Author: Rohan Moffatt, MBBS
Co Author #1: Dr. Andrew Tucker
Editor: Young Yoon, MD
Stress fractures are common injuries seen in the running athlete. Femoral stress fractures are rare occurrences and account for 7-8% of stress injuries [1,2]. Fractures of the proximal femoral shaft are found to occur at a rate of 18% of all femoral stress fractures . The average time to diagnosis ranges from 13-14 weeks  when radiographs, bone scan and computer tomography are the only available investigative tool. With the advent of magnetic resonance imaging, the increase sensitivity and specificity permits earlier diagnosis and better delineation between the causes of hip pain . The following case highlights the complexity of arriving at a diagnosis when assessing hip pain in endurance runners and the need to have a high clinical suspicion for stress fractures.
Eighteen year old male cross country student athlete presented with dull right hip pain for two weeks. His pain was exacerbated by running and was alleviated with two weeks of activity modification. This included non-weight bearing cross training on the stationary bike and elliptical machine. He attempted to run after the two weeks of cross training but had to stop due to resumption of pain. The pain was located on the lateral aspect of the right hip and radiated down the thigh. He denied any traumatic incident while running. He usually runs up to sixty five miles per week. He reportedly increased his weekly mileage by an additional five miles prior to seeking medical attention. He had a history of right hip flexor muscle strain many years ago which completely resolved. He mentioned that his older brother, who is a collegiate cross country runner, experienced a similar lower extremity pain two years prior.
The student athlete's gait was normal. The heights of both iliac crest were symmetrical. There was some discomfort with one leg hop test. Range of motion testing of the right hip was normal, painless and comparable to the left side in the seated position. Lower extremity strength testing was normal with no recreation of pain. There was excellent right hip range of motion while lying supine with fully forced internal rotation being painful. There was no pain with sitting up or with bilateral straight leg raise testing. Torque testing of the right hip was normal. Fulcrum test was negative.
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