Stress fractures are far more common in the lower limb (~95%) than in the upper limb 5. Insufficiency fracture: normal stresses on abnormal bone Etiologyįatigue fracture: abnormal stresses on normal bone PathologyĪ stress fracture is the final stage of a stress injury and occurs if the bone fails to withstand a repetitive, cumulative loading force and is no longer capable to mitigate that loading stress with its own healing capabilities and breaks 7. In the lower (weight-bearing) limb, there is often a history of a recent increase of physical activity or significant alteration in the type or duration of normal athletic activity. Stress fractures normally present with worsening pain with a history of minimal or no trauma. The following conditions increase the risk of a stress injury 8: Insufficiency fractures occur more in women and older people 7,8. Epidemiologyįatigue fractures are common in athletes, especially runners and military recruits. Some authors use the term stress fracture synonymously with fatigue fracture, and thus some caution with the term is suggested.
A pathological fracture, although a type of insufficiency fracture, is a term in general reserved for fractures occurring at the site of a focal bony abnormality.
