A Novel Antibiotic Spacer for Significant Proximal Femoral Loss - Surgical Technique

Abstract

Background: Infections of proximal femora with prosthetic implants in situ have long been a major concern in orthopedic surgery. The gold standard in the management of infected proximal femurs in the presence of prosthetic implants has traditionally been a two-stage revision. However, this is challenging in the setting of extensive bone loss.

Methods: A 3 case series of such infections leading to extensive loss of the proximal femur is presented. We specifically describe our technique of debriding the infected segments as well as utilization of a trochanteric slide osteotomy to resect the femur.We also demonstrate preparation of the "pseudoacetabulum" and femoral component with an antibiotic spacer.

Conclusion: The high cost of such a procedure is offset by reduction in time spent in hospital. The spacer also helps to allow mobilization by partial weight bearing on a stable femoral component and provide pain control which improves quality of life as compared to prolonged intravenous antimicrobial therapy.

Keywords: Antibiotics; Bone loss; Femur; Hip; Infection; Revision.

Fig. (1)

Post resection of prosthesis and debris. Note reamed acetabulum on the left.

Fig. (2)

Creation of pseudoacetabulum by compressing a 56mm Austin-Moore into the cement.

Fig. (3)

Cement formed around the nail is inserted into the femur.

Fig. (4)

Pelvic x-ray showing the retained femoral stem prior to the second revision.

Fig. (5)

Postoperative X-rays showing the temporary antibiotic spacer construct. Note the antibiotic cement does not surround the nail within the bone, as opposed to a pre-constructed antibiotic nail.

Fig. (6)

CRP trend in the pre and post operative period.

Fig. (7)

Definitive reconstruction with proximal femoral replacement and cone pelvis reconstruction.

Fig. (8)

X-ray and MRI showing pathological fracture with involvement of proximal femoral diaphysis.

Fig. (9)

Proximal femoral replacement as management of the pathological fracture.

Fig. (10)

Postoperative x-ray following 1st stage revision.

Fig. (11)

X-ray 3 years following 2nd stage revision with no evidence of loosening and signs of bone integration onto the prosthesis.

Fig. (12)

Preoperative MRI and postoperative x-ray of the pleomorphic sarcoma reconstructed with a coned pelvis.

Fig. (13)

Post operative x-ray of femoral spacer. Note long segment of nail buried into void from previous femoral component stem and preservation of coned pelvis.