3D-Printed Total Talus Replacement After Free Vascularized Medial Femoral Condyle Osteocutaneous Flap for Avascular Necrosis of the Talus Leads to Poor Clinical Outcomes: A Case Series.

Introduction: Avascular necrosis (AVN) of the talus is 1 of the most difficult foot and ankle pathologies to diagnose and manage. The purpose of this study was to report on the functional outcomes of 3D-printed total talus replacement (TTR) in 2 patients with talar AVN who both underwent a failed revascularization.

Methods: This is a case series of 2 patients with TTR after a failed revascularization and a comparison group of 25 patients with primary TTR. Clinical and functional outcomes are used to compare both groups.

Results: Patient 1 had a postrevascularization Visual Analogue Scale (VAS) pain score of 9. Imaging showed failure of the medial femoral condyle to incorporate with talar fragmentation. Patient underwent TTR at 5 months postoperatively. At 2 years postoperatively, the patient underwent a cavovarus foot reconstruction; however, patient continued to suffer from ankle pain (VAS 6) and ultimately underwent below knee amputation at 3 years after the TTR. Patient 2 initially underwent a core decompression for a talar bone infarct followed by revascularization procedure at 6 months postoperatively due to persistent pain and bony infarcts. At 18 months postrevascularization, the patient had a VAS pain score of 9 and progression of the AVN. She underwent a TTR. At 1-year follow-up, the VAS pain score was 8. Both patients had an ankle plantarflexion of 30° at their last TTR follow-up. The comparison group consisted of 25 patients who underwent 3D-printed TTR with mean postoperative VAS score and ankle plantarflexion of 3.7° and 41.8°.

Conclusion: Patients 1 and 2 demonstrated reduced plantarflexion and ankle motion after TTR relative to the comparison group which improved in both physical assessments. The first patient needed a below knee amputation for persistent pain. Patient 2 showed less improvement in all the foot and ankle outcome scores as compared with the primary TTR group.

Level Of Evidence: Level V: Retrospective case series.