Monday, September 22, 2014
Bo knew football. Bo knew baseball. Bo knew hip dislocation. Now Dennis Pitta knows what Bo knew…hip dislocation leads to badness. For the second time in two years, Mr. Pitta, the Baltimore Ravens tight end, dislocated his hip and required surgery to repair the damage. A year ago, the hip injury occurred while being tackled. This time, he twisted on the field and went down in a heap without being touched, the hip popping out of joint without significant trauma.
In 1991, Bo Jackson, then of the Oakland Raiders, was tackled in a playoff game and felt his hip pop out of joint. Even with having the dislocation reduced, or having it put back into place immediately, and even with surgery and rehabilitation, he developed avascular necrosis of the femoral head (the ball of the hip joint). This is a common complication of hip dislocation that occurs because of hip has been poorly structurally engineered. Some of the blood supply to the femoral head comes from arteries that have to travel across the joint from the acetabulum (the socket of the hip joint) to the femoral head. When the hip dislocates, that blood supply is lost and the potential exists that the femoral head will not get enough oxygen and nutrients from other arteries to survive. This is called avascular necrosis (a=without + vascular=blood vessels +necrosis=death) and it damage the femoral head no matter how good the treatment is or how fast the hip is repaired. Mr. Jackson underwent hip replacement surgery and was able to return for a brief time to baseball but soon his career was over.
For Mr. Pitta, surgery and rehabilitation for his first hip dislocation went well and he was able to return to play football late in the season. Dislocation number two raises questions about the potential for him to return a second time.
The hip is a strong structure and it takes a significant amount of force to cause a dislocation. Aside from the bony protection of the acetabulum and the five large ligaments that help stabilize the hip joint, the angle that the femoral head enters the acetabulum provides even more stability. Most often, hips are dislocated in car wrecks, where the dashboard is driven into the knee of the driver or front seat passenger. By sitting with a bent knee the direction of the force drives the femoral neck through the back of the acetabulum, breaking that bone.
Aside from avascular necrosis and arthritis, which are long term complications, the big risk in the acute situation is damage to the sciatic nerve, the large nerve that leaves the back and runs through the buttock, behind the hip, to supply the leg. When the hip dislocates posteriorly or toward the back, it can damage the nerve in a variety of ways, from having generalized swelling inflame the nerve to specific damage done because of bony fragments injure the nerve.
Mr. Pitta required surgery again to repair the injuries and time will tell whether he will escape the complications that can plague hip dislocations. Most certainly, his second hip dislocation occurred because the structures that held his hip in place, the muscles, tendons ligaments and joint capsule had loosened. He had the bad luck to have his injury witnessed by an audience of thousands in the stadium and millions more in the television audience, but the injury could have just as likely happened in a parking lot, twisting to get out of a car or playing in the backyard with his family.
Dennis Pitta now knows what Bo knows. 20 years of medical progress still cannot guarantee perfect healing. Injury and trauma have a way of humbling those in the medical profession. Even with the best care, the body cannot always be put back together like it was before. There are complications that cannot be prevented. There are injuries that cannot be completely rehabilitated. Sometimes badness happens.
Xray image attribution: www.wikiradiology.com
This entry was tagged arthritis, avascular necrosis, Bo Jackson, Dennis Pitta, hip dislocation, sciatic nerve