Anatomically‐designed bicruciate‐retaining total knee arthroplasty demonstrates good two‐year survivorship and improvements in patient‐reported outcomes: A prospective multicenter single‐arm study

TL;DR

A new knee implant design showed good survival and improved patient outcomes over two years in a clinical study.

Contribution

The study introduces a novel anatomical bicruciate-retaining knee implant and confirms its early safety and effectiveness.

Findings

The implant had a 97.9% survivorship at 2 years, meeting non-inferiority criteria.

Patient-reported outcomes showed significant and clinically meaningful improvements over time.

Radiographic findings indicated stable implant performance with reduced radiolucent lines.

Abstract

To evaluate the early safety and performance of a novel anatomical‐design bicruciate‐retaining total knee arthroplasty (BCR‐TKA) implant (JOURNEY™ II XR; JIIXR) in a prospective multicenter single‐arm cohort, with 2‐year implant survivorship as the prespecified primary endpoint, and patient‐reported outcomes and radiographic findings as secondary exploratory endpoints.

Ninety‐four patients (106 knees) underwent cemented BCR‐TKA with JIIXR at eight centers. The primary endpoint was 2‐year survivorship tested for noninferiority versus a 98% benchmark using exact binomial (one‐sided 97.5% CI) and Kaplan–Meier methods. Secondary endpoints included the EuroQol 5‐Dimension 5‐Level (EQ‐5D‐5L) questionnaire, its visual analogue scale (EQ‐VAS), Forgotten Joint Score‐12 (FJS‐12, collected postoperatively only), Knee Injury and Osteoarthritis Outcome Score (KOOS), range of motion, and radiolucent lines assessed in standardized zones.

At 2 years, survivorship was 97.9% (94/96), confirming non‐inferiority (p = 0.0064). Patient‐reported outcome measures improved over follow‐up: EQ‐VAS increased from 62.0 preoperatively to 83.7 at 2 years; EQ‐5D‐5L index from 0.61 to 0.84; and KOOS pain and symptoms from 52.8 and 59.2 to 87.9 and 84.6, respectively. FJS‐12 increased from 40.0 at 3 months to 65.4 at 2 years. Across measures, the changes exceeded published minimally clinically important differences (MCIDs): all KOOS subscales met MCID by 1 year, EQ‐VAS exceeded MCID by 3 months, and FJS‐12 exceeded MCID between 3 months and 1 year. Radiolucent lines were observed in 35 knees (36.5%); total length decreased from 5.1 ± 6.7 mm at 3 months to 2.6 ± 2.3 mm at 2 years with no radiographic loosening. Range of motion at 2 years was similar to baseline.

In this prospective single‐arm multicenter study, an anatomical‐design BCR‐TKA implant achieved good 2‐year survivorship and clinically meaningful improvements in patient‐reported outcomes, with stable radiographic findings. These data support early safety and performance while underscoring the need for long‐term comparative studies to establish durability and relative effectiveness.

Level II, therapeutic study.

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