Posterior-stabilized versus cruciate-retaining total knee arthroplasty: balancing the gap

Area of Science:

• Orthopaedic Surgery
• Biomedical Engineering
• Clinical Trials

Background:

• Total knee arthroplasty (TKA) is a common procedure for end-stage knee osteoarthritis.
• Cruciate-retaining (CR) and posterior-stabilized (PS) designs are prevalent TKA options.
• Comparative effectiveness data between CR and PS TKA designs remain important for surgical decision-making.

Purpose of the Study:

• To compare the clinical, functional, and radiographic outcomes of cruciate-retaining (CR) versus posterior-stabilized (PS) total knee arthroplasties (TKAs).
• To evaluate the impact of surgical technique and joint balancing on TKA outcomes.

Main Methods:

• A prospective, randomized, double-blind trial involving 40 knees undergoing TKA.
• Randomization to either NexGen CR or Legacy PS TKA (Zimmer).
• Standardized surgical technique with precise balancing of flexion-extension gaps.

Main Results:

• No statistically significant differences were observed between CR and PS TKAs at the 2-year follow-up.
• Knee Society clinical, functional, and radiographic scores were comparable between the two TKA designs.
• Surgical technique and joint balancing were emphasized as critical factors.

Conclusions:

• Both CR and PS TKAs yield similar patient outcomes when implanted with meticulous surgical technique and attention to joint balancing.
• Orthopaedic surgeons can expect comparable results regardless of choosing a CR or PS TKA design.
• Further long-term studies may elucidate subtle differences, but current evidence supports equivalent short-term efficacy.