Factors predicting complication and reoperation rates following surgical fixation of proximal humeral fractures

Background: The purpose of this study was to report complication and reoperation rates following non-arthroplasty fixation of shoulder fractures determined on the basis of observational, population-based data from all inpatient admissions in California over an eleven-year period.

Methods: Records from all inpatient hospital discharges and subsequent readmissions related to operative non-arthroplasty treatment of proximal humeral fractures were obtained for patients in California from December 1994 through December 2005. These admissions were evaluated to identify patient and hospital characteristics associated with short and intermediate-term complications (within and after ninety days, respectively) as well as reoperation rates. Procedures performed included open reduction and internal fixation in 9254 patients, closed reduction and internal fixation in 1903 patients, and internal fixation without reduction in 302 patients.

Results: The short-term complications included mortality in 401 patients (3.5%), which was associated with a higher Charlson comorbidity index (odds ratio [OR] = 1.5, p < 0.001) and male sex (OR = 1.7, p < 0.001); and pulmonary embolism in sixty patients (0.5%), which was associated with male sex (OR = 2.2, p = 0.007) and patient age of seventy-five years or older (OR = 3.6, p = 0.001). Intermediate-term reoperations included conversion to hemiarthroplasty in 174 patients (1.5%); and conversion to total shoulder arthroplasty in eight patients (0.07%), which was associated with an age of fifty to sixty-four years (hazard ratio = 2.8, p = 0.007). Overall, an age of sixty-five years or older, male sex, residence in an area with an income in the lowest two quintiles, and the presence of preexisting comorbidities were associated with elevated risks of short-term complications but not of intermediate-term conversion to arthroplasty. The ninety-day revision rate was 5.3%.

Conclusions: Surgical fixation of proximal humeral fractures has a low complication and mortality profile. The data provided in this study can serve in counseling patients about risks associated with operative fixation of displaced proximal humeral fractures.