Restoration of longitudinal forearm stability using a suture button construct.

PURPOSE: This study proposed a method of restoring the longitudinal stability of the forearm provided by the central band of the interosseous membrane (IOM) by using a percutaneously placed suture button construct. We hypothesized that supporting the forearm IOM with a suture button construct would restore longitudinal stability in a cadaveric model of the Essex-Lopresti lesion.

METHODS

We assessed 7 adult cadaver upper extremities radiographically for evidence of previous elbow, forearm, or wrist fracture. Each limb was mounted onto a materials testing system with the elbow held at 90° and the forearm in neutral. The intact specimen was loaded cyclically at 134 N to determine the native mobility of the forearm segment. Each specimen was tested after each of the following steps: radial head removal, transection of the IOM, and suture button construct reconstruction of the IOM. After the final reconstruction, each specimen was examined for forearm range of motion and evidence of neurovascular injury.

RESULTS

Removal of the radial head and sectioning of the IOM sequentially increased average proximal migration of the radius by 3.6 and 7.1 mm, respectively. After reconstruction with the suture button construct, the IOM was restored to the intact state with only the radial head removed. Forearm rotation was not compromised by the reconstruction, and there was no evidence of neurovascular injury in any specimen.

CONCLUSIONS

A percutaneously placed suture button construct can restore the longitudinal stability provided by an IOM. The method described did not limit forearm rotation. We encountered no neurovascular injury in the specimens tested in this series. This construct may be an effective adjunct when combined with bony reconstruction to treat longitudinal forearm axis injuries.