Association Between Dynamic Tibiotalar Motion and Patient-Reported Outcomes After Total Ankle Arthroplasty With a Total Talar Prosthesis
Hiroaki Kurokawa, Rea Ikeda, Shinichi Kosugi, Masataka Yamamoto, Sayaka Wakiyama, Norihiro Tsujimoto, Yoshiyuki Kamatani, Yinghao Li, Nan Mei, Takuma Miyamoto, Akira Taniguchi, Hiroshi Takemura, Yasuhito Tanaka, Yoshinori Takakura, Kenji KawamuraBackground:
Although numerous studies have investigated the influence of preoperative deformity and postoperative implant alignment on clinical outcomes after total ankle arthroplasty (TAA), the relationship between dynamic tibiotalar motion and patient-reported outcomes remains unclear. This pilot study investigated whether preoperative, postoperative, and longitudinal changes in computed tomography (CT)-based tibiotalar kinematics are associated with clinical outcomes after combined TAA.
Methods:
Thirteen ankles that underwent combined TAA for end-stage varus ankle osteoarthritis were retrospectively evaluated. CT was performed preoperatively and 3 months postoperatively with the ankle in active dorsiflexion and plantarflexion under nonweightbearing. Preoperative and postoperative tibial models were registered using a globally optimal iterative closest point algorithm, enabling direct comparison of tibiotalar kinematics within a common tibial coordinate system. Spearman rank correlation was used to assess associations among preoperative kinematics, postoperative kinematics, longitudinal changes, and 2-year postoperative Self-Administered Foot Evaluation Questionnaire (SAFE-Q) scores.
Results:
All SAFE-Q subscale scores improved significantly (
Conclusion:
CT-based tibiotalar kinematics at maximum active dorsiflexion and plantarflexion showed exploratory associations with postoperative patient-reported outcomes after combined TAA. Restoration of postoperative inversion alignment, physiological internal rotational motion, and plantarflexion-related dynamic motion were associated with superior clinical outcomes. Given the small sample size, these findings should be interpreted as hypothesis-generating and require confirmation in larger cohorts. CT-based tibiotalar kinematics assessment using a common tibial coordinate system may provide a basis for further investigation of the relationship between postoperative tibiotalar kinematics and patient-reported outcomes after combined TAA.
Level of Evidence:
Level III, retrospective cohort study.