So what do these dogs tell us?

These are pedographs of a 12 year old male who was brought into the office last week by his mother with knee pain, bilaterally, R > L and bilateral hip pain.

Clinical findings are a left tibial and femoral leg length deficiency of over 1 cm; bilateral internal tibial torsion in excess of 40 degrees; no femoral retro or ante torsion.

Gait evaluation revealed moderate rear and midfoot pronation. He leaned to the left during stance phase on the left. Arm swing had bilateral symmetry.

So, what can you tell us about internal tibial torsion?

The tibial torsion angle is measured by looking at the angle of the tibial plateau and the intermaleolar line (see middle picture above). The distal tibia begins in utero having an angle of 0 degrees in the infant an “untwists” to 22 degrees by adulthood (see far right). Tom Michaud does a great job talking about this in this book “Human Locomotion: The conservative Management of Gait Related Disorders”. When it moves less than the requisite amount (possibly due to biomechanical. genetic or environmental influences), you get internal tibial torsion. This means the foot is pointed inward when the knee is in the coronal plane (ie facing straight forward)

External Tibial Torsion as expressed during gait.

So, last week we watched this young lad doing some static ankle and knee bends, essentially some mini squats.  Here was what we found (LINK). It is IMPERATIVE that you watch this LINK first before watching today’s video above.

Now that you have watched that link here is what you should be seeing today.

You should see that the left foot is extremely turned out. We talked about why in the linked post from last week. It is because of the degree of external tibial torsion.  When it is present the knee rides inside the foot progression line (the knee bends into the forward / sagittal plane when the ankle bends into its more lateral /coronal / frontal plane (they all mean the same thing) ie. when the foot points outwards.

Remember, the knee has only one choice of motion, to hinge forward and backward. When the knee is asked to hinge in any other direction once the foot is locked to the ground there is torque placed upon the knee joint and thus shear forces.  Menisci do not like shear forces, nor does articular joint cartilage.

So, once again we see the rule of “you cannot beat the brain” playing out. The brain took the joint with the least amount of tolerance, the knee, and gave it the easy job.  The foot was asked to entertain another plane of motion as evidenced here in this video with significant increased foot progression angle. 

When the foot progression angle is increased but the knee still must follow the forward body progression (instead of following the foot direction) the motion through the foot will be directly through the medial longitudinal foot arch.  And as seen here, over time this arch will fail and collapse. 

Essentially this lad is hinging the ankle sagittally / forward through the subtalar and midtarsal joints, instead of through the ankle mortise joint where ankle hinging normally should occur.

This is a recipe for disaster. As you can see here.  You MUST also know and see here that there is an obvious limp down onto that left limb. It appears the left limb is shorter. And with this degree of external tibial torsion and the excessive degree of foot pronation, the limb will be shorter. You need to know that internal limb spin and pronation both functionally shorten the limb length.  This fella amongst other functional things is going to need a full length sole lift. We will start with 3mm rubber infused cork to do so. And let him accomodate to that to start.

We will attempt to correct as much foot tripod (anti-pronation) control as possible to help reduce leg shortness as well as to help reduce long term damage to the foot from this excessive pronation. We will also strengthen the left gluteus medius (it was very weak) to help him engage the frontal/lateral/coronal plane better. This may bring that foot in a little. But remember, the foot cannot come in so far that it drives the knee medially. Remember who is ruling the roost here !…… the knee.  It only has one free range, the hip and foot have 3 ! 

Shawn and Ivo

External Tibial Torion: A Video showing the effects on the knee, foot and hip.

Tibial torsion is measured as the angular difference between the tibial plateau and the distal malleoli. Here we have put 2 blue dots on the tibia, one at the middle of the tibial plateau and one at the half-way bisection of the malleoli (“ankle bones”). You can see that the dots clearly do not rest on the same vertical plane, they are nowhere close in this case !  This is tibial torsion.  And since the lower dot is outside the upper dot, this is EXTERNAL TIBIAL TORSION.  It is one of the factors which determine the progression angle of the foot (see our post here).  It is easily seen here that, the foot will follow the lower dot because that is where the foot is attached to the ankle mortise joint.  This is thus what is referred to as an “increased or excessive” Foot Progression Angle.  Some will loosely, and humorously, refer to this as being “Duck Footed”.  (But we have never seen a duck with external tibial torsion so who knows how this came about ! 🙂

Normally, the angle is 0 degrees in an infant leaving the feet straight or slightly “in-toed”, and the tibia “unwinds” with growth, leaving the angle in adults at approximately 22 degrees. Angles in excess of 25 degrees are considered external tibial torsion; angles less than 15 degrees, internal tibial torsion.

In this case video it is critical to note a few things:

1- at the beginning we coached the client to straighten the feet forward so we could see the effects of the tibial torsion on the knees. In External Tibial Torsion, as in this case, the knees will always drift inwards (this is why these clients will always turn out the feet so that the knees and patella can track forward in the  normal hinge progression that is necessary for gait.  A case of external tibial torsion like this case will never see them walking with the feet straight forward (0 degree foot progression angle) because they will knock the knees together and the patella will track incorrectly and develop knee tracking pain.

2- you should be able to see that the client cannot dorsiflex the ankle sufficiently at the start because of the binding of the ankle into the torsioned distal tibia-fibula ankle mortise joint.  The client gets “locked out” and cannot squat more than a few degrees.  Be sure to notice this.  These clients should not be pigeon-holed into how they do squats and lunges (“Straighten your feed lad!” should not be your recommendation, they just won’t be able to do much if they do. They will cheat !)

3. The second set of squats show them with the feet turned out excessively. They are able to get down further now, but the knees are now tracking too far outside and not forward.  This was too much accommodation for the external tibial torsion. 

4. The 3rd set are done (at 0:28 seconds into the video) with a more reasonable foot alignment.  Reasonable for this client but far too much for someone who does NOT have external tibial torsion. You can see that the single planar hinge joint knee (the joint with the least tolerance) now moves nicely forward towards the camera.  So, they will walk with the feet at this progression angle because this is where the external tibial torsion has left the knees to rest in the sagittal (forward) plane.  Here the client will have minimal if any knee issues. However, one can only imagine what their ankles and feet and hips will think of all this !

To discern tibial torsions from femoral torsions, observe the orientation of the tibial tuberosity (the upper blue dot) with respect to the foot; in tibial torsion, there is a large difference. If this angle is withing the 15-25 degree range, then the torsion lies in the femur (femoral retro torsion and ante torsion…the subject of another post).

So, if you are training, coaching or rehabing  a client are you aware of issues like these ? Are you attempting to drive skill, endurance and strength into your clients into a lower limb plane that is reasonable for their bony alignment?  Maybe you were not even aware of these issues at all ?  Lets hope not.  You just cannot pigeon-hole all of your clients into a similar paradigm. It just isn’t that simple.  Not if you do not want to injure someone.  We get alot of these cases, sadly.

We discuss this in more detail in our Shoe Fit program that is soon to launch, but we also presented several 1 hour slide presentations on www.onlineCE.com in the recent months if you wanted to take those lectures.

Shawn and Ivo, two twisted fellas.  Torsioned dudes.  One is internally torsioned, the other external……… we cancel eachother out !

Photographs of a 6 yr. old.

What do you see ? How does the alignment look ? Are they developing normally ?
At what point should you intervene to ensure proper alignment and
development occurs in this child ? Can we standardize our visual
screen to fit all cases in all children ?  So many questions !

* this case goes very nicely with a prior case on the blog published on July 15th.

Click back and forth between the two photos above on the blog.  Youcan see that in the first photo that when the feet are parallel, the patellae point inward (normal compensation).

In photo 2, we can see that when we put the patellae in the saggittal plane (pointing
forward) the foot progression angle is severely positive (externally postured or out-toed).  

This is a severe case of FEMORAL ANTETORSION
with compensatory EXTERNAL TIBIAL TORSION.  The external tibial
torsion is an external spin along the long axis of the shaft in a
response to try to correct alignment.  You can see that in this case
there is no happy medium.  The torsion in the long bones is so extreme
that either the knees are positioned inwards when the feet are
normally aligned or the feet are spun outwards when the knees are
properly aligned.  Regardless, there is much abnormal stress on the
hip and knee joints and the labrum of the hip and menisci of the knees
not to mention the challenges into the foot mechanics and gait.

______________________________

Taking this into a gait perspective:

Patients with antetorsion are forced to externally rotate the limbs to bring the knee forward to a normal alignment from an internally rotated position.

This takes up some, occasionally all, of the lateral (external) rotation needed for the hips to function normally during gait causing compensatory rotation of the spine during single leg stance; the spine being really the only place the rotation can be achieved.

Normally, during gait the hip rotates laterally from toe off through to heel strike and is present during the initial loading response.

When this rotation does not occur in the hip, it must occur as a compensatory motion somewhere else in the kinetic chain and this is usually the pelvis or lumbar spinal joints.

Furthermore, the abnormal alignment of the femoral head in the acetabulum can repetitively irritate the hip joint and labrum let alone place abnormal torque on the tib-femoral joint (knee).

Antetorsion patients who compensate and realign the feet to a normal progression angle via tibial external torsion will force the femoral head anteriorly into the anterior hip capsule and this is a common source of pain.  It is a “hammocking effect” into the anterior capsule and it can leave the femoral head and it’s cartilage uncovered and uncompressed thus advancing arthritis degeneration. 

This is a similar symptom phenomenon as in “anterior femoral glide syndrome” as described by Shirley Sahrmann.  It is not uncommon to see a sway back lumbar posture in these clients.

These patients may have anterior contractile tissue deficits, namely stretch-weak iliopsoas as described by Kendall.

Remember to check for limb length symmetry in these clients who’s anteversion is not symmetrical. 

Watch for a future series on torsions and versions

We may be twisted, but the last time we looked, we are still …… The Gait Guys

The Case of the Apropulsive Cyborg Gait !

Can you identify the deficit in this gait pattern ?  Yes, the Cyborg looks like he is pulling his feet out of quicksand with each step, but why ?

Please do not read on until you watch the video a few times……watch the video again and improve your powers of observation and of what you know to be true biomechanically to identify the gait deficit. 

For those in the medical field, you have likely seen this problem……but only unilaterally and that is why it might  not be initially familiar. HINT: It could be a lesion of S1 (the first sacral nerve root.)

As I (Dr. Allen) sit at my computer at home I have my desk oriented so that I look out of 4  windows onto a secluded quiet street that many runners in the area have adopted as a safe road to travel. Little do they know what I do for a living let alone that I am spying on them. But, some days I feel like I should hire some high school kid to just hand out my cards at the end of my driveway with an additional little typed up synopsis of their running flaws and list of probable injuries they either currently are milking, or have in the past (or are about to experience !).  And so, on my days off I get to work at my desk and look up and see more runners run than I do during a busy day at my clinic.  It is both a blessing and a curse. It seems that I just can never get away from this stuff. Heck, I was cooking up dinner the other night and I caught a glimpse of a trailer for a new TV show, and I was hit with seeing yet another interesting gait which prompted yet another call to my partner Ivo.  I said to him, “man, you think the celebrity and Gait Guys at the Movies was a neat idea (thanks again Bill !) wait until you hear this idea ! (you will get a sample of that very idea later in the week ! It should be a hit !). Ok, enough babbling. I wanted to create enough dialogue between my initial question so that your wandering eye would not look further down for the gait deficit by curious default. 

OK, so what did you see ?

if your answer was……..the Cyborg does not have any ankle plantarflexion whatsoever, you would be right.  And without any plantarflexion a person will always be in a forward lean like they are pushing a refrigerator across the floor.  Or better yet……like a hockey player who’s skates are laced as such to block out plantarflexion. Plantar flexion, eversion and abduction are all components of pronation; the action which makes the foot a “mobile adapter” rather than the rigid lever of supination we need to propel ourselves forward.  This is why they power out the movement to the side and off the inner edge of the blade (in fact, if you look closely at the right ankle of the Cyborg, you will see it flip out into external rotation very quickly just like a NHL pro……by turning out the foot into external rotation he can thus create a push off from the medial foot and big toe, utilizing the FHL to assist in push off.

The left foot (which does not do this), has nothing else to offer. 

In this gait, the body mass must lurch forward with an abrupt jerking motion (generated by the rectus abdominus, obliques and hip flexors) and heavy forward arm pump  to accelerate the mass forward enough to literally PULL the glued foot off of the ground (PULL rather than PUSH from the gastrocsoleus/gluteal complexes). This would be classified as an APROPULSIVE gait.  We have heard some in the coaching world would call this a PULL gait rather than a PUSH gait. 

So, I wonder what this cyborg’s foot would look like ? We bet there would be a massive toe long flexor response (and likely hammer toes) in an attempt to find something in the posterior compartment for forward propulsion.  Of course this phenomenon would likely not be seen in a broad based S1 nerve root lesion but in a non-ablative non-nerve related problem (ie, a functional problem with the posterior compartment) you could see compensations such as this from the other possible ankle plantarflexor muscles (tibialis posterior, plantaris, flexor digitorum longus).  

So, good video case……..hope you enjoyed the case of the Apropulsive Cyborg !

we remain, ……. The Gait Guys……..Shawn and Ivo

A question from a doctor on the topic of limb alignment development.

The following question was forwarded to us from an internist on the USA east coast.

Question:

“I have a large number of female patients, many of them elderly.  I have noted that women in our society tend to progress to valgus knee deformity with age, and that TKR (total knee replacement) doesn’t seem to correct that deformity. Men tend more to the varus in our society.  I had formerly chalked that up to inherit gender difference.

3 or 4 years ago, I had occasion to spend a lot of time waiting outside the main Tokyo train station and observed a large number of people coming and going.  I observed the following:
1.  Young women had legs that were either straight or varus.
2.  Young women tended toward toeing in.
3.  They did all this in ridiculous high heels.
After some thought, I tend to attribute it to prolonged sitting in sesa (knees folded under), though being barefoot or in slippers while inside may also contribute.  Women in our society sit with their legs crossed.  Additionally, extensive shoe wearing leads to foot pronation.
So, could you direct me to someone who might have an interest in this observation and can refer me to any research that might have been done in this area?  I’ve had the dickens of a time trying to find anything on it, or even a specialized area of study that cares about such things.”

The GAIT GUYS RESPONSE:

Thanks for your confidence in us. Here are some thoughts:

Frontal plane deformities (or development) is twofold: genetic (and X linked) and developmental. Children usually go through a varus to straight to valgus to straight development (Ron Valmassey talks about this in his text Clinical Biomechanics of the Lower Extremities). Women generally have larger Q angles (from birth) and this angulation often causes assymetrical epiphyseal development (increased pressure on the lateral malleolus/tibial plateau stunts growth) with overgrowth of the medial femoral condyle. Developmental changes are secondary to weight (obesity causes increase in valgus angle) and posture/muscular devlopment. The increased genu valgus places weight medial to the midline (2nd met) of the foot and the foot accomodates by pronating (often excessively, as noted by both of you). This causes medial rotation of the lower leg and thigh, resulting in lengthening of the glutes (esp G max) resulting in stretch weakness and subsequent over reliance on the gastroc/soleus group for propulsion (remember this group tries to invert the heel in an attempt to cause supination once you go past midstance. Weak intrinsics (as pointed out by Dr Mark) further fuels this cycle. “W” sitting (sometimes a cultural development, as pointed out by Dr Birgit) plays in as well.

As for “toeing in”; may women have the combination of genu valgus with internal tibial torsion (often with femoral retroversion) which makes the condition difficult to treat (the rearfoot needs to be supported, but the forefoot needs to be valgus posted) otherwise the knee is placed outside the saggital plane and the meniscus becomes macerated due to conflicting biomechanics at the knee (Thus the short term fix with orthotics with a return of the pain later).

Yes, high heels and open back shoes are evil as are open backed shoes (we spoke at a convention in Chicago a few years back on this, before some of the research was out).

Thanks for allowing us to participate. below are some references for you.

-The GAIT GUYS…….Ivo and Shawn

______________________________________________________________

J Orthop Sports Phys Ther. 2008 Mar;38(3):137-49.

Differences in lower extremity anatomical and postural characteristics in males and females between maturation groups.

Shultz SJ, Nguyen AD, Schmitz RJ.

Source

Applied Neuromechanics Research Laboratory, Department of Exercise and Sport Science, University of North Carolina at Greensboro, 1408 Walker Ave., Greensboro, NC 27402, USA. sjshultz@uncg.edu

RESULTS:

When comparing maturation groups, limb length, pelvic angle, and tibial torsion increased with maturation, and anterior knee laxity, genu recurvatum, tibiofemoral angle, and foot pronation decreased with maturation. Females had greater general joint laxity, hip anteversion, and tibiofemoral angles, and shorter femur and tibial lengths than males, regardless of maturation group. Maturational changes in knee laxity and quadriceps angles were sex dependent.

CONCLUSIONS:

We observed a general change of posture with maturation that began with greater knee valgus, knee recurvatum, and foot pronation in MatGrp1, then moved toward a relative straightening and external rotation of the knee, and supination of the foot in later maturation groups. While the majority of the measures changed similarly in males and females across maturation groups, decreases in quadriceps angles and anterior knee laxity were greater in males compared to females, and females were observed to have a more inwardly rotated hip and valgus knee posture, compared to males, particularly in later maturation groups.

PMID:
18383647

[PubMed – indexed for MEDLINE]

_______________________________________________________________________

J Bone Joint Surg Br. 1995 Sep;77(5):729-32.

Development of the clinical tibiofemoral angle in normal adolescents. A study of 427 normal subjects from 10 to 16 years of age.

Cahuzac JP, Vardon D, Sales de Gauzy J.

Source

Centre Hospitalier Universitaire de Toulouse-Purpan, France.

Abstract

We measured the clinical tibiofemoral (TF) angle and the intercondylar (IC) or intermalleolar (IM) distance in 427 normal European children (212 male and 215 female) aged from 10 to 16 years. In our study, girls had a constant valgus (5.5 degrees) and displayed an IM distance of < 8 cm or an IC distance of < 4 cm. By contrast, boys had a varus evolution (4.4 degrees) during the last two years of growth and displayed an IM distance of < 4 cm or an IC distance of < 5 cm. Values above these for genu varum or genu valgum may require careful follow-up and evaluation.