Short-Term functional comparison of three total knee arthroplasties-Journey II, Genesis II and Profix.

AIM OF THE STUDY: To compare the outcomes of three knee arthroplasty design philosophies and surface tribology.• A zirconium-surfaced, bicruciate-stabilised implant designed to mimic kinematic movement and improve flexion and outcomes;• A cobalt-chrome surfaced, multi-radius design with built-in femoral external rotation to aid balancing and patella tracking through a deeper trochlea groove;• A zirconium-surfaced, single-radius implant designed on surface conformity, particularly within the patello-femoral joint. METHODS: 313 knee replacements - 103 Journey II, 103 Genesis II and 107 Profix - were statistically assessed at a minimum of 2 years using WOMAC, Oxford and SF-12 scores, and range of movement. RESULTS: There was no difference between the actual or unit change in WOMAC scores (p = 0.140 and p = 0.287), SF-12 physical (p = 0.088) or mental scores (p = 0.975) between the three implants; or between the actual or unit change in Oxford score (p = 0.912 and p = 0.874) for the Journey II or Genesis II. The Journey II produced more flexion and range of movement than the Genesis II (p < 0.001 and p = 0.018) and Profix (p < 0.001 and <0.001) with no difference between the latter two (p = 0.402 and 0.568); with no difference in extension between the three implants (p = 0.086). There was no difference between those with or without a resurfaced patella. CONCLUSION: The three design philosophies and surfaces yielded no difference in outcome scores at 2 years post-operatively. The Journey II demonstrated better post-operative flexion. Resurfacing the patella did not alter the outcome scores or flexion.

The Journey Bicruciate Knee Replacement: Design Modifications Yield Better Early Functional Results and Reduce Complications.

The Journey-I total knee replacement was designed to improve knee kinematics but had several complications including early dislocation. The Journey-II modification was introduced to reduce these while maintaining high function. To assess whether the modified Journey-II prosthesis has succeeded in its designers aims, we undertook an observational study of prospectively recorded data to analyze and compare the two knees. A total of 217 Journey-I and 129 Journey-II knees were identified from the department's prospectively collated registry and were assessed at 1 year by a comparative statistical analysis using numerous factors including pain, functional activity, physical assessment, Short Form-12 (SF-12), Western Ontario and McMaster Universities Arthritis Index (WOMAC), and Oxford scores. The statistical tests included Chi-square, Wilcoxon's rank and Mann-Whitney U-tests with the level of significance set at p < 0.05. There was a variation in primary patella resurfacing between the two groups with 14.3% in the Journey-I cohort and 66.7% in the Journey-II cohort. Both replacements demonstrated excellent postoperative function, but the Journey II performed significantly better than Journey I with fewer complications (37 vs. 10) and better improvement in almost all clinical scores including pain (p < 0.01), mobility outcomes (p = 0.018), Oxford (p = 0.004), and WOMAC (p = 0.039) scores but not with flexion improvement and SF-12 score. There was significant improvement in patellofemoral pain postoperatively in both the Journey I (p = 0.011) and Journey II (p = 0.042) arthroplasty; however the primarily resurfaced patella in a Journey-II implant had better postoperative scores. The main complication of dislocation in the Journey I was not seen in the modified Journey-II implant with stiffness requiring intervention reduced in Journey II. These results suggest that the Journey II has improved short-term clinical outcomes compared with Journey I with reduction of dislocation and other complications.