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Injuries and Medical Advice

Knee Pop

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I felt a sharp pain and heard a popping noise while doing a drop knee a week ago. My knee wasn’t sore at the time but hurt the following day, mostly on the inside surface of my knee. I am worried about my ACL. Should I get an MRI?

—Albert Boenardi


Your ACL is fine. If it was otherwise I doubt you would be asking me. Rather, you would be seeking medical advice more concomitant with your injury presentation. Something like, “AAAHHHH, my knee my knee my knee! Please, someone, take me to the hospital.”

More probable is that you have partially torn your MCL (medial collateral ligament). Typically it starts with a slightly alarming pop (as opposed to a cataclysmic one), whereby you wonder if you have injured yourself, promptly followed by the decision that you haven’t because, in the absence of much pain, that is the straw you want to grasp. After an hour or so you will still be clinging to that straw albeit with diminishing hope. Pain will wake you that night every time you roll over or your knees touch each other. By morning you will be dabbing away the tears of reality.

Forget the brace unless you want to grasp at more delusional straws. There is nothing to do other than allow it to heal. In three weeks it will be 90 percent better. In two weeks you will question that prognosis, but the improvement in the third week is often quite remarkable.

Unless you have other immediate symptoms besides some medial surface tenderness, like locking of the knee, or a sense of it giving way beneath you, I wouldn’t bother with an MRI. If there is still considerable pain after a month, an MRI is a good idea.


There are four major ligaments in the knee, but the anterior cruciate ligament (ACL) is the one most at risk while climbing. The posterior cruciate ligament (PCL) is rarely damaged other than when you fall onto the ground.

There are also two cartilage discs (menisci) within the knee that afford the knee some shock absorbency and enhanced stability. Tearing either one of these is fairly common in climbing.

Snapping or popping noises around a loaded knee typically indicate a ligament giving way. Often there is little pain initially, and most people, denial in full bloom, will hope “it was just the joint cracking.”


Tearing of muscles and tendons is usually a sensation rather than a noise, unless the tendon fully ruptures. An Achilles tendon giving way can sound more like a gunshot!

Meniscal tears are usually very quiet, but the wide-eyed face of instant anxiety is a dead giveaway.

A knee that locks during extension, or feels unstable, needs to be assessed by someone qualified.

Pain is not a good indicator of damage. Ligaments that are completely ruptured often produce only mild pain.

Feature image by Bjorn Pohl

This article appeared in Rock and Ice 246

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