Tendon Repair With Intercalated Partial Extensor Carpi Radialis Longus Tendon Graft For Chronic Extensor Pollicis Longus Tendon Rupture

Background: The main treatment choices for chronic extensor pollicis longus (EPL) tendon rupture consists of tendon transfer and tendon repair with tendon graft. Tendon transfer with extensor indicis proprius (EIP) is currently considered the gold standard treatment which yields predictable and satisfactory results, but potentially compromises the strength of independent extension of the index finger. We propose our method of using a partial extensor carpi radialis longus (ECRL) tendon graft to repair chronic EPL tendon tears. Methods: The distal stump of the EPL was located through an incision at the basal joint level. The proximal stump was located through a curved incision at the dorsoradial wrist where the partial ECRL tendon graft was harvested. The tendon graft was subcutaneously transposed, sutured at both ends, and tensioned at full thumb extension with a neutral wrist position. Results: From March 2016 to June 2019, 23 patients (mean age: 59.7 years; mean follow-up: 29.6 months) were retrospectively reviewed. All the patients were followed for a minimum of 12 months. The final total active motion was 93.2% of the contralateral thumb. The mean Quick Disabilities of the Arm, Shoulder and Hand score was 6.0. There was one complication possibly due to poor EPL muscle quality, and the patient was subsequently treated with EIP tendon transfer. Conclusion: Our study showed that using a partial ECRL tendon graft to repair chronic EPL tendon rupture results in satisfactory functional outcomes. The advantages of this method include preservation of EIP function and using the same incision for graft harvesting and tendon repair. This method can be considered an alternative to EIP tendon transfer in patients with high demand for their index finger function.