Investigating a Potential Limit to Access to Care: Preoperative Cutoff Values for Body Mass Index for Shoulder Arthroplasty

Introduction: The primary purpose of this study was to determine the number of patients who would be denied a complication-free total shoulder arthroplasty (TSA) based on implementation of body mass index (BMI) eligibility cutoffs.

Methods: The National Surgical Quality Improvement Program database was queried to identify all patients who underwent primary TSA. Patient demographics and 30-day postoperative complications were compared according to BMI stratification using the Pearson chi-square test and binary logistic regression analysis adjusted for age and modified Charlson comorbidity index. A BMI eligibility criterion of ≥40 kg/m2 was used to calculate the positive predictive value (PPV) to assess the number of complication-free TSAs that would be denied to avoid a complication in a single patient.

Results: A total of 23,284 patients who underwent TSA met inclusion criteria. The overall complication rate was 7.2%. Using a BMI cutoff of ≥40 kg/m2 would yield a PPV of 7% for all Major Complications. This means that 14 complication-free procedures would be denied to avoid a Major Complication. In addition, BMI ≥40 kg/m2 served as an independent risk factor for acute renal failure, pulmonary embolism, ventilator use >48 hours, and readmission. The PPV for these clinically significant complications using BMI ≥40 kg/m2 as a cutoff was 4.9%. This translates into 20 patients being denied a complication-free procedure to avoid a single clinically significant medical complication. If this policy was enforced on the 2,426 patients who exceeded BMI ≥40 kg/m2 in this study, nearly 2,307 patients would be denied the potential benefit of surgery to prevent 119 complications.

Conclusion: The use of eligibility criteria for primary TSA or RSA based solely on BMI threshold values presents a potential limitation in access to care to these patients who otherwise would have a complication-free procedure.

Level of evidence: Level III, prognostic, retrospective cohort study.