The Efficiency and Cost‐Effectiveness of 3D ‐Printed Patient‐Specific Guide Plate for Patients Undergoing Open‐Wedge High Tibial Osteotomy: A Multicentered Randomized Controlled Trial

PURPOSE: Open-wedge high tibial osteotomy (OWHTO) is established for young, active patients with medial knee osteoarthritis. Patient-specific 3D-printed guide plates have been introduced to improve surgical precision and efficiency, but evidence of clinical and economic benefit is limited. We aimed to determine whether a 3D-printed patient-specific guide plate improves efficiency, functional outcomes, and cost-effectiveness compared to standard OWHTO. METHODS: In this multicenter randomized trial, patients scheduled for OWHTO were allocated to either conventional planning (control) or surgery using a patient-specific 3D-printed guide plate between November 2020 and June 2024. The primary endpoint was the 12-month Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score. Secondary outcomes included knee range of motion (flexion in degrees), 30-s chair-stand test (number of stands), operative time, and health economic measures (direct costs and quality-adjusted life years). Analyses were by intention-to-treat using appropriate statistical tests. RESULTS: A total of 180 patients (mean age 55 years, 56.7% male) were randomized equally between groups. At 12 months, mean WOMAC pain was 15.2 (SD 8.4) in the guide-plate group and 15.6 (SD 8.7) in controls, with no significant difference (p = 0.74). The guide-plate group showed significantly greater knee flexion (mean 128° vs. 122°; p = 0.04) and a higher 30-s chair-stand count (14.2 vs. 12.5 stands; p = 0.02) than controls. There were no other significant between-group differences in clinical scores. Mean total cost per patient was not statistically significant in the ITT analysis (p = 0.094). Quality-adjusted life years did not differ between groups, yielding no cost-effectiveness advantage. These findings echo prior reports that OWHTO techniques with higher costs have similar patient outcomes. CONCLUSION: Using a 3D-printed patient-specific guide plate did not improve the primary pain outcome or overall functional outcome compared to standard OWHTO. It yielded minor gains in knee flexion and chair-stand performance, but at greater cost. No overall cost-effectiveness benefit was observed. Routine use of this technology for OWHTO is not supported by our findings. LEVEL OF EVIDENCE: Level I, randomized controlled trial. TRIAL REGISTRATION: Chinese Clinical Trial Registry (https://www.chictr.org.cn/): ChiCTR2000038619.