[Pathological fracture of the carpal scaphoid (intra-osseous synovial cyst). Clinical and therapeutic aspect. Case report].

The authors report a case of fracture of the carpal scaphoid through an intraosseous synovial cyst. Synovial cysts are not uncommon in the carpal region, and are usually discovered as an incidental radiological finding: they rarely present with wrist pain and only exceptionally as a fracture. In our knowledge, only one other case of intraosseous synovial cyst of the carpal scaphoid presenting as a fracture has been published. Surgical treatment of these benign tumors, in cases of fracture or painful symptoms, consists of curettage of the lesion followed by impaction grafting of cancellous bone combined with stabilization in the case of a fracture. The use of a vascularized bone graft pedicled on the volar carpal artery enables simultaneous treatment of both the cyst and the fracture. The prognosis is good and relapse is exceptional.