The Impact of Gunshot Injury on the Development of Heterotopic Ossification After Periarticular Elbow Trauma

To evaluate whether ballistic (gunshot) injuries increase the rate of severity of heterotopic ossification (HO) compared with blunt trauma in patients with periarticular elbow fractures.

Retrospective cohort.

Single Level 1 trauma center.

Study inclusion required patients of mature skeletal age diagnosed with a periarticular elbow fracture (OTA/AO 13A-C) with a minimum of 6 weeks radiographic follow-up between 2018 and 2024.

Data on demographics, injury characteristics, and surgical management were collected for the ballistic trauma cohort and blunt trauma cohort. HO was assessed using the Hastings/Brooker Classification. Secondary outcomes included postinjury stiffness defined as a flexion/extension arc of motion <100 degrees, revision surgery, and complications. Descriptive statistics were used to compare frequencies of categorical outcome variables between blunt and ballistic cohorts, and multivariable logistic regressions were used to identify risk factors for elbow HO occurrence and severity and all secondary outcomes.

A total of 171 patients met inclusion criteria including 65 Gunshot Wound (GSW)-related fractures (38%). Patients with GSW were younger [29.2 (range: 18-62) vs. 43.8 years (range: 18-93)] and more often male (84.6% vs. 51.9%). Overall HO occurrence was 61.4%. GSW was not significantly associated with HO (63.1% vs. 60.4%, P = 0.607). Distal humerus fractures were associated with increased HO risk [odds ratios (OR) 2.15] and severity (OR 2.63) compared with proximal radius/ulna injuries. Stiffness occurred in 73.7% of patients and was more common in distal humerus injuries than in proximal radius/ulna fractures (OR 2.50; P = 0.030). No significant differences were found in stiffness, revision surgery, or complication rates between GSW and non-GSW groups (OR 1.36; 95% CI: 0.537-3.455; P = 0.51).

Ballistic injury did not significantly increase HO risk or stiffness compared with blunt trauma in a civilian population. Consistent with the literature, fracture location, specifically distal humerus fractures compared with proximal radius/ulna injuries, seems to be an important driver for HO prevalence and severity. Identifying HO risk factors after periarticular elbow trauma can help clinicians stratify patient risk and guide preventive strategies for managing these complex injuries.

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.