Brothers with genu recurvatum.

Genu recurvatum deformity is rare, usually resulting from injury to the anterior part of the proximal tibial growth plate. However, a small group of cases have no known cause. We describe brothers with the same type of this deformity on the same side. The degree of deformity differed between them, but deformities began at the same age in both (17 years) and progressed over a short period. There was no history of trauma, or other orthopaedic or genetic disorders. These features strongly suggested involvement of heritable risk factors.