Femur fibula ulna syndrome

Femur-fibula-ulna syndrome, or FFU syndrome, is a very rare, sporadically occurring condition marked by combined malformations of the femur, or thigh bone, the fibula, or calf bone, and the ulna, one of the forearm bones. It affects multiple limbs at once, with the upper limbs typically showing more severe abnormalities than the lower limbs, and malformations occurring more often on the right side than the left, with no predictable pattern from one case to the next. It was first identified by Lenz and Feldman in 1977, and there remains ongoing medical debate over whether it is truly distinct from proximal femoral focal deficiency or represents the same underlying condition.