Respective association of joint space narrowing and osteophyte formation with knee symptoms and function in China

Joint space narrowing (JSN) and osteophytes are rarely studied separately regarding their risk factors and impacts on knee symptoms and function, particularly in the Chinese population.

This study utilized data from the Shunyi Osteoarthritis Study. Residents over 50 years old were randomly selected and completed a home interview questionnaire. Clinical assessments included measurements of height, weight, range of motion (ROM), a chair stand test, and a 50-foot walk test. Radiographs of the tibiofemoral joints were taken in a semi-flexed, weight-bearing position, and medial JSN and osteophytes grades were recorded (grades 0 to 3). Univariate analyses were used to screen variables, and multivariate analyses were conducted to investigate the respective risk factors for JSN and osteophytes, as well as their impacts on knee symptoms and function.

A total of 1,184 patients (795 females and 389 males; mean age 61.1 ± 7.4 years) were enrolled in this study. Multiple regression analysis revealed that older females with history of knee injury were significantly more likely to exhibit JSN and osteophytes on radiographs. JSN was associated with slower gait speed and increased knee pain. Tibial osteophytes were linked to reduced performance in the chair stand test, while femoral osteophytes were correlated with gait speed and lower SF-12 physical component summary scores. All these factors contributed to reduced ROM.

This study found that JSN and osteophytes had different impacts on function and symptoms in KOA. However, no differences in risk factors were observed between JSN and osteophytes.