Exploring the Links Between Human Movement, Biomechanics & Gait
Why does this gal have so much limited external rotation of her legs?
We have discussed torsions and versions here on the blog many times before. We rarely see femoral antetorsion. She came in to see us with the pain following a total hip replacement on the right.
Note that she has fairly good internal rotation of the hips bilaterally but limited external rotation. This is usually not the case, as most folks lose internal rotation. We need 4 to 6° internal and external rotation to walk normally. This poor gal has very little external rotation available to her.
Have you figured out what’s going on with hips yet? She has a condition called femoral ante torsion. This means that the angle of the femoral neck is in excess of 12°. This will allow her to have a lot of internal rotation but very little external rotation. She will need to either “create” or “borrow” her requisite external rotation from somewhere. In this case she decreases her progression of gait (intoed), and borrows the remainder from her lumbar spine.
So what do we do? We attempt to create more external rotation. We are accomplishing this with exercises that emphasize external rotation, acupuncture/needling of the hip capsule and musculature which would promote external rotation (posterior fibers of gluteus medius, gluteus maximus, vastus medialis, biceps femoris). A few degrees can go a very long way as they have in this patient.
confused? Did you miss our awesome post on femoral torsions: click here to learn more.
Wow! Can you figure out why this person at the distal end of her first metatarsal under her medial sesamoid.
She recently underwent surgery for a broken fibula (distal with plate fixation) and microfracrure of the medial malleolus. You are looking at her full range of dorsiflexion which is improved from approximately 20° plantarflexion. She is now at just under 5°.
She has just begun weight-bearing and developed pain over the medial sesamoid.
The three rockers, depicted above from Thomas Michauds book, or necessary for normal gait. This patient clearly has a loss of ankle rocker. Because of this loss her foot will cantilever forward and put pressure on the head of the first metatarsal. This is resulting in excessive forefoot rocker. Her other option would have been to pronate through the midfoot. Hers is relatively rigid so, as Dr. Allen likes to say, the “buck was passed to the next joint. ”
There needs to be harmony in the foot in that includes each rocker working independently and with in its normal range. Ankle rocker should be at least 10° with 15° been preferable and for footlocker at least 50° with 65 been preferable.
If you need to know more about rockers, click here.
A visual example of the consequences of a leg length discrepancy.
This patient has an anatomical (femoral) discrepancy between three and 5 mm. She has occasional lower back discomfort and also describes being very “aware” of her second and third metatarsals on the left foot during running.
You can clearly see the difference in where patterns on her flip-flops. Note how much more in varus wear on the left side compared to the right. This is most likely in compensation for an increased supination moment on that side. She is constantly trying to lengthen her left side by anteriorly rotated pelvis on that side and supinating her foot and trying to “short” the right side by rotating the pelvis posteriorly and pronating the foot.
With the pelvic rotation present described above (which is what we found in the exam) you can see how she has intermittent low back pain. Combine this with the fact that she runs a daycare and is extremely right-handed and you can see part of the problem.
Leg length discrepancies become clinically important when they resulting in a compensation pattern that no longer works for the patient. Be on the lookout for differences and wear patterns from side to side.
One point and 1 treatment can profoundly influence gait
When talking about the lower extremity and gait (as I have been know to do at more that one seminar), I often talk about the “reverse engineering” principle. This is looking at a muscle or muscle group from a “ground up” perspective, as it would be functioning during the gait cycle. This, along with knowing when a muscle should be firing in the gait cycle, can provide clues to what may be going on and how you may be able to help.
When discussing the quads, we often employ this principle. It can be a little difficult to think of the vastus medialis as a lateral rotator of the thigh and the rectus femoris as a flexor (anterior nutator) of the pelvis, but if you put your foot on the ground and think about it, you will see what I mean.
The VMO is often implicated in patello femoral syndromes but cannot be selectively activated. The ratio between vastus medialis and vastus lateralis does seem to be alterable and perhaps is a siginificant factor.
How about if we look at the vastus lateralis instead?
The vastus lateralis is the largest and most powerful portion of the quadriceps. One paper reports that the muscle volume of the the vastus lateralis was 674 cm3 followed by the vastus intermedius at 580 cm3, vastus medialis 461 cm3 and lowest in the rectus femoris 339 cm3. This makes the vastus lateralis is twice the volume of the rectus femoris!
Studies of muscle fiber orientation show that VL force component is directed approximately 12-15° laterally with respect to the longitudinal axis of the femoral shaft. This would mean it has a tremendous mechanical advantage and could (should?) pull the patella directly laterally compared to the VMO force, whose component is directed approximately 55 ° medially. The muscle “balance” between the VMO and the VL, along with the periarticular soft tissue structures acting on the patella, is considered major component in the control of normal patellar alignment and function. The VL is often considered to be the “overactive” one by many clinicians, particularly in cases of patellofemoral dysfunction. It turns out that from an EMG standpoint, they may be correct.
The vastus lateralis arises posteriorly from the femur along the linea aspera and circumnavigates the thigh in a counterclockwise fashion to attach laterally to the patellar tendon. Because of its size and fiber orientation, it would stand to reason that needling it would have more cortical representation than say the vastus medialis.
There is an interesting paper where they needled a single acupuncture point: Stomach 34. For those who haven’t studied acupuncture (or don’t remember) this point is located on the thigh, in a small depression about 2.5 inches (63 mm for the metric folks) lateral to and above lateral border of the patella. In other words, it is in the vastus lateralis (see above).
The results showed statistically significant improvement in velocity, cadence, stride length, cycle time, step time and single/double leg support after treatment. The effect was small, but positive.
Think about where the trigger points are for this muscle (see above) ; fairly close to this point, sometimes (depending on the trigger point), even directly over this point. Needling has many effects on muscle and its trigger points and we like to think that needling “normalizes” function of a muscle; perhaps it influences the apparent “dominance” of this muscle and allows the patella to track more medially?
So, in this popultion of patients of elderly individuals, 1 acupuncture (needling) treatment had a positive influence on their gait. Perhaps if the folks in the knee study were treated a few more times, we would have seen a change. Imagine what could have happened if aditional treatment modalities, like exercise, proprioceptive work and gait retraining were added!
What a great, cost effective alternative or addition to your rehabilitation this could be. Consider adding this modality (and point!) to your current clinical toolbox, not only for older patients but for any patients that may have a gait abnormality.
Kim, H. H., & Song, C. H. (2010). Effects of knee and foot position on EMGactivity and ratio of the vastus medialis oblique and vastus lateralis during squatexercise. Journal of Muscle and Joint Health, 17(2), 142-150.
Lam, P. L., & Ng, G. Y. (2001). Activation of the quadriceps muscle during semisquatting with different hip and knee positions in patients with anterior knee pain. American Journal of Physical Medicine & Rehabilitation, 80(11), 804-808.
Erskine, R. M., Jones, D. A., Maganaris, C. N., & Degens, H. (2009). In vivo specific tension of the human quadriceps muscle. European journal of applied physiology, 106(6), 827-838. [PubMed]
Grabiner MD: Current Issues in Biomechanics (9th ed). Champaign, Human Kinetics Publishers, 1993.
A clear cut case of Form follows Function. Leave a deforming force long enough and the body will accommodate.
When the lateral quadratus plantae (QP) is weak and the flexor digitorum longus pulls unopposed (relying on the QP to properly orient the long flexor pull) for too long the 4th and 5th toes and drift medially and spin inwards toward the midline of the foot (as seen in the photo). Then, as the 4th toe presses down on the fleshy pad of the 5th toe, over time the fleshy pad is pancaked and triangulated. Then, with repeated pressure a corn like hardness becomes of the tip of that triangluted tissue, it resembles a hard callus. A corn is a coalescing of the skin cells into a tighter formation, a reaction to fend off repeated pressure and friction. Form follows prolonged function. Shave these things down and they will come back, unless you get to the root source of the problem, which could be all the way up the chain.
These pix come to us from one of our brethren, Dr Scott Tesoro in Carbondale of a 73 yr old golfer with mild LBP and a L knee replacement three yrs ago. He has a VERY short R leg (close to an inch).
What you are seeing is he ultimate compensation for a short leg. Note how he takes the shorter side and supinates it (to the max!). You can see the external rotation of the lower leg and thigh to go along with it. If you look carefully and extrapolate how his left leg would look “neutral”, you can see he has internal tibial torsion on this (right) side as well. He has some increased midfoot pronation on the right compared to the left, but not an excessive amount.
A full length sole lift would probably be in order, as well as potentially addressing some of his compensations. Wow, what a great set of pictures !