Comparison of a patient-specific instrument and conventional high tibial Osteotomy: Accuracy of correction target and prevention of posterior tibial slope change.

Abstract

High tibial osteotomy (HTO) is crucial for managing medial compartmental knee osteoarthritis. Precision in achieving the medial proximal tibial angle (MPTA) correction and maintenance of posterior tibial slope (PTS) is essential for clinical success. This study aims to compare the use of 3D-printed patient-specific instruments (PSI) to conventional HTO to achieve precise MPTA correction and maintenance of PTS, aiming to enhance surgical outcomes in HTO patients. Among 104 patients who underwent HTO between September 2018 and July 2021, 60 met the inclusion criteria and were categorized into a PSI group (30 cases) and conventional method group (30 cases). Radiological outcomes included estimated and postoperative MPTA values, along with preoperative and postoperative PTS measurements. Within the conventional HTO group, significant differences were noted between the estimated and postoperative MPTA values (94.3° ± 2.4° vs. 93.5° ± 2.5°, <i>P</i> = 0.023), as well as between the preoperative and postoperative PTS values (8.8° ± 3.2° vs. 7.9° ± 3.5°, <i>P</i> = 0.033). Conversely, the PSI group did not exhibit any significant differences in these values. This study indicated that the use of PSI-guided HTO could provide enhanced accuracy in achieving the target MPTA and improve the prevention of PTS changes.