March 26, 2015 at 10:24 AM
A stress fracture is an overuse injury to the bone caused by repetitive loading on the area. They usually come on over time with repeated impact or load to the same area such as with distance running and often the stress reaction or signs of overload has started long before you get significant symptoms.
95% of stress fractures occur in the lower limb because this is the area most likely to beoverloaded during impact exercise. The most common sites are the tibia, fibula (lower leg bones) or metatarsal’s which are the bones in your forefoot. Recent research is showing neck of femur (hip) stress fractures appear to be increasing in incidence also.
Some predisposing factors to getting a stress fracture include
Poor biomechanics and muscle imbalances
People with poor bone health are also more at risk of developing a stress fracture. Your bone health can be affected if you are a female due to menstrual and hormonal irregularity, if you have diabetes or thyroid disease and if you are a smoker or use medications such as oral corticosteroids.
Diagnosis of a stress fracture
Your Physiotherapist will take a thorough history to identify any of the above risk factors as well as carry out physical tests such as palpation for localized bony tenderness and impact tests such as hopping.
If a stress fracture is suspected from the clinical exam referral for an MRI scan may be ndicated. This is the investigation of choice and can show stress reaction in bone early – MRI scans have been shown to be accurate within 72 hours of pain. A stress fracture will only show up on a plain x-ray if it is very advanced.
Management of Stress fractures
The good news is that most people who suffer from a stress fracture will make a complete recovery however it does take time and following the programme set by your physiotherapist is essential.
The first part of the recovery is Unloading
This will involve stopping the aggravating activity and depending on the severity of the stress reaction/fracture it may require a period of non-weight bearing on crutches. Non-impact cardio exercise such as swimming or cycling can usually still be done to keep up fitness levels.
Your physiotherapist may also use manual therapy such as massage to unload the stress on the bone by releasing the soft tissue structures that attach around the area.
The next phase is gradual Reloading.
It is important to address any biomechanical deficiencies at this stage, for example in a stress fracture of the neck of femur (hip) retraining the gluts is important and in tibial stress fractures the deep muscles of the calf often need to be strengthened. Core strengthening with a Clinical Pilates programme is an excellent way of addressing these underlying issues to ensure the stressed area is not over loaded again.
The actual reloading of the bone needs to be gradual and pain free. Weight bearing is important in bone healing. As pain allows in a moderate to severe stress fracture walking can be introduced to the programme at 6-8 weeks. This can then be increased to interval training (jog-walk-jog) then gradually back to jogging.
Any reloading programme must have rest days, a ratio of 1 day on and 2 days off is usually recommended and nothing should be increased by more than 10% per week.
As with most injuries detecting any overload early is the best way to ensure you are not out of action for too long if you are new to running or ramping up your training and are noticing pain in the same area each session consult your physio for some early advice.