SLR - December 2019 - Jaime A. Ahluwalia
Reference: Kurokawa H, Taniguchi A, Morita S, Takakura Y, Tanaka Y. Total Ankle Arthroplasty Incorporating Total Talar Prosthesis. Bone Joint J. 2019 Apr;101-B(4):443-446Scientific Literature Review
Reviewed By: Jaime A. Ahluwalia, DPM
Residency Program: Grant Medical Center – Columbus, OH
Podiatric Relevance: With nearly 6 percent of the population suffering quality of life issues caused by ankle arthritis, a promising solution is in demand. Traditionally, ankle arthrodesis was the gold standard, however today a surgical evolution towards total ankle arthroplasty (TAA) is underway. Foot and ankle surgeons are leaning in to offer patients what is now considered a reliably better option in treating refractory end stage ankle arthritis. Preservation of motion with reduced risk of migratory arthritis has made TAA a patient preferred procedure. However, common barriers to success are implant subsidence and aseptic loosening, which surgeons are attempting to overcome with an artificially customized talus. This comparative study reviews the outcomes of standard TAA vs “combined TAA” in which the tibial component (from TNK system) is paired with an artificial talus designed from alumina ceramic, individualized to each patient via computed tomographic modeling.
Methods: The institutional review board in Nara, Japan approved this study comprising a total of 22 patients with stage 3b or 4 ankle arthritis defined by Takakura. The study prospectively compared 12 patients who underwent standard TAA and 10 patients who underwent combined TAA. The standard group was matched demographically to parallel the combined TAA group. Pre and post-operative functional and clinical outcomes were then measured in each group using the Japanese Society for Surgery of the Foot (JSSF) ankle-hindfoot scale, Ankle Osteoarthritis Scale (AOS), and the Self-Administered Foot Evaluation Questionnaire (SAFE-Q).
Results: The postoperative JSSF scores improved in both groups however, it was significantly higher in the combined TAA group (p = 0.0034). There was no significant difference in the mean AOS scores within the pain and functional outcomes between the two groups. Although there were no significant differences between the postoperative SAFE-Q scores in both groups, all mean subscale scores were higher in the combined TAA group consisting of pain, physical functioning, social functioning, shoe-related, and general health scores.
Conclusions: This study showed combined TAA resulted in better outcomes than standard TAA when considering JSSF scores and is therefore a worthy consideration for patients who exhibit severe deformity of the talus and poor bone quality. This study is limited particularly by being a small sample size with a relatively short follow up period, with a mean follow up of 58 months for the combined TAA group and 64 months for the standard TAA group. Nonetheless, this study provides deeper insight on the intraoperative and post-operative aspects of total ankle prostheses and may demonstrate an improvement in patient outcomes by reducing common complications when performing total ankle replacements.