Physicians are seeing an increasing number of patients with stress fractures as a result of the emphasis on physical fitness in the general population. Elderly persons also are exercising more than in the past, either to keep fit or as part of a therapeutic regimen for a particular health problem and, as a result, they too sustain stress fractures. In elderly patients, however, stress fractures may be a result of lack of regular physical activity or the inability of the musculoskeletal system to withstand the stress of exercise. Stress fractures in some elderly patients actually may be insufficiency (fatigue) fractures because they affect bone with lower resistance. Carpintero and colleagues evaluated the incidence of insufficiency fractures in the elderly population and associated factors, such as exercise type, symptoms, diagnostic delays and treatment.

The medical records of 6,650 patients who visited an orthopedic care unit over a six-year period were reviewed to identify the incidence of stress fracture in the elderly. Patients were included in the study if they were older than 60 years of age and had a definitive diagnosis of insufficiency fracture as established by findings on radiography or scintigraphy. Other factors evaluated included gender, type of exercise, examination findings, bone and side affected, delay in diagnosis, bone mass, treatment and treatment outcomes.

All of the 30 stress fractures that occurred in the study subjects were in the lower limbs, primarily the tibia. Thirteen of the patients (43 percent) were men, 17 (57 percent) were women. Brisk walking was the cause of injury in 17 patients (56.6 percent), running was the cause in 10 patients (33.3 percent) and hunting was the cause in three patients (10.0 percent). In most cases, studies of bone mass were within normal limits for the patient's age but were lower than that of a young person. In all cases but one, pain was the symptom that prompted the physician visit but usually only after pain relief was attempted at home. As a result, diagnosis was delayed between one and nine months in most patients, with an average delay of 4.9 months. The average delay in initiating physician contact after the onset of symptoms was three months.

The authors conclude that elderly patients involved in any type of physical activity on a regular basis may sustain insufficiency fractures. Decreased bone mass was implicated in the greater percentage of these fractures in women. Stress fractures may occur in both extremities and in the spine in younger patients. However, in the study population, all cases of stress fracture occurred in the lower extremities. Therefore, lower extremity pain in an elderly patient should be evaluated and, if the patient exercises regularly, a diagnosis of insufficiency fatigue fracture should be considered. Prompt diagnosis permits nonsurgical treatment with immobilization and reduced activity and, ultimately, an improved outcome, whereas a delay in diagnosis can result in the need for surgical intervention. Physicians should encourage appropriate exercise for patients over 60 years of age but should also be aware of the possibility of stress fractures and the need for prompt diagnosis and treatment.