Evaluating Modern Spacer Options and Outcomes in Revision Hip Arthroplasty.

BACKGROUND: A 2-stage revision continues to be the standard treatment for periprosthetic joint infection (PJI) in hip arthroplasty. The use of "functional" spacers may allow patients to return to daily living while optimizing their health for revision surgery. We aimed to evaluate the clinical outcomes of different spacer types regarding infection eradication, mechanical complications, and functional outcomes. METHODS: Patients who have complete Musculoskeletal Infection Society criteria for diagnosis of PJI that underwent one-stage or 2-stage revision were queried in an institutional surgical database between 2002 and 2022. Out of 286 patients, 210 met our inclusion criteria and were retrospectively reviewed for demographics, laboratory values, functional and patient-reported outcomes, and subsequent revisions. The study population had 54.3% women, a mean age of 61 years old, and a mean follow-up of 3.7 ± 3.2 years. There was no difference between age, body mass index, or Charlson Comorbidity Index scores between each cohort. Spacers were categorized as nonfunctional static, nonfunctional articulating, or functional articulating. Functional spacers were defined as those that allowed full weight bearing with no restrictions. Delphi criteria were used to define revision success, and failure was defined as a recurrent or persistent infection following definitive surgery. RESULTS: There was a significantly lower reoperation rate after a definitive implant in the functional articulating cohort (P = .003), with a trending higher infection eradication rate and a lower rate of spacer failure compared to the nonfunctional spacer cohort. At 5 years, functional articulating spacers had a 94.1% survivorship rate, nonfunctional articulating spacers had an 81.2% survival rate, and nonfunctional static spacers had a 71.4% survival rate. In the functional articulating spacer cohort, 14.6% had yet to get reimplanted, with an average follow-up time of 1.4 years. CONCLUSIONS: Within this large cohort of similar demographics, functional articulating spacers may result in better clinical outcomes and infection eradication during 2-stage revision arthroplasty for PJI.

Modern Description of Antibiotic Spacer Options for PJI in Revision Total Knee Arthroplasty: Clinical Outcomes and Infection Eradication Rates.

BACKGROUND: As the burden of periprosthetic joint infections (PJIs) increases, there is growing interest in understanding the efficacy and morbidity reduction of 2-stage revision and various antibiotic spacer options. This study aimed to expand the description and evaluation of spacers from solely their articulation status to include their ability to support full (functional) or partial weight-bearing (nonfunctional). METHODS: Between 2002 and 2021, 391 patients who had Musculoskeletal Infection Society criteria for PJI with 1-stage or 2-stage revision were included. Demographics, functional outcomes, and subsequent revision data were collected. The study population had a mean follow-up of 2.9 years (range, 0.05-13.0) with an average age of 67 years (range, 34.7-93.4). Spacer failure was defined by surgical intervention following definitive surgery, and infection eradication was defined by the Delphi criteria. Spacers were classified as nonfunctional static, nonfunctional dynamic, functional static, or functional dynamic. Two tailed t-tests were performed. RESULTS: There were no significant differences in infection eradication or mechanical outcomes across spacer types; notably, 97.3% of functional dynamic spacers achieved infection eradication. Functional spacers had a longer time to the second stage procedure and a greater number of patients who had not been reimplanted. There was no difference in reoperation rates in nonfunctional versus functional spacers. CONCLUSION: Within this cohort, infection eradication and spacer exchange rates were noninferior among spacers. Functional spacers may allow for earlier return to daily living given the weight-bearing capability when compared to nonfunctional, without sacrificing clinical outcome.

A Retrospective Review of Relative Value Units in Revision Total Knee Arthroplasty: A Dichotomy Between Surgical Complexity and Reimbursement.

BACKGROUND: Revision total knee arthroplasties (TKA) are costly, time-intensive, and technically demanding procedures. There are concerns regarding the valuation of Current Procedural Terminology (CPT) codes and the assigned relative value units (RVU) as a potential disincentive to perform revision TKAs. This study evaluated the labor and time investment for each component-specific revision and assessed the disparities between procedural value billed and reimbursement. METHODS: A retrospective review of 154 primary and revision TKA cases were thoroughly vetted using operative notes and internal billing data. Revision TKAs were stratified by single femoral component, single tibial component, polyethylene liner only, all-component, and spacer placement for prosthetic infection. Operative time, RVUs billed, total charges, deductions, and reimbursements were recorded. Mann-Whitney U tests compared final reimbursement per minute and per RVU between revision and primary TKAs. RESULTS: There were 28 primary TKAs, 11 femoral component revisions, 25 tibial component revisions, 25 liner exchanges, 37 all-component revisions, and 28 spacer placements. Revisions involving the tibial component, all-components, and placement of spacers were reimbursed less dollars per minute than primary TKAs (P < .05). Controlling for RVUs, liner exchanges and all-component revisions had fewer dollars per RVU than primary TKAs (P < .05). CONCLUSION: As revision complexity increases, physicians face less reimbursement per minute and per RVU. With reductions set by CMS and private insurers, revisions may be financially unfavorable and lead to restrictions and access to care problems. Our data supports the need for reevaluating RVU allocation amongst revision procedures with potential updates to the CPT coding system.