A look at some common knee injuries.... And why Dr. Dave got into the medical field.

A knee injury is what got me into medicine. It was 2003 or 2004, and I was up skiing at White Pass, Washington with my family, and a close family friend and physician, Dr. Shawn J. Aaron, MD.  

By 15 years old, I had expressed some interest in medical terminology and various medical factoids, but not chosen medicine as a potential life path as yet. Dr. Shawn was skiing behind me, as I took a turn into some trees. A couple sharp turns at speed later,  I stopped, and ended up waiting for some time for him to exit the woods. Concerned, I hiked back in to where I thought he might be, and found him sprawled out, one ski ejected, clutching his knee.  

We limped to the bottom of the mountain, and into the lot, where the truck was parked. The next few minutes were life-changing for me. Dr. Aaron proceeded to instruct me through the various diagnostic orthopedics to detect the damaged structures in his injured knee.  

There, at 15 years of age, in the bed of a Ford pickup, I helped to diagnose a medial collateral ligament and medial meniscus tear.

Now, living in Bozeman, I get to use these skills just about every day, assessing patients who like to live life on the edge.  

Knee injuries are prevalent in court, field, and winter sports. Contact and non-contact injuries alike can wreak havoc on a good healthy knee. There are several things that can cause pain and dysfunction in the knees. In this article, we'll explore some basic anatomy, and look at three of the most common knee injuries, and how they are often addressed.

In orthopedics the injuries caused by a blow to the lateral side of the knee is referred to as the “unhappy triad”. The three structures referred to here are: medial collateral ligament, ACL, and medial meniscus.  


  • The Anterior Cruciate Ligament is a structure that attaches between the two “knuckles” at the end of the femur 0666650001554225684.jpg(thigh bone), and to the top of the tibia (shin bone). There is an ACL and also a PCL, or posterior cruciate ligament, which cross each other to provide front to back stability for the knee. These ligaments keep the femur from sliding forward or backward on the tibia, for activities such as going up and down stairs, or starting and stopping quickly during sports.

  • These structures are most commonly injured during pivoting with a planted foot, or with a blow to the lateral side of the knee, when the athlete has a foot planted.

  • ACL tears create pain and often severe swelling in the knee, as well as instability that prevents the athlete from descending stairs or pivoting without instability or shifting of the knee.

  • Complete tears typically do not heal without surgical reconstruction.  

  • One interesting article stated that in some cases, early intervention with rehab can help the knee regain full function without surgery. The study also mentions that delaying surgery in order to attempt more conservative measures first, does not seem to negatively affect the overall outcome.    

  • Frobell, R.B. New England Journal of Medicine, July 22, 2010; vol 363: pp 331-342.

  • Healing time: 6-8 months


  • This is the structure that holds the medial (inside, between the knees) portion of the femur to the medial portion of the tibia.  0747158001554225703.jpg

  • commonly injured with blows to the outside of the knee, or forcefully falling onto the inside of the knee, common with goalies in hockey.

  • Sometimes reconstructed, especially if injured with the ACL and meniscus

  • Healing time: 1-6 months



  • these are cup-like cartilage cushions, which hold the joint surface of the femur (thighbone) against the tibia (shin bone).  

  • Commonly torn with a twisting fall with a planted foot, or a foot in a ski binding which does not release, or blows to the lateral side of the knee.  

  • can cause locking with knee bent if a “bucket-handle” tear  0971887001554225768.jpg

  • meniscectomy (partial or complete removal of this cartilage) is sometimes undertaken, or sometimes reconstructed.

  • healing time: 2 weeks-6 months  


  • Knee injury is often seen as activity, season, or career ending, but it doesn't have to be. With proper care and rehabilitation, athletes and weekend warriors alike can return to their activities.  

  • Your best bet after a knee injury is to be examined by a healthcare practitioner who is familiar in orthopedic diagnostic procedures. A simple examination can often uncover the source of trouble without need for imaging. Sometimes, imaging is needed to determine the injured tissues, and subsequent referral for surgical or rehabilitative care can be made.  

  • As with any healthcare need or problem, work closely with your healthcare provider to maximize your benefit from treatment. Work with a provider who clearly understands your goals, or will help you set realistic goals for return to activity.  


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