Ethnic and Gender Differences in the Functional Disparities after Primary Total Knee Arthroplasty

Background The benefits of TKA have been well documented. Whether these benefits apply equally across gender and ethnic groups is unclear. Given the underuse of TKA among certain demographic groups, it is important to understand whether gender or ethnicity influence pain and function after TKA.

Questions/purposes We determined (1) the influence of race, gender, and body mass index (BMI) on primary TKA functional scores and ROM before gender-specific implants; and (2) whether comorbidities influenced ROM and functional scores.

Patients and Methods We reviewed all 202 patients who underwent primary TKAs in 2004. We contacted 185 of the 202 patients, including 90 African-Americans, 87 Caucasians, four Asians, and four Hispanics (55 men, 130 women). Their average age was 66 years, and average BMI was 34.4 (range, 20-55). Knee Society scores (KSS) and ROM, patient demographics, and the Charlson Comorbidity Index (CCI) were recorded. Minimum followup was 24 months (average, 29.1 months; range, 24-60.3 months).

Results African-Americans had longer delays to presentation, higher BMI, and worse 2-year KSS. Women (all races) had higher BMI and worse preoperative flexion/arc ROM. African-American women had worse final ROM and had similar final gains in ROM (postoperative minus preoperative ROM) after controlling for confounders.

Conclusions Gender and race affected functional KSS and ROM variables. The worse results experienced by African-American women may be attributable to a longer delay to presentation. However, the scores and motion were high for all subgroups, and underuse of TKA in women and African-Americans cannot be justified based on a perception of lesser functional gains.

Level of Evidence Level III, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.