Stress fractures occur when there is a small break in the bone. Unlike an acute fracture, these types of injuries develop overtime, especially when there is repeated stress to a localised area. They can occur in any bone in the body where there is overuse, but the feet and ankles can be more at risk due to the amount of force absorbed with weight bearing. Females have 1 ½ – 2 times more risk of developing a stress fracture compared to males.
Bones are constantly undergoing a remodelling process, where new bone develops and replaces old bone. In stress fractures, there is a reduced ability for the bone to cope with the demands of loading. This can lead to the breakdown of older bone occurring at a faster rate than the body’s ability to repair and replace it. Stress fractures can occur in people with healthy or weak bones. Typically in people with healthy bones, these fractures only occur with an excessive increase in activity and can be referred to as fatigue fractures. In people with weaker bones, stress fractures can be sustained with normal loading, and this is known as an insufficiency fracture.
Below are some factors that may increase your risk of developing a stress fracture:
– Decreased bone density due to an underlying condition – this may include vitamin D, calcium deficiencies or osteoporosis/osteopaenia
– Poor conditioning, which can include a rapid increase or return to activity with inadequate rest
– Improper training techniques
– Changes in training surfaces, particularly to harder surfaces
– Footwear with poor shock absorption
– Altered biomechanics may lead to increased loading in areas causing fatigue and stress on bones
At Erko Podiatry, we will take a thorough history which may involve enquiring about your general health, activity levels and training history, and will perform a biomechanical assessment of the lower limbs. We may send you for imaging if we suspect a stress fracture which includes x-ray and an MRI if required.
How to treat stress fractures
– Rest and restricted weight bearing is an essential part of management as this will prevent further breakdown of the bone and allow healing to begin. This may include immobilisation with a boot which may take 4-8 weeks or longer, depending on the severity and location of the fracture
– Footwear recommendations
– Exercise programme to prepare you for a gradual return to activity – this may include weight bearing strengthening, and functional exercises. This programme will be graduated, to avoid stressing the bone further and allowing it to strengthen.
– Orthotics may be recommended to address biomechanical abnormalities which have contributed to abnormal/increased loading
Stress fractures can occur in any bone of the foot, however the most common sites affected are the metatarsals (long bones connecting the toes), navicular (midfoot bone), calcaneus (heel bone). They can also occur at the talus, tibia and fibula which are the bones that form part of the ankle.
Females are more prone to stress fractures due to a number of factors including reduced bone mineral density, reduced muscle mass, and hormonal changes related to menstruation. Those who suffer from a combination of menstrual irregularity, decreased bone mineral density and low energy availability (from nutritional deficiencies or disordered eating), are significantly at risk of developing stress fractures. The interrelationship between these conditions is known as the Female Athlete Triad, and is relatively common in young females participating in sport.
Stress fractures can worsen without treatment, becoming more painful and debilitating. If left untreated, avascular necrosis (bone death) may occur, potentially leading to permanent changes to the bone and it’s joint surface. This can cause chronic pain, and increase the risk of developing arthritis in the area of injury. If sufficient healing fails to occur, surgery may be the only option for treatment.