Tibiotalocalcaneal arthrodesis is indicated for pain relief in patients with combined arthritis of the ankle and subtalar joint. An arthroscopic posterior approach was designed to improve upon traditional methods by using a minimally invasive technique. The technique involves prone positioning of the patient, one anterolateral and two posterolateral portals, and arthroscopic debridement of both the tibiotalar and posterior talocalcaneal joint. Stabilisation is obtained with a retrograde intramedullary nail, with static interlocking. This article presents illustrative cases and discusses some of the technical advantages and disadvantages over conventional open surgery. For surgeons familiar with posterior ankle or subtalar arthroscopy, this minimally invasive debridement and nailing appears to offer superior exposure, high patient satisfaction and lower postoperative morbidity than traditional methods; fusion is encouraged by preserving the medullary reaming material at the site of the fusion.