gms | German Medical Science

Objectives/Interrogation: The stability of the thumb is necessary for hand function. The ulnar collateral ligament (UCL) of the metacarpophalangeal joint is the major stabilizer for grip and pinch activities. The prevalence of this injury is approximately 50 in 100000 per year, with 86% of complete rupture. The most common mechanism of injury is forceful abduction during sports.

Its not uncommon for the injury to be overlooked in the first visit to the ER, due to the lack of suspicion and incorrect physical examination and also because it doesn't appear on plain x-rays. In addition, the injury often does not heal by itself due to the frequently interposition of the adductor aponeuroses.

Sometimes the patients just seek for medical assistance with a very chronic injury (over 6 months) without arthrosis, which is challenging to decide the treatment. The decision depends on the degree of ligamentous injury and physical demands.

Many types of reconstruction using tendons grafts are described for the treatment, but there is always the damage in the donor's site. The use of suture tape as an internal brace is well established for other ligaments reconstructions. Shin et al recently published a biomechanical study comparing the strength of repair alone and repair augmented with tape in thumb UCL lesion in cadaveric specimens, demonstrating the superiority of the last procedure.

The goal of this study is to present the use of UCL augmentation in very chronic injury without arthrosis with a new technique.

Methods: The UCL and UCL accessory were identified during surgery and they were not trustable for repair. Krackow's style suture were made with a 2-0 fiber wire. The fiber wire and a 2-0 fiber tape were fixed distally with a 3X8mm bio-tenodesis screw (Arthrex, Naples, FL). The tension was adjusted with the MCP joint in 30° flexion to avoid restricted flexion in the joint, and the proximal side of the fiber tape were fixed with an equal screw. The patient wore a cast for 1 week and then a splint for 3 weeks when rehabilitation started.

Results and Conclusions: The immediate strength and stability of the repair were excellent, the passive range of motion was complete.

Three months after surgery the grip and the pinch were stronger than contralateral thumb. There was full range of motion.

This method looks promising for the treatment of this difficult chronic UCL injury without arthritis.