Bennie came to us last week as a very painful unhappy kitty. Upon physical exam the pain was found to be mostly generalized to the right hip area. It was decided that because of the level of discomfort he was in he should be given pain medication, sedated and have radiographs (x-rays) done. The radiographs showed that Bennie had an uncommon condition called "idiopathic necrosis of the femoral neck" with a resulting break of the right femoral head. What this means is that for some reason Bennie's body breaks down the bone matrix just beside the hip joint making that area very weak. It was also noted that the same area on the left side was less dense on radiograph than the other normal bone. When doctors look at radiographs we position them as if the cat is standing on his hind legs facing us, so his right will be on our left. These kitties are normally young male cats who appear perfectly normal and then one day when doing a normal activity like walking up the stairs or jumping down from the couch they become very painful and lame because the end of the femur bone breaks off. To make matters worse, the unbroken leg that is trying to compensate will normally break soon after due to the extra pressure on it and it's own bone weakness.
Bennie needed a very specialized surgery so we called in Dr.Kim Murphy a Board Certified Surgeon to preform a bilateral femoral head and neck excision arthroplasty. Unlike most other hip surgeries, the head of the femur is removed but not replaced. It is allowed to heal and develop its own tough fibrous scar tissue so that the joint is no longer bone−to-bone. Although this surgery is typically classified as a salvage procedure it is the best option for cats with this type of disease related injury. Unfortunately cats bones are to small to properly support a typical hip replacement like those available for humans or large dogs.
After his surgery Bennie was a model patient. You could immediately see improvement in his movement and the reduced level of medication we needed to control his pain. He has several weeks of physiotherapy and after care to still get through but Bennie will soon be able to run and play again. Because of slight limb shortening and some loss of range of motion, some abnormalities in his gait will always persist. However he will now be able to continue leading a happy active life.
Thank you to Bennie's family for generously letting us share his story.
Written by Angelina Johnstone RVT