Sacral Insufficiency Fractures

Sacral Insufficiency Fractures


The sacrum is a triangular shaped bone located at the base of the lumbar spine. The sacrum has five segments that are fused together into one large bone, without the presence of discs between each segment. The bone is classified as making up part of the human pelvis where its function is to diffuse the body’s weight throughout the pelvic girdle. Sacral insufficiency fractures (SIF), as the name refers, are a type of fracture involving the sacrum. They were first described as recently as 1982 by a physician named Lourie. SIF fractures are unique and can occur when the sacral bones are no longer dense enough to handle the stress of weight bearing.

Sacral insufficiency fractures are most commonly positioned parallel to the spine and they are most commonly located in the ala of the sacrum. The sacral ala appear as a pair of wings on the top of the sacrum that fit on both sides between the sacrum’s two halves. These fractures typically cause severe pain in the lower back, pelvis, and even in the hip, groin, and/or the buttocks. The pain from SIF fractures increases upon walking and is somewhat relieved when lying flat. SIFs happen more frequently in the elderly however there are many other risk factors. 

A few other risk factors for sacral insufficiency fractures include certain diseases like rheumatoid arthritis, elevated parathyroid levels, and anorexia, in addition to or in combination with the use of steroids, radiation to the pelvis, fusion of the spine, and hip joint replacement. Sacral insufficiency fractures can also occur in pregnant or breastfeeding women because at this time they are susceptible to osteoporosis. 

Surprisingly, they can occur spontaneously, without a history of fall or trauma to the sacrum. This can sometimes make diagnosing sacral insufficiency fractures a difficult task. Correct diagnosis begins with a comprehensive history and physical exam.  Imaging of the pelvis will then be necessary for further information. Many times normal X-rays will be negative and will not demonstrate a fracture. If a SIF is present a more appropriate image should be ordered via a bone scan, Computed Tomography (CT), or Magnetic Resonance Imaging (MRI).

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Remedy Pain Solutions Blog

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