Dear Doctors: I started having pain in my shin while I was training for a triathlon. My doctor thought it was shin splints because the X-ray came back normal. The pain continued, so they did an MRI and found a stress fracture. What is that, and how is it different from a regular broken bone?
Dear Reader: A stress fracture is a small, hairline crack that develops in a bone, typically from overuse. It occurs when repetitive force outpaces the body's ability to repair microscopic damage to a bone. These types of injuries are common among athletes, particularly in runners. By some estimates, they account for up to 20% of all sports injuries.
A stress fracture usually occurs in the lower extremities, most often in the shinbone, the bones of the feet or in the heel. The damage can develop on the hard, outer surface of the bone or within its internal structure. Although these injuries can seem less severe than a complete fracture, which extends through the full thickness of the bone, they must still be taken seriously. Despite the seemingly small size of the break, the area needs to heal and form new bone. Many stress fractures heal within six to eight weeks, although some can take much longer.
In the early stages of a stress fracture, the symptoms can be mild enough to go unnoticed. For many people, awareness of the injury begins with the persistent, localized pain that you experienced. This will usually get worse during physical activity and, in the early stages, may improve with rest. As the injury progresses, however, pain may persist even at rest. Many people develop swelling at the site of the fracture. The area itself is often tender to the touch.
Diagnosis begins with a physical exam. Because the break is so thin and small, an X-ray may not be able to detect it. This is particularly true with a newer injury, when symptoms can be similar to those of shin splints. Because of this, the MRI that you underwent is often the most useful imaging test for detecting an early stress injury.
Treatment depends on the location of the fracture and how severe it is. Most important -- and we're very sorry, but it's nonnegotiable -- is rest. You will be asked to stop the sport or activity that led to the fracture and limit stress on the affected bone while it heals. For some people, ordinary walking may be permitted. For others, any weight-bearing movements may be restricted. It all depends on the site and severity of each person's injury.
Acetaminophen may be used to help manage pain. A compression bandage can help reduce swelling. In some cases, a cast to immobilize and protect the damaged bone or crutches to keep you from using the affected limb may be recommended. It is important to understand that returning to activity too soon can not only delay healing but may make the injury worse. Be sure to follow your doctor's guidance throughout your recovery.
(Send your questions to [email protected], or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)
