Originally published in The Ottawa Citizen August 17, 2004
Original Title: The thin white line
The pressure and stress exerted upon the feet and lower extremities can be substantial. A common class of sports-related injury is stress fractures.
Stress fractures can be difficult to diagnose because they may not be seen on an X-ray immediately after an injury.
It should be suspected when the patient states that he or she can identify a specific region of bone pain. This is especially telling if there is a recent history of a new exercise routine or program, or an increase in exercise intensity or level.
Track and field sports account for more than 50 per cent of the stress fractures in men and 64 per cent in women. Platform diving and rowing, although not considered high-impact sports, may lead to stress fractures especially in the metatarsal bones of the feet (the bones that connect the foot to the toes) and the ribs. Softball, hockey, swimming and golf are not likely to cause fractures.
Although upper extremity and rib stress fractures do occur, they are much less common than the lower extremity stress fractures. The focus for this column will be on bones of the lower leg (tibia and fibula) and the feet.
The bones most likely to be affected are the tibia (shin bone) and the metatarsals. Fractures of the pelvis, femur (thigh bone), fibula (bone running parallel to the tibia in the lower leg) and some other bones of the foot occur less commonly.
The fracture is due to the repetitive injury of the bone usually from the pounding nature of the activity. This causes microfractures to form.
The injured or microfractured bone tries to repair itself. However, if the same activity continues, the microfractures coalesce into a stress fracture. It is like chipping a block of ice. Small cracks appear each time. Eventually, with enough chips, the ice will crack. The bone cannot keep up with repairing the damage and eventually cracks from the strain.
Although athletes do suffer from these fractures, non-athletes or deconditioned people beginning a new exercise program are at high risk for injury. Women are more likely than men to develop fractures. Sixty per cent of people who suffered from a stress fracture will develop another when they resume the same exercise regimen.
Half of all stress fractures in children and adults occur in the tibia, usually because of excessive running or jumping. Metatarsal fractures account for another 25 per cent of stress fractures and commonly affect the second and third metatarsal bones near the toes.
Other areas affected to a lesser extent are the fibula and a bone in the midfoot called the navicular bone.
Endurance athletes can develop fractures of the femur. They are rare but they have a high incidence of not healing.
Signs and symptoms that aid in the diagnosis of stress fractures include a dull ache or pain localized to a specific site in the lower extremity that worsens with weight bearing or exercise. The area may be swollen but the tell-all sign is pain with direct palpation.
A fracture of the femur can present as pain in the groin, front of the thigh or knee. The hip is painful to move.
X-rays, although the first test to be done, may not show the fracture; it may never appear on the X-ray, or it can take from two to 10 weeks before it can be seen.
A nuclear bone scan is able to detect early stages of stress fractures. MRI is better than regular X-ray tests for diagnosis and can outline the fracture better than a bone scan.
Nonsurgical interventions for the treatment of stress fractures include using ice, nonsteroidal anti-inflammatory drugs (NSAIDs) and resting the bone for several weeks or until the pain resolves. Warm-ups and stretching prior to resumption of activity is recommended. The exercise regimen should be gradually increased to avoid a new fracture.
Injury prevention includes pre-exercise stretching with a warm-up. This is especially important for tibial stress fractures. Light footwear and a smooth soft running surface such as a dirt path or grass will also reduce the fracture risk.
Some injuries may require casting or a special orthotic shoe. There is some evidence that using an aircast helps the athlete return to the activity sooner. Certain types of femoral fractures may require surgical repair. Each bone type has its own set of treatments and is best discussed with your doctor.
In a previous column on hyperpigmentation, I erroneously equated the disease neurofibromatosis with the Elephant Man’s disease. In fact, Joseph Merrick had Proteus Syndrome. My thanks to Susan Brassington for correcting me on this point.
© Dr. Barry Dworkin 2004