Randomised controlled trials (RCTs) or observational studies that compared high tibial osteotomy and medial UKA for isolated medial compartment osteoarthritis were eligible for inclusion, provided they reported as outcomes the rate of good or excellent results (primary outcome), implant survivorship and/or postoperative gait velocity. Using the Knee Society Scoring System, good or excellent results were defined as a score of at least 70. Survivorship was defined as freedom from surgical revision.
The mean age of participants in the included studies ranged from 55 to 71 years. Males comprised 21% to 86% of participants. A wide variety of implants were used in the UKA group, while for high tibial osteotomy most studies used a lateral closing wedge technique. Good or excellent results were in most cases defined by subjective study-specific measures rather than Knee Society Scoring System. Implant survivorship was reported in the review in terms of no aseptic loosening. Some studies commented on surgical complications. Mean duration of follow-up ranged from 0.5 to 7.8 years; however, it was stated that mean follow-up for the primary review outcome was at least two years in all cases.
Two authors independently selected the studies for inclusion.