Can tibia-first total knee arthroplasty using computer-assisted system improve anterior and posterior knee stability?

Abstract

BACKGROUND: Total knee arthroplasty (TKA) is a widely performed procedure to alleviate pain and restore function of patients with end-stage knee osteoarthritis. OBJECTIVE: The study aim was to determine if tibia-first (TF) total knee arthroplasty (TKA) using a novel computer-assisted surgery (CAS) system can yield better anterior and posterior (AP) knee stability. METHODS: Patients with knee osteoarthritis with obvious varus knee who met the indication for and underwent TKA from May 2019 to November 2020 were included. Forty-one measured resection (MR)-TKAs and 32 TF-TKAs were compared. The varus-valgus ligament balance and joint tension at a joint center-gap setting equal to the tibial-baseplate thickness were measured, and appropriate polyethylene inserts with 0∘, 30∘, 45∘, 60∘, 90∘, and 120∘ of knee flexion were placed. A Kneelax 3 arthrometer was used to measure knee AP laxity in the postoperative anesthetized patients with 30∘ and 90∘ of knee flexion. RESULTS: The horizontal gap balance was significantly closer in the TF-TKA group than the MR-TKA group for 0∘, 30∘, 45∘, and 60∘ of knee flexion. In contrast, no significant differences were observed for 90∘ and 120∘ of knee flexion. No significant differences in joint-gap tensions among all knee-flexion angles were observed. Translation was significantly smaller in the TF-TKA group than the MR-TKA group for AP laxity with 30∘ of knee flexion (8.8 ± 2.9 mm vs. 10.7 ± 3.1 mm, P= 0.0079). In contrast, no significant AP laxity was observed with 90∘ of knee flexion (7.2 ± 2.8 mm vs. 7.2 ± 3.5 mm). CONCLUSION: TF-TKA using a novel CAS system provided better AP knee stability with close to horizontal gap balances.

Relationship Between Intraoperative Macroscopic Anterior Cruciate Ligament Findings, Perioperative Surgical Findings, and Postoperative Clinical Outcome After Cruciate-Retaining Total Knee Arthroplasty

“…TKA was performed in all cases using a midvastus approach with a cemented implant of CR; ACL was dissected in all cases with the posterior cruciate ligament (PCL) retained. None of the patients underwent patellar resurfacing [ 9 ]. Mechanical alignment TKA was performed to obtain a mechanically neutral coronal mechanical limb alignment by cutting the femur and tibia so that the rectangular flexion and extension gaps were perpendicular to the mechanical axis.…”

“…This test was performed at 30° and 90° knee joint flexion upon awakening (Figure 1 ). One senior surgeon performed the AP drawer test and applied a force of 132 N to the tibia against the femur in the anteroposterior direction; the total AP laxity was calculated and recorded [ 9 ]. Additionally, ROM of knee extension and flexion was examined.…”