The femur is the largest bone in the body, and it’s monstrously strong. It’s almost two kinds of bone, really: theshaft, which gets its strength from being an almost rigid cylinder, and the neck. The neck is very sophisticatedin structure. Because of its curve and the stress it has to endure, it’s built like a bridge, with bone laid down incomplicated arches. It’s a spongier kind of bone than in the shaft, but still very strong for what it’s designed todo.
But as mighty as this bone is, stress fractures can be its undoing. Stress fractures are almost invisiblecracks that invade the bone (for an extended discussion of stress fractures, see chapter 4, “The Lower Leg”)and in the worst scenario can spread all the way through it, actually severing one part from another. Thestress fracture can become a real fracture, and it’s not unusual for it to knock off the head of the femur. Thatcan be devastating. In young people especially, the severed portion can lose its blood supply and die. You canbe looking at a hip replacement at age twenty-two.
The problem is made more difficult by the fact that stress fractures are tough to spot because theydon’t have any particular symptoms. The strongest diagnostic criteria are that there aren’t any diagnosticcriteria. You have pain somewhere in the thigh, usually the upper part. It’s worse when you exercise, betterwhen you don’t—well, that sounds like a lot of things. You try all the treatments you know, and nothing works.Finally you go to a doctor who, after hearing your frustrating story, gives you an x-ray—still nothing. Finally,if you’re lucky, the light dawns, and your doctor gives you a bone scan. And there it is, a tiny crack that you can’t believe could cause so much trouble.
t can. We see femoral stress fractures in run-ners and aerobic dance teachers primarily (not stu-dents—the number of classes makes a difference),at a rate of two or three a year. They show up withsome frequency in the military, which is so cautiousabout them that you’ll find yourself in bed before youknow it and after that on crutches. They seem to becaused by overuse—running, jumping, perhapschanging surfaces and terrains—and training errors,trying to do too much too soon. They can show upanywhere in the femur, from the neck all the way downthe shaft, and we really don’t know why it’s one placeand not another. (You can also get stress fractures ofthe pelvis where the muscles begin. These, too, areoften missed.) They all take a long time to heal, some-times as long as six to nine months, and, if the frac-ture is in a particularly hazardous spot, it may requiresurgery to pin the bone together.
|+ Hip Dislocation, or Not? +|
|t is common to feel as if your hip were dislo-cating, when it’s probably just the iliotibialband tendon snapping over the greater tro-chanter. The tendon can be so tight, and is sobig and prominent, that when it snaps it canfeel as though your hip is shifting in position. Itisn’t. But the muscle and tendon are, and theabrupt change can be striking and disconcert-ing. |
Treatment involves stretching and strength-ening the muscle. Best to see a doctor aboutit.
+ What to do about it + See a doctor, and once you have, it’s vitally important to do what you’re askedto do—in most cases, not much of anything. That’s what makes things hard. Active people don’t like to donothing. It’s hard enough to get active people to slow down, much less stop doing their favorite activity, butthat’s just what you have to do with a femoral stress fracture. You have to make the area free of pain so thebone can start to heal, and that may involve crutches and a wheelchair around the house. No fun. The ruleof thumb here is that if it’s not hurting, you’re not doing anything wrong.
Then, when the pain is gone, try to get back to as much activity as you can without hurting the areaagain. The tricky thing about stress fractures is that the bone originally broke because it wasn’t strongenough for the demands you put upon it. So it’s not enough simply to let it heal, you’ve got to exercise it tothe point where it’s strong enough not to break when you impose those demands again but not to the pointthat you reinjure it while trying to rehabilitate it. Risky business.
o, the tip-off is activity-related pain in the thigh that you can’t put a finger on and that doesn’trespond to treatment. If that describes what’s happening to you, see a doctor.