Pelvic stress factors are among the most common overuse injuries sustained by long-distance runners, and they affect everyone from recreational athletes to world-class competitors, male and female. Many physical and environmental risk factors can trigger a stress fracture of the pelvis, but while the causes are often small, the effects of a pelvic stress fracture can be huge. Pelvic stress fractures demand rest.
Physiological Factors
Overuse injuries strike endurance athletes such as marathon runners because of the demands of the sport and the makeup of the athletes. Distance running requires athletes to perform the same movements repeatedly, subjecting the same muscles to repeated movements and subjecting the same joints to sustained impact. Making matters worse, runners often condition their minds to ignore pain, driving them to push muscles and joints to the brink of injury. When a runner's muscles tire, he often forces his bones to compensate by bouncing higher in the air during his stride, forcing the pelvis to absorb more impact. A runner might also be forced to compensate in his stride for imbalances in his posture or leg length, again forcing the pelvis to absorb greater impact.
Training Factors
When a runner suddenly increases her total mileage by more than 10 percent per week, or ratchets up the intensity in her training, she often skips the body's normal acclimation process and puts more strain on her pelvis than it can handle. Running on hard surfaces such as roads and sidewalks, especially on cambered road surfaces that slant to the side to allow water drainage, puts a marathon runner at greater risk for a pelvic stress fracture. While the rigors of training already strain a runner's pelvis, the strain can become even more significant when a runner suffers from a calcium deficiency, weakening the bones, or an eating disorder, depleting body fat used to cushion joints.
Symptoms
Many runners often confuse the beginning stages of a pelvic stress fracture with a simple muscle pull. However, unlike the pain of a muscle pull, the pain of a stress fracture will not subside during a run nor will it loosen up with stretching. When a runner sustains a pelvic stress fracture, he might first feel a deep, aching pain that remains localized in the hip. However, as the injury remains untreated, the pain can spread to the lower back, groin and thigh as the body attempts to compensate for its weakened joint.
Treatment
As with an injury, the best treatment for a pelvic stress fracture is prevention. Runners should observe the 10 percent rule -- not increasing the frequency, duration or intensity of training by more than 10 percent each week -- to guard against a pelvic stress fracture. Runners can also run on softer surfaces such as grass or crushed limestone trails to lessen the impact absorbed by the pelvis. When a runner does develop a pelvic stress fracture, she should visit a doctor for diagnosis and rest from running and other weight-bearing activities for a week or two. More severe stress fractures may force a runner to walk with crutches, removing all weight-bearing on the injured hip, and possibly even undergo surgery.
References
- OrthoSuperSite.com; Evaluation and Management of Stress Fractures of the Pelvis and Sacrum; Robert G. Hosey, et al.; April 2008
- Over40Runner.com: Stress Fractures in the Runner
- BeginnerTriathlete.com; Common Causes of Hip and Pelvic Pain in Runners; Andrew Gregory; January 2008
- Rice University: Calcium, Bones and Stress Fractures
- Universal Sports; Revived Keflezighi Claims Third U.S. Cross-Country Title; Dave Ungrady
