Cement-a-TAN Temporary Proximal Femoral Replacement for Staged Joint Replacement - A Case Report

Abstract

Introduction: Infected non-unions of proximal femoral fractures are difficult to treat. If debridement and revision fixation is unsuccessful, staged revision arthroplasty may be required. Non-viable tissue must be resected; coupled with the introduction of an antibiotic-eluting temporary spacer before definitive reconstruction. Tissue microbiological diagnosis and targeted antibiotic therapy are required. In cases of significant proximal femoral bone loss, spacing options are limited.

Case report: We present a case of a bisphosphonate-induced subtrochanteric fracture that progressed to infected non-union. Despite multiple washouts and two revision fixations, the infection remained active with an unfavorable antibiogram. The patient required staged revision arthroplasty including a proximal femoral resection. To improve function through maintaining leg length and offset, the Cement-a-TAN was fabricated. It is a custom-made antibiotic-eluting articulating temporary spacer. Using a trochanteric entry cephalocondylar nail as a scaffold, bone cement was molded around the nail to fashion an anatomical and patient-specific proximal femoral spacer. Following resolution of the infection, the Cement-a-TAN was removed and a proximal femoral arthroplasty was successfully performed.

Conclusion: Cement-a-TAN is an excellent temporary spacing technique in staged proximal femoral replacement for infected non-union of the proximal femur where there has been significant bone loss. It preserves mobility and maintains leg length, offset, and periarticular soft-tissue tension, while offering good stability.

Keywords: Proximal femoral replacement; hip; infection; nail; spacer.

Figure 1

Coronal radiographs showing impending subtrochanteric fracture following a fall.

Figure 2

Coronal and oblique radiographs showing the original fracture fixation performed with dynamic condylar screw.

Figure 3

Intraoperative images showing initial revision to angled blade plate.

Figure 4

Coronal and oblique radiographs of the right proximal femur demonstrating a large soft-tissue collection.

Figure 5

Computed tomography images (coronal and sagittal) confirming non-union and gas within the soft tissues.

Figure 6

Intraoperative images showing resection of non-viable margins and revision fixation with angled blade plate.

Figure 7

Coronal and oblique radiographs showing persistent gas within the soft tissues and non-union.

Figure 8

Construction and implantation of the “Cement-a-TAN.”

Figure 9

Cement-a-TAN explanation.

Figure 10

Coronal, lateral, and oblique radiographs showing latest follow-up at 20 months postprocedure.