Hypophosphatemic rickets presenting as recurring pedal stress fractures in a middle-aged woman.

Stress fractures frequently occur from overtraining. When stress fractures recur, underlying metabolic abnormalities should be ruled out. We report a middle-aged woman in whom such an evaluation demonstrated previously undiagnosed hypophosphatemic rickets after she presented with recurring stress fractures in her feet. Treatment with phosphate and calcitriol was associated with clinical improvement that would likely not have occurred without this intervention. Any patient with recurring stress fractures should be evaluated with several screening laboratory tests, metabolic bone x-rays, and a measurement of bone mineral density.