Flexor Carpi Radialis or Abductor Pollicis Longus in Ligament Reconstruction and Tendon Interposition - A Randomized Controlled Trial

Trapeziometacarpal osteoarthritis (TMC OA) is a great societal burden. Its prevalence has been reported as high as 36% in select populations, and is directly responsible for reduced work productivity and absenteeism in many cases. In 1949 Gervis originally described simply removing the offending bone, the trapezium, and trapeziectomy has since shown favorable outcomes. Many others have subsequently published similar clinical results with the same technique. However, it has been noted that with trapeziectomy alone there is the risk of metacarpal subsidence into the trapezial fossa over time, which may have an impact on patient outcomes. This observation was the impetus for the development of several more complex surgical interventions for TMC OA.

A recent Cochrane review investigated the literature available comparing seven surgical interventions for TMC OA. There were very few significant differences discovered, and they ultimately did not identify a single procedure as superior. The included studies however were noted as being of low quality, and the authors called for more robust trials with standardized outcome measures.

One of the more popular techniques reviewed is the trapeziectomy with ligament reconstruction and tendon interposition (LRTI). First described by Eaton and Littler, it has been met with widespread adoption, and has shown good results. It theoretically reconstructs the ligament responsible for maintaining the metacarpal's position, and also places a tendon interposed between the two bones (scaphoid and base of the first metacarpal) thus limiting its collapse. The most commonly used tendon for reconstruction of the volar beak ligament is the flexor carpi radialis (FCR), but recent reports have also advocated for use of the abductor pollicis longus (APL). The APL tendon already inserts onto the base of the first metacarpal, obviating the need for creating a bone tunnel, which is required when using the FCR. It can also be harvested without the need for additional incisions. Only one study has directly compared the two procedures, and the results were similar for both.

Based on the available literature, trapeziectomy with LRTI may confer minor advantages to simple trapeziectomy. Currently, surgeons at our institution unanimously prefer the LRTI procedure, however there is discord on which tendon is best suited for the reconstruction. We hypothesize that complications will be similar between the two procedures, but DASH scores and operative time will be significantly decreased when using the APL tendon for reconstruction.