Tibia vara caused by focal fibrocartilaginous dysplasia. Three case reports

Abstract

We present three cases of a previously undescribed condition characterised by unilateral tibia vara associated with an area of focal fibrocartilaginous dysplasia in the medial aspect of the proximal tibia. The three children affected were aged 9, 15 and 27 months respectively. Two required tibial osteotomy, but in one the deformity resolved without treatment. The pathogenesis of the focal lesion remains conjectural; the most likely explanation is that the mesenchymal anlage of the tibial metaphysis has, for unknown reasons, developed abnormally at the insertion of the pes anserinus.

Tibia vara in focal fibrocartilaginous dysplasia

“…The finding was identical to that described by Bell et al (1985), with dense hypocellular tissue resembling fibrocartilage in some areas and tendon in others. Scintimetry showed a high uptake focally within the proximal medial part of the right tibia at the junction of the metaphysis and the diaphysis.…”

“…The 14 cases of FFD reported (Bell et al 1985, Bradish et al 1988, Husien and Kale 1989, Olney et al 1990, this report) show identical clinical, radiographic and histological features that have been recognized only recently. There are 7 boys and 7 girls.…”

“…Bell et al (1985) suggest that the mesenchymal anlage of the tibial metaphysis has, for unknown reasons, developed abnormally at the insertion of the pes anserinus. Langenskiold (personal communication) recognized a similarity between the lesion and his findings in rabbits when localised damage to the growth plates was provoked with X-rays (Langenskiold and Edgren 1949).…”

Focal Fibrocartilaginous Dysplasia in Distal Radius

“…To the best of our knowledge, the reported cases of FFCD in the upper extremity were in diaphyseal area of long bones mostly in ulna, which can result in angulation and radial head dislocation (1,8). In our cases with FFCD of distal radius, the clinical appearance of the involved wrists were very similar to radial club hand.…”

Abnormal alignment of the left lower extremity and irregular gait

“…Focal fibrocartilaginous dysplasia (FFCD) is a rare benign entity first described by Bell in 1985 [1]. The most common site of FFCD is the proximal tibia followed by distal femur, forearm, humerus, phalanx, and vertebra transverse process [2,3].…”