Eiichi Shiigi , Tsuneari Takahashi , Koji Yoshida , Masahiro Numa , Keiko Kamata , Katsushi Takeshita , Takashi Sakai
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引用次数: 0
Abstract
Purpose
This study investigated whether the preoperative coronal plane alignment of the knee (CPAK), categorized as type I or II, has an effect on postoperative tibial internal rotation (TIR) relative to the femur in patients who received a medial pivot-cruciate retaining (MP-CR) total knee arthroplasty (TKA).
Methods
We retrospectively analyzed 62 patients who underwent MP-CR TKA with the GMK Sphere implant (Medacta International, Switzerland) from January 2024 to May 2025. Based on their CPAK classification, patients were divided into two groups (type I or II). Intraoperative kinematic assessments were performed using augmented reality (AR) CT-guided navigation (NextAR, Medacta), evaluating the dynamic elongation of medial and lateral collateral ligaments during either kinematic (KA) or mechanical alignment (MA) procedures. The primary measure was TIR at 30°, 60°, 90°, and 120° of knee flexion.
Univariate analyses identified significant differences, which were further assessed using multi-way ANOVA to determine interactions with CPAK classification.
Results
Notable differences in TIR were found between CPAK types I and II at 60° (2.1° ± 4.8° vs. −2.0° ± 4.2°, p = 0.009), 90° (7.0° ± 4.3° vs. 2.1° ± 5.6°, p = 0.002), and 120° (13.1° ± 5.2° vs. 7.5° ± 4.9°, p = 0.002). Additionally, at 90°, sex and alignment method (KA vs. MA) showed significant interaction with CPAK classification (F = 6.4; p = 0.015), while the alignment method alone had no significant effect on TIR.
Conclusion
The CPAK classification prior to surgery affected TIR outcomes regardless of the alignment method used, as measured via AR-CT navigation.
期刊介绍:
Journal of Orthopaedics aims to be a leading journal in orthopaedics and contribute towards the improvement of quality of orthopedic health care. The journal publishes original research work and review articles related to different aspects of orthopaedics including Arthroplasty, Arthroscopy, Sports Medicine, Trauma, Spine and Spinal deformities, Pediatric orthopaedics, limb reconstruction procedures, hand surgery, and orthopaedic oncology. It also publishes articles on continuing education, health-related information, case reports and letters to the editor. It is requested to note that the journal has an international readership and all submissions should be aimed at specifying something about the setting in which the work was conducted. Authors must also provide any specific reasons for the research and also provide an elaborate description of the results.