Proximal Ulna Osteotomy for Complex Fractures of the Distal Humerus: A 3-Dimensional Laser Analysis and Comparison With Olecranon Osteotomy

Biomechanics of plate fixation following traditional olecranon osteotomy versus novel proximal ulna osteotomy for visualizing a distal humerus injury

After a distal humeral injury, olecranon osteotomy (OO) is a traditional way to visualize the distal humerus for performing fracture fixation. In contrast, the current authors previously showed that novel proximal ulna osteotomy (PUO) allows better access to the distal humerus without ligamentous compromise. Therefore, this study biomechanically compared plating repair following OO versus PUO. The left or right ulna from eight matched pairs of human cadaveric elbows were randomly assigned to receive OO or PUO and repaired using pre-contoured titanium plates. Destructive and non-destructive mechanical tests were performed to assess stability. Mechanical tests on OO versus PUO groups yielded average results for ulna cantilever bending stiffness at a 90° elbow angle (29.6 vs 30.5 N/mm, p = 0.742), triceps tendon pull stiffness at a 90° elbow angle (28.2 vs 24.4 N/mm, p = 0.051), triceps tendon pull stiffness at a 110° elbow angle (61.9 vs 59.5 N/mm, p = 0.640), and triceps tendon pull failure load at a 110° elbow angle (1070.1 vs 1359.7 N, p = 0.078). OO and PUO elbows had similar failure mechanisms, namely, tendon tear or avulsion from the ulna with or without some fracture of the proximal bone fragment, or complete avulsion of the proximal bone fragment from the plate. The similar biomechanical stability (i.e., no statistical difference for 4 of 4 mechanical measurements) and failure mechanisms of OO and PUO plated elbows support the clinical use of PUO as a possible alternative to OO for visualizing the distal humerus.

Controversies in the Management of Bicolumnar Fractures of the Distal Humerus

Bicolumnar fractures of the distal humerus pose numerous treatment challenges for upper-extremity surgeons. Although open reduction and internal fixation demonstrates advantages compared with nonsurgical treatment, restoration of osseous anatomy can be difficult, particularly for comminuted, intra-articular fractures. Despite well-recognized complications, total elbow arthroplasty remains an option for elderly patients with fractures not amenable to fixation. Although indications remain controversial, distal humerus hemiarthroplasty has emerged as a potential alternative to total elbow arthroplasty in carefully selected patients with nonreconstructable fractures. Numerous controversies remain with respect to the management decisions for these complex injuries, including the optimal surgical approach, management of the ulnar nerve, and ideal fixation constructs for open reduction internal fixation. Our purpose is to review the management of bicolumnar distal humerus fractures in adult patients and discuss current controversies related to treatment.