Genu recurvatum is a deformity in the knee joint, so that the knee bends backwards. In this deformity, excessive extension occurs in the tibiofemoral joint. Genu recurvatum is also called knee hyperextension and back knee. This deformity is more common in women and people with familial ligamentous laxity. Hyperextension of the knee may be mild, moderate or severe. The normal range of motion (ROM) of the knee joint is from 0 to 135 degrees in an adult. Full knee extension should be no more than 10 degrees. In genu recurvatum, normal extension is increased. The development of genu recurvatum may lead to knee pain and knee osteoarthritis.

Causes

The following factors may be involved in causing this deformity:

Pathophysiology

The most important factors of knee stability include:

Treatment

Treatment generally includes the following:

Incidence

This condition is considered to be rare, with about 1 in 100,000 births being affected by the congenital form of genu recurvatum, although it's a common feature in some disorders, such as in joint hypermobility, which affects 1 in 30 people.