Frequently Asked Questions
Bone Stress Injuries And Fractures
Stress fractures fall into the category of “bone stress injuries” which tend to occur when a bone is unable to handle the repetitive loads demanded of it. This results in localised pain over the area of bone affected. These injuries begin as a painful stress reaction that is not yet a full fracture. A stress fracture is a progression of this and is a small break in a bone, which if not treated, can progress to becoming a complete fracture.
Bone stress injuries are considered to be due to an imbalance between normal microdamage and bone remodelling. These injuries are seen in both elite level athletes and inactive people, with women sustaining 2-10 times more bony stress injuries than men. These injuries tend to be caused by:
- high training loads
- a sudden increase in physical activity or training
- biomechanical factors such as muscle strength, footwear and technique
- factors that increase risk due to impact on bone health or remodelling
- diet and nutrition with deficits in calcium and vitamin D increasing the risk, along with low calorie intake
- hormonal changes such as menstrual disturbance and menopause
- genetic factors
Both bone stress fractures and bone stress reactions cause localised pain over the affected bone with the pain gradually increasing over time. In the early stages pain may only be experienced with high impact activities such as jumping, running and even walking but as the condition progresses pain may be present even at rest.
Which foot bones are more commonly affected by bone stress injuries ?
- navicular (a small bone on the inside of the foot below the ankle)
- 5th metatarsal (connects to the 5th toe on the outside of the foot)
- 2nd metatarsal (connects to the second toe in the middle of the foot)
- Medial malleolus (the bony knob on the inside of the ankle)
These injuries can be more difficult to pick up in the early stages. Your physio will be able to help assess and diagnose bone stress injuries by performing a thorough assessment as these injuries can be more difficult to pick up in the early stages. If your physio suspects a bone stress injury you will likely be referred for a scan to determine the integrity of the bone – an MRI scan will pick up these injuries more effectively than an X-ray or CT scan. They may also suggest testing to determine whether nutritional, mineral or hormonal issues are contributing factors.
Otherwise management of bone stress injuries can vary considerably depending on which bone is affected and the severity of the condition, eg stress reaction or stress fracture. However, in all cases the overloading factor should be identified and adjustments made to training or activity to allow the bone to heal. It may be necessary to have a period of non-weightbearing in a cast or boot. In some cases, surgical fixation may be indicated.
Once the injury has healed, muscle strength, foot posture and any other contributing musculoskeletal imbalances will need to be addressed to facilitate a gradual return to your desired activities.