Rotating-platform deep-dish total knee arthroplasty with restricted kinematic alignment: Five-year clinical and functional outcomes.

INTRODUCTION

Total knee arthroplasty (TKA) utilizing deep-dish tibial inserts has gained interest due to its high congruency and enhanced stability. However, due to the advent of more personalized alignment philosophies, the combination of a rotating-platform deep-dish TKA design with restricted kinematic alignment (rKA) might improve patient satisfaction. Therefore, this study evaluated the five-year clinical and functional outcomes of rKA with a deep-dish TKA design.

METHODS

A retrospective analysis was conducted on patients who underwent primary TKA with a rotating-platform deep-dish design and rKA. Of 143 eligible patients, 123 completed five-year follow-up. Clinical and radiographic assessments included the five-year postoperative results: Knee Society Score (KSS), patient satisfaction, range of motion, coronal limb and implant alignment, postoperative complications and implant survivorship. Statistical analyses compared preoperative and postoperative outcomes with paired analyses.

RESULTS

Median KSS Knee and Function scores significantly improved from 70 (IQR 5) and 60 (IQR 26) preoperatively to 90 (IQR 20) and 93 (IQR 21) postoperatively (p < 0.001). Postoperative coronal alignment in this study encompassed a hip-knee-ankle angle was 178.1° ± 3.5, a Lateral Distal Femoral Angle of 89.9° ± 2.6, and a Medial Proximal Tibial Angle of 88.6° ± 2.2. At five years, 94% of patients were either satisfied or very satisfied. The revision-free survival rate was 98%. Periprosthetic joint infection and arthrofibrosis were the most common complications (1.6% for both groups separately), followed by aseptic loosening of a cementless femoral component (0.8%) and patellar dislocation (0.8%).

DISCUSSION

Rotating-platform deep-dish TKA with restricted kinematic alignment results in excellent functional outcomes, high patient satisfaction, and low complication rates at five-year follow-up. These findings support its viability as a surgical strategy, though long-term studies are warranted to assess implant durability and survivorship beyond 10 years.