Ultrasound-Guided Injection of a Corticosteroid and Hyaluronic Acid: A Potential New Approach to the Treatment of Trigger Finger

Background and Objectives: Stenosing tenosynovitis (trigger finger) is one of the most common causes of pain and disability in the hand, which may often require treatment with anti-inflammatory drugs, corticosteroid injection, or open surgery. However, there is still large room for improvement in the treatment of this condition by corticosteroid injection. The mechanical, viscoelastic, and antinociceptive properties of hyaluronic acid may potentially support the use of this molecule in association with corticosteroids for the treatment of trigger finger. This study examines the feasibility and safety of ultrasound-guided injection of a corticosteroid and hyaluronic acid compared, for the first time, with open surgery for the treatment of trigger finger. Methods: This was a monocentric, open-label, randomized study. Consecutive patients aged between 35 and 70 years with ultrasound-confirmed diagnosis of trigger finger were included. Patients were randomly assigned to either ultrasound-guided injection of methylprednisolone acetate 40 mg/mL with 0.8mL lidocaine into the flexor sheath plus injection of 1mL hyaluronic acid 0.8% 10 days later (n = 15; group A), or to open surgical release of the first annular pulley (n = 15; group B). Clinical assessment of the digital articular chain was conducted prior to treatment and after 6 weeks, and 3, 6, and 12 months. The duration of abstention from work and/or sports activity, and any treatment complications or additional treatment requirements (e.g. physiotherapy, compression, medication) were also recorded. Results: Fourteen patients (93.3%) in group A had complete symptom resolution at 6 months, which persisted for 12 months in 11 patients (73.3%), while three patients experienced recurrences and one experienced no symptom improvements. No patients in group A reported major or minor complications during or after corticosteroid injection, or required a compression bandage. All 15 patients in group B achieved complete resolution of articular impairment by 3 weeks after surgery, but ten patients were assigned to physiotherapy and local and/or oral analgesics for complete resolution of symptoms, which was approximately 30–40 days postsurgery. The mean duration of abstention from work and/or sport was 2–3 days in group A and 26 days in group B. Conclusions: Although the limited sample size did not allow any statistical comparison between treatment groups, and therefore all the findings should be regarded as preliminary, the results of this explorative study suggest that ultrasound-guided injection of a corticosteroid and hyaluronic acid could be a safe and feasible approach for the treatment of trigger finger. It is also associated with a shorter recovery time than open surgery, which leads to a reduced abstention from sports and, in particular, work activities, and therefore may have some pharmacoeconomic implications, which may be further explored. In light of the promising results obtained in this investigation, further studies comparing ultrasound-guided injection of corticosteroid plus hyaluronic acid with corticosteroid alone are recommended in order to clarify the actual benefits attributable to hyaluronic acid.