Relationship between knee osteoarthritis and the locomotive syndrome risk tests: A cross-sectional study

Abstract

Objective: To determine the relationship between locomotive syndrome (LS) risk tests and knee osteoarthritis (KOA).

Study design: Cross-sectional cohort study.

Methods: In 2015, 225 people (male 84, females 141, mean age 67.9, range 30-90) were examined using LS risk tests, including the stand-up test, the two-step test, and the 25-question risk assessment, in Katashina Village in Gunma prefecture. The Japanese orthopaedic association defined LS risk test stage 1, difficulty with standing from a 40-cm-high seat using one-leg in the stand-up test, two-step test <1.3, the 25-question risk assessment ≧7, and defined stage 2, difficulty with standing from a 20-cm-high seat using both legs in the stand-up test, two-step test <1.1, the 25-question risk assessment ≧16. Persons with two or more of the following on the ultrasound (US) assessment were defined as having KOA: peripheral joint space (PJS) < 5 mm during weight-bearing; medial radial displacement (MRD) > 5 mm during weight-bearing; and osteophytes > 2 mm. If the residents had KOA in either knee, they were defined as having KOA.

Results: 45 residents had KOA in either knee. Logistic regression analysis adjusted for age, height, weight, gender, and knee pain was performed with stage 0 as reference. On the stand-up test, the odds ratio was 5.484 (95% confidence interval (CI) 1.966-15.297) for stage 1 and 2.067 (95% CI 0.426-10.017) for stage 2. On the two-step test, the odds ratio was 1.497 (95% CI 0.557-4.021) for stage 1 and 0.71 (95% CI 0.210-2.395) for stage 2. On the 25-question risk assessment, the odds ratio was 1.73 (95% CI 0.646-4.631) for stage 1 and 1.5 (95% CI 0.508-4.433) for stage 2.

Conclusions: A stand-up test of stage 1 had a significant relationship with KOA. This might suggest that proper care of KOA is needed to prevent progressive disability.