Unicompartmental knee arthroplasty for the treatment of unicompartmental osteoarthritis: a systematic study

Unicompartmental knee arthroplasty (UKA), total knee arthroplasty (TKA) and high tibial osteotomy (HTO) may all be used to treat unicompartmental osteoarthritis, but they are often used for different patient groups. However, there is considerable overlap in indications for all three options. The aim of this review was to assess the safety and efficacy of UKA compared with TKA and HTO in unicompartmental osteoarthritis. Studies that compared UKA with either TKA or HTO were identified and included for review. For knee function and postoperative pain, UKA appeared similar to TKA and HTO at 5 years follow up. Range of motion was better in UKA compared with TKA. Complication rates after UKA and TKA appeared similar, although deep vein thrombosis was reported more often after TKA. There were more complications after HTO than UKA. Survival of UKA prostheses was approximately 85-95%, compared with at least 90% for TKA at 10 years follow up. Survivorship for HTO appeared to be less than 85%. It was not clear whether there were more revisions after UKA than TKA, but there appeared to be fewer revisions in UKA compared with HTO. UKA is considered at least as safe as TKA and HTO. For function, UKA appears to be at least as efficacious as TKA and HTO. The survival of UKA compared with TKA and HTO cannot be determined based on the available evidence.