They assessed function at 6 weeks with a validated 70-point shoulder function assessment tool designed for patients with rheumatoid arthritis,8 which evaluates pain with motion, range of motion, and activities of daily living (higher scores indicate better shoulder function), and used a 100-point VAS to assess pain.3 Function scores showed greater improvement from baseline in the USG group than the PG group (15 vs 6 points; P=.012), as did pain scores (TABLE).
Ultrasound injections hurt less than palpation-guided injections
Three RCTs, all using triamcinolone, found that USG joint injections were less painful than PG joint injections (TABLE).4-6 Three of 4 studies found that USG injections also were associated with lower pain scores 2 weeks after injection, as measured with a standardized VAS.1,3-7 A common weakness of the 3 studies demonstrating a difference at 2 weeks was that they compared end scores rather than the magnitude of change from baseline between groups.
Two of 3 RCTs found that USG injections produced a greater reduction in the VAS pain score at 6 weeks, although the negative study was larger than the other 2 combined—184 patients, compared with a total of 285 patients for all 3 studies.1,3,7
Recommendations
The American College of Radiology’s practice guidelines for musculoskeletal ultrasound examination recommend using ultrasound to guide interventional procedures.9 However, no consensus statements comment on the use of ultrasound as opposed to palpation for guiding steroid joint injections.