Rare bilateral femoral shaft stress fractures in a female long-distance runner: a case report.

Abstract

Stress fractures are a frequent injury in the running population, commonly affecting the lower limb and foot. The tibia is reported to be the most common site, representing up to 64 percent of stress fractures, while the metatarsals represent 21 percent.1 Femoral stress fractures are less common and can be divided into those involving the femoral neck, condyles or shaft. Those of the femoral shaft are reported to comprise between 2.8 and 21 percent of femoral stress fractures in athletes.1,2,4,5 There is debate as to whether they are more prevalent in the female population.2,6 Bilateral stress fractures have been reported in the tibia and metarsals,1 but have only been reported twice in the femur—one associated with an endocrine disorder, and one associated with bilateral tibia fractures.7,8 There are several factors that put athletes at risk for stress fractures. These include inappropriate training with overuse. Other suspected causes include malalignment, nutritional deficiencies, and endocrine disorders.1,3,5,6,9 Stress fractures in the female athlete also are associated with the female athletic triad, involving disordered eating patterns, amenorrhea, and low bone mineral density.3,6 Here, we report a case of bilateral femoral shaft stress fractures in a 15-year-old female long-distance runner. To date, there has only been one other report of bilateral femoral stress fractures in a medically healthy runner, but that occurred following bilateral tibial fractures.7