Intramedullary nailing of proximal humeral fractures

Abstract

The treatment of proximal humerus fractures has undergone a large number of different concepts over the last years. Beside conservative measures, a variety of operative techniques have been proposed. Decision-making is based on the specific fracture pattern, the quality of bone and the individual patient parameters such as biological age and functional needs. Fractures with minimal or no displacement should usually be treated nonoperatively, as good functional outcome for this group of fractures has been reported [1]. Fortunately, 70-80% of all fractures of the humeral head can be treated conservatively, because they are not dislocated. On the other hand, there is consensus that in displaced and highly comminuted four-part fractures and head-splitting fractures in the elderly, a primary hemiarthroplasty is recommended [2]. The treatment of displaced three-part and even four-part fractures of the proximal humerus remains controversial. The reported techniques show a wide range of different recommendations, such as percutaneous procedures using wires, pins or screws [3, 4], to open procedures with plate fixation or even joint replacement. The plate fixation of proximal humeral fractures is due to the introduction of angular stable locking plates, and reports show a good outcome [5, 6]. Nevertheless, plate fixation often needs an extended exposure of the fracture elements and can increase the risk of osteonecrosis of the humeral head by disturbing the blood supply. Bulky extramedullar hardware can lead to mechanical complications, as subacromial impingement, and loosening of the plate and screws in poor bone stock have been reported. Therefore, minimally invasive techniques with closed and indirect reduction have been advocated to preserve the soft tissue envelope and the blood supply to the humeral head and fracture elements. Intramedullary nailing is a common and usual therapy in the treatment of humeral shaft fractures. In proximal fractures, using intramedullary implants is associated with problems of secure fixation and achieving a rotational stability of the humeral head and its fragments. Therefore, because of the success of angular stable locking plates, angular and sliding stable locking nails have been developed [7-9]. These nails should provide multiplanar locking modes for a rigid fracture fixation, achieving a rotator cuff stability to allow early mobilization without the risk of secondary loss of reduction. Cadaver analyses have shown that the highest bone strength can be found in medial and dorsal aspects of the humeral head and that it decreases from cranial to caudal [10]. Implants should therefore provide secure fixation in this area. © Springer Berlin Heidelberg 2006.