Distal clavicle fractures have low rates of union when treated with conservative measures. Operative treatment is generally recommended for Neer type II and V. Multiple fixation methods exist with no clear gold standard. The goal of the current study is to assess the outcomes and complications of distal clavicle fractures treated with one of three fixation methods: standard clavicular plate, hook plate or suture fixation about the coracoid.

This is a retrospective cohort study of surgically-treated unstable Neer type II and V distal clavicle fractures in adults. These operations were performed by multiple surgeons within a single healthcare system between January 2010 and September 2012. Patients were divided into three cohorts: pre-contoured clavicular locking plates, hook plates, and suture-only fixation methods. Univariate and mulivariate modeling analyses were performed.

A total of 74 distal clavicle fractures comprised the final cohort. Fifty-eight (77%) of these fractures were Neer type II; the remaining 16 (21.6%) were Neer type V. Median follow-up time was 12 months (range 10–28). BMI, smoking status, diabetes, and ASA class were similar among all cohorts. Twenty-one patients were treated with suture fixation alone (28.3%), 37 with a contoured clavicular plate (50%) and 16 with hook plate fixation (21.6%). Twenty-one patients (28.4%) experienced complications, including two hardware failures requiring revision surgery. A total of 10/16 (62.5%) patients with hook plates required hardware removal for irritation, compared to 6/37 (16.2%) with a contoured clavicular plate (OR=8.61, p value=0.001), and none with sutures alone. A total of 3/21 patients (14.2%) treated with suture fixation methods were diagnosed with adhesive capsulitis post-operatively; no patients in the plate fixation groups received this diagnosis. The Neer V group had a higher proportion of any complications (37.5%) compared to Neer II (25.9%), and a higher rate of stiffness (12.5% v. 1.7% in Neer II).

This study compared the outcomes of three different fixation methods for unstable distal clavicle fractures. The overall union rate with any method of operative intervention was very high (98.6%), consistent with previous studies. Hook plates had a much higher re-operation rate, mostly owing to a higher incidence of hardware removal, an expected outcome owing to the prominence of these plates in the subacromial space. Contoured clavicular plates were associated with a lower incidence of irritation and hardware removal than hook plates, although one patient in this group experienced loss of fracture fixation and went on to asymptomatic radiographic non-union. Suture-only fixation methods had the lowest rate of re-operation, with only one of 21 procedures resulting in failure and requiring revision. However, there was a significantly higher rate of adhesive capsulitis in the suture fixation cohort, perhaps due to the tethering effect of the clavicle to the coracoid or violation of the rotator interval. While this study supports that most distal clavicle fracture fixation methods can achieve stable union, there is a highly variable complication profile associated with each fixation method. The routine use of hook plate fixation cannot be recommended.