Severs Disease

Sever's disease, also known as calcaneal apophysitis, is an inflammatory condition of the growth plate of the heel (calcaneus). Sever's disease is seen during periods of active bone growth, particularly between the ages of 10 and 14 years old. Sever's disease is a self limiting condition, meaning that all cases of Sever's disease will disappear once bone growth is finalized and the growth plate of the heel closes. Skeletal maturity and closure of the growth plate occurs for most boys at about 15-16 years of age.

Sever's disease is much more common in boys than in girls. Most cases of Sever's disease are found in children who are moderately obese. Sever's disease can also occur in very active children. Sever's disease is common in periods when activities for these children increase such as twice daily football practices in the fall or at the onset of track season in the spring.

Treatment of Sever's Disease

The treatment of Sever's disease depends upon the severity of symptoms experienced by the patient. Most children can continue with activities, including sports and begin a simple program of stretching and heel elevation that will make a significant difference in heel pain due to Sever's disease. If stretches and heel elevation is unsuccessful in controlling the symptoms of Sever's disease, children should be removed from sports and placed on restricted activities.

• Mild Symptoms - Wear a 3/8 heel lift at all times (not just during physical activity). It is important to use a firm lift and not a soft heel pad. 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.

• Moderate Symptoms - Follow the directions for minor symptoms and decrease activity including elimination of any athletic activity. In addition to stretching by day, a night stretching splint can be worn while sleeping.  Use of an AirHeel during the day is helpful.

• Severe Symptoms - Follow the directions for mild and moderate symptoms. Children should be removed from sports activities such as football, basketball, soccer or gym class. A below knee walking cast with a heel lift or in severe cases, non-weight bearing fiberglass cast, may be indicated for 4-6 weeks. The cast should be applied in a mildly plantar flexed position. Cam Walkers should not be used for Sever's Disease unless they have a built in heel lift.

Apophysis - secondary growth plate.

Calcaneus - the heel bone.

Equinus - tightness in the calf and Achilles tendon limiting normal range of motion of the ankle.

Itis - is a suffix derived from both Latin and Greek that refers to inflammation.

In the growing child, there are a number of different ways that bones grow. In the calcaneus (heel bone), growth comes from two separate growth plates. The lesser of the two growth plates is called the apophysis. The apophysis of the calcaneus is located between the back and the bottom of the heel at that spot that hits the ground each time we take a step. The Achilles tendon, which is the most powerful tendons in our body, attaches to the proximal aspect of the apophysis. The plantar fascia attaches to the distal aspect of the apophysis. Both the Achilles tendon and plantar fascia place traction, or pulling on the growth plate and contribute to inflammation of the secondary growth plate called apophysitis.

The calcaneal apophysis is very apparent on x-ray and continues to grow until approximately age 12 in girls and age 15 in boys.

The calcaneus is very firm on the outside (cortical bone) and very soft and spongy on the inside (cancellous bone). Load is applied to the calcaneus in two ways. First, direct load is applied to the calcaneus with each step that we take.  This load is equal to or greater than the mass of our body. Second, traction load is applied to the calcaneus by the structures that are attached to it that pull against the bone. Proximally, the Achilles tendon pulls on the calcaneus.  And distally, muscle and fascia resist the load applied to the calcaneus by the Achilles tendon.

The calcaneal apophysis is unique in that it is affected by both of these types load bearing. The apophysis must accommodate the pull of the Achilles tendon on the posterior heel and the resistance of the plantar fascia on the bottom of the heel. In addition to the plantar fascia, several other soft tissue structures pull on the plantar aspect of the heel including muscle and ligaments. The pull of each of these soft tissue structures works much like a lever arm and results in mechanical load being applied to the calcaneal apophysis. For additional information on how the leg and foot perform as a lever arm, please refer to our pages on CT Band Syndrome.

Interestingly, Sever's disease is found in young boys who overload the apophysis with both body weight and mechanical load. Most cases of Sever's disease are found in young boys (8-12 y/o) who are overweight and have recently started a new physical activity.  This combined load of body mass and increased mechanical load results in an inability of the growth plate to function normally.  The heel pain experienced by children with Sever's disease is an inflammatory response of the growth plate to this increased load.

Most cases of Sever's disease show findings of equinus, or tightness of the calf muscle. How do you measure equinus? Equinus 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 soleus muscle is measured. With the knee extended, both the soleus and gastrocnemius muscles are measured. Imaginary lines are established on the long axis of the leg and the foot. By dorsiflexing the foot (toward the body) an angular measurement is established between these two lines. Normal range of motion of the ankle, to complete a normal gait cycle, is 10 to 15 degrees beyond 90 degrees. This means that the normal range requires the ankle to dorsiflex to 90 degrees plus an additional 10 to 15 degrees. An inability to complete this range of motion is termed equinus.

In summary, the biomechanical forces that contribute to Sever's disease include both traction applied to the bone and the load applied to the heel at the heel strike phase of the gait cycle. The pain experienced by children with Sever's disease is simply due to a growth plate that cannot keep up with the demands applied to it.

The symptoms of Sever's disease include pain that tends to increase with activity. Pain is present at the onset of activity and continues to increase with prolonged activity. Pain is in the body of the calcaneus. Direct pressure, side to side on the medial and lateral walls of the heel is most common location of pain. Swelling and redness are uncommon in cases of Sever's disease.

Baxter's nerve entrapment - entrapment of the 1st branch of the lateral plantar nerve of the posterior tibial nerve.

Juvenile rheumatoid arthritis (JRA).

Retrocalcaneal bursitis (Albert's Disease) - this is the formation and inflammation of a bursa at the back of the heel between the heel bone and Achilles tendon.

Rheumatic Fever.

Septic Arthritis.

Sero-negative arthropathies such as Reiter's Syndrome.

Stress fracture of the calcaneus.

Tarsal Tunnel Syndrome.

• Heel Pain

• Plantar Fasciitis

• Calcaneal Fractures

• CT Band Syndrome

• Arch Pain

This article was written by Jeffrey A. Oster, DPM and last updated 2/8/13.  No additional information is available for this topic.