Unicompartmental knee arthroplasty: a controversial history and a rationale for contemporary resurgence.

Treatment of isolated compartment osteoarthritis with unicompartmental knee arthroplasty (UKA) has had mixed reported results and still remains a controversial procedure. More recently, adherence to more stringent patient selection criteria and refined surgical technique has resulted in improved clinical outcomes and survivorship. The popularization of UKA as a more tissue-sparing procedure and minimally invasive alternative to total knee arthroplasty has also played an integral role in its recent resurgence. This review details the history, evolution, and varied results of UKA. Many different prostheses have emerged, some with exceptional long-term results. Long-term prospective analyses will be critical in determining the role of UKA as a mainstay in the treatment of single compartment knee degenerative joint disease.