Non-union of Conservatively Managed Radial Neck Fractures in Adults: A Systematic Review

Non-union of radial neck fractures in adults is rare. This review aims to identify factors contributing to the non-union of undisplaced radial neck fractures and assess treatment options and outcomes. Systematic searches of English articles in PubMed, Embase, Ovid Medline, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews were undertaken in September 2021 according to the PRISMA guidelines. The search terms were (fracture) AND (radial neck) AND (non-union OR non-union). Eligible studies reported adults who experienced undisplaced radial neck fractures that went on to non-union without prior surgical intervention. Fifteen case reports/series were included involving 29 non-unions in 27 patients. The largest study included eight patients. There were 11 males (38%) and 18 females (62%). The average age at the time of the presentation was 55 (range: 29-73). In 13 cases, comorbidities were commented on, including association with smoking in 4 (30%), diabetes in 3 (23%), and excessive alcohol in 5 (38%). The average time from injury to a diagnosis of non-union was 6.7 (range: 2-24) months. The average time of follow-up was 28.6 (range:6-84) months. Eight minimally symptomatic or asymptomatic non-unions were managed conservatively without complication. Seventeen symptomatic non-unions were managed operatively. Treatments included open fixation (1), open fixation with bone grafting (1), bone grafting alone (2), arthroplasty (2), radial head resection (2), and unknown surgery (7). Patients managed operatively achieved full or near-full, asymptomatic range of motion at an average of 5.4 (3-12) months postoperatively. Non-union is a rare complication of an adult radial neck fracture, and risk factors may include female gender, smoking, diabetes, and chronic alcohol. Persistence with non-operative management is encouraged as it can resolve symptoms with or without a radiographic union. Operative options range from bone grafting +/- fixation to arthroplasty. On average, the time from injury to the decision made to operate is 6.5 (3-12) months. A comfortable, functional range of motion is possible with all treatment strategies.