SLR - February 2023 - Samuel Straus, DPM
Title: The Long-Term Clinical Results of Total Talar Replacement at 10 years or More After SurgeryReference: Morita S, Taniguchi A, Miyamoto T, Kurokawa H, Takakura Y, Takakura Y, Tanaka Y. The Long-Term Clinical Results of Total Talar Replacement at 10 Years or More After Surgery. J Bone Joint Surg Am. 2022 May 4;104(9):790-795. doi: 10.2106/JBJS.21.00922. Epub 2022 Feb 21. PMID: 35188906.
Level of Evidence: Level IV
Scientific Literature Review
Review By: Samuel Straus, DPM
Residency Program: Carilion Clinic – Roanoke, VA
Podiatric Relevance: Talar AVN is a challenge for even the most skilled surgeon. While arthrodesis is the standard treatment in cases with advances osteonecrosis it becomes less predictable. Even with bone grafting, in late state osteonecrosis limb length discrepancy, prolonged post-operative therapy, and loss of hind foot ROM are common sequela. For late-stage osteonecrosis, total talar replacement has become a reasonable alternative. The purpose of this study was to investigate the clinical and radiographic results of patients treated with total talar prostheses made with alumina and ceramic at 10 years or greater.
Methods: This was a retrospective study which included 19 feet in 18 patients treated with a customized total talar prosthesis (Kyocera). All patients were normal or underweight. 4 patients had a history of tobacco use, 1 patient had a history of alcohol abuse, 4 patients had diabetes, and 1 patient had rheumatoid arthritis. All patients had been treated with offloading or analgesic drugs for 6 months before operative intervention. The procedure was performed via an anterior approach. The talus was sectioned into 2 cm portions within the coronal plane. The talus was then removed prior followed by implantation of the prosthesis. Congruency was obtained and extrusion of the implant was not seen during hindfoot or ankle range of motion. The site was then closed without repair of the capsule. Patients were then followed for 10 years. The Japanese Society for Surgery of the Foot Ankle-Hindfoot Scale and the ankle osteoarthritis scale was utilized to pre-operatively and post-operatively evaluate pain, function, debility, and alignment. Radiographically joints were assessed for signs of DJD and implant subsidence using weight-bearing radiographs. Additionally, ankle range of motion was assessed using a goniometer.
Results: AOS and JSSF scores revealed significant improvement in terms of function and pain. Function was noted to have the most improvement with descending down steps. Patients reported pain at its worst and pain when walking with shoes was noted to have the most improvement. Pre to post-operative osteophyte formation increased from 9 to 17 ankles, 1 to 2 subtalar joints, and 3 to 12 talonavicular joints. The mean height-to-length ratio was relatively unchanged from 0.301 to 0.297. No significant subsidence of the prosthesis was observed. Ankle dorsiflexion changed from 0° to 7° and plantarflexion changed from 25° to 45°. No significant complications were reported, and no patients required revision.
Conclusion: In this study the Kyocera total talar implant yielded significant improvement in terms of function and pain despite radiographs signs of DJD at long term follow-up. Patients were also noted to have increased range of motion. Rheumatoid and diabetes did not have an impact on this study. There are concerns that weight could impact results of a total talar implants which was unable to be assessed in this study. A customized alumina ceramic implant is a useful treatment for late osteonecrosis and it yields favorable results.