Elbow incongruence with overload of the medial compartment has been implicated in the development of fragmented coronoid process (FCP). The objective of this study was to compare the distal ulnar ostectomy (DUO) with staged release of the interosseous ligament (DUO-L) and interosseous muscle (DUO-ML) to the proximal ulnar ostectomy (PUO) in ability to restore normal intra-articular elbow pressure and to unload the medial compartment. Intra-articular contact area (CA), mean contact pressure (mCP), and peak contact pressure (pCP) measurements were acquired for normal cadaveric elbows, after a radio-ulnar step was created, and after either a PUO or DUO with subsequent DUO-L and DUO-ML.
With a radioulnar incongruence, medial compartment CA decreased and mCP and pCP increased. After both the PUO and DUO-ML, the mCP and pCP returned to normal in the medial compartment. In comparison to baseline, neither treatment significantly unloaded the medial compartment.