ORIGINAL ARTICLES Plantar Pressures in Children With and Without Sever’s Disease Ricardo Becerro de Bengoa Vallejo, DPM, PhD* Marta Elena Losa Iglesias, PhD† David Rodrı ´guez Sanz, BS‡ Juan Carlos Prados Frutos, MD, PhD§ Paloma Salvadores Fuentes, PhD† Jose ´ Lo ´ pez Chicharro, MD, PhD* Background: A case-control study was conducted to compare static plantar pressures and distribution of body weight across the two lower limbs, as well as the prevalence of gastrocnemius soleus equinus, in children with and without calcaneal apophysitis (Sever’s disease). Methods: The participants were 54 boys enrolled in a soccer academy, of which eight were lost to follow-up. Twenty-two boys with unilateral Sever’s disease comprised the Sever’s disease group and 24 healthy boys constituted a control group. Plantar pressure data were collected using pedobarography, and gastrocnemius soleus equinus was assessed. Results: Peak pressure and percentage of body weight supported were significantly higher in the symptomatic feet of the Sever’s disease group than in the asymptomatic feet of the Sever’s disease group and the control group. Every child in the Sever’s disease group had bilateral gastrocnemius equinus, while nearly all children in the control group had no equinus. Conclusions: High plantar foot pressures are associated with Sever’s disease, although it is unclear whether they are a predisposing factor or a result of the condition. Gastrocnemius equinus may be a predisposing factor for Sever’s disease. Further research is needed to identify other factors involved in the disease and to better understand the factors that contribute to abnormal distribution of body weight in the lower limbs. (J Am Podiatr Med Assoc 101(1): 17-24, 2011) Apophysitis, or inflammation of an apophysis, is caused by microavulsions at the bone-cartilage junction 1 resulting from repetitive motion and overuse during periods of rapid growth. Calcaneal apophysitis was first described in 1912 by Sever 2 and later given the name ‘‘Sever’s disease.’’ The calcaneal apophysis is a cartilaginous growth center onto which the Achilles tendon inserts. 3, 4 Kvist and Heinonen 5 and Kim et al 6 refined the definition of Sever’s disease to indicate a traction epiphysitis. It is most commonly associated with sports that involve running and jumping. 7-9 In a retrospective study of 20 children with Sever’s disease, McKenzie et al 10 found that all of the children participated in such sports, mainly in track and field events and soccer. Sever’s disease has been reported to be the most common cause of heel pain in athletic children. 8, 11 Orava and Puranen 12 and Orava and Virtanen 13 found that it comprises 16.3% and 22.7% of exertion injuries in children, respectively. The heel pain limits physical activity and may interfere with *Escuela Universitaria Enfermeria, Fisioterapia y Podologia, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain. †Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Madrid, Spain. ‡Soccer Club Atle ´ tico de Madrid, Madrid, Spain. §Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain. Corresponding author: Ricardo Becerro de Bengoa Vallejo, DPM, PhD, Escuela Universitaria Enfermeria, Fisio- terapia y Podologia, Facultad de Medicina, Universidad Complutense de Madrid, Avenida Complutense s/n, Madrid, 28040 Spain. (E-mail: ribebeva@enf.ucm.es) Journal of the American Podiatric Medical Association  Vol 101  No 1  January/February 2011 17