Partial vs Total Knee Replacement: ROM & Satisfaction Key in New Orleans Study

Patients considering knee replacement may find that a partial knee replacement offers greater satisfaction and a better range of motion compared to a total knee replacement, according to findings presented at the American Academy of Orthopaedic Surgeons (AAOS) Annual Meeting in Fresh Orleans this week. Even as partial knee replacements demonstrated a higher reoperation rate, the benefits in patient-reported outcomes are prompting surgeons to carefully weigh the options with patients who have arthritis primarily affecting one compartment of the knee.

Weighing the Options: Partial vs. Total Knee Replacement

The research, led by Craig J. Della Valle, MD, of Rush University Medical Center, analyzed data from 105 knees – 56 that underwent partial knee arthroplasty and 49 that received total knee arthroplasty. The study followed patients for an average of nearly five years, assessing implant survivorship, revision rates, and patient-reported outcomes using the Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) and Knee Society Scores. Details of the study were presented at the AAOS meeting.

The findings revealed a higher reoperation rate in the partial knee arthroplasty group. However, KOOS JR and Knee Society Scores were comparable between the two groups. Notably, patients who received a partial knee replacement reported a greater range of motion and higher overall satisfaction.

“If you observe a patient who has anteromedial arthritis, they have predominantly arthritis of the medial compartment with an intact ACL and a pretty normal feeling knee with good range of motion, both partial and total knee replacement are good options and reasonable options,” Dr. Della Valle told Healio. “But I would still err on the side of partial knee replacement given the higher patient satisfaction and higher range of motion. My perspective is if the results are pretty similar, why wouldn’t you do the smaller operation?”

Understanding Partial and Total Knee Replacement

Knee replacement surgery aims to relieve pain and restore function in a damaged knee joint. Total knee replacement involves replacing the entire knee joint with artificial components. Partial knee replacement, also known as unicompartmental knee arthroplasty, replaces only the damaged compartment of the knee – typically the medial (inner) compartment – while preserving the healthy cartilage and ligaments.

The decision between partial and total knee replacement depends on several factors, including the extent of arthritis, the patient’s activity level, and the stability of the knee. Partial knee replacement is generally considered for patients with arthritis limited to one compartment of the knee, good ligament stability, and adequate range of motion. Johns Hopkins Medicine provides a detailed overview of knee replacement options.

The Trade-offs: Reoperation Rates and Patient Outcomes

The higher reoperation rate observed in the partial knee arthroplasty group in Dr. Della Valle’s study is a known consideration. Partial knee replacements can sometimes fail due to progression of arthritis into other compartments of the knee, requiring conversion to a total knee replacement. However, the study highlights that even with this risk, the benefits in range of motion and patient satisfaction can be significant for appropriately selected patients.

“We confirmed that if you are choosing between a partial and total knee replacement, if range of motion is something that is vital for the patient, a partial knee may be a better choice,” Dr. Della Valle explained.

Long-Term Follow-Up and Future Research

The researchers plan to continue following these patients to assess the long-term outcomes of both procedures. “We looked at an average of just under 5 years. I want to look at these same patients in 5 more years and understand what they look like then,” Dr. Della Valle stated. Long-term data will be crucial to fully understand the durability and overall value of partial versus total knee replacement.

Implications for Patient Care

These findings reinforce the importance of a thorough evaluation and shared decision-making process between surgeons and patients considering knee replacement. Patients should discuss their individual circumstances, activity goals, and preferences with their surgeon to determine the most appropriate surgical option.

The study also underscores the value of patient-reported outcome measures in evaluating the success of knee replacement surgery. While implant survivorship and revision rates are important indicators, patient satisfaction and functional outcomes are equally critical in determining the overall benefit of the procedure.

Further research is needed to identify the optimal patient selection criteria for partial knee replacement and to develop strategies to minimize the risk of reoperation. Ongoing clinical trials and data registries will play a vital role in advancing our understanding of these procedures and improving outcomes for patients with knee arthritis.