Distance Weighted Matching in the Quantification of Excess Morbidity in External Hemipelvectomy and Hip...

External hemipelvectomy and hip disarticulation represent some of the most complex oncologic procedures; however, the actual excess morbidity compared to matched controls remains poorly quantified. We aimed to quantify the excess risk and resource utilization associated with major amputations using a distance-weighted methodology.

We conducted a retrospective cohort study using National Surgical Quality Improvement Program (NSQIP) data (2019-2023). Patients undergoing external hemipelvectomy or hip disarticulation (major amputation cohort) (n = 52) were compared to composite controls created from patients undergoing other pelvic oncologic procedures (n = 152). Composite controls were generated using distance-weighted matching based on 16 variables, including demographics, comorbidities, laboratory values, and procedural complexity. Primary outcomes included length of stay, uncomplicated outcome (defined as the absence of major complications, readmissions, reoperations, mortality, and length of stay ≤75th percentile), and massive transfusion.

The major amputation cohort demonstrated significant excess morbidity with 5.0 days longer length of stay (9.0 vs 4.0 days, p < 0.001), 40.3% lower uncomplicated outcome rate (34.6% vs 74.9%, p < 0.001), and a trend towards excess massive transfusion risk (5.8% vs 0.0%, p = 0.083).

Distance-weighted matching demonstrated that major amputations carry excess morbidity and resource utilization with prolonged hospitalization and reduced uncomplicated outcome probability.