Open reduction and internal fixation of the proximal humerus with femoral head allograft augmentation “the French fry technique”

Abstract

Fractures of the proximal humerus account for 4%-8% of injuries to the appendicular skeleton. Most are stable, minimally displaced osteoporotic fractures in the elderly, and are the result of low-energy falls. A large majority of these patients regain adequate shoulder function without operative intervention. Surgery is considered in approximately 20% of patients because they require improved shoulder function for their activities of daily living or because of the significant deformity of their fracture and the need to restore functional alignment, length, and rotation in active, higher demand individuals. However, fixation of these fractures can pose a challenge due to poor bone quality and displacing forces of the rotator cuff. This is especially true in 3-part and 4-part fractures. These factors lead to the high failure rates seen with early attempts at osteosynthesis. In the last 2 decades, locking plate technology has been an innovation in treating these complex fractures. Despite the improvements in torsional strength and rigidity, outcome studies on locking plate technology demonstrate equivocal results with complication rates as high as 20%-30% and a revision rate of 10%. Specifically, these complications include avascular necrosis, varus collapse, intra-articular screw penetration, and postoperative stiffness. Varus collapse occurs when the weak osteoporotic bone fails around the implant. In turn, fibular strut endosteal augmentation was introduced to provide additional support and decrease implant failure rates in displaced fractures with varus coronal malalignment and significant metaphyseal bone loss. Although clinically successful and biomechanically superior to plate-only constructs, a few concerns remain. In turn, we introduce a novel technique of creating individual cancellous femoral head allograft struts or "French fries" that provides structural support for the humeral head but does not have the potential problems of a cortical fibular strut.