Child Knee Problems

The American Academy of Orthopaedic Surgeons (AAOS) lists knee disorders, juvenile arthritis, limb length discrepancy and Osgood-Schlatter disease among the most common knee problems for children. Other diseases or injuries can be problematic as well. Some will improve on their own; others will require medical or even surgical intervention.

Anatomy

• The knee is the largest joint in the body. The femur (thigh bone) and the tibia (shin bone) meet to form a hinge joint, which is protected by the patella (kneecap). Cartilage cushions the knee, while ligaments help stabilize it.

Bowed Legs and Knock Knees

• The AAOS reports that having bowed legs (physiologic genu varum) is common among infants and toddlers, who typically "outgrow" the condition by three years of age. Bowed legs, however, can result from Blount's disease, a condition affecting toddlers, children and adolescents in which the upper part of the tibia grows abnormally. The bowing weakens the knees' exterior ligaments. If severe enough, doctors might recommend surgical intervention because the resulting stress on the knee can lead to arthritis.

  Knock-knees is a condition in which one or both knees turn inward, weakening and loosening the interior ligaments. According to Children's Hospital Boston, most cases of knock-knees are mild and a natural part of growth; they begin self-correction after a child reaches age four. More severe knock-knees may require medical intervention with a night brace and/or orthopedic shoes, and even surgery if those measures are ineffective.

Other Disorders and Diseases

• Ligamentous laxity (loose ligaments), affecting up to 15 percent of children, according to Children's Memorial Hospital of Chicago, can cause knee joints to move beyond a normal range of motion, resulting in dislocated knees, sprains and torn ligaments. Avoiding high-impact activities can minimize potential injuries.

  The causes of limb length discrepancy (LLD), in which the lengths of the upper or lower legs differ, can include a previous injury to the leg, an infection in the bone, bone disease, or arthritis in the leg. Knee pain can result from the stress of an uneven gait.

  Osgood-Schlatter disease, most common in adolescents, causes pain just below the knee; the pain increases with certain activities. While there is no treatment, children usually outgrow the condition in one to two years. They can limit pain in the meantime by wrapping the knee or using a knee pad during sports and related activities.

  A condition in which bone fragments form within the knee, osteochondritis dissecans, can cause severe knee pain, swelling, a locked knee or the knee to give way. It often requires surgery to repair.

  Patellar dislocation, more common in girls, causes the knee cap to dislocate, or slip out of place. Treatment includes immobilizing the knee followed by strengthening exercises.

Injuries

• Different types of sports injuries can cause knee problems in children and adolescents. Injured collateral ligaments typically cause pain, bruising and swelling. RICE---Rest, Ice, Compression and Elevation---are the recommended treatment. Anterior cruciate ligament (ACL), caused by an awkward twisting of the knee, requires medical evaluation and often surgery to correct it. Fractures in the bones around the knee can result from a direct impact. Medical evaluation---including x-rays---are necessary for proper diagnosis.

Warnings

• If a child's knee is red or swollen, or if his knee problems are interfering with his activities, parents should always seek medical guidance.