An avulsion fracture is a bone fracture which occurs when a fragment of bone tears away from the main mass of bone as a result of physical trauma. This can occur at the ligament due to the application forces external to the body or at the tendon due to a muscular contraction that is stronger than the forces holding the bone together. Generally muscular avulsion is prevented due to the neurological limitations placed on muscle contractions. Highly trained athletes can overcome this neurological inhibition of strength and produce a much greater force output capable of breaking or avulsing a bone.
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