Introduction. The goal of arthrodesis around the ankle or of triple (hind foot) arthrodesis is a painless, plantigrade, and stable foot. Stress fracture is a differential diagnosis for pain following an ankle/subtalar arthrodesis. Management of stress fractures following sound ankle/subtalar fusion is extremely difficult as the entire movement tends to occur at the fracture site, hence hampering healing. Methods and materials. 33 patients underwent ankle/subtalar arthrodesis at our institute from 2000-2008. The average age of the patients was 69 years and the male: female ratio was 2:1. The minimum follow-up was for one year. Although there were some variations in technique, all the arthrodesis were performed by removal of articular cartilage, bone grafting of any defects and rigid internal fixation. Results. 2/33 patients developed a stress fracture of the distal tibia following successful ankle/subtalar fusion. An angle of ankle/subtalar fusion showed an average of 0 degrees +/− 3 degrees in the sagital plane, except for the two cases that developed the stress fracture. The angles in these cases were 13 and 11 degrees. The stress fractures occurred proximal to the level of the previous arthrodesis internal fixation devices (arthrodesis nail/cancellous screws). Intramedullary and extramedullary devices were utilised to obtain union across the stress fracture sites, without success. Discussion. Equinus of more than 10 degrees following ankle/subtalar arthrodesis is a high risk factor for developing a stress fracture of the distal tibia following ankle/subtalar arthrodesis. Stress fracture following successful ankle/subtalar arthrodesis causes severe morbidity. They are extremely difficult to treat, hence are best avoided if possible

Background. Subtalar fusion is traditionally an open procedure with potentially significant complications but there is little published on arthroscopic subtalar arthrodesis. Methods. We present the first UK series of 33 arthroscopic subtalar fusions in 32 patients, with a variety of pathologies. Results. There were 14 males and 18 females operated on between March 2004 and February 2009. Patients with previous hindfoot fusions were excluded as were patients who underwent combined arthroscopic hindfoot fusions. All patients had surgery by the senior author and followed an identical post-operative management plan. No patients were lost to follow-up. Successful outcome was taken as clinical and radiological evidence of fusion. We report a 100% union rate with 75.8% [25/33] union by 12 weeks, 97% [32/33] by 16 weeks with a single outlier achieving fusion at 22 weeks. There were no wound breakdowns, deep infections, neuromas or thrombotic events. Two patients required removal of metalwork. One patient developed mild CRPS and a further patient became symptomatic from concomitant calaneo-cuboid and talo-navicular joint arthrosis. Discussion. Previous authors have reported variable complication rates and significant rates of delayed and non-unions following open subtalar fusion. This technique respects the soft tissue envelope and therefore is less traumatic to the hindfoot. Our early results suggest that isolated arthroscopic subtalar fusion is a safe and reliable technique, even in patients with deformity, with an excellent union rate and minimal complications