ObjectiveTo explore effectiveness of musculoskeletal ultrasound combined with Wide-Awake technique in extensor indicis proprius tendon (EIP) transfer for repairing extensor pollicis longus tendon (EPL) rupture. Methods A clinical data of 20 patients with spontaneous EPL rupture, who were admitted between January 2019 to June 2024 and met the inclusion criteria, was retrospectively analyzed. During EIP transfer surgery, the musculoskeletal ultrasound-guided incision marking combined with Wide-Awake technique was used in combination group (n=10) and the tourniquet-assisted surgery under brachial plexus block anesthesia in the control group. There was no significant difference in the baseline data between groups (P>0.05), including gender, age, affected side, cause and location of rupture, and time from injury to hospitalization. The accuracy of preoperative musculoskeletal ultrasound in predicting the actual tendon rupture site was evaluated in the combination group. Operation time, intraoperative blood loss, visual analogue scale (VAS) pain scores during operation and at 6 hours after operation, total incision length, and postoperative complications were recorded. Surgical outcomes were assessed at 12 months after operation using the specific EIP-EPL evaluation method (SEEM), which included measurements of thumb elevation loss, thumb flexion loss, index finger dorsiflexion loss, and total score. ResultsIn the combination group, the incision position marked by preoperative musculoskeletal ultrasound positioning was consistent with the actual tendon rupture position. Compared with the control group, the operation time and total incision length in the combination group were significantly shorter and the VAS score at 6 hours after operation was significantly higher (P<0.05). There was no significant difference in intraoperative blood loss or intraoperative VAS score between groups (P>0.05). All incisions in both groups healed by first intention. Two patients in the control group developed swelling and blisters in the tourniquet area, which subsided spontaneously without special treatment. All patients were followed up 12-14 months, with an average of 12.5 months. The thumb dorsiflexion function of all patients recovered to varying degrees. At last follow-up, the thumb elevation loss in combination group was significantly lower than that in control group, and the total SEEM score was significantly higher (P<0.05); there was no significant difference in thumb flexion loss or index finger dorsiflexion loss between groups (P>0.05). ConclusionMusculoskeletal ultrasound can accurately locate the site of tendon rupture, assist the Wide-Awake technique in implementing precise anesthesia, and adjust tendon tension while reducing tissue trauma, with satisfactory effectiveness.