Adaptations and compensations.

. . . the entire system has to adapt to that deficiency. That means compensation. Now, does adding strength to that asymmetry (compensation) have a consequence. Most likely. Will it lead to injury? That is the question.

We are going to keep pounding sand on this one because we believe this is important.
All too often people are working out and strengthening their systems, and that is good. But, if they are strengthening a system that is asymmetric or strengthening a faulty pattern (clearly, as in too much arch collapse) they are likely overburdening the hierarchical system and a component of the chain of that system.
Now, many are going to argue, and we know who those folks are, they are going to argue that if the movement is not painful, if the posturing of the load is not painful, then it is not a problem. Sure, and that is easy to say, but there is no proof they are right either. And, we are not saying we are stonewalled right either, but we are trying to be logical with what we know and what some of the research says (yes, that fits our bias). But our eyes are open and we hear the arguments from the other side, but those arguments come from a crystal ball in our opinion. Truthfully, no one has that crystal ball and can see into the future to see if one side of this argument has any more "legs" to it.
However, we know that . . .

"Human movement is initiated, controlled and executed in a hierarchical system including the nervous system, muscle and tendon. If a component in the loop loses its integrity, the entire system has to adapt to that deficiency. Achilles tendon, when degenerated, exhibits lower stiffness. This local mechanical deficit may be compensated for by an alteration of motor commands from the CNS. These modulations in motor commands from the CNS may lead to altered activation of the agonist, synergist and antagonist muscles."- Chang and Kulig

So, when we see a pattern of loading that is aberrant, and especially when it is most likely playing into a client's painful presentation, it is an easier sell on the thought-arguments above. We know that the entire system has to adapt to deficiencies. It is how we are synergistically built. We have redundancies build into us that protect us. Compensation is part of the redundancy. So, does adding strength to that asymmetry (compensation) have a consequence? Most likely it does, in our opinion. Why allow an area to undergo more loading than we know it should, (ie. valgus knee loading) even if it is non-painful to a client ? Will it lead to eventual injury or pain? That is the question. But we have picked our side of the story, for now, until proven otherwise, and we work from that side of the line. For now.

"yet" is a powerful looming word.
When adding strength takes someones pain away, it doesn't mean you fixed them. It likely means you helped them adapt and protect and better negotiate the loads. However, it also does not mean that your instruction did not build a layer of initial protective strength that will not have a cost further down the road because it wasn't the right medicine for the problem.
When your cars alignment is off, and it is pulling the car to the right towards the ditch, pulling harder to the left on the steering wheel keeps the alignment aberrancy, and the ditch at bay. But nothing was fixed. You adapted and compensated. The problem is still sitting there. And you will get used to the adapted and compensated pattern of steering wheel pull in time. Until the next thing occurs. Maybe the tire will start to chirp in time, the treads silently wear unevenly, and maybe it will be your left shoulder that chirps at you, and not the car.

The squeaky wheel may get the grease, but the misaligned tire is ignored.

Shawn and Ivo, the gait guys

J Physiol. 2015 Aug 1; 593(Pt 15): 3373–3387.
Published online 2015 Jun 30. doi: 10.1113/JP270220
The neuromechanical adaptations to Achilles tendinosis
Yu-Jen Chang and Kornelia Kulig

#gait, #thegaitguys, #gaitcompensations, #gaitproblems, #compensations, #running, #walking, #genuvalgus, #pronation, #CNS, #synergist

Tibial Torsion and Genu Valgum

Join us in this brief video about tibial torsion and genu valgum in a 6-year-old

Mooney JF 3rd Lower extremity rotational and angular issues in children. Pediatr Clin North Am. 2014 Dec;61(6):1175-83. doi: 10.1016/j.pcl.2014.08.006. Epub 2014 Sep 18.

Killam PE. Orthopedic assessment of young children: developmental variations. Nurse Pract. 1989 Jul;14(7):27-30, 32-4, 36.

Kling TF Jr, Hensinger RN. Angular and torsional deformities of the lower limbs in children. Clin Orthop Relat Res. 1983 Jun;(176):136-47.

Holy Hand Grenades! What kind of shoe do I put these feet in?

Take a look at these feet. (* click on each of the photos to see the full photo, they get cropped in the viewer) Pretty bad, eh? How about a motion control shoe to help things along? NOT! OK. but WHY NOT? Let’s take a look and talk about it.

To orient you:

• top photo: full internal rotation of the Left leg
• 2nd photo: full internal rotation of the Right leg
• 3rd photo: full external rotation of the Left leg
• last photo: full external rotation of the Right leg

Yes, this gal has internal tibial torsion (yikes! what’s that? click here for a review).

Yes, it is worse on the Left side

Yes, she has a moderate genu valgus, bilaterally.

If someone has internal tibial torsion, the foot points inward when the knee is in the saggital plane (it is like a hinge). The brain will not allow us to walk this way, as we would trip, so we rotate the feet out. This moves the knee out of the saggital plane (ie. now it points outward).

What happens when we place a motion control shoe (with a generous arch and midfoot and rearfoot control) under the foot? It lifts the arch (ie it creates supination and it PREVENTS pronation). This creates EXTERNAL rotation of the leg and thigh, moving the knee EVEN FURTHER outside the saggital plane. No bueno for walking forward and bad news for the menisci.

Another point worth mentioning is the genu valgus. What happens when you pick up the arch? It forces the knee laterally, correct? It does this by externally rotating the leg. This places more pressure/compression on the medial aspect of the knee joint (particularly the medial condyle of the femur). Not a good idea if there is any degeneration present, as it will increase pain. And this is no way to let younger clients start out their life either.

So, what type of shoe would be best?

• a shoe with little to no torsional rigidity (the shoe needs to have some “give”)
• a shoe with no motion control features
• a shoe with less of a ramp delta (ie; less drop, because more drop = more supination of the foot (supination is plantarflexion, inversion and adduction)
• a shoe that matches her sox, so as not to interfere with the harmonic radiation of the colors (OK, maybe not so much…)

Sometimes giving the foot what it appears to need can wreak  havoc elsewhere. One needs to understand the whole system and understand what interventions will do to each part. Sometimes one has to compromise to a partial remedy in one area so as not to create a problem elsewhere. (Kind of like your eye-glass doctor. Rarely do they give you the full prescription you need, because the full prescription might be too much for the brain all at once.  Better to see decent and not fall over, than to see perfectly while face down in the dirt.) 

Want to know more? Consider taking the National Shoe Fit Certification Program. Email us for details: thegaitguys@gmail.com.

We are the Gait Guys, and yes, we like her sox : )

Limitations: The powers of observation will help you.

Physical examination, FMS, DNS, gait analysis … . . these are all very important tools for the coach, trainer, therapist, clinician.  They will all offer information and lead the “therapy giver” in a direction for intervention.  But when something doesn’t match up with the basic standard protocols, you have to go outside the standard box.  We have all been there and today is just a little reminder not to get caught up in the “proceedures” and merely running through protocol without an engaged brain putting the pieces together.  

Here we see 2 classic examples of deviations from the mean, the client on the left has drifted further outside the frontal plane because of tibial varum and a little genu varus.  The client on the right has imploded deep into the frontal plane via rigid pes planus foot collapse and genu valgum.  These will both affect your physical screenings for these clients. And keep in mind, and this is probably the most important point of today’s blog post, either client may have good or bad strategies around their anatomy.  In other words, some clients will have great compensations to limit further functional pathology, and some will have poor compensation strategies, and thus, both will have different physical exam findings, different screenings and different neuromotor patterns embedded deep into their CPGs (central pattern generators).   Put yet another way, all of the scenarios discussed may/will have varying screening assessment outcomes but for different reasons.  If you know the cause of these faults and the impaired neuro-recruitment patterns that are likely, your assessments will make more sense, and so will your exercise/therapy/rehab prescriptions.  If you do not understand the fundamental differences (ie long bone torsions or various femoral-neck shaft angles, foot types such as an uncompensated forefoot valgus etc) , one could prescribe therapies that will not address the underlying problems, rather they might address the compensations and strategies found with these client’s challenges.

It can get sloppy messy.  Wear a bib.

Dig for the roots, don’t mow the grass…… Shawn and Ivo, The Gait Guys

Hill Running: The Ankles Have to Get it Somewhere.

Get what ? They have to get the dorsiflexion or ankle rocker somewhere. One has to get the ankle dorsiflexion range somewhere and if it is not at the ankle mortise one can snag it from somewhere else, but at a cost.   

Remember, we need a requisite 10 degrees (preferably 15 degrees) of ankle dorsiflexion to walk and run normally (the starting reference point is 90 degrees perpendicular to the ground). You should have 30-35 degrees! (You will tap into most of this with up hill running). This motion needs to be matched with available hip extension. When one (i.e. hip extension or ankle dorsiflexion) is limited, the other is usually impaired as well.

When someone has a limitation in ankle rocker it can be found elsewhere possibly, and often, at a cost. Increased midfoot pronation is a classic strategy. If one collapses the arch enough the talus will drop forward and inwards (we know that the normal talar movement in pronation is Plantarflexion, adduction and medial rotation). These 3 combined motions will also tip the tibia forward and help to achieve the sufficient forward motion of the joint complex to allow sagittal progression of the body. The problem with this is that if the amount of pronation is too much the foot will splay compromising the foot tripod, excessive pronation will occur putting the tibialis posterior and plantar fascia at risk as well as other structures, and when this occurs the tibia will excessively internally spin dragging the knee into a valgus/medial moment thus possibly creating patellar tracking issues and significant strain on the MCL and menisci as well as other components. Increased foot progression angle, with increased forefoot pronation is another classic strategy. This option maintains the normal sagittal knee progression path, but at a cost. Many folks will attempt to mitigate biomechanical limitations when running hills by either knowingly or unknowingly turning the feet outwards. This will also allow for the increased foot pronation, internal tibial spin and valgus knee collapse BUT the turn out (increased foot progression angle) will still keep the forward/sagittal knee progression angle.  So, they are still creating all of the other pathologic compensations but fooling the knee into a forward/sagittal progression. Mind you, this is a mere smoke screen because the same detrimental foot, ankle and knee mechanics are still occuring.  The knee may be hinging forward but it is still doing so through a valgus hinge. 

In these photos we see a huge steep hill incline represented by the Merrell loop.  The inclination at foot strike is quite significant and so this represents in many ways a steep hill climb.  There are 2 photos here so be sure to click to see both. The first one (white shirt) shows just how much ankle dorsiflexion is necessary to run on this “hill” (we wonder if Merrell knows they are asking their runners to hill run at the ankle/foot level?).  It is hard to tell in the second picture but one might hallucinate that the stance foot is heavily pronating and collapsing inward.  None the less, she is still cranking out a huge ankle dorsiflexion/ankle rocker range of motion.  IF you do not have enough ankle dorsiflexion/rocker, as we discussed today, you may have to ask for it somewhere else and that could be a problem in time.

Hills and happy knees, Hills and unhappy feet, knees and hips.  It is up to you, if you are paying attention.  So many people do not.

Shawn and Ivo, The Gait Guys.  Life is an uphill struggle, manage it well and you will have happy biomechanics your golden years.

A visual demonstration of 3 different foot strike patterns. Lets test some of what you have learned here at The Gait Guys over the last few months.

On the readers left, blue shirt Bib 232:
 The left leg appears to have all joints stacked at this viewer angle (knee is vertically over the foot, hip is over the knee). What we love here is that the foot profile (look at the black sole of the shoe) is parallel to the ground, it is hard to believe that it won’t strike as such. The medial and lateral aspects of the foot should strike flush and simultaneously. This is a neutral foot and is very likely without valgus or varus forefoot typing.  The tibia looks pristine and straight without any torsion, at least from this limited perspective. He also looks to be striding nicely, it seems to appear (albeit this is reaching from this head on view) that the foot will strike below the body mass, this may be because he subtly appears to be leaning forward, again hard to see on this view.

Middle runner, white shirt:  We see some problems here.  First of all, it appears (and again, this is reaching from a front on view) that this runner is striding out with the foot beyond the body mass and will likely heel strike, he also seems to be in more backward lean that the Blue Bib Man but again hard to tell on a frontal view. We also see that the foot is pitched in inversion (note the outward tip of his foot compared to the man in Blue) quite aggressively which will facilitate a strong excessive lateral heel and/or forefoot strike pattern.  You can also see that drawing a line through the length of the long bones (tibia and femur) that they are in alignment, they are even in alignment with the 90 degree perpendicular to the forefoot inverted angulation.  This clearly represents our classic “cross over gait” which was first brought to you and the internet by yours truly a few years ago (here on Youtube link).  It is easy to see that the projected foot landing will be on a virtual line and thus appear to run on a line or even cross the feet over the line indicating that this client is not stacking the foot, knee and hips vertically and thus challenging the gluteus medius and hip stability into the frontal plane (video link here). This client will be wasting energy and efficiency in the frontal plane (side to side movement) and challenging the core, risking knee tracking issues and excessive foot pronation forces beyond the safe and normal.  

Running on the readers right, green shirt #8:  There appears to be a strong stance phase leg collapse, the hip is lateral to the foot and the knee is perhaps on its way to medial from a vertical line from the foot. This can be, and often is, from the issues of cross over described in the middle runner above but it can also be simply found in someone who is striking with the foot/knee/hip joints stacked but does not have sufficient gluteus medius strength to keep the pelvis level on the horizon (thus drift laterally). When this happens the downward collapse of the opposite side pelvis is often, but not always, see as a valgus collapse at the knee since the femur is allowed to drift medially from insufficient strength, skill or endurance pairing of the gluteus medius/maximus pairing and the medial quadriceps. This client is  likely a cross over victim as well and this would give good reason to the aforementioned.  Again, this is all theoretical from a static picture but knowing these patterns like we do, we know these typical patterns of breakdown. This is also suspect because of the foot more positioned under the midline of the body instead of under the knee and hip vertically stacked and the obvious proximity of the knees to one another.  These clients often kick or brush the foot or shoe against the stance phase lower leg as they swing the foot through. 

Who is going to win this race ? One cannot tell. But if they were the same on all levels of endurance, training, VO2 max and equal on every parameter except what was mentioned above, well then our man in Blue, # 232 would be the most efficient and likely the least injured.

Photo from an Outside Magazine article. We Would reference it, and would be happy to do so, but we cannot find the net article anywhere now. Please send it our way if you happen across it !

Shawn and Ivo, The Gait Guys … .  followed in 51 countries and counting.

A case of severe mechanical gait challenges.

This is a unique case. This is a complicated case, there is so much going on. If your eye is getting good at this gait analysis stuff you will know that just from the first pass this gait is very troubled.

This young middle distance runner who came to see us with complaints of chronic anterior and posterior shin splints. This is unusual because usually only one of the lower limb compartments are strained, either the anterior (tibialis anterior mostly) or the posterior compartment (tibialis posterior mostly). Admittedly this is not a fast runner but they love to run none the less, so you do what you can to help.

Please watch this video again and note the following:

1. crossing over of the knees at the midline (this indicates a scissored gait / circumductory motion of the limbs)
2. slightly wider based gait compared to knee postioning but neutral compared to hip spacing
3. client starts heavily on the outer edge of the feet and moves medially
4. client over strides (step length is increased) which is particularly evident when they are walking towards the camera
5. early bunion formation and troubles engaging the big toe during stance phase
6. the knees / patella also appear medially positioned in an environment of a neutral foot progression angle
7. if you look carefully you can see that they rear foot immediately moves into a valgus posturing (this is rearfoot pronation) and they are also pronating into the forefoot heavily. Interestingly they have decent arch height.

Wow ! So much going on ! This is a gait from hell in some respects. So, what is driving so much of the terrible gait mechanics ? The answer is a congenital loss of ankle rocker (dorsiflexion) bilaterally. This client can barely squat because the ankles just do not dorsiflex. There was clear osseous lock at barely 90 degrees.

Lets break each one down.

1. Crossing over of the knees at the midline (this indicates a scissored gait / circumductory motion of the limbs). * This is occuring due to some genu valgum of the knees (slightly “knock-knee”). When the knees are valgum they are at risk for brushing together during gait. The client has no choice but to circumduct the limbs to avoid this behavior. Unfortunately they cannot abduct the thighs far enough during many of the gait cycles and so a “Scissored” appearance occurs where the thighs brush and cross over in appearance.
2. Slightly wider based gait compared to knee positioning but neutral compared to hip spacing. * This is closely related to our answer in #1. Valgus knees will widen the foot spacing side to side because the feet are not under the knee joints. Then couple this with the necessity to circumduct to avoid knees from contacting and the foot posturing is that of an even wider based gait. This can also occur from many hip problems. However as in this case with a congenital loss of ankle rocker, the client uses more foot pronation to progress the tibia over the talus (allowing the tibia to get past 90degrees) and allow them to move forward. This added pronation does magnify and likely progress the knee valgum but there are few other options for this client. This is often a destructive vicious cycle with few good outcomes decades down the road.
3. Client starts heavily on the outer edge of the feet and moves medially. *This may be to avoid the immediate rear foot pronation that is seen here.
4. Client over strides (step length is increased) which is particularly evident when they are walking towards the camera. * This may be a conscious attempt to lengthen the shortened stride that occurs because of the limited ankle dorsiflexion ranges. It appears at many moments however to be a result of the extra effort to circumduct the legs sufficiently. A longer stride does play into #3 above, a larger stride usually leads to a heavier lateral heel strike but it also means that the rearfoot pronation will be more aggressive, this is a negative resultant outcome.
5. Early bunion formation and troubles engaging the big toe during stance phase. *We are not surprised here. Whenever pronation is excessive the first metatarsal (medial foot tripod) is unstable and this changes the mechanics of the hallux muscles to pull towards the 5th metatarsal anchor generating the bunion. Look at the origin and insertion of the adductor hallucis muscle particularly the transverse head, if the 1st MET is anchored the 5th MET is pulled to the 1st and the transverse arch is formed. However, if the 1st MET is unstable and the 5th is the only anchor, the adductor hallucis will pull the toe laterally and form a bunion and hallux valgus and compromise the transverse arch. (particularly look at the left big toe at the :09 to :11 second mark, the big toe and first MET are clearly not anchored to the ground).
6. The knees / patella also appear medially positioned in an environment of a neutral foot progression angle. * Answers for #1-#5 clearly will medial patellar deviation and drive patellar tracking problems.
7. If you look carefully you can see that they rear foot immediately moves into a valgus posturing (this is rearfoot pronation) and they are also pronating into the forefoot heavily. Interestingly they have decent arch height, but remember, that does not mean that pronation is not occurring. * This is a result of the loss of ankle rocker mechanics. If they start pronation early at the rear foot it will drive more pronation. When pronation is driven excessively the arch can drop, and with more arch height drop the tibial will pitch forward past the magical 90 degree mark and allow forward motion to occur.

So, how can they run with all this going on ? Well, the answer is quite simple. They avoid most of these issues as best they can. How you ask ? Forefoot strike; they run avoiding heel strike and midfoot strike. By staying on the forefoot all of these rear and midfoot mechanical limitations as well as ankle rocker loss can be avoided by remaining on the forefoot. This makes distance running difficult but anything below the two mile mark is tolerable and the 100-800 distances are probably best suited for their feet. Incidentally they enjoy the 400 the best, no wonder. Also, moving at increased speed will necessitate a forward lean, and a forward lean makes the tibia progression over the talus easier taking out some of the ankle rocker limitations.

This is a foot type, with complications, that is really beyond much of what anyone can do conservatively. We would even argue that surgery is not an option, just a change in activity choice. This is simply a client that should not run beyond distances where they can stay on the forefoot. The foot, ankle and lower limb mechanics just suffer far to much from having to compensate (as discussed in #1-7) to enable pain and problem free running with anything other than forefoot loading. This means that walking is going to be difficult and problematic, as you can see from this video above.

Our only solution in this case ? ……… utilizing a rocker based footwear. Easy Spirit Get UP and Go (link) was our recommendation and it worked very well for this client for walking. Here is a link to this shoe and pictures of the huge forefoot rocker that helps (somewhat) to dampen the mid-forefoot rocker issues but there is not much that can be done for the rear foot rocker issues as discussed. If you use an orthotic to block the rearfoot valgus motion and rearfoot pronation you will pass more challenges to the midfoot-arch and forefoot. Sadly.

This was a very tough case. Getting every aspect of the case in your head during an evaluation is sometimes a challenge. Sometimes you need to see them a 2nd or 3rd time to digest it all. But be patient with yourself, it takes time to get decent at this stuff. This is a perfect case for “getting a feeling and flow” of the persons gait, at their speed. A case evaluation like this on a treadmill or via video analysis can make things tougher because the treadmill can change the dynamics (did you read our Treadmill article in last months Triathlete magazine ? It was linked on the blog 2 weeks ago) and make the client move at its speed and not their speed inhibiting and promoting different mechanics. There are times for a treadmill and times to avoid them. This is an art, in time you will know when to use and when not to use.

Happy Monday Gait Gang………. welcome to The Gaits of Hell !

Shawn and Ivo ……….two gnarly lookin dudes with pitchforks and a toothy grin.

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.