What is Server's Disease?
Posterior heel pain is a common condition for active children aged between 8 to 14 years who have no history of injury. Such pain accounts for between 2% and 16% of musculoskeletal injuries in children in this age group.
A common cause of posterior heel pain in this age group is Sever’s disease, which typically occurs in children who have recently gone through growth spurts or during periods of high activity. Patients will generally be found to have limited ankle joint dorsiﬂexion, an underlying bio-mechanical deformity of variable nature, and worse pain with increased activity.
Sever’s disease was first described by James Warren Sever in 1912. He described it as a painful inflammation of the calcaneal apophysis associated with muscle strain in the immature paediatric skeleton that results in posterior heel pain, swelling and walking difficulties. The condition is thought to be caused by recurring micro trauma due to the traction of the Achilles tendon on the secondary growth plate of the calcaneus.
In diagnosing Sever’s disease, compression of the medial and lateral aspects of the heel will usually reveal tenderness, but no erythema, swelling, dermatologic abnormalities or other local pathology. A positive squeeze test in a child or adolescent with heel pain but no other signs and symptoms almost always indicates a diagnosis of Sever’s disease.
How Server's Disease Causes Pain
Children with Sever’s disease usually report non-radiating pain and tenderness in the heel or around the Achilles tendon of one foot or, sometimes, both feet. The pain will tend to occur during physical activity and symptomatic children will often limp following activity to avoid pressure through the affected heel. Pain may also be associated with a reduction in Achilles tendon flexibility that results in loss of ankle dorsiflexion range of motion.
Multiple factors may contribute to the development of apophysitis. First, during a time of rapid growth, such as the pubertal growth spurt, bone growth exceeds the ability of the muscle-tendon unit to stretch sufficiently to maintain its previous level of flexibility, causing increased tension at the attachment site. In the young athlete, training and competition increase force generation of the attached muscle and amplify traction forces at the apophysis. Underlying biomechanical factors such as an abnormal foot or knee posture may exacerbate abnormal forces at the apophysis. The end result of these processes is inflammation and micro trauma of the apophysis.