Isolated radial neck delayed union/nonunion after conservative treatment in adults: two case reports and a literature review

Background Treatment recommendations for isolated radial neck delayed union/nonunion are sparse, but include mainly conservative treatment, electro-stimulation, bone grafting, open reduction and internal fixation (ORIF) and radial head resection. The purpose of this study was to perform a literature review on isolated delayed union/nonunion of radial neck fractures and to evaluate the reported outcomes of proposed treatment strategies. Furthermore, we aimed to generate data-based recommendations for this rare pathology. In the second part of this paper, we report two clinical cases of delayed union of isolated radial neck fractures recently treated at the senior authors institution. Methods A literature search on PubMed was performed. We selected all papers with a documented delayed union, pseudarthrosis or nonunion of the radial neck. All papers were reviewed for patient demographics, patient occupation, treatment type and timing relative to the initial trauma, X-ray documentation and outcome. The two patients with delayed union after isolated radial neck fractures recently treated at our institution were evaluated for age, mechanism of injury, occupation, treatment and outcome. Clinical and radiological follow-up examinations were performed 6, 12 weeks, and 1 year after initial trauma. Final clinical evaluations included the Mayo Elbow Performance Score (MEPS) [1] and the Disabilities of the Arm, Shoulder and Hand (DASH) Score [2]. Results We found 17 cases reported in 11 articles matching our selection criteria of isolated radial neck delayed union or nonunion in adult patients. Average age was 55 years (range 29-73 years). The most frequent mechanism of injury was a fall on an outstretched arm from standing height. Initial treatment consisted of an arm sling for 1-4 weeks and physiotherapy. From the 17 included cases, six were operated on due to persistent pain. Three received bone grafts, one was supplemented with additional K-wire fixation, and three had radial head resections. Ten patients were treated conservatively: six were pain free and three were symptomatic at last follow-up; symptoms were not reported for one case. All surgically treated cases were pain free at the last follow-up, average 32 months (range 6-84). Of the conservatively treated group, eight of ten had documented nonunion. The two reported cases from our institution were initially treated conservatively for 4 and 6 months. Both had a radiologically documented delayed union. Both patients were operated on due to persistent pain precluding them from returning to work. At the last follow-up, MEPS and DASH scores were 100 points and 29 in one case and 100 points and 18 in the other, respectively. Conclusion Isolated delayed union or nonunion of the radial neck after conservative treatment in adult patients appears to be rare and often remains asymptomatic. Operative treatment is recommended for symptomatic delayed union/nonunion in patients with altered elbow function [3]. All surgically treated patients in our study with symptomatic delayed unions/nonunions had favorable clinical outcomes.