Are complication rates for elective primary total hip arthroplasty in Ontario related to surgeon and hospital volumes? A preliminary investigation

OBJECTIVE: To test the hypothesis that complication rates, for elective tot al hip replacement operations are related to surgeon and hospital volumes. DESIGN: Retrospective population cohort study. STUDY COHORT: Patients who had undergone elective total hip replacement in Ontario during 1992 as captured in the Canadian Institute for Health Inform ation database. MAIN OUTCOME MEASURES: In-hospital complications, 1- and 3-year revision ra tes, 1- and 3-year infection rates, length of hospital stay, and a-month an d 1-year death rates. RESULTS: Surgeons with patient volumes above the 80th percentile (more than 27 hip replacements annually) discharged patients approximately 2.4 days e arlier (p < 0.05) than surgeons with volumes below the 40th percentile (les s than 9 hip replacements annually) even after adjusting for discharge disp osition, hospital volume, patient age, sex, comorbidity and diagnosis. Comp lication rates requiring hospital readmission and death rates did not diffe r by surgeon or hospital volume (P > 0.05). CONCLUSIONS: There is no evidence to support regionalization of elective hi p replacement surgery in Ontario based on adverse clinical outcomes. Surgeo ns who perform a large number of total hip replacements are discharging pat ients earlier than less experienced surgeons, without any demonstrable incr ease in complications leading to hospital readmission. The explanation for this observation remains unknown and will require further study.