RUNNING INJURIES #1: STRESS FRACTURES
Bony stress reactions are a common injury in the running population. They encompass a wide spectrum of both physical and radiographic presentations. A stress reaction will start as bony oedema and can progress to a bone fracture if loads are not reduced.
A stress fracture “represents the inability of the skeleton to withstand repetitive bouts of mechanical loading, which results in structural fatigue and resultant signs and symptoms of localized pain and tenderness”.
If we look at the running population, the most common sites for a bony stress reaction include: Metatarsals; Tibia; Fibula; Navicular; Neck of Femur. So, the weightbearing bones of the leg that are more susceptible to high loads and repetitive microtrauma.
Bone constantly remodels itself to more efficiently endure external forces, but if the loads applied are too much too soon the process of remodelling doesn’t have time to adequately complete. Additional loading is then applied to susceptible bone tissue, leading to an increased risk of a stress reaction.
Whilst a stress fracture is essentially an overload injury (mechanical loading to bone), it is important to consider the risk factors associated with the development of a bony stress reaction.
Risk factors can be divided into two categories: Extrinsic and Intrinsic.
Extrinsic Risk Factors include considerations such as sport, environment, training, equipment, shoes etc.
Intrinsic Risk Factors refer to individual characteristics such as gender, weight, physical conditioning, muscle and skeletal factors, biomechanics etc.
Extrinsic factors are a critical consideration in the development of a stress fracture; however the development of a stress fracture is influenced greatly by the body’s ability to respond to applied loads.
The forces applied to bone that can lead to a stress reaction include: compression, tension, bending, torsion or shear. The type and amount of force applied to bone will depend on its location, function and individual intrinsic factors.
For Example – Muscles can help to increase of decrease the intensity of load on our skeletal system. Weakness of fatigue in muscles that have a role in shock absorption may allow for an increased load to be transferred to bone, making it more susceptible to a stress reaction.
Management of stress reactions is essentially load reduction. This will allow healing of stressed and weakened bone tissue. It is also vital to address both extrinsic and intrinsic risk factors that make an individual susceptible to injury. This may include: advice on running load and training factors, specific strengthening, running analysis, running technique advice etc.
So, listen to your body. If it’s sending you all the signs it’s stressed, reduce your load. Give it time to adapt and you won’t have to endure the frustration of rest.
If you have any questions concerning stress fractures or are in need of advice, please don’t hesitate to call or email: (03) 5229 3911 OR email@example.com.
Or follow the links for services that may help…
The Injury Clinic.
Warden, SJ., Burr, DB., Brukner, PD. Stress Fractures: Pathophysiology, epidemiology and risk factors.
Romani, WA., Gieck, JH., Perrin, DH., Saliba, EN., Kahler, DM. 2002. Mechanisms and management of stress fractures in physically active persons. Journal of Athletic Training, 37(3), 306-314.