Predictors of response to intra-articular steroid injections in patients with osteoarthritis of the knee joint.

Abstract

This study aimed to determine the factors associated with response to intra-articular steroid injection (IASI) in patients with knee joint osteoarthritis. One hundred seventy-four female patients, age ranging from 30 to 80years, diagnosed to have osteoarthritis of the knee joint, were given IASI. Response to IASI was assessed by using WOMAC and VAS at 2weeks, 4weeks and 3months. At 3months, the subjects were categorized as responders, partial responders and non-responders to treatment by IASI. Various factors were narrowed down to see their effect on response, namely age, BMI, smoking habits, comorbidities, presence of clinical effusion, radiographic score, local knee tenderness, range of movement and socioeconomic status. One hundred twenty-four patients completed the study. 16.1% showed 50% or more improvement in WOMAC score at 3months post IASI therapy, whereas 38.7% of OA patients had more than 50% improvement in VAS score. Out of all factors, range of movement, local knee tenderness and radiographic score of the affected joint are the three parameters which can predict the improvement in WOMAC score after 3months of IASI therapy (P=0.013, P=0.045 and P=0.000, respectively). Age of the patient can predict improvement in VAS at 3months post IASI (P=0.027). We conclude that age, range of movement, local knee tenderness and radiographic score of the affected joint can predict response to IASI after 3months of IASI therapy.