Unicompartmental knee arthroplasty – surgical choice for the treatment of medial osteoarthritis of the knee: indications, contraindications, outcomes.

Armandas Šležas1

1Faculty of Medicine, Vilnius University, Vilnius, Lietuva

Abstract

Knee osteoarthritis is one of the most common degenerative diseases affecting the joint. Medial osteoarthritis of the knee or combined lesion of several compartments is the most common in clinical practice, so it is important to know the pathophysiology, diagnosis and treatment methods of this disease. When osteoarthritis is diagnosed before it has progressed, a wider range of treatment options opens up. One of these options is a unicompartmental knee arthroplasty.

Aim: to review epidemiology, pathophysiology, classification, diagnosis, treatment of the medial knee osteoarthritis and indications, contraindications, complications, and outcomes of the unicompartmental knee arthroplasty.

Materials and methods: literature review was performed using PubMed database, selecting publications in English, by keywords and their combinations: unicompartmental knee arthroplasty, medial osteoarthritis of the knee, total knee arthroplasty, outcomes, indications, contraindications. Efforts have been made to focus on publications from the last 5 years, but the citation period has not been limited.

Results: this literature review provides the analysis of 46 studies. Isolated medial osteoarthritis of the knee is diagnosed in more than 25% of cases. Long-term survival rate of a unicompartmental knee replacement is 70% to 94%. The survival of cementless unicompartmental implants over a period of 5 years is 90-99% and cemented implants – 91-95%. Mortality during the 90-day period after unicompartmental knee arthroplasty is up to 0.4% and after total knee arthroplasty – 0.24-0.7%. In the long-term postoperative period, revision rates of unicompartmental knee arthroplasty are 14.6-21%. The most common causes of revision surgery are aseptic loosening, progression of osteoarthritis, pain, joint instability, or infection.

Conclusion: compared to total knee arthroplasty, unicompartmental knee arthroplasty has faster recovery after surgery, better functional outcomes, less invasive surgery, fewer complications, but narrower indications and higher rates of revision.

Keywords: unicompartmental knee arthroplasty, medial osteoarthritis of the knee, total knee arthroplasty, outcomes, indications, contraindications.