Early Outcomes of Combined Total Ankle Total Talus Replacement Using a 3D-Printed Talus Component with Hindfoot Arthrodesis

SLR - December 2022 - Garrett D. Nelson, DPM

Title - Early Outcomes of Combined Total Ankle Total Talus Replacement Using a 3D-Printed Talus Component with Hindfoot Arthrodesis

Reference - Madi NS, Fletcher AN, Pereira GF, Balu A, DeOrio JK, Parekh SG. Early Outcomes of Combined Total Ankle Total Talus Replacement Using a 3D-Printed Talus Component With Hindfoot Arthrodesis. Foot & Ankle Specialist. 2022;0(0).

Level of Evidence - Therapeutic Level IV

Scientific Literature Review
Reviewed By- Garrett D. Nelson, DPM
Residency Program - Regions Hospital/HealthPartners Institute – St. Paul, MN

Podiatric Relevance - The talus is notorious for its tenuous blood supply and tendency for avascular necrosis. There are different stages of this disease, and multiple different treatment options including non-operative management. However, difficulty lies with concomitant talar pathology such as arthritis. Options at this point become much more limited, but with advancing technology, a three-dimensional printed total talus replacement has a promising outlook. This study sought to evaluate the clinical outcomes, radiographic outcomes, and union rate in combined total ankle and total talus replacement (TATTR) with hindfoot arthrodesis. 

Methods - Retrospective review of 9 patients who underwent TATTR with a hindfoot arthrodesis from 2016 – 2020. Patients were included if they had TATTR or TTR with adjacent arthrodesis. Patients were excluded if they had followed up less than 11 months, active infection, Charcot, or osteonecrosis. Patient’s charts were reviewed to collect demographics, preoperative and postoperative VAS pain scores, as well as union rates, complications and need for revision surgery. Preoperative and postoperative radiographs were evaluated for specific parameters including tibiotalar alignment, talar tilt angles, talar declination and talocalcaneal height.  All talus implants utilized by the surgeons were custom 3D printed composed of cobalt chrome alloy. Sizes of the implant were based on CT scanning of the contralateral talus. In patients with known arthritis, whether in the subtalar joint or talonavicular joint, the 3D implant was prepared in a way to allow bone ingrowth to achieve fusion. The TAR system was chosen based on the surgeon’s discretion. 

Results – The mean follow up of the 9 patients included in this study was 19.4 months. Seven of the patients underwent TATTR and subtalar joint arthrodesis, 2 of which underwent concomitant talonavicular arthrodesis. Two patients underwent TTR with subtalar joint arthrodesis. Significant improvement in VAS scores noted. All patients achieved successful union of the subtalar joint and talonavicular joint. Significant improvements noted in talocalcaneal height and tibiotalar alignment radiographically. One patient underwent revision surgery for persistent varus ankle deformity requiring fibular and tibial osteotomies. No cases of explant revision surgery, below knee amputations or postoperative infections. 

Conclusions - The short-term outcomes reported in this study demonstrated significant improvement in pain scores and ankle range of motion in patients who underwent combined TATTR and hindfoot arthrodesis. In addition, there were no short-term failures and all patients reached complete healing of the hindfoot arthrodesis sites. Although the sample size is small, this study evaluated a novel treatment approach that will benefit the current body of literature. This is the first study to evaluate the clinic as well as the radiographic outcomes of the combined procedures. The early results of this study suggest that the combination of procedures provides a viable surgical option for patients with end stage arthrosis of multiple joints. Although long term outcomes of this procedure combination are needed, the improvement of VAS pain score, improvement of multiple radiographic parameters and 100% hindfoot union rate give promise to this patient population.