title: Osteosarcoma of navicular bone. En bloc excision and salvage of the foot.
abstract: OBJECTIVE
  To present foot salvage for osteosarcoma of the navicular bone with en bloc resection and reconstruction using bone allograft and talus-cuneiform arthrodesis. PATIENT AND SURGICAL TECHNIQUE: A 20 year-old male with a history of osteosarcoma of the distal femur presented to our department 5 years later with a metastatic lesion of the navicular bone of the contralateral foot. The patient received 4 cycles of neo-adjuvant chemotherapy with satisfactory response. Tumor shrinkage allowed en bloc excision of the navicular bone with clear margins. Reconstruction was done using a tricortical allograft and talus-allograft-cuneiform arthrodesis, secured with a mini-fracture plate (Synthes). Weight bearing protection was advised for 2 months and partial weight bearing for another 4 months. Patient received 4 cycles of adjuvant chemotherapy.
  
  
  RESULTS
  Three years postoperatively, the patient was free of local recurrence or distant metastasis. There were no signs of allograft resorption, fracture or non union. The patient was asymptomatic and full weight bearing. Ankle and subtalar joint motion was within normal limits.
  
  
  CONCLUSIONS
  Foot salvage after excision of osteosarcoma of the navicular bone could be possible if en bloc resection of the lesion could be performed. Talus-cuneiform fusion with allograft interposition is a viable reconstructive option.
authors.affiliation: Orthopaedic Surgery, Biomechanics Lab, Mayo Clinic, Rochester, MN, USA. bsakellariou@gmail.com
authors.forename: Vasileios I
authors.initials: VI
authors.lastname: Sakellariou
authors.forename: Andreas F
authors.initials: AF
authors.lastname: Mavrogenis
authors.forename: George A
authors.initials: GA
authors.lastname: Mazis
authors.forename: Panayiotis J
authors.initials: PJ
authors.lastname: Papagelopoulos
mesh_terms: D001174:Arthrodesis; D001859:Bone Neoplasms / Q000473:pathology / Q000601:surgery*; D016025:Bone Transplantation; D005269:Femur; D006801:Humans; D008297:Male; D012516:Osteosarcoma / Q000556:secondary / Q000601:surgery*; D013639:Tarsal Bones / Q000601:surgery*; D055815:Young Adult