Kelsey et al identified risk factors for a stress fracture occurring in a young female cross-country runner. These factors can help identify an athlete who should receive closer monitoring with interventions to reduce the risk. The authors are from Stanford University and other universities the United States.


Mean age: 22 years, with standard deviation 2.6


Risk factors for a stress fracture:

(1) history of a previous stress fracture

(2) lower bone mass in the hip

(3) irregular menstrual cycles (<= 9 menstrual cycles in the previous year)



• The rate ratio for hip bone density was 2.2 for each standard deviation below the mean.


Additional factors that may contribute:

(1) very early menarche

(2) young adolescent


A female runner with one or more of these risk factors should be monitored more closely. If the bone density is low then steps should be taken to increase it.


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