Anatomically the pelvis is somewhat like a box. The front part of the pelvis is attached to the spine by the sacroiliac joint. The hind limbs are connected to the mid part of the pelvis by the hip joint. The colon, urethra, vagina and sciatic nerve pass through the canal of the pelvis.
Signs and diagnosis
Because the pelvis is like a box, it must be broken in two or more places for the pelvic bones to be unstable. The most common cause of pelvic fractures is trauma such as being struck by a motorized vehicle or taking a fall. Affected pets will bear minimal to no weight on the fractured side of the pelvis. If both sides of the pelvis are fractured, the pet may not be able to walk at all. X-rays are required to make a diagnosis of a pelvic fracture. Damage to the sciatic nerve may occur from direct trauma to the pet during the accident or may occur if the nerve gets trapped between fractured bones. The surgeon will also evaluate the urinary tract to make sure that the bladder has not been ruptured. In addition, chest X-rays are made to ensure that there is no trauma to lungs, ribs or diaphragm. Should there be significant trauma to these other organs, surgery may be delayed so that your companion can safely undergo anesthesia and the surgical procedure.
Fractures of the pelvis that involve the hip joint, ilium and the sacroiliac joint usually need to be repaired. Fractures of the hip joint and ilium are usually repaired with a plate and multiple screws. If the sciatic nerve function is impaired, surgery should be performed as soon as possible to release pressure off the nerve, in the hope to prevent permanent damage. Dislocation of the sacroiliac joint is repaired using one or two screws and potentially a pin.
Surgical repair of pelvic fractures has benefits of early pain relief, less collapse of the pelvic canal and impingement on organs that pass through the canal, and relief of pressure off the sciatic nerve if it is entrapped. If present, nerve damage has been reported to recover in 81% of patients that have pelvic fractures. Uncommon complications after surgery may include breakdown of the repair (due to lack of exercise restriction), nerve damage, poor bladder control and fecal incontinence.
For more information on this subject, speak to the veterinarian who is treating your pet.