Osteoconductive Agent (Norian) in Anterior Surgical Management
Osteoconductive Agent (Norian) in Anterior Surgical Management
Odontoid fractures can be successfully treated with anterior screw fixation. Odontoid fractures commonly occur in older patients who may have significant osteopenia. The authors examined the use of a bone substitute to overcome limitations encountered during a procedure in which anterior odontoid screw fixation is performed.
Two elderly patients with displaced, reducible acute odontoid fractures underwent anterior odontoid screw fixation. The intraoperative failure of the anterior vertebral cortex from osteopenic bone and failure to achieve complete contact between the dens and axis were encountered. The defects were supplemented by using the osteoconductive agent Norian. Outcome was evaluated to determine the utility of this method.
Occasional intraoperative failure of anterior odontoid screw fixation may be encountered. Supplementation of bone defects with this osteoconductive agent may facilitate successful bone union in selected patients.
Several accepted methods in the management of acute odontoid fractures have been described. Although external immobilization of nondisplaced or reducible fractures has often been used, certain fracture configurations, particularly found in older patients, may be associated with a higher rate of nonunion despite adequate external immobilization. The smaller surface area at the base of the dens in Type II odontoid fractures may contribute to this higher rate of nonunion. Surgical treatment has been recommended for management of fracture subtypes in which union is often not achieved after external immobilization. Although posterior atlantoaxial fusion, in which a modified Brooks' approach is performed with or without transarticular screw fixation, has been associated with a high fusion rate, this procedure eliminates axial rotation at the atlantoaxial joint. In contrast, odontoid screw placement via an anterior approach for acute odontoid fractures allows direct fixation across the fracture line without limiting axial rotation, and this procedure has also been shown to achieve high fusion rates.
Certain parameters have been associated with failure of the anterior odontoid screw technique, including inadequate reduction of the fracture, unfavorable fracture angulation, inability to achieve the appropriate trajectory secondary to chest wall limitations, and severe osteopenia. Although some of these factors can be identified preoperatively by using other methods, occasionally failure of the technique occurs intraoperatively. Anterior transarticular atlantoaxial screw fixation may be considered one surgical option, this technique will eliminate atlantoaxial rotation. We describe the technique and outcome obtained in two patients in whom anterior odontoid screw fixation was inadequate and whose fracture defects were treated with a calcium phosphate bone cement.
Odontoid fractures can be successfully treated with anterior screw fixation. Odontoid fractures commonly occur in older patients who may have significant osteopenia. The authors examined the use of a bone substitute to overcome limitations encountered during a procedure in which anterior odontoid screw fixation is performed.
Two elderly patients with displaced, reducible acute odontoid fractures underwent anterior odontoid screw fixation. The intraoperative failure of the anterior vertebral cortex from osteopenic bone and failure to achieve complete contact between the dens and axis were encountered. The defects were supplemented by using the osteoconductive agent Norian. Outcome was evaluated to determine the utility of this method.
Occasional intraoperative failure of anterior odontoid screw fixation may be encountered. Supplementation of bone defects with this osteoconductive agent may facilitate successful bone union in selected patients.
Several accepted methods in the management of acute odontoid fractures have been described. Although external immobilization of nondisplaced or reducible fractures has often been used, certain fracture configurations, particularly found in older patients, may be associated with a higher rate of nonunion despite adequate external immobilization. The smaller surface area at the base of the dens in Type II odontoid fractures may contribute to this higher rate of nonunion. Surgical treatment has been recommended for management of fracture subtypes in which union is often not achieved after external immobilization. Although posterior atlantoaxial fusion, in which a modified Brooks' approach is performed with or without transarticular screw fixation, has been associated with a high fusion rate, this procedure eliminates axial rotation at the atlantoaxial joint. In contrast, odontoid screw placement via an anterior approach for acute odontoid fractures allows direct fixation across the fracture line without limiting axial rotation, and this procedure has also been shown to achieve high fusion rates.
Certain parameters have been associated with failure of the anterior odontoid screw technique, including inadequate reduction of the fracture, unfavorable fracture angulation, inability to achieve the appropriate trajectory secondary to chest wall limitations, and severe osteopenia. Although some of these factors can be identified preoperatively by using other methods, occasionally failure of the technique occurs intraoperatively. Anterior transarticular atlantoaxial screw fixation may be considered one surgical option, this technique will eliminate atlantoaxial rotation. We describe the technique and outcome obtained in two patients in whom anterior odontoid screw fixation was inadequate and whose fracture defects were treated with a calcium phosphate bone cement.