What is it?
An apophysis is the ossific nucleus of a growth plate which is the site of insertion of ligaments and tendons. In the foot, the posterior aspect of the calcaneum is the site of insertion of the Achilles tendon superiorly and the plantar fascia inferiorly. The pull of these two structures can put a significant strain on the apophysis, leading to pain and inflammation over the heel bone itself.
What are the risk factors?
Rapid growth associated with the adolescent growth spurt, typically 8 – 12 years in girls or 10 – 14 years in boys. Regular high impact sports such as repetitive running, jumping, football and gymnastics.
What are the clinical features?
Sever’s disease is painful over the calcaneal tuberosity at the insertion of the Achilles tendon. It is usually unilateral but can be bilateral in some cases although never symmetrical. The pain is made worse by sporting or high impact activities and can commonly cause pain after prolonged walking. Flat shoes tend to exacerbate the pain. It is focally sore to palpation over the posterior heel and sometimes can swell in this area.
How should this condition be investigated?
History and examination are sufficient to form a clinical diagnosis. X-rays are not diagnostic and only required if alternative diagnoses are being considered.
What else could it be, and what are the alarming symptoms?
- Bone tumours or infection:progressive constant pain,night pain, rest pain, systemic features, pain at other sites
- Juvenile idiopathic arthritis:joint swelling and erythema, lymphadenopathy, hepatosplenomegaly
- Trauma, Achilles tendonitis, plantar fascitis
- Vitamin D deficiency
- Achilles tendon rupture:palpable gap, absent plantarflexion on calf squeeze
- Tight gastrocnemius and plantar fascia
- Vitamin D deficiency
- High levels of heavy impact sports
- Pain relief, ice packs and gel heel pads to reduce rubbing
- Stretch out tight muscles to reduce pressure on growth plate and stretch thoroughly prior to sport.
- Check vitamin D level and treat to bring level over 50nmol/L
- Reassurance – will get better as growth slows over 12-24 months
Once exacerbating features have been removed then activity modification is required. When the apophysis is inflamed in Sever’s disease it can take anything up to a few years for this to settle. Many activities such as swimming will not irritate it, whereas impact sports commonly do. Symptoms need to be managed until the process resolves. It is perfectly acceptable for children to manage the pain with anti-inflammatories whilst continuing sport if they wish.