I tore some ligaments
in my left knee while skiing in the backcountry last Sunday.
Sherman Alexie wrote a short story about two brothers who went to a party, started fighting, and beat themselves unconscious (Every Little Hurricane, 1993). The brothers were the protagonist’s uncles and the whole story played out again at another party and then another. The uncles spent their whole lives with an unspoken agreement to be each other’s weapons of self-destruction.
Homer, the ancient Greek, told of Odysseus and his soldiers who came upon the singing of bird women (Sirens) so beautiful that they couldn’t stop themselves from diving into a violent sea and crashing into the rocks. Only love and beauty mattered when faced with a siren song; logic be damned. Odysseus blocked the ears of his men with wax so they would not hear the Sirens and continue and fight the people of Troy. For his part, Odysseus wanted to hear the Siren song so badly that he had his men tie him to the mast so he could not escape but still listen. It drove Odysseus mad, at least temporarily.
Odysseus and the Sirens. Greek vase (ca. 480 BCE). British Museum. The Sirens were not mermaids but beautiful women with wings.
But you see, I am a scientist… a biologist. Logic says there is no evolutionary gain for two brothers to beat each other senseless at every local party. There is no evolutionary gain to jump into a violent sea for a Siren’s song either. Love and logic are like that. The uncles will fight each other until one of them is dead and yet they love each other.
Logic and physics say you could get maimed or killed flying down a mountain on a pair of skis. It’s simple physics. Force equals mass times acceleration. Mass is measured in kilograms and in this case acceleration comes from gravity is 10 meters per sec2. There is also upward acceleration exerted by your jump. Force calculates to kilograms times meters divided by the number of seconds squared (kg(m)/sec2 ) but that is a mouthful so physicists call the unit of force a Newton. After Isaac. It’s a more complex physics equation that determines the force that exerted on your knees because there is torque involved but the units of force are still Newtons. I won’t bore you (or excite you) with calculus except to say that torque increases the force on your knees when you’re doing a hop turn. An even more complex equation the force one exerts on the tendons in your fingers when you crimp in rock climbing. So far the tensile strength of my hand tendons are holding the stress of climbing rocks.
Isaac Newton’s equation for force.
A hop turn is just what it sounds like. It’s a turn while hopping and twisting on skis. You initiate a turn which drives your skis deeper into the snow and you hop out of the snow, twist, and finally land pointed a different direction. All of this happens in about a second. A hop turn compresses your knees at first, a microsecond later pulls the bones in your calves apart from the bones in your thighs, and finally compresses the cartilage in your knees again when you land in the new direction. Throughout the turn your knee cartilage is being twisted apart and your ligaments and tendons hold it together. It’s a tug of war between the force of the jump and the tensile strength of the cartilage. Keep your cartilage healthy. It’s a public service announcement.
Up to a point, the human knee evolved to take this sort of abuse but apparently I past that point last Sunday and felt a pop in my knee. Lots of people do all sorts of things that could break a human to pieces and most of the time we come out okay. The pop happens when the force exerted on the knee exceeds the tensile strength of the ligaments. It hurts when a ligament tears but the real pain is the immediate understanding that there is a long road of recovery coming. In the case of my injury, I initiated a hop turn slow my descent and to miss a tree but it’s more complicated than that.
I am in love with hop turns. I didn’t have to ski the steep slope through the trees but then again, I had winged women singing in my ears and the lyrics were, “Don’t ski the groomers. Those are for pansies.”
High East Bowl, Douglas Island.
It isn’t only hop turns or even skiing enticing me to jump into a violent sea and die pursuing sirens. My knee has been sore pretty much constantly since July when I slipped and twisted my knee while running a mountain ridge. Apparently I am polyamorous because I love trail running, rafting whitewater, and climbing rocks as well. A week or I twisted my knee in July I was back running again and did it again and then again and again. I have twisted this same knee before doing similar stuff. Perhaps I should strap myself to the mast like Odysseus.
Blackerby Ridge 2020. One of my favorite trails runs.
How does a scientist like me deal with sirens? I am supposed to be logical. I am supposed to follow the facts and the facts say my knee loves me and wants me to love it back. My body doesn’t want me to treat it like those uncles in Sherman Alexie’s short story. They loved each other. They hated themselves. The story of the sirens in the Odyssey has stood for two thousand years because people have been throwing themselves into the sea (metaphorically) since the first Neanderthal decided to hunt a mammoth with a spear. The risk didn’t make sense but there was a mammoth and that Neanderthal was a hunter. Sometimes you have to prove to yourself that you can. The siren song is anything that erases logic. Then again, most of Odysseus men were killed in battle a few days later. Now that I think about it, it’s much more gallant to die trying to score with a woman with wings than get stabbed and bleed to death at war.
Unless I don’t heal as expected, I won’t need surgery for this tear. My goal is to be kind to my knee, work on physical therapy, and spend more time playing the guitar. I wrote a song about the Sirens a few years ago. Music is yet another love. Listen to it if you want.
Sirens, the song
