Anatomic parameters for planning of interosseous ligament reconstruction using computer-assisted techniques

Purpose: Longitudinal radioulnar dissociation may result when both interosseous ligament (IOL) disruption and radial head fracture occur. Although radial head salvage or arthroplasty and temporary distal radioulnar joint pinning constitute the standard treatment for this injury, IOL reconstruction has been proposed to restore more normal forearm axis mechanics. To help provide an anatomic basis for IOL reconstruction, the purpose of this study was to characterize the geometry of the central band of the IOL and simulated IOL reconstructions. Methods: Twenty forearms free of pathology were dissected to bone-IOL-bone and computed tomography scans were taken. Computer models of radius-IOL-ulna were created from the computed tomography CT images, and computer-aided design software was used to measure key parameters for IOL reconstruction and simulate anatomic IOL reconstructions. Results: The insertion site locations of the IOL central band along the radius and ulna from the wrist were 57 ± 3% and 34 ± 4% of bone length, respectively. The angle at which the IOL central band inserts with the ulna was 24 ± 4 degrees, which agrees with previously reported values. We found that the minimum graft length needed to anatomically span both cortices through tunnels was 112 ± 14 mm. Conclusions: These data will help to provide a basis for planning and performing IOL reconstruction in cases of longitudinal radioulnar dissociation.