Partial Single Stage Exchange Arthroplasty With Retention of a Well Fixed Cemented Femoral Stem for the Treatment of Culture Negative Infection in a Bipolar Hemiarthroplasty: A Case Report

Abstract

Background: Prosthetic joint infection (PJI) is the second most common cause for revision following hip hemiarthroplasty (HHA) resulting in a mortality rate of 5.6%. The treatment of PJI is both challenging and controversial, without general consensus on best practice. In an attempt to avoid surgery, patients are commonly prescribed antibiotics, reducing the chance of detecting a microorganism, and culture negative infections are reported to occur in up to 21% of all PJI. Two stage revision is arguably the gold standard treatment but frequently these patients are too frail to undergo such extensive procedures. Some surgeons have attempted to avoid this by leaving well fixed implants undisturbed, effectively performing a partial single-stage revision.

Case presentation: A previously well 83 -year-old female patient presented with a gradual onset of increasing pain and difficulty walking. Just over 1 year prior to this presentation she fell at home and underwent an uncomplicated bipolar hemiarthroplasty. Clinical examination as well as serological and radiological investigations were suspicious for a periprosthetic infection. Her rapidly deteriorating clinical picture required prompt surgical intervention. In theater the patient underwent a single stage partial exchange arthroplasty leaving the well cemented femoral stem undisturbed. Although multiple samples were taken, no microorganism was identified. The patient has been followed up for 1 year and remains well, with no recurrence of infection. Her inflammatory markers have returned to normal and radiographs demonstrate no evidence of loosening of the total hip replacement.

Conclusion: The burden of infection following hip hemiarthroplasty is likely to parallel the predicted increase in hip fractures. The combination of physiologic frailty, osteoporosis and multiple medical comorbidities are pertinent factors for consideration in the development of a treatment strategy. A partial single stage revision THR performed by an experienced arthroplasty surgeon, along with expertly led antimicrobial therapy may be considered in carefully selected patients.

Keywords: culture negative; hip fracture; hip hemiarthroplasty; prosthetic joint infection; single stage revision.

Figure 1.

Initial post-operative AP radiograph demonstrating a satisfactory position of the bipolar hemiarthroplasty.

Figure 2.

A & B AP and lateral radiographs showing extensive acetabular chondrolysis, with lateral migration of the prosthesis and anterolateral acetabular bone erosion. Note: Outline of lytic area in the ilium indicative of an abscess cavity.

Figure 3.

Graph of CRP changes over time.

Figure 4.

Graph of ESR changes over time.

Figure 5.

A & B AP and lateral radiographs following partial revision total hip arthroplasty demonstrates incomplete filling of the acetabular abscess cavity with bone cement, and multiple screws stabilizing the acetabular shell.