Congenital knee dislocation

Congenital knee dislocation (CKD) is a rare condition that is present at birth, in which the knee joint is dislocated or not properly aligned. This condition is also known as congenital dislocation of the knee (CDK) or congenital knee dysplasia.

Etiology

The exact cause of CKD is unknown, but it is believed to be due to a combination of genetic and environmental factors. Some studies suggest that it may be associated with certain genetic disorders such as Down syndrome and Ehlers-Danlos syndrome. It may also be related to maternal use of certain medications during pregnancy, or to abnormal fetal positioning in the womb.

Symptoms

The most obvious symptom of CKD is a knee that is visibly out of place. The knee may be bent backwards (a condition known as genu recurvatum), or it may be bent forwards. Other symptoms may include limited range of motion in the knee, pain, and difficulty walking or moving the leg.

Diagnosis

Diagnosis of CKD is usually made at birth, based on physical examination of the knee. Imaging tests such as X-rays, ultrasound, and magnetic resonance imaging (MRI) may be used to confirm the diagnosis and to assess the severity of the dislocation.

Treatment

Treatment for CKD depends on the severity of the dislocation and the age of the patient. In mild cases, the knee may be manually repositioned and then immobilized with a cast or brace. In more severe cases, surgery may be required to realign the knee joint. Physical therapy is often recommended to improve range of motion and strengthen the muscles around the knee.

Prognosis

With early diagnosis and appropriate treatment, most individuals with CKD can achieve good functional outcomes. However, they may have an increased risk of developing osteoarthritis in the affected knee later in life.

See also

• Congenital dislocation of the hip
• Clubfoot
• Arthrogryposis