Sometimes I wish I could slice open the skin that covers my knees so I could poke around inside a bit. Without pain, of course. Without spilling any blood or other vital juices. And only if I could use magic to close up all the tissue when I was done. If I could do that, I’d love to get a good look at the ends of my thigh and shinbones. These bones meet at the knee. Their complex conjunction — the stuff that joins the two together — is the knee. What I would hope to see in mine would be a glistening white padding over the knobby bone ends, a coating smooth as the finest china, thick as white chocolate covering some sweet harder substrate.
That’s what you see in great knees, those in the best condition, which I suspect mine are not. My knees are 49 years old, and they often crackle and pop. Sometimes they ache when I run. At other times, random painful twinges shoot through them.
I try to be optimistic. An optimist can look at human knees and marvel at their prodigious competencies. The largest, strongest, and heaviest joints in the body, they not only support most of our weight, but they enable us to lope and crawl and stride and skip and tiptoe and otherwise perambulate. Viewed through a darker lens, however, knees also rank among the most vulnerable of body parts. They’re the anatomical site most often treated by bone and joint doctors, according to the American Academy of Orthopaedic Surgeons. Americans visit doctors’ offices close to 11 million times a year because of some kind of knee problem. Over the course of the 1990s, knees overtook hips to become the joint most often replaced by surgeons. First done in 1968, the procedure involves cutting out the ruined knee surfaces and creating a substitute hinge made out of metal and plastic. Total knee replacements more than doubled over the past decade, from 129,000 in 1990 to 267,000 in 1999. Some medical authorities have estimated the number will almost double again over the next 30 years, climbing by 454,000 such operations per year by 2030.
Knees can fail in so many ways. The four fibrous ligaments that lace the shin and thighbones together can be stretched to the point of ripping or snapping. The forwardmost of the two ligaments that crisscross behind the kneecap (the anterior cruciate ligament, or ACL) is particularly prone to injury; more than 95,000 of them in the United States tear every year, according to the orthopedic surgeons’ organization. “People often tear the ACL by changing direction rapidly, slowing down from running, or landing from a jump,” the surgeons’ website informs visitors. “You might hear a popping noise when your ACL tears. Your knee gives out and soon begins to hurt and swell.”
That sounds so decorous, genteel, compared with my experience with ACL destruction. This memory is pinned like a slalom pole to a ski slope in Keystone, Colorado, on the morning of February 8, 1997. It’s a beginner’s slope, and it glitters in the sunshine of a lovely day, but it’s too steep a slope for someone like me who’s spent no more than three hours on downhill skis in the course of her entire lifetime. I start down it, but within a very few seconds realize I’m heading — too fast! — for a grove of trees, so I shift my weight in a clumsy attempt to lurch away from danger. I lose my balance, and as I hit the snow my left leg folds up beneath me at an unnatural angle, a move that detonates a small atomic bomb of pain. Ground zero is my knee, but the pain mushrooms out; the shock wave brutalizes every neuron in my body. Along with the pain, I feel horror. I still feel it today in this memory. It’s the horror of knowing you’ve just made your body do something unspeakable, something that has broken it.
I never did hear the revolting popping sound that’s said to be on the soundtrack of so many ACL disasters; but within moments, the swelling had transformed my trim normal knee into a fat person’s knee, bloated and alien. In the days that followed, along with the pain, waves of nausea washed over me every time an imprudent move reminded me of how loosely my lower left leg had become connected to its upper half. (Orthopedic examination revealed that I had also ripped the collateral ligament that secures the thigh and shinbones along the inside of the leg.) At times it felt as if my shin and foot were connected to the rest of me by nothing more than skin, as if a simple push might break them off.
Little by little, the feeling of vulnerability receded as the side ligament healed. In contrast, anterior cruciate ligaments never heal, my doctor informed me, and many orthopedic surgeons perform surgery to reconstruct torn ACLs. For the repair material, they harvest a strip of tendon from some other site in the body, such as the kneecap or the hamstring. But reconstructive philosophies in the spring of 1997 were in flux, according to my orthopedic surgeon, who recommended waiting a couple of months to see how stable my knee became. “It looks like a third of all patients can resume their normal activities even if they don’t have the surgery. A third are fine if they modify their lifestyle somewhat. And a third wind up having so much instability that they need to have the reconstruction,” he told me.
I wound up in the lucky group. I got some occupational therapy for a few weeks but had no surgery. Six months later, my only reminder of the accident was a dull throbbing after a long day on my feet. Even that disappeared after a few more months. My doctor warned me that I appeared to have injured the edge of the meniscal cartilage in my left knee. It might heal on its own, or it might cause me trouble later on, he said.