Background Osteoarthritis is a complex slowly progressive degenerative disease that affects joint components.Concomittant articular crystal deposits are able to stimulate an inflammatory response in OA through stimulation of the innate immune system.
Objectives Assess the contribution of sonographically detected crystal deposits to pain severity and functional disability in patients with knee OA (WOMAC score)
Methods Single-center cross sectional study. Adult patients diagnosed with knee OA diagnosed in accordance with ACR criteria from the Department of Rheumatology and Rehabilitation, Kasr Alainy School of Medicine, Cairo University were recruited. Clinical assessment of pain and functional status in patients with knee osteoarthritis was measured using: Western Ontario and McMaster Universities Arthritis Index score. The Logic p5 ultrasound machine (GE) with linear array probe (8–13 MHz). Examination of the articular and periarticular structures was performed by a trained rheumatologist according to the standard EULAR guidelines for exam of the knee. Serum uric acid was investigated. Plain radiography was done for comparison.
Results 53 patients (44 females 83% & 9 males 17%) were included, mean age 53.5 years ± 8.3 SD, disease duration 42.5 months ± 49.5 SD, body mass index mean 34.9±6.3 SD. Crystal deposits were sono-graphically diagnosed in 73 knees (68.9%), Monosodium urate deposits found in 33 knees (31.1%) and Calcium Pyrophosphate Dihydrate deposits were diagnosed in 67 knees (63.2%). Pain, stiffness and disability scores were significantly higher in OA knees with crystal deposition as compared to those without (p<0.05) that was in fact resistant to conventional analgesics, chondro-protectives and physiotherapy demanding the ongoing use of NSAIDs.
Conclusions Crystal deposition was associated with significantly increased pain intensity, knee joint stiffness and functional disability as measured by WOMAC in patients with knee OA.
Altman R, Asch E, Bloch D, Bole G, Borenstein D, Brandt K, et al., Development of criteria for the classification and reporting of osteoarthritis. Classification of osteoarthritis of the knee. Diagnostic and Therapeutic Criteria Committee of the American Rheumatism Association. Arthritis Rheum. 1986; 29(8):1039–49.
Naredo E, Cabero F, Palop MJ, Collado P, Cruz A, Crespo M. Ultrasonographic findings in knee osteoarthritis: A comparative study with clinical and radiographic assessment. Osteoarthr Cartil. 2005; 13(7):568–74.
Disclosure of Interest None declared