Year: 2024
Type: article
Abstract: INTRODUCTION: In 2019, a new fixed-bearing implant for unicondylar knee arthroplasty (UKA) was introduced that incorporated a round-on-flat design featuring an Oxinium femoral component coupled with a highly crosslinked polyethylene bearing surface. Compared to prior implants, the design featured smaller size increments coupled with medial and lateral-specific tibial baseplates. The objective of this study is to describe our institution's early experience with this UKA implant system by evaluating survivorship, reasons for revision, and patient-reported outcome measures (PROMs). METHODS: . Outcome measures included Kaplan-Meier survivorship using reoperation for any reason as an endpoint, reasons for reoperation, range of motion, and PROMs that were collected preoperatively and postoperatively at 4 weeks, 4 months, 1 year, and 2 years. RESULTS: Using reoperation for any reason as an endpoint, 1-year survivorship was 99.3% (95% CI, 98.7 to 99.9%) and 2-year survivorship was 98.2% (95% CI, 96.9 to 99.5%). There were nine reoperations among the 944 UKAs, including three for infection, two for tibial loosening, one for femoral loosening, one for progression of arthritis, one for patellar instability, and one for recurrent hemarthrosis. The mean time to reoperation was 0.82±0.68 years and all were performed among medial UKAs. Range of motion increased from 117±8 degrees preoperatively to 122±6 degrees at 1-year follow-up. PROMs, including the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) and the Patient-Reported Outcomes Measurement Information System (PROMIS) Global Health Physical score, demonstrated progressive increases from the preoperative assessment through 2-year follow-up. For UKAs with preoperative and 2-year KOOS JR scores, the mean change was 31±17. CONCLUSION: As new implants and technologies are introduced, documenting the early outcome from high volume centers can offer valuable insights to validate the effectiveness of implant systems before they are adopted by the broader orthopedic community. This study demonstrates encouraging early outcome data associated with a contemporary UKA system based on survivorship and PROMs. At this early stage, there are no implant-related concerns but obtaining additional follow-up will be important to quantify how revisions and PROMs evolve over time.
Source: Cureus
DOI: 10.7759/cureus.74596
Authors: Kevin B Fricka, Alexander V Strait, Henry Ho, Robert H Hopper, Craig J McAsey
Language: English
Subfield: Surgery
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W4404790386