Comparison of patients treated with or without a spacer in two stage revision hip arthroplasty for periprosthetic joint infection

Functional Outcome after Reimplantation in Patients Treated with and without an Antibiotic-Loaded Cement Spacers for Hip Prosthetic Joint Infections

Purpose

A staged revision with placement of a temporary antibiotic-loaded cement spacer after removal of the implant is the "gold standard" for treatment of chronic prosthetic joint infection (PJI). It enables local delivery of antibiotics, maintenance of limb-length and mobility, easier reimplantation. However, bacterial colonization of spacers and mechanical complications can also occur. The aim of this study is to evaluate functional results and infection control in two-stage treatment of total hip arthroplasty (THA) PJI with and without a spacer.

Materials and Methods

A retrospective review of 64 consecutive patients was conducted: 34 underwent two-stage revision using a cement spacer (group A), 30 underwent two-stage revision without a spacer (group B). At the final follow-up, functional evaluation of patients with a THA in site, without PJI recurrence, was performed using the Harris hip score (HHS). Measurement of limb-length and off-set discrepancies was performed using anteroposterior pelvic X-rays.

Results

Most patients in group B were older with more comorbidities preoperatively. Thirty-three patients (97.1%) in group A underwent THA reimplantation versus 22 patients (73.3%) in group B (P<0.001). No significant differences in limb-length and off-set were observed. The results of functional evaluation performed during the final follow-up (mean, 41 months) showed better function in patients in group A (mean HHS, 76.3 vs. 55.9; P<0.001).

Conclusion

The use of antibiotic-loaded cement spacer seems superior in terms of functional outcomes and reimplantation rate. Resection arthroplasty might be reserved as a first-stage procedure in patients who are unfit, who might benefit from a definitive procedure.

Combined antibiotic therapy spacers either commercial or handmade are superior to monotherapy - a microbiological analysis at the second stage of revision

Background: Antibiotic-loaded spacers are often used during two-stage exchange for periprosthetic joint infections (PJIs) both for its mechanical properties and as a means of local antibiotic delivery. Purpose: The main goal of this study is to compare the efficacy of different options of antibiotic(s) in spacers concerning the rate of positive cultures at the second stage. Patients and Methods: We retrospectively evaluated two-stage exchange procedures for infected hip or knee arthroplasty performed between 2012 and 2018 in which adequate (at least four deep tissue samples) culture results in both stages were available. The type of spacer and antibiotics used, in addition to several other patient, infection and treatment-related variables, were registered and correlated to microbiological findings in the second stage. Results: Fifty-eight cases were included with a 19.0 % (11/58) overall rate of positive cultures during reimplantation. With a mean follow-up of 46 months, failure rate was significantly higher at 63.6 % (7/11) in cases with positive cultures at reimplantation compared to 4.3 % (2/47) for those with negative cultures during reimplantation ( p <  0.001). The need for additional surgeries was also significantly higher (odds ratio (OR) 122.67, confidence interval (CI) 95 % 11.30-1331.32, p <  0.001). Multivariable analysis revealed antibiotics in the spacers were the main independent prognostic risk factor associated with positive cultures at the second stage with an advantage for combined antibiotics. Monotherapy is associated with failure with an OR of 16.99. Longer time between surgeries did not have statistical significance ( p =  0.05), and previous surgical treatment for PJI, presence of difficult-to-treat microorganism(s), duration of systemic antibiotic therapy or even treatment within a dedicated septic team were not shown to be independent risk factors. Among combined antibiotic spacers, there were no significant differences between the rate of positive cultures during the second stage, comparing commercially available vancomycin/gentamicin spacers to hand-mixed vancomycin/meropenem manufactured spacers (8.3 % [2/24] vs. 15.0 % [3/20], p =  0.68). Conclusions: Results show that combined antibiotic therapy spacers are advantageous when compared to gentamicin monotherapy as they produce significantly lower rates of subsequent positive cultures during the second stage. Hand-mixed high-dose vancomycin/meropenem spacers seem to perform just as well as prefabricated commercially available vancomycin/gentamicin options. Level of Evidence: Therapeutic level III.

Complications with cement spacers in 2-stage treatment of periprosthetic joint infection on total hip replacement

INTRODUCTION

The aim of the present study was to assess our management of infected total hip replacement in indications for 2-stage surgical treatment according to current guidelines when a cement spacer has been used. The study hypothesis was that the complications rate related to cement spacers is low.

MATERIAL AND METHOD

A single-center retrospective study included 26 patients receiving a spacer between the two stages of total hip replacement, over a 5 year period. We analyzed the spacers used, mechanical complications, infectious complications and the second stage of surgery.

RESULTS

During the interval between surgeries, in the 26 patients, there were 19 spacer-related mechanical complications (73% of patients): 11 dislocations (42.3%), 5 spacer fractures (19.2%), 5 femoral bone lyses or fractures (19.2%) and 3 acetabular lyses or fractures (11.5%). In 4 cases, complications were associated. The greater the femoral offset of the spacer, the more frequent were femoral bone lyses or fractures (p=0.05), and the smaller the offset the more frequent were acetabular lyses or fractures (p=0.05). The rates of mechanical complications (p=0.003) and spacer fracture (p=0.02) were significantly greater in older patients. There were 4 cases of reinfection (19%): i.e., an 81% treatment success rate. One reinfection implicated a new bacterium: methicillin-susceptible Staphylococcus aureus. The second surgical stage was significantly longer in complex bipolar revision (p=0.009).

CONCLUSION

The present results showed a high risk of spacer-related complications, and thus the importance of selection of patients liable to derive real benefit and those for whom a Gilderstone procedure would be preferable.

LEVEL OF EVIDENCE

IV, retrospective study.