Objectives To identify risk factors for progression of knee joint osteoarthrosis (OA).
Methods Prospective 5-year study included 110 female-patients with primary knee OA (ACR criteria), mean age – 59,11±8,95 y., average disease duration – 12,2±10,4 y. All relevant patients' data, including anthropometric parameters, case history, clinical examination findings, evaluation of pain intensity by VAS, knee joint status and therapeutic modalities used during the follow up period were recorded in individual patient's file. Instrumental diagnostic methods used in each patient included plain radiography of knee joints (gonarthrosis stage was classified by Kellgren J.- Lawrence J. scale), dual energy X-ray absorptiometry (DEXA) of lumbar spine, femoral neck and of subchondral bone of the hip and tibia, ultrasound (US) and MRI examination of knee joints.
Results After 5 year follow up radiographic progression was stated in 40 patients (Group 1), while in 70 patients Kellgren J.- Lawrence J. stage remained unchanged (Group 2). Patients from both groups were similar in terms of age and disease duration. Although, patients with OA progression had more intense knee pain when walking: 66,2±17,9 vs 55,1±18,24 (p=0,003) (mm); higher BMI: 33,2±6,05 vs 30,5±5,63 (p=0,021) (kg/m2); higher incidence of synovitis: 50,0% vs 18,6%, p=0,001, and bone marrow edema in medial tibia aspect: 72,5% vs 27,1%, p=0,001, higher rate of serious medial meniscus damage: 52,5% vs 24,3%, p=0,003 as compared to patients from Group 2 without OA progression. Patients' re-examination in 5 years revealed similar statistically significant difference between the groups in all evaluated parameters. Discriminate analysis identified the following major risk factors, responsible for gonarthrosis progression: obesity, synovitis and bone marrow edema. Based on identified factors and their coefficients a predictive model was suggested (with area under the curve – AUC- equal to 0,87), allowing to prognosticate the future course of the disease in a particular patient with high precision, i.e. 75% sensitivity and 78% specificity.
Conclusions Obesity, synovitis, bone marrow edema- are major risk factors responsible for progression of knee OA.
Disclosure of Interest None declared