Posterior-stabilized and cruciate-retaining total knee replacement: a randomized study

Area of Science:

• Orthopedic surgery
• Biomedical engineering
• Clinical research

Background:

• Total knee replacement is a common procedure for osteoarthritis.
• Implant design, specifically posterior-stabilized versus cruciate-retaining, may influence outcomes.
• Patient selection criteria are crucial for comparable study groups.

Purpose of the Study:

• To compare clinical, radiographic, and quality of life outcomes between posterior-stabilized and cruciate-retaining primary total knee implants.
• To evaluate the efficacy of different total knee arthroplasty designs in patients with osteoarthritis and an intact posterior cruciate ligament.

Main Methods:

• A randomized controlled study enrolled 143 patients (57-89 years) with osteoarthritis.
• Patients were randomized to posterior-stabilized (n=76) or cruciate-retaining (n=67) AMK total knee implants.
• Follow-up included 2-year (n=108) and 3-year (n=73) assessments of clinical outcomes using the Knee Society score and range of motion.

Main Results:

• At 2 years, the Knee Society clinical rating scores were similar: 157.1 (posterior-stabilized) vs. 156.5 (cruciate-retaining).
• At 3 years, scores were 156.8 (posterior-stabilized) vs. 163.5 (cruciate-retaining).
• Range of motion at 2 years was 113.6° (posterior-stabilized) vs. 108.5° (cruciate-retaining); at 3 years, 108.5° vs. 108.3°, respectively. No notable differences were observed between implant types at either time point.

Conclusions:

• No significant differences in clinical outcomes were found between posterior-stabilized and cruciate-retaining total knee implants at 2-year follow-up.
• This trend of comparable outcomes persisted at the 3-year follow-up.
• Both implant designs appear to offer similar efficacy for primary total knee replacement in carefully selected osteoarthritis patients.