ANKLE PAIN IN CHILDREN
By: Robert H. Sheinberg, D.P.M., D.A.B.F.A.S., F.A.C.F.A.S.
The ankle joint is a complex structure composed of three bones, eleven ligaments, growth plates and cartilage that allow the ankle joint to move smoothly. Tendons move the foot in all directions across the ankle joint. Injuries to the ankle can affect any of these structures. Ankle pain in children is most commonly due to traumatic injuries. This can come from twisting the ankle during a sport or activity or from blunt trauma to the area.
1. FLAT FEET: A primary source of ankle pain, especially in active children. Pain is most common on the inner aspect of the lower leg, ankle and foot. The condition is usually associated with premature fatigue and general avoidance of most activities that require running. If associated with tightness of the calf muscle, this can be a very harmful combination that can preclude most activities for these children and cause chronic low-grade pain for many years. Occasionally, immobilization of the leg in a cast to stretch the tight muscles followed by orthotics and physical therapy are indispensable in not only eliminating the problem but allowing the child to participate in most activities at a much higher level than ever before.
2. GROWTH PLATES: Growth plates are present on the inner and outer aspect of the ankle bone. They are areas within the bone that allow bone growth. It is the weak link in the ankle when comparing it to the ligaments and bone structure. Injuries are most common in sports, especially soccer. Injuries usually cause a significant amount of pain, swelling and difficulty weightbearing. Examination usually reveals pinpoint tenderness on the growth plate itself. The treatment of these injuries is usually dictated by the injury type. Simpler injuries may be immobilized for a period of 4-8 weeks. More moderate to severe injuries may require surgery to put the growth plates back into their normal position. Long-term prognosis is excellent for simple injuries and guarded for more complex ones.
3. FRACTURES: Breaks of the bone can also occur in the lower leg and in the ankle bone itself. They are usually accompanied by growth plate injuries. These injuries usually occur from twisting the ankle or foot (i.e. basketball or soccer). Swelling that is diffuse, discoloration and pain with any attempts at weightbearing are observed. Treatment for simple breaks may require cast immobilization for a period of 4-8 weeks. If the bones are out of place they may be gently manipulated back into position nonsurgically. If grossly malaligned, surgery may be necessary to restore normal anatomy. Prognosis is dependent on the bone injured with the type and the timing of treatment.
4. LIGAMENT INJURIES: Usually less common in children and more common in teenagers. They occur when the ligament is twisted beyond its elastic limits. This can cause a ligament to stretch, partially or completely tear. There is usually pinpoint tenderness over the ligament(s) involved. Significant swelling would be present in the front of the ankle and discoloration can extend along the outside of the foot, even down to the toes. Weightbearing is always difficult. Treatment of this condition is always to immobilize the ankle for a period of 4-6 weeks and follow with a short course of physical therapy. Prognosis is excellent in almost every case.
5. CARTILAGE INJURIES: Injuries to the cartilage (osteochondral lesions or osteochondritis desiccants) are uncommon but when they do occur they occur on the talus. When caused by trauma they are generally on the outside of the talus. When injury occurs on the inside of the bone the cause is usually more unclear. It may be caused by trauma but other possibilities include disturbance in the circulation to the bone or endocrine abnormalities.
Patients will usually complain of persistent soreness in the ankle joint with activity. Plain x-rays may show the lesion. However, MRIs and occasionally CT scans are necessary to fully clarify the extent of the injury and formulate a treatment plan. Children and adolescents with these injuries usually show signs of spontaneous healing but the ankle may need to be immobilized in a nonweightbearing cast for 6-12 weeks to allow healing and prevent long-term problems. If the pain persists arthroscopy may be necessary to treat the condition. The long-term prognosis may be excellent if the defect in the bone and cartilage is very small.
6. MISCELLANEOUS: Other conditions may cause ankle pain in children that are not traumatically induced. Inflammatory conditions such as juvenile rheumatoid arthritis need to be ruled out, especially if a child has not been injured and has chronic ankle pain. Rarely infections and tumors are the cause of the problem. If present though, they must be diagnosed and treated immediately.
Injuries to any one of these areas can cause long-term problems if not treated early and effectively. X-rays are necessary to evaluate the bone structure and properly treat the area. In children or teenagers it is important to immobilize the ankle to give it proper rest. This will allow the ligaments, bones and growth plates to heal properly. In some cases the bones may be grossly displaced. CT scans may be necessary to evaluate the injury further. In rare cases surgery is necessary to reposition the bones and growth plate to allow it to heal properly. Ligament injuries that are not treated immediately can cause chronic instability. After the injury apparently heals the ligaments will be loose and the ankle will twist very easily, causing recurrent problems. Following immobilization physical therapy may be necessary to aid in the rehabilitation of the injury and allow complete recovery.