Surgical fixation for pathological fracture of the proximal femur can relieve pain and re-establish patient mobility [1, 3]. Cephalomedullary nail fixation is an accepted method for pathological fracture of the proximal femur. The biomechanical advantage of intramedullary nail systems has been reported [6–8]. A recent study demonstrated that cephalomedullary nailing was biomechanically superior to either a locking-plate or a 95-degree blade-plate construct . However, techniques for nail insertion may cause problems, such as heterotopic ossification, superior gluteal nerve injury, hip abductor muscle weakness, and limping gait [15–17].
A serious complication of intramedullary nail fixation is fat or tumour embolism that is probably generated by increased pressure during reaming within the closed intramedullary canal. These emboli can travel along the blood stream to the lung parenchyma and cause devastating pulmonary complications, and this has also been reported in fixation with an unreamed intramedullary nail [9, 18]. Using transoesophageal echocardiography, Coles, et al. quantified the embolic load to the lungs created by reamed and unreamed femoral nailing, and they found that emboli were generated with both methods . Those authors concluded that unreamed nailing did not protect the patient from pulmonary embolization of marrow contents. Kerr, et al. reported cardiac arrest in six patients during intramedullary nailing procedures for femoral bone metastases . Three of the six patients in that study had simultaneous fixation of both femurs, and four of the six died from embolus. Similarly, in a report by Charnley, et al., one of 52 patients developed hypotension during insertion of the second femoral nail in a single-stage operation, and subsequently developed cardiac arrest and died in the recovery room. A postmortem study revealed massive pulmonary embolus. Those authors recommended that a second surgery be separated by a 2-week interval from the first surgery to avoid this complication .
Another option for management of a metastatic lesion in the proximal femur is wide resection of the tumour and endoprosthetic reconstruction. However, although this method has a low mechanical failure rate, the complication rate varies widely, and the cost is comparatively high. Wide excision of a metastatic lesion has been recommended in patients with isolated hypervascularized tumours, such as in thyroid or renal cell carcinoma. Many studies suggested wide excision and endoprosthetic reconstruction of a metastatic lesion of the proximal femur in patients who might survive for a longer time. They recommended this reconstruction because the endoprosthesis has a lower rate of mechanical failure and a higher rate of implant survival than intramedullary nails [5, 14]. Endoprosthetic reconstruction was reported to have the lowest rate of mechanical failure (less than 3.7%), with complication rates of 6–35% [14, 22]. However the cost of this reconstruction, which is higher than that of other devices, must be considered when treating patients in developing countries.
Reports on the use of the LCP® Proximal Femoral Plate (Synthes, Inc.) in musculoskeletal oncology reconstruction are limited [11–13, 23]. Virkus, et al. reported bone union in 23 of 25 pathological fractures, nonunions, or oncologic reconstructions, with the advantage of a lower rate of implant failure in locking plates at a mean follow-up of 18.2 months . In the present study, we demonstrated a locking-plate fixation technique for pathological fracture of the proximal femur that did not result in pulmonary embolism, and it yielded satisfactory outcomes. No oxygen desaturation, which would have indicated pulmonary embolism, occurred. There have been reports of LCP® Proximal Femoral Plate (Synthes, Inc.) implant failure [24, 25]. However, these failures occurred in patients with mechanical collapse due to varus deformity with inadequate posteromedial support of severely comminuted fractures. In the present study, all patients with metastatic lesions had cement-augmented implants, and bone defects in patients with benign bone tumours were packed with allograft bone chips. Secure fixation augmented with cement or bone grafting can, thus, lessen the chance of fixation failure, as our series suggests. Most of the patients in this study could ambulate independently with or without an assistive device postoperatively.
The limitations of our study were its retrospective nature and the small number of included patients. However, our results suggest that using LCP® Proximal Femoral Plate (Synthes, Inc.) fixation for pathological fracture may reduce the incidence of pulmonary embolism and promote pain-free postoperative ambulatory status in these patients. None of the patients in our study experienced hardware failure. Further studies, particularly with more patients and longer follow-up periods, are needed to confirm the benefits of this implant in the treatment of existing or impending pathological fracture of the proximal femur.