Surgical Treatment of Undisplaced Femur Neck Fractures in Dementia Patients Using Proximal Femoral Nail Antirotation

Abstract

Purpose: People with dementia have poor mobility and discharge outcomes following hip fractures. The purpose of this study was to evaluate the clinical and radiological results of internal fixation of undisplaced femur neck fractures (Garden types 1 and 2) by proximal femoral nail antirotation (PFNA) in dementia patients.

Materials and methods: We studied retrospectively 19 patients with undisplaced femur neck fracture. All patients were over 70 years of age, walked independently with a cane or crutches and suffered moderate-to-severe dementia. Patients were treated with PFNA and followed-up for more than 2 years. Revision, loss of fixation, complications, and walking ability outcomes were measured.

Results: In walking-ability evaluation, patients showed an average decrease of just 0.2 points at the final follow-up. Walking ability was evaluated from before injury to 4 weeks after surgery and decreased by less than 0.5 points. Radiological bone union was achieved in 17 cases; the average time to bone union was 4.14 months (range, 2.5-7 months). Complications included non-union in two cases and femoral head avascular necrosis in one case of non-union.

Conclusion: We found that for patients with osteoporotic bone tissues in their femoral heads or patients (e.g., those suffering dementia) for whom cooperating with medical workers for postoperative walking control or rehabilitation exercises is difficult, implanting a mechanically stable spiral blade for fixation of femoral neck fractures could facilitate walking after surgery.

Keywords: Dementia; Proximal femoral nail antirotation; Undisplaced femoral neck fracture.

Fig. 1. (A) A guide wire was inserted into the center of the femoral head. (B) The aiming zig for antirotation wire. (C) The aiming zig for antirotation wire was attached to the buttress nut and 2 antirotation wires were inserted into the femoral head. (D) A helical blade was inserted into the femoral head. (E) The compression instrument for the proximal femoral nail antirotation blade. (F) The compression instrument was attached to the blade and intraoperative compression was obtained over the buttress nut and the protection sleeve. (G) After compression using the compression instrument.

Fig. 2. An 82-year-old male patient with a femoral neck fracture was treated with the proximal femoral nail antirotation. (A) Pre-operative radiograph showing an undisplaced femoral neck fracture. (B) Radiograph at the final follow-up (34 months after surgery) showing solid union without any evidence of mechanical failure. (C) Magnetic resonance image showing complete union at the fracture site and no evidence of avascular necrosis of the femoral head. (D) 99mTc-hydroxymethane diphosphonate bone single-photon-emission computed tomography showing radiotracer uptake in the femoral head suggestive of femoral head viability.

Fig. 3. A 75-year-old male patient with a femoral neck fracture was treated with the proximal femoral nail antirotation (PFNA). (A) Pre-operative radiograph showing an undisplaced femoral neck fracture. (B) PFNA fixation performed within 24 hours of injury, and a radiograph showing a sclerotic change at the fracture site 18 months after surgery. (C) Computed tomographic radiograph 18 months after surgery showing a sclerotic change at the fracture site and suggesting non-union. (D) Necrotic zone located in the superior aspect of the femoral head on a mid-coronal image. (E) 99mTc-hydroxymethane diphosphonate bone single-photon-emission computed tomography showing no radiotracer uptake, suggestive of avascular necrosis of the femoral head.