Case 6 - “Stressing Me Out”
A high school cross country runner begins the season with high hopes, but soon finds that her runs are being cut short by a throbbing pain in her left shin. When she rests for a day or two the pain gets better, but it then returns when she resumes full activity. Her coach doesn’t want this nagging injury to become serious, so the runner is sent to the sports medicine physician. The doctor makes the diagnosis based on her symptoms and the physical exam but orders x-rays and an MRI just to be thorough.
The first x-ray image shows no fracture or other acute abnormality. (The area of the runner’s pain is indicated by the red oval). The second set of images from the MRI, however, reveal the cause of the pain. Figures A and B are coronal (front) images of the lower leg. There is a small amount of edema (excess fluid) along the anteromedial (front/inside) of the tibia (shin bone) as shown by the yellow arrows. This edema (yellow arrow) can also be seen on the axial (cross-section) image in Figure D. This edema corresponds to the area of the patient’s pain. Importantly, there is no edema within the tibia bone itself (yellow asterisks) which would indicate a more severe stress reaction. Even more importantly, there is no fracture line that would indicate a stress fracture.
DIAGNOSIS: Medial Tibial Stress Syndrome
Medial Tibial Stress Syndrome (also known as Shin Splints) is a common malady for athletes. Shin splints most often present as pain along the front-inside (anteromedial) shin, but some patients can experience pain along the front-outside (anterolateral) or along the back-inside (posteromedial) shin. Stress reactions of the tibia constitute a spectrum of injuries ranging from a purely soft tissue injury (as in this case) to a well-defined stress fracture. Obviously, the more severe the injury, the greater the recover time. Predisposing factors are the same as most overuse injuries: rapid increase in the duration or intensity of runs, incorrect or insufficient footwear, or inherent body factors such as flat feet or low bone mineral density. Addressing these predisposing factors can be used to prevent shin splints. Treatment of shin splints is similar to other overuse injuries: rest, anti-inflammatory measures (such as ice or non-steroidal medications), compression (including compression calf sleeves), and appropriate footwear and orthotics (if necessary).
Dean Thornton, MD
Dean is a Musculoskeletal Radiologist with Radiology Associates of Birmingham and a Clinical Associate Professor of Radiology at UAB. He works with many local orthopedists and sports medicine physicians. He also likes to run.
Inside the Runner uses medical imaging to offer readers a chance to see what is going on inside their bodies when something breaks down. From fractures to tendonitis to muscle injuries, this series explores the imaging studies used to help doctors and other medical professionals treat running injuries.