A "1.5-Stage" Spacer Construct Using Revision Components for the Management of Periprosthetic Joint Infection of the Knee

Background: The two-stage surgical protocols used for the treatment of periprosthetic joint infection following total knee arthroplasty are associated with marked patient morbidity. As such, alternatives, such as durable "1.5-stage" spacer constructs, have gained popularity. We sought to describe the outcomes of a novel "1.5-stage" spacer construct utilizing revision stemmed-tibia implants. Methods: Patients who underwent a "1.5-stage" for the management of a knee periprosthetic joint infectionat our institution were screened for inclusion. A "1.5-stage" was defined as a spacer placed with the intent of not performing a second stage, without the use of press-fit stems or cemented intramedullary fixation as is often done during a single-stage protocol. Procedures were categorized into two groups based on construct type: (1) hand-made constructs utilizing all-polyethylene tibial components; or (2) constructs utilizing stemmed-revision components precoated with cement before insertion. Patient demographics, comorbidities, and surgical details were collected and reported. The two-year Kaplan-Meier survival estimates for all-cause revision, revision for spacer loosening, and revision due to infection recurrence were reported. In total, 46 "1.5-stage" procedures were identified, including 12 handmade and 34 stemmed-revision constructs. Results: The stemmed-revision cohort was less likely to undergo reoperation for any reason (17.6 versus 50.0%, P = 0.028) or a revision for spacer loosening (0.0 versus 25.0%, P = 0.003) compared to the handmade cohort. There were no differences with respect to infection recurrence or time to revision. The 2year survival from revision for loosening was higher in the stemmed cohort compared to the handmade cohort though not statistically different (100%, 95% CI [confidence interval]: 2.5 to 100.0 versus 72.9%, 95% CI: 26.3 to 96.6%, P = 0.330). Conclusions: A "1.5-stage" spacer construct using stemmed-revision components was associated with promising short-term results. Durable spacer constructs may be a viable option for select patients; however, longer-term follow-up is needed to identify patients who stand to benefit the most from this technique. (c) 2025 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.