How Accurate and Effective Are Non-image-guided Thumb Basal Joint Injections When Performed by Experienced Fellowship-trained Hand Surgeons?

Abstract

Background: Corticosteroid injections are widely used for treating thumb carpometacarpal (CMC) arthritis, yet the accuracy of non-image-guided injections in expert hands is uncertain, with prior studies reporting intraarticular placement in about 60% of thumbs when performed by physicians with different levels of training. Despite their common use, there is a need to assess both the accuracy and the short-term clinical efficacy of these injections, particularly when performed without image guidance by fellowship-trained hand surgeons.

Questions/purposes: (1) What is the accuracy of thumb CMC injections performed without image guidance by fellowship-trained hand surgeons in an office setting? (2) What is the short-term efficacy of thumb CMC injections performed without image guidance?

Methods: We prospectively enrolled 33 patients with a mean ± SD age of 63 ± 12 years, 76% (25) of whom were female, with symptoms of basal joint arthritis that persisted despite conservative treatment, and we administered 1.5-mL corticosteroid injections without image guidance. We used descriptive statistics to analyze the outcomes, which included VAS, QuickDASH (Q-DASH), and Thumb Disability Examination (TDX) scores. Minimum clinically important differences (MCIDs) were defined as 0.9 points for the VAS, 18 points for Q-DASH, and 17 points for TDX.

Results: Of the 33 injections analyzed, 79% (26) were intraarticular. At 6 weeks, patients reported a mean improvement of 22 points in QuickDASH, 24 points in TDX, and 4 points in VAS scores. Importantly, 73% (24 of 33), 55% (18 of 33), and 82% (27 of 33) of the patients achieved the MCID in the patient-reported outcomes, respectively, suggesting that even without image guidance, corticosteroid injections can provide effective short-term relief for thumb CMC arthritis.

Conclusion: We found that about 79% of injections were placed intraarticularly, which was comparable with the findings of previous studies using image guidance, and provided meaningful improvements in pain and function for 6 weeks. These findings suggest that for experienced fellowship-trained hand surgeons, non-image-guided injections remain a viable option. Future studies should explore long-term outcomes and the potential role of adjunctive treatments such as antiinflammatory medications and splinting to enhance patient care.

Level of evidence: Level II, therapeutic study.