Muscles and Knee Pain
Tests and Treatment for Rectus Femoris (Quadriceps)
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A complete list of tests and treatments will be available in the
upcoming book Surviving Martial Arts.
Knee Pain Due to the Rectus Femoris Muscle
Pain in the front and center of the knee, particularly when
walking downstairs or downhill, or when wearing
high heels. Difficulty extending the hip or fully flexing the knee.
There are also leg locks and pins
that specifically take advantage of tight quads.
(Note: The vastus intermedius
muscle, lies beneath the rectus femoris. This "forgotten quadricep"
tends to cause more problems walking upstairs or up hill
and refers pain to the
upper thigh. When tight, these two muscles together can cause
the hip to buckle when you straighten your knee and step back.)
About the Muscle. This common problem
originates in the rectus
femoris muscle in the front of the thigh. The rectus femoris
(one of the quadriceps muscles)
runs from the front edge of the pelvis down to the front of the shin,
just below the knee. (The "X" in the picture indicates the most
likely trigger point, but notice that the pain is concentrated on and
just above the knee, far from where the pain actually originates.)
When this muscle is tight and shortened
by trigger points (areas where fibers are
abnormally shortened) it tends to pull the pelvis forward, creating a "sway back," an anterior
(forward) rotation of the pelvis. It also forces the knees back into
hyper-extension, causing strain on the cruciate ligaments of the knee
as well as other muscles and connective tissues.
The sway back or "bubble-butt" figure is
very commonly seen in female gymnasts and ballerinas, in soccer players
and others who develop powerful thigh muscles especially in those
who conscientiously stretch out their hamstrings.
Think of the pelvis as a pulley. The quads pull down on it from the front.
The hamstrings pull down on it from the back. Ideally there is a balance between
the two muscle groups. But . . . when rectus femoris is tight it will rotate the
pelvis forward. Simply stretching out the hamstrings alone will increase
any problems with anterior pelvic tilt. To avoid this, rectus femoris must also be stretched.
Unfortunately, because the rectus femoris crosses two
joints (hip and knee), it is rarely stretched out fully.
Testing for Rectus Femoris Problems
Test 1: The Swayback Test
A quick test for a tight rectus femoris is the
Lie on your back on a
firm surface with your legs straight. Relax. Imagine for a moment
that you are lying in warm sand at the beach.
Is there room to slide a hand? - an arm? - between back and sand?
While there may be a little space, too much space,
such as space for a hand, or (worse) a whole arm, is not good. The
more space beneath the small of the back, the more likely that there
is anterior rotation of the pelvis, hence problems with the rectus
Test 2: Heel-To-Butt Test
To test for tight rectus femoris, with help from a
- Lie on the side of table or bed with hip and knee hanging
slightly over the edge. (Flex the other knee as shown to protect your
- Have your partner bring your heel slowly and
gently toward the same-side buttock. Ideally heel should touch
buttock, but do not force it; move the heel only until resistance is
felt. The farther the heel from the buttock, the tighter
the rectus femoris muscle. If you are short by a couple feet and have
kneecap pain with no apparent structural damage, you may have found the reason.
If you fail this test and are in wrestling, Brazilian Jiu-Jutsu,
mixed martial arts, or other styles with ground techniques, you
will be extremely vulnerable to
Fortunately this is one of the easiest muscles in which to produce
A rectus femoris with decreased range of motion probably contains trigger points. To self-treat this muscle:
1. Sit in a chair.
2. Place same-side elbow a few inches above the middle of your
3. Gently press into the muscle at various points from the knee up to
the attachment point on the pelvis. Trigger points are most commonly found
in the upper portion near the hip.
Note that trigger points always hurt when pressed, but not everything
that hurts is a trigger point. Feel for distinct areas of swellings or
nodules. These areas may range in size from a pea to a walnut.
4. Hold gentle pressure on the tender area until the pain subsides.
Notice in the pain pattern diagram that the
main trigger point is just below the muscle attachment near the
hip. For that point, it is easiest to have a partner apply
pressure. Or, to self-treat, you can place a tennis ball on the
floor or wall and lie or lean against the point. Remember, gentle (but firm) pressure is best!
After pressure treatment, the muscle must
Once you have treated the muscle, stretching should be done at least
once every (waking) hour for several days. Stretching should
not hurt. Do each stretch 3 times, holding each one for
3-5 seconds. Always treat and stretch the muscles on both sides.
- Repeat the range-of-motion test, pulling heel toward the same-side buttock. (Don't twist the knee.)
- Repeat, pulling heel towards the opposite buttock.
Remember, the hip must be straight or extended back. If the hip is flexed (as is
so commonly done), you are stretching the vastus muscles only, not the rectus femoris.