Factors affecting postoperative flexion in total knee arthroplasty

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Rehabilitation Medicine

Background:

• Total condylar (TC) knee prostheses are commonly used in knee replacement surgery.
• Optimizing postoperative knee flexion is crucial for patient function and satisfaction.
• Various prosthetic designs and surgical techniques aim to enhance range of motion.

Purpose of the Study:

• To investigate factors influencing postoperative knee flexion in patients with total condylar (TC) prostheses.
• To evaluate the impact of different prosthetic designs and surgical techniques on flexion outcomes.
• To identify key elements for maximizing knee range of motion after surgery.

Main Methods:

• Review of 67 cases with TC prostheses, 59 with TC posterior stabilizers, 70 with TC prostheses modified with flat posterior tibial plateau, and 35 with porous-coated arthroplasty (PCA) prostheses.
• Cross-examination of multiple factors affecting postoperative flexion.
• Follow-up period ranging from 2 to 9 years.

Main Results:

• No significant improvement in flexion was observed after 1 year post-surgery in most cases.
• Intense physical therapy, promoting suprapatellar pouch reconstitution, was the most influential factor for good postoperative flexion.
• Retaining the posterior cruciate ligament (PCL) was associated with increased residual flexion contracture in cases with preoperative contracture.
• Preoperative anterior cruciate ligament (ACL) condition and PCL retention did not significantly impact ultimate flexion.

Conclusions:

• Postoperative knee flexion is primarily influenced by the intensity of physical therapy and suprapatellar pouch status.
• Prosthetic design variations and PCL management require careful consideration, especially in patients with preoperative flexion contracture.
• Early and aggressive rehabilitation is essential for achieving optimal flexion outcomes following TC knee arthroplasty.