Interference Screw Fixation Versus Pulvertaft Weave in a Simulated Early-Motion Suspensionplasty Protocol

PurposeTo compare interference screw fixation to Pulvertaft weave fixation in a cadaveric basal joint abductor pollicis longus (APL) suspensionplasty model with an early range of motion protocol. We asked whether the interference screw fixation would provide comparable initial stability while minimizing the dorsal incision and eliminating the prominent dorsal mass associated with the traditional Pulvertaft weave.MethodsSix matched cadaveric forearms underwent suspensionplasty with tendon fixation via an interference screw or a Pulvertaft weave. We then loaded the specimens to 10,000 cycles and used a modification of a previously validated cyclic pinch model. One third of the load required for maximal pinch strength was used. The APL was not loaded because we used the tendon for ligament reconstruction. We obtained measurements of residual trapezial space with feeler gauges after trapeziectomy, after suspensionplasty, and at 1,000-cycle intervals.ResultsSuspensionplasty with interference screw fixation maintained statistically significantly larger trapezial space heights compared with the Pulvertaft weave. Moreover, after the first 1,000 cycles, none of the specimens fixed with the interference screw lost further height up to the 10,000th cycle. All of the specimens fixed with the Pulvertaft weave continued to lose height with cycling, and 1 specimen showed contact of the first metacarpal with the scaphoid after only 1,000 cycles. With interference screw fixation, the height achieved initially and maintained through 10,000 cycles was an average of 5.5 mm. When the Pulvertaft weave was used, the height achieved was 3.0 mm initially, declining to 2.3 mm after 10,000 cycles. The polylactic acid interference screw was placed through a 5-mm dorsal stab incision and the extra tendon graft was cut flush as it exited the bone tunnel, eliminating the dorsal prominence associated with the Pulvertaft weave.ConclusionsAlthough traditional APL suspensionplasty with a Pulvertaft weave provides good initial stability, it requires a large dorsal incision and leaves a prominent dorsal mass that may be bothersome to some patients.Clinical relevanceFixation of the suspensionplasty with an interference screw appears to offer several advantages.