High tibial osteotomy improves function and alignment in patients above and below 50 Years: A systematic review

Medial knee osteoarthritis (MKOA) is a debilitating condition frequently affecting younger, active individuals. Medial opening-wedge high tibial osteotomy (HTO) is a joint-preserving surgical technique that realigns the mechanical axis to offload the medial compartment. While traditionally reserved for younger patients, interest is growing in its use among older adults. This systematic review evaluated the functional outcomes of HTO in patients under and over 50 years of age to support age-informed surgical decision-making. Medline, Embase, CINAHL, and Web of Science were searched through December 2024. Inclusion criteria were: (1) mean age reported to allow classification as under or over 50 years, (2) follow-up >12 months, and (3) reporting of validated PROMs after HTO for medial compartment OA. Study quality was assessed using the Methodological Index for Non-Randomized Studies (MINORS), and descriptive statistics summarized findings. Fifteen studies comprising 995 patients were included: 395 under age 50 and 600 aged 50 or older. HTO led to consistent improvements in PROMs across both groups, including Lysholm, IKDC, OKS, and HSS scores, with greater gains typically observed in the younger cohort. Younger patients also demonstrated superior mechanical axis alignment (P ≤ 0.003), higher return-to-sport rates, and more pronounced pain reduction. Radiographic outcomes confirmed reliable correction from varus to neutral or valgus alignment, including improvements in mechanical axis, anatomical femoral-tibial angle, and weight-bearing line ratio. No studies reported deterioration in alignment or PROMs at follow-up. HTO appeared to improve function and alignment in patients under and over 50 years. While younger individuals experienced greater absolute gains, older adults also achieved substantial clinical benefits. These findings support HTO as a joint-preserving option in appropriately selected older patients. Further prospective studies are needed to better define age-related differences in long-term outcomes. IV, systematic review.