Silent surface osteosarcoma treated following the hemi-capanna technique. A case report

surface sarcomas are a rare entity that need correct diagnosis to differentiate parosteal (cPOS), periosteal and the high grade surface osteosarcomas (HGSO). HGSO has malignant behavior similarities with osteosarcomas and wide resection is the key to a successful treatment.1 The Capanna and Hemi-Capanna reconstruction techniques have being developed in order to avoid amputation after an oncological resection, allowing structural support from an allograft and biological advantages from a vascularised autograft.

46 years old male presenting with knee pain and 4 × 3 cm soft tissue tumor on the right tibial surface diagnosed of High Grade Surface Osteosarcoma (HGSO). Was treated by oncological resection followed by reconstruction with allograft and ipsilateral fibula autograft following the "Hemi-Capanna" technique and pedicled medial gastrocnemius flap.

sufficient evidence supports the use of the Capanna technique in major musculoskeletal reconstructions. The new "Hemi-Capanna" technique has less evidence but proves to be an easier surgical technique with good functional results and little complications.