Fixator-Assisted Nailing for Femur Neck Fracture Nonunion: A Case Series Study

Abstract

Background: Femoral neck fractures in young adults tend to be a result of high-energy trauma with a common pattern of Pauwels type III fracture, and they require timely and meticulous diagnosis and management. The objective of this study was to assess the clinical and radiological outcomes of the fixator-assisted nailing technique for managing femur neck fracture nonunion. Methods. This was a case series study of 16 patients with nonunion femoral neck fractures treated via a fixator-assisted nailing technique. Our inclusion criteria comprised the inclusion of any patient between the ages of 14 and 60 years old with a neglected neck of femur fracture or nonunion of the femur neck. In addition, we only included patients without further posttreatment trauma and without known metabolic diseases. The conditions that were excluded from this study included hip joints with preexisting osteoarthritis, radiographic evidence of avascular necrosis of the femoral head, and associated ipsilateral acetabulum fracture or fracture-dislocation. The fracture characteristics that were selected for the fixator-assisted nailing (FAN) technique were clear signs of pseudoarthrosis (such as sclerosis, clear fracture line defects, and failure of implants), in addition to evidence of varus malalignment. All fractures were Pauwels type III. Radiographs of the pelvis with both hips and a posteroanterior (PA) view of the injured hip were taken. Full weight bearing was allowed in all the patients from the first day postoperatively. Physical therapy was started for pain reduction modalities, stretching, and abductor strengthening.

Results: Union of the femur neck fracture and osteotomy site was achieved in all patients. An excellent functional status after four months of follow-up was found based on a modified Harris hip score questionnaire. At follow-up, no patient was suffering from pain or flexion contracture. Preoperative limb length discrepancy (LLD) (cm) was 1.8 ± 0.8 cm and postoperative was 0 ± 0.1 cm, p < 0.001. Preoperative neck-shaft angle (NSA) (o) was 85.6 ± 4.4 and postoperative was 126.9 ± 2.5, p < 0.001. Preoperative Pauwels angle (o) was an average of 50.4 ± 5.9 and postoperative was 31.3 ± 2.5, p < 0.001.

Conclusion: Our study indicates that FAN has a high success rate in young patients with nonunited femoral neck fractures.

Figure 1

An AP radiograph of the pelvis and right hip reveals a nonunion neck of femur fracture with varus deformity, assessed at 81 degrees Pauwels angle. Hardware that has been bent. (b) Intraoperative image shows pseudoarthrosis with lysis and scelorosis, as well as impending hardware failure. (c) Visualization of Pauwels' osteotomy execution during surgery. (d) The wedge bone was leveraged into the bone defect by 7 mm cannulated screws that were removed. (e)-(f) Radiographs depicting the postoperative outcome and a 12-month follow-up.

Figure 2

AP radiograph of the pelvis showing pseudoarthrosis of femur neck fracture with significant varus deformity: neck-shaft angle, 75 degree; Pauwels type 3, 63 degree.

Figure 3

(a) Postoperative radiograph sequence showing correction achieved and the position of implant within the femoral head and intramedullary canal. (b) 6 months postoperative follow-up showing 124 degree neck-shaft angle. (c) 4 months postoperative clinical photo showing the ability of the patient to squat. (d) External rotation (cross leg). (e) Internal rotation.

Figure 4

AP radiograph of left hip illustrating the preoperative and postoperative results.