Optimal treatment for symptomatic talus Osteochondral Lesions (OCLs) where primary surgical techniques have failed has not been established. Recent advances have focussed on biological repair such as Autologous Chondrocyte Implantation (ACI) however funding for this treatment is limited. Stem cell therapy in the ankle has not been assessed. The purpose of this pilot study was to evaluate the safety and efficacy of stem cell therapy in the treatment of ankle OCLs. The study was approved by the new procedures committee. Between January 2015 and December 2016, 26 patients, mean age of 36 years (range 16–58 years) with persisting disabling symptoms underwent Complete Cartilage Regeneration (CCR) using stem cells for failed primary treatment for ankle OCLs. Treatment involved iliac crest bone marrow aspiration, centrifugation to obtain bone marrow concentrate (BMC), and then injection of the BMC combined with hyaluronic acid into the OCL. Any necessary additional procedures, e.g. bone grafting or lateral ligament reconstruction were also undertaken. In 18 patients the lesion was on the medial talar dome, in 5 the lateral talar dome, 2 multiple, 1 tibial plafond. The