Radiographic Complications after Radial Head Replacement

Background Radial head arthroplasty (RHA) has become the preferred treatment for displaced radial head and neck fractures that cannot be fixed. While good short-term results are reported, mid- to long-term radiographic findings such as loosening, stress shielding, and radiocapitellar arthritis are not uncommon. The aim of this study was to analyze and quantify radiographic complications after primary RHA. We hypothesized high rates of radiographic complications could be appreciated at mid-term follow-up. Methods Adult patients who underwent RHA between 2006 and 2019 with at least six months of radiographic follow-up were included. Associated injuries, fracture pattern, implant design, radiolucency, stress shielding (SS), radiocapitellar arthritis, and heterotopic ossification (HO) were evaluated. Radiographic reviews were performed independently by two fellowship-trained orthopedic surgeons. Regression analysis was used to assess the relationship between demographics, clinical characteristics, and radiographic findings and reoperation. Results Sixty-three elbows amongst 62 patients with a mean age of 47 (range 15–83) met inclusion criteria, with an average follow-up of 748.8 days (range 230–4554 days). In regression analysis, implant type was not associated with an increased odds for radial head specific reoperation. Age, follow-up duration, fracture pattern, and associated ligamentous injuries were not associated with SS, arthritis, HO, or radiolucency. Male gender was associated with a lower degree of radiocapitellar arthritis (estimate − 0.40; 95% CI -0.72 - -0.08), as was the use of bipolar implants (estimate − 0.6; 95% CI -1.11 - -0.09). Conclusion 82.5% of patients following RHA had at least one radiographic complication at midterm follow up. Radiographic findings of SS (58.7%) and radiolucency (27.0%) are commonplace after RHA. Male gender and the use of bipolar implants may be protective against radiographic radiocapitellar arthritis. However, the clinical implications of these radiographic findings remain to be seen. Level of Evidence: III Type of Study: Prognostic