The amazing power of compensation. Coming to a patient in your office… Maybe today

This gal has had a right sided knee replacement. She has an anatomical right short leg, a forefoot supinatus, an increased Q angle and a forefoot adductus. So, what’s the backstory?

When we have an anatomical short leg, we will often have a tendency to try to “lengthen“ that extremity and “shorten” the longer extremity. This is often accomplished through pelvic rotation although sometimes can be with knee flexion/extension or change in the Q angle. When the condition is long-standing, the body will often compensate in other ways, such as what we are seeing here.


The fore foot can supinate in an attempt to lenthen the extremity. Note how the right extremity forefoot is in varus with respect to the rearfoot, effectively lengthening the extremity. As you can see from the picture, this is becoming a “hard“ deformity resulting in a forefoot varus.


Over time, the forefoot has actually “adducted “ as you can see, again in an attempt to lengthen the extremity. Remember that supination is plantar flexion, abduction and inversion, all three which are visible here.

You will also see that the Q angle is less on the right side (se above), effectively lengthening that extremity, but not quite enough as we can see from the picture :-)

Dr Ivo Waerlop, one of The Gait Guys

#forefootadductus #shortleg #kneereplacement #tkr #forefootvarus #gait #thegaitguys

Knee braces and long legs?

Knee brace fixed at a zero to 5 degree flexion angle, creating a long leg? 

We know that the knee is supposed to flex during stance phase, usually around 20-25 degrees (depending on speed and weight, increases in bot increases the flexion requirement) to create dampening from vertical oscillation of the pelvis. What happens if they cannot flex? This creates a virtual "long leg" on that side this will usually result in:

  • Increased vertical translation of the pelvis upward on the braced side and

  • A compensation to make up for this "long leg; circumduction in this case,  but it could be any of the other compensations that we have talked about in posts here on the blog. 

work arounds? They are tough as each can create their own set of problems

  • allow more flexion in the knee on the braced side (not always possible)

  • place a full length sole lift on the opposite side to make up for the difference

  • use crutches

  • use a skateboard : )

we are sure you have some as well that you would LOVE to share with us

Dr Ivo Waerlop, one of The Gait Guys

#shortleg #LLD #compensations #legbrace #gaitproblem #thegaitguys


K ShamaeiGS SawickiAM Dollar Estimation of quasi-stiffness and propulsive work of the human ankle in the stance phase of walking - PloS one, 2013 -

MORAIS FILHO, Mauro César; REIS, Renata Albertin dos  and  KAWAMURA, Cátia Myuki.Evaluation of ankle and knee movement pattern during maturation of normal gait. Acta ortop. bras. [online]. 2010, vol.18, n.1 [cited  2019-04-25], pp.23-25.

Wild Haggis? Leg length discrepancies on the uphill side? What?

An old Scottish myth has it that the wild haggis (given the fitting taxonomic moniker Haggis scoticus ) is a small fictitious creature (although many folks visiting Scotland believe they are real) that has legs that are longer on one side than the other. There are two varieties: in one the right fore and hind limb are shorter and the other, of course, the left. The asymmetry helps the haggis to circumnavigate the steep mountainsides of its native terrain, but only in a clockwise (if the right legs are short) or counter clockwise (if the left legs are short) direction, so as to not roll down the steep hillside and come to an untimely death; this is purported to be one of the reasons for their near extinction (the other was the introduction of sheep).

The two species coexist peacefully but are unable to interbreed in the wild because in order for the male of one variety to mate with a female of the other, he must turn to face in the same direction as his intended mate, causing him to lose his balance before he can mount her. As a result of this difficulty, differences in leg length among the haggis population are further accentuated, as is there dwindling numbers.

image source:

image source:

It’s an amusing concept, but unfortunately there’s a non-mythical human corollary: Leg-length discrepancies (LLDs), which do not discriminate and affect a wide variety of people, including children with cerebral palsy, people who’ve had hip and knee replacements, and those with scoliosis, pelvic obliquity, or certain muscle contractures/dysfunctions.

Haggis is actually a Scottish dish; lungs and liver of a sheep cooked with other ingredients inside its stomach. Yum (Not!) We are not sure why or how the two are related but it does make for an interesting post : )

Learn more about LLD’s and their compensations by joining us Wednesday, April 17th 5 PST, 6MST, 7CST and 8 EST on Biomechanics 307

Dr Ivo Waerlop, one of The Gait Guys

#haggis #wildhaggis #LLD #leglengthdiscrepancy #leglengthdifference #leglengthinequality #gait #thegaitguys

There is more than one way around an LLD....

Leg length discrepancies. Love them, hate them, they happen. They can be either functional, anatomical or both.

No matter what the cause, there are numerous ways to compensate for a leg length discrepancy. Today we are going to look at one of the more common ones, "leaning" to the short leg side to create enough clearance for the opposite lower extremity. This patient has a left sided short leg. Note how he abducts his pelvis, utilizing both the stance limb gluteus medius and swing limb quadratus lumborum of the left leg to create enough space to swing the right leg through.

Want to know more about LLD’s and their compensations? Join us on, Wednesday, April 17th for Biomechanics 307. 6 PM Mountain time. See you there!

Dr Ivo Waerlop, one of The Gait Guys.

#LLD #leglengthdifference #leglengthdiscrepancy #leglengthinequality #compensation #gait #gait analysis #thegaitguys

Got hip extension?

Because she sure could use some...

we have see this gal before… yesterday in fact

  • left plantar plate lesion (yes, conformed on ultrasound)

  • left sided anatomical leg length discrepany

  • bilateral internal tibial torsion

  • incompetent L quadratus lumborum

  • adequate hip extension and ankle dorsiflexion available to her

  • lack of endurance in her abs

yep, lots more, but that is enough for now

note that she has plenty of ankle dorsiflexion, more on the right. this is due to her right leg being anatomically longer and has to travel through a greater range of motion

look at the knee and the hip articulations to assess hip extension. It should match ankle dorsiflexion, no?

Dr Ivo Waerlop, one of The Gait Guys

#gait #gaitguys #thegaitguys #hipextension #LLD #quadratuslumborum #internaltibialtorsion #anklerocker #ankledorsiflexion

3 things

Its subtle, but hopefully you see these 3 things in this video.

I just LOVE the slow motion feature on my iPhone. It save me from having to drag the video into Quicktime, slow it down and rerecord it.

This gal has a healing left plantar plate lesion under the 2nd and 3rd mets. She has an anatomical leg length deficiency, short on the left, and bilateral internal tibial torsion, with no significant femoral version. Yes, there are plenty of other salient details, but this sketch will help.

  1. 1st if all, do you see how the pelvis on her left dips WAY more when she lands on the right? There is a small amount of coronal plane shift to the right as well. This often happens in gluteus medius insufficiency on the stance phase leg (right in this case), or quadratus lumborum (QL) deficiency on the swing phase leg (left in this case) or both. Yes, there are other things that can cause this and the list is numerous, but lets stick to these 2 for now. In this case it was her left QL driving the bus.

  2. Watch the left and right forefeet. can you see how she strikes more inverted on the left? this is a common finding, as the body often (but not always) tries to supinate the shorter extremity (dorsiflexion, eversion and adduction, remember?) in an attempt to “lengthen” it. Yes, there is usually anterior pelvic tilt accompanying it on the side, because I knew you were going to ask : )

  3. Look how her knees are OUTSIDE the saggital plane and remain there in her running stride. This is commonly seen in folks with internal tibial torsion and is one of the reasons that in our opinion, these folks should not be put medially posted, torsionally rigid, motion control shoes as this usually drive the knees FURTHER outside the saggital plane and can macerate the meniscus.

Yep, lots more we could talk about on this video, but in my opinion, 3 is a good number.

Dr Ivo Waerlop, one of The Gait Guys

#thegaitguys #gaitanalysis #footpain #gaitproblem #internaltibialtorsion #quadratuslumborum #footstrike

LLD's and Achilles Tendinopathy

Sometimes, it doesn't matter whether it is long or short.

 Achilles tendinopathy .. there are many factors that can contribute. Have you considered leg length inequality? Generally speaking, People have a tendency to overpronate on the longer leg side and under prone only shorter leg side with strain on the medial and lateral aspects of the Achilles tendon respectively. It would make sense that this could be a contributing factor.

 "The mean inequality in length of legs (ILL) was 5 +/- 4 mm. Among the 48 patients with ILL > or = 5 mm, the side affected with ruptured tendon was longer in 48% of cases and shorter in 52%. "

Age and pathology can play a role with younger, healthy tender and having greater compliance.

Proprioception is impaired on the affected side of folks with Achilles tendinopathy. This is a "chicken and the egg" scenario. Did impaired proprioception cause the tendinopathy or is the tendinopathy causing the impaired proprioception? Probably, a little bit of both.

Dr Ivo, one of The Gait Guys

Leppilahti J, Korpelainen R, Karpakka J, Kvist M, Orava S. Ruptures of the Achilles tendon: relationship to inequality in length of legs and to patterns in the foot and ankle. Foot Ankle Int. 1998 Oct;19(10):683-7.

Scholes M, Stadler S, Connell D, Barton C, Clarke RA, Bryant AL, Malliaras P. Men with unilateral Achilles tendinopathy have impaired balance on the symptomatic side. J Sci Med Sport. 2018 May;21(5):479-482. doi: 10.1016/j.jsams.2017.09.594. Epub 2017 Oct 6.

Intziegianni K, Cassel M, Rauf S, White S, Rector M, Kaplick H, Wahmkow G, Kratzenstein S, Mayer F. Influence of Age and Pathology on Achilles Tendon Properties During a Single-leg Jump. Int J Sports Med. 2016 Nov;37(12):973-978. Epub 2016 Aug 8.

#achilles,#tendon, #achillestendon, #tendinopathy, #proprioception

Got Short leg?

Ahhhh. They get it!


Our favorite quote from this article " Understanding limb-length compensation
We encourage you to pay as much attention to any abnormal compensation pattern as you do to the LLD itself. It is well documented that abnormal biomechanics, such as you would find in a compensatory pattern, can result in vibratory forces and microtrauma along the closed kinetic chain (Figure 1). The spinal facet; hip, knee, ankle and foot joints; and their associated muscles may suffer repetitive microtrauma resulting in sprain, strain, or degenerative joint disease. By addressing compensatory neuro-musculoskeletal function, you may be able to assist the patient with a cascade of dysfunction through the musculoskeletal system.

We also encourage you to make use of gait assessment technology to quantify, document, and monitor patients’ progress. Application of reproducible, documented metrics is essential to communicate effectively within a multidisciplinary system that is committed to practicing evidence-based medicine."


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.