Avulsion Fractures


Structure of the break: This fracture is always associated with a muscle. A fragment of bone is pulled away from the main body of the bone as a result of excessive force being applied to the tendinous or ligamentous attachment to the bone, as a result of the over contraction of the muscle.



Diagnosis: An X-ray of the area is usually a suitable diagnostic tool, although through taking the patients history a Doctor can often speculate that the type of fracture will be an Avulsion fracture.



Cause: This type of fracture is common in athletes and children. Athletes may over exert their muscles, causing them to contract past a point that is safe, causing the bone at the insertion point of the muscle to be broken off.

  In children, the bone is likely to fail before the ligament or tendon, due to the presence of growth plates, which do not provide an as stable attachment as fully developed bone.



Treatment: In adults the fracture is often treated like a sprain or muscle tear, unless the distance between the body of the bone and the fractured fragment is more than a few centimetres wide. In this instance surgery is required to reattach the bone and muscle.

  In children the treatment is of greater importance, as improper treatment could result in the stunting or abnormal growth of the affected limb. Surgery may be required to re-align the growth plate.


Avulsion Fracture of Lunate Bone



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Small Avulsion of the Cuboid Bone



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 Iliac Spine (Hip) Avulsion Fracture - Magnified



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Types of Fractures: Transverse / Oblique / Spiral / Logitudinal / Green Stick / Comminuted / Torus/Buckle / Impacted / Hairline / Compression/Crush / Avulsion




Fig.1 – Courtesy of AMagill, flickr

Fig.2 – Courtesy of Vanalstm, wikipedia

Fig.3 - Courtesy of Radswiki