[Application of selective nerve block maintaining active finger flexion and extension in the treatment of stenosing tenosynovitis of fingers].

Objective: To explore the efficacy of ultrasound-guided selective nerve block anesthesia in the distal third of the forearm while maintaining active flexion and extension during surgery for stenosing tenosynovitis.

Methods: A retrospective analysis was conducted on 61 patients including 15 males and 46 females with American Society of Anesthesiologists(ASA)gradesⅠorⅡ, who underwent surgery for stenosing tenosynovitis in our hospital between January 2017 and January 2022. These patients, aged from 16 to 72 years old (weighing 44 to 75 kg), underwent selective nerve blocks targeting the median and ulnar nerves at the middle and distal third of the forearm, and the superficial branch of radial nerve at the dorsal radial side of wrist joint, under ultrasound guidance. A 0.5% ropivacaine solution was used for each nerve block. The anesthetic dosage for each nerve was recorded, and the efficay of each nerve block was monitored by acupuncture every 30 seconds post-administration. The onset time and ability to perform active finger flexion and extension were recorded. Outpatient or telephone follow-up was performed 1, 3 and 6 months postoperatively to evaluate the efficacy of release.

Results: The efficacy of anesthesia block was excellent in 60 patients and good in 1 patient. One patient with simple stenosing tenosynovitis of the middle finger reported slight pain intraoperatively, which resolved with additional block of superficial branch of radial nerve of the wrist. Superficial branch of radial nerve was blocked in 20 patients, with a single dose of (1.7±0.3) ml and the onset time of (0.6±0.2) min. Median nerve was blocked in 45 patients, with a single dose of (4.1±1.0) ml and the onset time of (1.2±0.3) min;Ulnar nerve was blocked in 16 patients, with a single dose of (3.9±0.5) ml and the onset time of (1.7±0.3) min. All the patients retained active flexion and extension of the fingers. All 61 patients were followed up for 6 to 10 months with an average of (8.0±2.0) months, and no recurrence was observed.

Conclusion: Ultrasound-guided selective nerve block of distal third of the forearm can provide safe, rapid and good anesthesia for patients undergoing surgery for stenosing tenosynovitis of fingers, while maintaining the active finger movement. This technique facilitates intraoperative assessment of release and improves overall surgical outcomes.