Evaluation of Functional Status in Patients after Total Knee Arthroplasty: A Comparison of the Journey II Bi-Cruciate Stabilized Total Knee System and Genesis II Cruciate-Retaining Implant

Background
Total knee arthroplasty (TKA) is an effective treatment for degenerative knee osteoarthritis. The development of new implant designs not only focuses on pain relief but also aims to improve knee function after TKA.

Aim
The aim of this study was to evaluate and compare early functional outcomes after TKA using two different types of prosthesis.

Material and methods
Patients who underwent TKA with the Journey II Bi-cruciate Stabilized (JII BCS) Total Knee System (n = 9) and Genesis II Cruciate-Retaining (GII CR) implant (n = 9) were included in the functional evaluation. Active range of motion (AROM) was measured. Anterior tibial translation was measured using an electromechanical arthrometer, while single-leg stance performance was assessed using a balance platform. The Western Ontario and McMaster Universities Osteoarthritis (WOMAC) questionnaire was used for the assessment of subjective functional outcomes.

Results
The arthrometry result showed a significant difference of (−)0.2mm between the operated and non-operated extremities in the JII BCS group and 2.3 mm in the GII CR group. The single-leg balance test result showed a significant difference in overall stability index of 2.7° for the JII BCS group and 4.6° for the GII CR group. Both the AROM and WOMAC scores were higher in the JII BCS group.

Conclusions
Compared with the GII CR implant, the JII BCS implant provided better functional outcomes of the anterior and posterior cruciate ligaments in patients in the early phase after TKA.