Factors affecting radiographic progression of knee osteoarthritis.

Aim: To determine factors affecting radiographic progression of knee OA.

Methods: A cross sectional study comprise of patients with OA of knee joints. Kellgren and Lawrence (K-L) grading scale was used to evaluate the radiographic progression of knee OA. All of the patient were noted the demographic data including age, gender, duration of illness, body mass index and bone mass density. Lunar DEXA was used to measure total body-BMD (T-BMD), total bone mineral content (T-BMC) and legs-BMD (L-BMD).

Results: About 91 patients was enrolled in this study There were significant differences of body mass index (BMI) (p=0.01) between subgroup of knee OA grading. OR between grade 2 and grade 4 for BMI score highest tertile and BMI score lowest tertile were 5.26 (95% CI 0.59-47.20). There were no significant differences for age, sex, and duration of illness, T-BMD, L-BMD and T-BMC between subgroup of knee OA grading. There were a tendency of correlation on increased of age (OR 2.17, 95% CI 0.56-8.41), log-duration of illness, percentage of T-BMD (4% between grade 2 and 4) with increased of knee OA grading. There was a tendency decrease of percentage of L-BMD (of 7%) between grade 3 and 4.

Conclusion: In this cross sectional model, BMI was significantly associated with increased of knee OA grading or it could be said that BMI was risk factors for radiographic progression of OA. Subjects who already have knee OA and also have high BMI must be careful about the progression of their knee OA.