pin fixation. Bone graft use showed lower rates of delayed union but substantially higher rates of complications and reoperations. Reports with a definition of nonunion at 3 months showed faster union times and lower complication rates compared to reports with a definition of nonunion that was 6 months or greater. Surgery could be considered at 3 months post-injury in cases of symptomatic non-united clavicle fracture, and plating results in reliable outcomes. Adjuvant bone grafting requires further study to determine its value and risk/benefit ratio. Level of Evidence: Level IV , Systematic Review. See Instructions for Authors for a complete description of levels of evidence.