Floyd Landis' Hip Battle

Doctors Explain Why The Tour De France Winner Needs Hip Surgery

(WebMD)  When 30-year-old San Diego cyclist Floyd Landis entered the winner's circle of this year's Tour de France, he didn't shout the traditional "I'm going to Disney World" cheer.

Instead, he told the press he is heading for the hospital where he hopes to get relief from the constant pain caused by an injury to his hip sustained during a 2003 training crash.

"Mechanically, it works fine -- it's just the pain is starting to be unbearable," Landis recently told the Atlanta Journal-Constitution.

That pain is the result of osteonecrosis -- also known as avascular necrosis (AVN). It's the same condition that disrupted the career of baseball and football star Bo Jackson.

What Is Osteonecrosis?

Osteonecrosis develops when blood vessels that feed bones are injured, destroyed, or blocked. This causes a lack of blood circulation to the bone, which can lead to bone death. In Landis' case, the damage reportedly occurred in conjunction with a hip fracture he suffered in 2003.

"When you are young and strong it takes a powerful force to cause a hip to break. And because of that, often key blood vessels in the area can be injured as well," says James Urbaniak, MD, professor of orthopaedics at Duke University Medical Center in North Carolina.

While doctors say some patients may generate new blood vessels to resupply the area naturally, when that doesn't happen, bone can quickly begin to break down.

"Without adequate circulation, the bone simply begins to crumble and die," says Michael Bronson, MD, chief of joint replacement surgery at the Mount Sinai School of Medicine in New York City.

Moving Painfully With Osteonecrosis

In Landis' case, problems were complicated further since the area normally fed by the injured vessels was the femoral head, or tip of the thigh bone, which sits directly inside the hip socket.

"So now, instead of having a smooth, spherical shape to the end of that bone, allowing it to move freely inside the socket, it begins to crumble, and becomes irregularly shaped," says Bronson.

As a result, he says movement becomes like "trying to put a square peg in a round hole."

Urbaniak tells WebMD that over time the socket also can become damaged so that nearly every movement of the leg causes bone to rub against bone. This not only results in significant pain, but in Landis' case, a muscular imbalance that also caused one leg to become shorter.

In most instances, doctors say a secondary arthritis usually develops as well, further increasing pain, and facilitating the need for hip replacement surgery.

"Some people come to replacement surgery as the result of pain from the necrosis alone, others have it when arthritis secondary to the crumbled bone sets in," says Bronson.

In the surgery that Landis reportedly plans to have this fall, doctors will likely replace the end of the crumbling thigh bone with a smooth, artificial tip. They will then remove the old, worn socket and replace that with a mechanical new one.

"The end result will be a smooth moving new joint that is pain-free," says Bronson.

Because the new "parts" are man-made, they don't require the blood supply that bone needs to remain healthy. So even if the blood deficiency to the area remains, the joint is no longer affected.

Did Cycling Wear Out the Hip?

While it may seem as if all that bike riding before and after the accident contributed or even caused Landis' problem, surprisingly, experts say this is not the case.

"Cycling did not wear his hip out. There has never been a scientific study showing that any sport leads to arthritis of any joint. Injury is what leads to arthritis," says Bronson.

Moreover, he tells WebMD that continuing to ride may have actually helped the problem, allowing Landis to maintain a significant range of motion, which in turn allowed him to function better than if he were a couch potato.

Urbaniak tends to agree. "If you have a square peg in a round hole continually causing friction it's going to advance the problem, but that said, the continuous motion of the cycling may actually help lubricate the joint and in that way reduce some of the potential for damage," he says.

While it appears as if Landis' condition is related to his previous training injury, experts say there are other situations that can lead to osteonecrosis, which commonly occurs between ages 30 and 50. A past traumatic injury such as fracture or dislocation is a common cause for osteonecrosis.

Other Causes of Osteonecrosis

According to the National Osteonecrosis Foundation (NONF), some nontraumatic causes of osteonecrosis include extended use of steroids and other anti-inflammatory medications, alcohol abuse, radiation and chemotherapy, and certain medical conditions including lupus, sickle cell disease, HIV infection, and some cancers. Osteonecrosis can also occur from no known reason at all.