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)

Podcast #18: Treadmills, ‘Shrooms & Santa

If you do not split a gut laughing by the time the band plays there is something wrong with you ! Who says gait stuff isn’t entertaining !
Perhaps our best podcast to date ? You decide.

Permalink URL

itunes link:

Topics: Treadmills, neuroreceptors, foot types, hip biomechanixcs, gait cycle

Neuroscience piece link:

1. from Eric on our FB page:

a. Had a 9yr old girl for a shoe fitting recently. She had a forefoot valgus, with a rearfoot that is neutral or slightly varus. Fairly high arch and rigid Midfoot for a child that age as well. usually a child’s foot is super flexible so this makes me wonder if it’s a compensation for a true FF varus. How do I tell if he has an anatomic FF valgus vs a compensated version?

b. I asked Blaise Dubois his opinion on Treadmill vs outdoor running and he mentioned that the literature indicates TM’s aren’t much different than outdoor. He cites (Wank 1998). To me, running feels completely different and I can’t run nearly as efficiently on a TM as outdoor. i know some people are the opposite, which i subscribe to specificity of training.

the question i have is what basis do you use for your opinion on different motor patterns? i agree with you, but the literature seems to disagree. this is a piece from cybex so of course it will be “pro-treadmill”, but they quote several studies that concur with Wank…

hope i’m not sending too many questions. i figure you can ignore them if you have too many from other listeners.
2. On the Hip Bio Pt 6 you mention ext rot leg to gain leg length.  This one has been racking my brain.  I could see how this could happen if the person supinates the foot at the same time, but is there some other external rotating mechanism occurring in the hip that would cause this lengthening?  Thanks,Ryan


Hi Gait Guys,

I am a chiropractor in South Africa, and find gait, biomechanics and running fascinating…I’m hoping to become a true gait geek one day.Reading your blog has taught me so much, you guys seem to look at gait from every angle and don’t take things at face value.

I would like to find out about your Shoe Fit Certification Program. Can people from outside the USA complete the course? Would I be able to take the exam online? and would it give me any creditation in South Africa

 Hope to hear from you soon.

 Regards, Claire

3. I have been watching your video’s on you tube.  I have a cavus foot in which I have had severe nerve pain, why is the high arch caused by nerve pain?

And would any of your exercises help with my nerve pain


4. Hi guys,
Found your youtube channel. Very interesting stuff. Have started reading up on the whole gait cycle. Its very interesting.
I have a quick question that I hope that you can help me with:
Are you aware of any correlation of hip impingement (cam/pincer) in terms of having an irregular gait cycle?
I am suffering from both CAM & PINCER impingement in my right hip. Had surgery in January, but they did not shave sufficiently off the bone, so going back to surgery soon.
I am therefore interested in seeing how surgery possible could help me with bettering my walk and strain on my lower back / leg / foot. And also in terms of looking into some theory on how to retrain myself in walking cycles.
The problem is, that this kind of rehab/research is not available here in Denmark. So would appreciate if you are aware of any research on the above, and would be able to point me in the direction of that.
Thank you – and keep those great videos coming. 🙂
Terje (Denmark)

leg length discrepancies and shoe lifts

Leg length discrepancies (LLD’s) are encountered on a daily basis. They are the root of many ankle, knee, hip and spinal problems. The questions the clinician must ask are “How much is significant?”, “How much do I add?” What are some of the signs and symptoms?” “What is the etiology?” and “How do I detect it?” A literature search (2003) provided the following information and answers.

How much is significant?

Most authorities claim that deficiencies of greater than ¼ inch (6mm) are clinically significant (1, 2) though some sources state that differences as little as 4 mm are significant (5). Subotnick (3) states that because of the threefold increase in ground reactive forces with running, lifts should be used with inequalities of greater than 1/8” inch (3mm).

How much do I add?

One of the easiest ways to determine the amount of lift needed is to examine the person in a weight bearing posture and add lifts under the short leg until the pelvis is even or until the lumbar spine is straight. If using off weight bearing measurements, you need to add 1/3 more height than measured because the talus is positioned 1/3 of the way between the calcaneus and metatarsal heads (4, 13). So, a heel lift placed under the calcaneus will only raise the talus 2/3 of that height. Lifts placed under the calcaneus can shorten the tricep surae muscles (4, 6) and apply increased pressure to the metatarsal heads (12); full length sole lifts are more physiological, though not always practical. Due to the supinatory moment of the short leg on heel strike, a lift may cause overcompensation and increased supination, with a tendency to overweight the lateral column and possibly injure the lateral ankle. Careful observation of gait post addition of a lift is in order and a valgus post running at least the length of the 5th metatarsal along with the lift should be considered (8, 9). Heel lifts also cause EMG changes of leg muscles, with decreased recruitment of gastrocnemius and tibialis anterior directly proportional to the height of the heel lift (18, 19). A lift or LLD changes the ground reactive forces associated with gait, increasing vertical force on the longer leg, along with increased joint stresses along the kinetic chain (14, 20). 

Generally speaking, lifts greater than 3/8” (9mm) require extrinsic modifications to footwear (4, 6, 8). Find a competent individual to perform this work for you. Large discrepancies should be treated gradually, at a rate of ¼ inch every 4 weeks, less if symptoms do not permit.

What are signs and symptoms associated with LLD’s?

Compensation comes in many forms, depending whether it is acute (recent injury caused an LLD or compensation resulting in one, or long term. The deficiency can cause injury on the short or long legged side (or both).

The long leg moves through a greater arc during all portions of swing phase (7). The person may flex the knee to compensate and shorten the arc. The individual may also maximally pronate and evert the calcaneus an additional 3 degrees or greater on that side in an attempt to lower the navicular to the ground and shorten that leg. This causes an increased amount of internal rotation of the tibia and thigh causing muscular dysfunction (tightness of the hip flexors, strain of the intrinsic external rotators from eccentric deceleration of the thigh), along with medial knee strain (especially with concomitant genu valgus) (4, 6, 8, 9, 10, 11, 21, 22).

The short leg side will often supinate in an attempt to lengthen and cushion some of the shock of heel strike, since it has a greater vertical distance to travel (14); this often occurs with hyperextension of that knee. This lessens the dampening ability of the knee (since it flexes almost 20 degrees between heel strike and full forefoot load), and speeds the rate of subtalar pronation (since the rear foot is inverted and still must pronate the same amount (4). Many individuals will try and attenuate impact by contracting the contralateral hip abductor muscles and eccentrically lower the shorter extremity (4, 14). This can produce excessive strain of that musculature (trochanteric bursitis) as well as pathomechanical abnormalities of the L4 and L5 motion segments (due to increased body rotation toward the short side and attachments of the iliolumbar ligaments; this can cause degenerative changes if present long term (11, 12)).

What’s the etiology?

LLD’s can be structural (anatomical) or functional (pathomechanics, compensation). LLD’s can be due to foot problems (overpronation/supination, fractures), leg or thigh problems (congenital shortening, deformity, fracture), or pelvic compensation (rotation of ilia, fractures). 

So, what is the etiology? A lot can be gleaned from the history. Past trauma is the most obvious so pay close attention. This could result in flattening of the calcaneus or overpronation due to ligamentous laxity; tibial fractures can cause shortening as well as increased or decreased tibial torsion; similar findings can occur in the femur, along with anteversion or retroversion; pelvic trauma can be more subtle and x-ray can often provide the most information (1, 2, 4, 6).

How do you determine a leg length inequality?

There are a number of methods, each with their own merit. X –ray is most accurate, but exposes the patient to ionizing radiation. Weight bearing seems most appropriate, since symptomatology usually presents itself then. Supine measurements are said to be influenced by asymmetrical muscle tension, table pressure on the innominates and hip flexor length (15). 

With the patient weight bearing and both feet placed below the trochanters, observe the level of the medial malleoli. Next, compare the heights of the tibial plateaus. Femoral length can be judged by the heights of the greater trochanters, and pelvic alignment judged by the heights of the iliac crests (4, 17).

Alternately, lay the person supine and observe the heels and medial malleoli. If there is noticeable discrepancy, they may have a short leg; if there isn’t, they still may have a discrepancy that they are compensating for. Check the range of motion of the foot and ankle in 6 general directions: plantar flexion (40-45 degrees), dorsiflexion (20-25 degrees, depending on whether the knee is flexed or extended), inversion of the forefoot (3-60 degrees, on average), and eversion of the forefoot (20-45 degrees on average), calcaneal inversion (4-20 degrees) and calcaneal eversion (4-10 degrees). Excessive calcaneal eversion usually means over pronation due to a longer leg on that side; excessive inversion can mean a long leg due to a cavus foot type (2, 4, 6, 8, 9, 12). Lack of flexibility in the posterior compartment of the calf usually causes a greater degree of pronation (16).

Now, perform Allis’s test. Bend both knees to 90 degrees and observe the height of the tibial plateaus. The lower one is usually the side of the discrepancy (which can be in tibial length or due to excessive pronation). Now walk superior to the knees and observe the femurs from more cephalad (4). Is there a discrepancy? If so, the problem may be in the femur length, femoral head angle or pelvis. Extend the knees so that the legs are lying flat on the exam table. Palpate the greater trochanters on both sides. Is one lower than the other? If so, they probably have coxa vara on the short side or coxa valga on the long side. If they are even, you need to look at the pelvis. Does one ASIS palpate more anterior or posterior than the other? This could represent compensation. A posterior or “flexed” ilia, usually causes a short leg on that side; an anterior or extended ilia usually causes a long leg on that side. Now stand the patient up and perform a Gillet Test. Have them stand erect and hold onto something for balance. Palpate the PSIS on one side along with the 2nd sacral tubercle. Have them raise their thigh to 90 degrees on the side you are palpating. The PSIS should nutate backward (flex) and drop .5-1.5 cm on the side of the raised leg. Now have them raise the opposite leg. The sacrum should nutate backward and down. If either of these movements does not occur, consider pelvic pathomechanics and treat accordingly. Recheck for motion as well as leg length when done.

Standing observation often (but not always) reveals overpronation on the long leg side and relative supination on the short leg side. The shoulder is often higher on the short side and the waistline dips to the long side because of posterior rotation of the innominate. The shoulder will dip to the side of the short leg on heel strike during dynamic evaluation (4, 6, 8, 9, 10, 11). Gait observation usually reveals adduction of the pelvis toward the stance phase leg with a lateral sway in excess of 1” during stance phase. The person will seem like they are “stepping into a hole” on the short side.


Leg length inequalities occur due to a variety of anatomical and physiological conditions. Careful analysis and examination can often reveal its etiology. To lift or not to lift is a clinical decision that is left to the clinician and patient, with a careful balance between what is perceived as improved biomechanics and tolerance levels of the patient with regards to their presenting symptomatology.


1 Cyriax J. Textbook of Orthopedic Medicine Vol I, 5th Ed. London: Baillare, Tyndall and Cassell, 1969

2 Taillard W. Lumbar Spine and Leg Length Inequality. Acta Orthop Belg 1969; 35: 601 

3 Subotnick S. Case History of unilateral short leg with athletic overuse injury. JAPA 1980; 5: 255-256

4 Micahud T. Foot Orthoses and other forms of conservative foot care. Newton, MA 114-117: 1993 

5 Martens M, Backaert M, et al. Chronic leg pain in athletes due to a recurrent compartment syndrome. Am J Sports Med 12: 148-151: 1984

6 Valmassey  R. Clinical Biomechanics of the lower extremities. Mosby, St Louis, Philadelphia. 101-107: 1996 

7 Press SJ. A report of clinical applications of computers in analysis of gait spinal imbalances. Chiro Sports Med  1987;1:30

8 Shawn Eno, personal communication

9 personal observation 

10 Botte RR: An interpretation of the pronation syndrome and foot types of patients with low back pain. JAPA 71: 243-253, 1981 

11 Friberg O: Clinical symptoms and biomechanics of lumbar spine and hip joint in leg length inequality. Spine 8: 643-651, 1983 

12 Rothenberg RJ: Rheumatic disease aspects of leg length inequality. Sem Arth Rheum  17: 196-205, 1988 

13 Travell J, Simons D. Myofascial Pain and Dysfunction: The Trigger Point Manual. Baltimore: Williams and Wilkins 112, 1983

14 Schuit D, Adrian M, Pidcoe P. Effects of heel lifts on ground reactive force patterns in subjects with structural leg length discrepancies. Phys Ther 69(8): 41-48, 1989 

15 Rothbart BA, Estabrook L. Excessive Pronation: a Major biomechanical determinant in the development of chondromalacia and pelvic lists. JMPT 5: 373-379, 1988 

16 Kirby KA Effect of Heel Height Differential in Shoes on Orthosis Function. Precision Intracast Newsletter, March 1987, 1-3 

17 Hoffmn KS, Hoffman LL. Effects of adding sacral base leveling to osteopathic manipulative treatment of back pain: A pilot study  JAOA 94 (3): 217-220, 223-226  1994 

18 Lee KH, Shieh JC, et al. Electromyographic changes of leg muscles with heel lifts in women: therapeutic implications. Arch Phys Med Rehabil 71(1): 31-3, 1990

19 Lee KH, Matteliano A, et al. Electromyographic changes of leg muscles with heel lift: therapeutic implications Arch Phys Med Rehabil 68(5 pt 1): 298-301, 1987

20 McCrory JL, White SC, Lifeso RM: Vertical ground reaction forces: objective measures of gait following hip arthroplasty Gait Posture 14(2): 104-109, 2001 

21 Blake RL, Fregeson HJ. Correlation between limb length discrepancy and assymetrical rearfoot position  JAPA  83(11): 625-33, 1993 

22 Song KM, Halliday SE, Little DG. The effect of limb length discrepancy on gait. J Bone Joint Surg 79(11): 1160-1168, 1997

More on Leg Length Discrepancies

Hi Guys,

I hope you guys are well?

I have a question I hope you can help me with?

Last week I assessed an entire football team, and over 90% have some sort of Leg Length Discrepancy (LLD). I am working with the physiotherapist to improve their weaknesses,…

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More on Leg Length Discrepancies

Hi Guys,

I hope you guys are well?

I have a question I hope you can help me with?

Last week I assessed an entire football team, and over 90% have some sort of Leg Length Discrepancy (LLD). I am working with the physiotherapist to improve their weaknesses, including using sole lifts.

My question is if it’s a tibial short leg, then a lift with align the knee and hip. But a lift in a leg with a short femur will align the pelvis but raise the knee higher than the other side. Would you still insert a sole raise, and if not, what would you do?

Kind Regards



Hi Luke

Yes, you are correct in your assumption of the change in mechanics, and yes, most often, we prescribe a sole lift, if a lift is indicated. Keep in mind that if they are asymptomatic and test out well, a lift may not be indicated. Hope that helps. You can also search LLD on the blog; we have written extensively on it:

Remember sole lifts will correct the LLD but it could shift the pelvis off further…….many LLDs are from pelvic asymmetry and core weakness, this encompasses hip rotation differences which is a typical response to the core and pelvis that is distorted. 
merely forcing a change at the Sole does not mean you are making the positive change at the top……however it may in some cases……you have to determine that with your evaluations.

Most folks legs are of symmetrical length……..the changes at the top (core / pelvis/ hip) is what throws the apparent length off.

i wish i had a good answer for your great insight……..but it is about
1- making the right changes…… that all parts are in cooperation for the restoration change
2- that you are directing change and not a further body compensattion to the compensation you have forced…….(if it is in fact a forced compensation and not the correction you are hoping for)….. time and re-evals will determine this
3- after restoration and strengthenging you must quickly wean off the lifts from them
4- you are speaking of tibial and femoral short………those are structural short LLDs , make sure you know if you are dealing with functional or structural shortness

Hope that Helps

Ivo and Shawn

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Compensations for short legs…Final installment in this series, but not our last word on this subject

We remember from from the last few weeks, there at least SIX common compensations for a short leg(week 1, week 2, week 3, week 4, week 5). Last time we looked at increased knee flexion on the long leg side. Here is the list, in case you needed a reminder:

  • hip hike on long leg side (seen as contraction of hip abductors, obliques and quadratus  lumborum on short leg side)
  • excessive knee bend on the long leg side
  •  pronation of the longer side, supination of the shorter
  • leaning to he shorter leg side
  • circumduction of the longer leg around the shorter
  • excessive ankle plantar flexion on short side

This time we will look at excessive ankle plantar flexion on short side. Normally the ankle plantar flexes about 10 degrees at initial contact/loading response, and about 20 degrees at pre swing to create “clearance”.

Watch this gentleman’s increased plantar flexion of the L calf to clear the right foot, Yes, he has an S1 nerve root lesion affecting plantar flexion of the R foot. The body needs a strategy to move around the longer leg.

Remember here is that what you are seeing is the compensation, not necessarily the problem. When one leg is shorter, something must be done to get the longer leg through swing phase.

Excessive ankle plantar flexion. Another compensation to look out for when evaluating leg length deficiencies. 

Ivo and Shawn. …still bald…still good looking…still geeky…… The Gait Guys

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YET MORE compensations for short legs…

We remember from from the last few weeks, there at least SIX common compensations for a short leg. Last week we looked at hip hiking. Here is the list, in case you needed a reminder:

  • hip hike on long leg side (seen as contraction of hip abductors, obliques and quadratus  lumborum on short leg side)
  • excessive knee bend on the long leg side
  •  pronation of the longer side, supination of the shorter
  • leaning to he shorter leg side
  • circumduction of the longer leg around the shorter
  • excessive ankle plantar flexion on short side

This time we will look at excessive knee bend on the long leg side. Normally the knee bends about 20 degrees at loading response/ midstance, and about 50 degrees during swing phase to create “clearance”.

Watch this gals R knee during swing. Yes, she has an abnormality of the R great toe extensor (torn extensor hallicus longus and brevis), but also a L short leg. It makes no difference if the leg is functionally or structurally short, the body still needs a strategy to move around the longer leg.

Remember here is that what you are seeing is the compensation, not necessarily the problem. When one leg is shorter, something must be done to get the longer leg through swing phase.

Excessive knee flexion. Yet another compensation to look out for. 

Ivo and Shawn. …still bald…still good looking…still geeky…… The Gait Guys