Bicruciate-retaining total knee arthroplasty: What’s new?

Abstract

Primary total knee arthroplasty (TKA) is a widespread procedure to address end stage osteoarthritis with good results, clinical outcomes, and long-term survivorship. Although it is frequently performed in elderly, an increased demand in young and active people is expected in the next years. However, a considerable dissatisfaction rate has been reported by highly demanding patients due to the intrinsic limitations provided by the TKA. Bicruciate-retaining (BCR) TKA was developed to mimic knee biomechanics, through anterior cruciate ligament preservation. First-generation BCR TKA has not gained popularity due to its being a challenging technique and having poor survival outcomes. Thanks to implant design improvement and surgeon-friendly instrumentation, second-generation BCR TKA has seen renewed interest. This review will focus on surgical indications, kinematical basis, clinical results and latest developments of second-generation BCR TKA.

Bicruciate-Retaining Total Knee Arthroplasty: State of the Art for the Younger and Active Population? A Systematic Review and Future Prospective

“…First-generation BCR-TKA, for which the longest follow-up is available, included a femoral component with cobalt-chromium with an asymmetric trochlear groove requiring right and left components. The tibial component consisted of a flat symmetric polyethylene (PE) insert on a single-piece horseshoe-shaped titanium tibial tray with two round fixation pegs and a flat symmetric polyethylene (PE) bearing [4]. Pritchett presented the largest case series (214 arthroplasties in 160 patients) for this implant (Townley Anatomic, Biopro Inc, Port Huron, MI, USA) with clinical outcomes with a minimum follow-up of 20 years [11].…”

“…Second-generation models were designed to improve implant stability based on an asymmetric-anatomical-or non-anatomical-perimeter-shaped tibial component with better tibial fixation and anterior stability [4].…”

“…The Journey II XR (Smith and Nephew plc, Watford, United Kingdom) system was designed to overcome ongoing concerns of loosening and improve kinematics. The design consists of an anatomical tibial component that includes a metal tibia tray with two independent and uniquely designed concave medial and convex lateral bearings together with a natural 3 • oblique joint line [4]. One kinematic clinical study in 17 knees of 15 patients found the in vivo kinematics of BCR-TKA knees reproduced native knee kinematics to a lower extent compared 20 patients that received unicompartimental knee arthroplasty (UKA) [25].…”

“…To date, the lack of improved clinical outcome and implant survival after BCR-TKA along with the low methodological quality of clinical trials have restricted broad implementation. Still, the proposed clinical and kinematic improvement that may be achieved by retaining the ACL has been supported by different kinematic and laboratory studies, along with early results of clinical trials [4]. The increase in the use of robotic-assisted TKA may further improve optimal implant placement, ligament balancing and alignment that may prove to be key factors in its possible success.…”

“…Primary TKA was designed to sacrifice the anterior cruciate ligament (ACL) and gain anteroposterior (AP) stability from the implant design in either posterior-cruciate-retaining (CR) or posterior-stabilized (PS) knee arthroplasties. The resulting loss of propriocepsis, along with the paradoxical anterior femoral translation commonly observed in mid-and terminal flexion, may lead to suboptimal kinematics and eventually to patient dissatisfaction [4][5][6][7][8]. Thus, in retaining the cruciate ligaments, bicruciate (BCR)-TKA may improve kinematics and lead to improved clinical outcome in the higher-demanding patients.…”