The calcaneal apophysis is a growth center where the Achilles tendon and the plantar fascia attach to the heel. It first appears in children aged 7 to 8 years. By ages 12 to 14 years the growth center matures and fuses to the heel bone. Injuries can occur from excessive tension on the Achilles tendon and the plantar fascia, or from direct impact on the heel. Excessive stress on this growth center can cause irritation of the heel, also called Sever?s disease.
There are several theories surrounding the cause of Sever?s disease. These range from a tight Achilles tendon, to micro stress fractures of the heel, to biomechanical mal-alignment, to trauma, to flat feet, and even to obesity. But the prevailing theory suggests the onset of Sever?s disease occurs when the child’s growth plate is at its weakest, while a tightened Achilles tendon pulls repeatedly on the growth plate, such as during AGS.
The typical clinical presentation is an active child (aged 9-10 years) who complains of pain at the posterior heel that is made worse by sports, especially those involving running or jumping. The onset is usually gradual. Often, the pain has been relieved somewhat with rest and consequently has been patiently monitored by the patient, parents, coaches, trainers, and family physicians, in the expectation that it will resolve. When the pain continues to interfere with sports performance and then with daily activities, further consultation is sought. It should be kept in mind that failure to instruct patients and parents that continual pain, significant swelling or redness, and fever are not signs of Sever disease and therefore require further evaluation could result in failure to diagnose a condition with much more serious long-term consequences.
The x-ray appearance usually shows the apophysis to be divided into multiple parts. Sometimes a series of small fragments is noted. Asymptomatic heels may also show x-ray findings of resporption, fragmentation and increased density. But they occur much less often in the normal foot. Pulling or ?traction? of the Achilles tendon on the unossified growth plate is a likely contributing factor to Sever?s disease. Excessive pronation and a tight Achilles and limited dorsiflexion may also contribute to the development of this condition.
Non Surgical Treatment
stretching exercises can help. It is important that your child performs exercises to stretch the hamstring and calf muscles, and the tendons on the back of the leg. The child should do these stretches 2 or 3 times a day. Each stretch should be held for about 20 seconds. Both legs should be stretched, even if the pain is only in 1 heel. Your child also needs to do exercises to strengthen the muscles on the front of the shin. To do this, your child should sit on the floor, keeping his or her hurt leg straight. One end of a bungee cord or piece of rubber tubing is hooked around a table leg. The other end is hitched around the child’s toes. The child then scoots back just far enough to stretch the cord. Next, the child slowly bends the foot toward his or her body. When the child cannot bend the foot any closer, he or she slowly points the foot in the opposite direction (toward the table). This exercise (15 repetitions of “foot curling”) should be done about 3 times. The child should do this exercise routine a few times daily.
Exercises that help to stretch the calf muscles and hamstrings are effective at treating Sever’s disease. An exercise known as foot curling, in which the foot is pointed away from the body, then curled toward the body in order to help stretch the muscles, has also proven to be very effective at treating Sever’s disease. The curling exercise should be done in sets of 10 or 20 repetitions, and repeated several times throughout the day.