Primary hip and knee replacement: "are we all operating on the same patients, even at the same institution?"

Survey studies have concluded that a lack of consensus exists between orthopaedic surgeons on indications for total hip and knee arthroplasty. Geographic variation in the rates of these operations has raised concerns that some surgeons inappropriately indicate healthier patients for surgery than others. The objective of this study was to compare primary hip and knee arthroplasty patients'pre-operative validated outcome scores between four orthopaedic surgeons operating at a single academic institution from 2003 to 2007.

A retrospective chart review was performed using CPT-4 codes to identify patients who underwent primary total hip or knee arthroplasty at our institution between June 2003 and June 2007. Pre-operative SF-36 and WOMAC scores were recorded for each patient Patient demographics including age, gender, body mass index (BMI), number of co-morbidities, life orientation score (a measure of patient optimism), smoking and alcohol use, education level, and occupation were also recorded. Statistical analysis using unbalanced analysis of variance (ANOVA) and Chi-Square test were used to compare data between the surgeons, with statistical significance set at P < 0.05.

There was no statistically significant difference in SF-36 or WOMAC stiffness and function scores between the surgeons. There was a small difference in WOMAC pain scores between the surgeons'total knee patients, but not total hip patients. The number of primary hip and total knee replacements performed by each surgeon ranged from 151 to 955, with a total of 1896 primary joint replacements by the four surgeons during the study period.

Patients undergoing primary total joint arthroplasty at our institution were equally disabled between four surgeons, despite the surgeons performing variable numbers of the procedures. Further comparative effectiveness research using validated outcome measures is warranted.