Birth defects, also called congenital anomalies, are physical abnormalities that occur before a baby is born. "Congenital" means "present at birth." (See also Introduction to Birth Defects of the Face, Bones, Joints, and Muscles Introduction to Birth Defects of the Face, Bones, Joints, and Muscles Birth defects, also called congenital anomalies, are physical abnormalities that occur before a baby is born. "Congenital" means "present at birth." Birth defects of the face and limbs are fairly... read more .)
Although rare, a dislocated knee in a newborn may be related to the position in the womb before birth. This birth defect can also occur in children who have Larsen syndrome, which consists of many dislocated joints (elbows, hips, and knees), clubfoot Clubfoot and Other Foot Defects Clubfoot (talipes equinovarus) is a birth defect in which the foot and ankle are twisted out of shape or position. Birth defects, also called congenital anomalies, are physical abnormalities... read more 
, and characteristic facial features (such as a prominent forehead, sunken nose, and wide-spaced eyes). It can also occur in children who have arthrogryposis multiplex congenita Arthrogryposis Multiplex Congenita Arthrogryposis multiplex congenita refers to a group of rare disorders that develop in the womb and cause many joints to become "frozen" in position. Birth defects, also called congenital anomalies... read more 
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When the infant is examined, doctors find that the leg cannot be bent more than a few degrees. Doctors also may do imaging tests, such as x-rays, magnetic resonance imaging (MRI), or computed tomography (CT), of the affected areas.
Treatment of Dislocated Knee
Physical therapy and splinting
Immediate treatment with physical therapy Physical Therapy (PT) Physical therapy, a component of rehabilitation, involves exercising and manipulating the body with an emphasis on the back, upper arms, and legs. It can improve joint and muscle function, helping... read more (flexing the infant's leg every day) and splinting the leg in a bent position usually results in a functional knee. Treatment is more complex in infants who have Larsen syndrome, arthrogryposis multiplex congenita, or other problems.
