Getting your knee to work properly is a complicated, multi-faceted operation. Staying injury-free (or recovering from injury) takes ankle flexibility, hip control, quadriceps strength, hamstring strength and flexibility, good posture, and other aspects just to name a few. However, in my experience, there tends to be one muscle that seems to me more important than the rest. . . .
The popliteus is an extremely important muscle in the back of the knee. It's main purpose is the "unlock" the knee. Meaning it's the first muscle that takes part in the initiation of bending the knee from a straight or locked position. Now, what make the popliteus matter more for the knee pain population is that some of the fibers of the popliteus actually intertwine with the meniscus. The meniscus is a cartilage pancake in the middle of the knee that very commonly becomes fixated, torn, and injured. Many times those meniscus injuries are a direct result of poor function of the popliteus. After checking the orthopedic integrity of a knee (to check if there are torn ligaments), the next most important step in examining a knee is to evaluate the quality and function of the popliteus.
Treatment of the Popliteus
The most effective treatment for the popliteus that I've seen is the Active Release Technique (ART) popliteus release. This can be performed by ART certified manual therapists such as chiropractors (like myself), physical therapists, licensed massage therapists, etc. There are many non-ART manual therapy releases for the muscle as well. Manual therapists can treat any adhesion or scar tissue in the muscle that might be limiting it's function and effectiveness. The therapist can also help when the popliteus is adhered to a hamstring muscle or the meniscus itself. If you're dealing with knee pain in the front or back of the knee, I recommend getting your popliteus released before more aggressive actions like injections or surgery.
Kinesiotape for the Popliteus
Kinesiotape is a big help for improving the function of the popliteus. Kinesiotape is a stretchy tape that, when applied correctly, will decrease the pressure in the blood vessels that impact the popliteus allowing for increased blood flow to the area. The more blood flow, the quicker you heal and the better you feel. So consider using kinesiotape. Just be sure to shave or trim any excess hair in the area. This doesn't feel good on a hairy leg!
Self-Release of the Popliteus
Now, the first thing to note is that lacrosse ball and self release of the popliteus is not as effective as professional treatment to the area. However, they do provide some value and people are going to do this anyways so I might as well give some tips on how to do it correctly.
There are sensitive structures behind the knee--the popliteal vein, artery, and nerve are in the area. So don't be overly aggressive when releasing the area as damage to those structures can lead to problems far worse than knee pain.
If at any time you feel numbness or sharp pin-point pain, move the lacrosse ball to another location--half an inch to the left or right and you should be fine. Hold for 30 or 40 seconds only. This is not something to do for more than a minute.
Popliteus Activation Exercise
This is a Tibial Internal Rotation Activation Technique by Dr. Brent Brookbush, a very respected authority on rehabilitation and fitness education. The video is a little long and complicated but if you're able to stick it out, it's a great activation exercise for performing directly after the popliteus lacrosse ball self-release. The release and activation should be performed before activity, as opposed to after.
Finally, we're ready to start performing real exercises now. I'd start with the Chop and Lift exercise. It's a great way to start incorporating full body movement, while still being able to concentrate on proper posture and positioning of the knee. Perform this exercise and DO NOT let the knee shift towards the midline of the body. One set of 10 reps on each side should be enough to prepare you for your more fitness-based exercises (squat, lunch, deadlifts, etc). Make sure only to advance the exercises if you're knee is pain free during each movement.
Good luck! Please leave a comment below to let me know if this article is helpful for you.