Indications and outcomes in bi-unicondylar knee arthroplasty: A systematic review.

PURPOSE

The aim of this systematic review is to analyze and provide an overview of the indications, contraindications and the clinical outcomes to bi-unicondylar knee arthroplasty (Bi-UKA).

METHODS

A comprehensive search was conducted to identify original studies written in English reporting indication criteria or clinical outcomes on Bi-UKA) performed simultaneously or at two different stages. Studies reporting patellofemoral implants with medial or lateral implants, ex-vivo or cadaveric studies were excluded. The study was carried out in accordance with PRISMA guidelines, with the search covering studies up to February 2025.

RESULTS

The literature search identified 783 articles, nine of which were included in this review. A total of 343 patients were identified, of which 257 patients underwent bi-UKA. Medial and lateral osteoarthritis (OA) are the main indications for Bi-UKA. The condition of the anterior cruciate ligament (ACL) was taken into consideration by eight studies and 49 patients (19.02%) presenting functional or macroscopic intact ACL were eligible for Bi-UKA. Age was considered as an eligibility criterion in one study alone. In all studies, Bi-UKA led to the improvement of clinical scores compared to their pre-operative values.

CONCLUSIONS

Both staged and simultaneous Bi-UKA are viable options to treat knee osteoarthritis. However, further research is needed to better investigate bi-UKA.

LEVEL OF EVIDENCE

Level III.