Interosseous membrane anatomy and functional mechanics.

Longitudinal forearm stability is maintained through the interaction of several anatomic structures. One such structure, the interosseous membrane, is a fibrous tissue with an oblique orientation from the radius to the ulna. The membrane maintains the interosseous space between the radius and ulna through forearm rotation and actively transfers forces from the radius to the ulna. The interosseous membrane's unique functional capabilities result from its anatomic and histologic organization, which produces a stiff structure with elastic properties capable of maintaining large loads. The interosseous membrane's load transferring ability reduces the forces placed on the radiocapitellar articulation, thereby protecting this joint. However, large chronic loading results in attenuation of the membrane fibers, thereby reducing longitudinal stability. Large sustained loads occur after radial head resection with concurrent interosseous membrane tears, resulting in the proximal migration of the radius and disruption of the distal radioulnar joint. Ultimately, the treatment option for severe membrane disruption combined with proximal migration of the radius is the creation of a single bone forearm.