The mid foot joints are usually the first to be affected in Charcot neuroarthropathy(CN). Reconstruction is technically demanding and fraught with complications. Fixation methods have evolved over time from cancellous screws, plates, bolts and a combination of these. We present our experience of mid foot fusion in CN from a tertiary diabetic foot centre. In this series we undertook mid foot corrective fusion in 27 feet (25patients) and are presenting the results of those with a minimumof six months follow up. Twelve of these had concurrent hindfoot fusion. Eleven patients had type 1 diabetes, 12 had type 2 and 2 were non-diabetics. 23 patients were ASA grade3 and 2 were ASA 2. 21 feet had ulcers preoperatively and mean HbA1c was 8.2. 13 patients had diabetic retinopathy and 6 had nephropathy. Average patient age was 59 (43 to 80) and our mean follow up was 35 months (7 to 67). One patient was lost to follow up and 2 patients died. 18 patients had plates, 3 had bolts and 6 had a combination. Complete follow up data was available for 26 feet in 24 patients. Satisfactory correction of deformity was achieved in all patients. The mean correction of calcaneal pitch was from 0.6 preoperatively to 10.6 degrees postoperatively, mean Meary angle from 22 to 9 degrees, talo- metatarsal angle on AP view from 33 to 13 degree. Bony union was achieved in 21 out of 26 feet and atleast one joint failed to fuse in 5. 19 out of 24 patients were able to mobilize fully or partially weight bearing. We had 6 patients with persisting and 3 withrecurrent ulceration. Seven repeat procedures were carried out which included 2 revision fixations. 4 out of 5 non-unions were seen where bolts were used alone or supplemented with plates. With our technique and a strict protocol 100% limb salvage and 81% union was achieved. 80% patients were mobile and ulcer healing was achieved in 72%. Corrective mid foot fusion is an effective procedure in these complex casesbut require the input of a multidisciplinary team for perioperative care

In foot and ankle surgery incorrect placement of implants, or inaccuracy in fracture reduction may remain undiscovered with the use of conventional C-arm fluoroscopy. These imperfections are often only recognized on postoperative computer tomography scans. The apparition of three dimensional (3D) mobile Imaging system has allowed to provide an intraoperative control of fracture reduction and implant placement. Three dimensional computer assisted surgery (CAS) has proven to improve accuracy in spine and pelvic surgery. We hypothesized that 3D-based CAS could improve accuracy in foot and ankle surgery. The purpose of our study was to evaluate the feasibility and utility of a multi-dimensional surgical imaging platform with intra-operative three dimensional imaging and/or CAS in a broad array of foot and ankle traumatic and orthopaedic surgery. Cohort study of patients where the 3D mobile imaging system was used for intraoperative 3D imaging or 3D-based CAS in foot and ankle surgery. The imaging system used was the O-arm Surgical Imaging System and the navigation system was the Medtronic's StealthStation. Surgical procedures were performed according to standard protocols. In case of fractures, image acquisition was performed after reduction of the fracture. In cases of 3D-based CAS, image acquisition was performed at the surgical step before implants placement. At the end of the operations, an intraoperative 3D scan was made. We used the O-arm Surgical Imaging system in 11 patients: intraoperative 3D scans were performed in 3 cases of percutaneus fixation of distal tibio-fibular syndesmotic disruptions; in 2 of the cases, revision of reduction and/or implant placement were needed after the intraoperative 3D scan. Three dimensional CAS was used in 10 cases: 2 open reduction and internal fixation (ORIF) of the calcaneum, 1 subtalar fusion, 2 ankle arthrodesis, 1 retrograde drilling of an osteochondral lesion of the talus, 1 Charcot diabetic reconstruction foot and 1 intramedullary screw fixation of a fifth metatarsal fracture. The guidance was used essentially for screw placement, except in the retrograde drilling of an osteochondral lesion where the guidance was used to navigate the drill tool. Intraoperative 3D imaging showed a good accuracy in implant placement with no need to revision of implants. We report a preliminary case series with use of the O-arm Surgical Imaging System in the field of foot and ankle surgery. This system has been used either as intraoperative 3D imaging control or for 3D-based CAS. In our series, the 3D computer assisted navigation has been very useful in the placement of implants and has shown that guidance of implants is feasible in foot and ankle surgery. Intraoperative 3D imaging could confirm the accuracy of the system as no revisions were needed. Using the O-arm as intraoperative 3D imaging was also beneficial because it allowed todemonstrate intraoperative malreduction or malposition of implants (which were repositioned immediately). Intraoperative 3D imaging system showed very promising preliminary results in foot and ankle surgery. There is no doubt that intraoperative use of 3D imaging will become a standard of care. The exact indications need however to be defined with further studies