Heel pain – Pediatric (Sever’s Disease / Calcaneal Apophysitis)
There is a very painful condition that can potentially happen to physically active children between 8 and 14 years old (DOI: 10.7547/17-105).
This pain in the back/bottom of the heel can occur to one or both feet. There is no history of trauma. It seems that the pain just comes unexpectedly. Children with this relay that the more active they are, the worse the pain. When they are not very active, there is no pain. This tells us this has to be a mechanical issue within their feet.
Why does this happen?
The medical term is calcaneal (heel bone) apophysitis (inflammation of the growth plate).
Before any treatment is given, the cause of the pain has to be identified. Pain is a warning signal that something is wrong.
There is a growth plate on the back of the heel. This tissue is not as strong as bone and can become inflamed. That’s exactly what happens when a child has this condition.
To figure out why the growth gets inflamed, we need to know what structures are attached to the back of the heel bone.
The first, and most powerful, is the Achilles tendon. It attaches to the back and on the bottom of the heel bone. Second is the plantar fascia, a very strong ligament-like structure that supports the inner arch of the foot when standing, walking, or running.
Over-pronation of the foot is named as the leading cause of inflammation of the growth plate of the heel (DOI: 10.7547/1010133). But over-pronation is a very confusing disease that is not really understood. What does over-pronation, an excessive amount of weakness in the foot during standing, walking, and running, have to do with this inflammation of the growth plate?
If you don’t know what’s wrong, how can you fix it?
The image below is a 3D CT scan of the foot showing the back of the heel with ankle bone aligned on the heel bone compared to the partial dislocation of the ankle bone. Notice how the heel is vertically aligned with the lower leg bone when the ankle bone is aligned. When the ankle bone partially dislocates from the heel bone, the bottom of the heel bone turns outward.
Then we put the foot into motion to see how the heel abnormally shifts secondary to the ankle bone displacement.
The reason why the growth plate gets inflamed is the pulling and twisting of the bone on the back of the heel. When the child is walking or running, the Achilles tendon is pulling the bone in one direction and the arch tissue – the plantar fascia – is pulling in a different direction.
