Severs Disease

INTRODUCTION

Sever's disease or Calcaneal apophysitis is a condition that affects children between the ages of 10 and 13 years. It is characterized by pain in one or both heels with walking. During this phase of life, growth of the bone is taking place at a faster rate than the tendons. Hence there is a relative shortening of the heel-cord compared to the leg bones.

As a result, the tension the heel-cord applies to the heel bone at its insertion is very great. Moreover, the heel cord is attached to a portion of the calcaneus (heel bone) that is still immature, consisting of a mixture of bone and growing cartilage, called the calcaneal apophysis, which is prone to injury. Compounding to this is the fact that all these changes are happening in a very active child, prone to overuse. The end result is therefore an overuse syndrome of injury and inflammation at the heel where the heel cord (Achilles Tendonitis) inserts into the heel bone (Calcaneal apophysitis).

SYMPTOMS

The typical patient is a child between 10 and 13 years of age, complaining of pain in one or both heels with running and walking. The pain is localized to the point of the heel where the tendo-achilles inserts into the calcaneus (heel bone), and is tender to deep pressure at that site. Walking on his toes relieves the pain.

CAUSES

The actual pathology of the condition is one of more of an overuse syndrome in which the growth plate of the heel may become slightly displaced, causing pain. Biopsies of similar conditions have shown changes consistent with separation of the cartilage.

The cause of Sever's disease is not entirely clear. It is most likely due to overuse or repeated minor trauma that happens in a lot of sporting activities - the cartilage join between the two parts of the bone can not take all the shear stress of the activities. Some children seem to be just more prone to it for an unknown reason - combine this with sport, especially if its on a hard surface and the risk of getting it increases.

A pronated foot is one of the most common contributing factors. Over pronation is a biomechanical condition of the foot which involves a rolling outward of the foot at the ankle, so that when walking the inner side of the heel and foot bears more of the body's weight than is normal.

This causes a shortening or tightening of the achilles tendon and increases the force of its pull on the heel's growth plate thus causing severs disease. Orthotics such as the Dr Foot Pro are essential for children that over pronate.

Most cases of Sever's Disease show findings of equinus (tightness or loss of flexibility), of the calf muscle. Equinus is the single most important mechanical loading issue in Sever's Disease. Therefore it is imperative that we stretch the calf muscle.

The amount of equinus a child experiences can be determined by measuring the range of motion of the ankle with the knee flexed and extended.

When the knee is flexed, the amount of equinus of the calf muscle is measured. The podiatrist will extended the knee and measure both the soleus and gastrocnemius muscles (the two muscles that comprise the term calf muscle). Normal range of motion of the ankle in a normal gait (walking) cycle is 10 to 15 degrees beyond 90 degrees. This means that the normal range requires the ankle to dorsiflex (pushing the foot upwards) to 90 degrees plus an additional 10 to 15 degrees. An inability to complete this range of motion is termed equinus.

Other causes include a short achilles tendon which causes a pull of the achilles tendon on the heel's growth plate causing inflammation and pain.

If one leg is shorter than than the other the shorter leg tends to plantar flex more (push down) which pulls on the achilles tendon and can causes severs heel.

Flat or high arches can be a contributing factor. Both of these conditions causes the heel not to be positioned normally within the foot due to the height of the arch. Thus leads to the achilles tendon's attachment to the heel being affected. Abnormal arch height may contribute to the onset of Sever's Disease which is why orthotics as essential for children suffering with severs heel that have flat or high arches.

The condition is very similar to Osgood-Schlatter’s Disease which occurs at the knee.

WHAT YOU SHOULD DO

• Help an overweight child lose weight.
• Encourage your child to exercise moderately, avoiding extremes.

WHAT YOU SHOULD NOT DO

• Ignore the pain. You can not grow out of this disease!

TREATMENT

Treatment revolves around decreasing activity. Usual treatment has been putting children in a boot in slight equinus, or a cast with the foot in slight equinus, thereby decreasing the tension on the heel cord, which in turn pulls on the growth plate at the heel. As the pain resolves, children are allowed to go back to full activities.

• Complete resolution may be delayed until growth of the foot is complete (when the growth plate fuses to the rest of the bone of the heel).

• A soft cushioning heel raise is really important (this reduces the pull from the calf muscles on the growth plate and increases the shock absorption, so the growth plate is not knocked around as much).

• The use of an ice pack after activity for 20mins is often useful for calcaneal apophysitis - this should be repeated 2 to 3 times a day.

• As a pronated foot is common in children with this problem, a discussion regarding the use of long term foot orthotics may be important.

• If the symptoms are bad enough and are not responding to these measures, medication to help with inflammation may be needed. In some cases the lower limb may need to be put in a cast or fiberglass cast with a heel lift for 2-6 weeks to give it a good chance to heal.

• Calf stretches 6/day for 60 seconds each. Calf stretches are best accomplished by standing with the toes on the edge of a stretching block. Or you could use the pro stretch below.

LONG TERM IMPLICATIONS

This condition is self limiting - it will go away when the two parts of bony growth join together - this is natural. Unfortunately, Sever's disease can be very painful and limit sport activity of the child while waiting for it to go away, so treatment is often advised to help relieve it. In a few cases of Sever's disease, the treatment is not successful and these children will be restricted in their activity levels until the two growth areas join - usually around the age of 16 years. There are no known long term complications associated with Sever's disease.

Recommended Products

Orthotic shoe inserts are a good way to treat the symptoms, as well as help eliminate Severs Disease completely. Orthotic devices such as the Dr Foot Pro Insoles have had great clinical success in treating children who suffer from Severs Disease.

Click here to view orthotics

Most cases of Sever's Disease show findings of tightness of the calf muscle. The pro stretch enables the child to stretch not only the calf muscles but also the achilles tendon and the plantar fascia. Three 30-second step stretches work wonders for heel pain.

Click here to view the pro stretch

Podiatrists recommend the use of heel cushions for improved shock absorption and support and to limit the movement of the severe's heel. They will help to cushion and protect the heel each time your child takes a step. Also, because of the thickness of the heel cushion, the heel is slightly raised, which will help to reduce the pull of the Achilles Tendon on the tender and inflamed growth plate.

Click here to view the heel cushions