The case of the lateral thigh, leg and knee pain

note how the bottom of the heel cup is rounded

This gal  came to see us with pain in the lateral thigh, knee, and lateral lower leg on the left. It has happened recently with skiing and alleviated only temporarily with acupuncture of the vastus lateralis and peroneal groups. She has been skiing with a foot bed (please see picture).

Evaluation reveals mild bilateral external tibial torsion, a right anatomically short  leg tibial, and bilateral medial knee fall (knee is medial of the sagittal plane) L>R during weight-bearing when the feet are pointing straight ahead. There is moderate loss of the medial longitudinal arches bilaterally, greater on the left.

We remember that when a patient has external tibial torsion, when the knees points straight the feet point to the outside. 

Translated to skiing, the feet need to be straightahead which brings the knee(s) inside of the sagittal plane. 

We remember that often times with leg length discrepancy is, the longer leg side will “pronate ” in attempt to shorten extremity and the shorter leg side “supinate”, in an attempt to lengthen the extremity.

Putting this all together:  the patient is pronating bilaterally, left greater than right with medial knee fall. The ski shop put the footbed you see in the picture in both of the patients boots. You can see that it is extremely rounded at the heel and, because orthotics are shank dependent devices, a round heel like this will just roll into pronation as there is more weight on the medial longitudinal arch. This makes the entire foot bed assembly relatively ineffective and increases the valgus moment at the knee, stressing the vastus lateralis as it is trying to pull the knee to midline as well as the peroneal group as it is trying to do the same from a closed chain position as well as supinate the foot. 

We placed a 3 mm sole lift under the right foot and added a post to the bottom the left orthotic to allow it to sit flat. This did not correct the problem completely and we needed to add a Morton’s toe extension (post under the first metatarsal) to invert the foot and bring the knee out into the sagittal plane.

Dr Ivo Waerlop, one of The Gait Guys 

#footbeds #kneepain #orthotics #skibootfit #thighpain #legpain #quadriceps

Unilateral increased tibial varum; one reason why...

Take a look at this gent in the picture. Do you notice anything peculiar? Pick a point and start either moving from above down or from the ground up.

From the ground up, the first thing you may notice is that he has a hallux abducto valgus on the right side. This could be for any number of reasons and what it actually tells you is that he is unable to anchor his first ray to the ground and have appropriate function of the adductor hallucis. Your job, during the examination process, is to sort that out.

The second thing you may notice is that he has more midfoot collapse on this same side. You would think that with that much midfoot collapse he would get his first ray to the ground but that’s obviously not the case.

Moving up from there, you may have noticed that he has significantly more tibial varum on the left-hand side. Tibial varum should be about 4-6 degrees and is largely a function of in utero positioning although diseases like osteomalacia and rickets can increase it though this is often more bilaterally symmetrical.

You need to be aware increased tibial varum means that the foot, particularly the forefoot, needs to pronate a greater degree to create a stable foot tripod on the ground. You need to ensure during the examination process that adequate range of motion in the forefoot and 1st ray are available.

You may have noticed that there is prominence of the left medial head of the gastroc which is most likely a combination of positioning as well as increased mechanical advantage secondary to the varum.

Hopefully you noticed that the knees are (relatively) in the sagittal plane and that there’s an increase progression angle on the left-hand side. If you drop a plumbline from the tibial tuberosity you’ll see the falls medial to the second metatarsal shaft indicating external tibial torsion in the lower extremity.

The unilateral increased tibial varum on the left-hand side is secondary to an anatomical leg length discrepancy where the right tibia is shorter. This has been long-standing and in compensation, the left tibia has “bowed“ to compensate for the difference, In an attempt to shorten the left leg.

Dr Ivo Waerlop, one of The Gait Guys

Like this stuff? Come and drink from the fire hydrant. Consider joining us this Wednesday evening on online CE.com for bio mechanics 326, 6 PM Mountain standard time. Likewise, you can become a Patreon supporter and get this kind of information every week.

#tibialvarum #leglengthdiscrepancy #lld #bowedlegs #pronation

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 Shamaei, GS Sawicki, AM Dollar Estimation of quasi-stiffness and propulsive work of the human ankle in the stance phase of walking - PloS one, 2013 - journals.plos.org

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.

Support for visual gait analysis... with respect to leg length discrepancies

image credit: https://pixabay.com/photos/eye-blue-eyelashes-vision-make-up-691269/

We talk about leg length discrepancies all the time here on the blog and sometimes, how small discrepancies cause changes in peoples biomechanics. The gold standard for measuring a leg length difference is full length lower extremity X ray, but this presents a problem due to the ionizing radiation, accessibility as well as impracticality of X rays every person with a suspected difference.

We have talked about different compensations as to how to get around a leg length discrepancies. Last week we actually did a tell a seminar on this entire subject. Your patient or client needs to “create clearance” for the longer leg side. This can be accomplished in many ways.

The 5 most common strategies (keep in mind there are many more) are:

• lean the torso to the short leg side (essentially hip adduction of the longer side)

• hike the torso on the long leg side

• circumduct the longer lower extremity

• increase plantar flexion of the calf of the short leg side

• increase hip and knee flexion on the longer leg side

And that is exactly what this study found. They looked at kinematics in people with anatomical leg length discrepancies and found that hip adduction as well as increased hip and knee flexion were 2 variables that were consistent in folks with anatomical differences and suggest these variables are a useful screening tool.

Paying attention to how people move and looking for asymmetries. In our opinion, that’s the name of the game : )

Dr Ivo Waerlop, on of The Gait Guys

Zeitoune G, Nadal J, Batista LA, Metsavaht L, Moraes AP, Leporace G.Prediction of mild anatomical leg length discrepancy based on gait kinematics and linear regression model. Gait Posture. 2019 Jan;67:117-121. doi: 10.1016/j.gaitpost.2018.09.027. Epub 2018 Sep 29.

#LLD #leglengthdifference #leglengthinequality #visualgaitanalysis #thegaitguys #gaitanalysis

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: https://en.wikipedia.org/wiki/Wild_haggis#/media/File:Haggis_scoticus.jpg

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 onlinece.com: Biomechanics 307

Dr Ivo Waerlop, one of The Gait Guys

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

https://en.wikipedia.org/wiki/Wild_haggis

https://lermagazine.com/article/limb-length-discrepancy-when-how-to-intervene

https://www.atlasobscura.com/articles/what-is-haggis

https://www.thehaggis.com/wild-haggis-all-about-haggis/

https://www.undiscoveredscotland.co.uk/usfeatures/haggis/wildhaggis.ht

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 onlinece.com, 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

Subtle clues to an LLD?

Leg length discrepancies, whether their functional anatomical, have biomechanical consequences north of the foot. This low back pain patient exhibited 2 signs. Can you tell what they are?

can you see the difference ?

how about now?

compare right to left

compare right to left

can you see the difference in the Q angles?

Look at the first picture and noticed how the left knee is hyper extended compared to the right. Sometimes we see flexion of this extremity. This is to "functionally shorten" that extremity.

Now look at the Q angles. Can you see how the left QL angle is greater than the right? This usually results from a long-term leg length discrepancy where the body is attempting to compensate by increasing the valgus angle of that knee, effectively shortening the extremity.

Dr Ivo Waerlop, one of The Gait Guys

#subtle #clues #LLD #leglengthdiscrepancy #leglengthinequality #thegaitguys #gaitabnormality

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

https://vimeo.com/329212767

You are wondering: "Does the distance between footfalls make a difference?"

In short, when it comes to stress fractures, IT band syndrome and patellofemoral pain, the literature says yes…

"In conclusion, decreasing stride length has been proposed as a method to treat and prevent running-related musculoskeletal injuries. While not directly examining the effect of stride length, research examining the effect of barefoot running and minimalist shoes indirectly evaluates stride length, as barefoot/minimalist runners tend to adopt a reduced stride length. Evidence suggests that decreasing stride length results in biomechanical changes, including reduced GRFs and joint moments, that can contribute to reduced injury risk. Clinical studies indicate that reducing stride length may help decrease the likelihood of stress fractures, iliotibial band syndrome, and patellofemoral pain."

a good read: https://lermagazine.com/article/implications-of-reduced-stride-length-in-running. ALSO the photo credit

#gait, #thegaitguys, #gaitanalysis, #running, #stridelength

Dr Ivo, one of The Gait Guys

What does a pedograph of a person with hallux limitus look like?

Take a good look at the pedographs above. Can you figure out which side has the hallux limitus from the pictures? 

You would think that with hallux limitus there would be increased printing over the distal phalanx of great toe and possibly over the distal metatarsal as seen in the print of the right foot. This would make sense as if you have limited motion here and the pressure will be more forward. However, often times Hallux limitus is painful and the patient develops a compensation to NOT load the joint, as we see on the print of the left foot. We see the lack of printing under the first metatarsal head and increased printing laterally in the foot from avoidance of that joint. Also notice a slight increased printing in the right heel teardrop (hash marks are more filled in) and slight widening of it anteriorly. He has a right sided leg length discrepancy and we would normally expect an increased amount of pronation on the longer leg side, however because of the weight shift to the left we are seeing increased pronation on the right. Now, with this valgus moment of the right foot do you understand why the printing is so heavy under the first metatarsal and distal phalanx. Note also the increased printing at the distal phalanx of toes number two, three and five on the right hand side in an attempt to stabilize as his center of gravity shifts to the right.

And now you know!

Dr Ivo, one of The Gait Guys

#halluxlimitis, #gaitanalysis, #pedograph, #leglengthdiscrepancy, #LLD

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

More subtle clues..LLD's

This gentleman presented to the office with left-sided knee pain at the medial collateral ligament following a cutting injury, moving from right to left with the left foot planted. As you can see, he has an anatomical leg length discrepancy with tibial and probable femoral length deficiencies on the left side. Can you see the subtle, increased tone of the long flexors of the toes on the left hand side as it evidenced by the increased prominence of the long extensor tendons to a greater degree on the shorter side? This is a common compensation seen in true leg length discrepancies with clawing of the toes in attempt to create stability on the shorter leg side. Often times, the progression angle on the shorter side will be increased as well.

And why does this guy have hip pain?

line up the center of the heel counters with the outsoles, and what do you see?

can you see how the heel counter is centered on the outsole, like it is supposed to be

notice how the heel counter of the shoe is canted medially on the outsole of the shoe, creating a varus cant

Take a guy with lower back and left sided sub patellar pain that also has a left anatomically short leg (tibial) and bilateral internal tibial torsion and put him in these baby’s to play pickleball and you have a prescription for disaster.

Folks with an LLD generally (soft rule here) have a tendency to supinate more on the short leg side (in an attempt to make the limb longer) and pronate more on the longer leg side (to make the limb shorter). Supination causes external rotation of the lower limb (remember, we are trying to make the foot into a rigid lever in a “normal” gait cycle). this external rotation with rotate the knee externally (laterally). Folks with internal tibial torsion usually rotate their limb externally to give them a better progression angle (of the foot) so they don’t trip and fall from having their feet pointing inward. This ALSO moves the knee into external rotation (laterally), often moving it OUTSIDE the saggital plane. In this case, the knee, because of the difference in leg length AND internal tibial torsion AND the varus cant of the shoe, has his knee WAY OUTSIDE the saggital plane, causing faulty patellar tracking and LBP.

Moral of the story? When people present with a problem ALWAYS TAKE TIME TO LOOK AT THEIR SHOES!

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

Achilles tendinopathy (AT) .. 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%. " (1)

Age and pathology can play a role with younger, healthy tendons having greater compliance, with compliance being considered a risk factor for AT.(2)

Proprioception is impaired on the affected side of folks with Achilles tendinopathy (3). 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.

All this and more to be discussed in one of the 3 cases we will discuss tomorrow evening, Wednesday, August 15th on onlinece.com: Biomechanics 320   5PST, 6 MST, 7 CST, 8 EST

Hope to see you there!

1. 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.

2. 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.

3. 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.

Flip Flops not so bad? We still think they suck and here's why...

We have talked about the dangers of open back shoes (Including flip-flops)  and loss of ankle rocker as well as changes in forefoot rocker and great toe dorsiflexion on our blog many times.

The findings of this study, with slower cadence and shortened stance are not surprising (especially since you need to fire your long flexors to keep them on!) nor are ankle joint kinematics (flip flops have no heel counter and are not torsionally rigid, so naturally there would be increseased subtalar motion), however we really question the interpretation.

 "Many have long suspected the answer, but a new study would appear to resolve the question: Are flip flops really that bad for your feet? According to Chen and colleagues from the Department of Biomedical Engineering at The Hong Kong Polytechnic University, flip flops are most likely no better than barefoot when it comes to lower-limb co-contraction and joint contact force in the ankle. The authors had hypothesized that the popular rubber footwear would increase co-contraction of the muscles between the knee and ankle joints in what they thought was a compensatory mechanism for the unstable foot–sole interface and would affect gait kinematics and kinetics.

In the study, the researchers had 10 healthy males perform 6 walking trials under 3 conditions: barefoot, sports shoes, and thong-type flip flops. Participants, who reported they were not “regular flip flop wearers,” were fitted with numerous markers that were monitored while they walked on a 10-meter pathway. The study looked at several muscle pairings that stabilize the knee, ankle, and subtalar joints, including vastus lateralis and gastrocnemius medialis; vastus lateralis and biceps femoris; and peroneus longus and tibialis anterior.

In pairwise comparisons, the walking velocity of flip flops was lower than that of sports shoes (p<0.01) but comparable to barefoot (p>0.05), findings that were consistent with the published literature. Although not significant, the minimalist footwear produced a slower cadence and shortened stance phase in walking trials compared to the other 2 types of footwear. Joint kinematics differed significantly in the ankle joint (F[2,18]=6.73, P<.05) and subtalar joint (F[2,18]=4.45; P<.05); Furthermore, ankle and subtalar range of motion was higher for flip flops than for sports shoes. However, co-contraction was not enhanced. The authors propose that walking speed does not need to be consistent for real-world activities and the slower speed could be a natural approach to avoid injury.

The authors conclude that the slowed walking speed of flip flop users could account for the comparable joint biomechanics between flip flop use and barefoot. They note, however, that, for injury prevention, the closed-toe design of the sports shoe would provide better support for joint motion and loading compared to the other 2 options."

Source:

Chen TL, Wong DW, Xu Z, Tan Q, Wang Y, Luximon A, Zhang M. Lower limb muscle co-contraction and joint loading of flip-flops walking in male wearers. PLoS One. 2018;13(3):e0193653."

image and article source: http://lermagazine.com/issues/may/flip-flops-bare-feet-or-sports-shoes-which-are-best-and-which-are-worst

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."

http://lermagazine.com/cover_story/assessing-limb-length-discrepenacy

Parkinsons Patients? How about textured insoles or walking barefoot more?

Is it at all surprising that increasing afferent input (in this case: textured insoles) to one of the areas in the brain (parasaggital sulcus in the post central gyrus) from one of the structures that has the greatest cortical representation (ie the feet) can improve gait on folks that have a disorder with their basal ganglia (which provides background positioning of joints)?

"After one week of insole wear, plantar sensation and stride length were significantly improved relative to baseline; the improvement in plantar sensation was maintained after another week of wearing conventional insoles."

Lirani-Silva E, Vitorio R, Barbieri FA, et al. Continuous use of textured insole improve plantar sensation and stride length of people with Parkinson disease: A pilot study. Gait Posture 2017;58:495-497.

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.