Varus and valgus deformities in knee osteoarthritis among different ethnic groups (Indian, Portuguese and Canadians) within an urban Canadian rheumatology practice

ObjectiveTo prospectively evaluate consecutive patients with knee osteoarthritis who presented to a Canadian community rheumatology clinic and determine the prevalence of varus deformities of the knees and the incidence of forefoot overpronation in three ethnically different populations-a Canadian-born population, Indian-born population and Portuguese-born population. Use of different therapies for knee osteoarthritis in the clinic was also evaluated.MethodsData were collected on patient age, sex, body mass index (BMI), visual analog scale (VAS) pain, ethnic background, valgus/varus deformity at the knee and overpronation of the forefoot. Kellgren-Lawrence scores were assigned to plain radiographs. Charts were subsequently reviewed to evaluate rates of intra-articular steroid injection, hyaluronic injection, surgical referral and surgical referral in the first year after being seen in the clinic.ResultsEight patients who were Portuguese-born, 26 who were Indian-born and 33 who were Canadian-born were identified. Age was not significantly different. Women had more valgus changes than men (P = 0.04), and VAS pain was not significantly different between men and women. Significantly more varus deformity was noted in the Indian-born group than the Canadian-born group (P=0.002), and more valgus deformity was noted in the Portuguese-born than Canadian-born group (P = 0.009). There was a trend to lower BMI in the Punjabi-born group and lower VAS pain in the Canadian-born group. There was no significant correlation between BMI and VAS pain, nor age and VAS pain (r =−0.192 and −0.050 respectively). There was no significant association with either BMI or age and forefoot overpronation. No ethnicity differences in treatment such as use of intra-articular steroid/hyualuronic acid use, surgical referral or surgery were observed.ConclusionsPatient populations differed significantly in terms of varus and valgus deformities at the knee.