Value of musculoskeletal ultrasound in assessment of rheumatoid hand function

Background Musculoskeletal ultrasound can be now considered a complement to physical examination in rheumatoid arthritis. This study evaluates the role of musculoskeletal ultrasound in assessment of rheumatoid hand function and underlying functional defects and disabilities in order to find out a possibly better tool for assessment. Results Hand grip weakness was significantly associated with metacarpophalangeal joints synovitis of ulnar 4 fingers ( p = 0.045), wrist joint synovitis ( p = 0.009), flexor tendons tenosynovitis of the ulnar 4 fingers ( p = 0.001), flexor pollicis longus tendon tenosynovitis ( p = 0.013). Hand function impairment by grip ability test was significantly associated with metacarpophalangeal joints synovitis of ulnar 4 fingers ( p = 0.009), wrist joint synovitis ( p = 0.004), and flexor tendons tenosynovitis of the ulnar 4 fingers ( p = 0.042). Multiple linear regression analysis showed that the most influencing factor affecting grip ability test and hand grip strength was ulnar 4 Flexor tendons tenosynovitis ( P = 0.023, P = 0.037) respectively. Conclusions Joint synovitis and tenosynovitis that are detected by musculoskeletal ultrasound can be used as an assessment tool for hand function in rheumatoid arthritis, since they are associated with reduced hand grip strength and impaired hand ability.