Background There is increasing evidence for the use of intra-articular hyaluronic acid in the treatment of hip osteoarthritis (OA) using ultrasound-guided injections. More over, two-dimensional and more recently 3D ultrasonography is useful in detecting articular abnormalities in osteoarthritis.
Objectives Primary objective of our study was to assess the efficacy in pain relieving of ultrasound guided hip injections in patients with hip osteoarthritis. Secondary objective was to establish a correlation between a global score of structural damage based on 2D and 3D ultrasound images and response to treatment.
Methods patients with hip OA according to ACR criteria, grade 1 to 3 according to Kellgren and Lawrence were considerate eligible. Esaote Mylab 25 with 3D BL433 5-12 MHz probe was used. All subjects enrolled were treated with a course of three intra-articular jaluronic acid injections (800.000-1170000 dalton m.w.) 1 week apart and were followed every 3 months for a 6-months period after the last injection. The injections were performed under US guidance with an antero-superior approach according to the Magenta School’s method. Treatment efficacy was assessed through visual analogue scale (VAS) pain quantification (at baseline, at last injection and after 3 and 6 month). Additionally, 2D (longitudinal and transverse views) and 3D (longitudinal, transverse and coronal views) ultrasound images were collected and scored according to Qvistgaard method based on 4 items (osteophyte score 0-3, femoral head score 0-3, fluid score 0-2 and synovial profile score 0-2) and also through a global score derived from the sum of single item score.
Results Eleven patients (8 females and 3 males; age 47-83 years) were enrolled in this study. At 6 months after the injections course we observed a reduction in the pain VAS versus baseline mean values from 76.4 to 33.5 (p<0.05). Global Qvistgaard score was 4.2±0.8 and 5.1±0.2 (mean ± SD) using 2D and 3D views respectively. The VAS scores at baseline, 3 months and 6 months were significantly related to Qvistgaard scores (r =0.33 for 2D score and 0.64 for 3Dscore respectively, p<0.05). A linear regression model confirmed the role of radiological score as predictive of clinical response in terms of VAS
Conclusions our data confirm the efficacy of intra-articular medium m.w. hyaluronic acid in the treatment of hip OA, with a clinical improvement in pain for at least 6 months post injections course. Furthermore, our study suggests a correlation between echographic findings and clinical response, especially using 3D views.
Qvistgaard E et al.Intra-articular treatment of hip OA: a randomized trial of hyaluronic acid, corticosteroid, and isotonic saline. Osteoarthritis Cartilage 2006;14(2):163-70
Disclosure of Interest None Declared