Focal fibrocartilaginous dysplasia (FFCD) in the proximal femur causing coxa vara: A unique case report and review of the literature

摘要

BACKGROUND: Focal fibrocartilaginous dysplasia (FFCD) is an uncommon developmental defect of bone, where cortical bone is replaced by fibrous tissue. The condition has most commonly been reported in the upper tibia causing tibia vara. Several other sites have also been described including the distal femur, ulna, humerus, radius and phalanx. METHODS: We report a unique case of FFCD of the upper medial femur that caused coxa vara. The diagnosis was suspected on X-ray and confirmed on MRI and histology. Treatment included valgus subtrochanteric proximal femoral osteotomy, intralesional biopsy and curettage of the lesion. A literature review using PubMed/Medline and Google Scholar was completed to identify previous publications on FFCD up to February 2015. RESULTS: This is the first report of FFCD associated with coxa vara in the proximal femur. Eighteen cases of FFCD in the distal femur have previously been reported. The disorder is most commonly reported in the proximal tibia. CONCLUSION: FFCD should be considered in the differential diagnosis of a cortically based lytic lesion associated with bony deformity in growing bone. Further research is needed to define the aetiopathogenesis and natural history of the disorder. Treatment guidelines are needed for atypical locations. Level of evidence: Level V (case report).