Soldiers in basic training who have not been running are at increased risk for bone stress fractures. In this study military recruits in the Finnish army were studied. The goal was to find out how often and what type of stress fractures occur.
Over 1,000 recruits with knee pain during exercise were included. Some had pain in one knee. Others had pain in both knees. Using MRIs the doctors found 141 bone stress injuries in 110 knees of male and female recruits. Seven percent had one bone stress injury. Another 8.6 percent had other injuries such as meniscal tears or ligament injuries. The rest (84 percent) had normal knees.
Most injuries occurred in the medial (inner side) of the knee. Symptoms of pain with exercise or activity started about three months after military training began. The lower leg bone (tibia) or the thigh bone (femur) was affected most often. This is where most of the weightbearing stress occurs.
An increase in how often or how long trainees exercise is the key to stress injuries. Military recruits or healthy adults starting a new or intensive physical activity are at increased risk for bone stress fractures. The authors suggest a routine MRI for anyone with knee pain caused by exercise.