Stress fractures are a relatively common overuse injury in runners and sportspeople. They can occur in a number of areas, including:
What Are They?
Stress fractures are microfractures that occur in bone as a result of repetitive load, rather than a one-off more substantial load that would cause other fractures. These loads can be either impact forces (for example the load through the bones of the leg that occur when running) or a pulling force exerted by a muscle/tendon or ligament.
When an area of bone is placed under repetitive stress it responds with increased activity in cells that strip away bone and in cells that regenerate bone. This leads to a weakening in the bone's internal framework. As this weakened area of bone is continually exposed to load it eventually leads to a small fracture occurring.
How Do You Diagnose Them?
Your physiotherapist will discuss with you your injury history, and this combined with their physical examination will give them a fair indication of the likelihood of a stress fracture compared with other overuse injuries.
A bone scan, CT scan or MRI may be performed to give a more clear picture and help in the diagnosis of a stress fracture.
How Do You Treat Them?
Rest from the aggravating activity is required to allow the bone to heal. Often a weightbearing cast (or "moon boot") may need to be worn as well. Most stress fractures will heal with six weeks of relative rest. Some gentle loading exercises performed during this period will generally aid in the fractures recovery and other rehabilitation to address any biomechanical issues that may have contributed to the injury should also be performed.