Do you know your Torsions? If so, then you here is what you need to know about twisted people...

Are you twisted? Are your patients/clients twisted? You know about tibial torsions from yesterday but do you know about femoral torsions?

To go along with yesterdays post, here is some more info on femoral torsions. If you missed it, click here

The degree of version is the angle between an imaginary line drawn through the condyles of the femur and an imaginary line drawn through the head and neck of the femur. This is often referred to as the femoral neck angle or FNA.

IMAGE SOURCE: Michael T Cibulka; Determination and Significance of Femoral Neck Anteversion,  Physical Therapy , Volume 84, Issue 6, 1 June 2004, Pages 550–558,  https://doi.org/10.1093/ptj/84.6.550

IMAGE SOURCE: Michael T Cibulka; Determination and Significance of Femoral Neck Anteversion, Physical Therapy, Volume 84, Issue 6, 1 June 2004, Pages 550–558, https://doi.org/10.1093/ptj/84.6.550

Beginning about the 3rd month of embryological development (Lanz and Mayet 1953) the femoral neck angle reaches 60 degrees and decreases, with growth, to about 40 degrees (with an average of 30-60 degrees) at birth. It then decreases 25-30 degrees by adulthood to 8-20 degrees with males being at the lower and females at the upper end of the range.

The FNA angle, therefore, diminishes about 1.5 degrees a year until about 15 years of age. Femoral neck anteversion angle is typically symmetrical from the left side to the right side.

What causes torsion in the first place? By the sixth month in utero, the lumbar spine and hips of the fetus are fully flexed, so perhaps it is positional. Other sources say it coincides with the degree of osteogenesis. There is a growing consensus that muscular forces are responsible, particularly the iliopsoas or possibly the medial and lateral hip rotators.

Additional changes can occur after birth, particularly with sitting postures. “W” sitting or “cross legged” sitting have been associated with altering the available range of motion and thus the FNA, with the range increased in the direction the hip was held in; W sitting causing increased internal rotation and antetorsion and cross legged causing external rotation and retro torsion.

image source: T Michaud, with permission

image source: T Michaud, with permission

As discussed previously, there are at least 3 reasons we need to understand torsions and versions, They can alter the progression angle of gait, they usually affect the available ranges of motion of the limb and they can alter the coronal plane orientation of the limb.

  1. fermoral torsions often alter the progression angle of gait. In femoral antetorsion torsion, the knees often face inward, resulting in an intoed gait and a decreased progression angle of the foot. This can be differentiated from internal tibial torsion (ITT) by looking at the tibia and studying the position of the tibial tuberosity with respect to the foot, particularly the 2nd metatarsal. In ITT, the foot points inward while the tibial tuberosity points straight ahead. In an individual with no torsion, the tibial tuberosity lines up with the 2nd metatarsal. If the tibial tuerosity and 2nd met are lined up, and the knees still point inward, the individual probably has femoral ante torsion. Remember that a decreased progression angle is often associated with a decreased step width whereas an increased angle is often associated with an increased step width.

  2. Femoral torsions affect available ranges of motion of the limb. We remember that the thigh leg needs to internally rotate the requisite 4-6 degrees from initial contact to midstance (most folks have 40 degrees) If it is already fully internally rotated (as it may be with femoral retro torsion), that range of motion must be created or compensated for elsewhere. This, much like internal tibial torsion, can result in external rotation of the affected lower limb to create the range of motion needed.

  • Femoral retro torsion results in less internal rotation of the limb, and increased external rotation.

  • Femoral ante torsion results in less external rotation of the limb, and increased internal rotation.

          3. femoral torsions usually do not effect the coronal plane orientation of the lower limb,      since the “spin” is in the transverse or horizontal plane.

The take home message here about femoral torsions is that no matter what the cause:

  • FNA values that exist one to two standard deviations outside the range are considered “torsions”

  • Decreased values (ie, less than 8 degrees) are called “retro torsion” and increased values (greater than 20 degrees) are called “ante torsion”

  • Retro torsion causes a limitation of available internal rotation of the hip and an increase in external rotation

  • Ante torsion causes an increase in available internal rotation of the hip and decrease in external rotation

  • Femoral ante torsion will be perpetuated by “W” sitting (sitting on knees with the feet outside the thighs, promoting internal rotation of the femur)

  • Femoral antetorsion will be perpetuated by sitting cross legged, which forces the thigh into external rotation.

Michael T Cibulka; Determination and Significance of Femoral Neck Anteversion, Physical Therapy, Volume 84, Issue 6, 1 June 2004, Pages 550–558, https://doi.org/10.1093/ptj/84.6.550

http://www.clinicalgaitanalysis.com/faq/torsion.html

Souza AD, Ankolekar VH, Padmashali S, Das A, Souza A, Hosapatna M. Femoral Neck Anteversion and Neck Shaft Angles: Determination and their Clinical Implications in Fetuses of Different Gestational Ages. Malays Orthop J. 2015;9(2):33-36.

A primer on tibal torsions and versions....

We get tired of reading posts on squats, lifting, lunges and the whole “have your toes in”, “Have your tires pointing out”, “keep your feet straight” sort of advice for best performance. The truth of the matter is, when the knee is in the saggital plane, you will have the best results and cause the least amount of damage to the knee and menisci. In our opinion, if you are not paying attention to femoral and tibial torsions and versions, you are missing the boat.

This is not a post for the faint of heart, but hopefully will help clear up some questions you may (or may not) have had. Grab a cup of your favorite beverage and enjoy...

The tibia and femur are more prone to torsional defects, as they are longer lamellar (layered) bones as opposed to the cancellous bone that makes up the talus. These often present as an “in toeing” or “out toeing” of the foot with respect to the leg; changing the progression angle of gait.

Tibial versions and torsions can be measured by the “thigh foot angle” (the angulation of the foot to the thigh with the leg bent 90 degrees: above right) or the “transmalleolar angle” (the angle that a line drawn between the medial and lateral malleoli of the ankle makes with the tibial plateau).

At a gestational age of 5 months, the fetus has approximately 20° of internal tibial torsion. As the fetus matures, The tibia then rotates externally, and most newborns have an average of 0- 4° of internal tibial torsion. At birth, there should be little to no torsion of the tibia; the proximal and distal portions of the bone have little angular difference (see above: top). Postnatally, the tibia should twist outward (externally) a total of 1.5 degrees per year until adult values are reached between ages 8 and 10 years of 23° of external tibial torsion (range, 0° to 40°).

Sometimes the rotation at birth is excessive. This is called a torsion. Five in 10,000 children born will have rotational deformities of the legs. The most common cause is position and pressure (on the lower legs) in the uterus (an unstretched uterus in a first pregnancy causes greater pressuremaking the first-born child more prone to rotational deformities. Growth of the unborn child accelerates during the last 10 weeks and the compression from the uterus thus increases. As you would guess, premature infants have less rotational deformities than full-term infants. This is probably due to decreased pressure in the uterus. Twins take up more space in the uterus and are more likely to have rotational deformities.

Of interesting note, there is a 2:1 preponderance of left sided deformities believed to be due to most babies being carried on their backs on the left side of the mother in utero, causing the left leg to overlie the right in an externally rotated and abducted position.

Normal ranges of versions and torsions are highly variable. Ranges less than 2 standard deviations are considered internal tibial torsion and greater external tibial torsion.

Internal tibial torsion (ITT) usually corrects 1 to 2 years after physiological bowing of the tibia (ie tibial varum) resolves. External tibial torsion (TT) is less common in infancy than ITT but is more likely to persist in later childhood and NOT resolve with growth because the natural progression of development is toward increasing external torsion.

Males and females seem to be affected equally, with about two thirds of patients are affected bilaterally and the differences in normal tibial version values are often expected to be cultural, lifestyle and posture related.

The ability to compensate for a tibial torsion depends on the amount of inversion and eversion present in the foot and on the amount of rotation possible at the hip. Internal torsion causes the foot to adduct, and the patient tries to compensate by everting the foot and/or by externally rotating at the hip. Similarly, persons with external tibial torsion invert at the foot and internally rotate at the hip. Both can decrease walking agility and speed if severe. With an external tibial torsion deformity of 30 degrees , the capacities of soleus, posterior gluteus medius, and gluteus maximus to extend both the hip and knee were all reduced by over 10%.

So, there you have it. Ina nutshell, the basics that will take you far and wide on your journey to better performance and biomechanics for yourself and your patients/clients.

 

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What would you do? This is what we did.

History:

This 7 year old girl is brought in by her mother because of knee misalignment while skiing, L > R. No history of trauma; normal term birth with no complications. No knee pain. Of incidental note, she is deaf in the left ear.

Exam findings:

She has bi-lat. external tibial torsion, left much worse than right (40 degrees transmallolear angle vs 22 degrees. for info on measuring torsions, click here). remember, you should be able to draw a line from the tibial tuberosity down through the 2nd metatarsal head. 

She has a 5mm anatomical leg length deficiency on the right (see top above left).

She has femoral antetorsion right side with very little external rotation, approximately 10 degrees,  internal rotation is in excess of 50.  Left side has normal femoral versions (for a review of femoral versions and torsions, click here).  See last 2 pictures which are full internal and external rotation respectively.

She has a mild uncompensated forefoot varus (cannot really see from the pictures, you will need to take our word for it) with a relatively cavus arch to her foot(see center and last picture on right.

Neurologically, she appeared to have integrity with respect to sensation, motor strength and deep tendon reflexes in the lower extremities.

Assessment:

Pathomechanical alignment as described.  Severe left external tibial torsion. MIld to moderate right. Femoral antetorsion right.

Plan:

We are going to build her a medium heel cup full length modified UCB orthotic inverting the cast bi-lat. left greater than right.  We gave her  balance and coordination exercises, heel walking, lift/spread/reach and one leg balancing. She will follow up for a dispense.  Her mother will try to get a better fitting ski boot as the one she has currently is two sizes too big. She will return for a dispense. She should consider wearing the orthotics in everyday footwear as well. We will do a follow up post in a few weeks. 

The Gait Guys. Teaching you something new in each and every post. Like this post? Tell and share it with a friend. Don’t like this post? Let us know!

The Power of Observation: Part 2

Let’s take a closer look at yesterdays post and the findings. If you are just picking up here, the post will be more meaningful if you go back and read it. 


The following are some explanations for what you were seeing:

torso lean to left during stance phase on L?

if he has a L short leg, he will need to clear right leg on swing phase. We have spoken of strategies around a short leg in another post. This gentleman employs 2 of the 5 strategies; torso lean is one of them

increased progression angle of both feet?

Remember he has femoral retroversion. You may have read about retrotorsion here. He has limited internal rotation o both thighs and must create the requisite 4-6 degrees necessary to walk. He does this by spinning his foot out (rotating externally).

decreased arm swing on L?

This is most likely cortical, as he seems to have decreased proprioception on both legs during 1 leg standing. Proprioception feeds to the cerebellum, which in turn fires axial extensors through connections with the vestibular system. Diminished input can lead to flexor dominance (and extensors not firing). Note the longer stride forward on the right leg compared to the left with less hip extension (yes, we know, a side view would be helpful here).

circumduction of right leg?

This is the 2nd strategy for getting around that L short leg.

clenched fist on L?(esp when standing on either leg)

see the decreased arm swing section. This is a subtle sign of flexor dominance, which appears to be greater on the right.

body lean to R during L leg standing?

This is again to compensate for the L short leg. He has very mild weakness of the left hip abductors as well, more when moving or using them in a synergistic fashion (ie functional weakness) than to manual testing.

Well, what do you think? Now you can see how important the subtle is and that gait analysis may complex than many think.

We are and we remain, the Geeky Guru’s of Gait: The Gait Guys

OK, quiz time. The Powers of Observation.

Perhaps you have been following us for a while, perhaps you are just finding us for the 1st time. Here is some back ground on this footage. Let’s test you observation skills.

Watch this gait clip a few times and come back here to read on.

This triathlete presented with low chronic low back pain of about 1 years duration. The   pain gets worse as the day goes on; it is best in the early am. Running and biking do not alter its intensity or character and swimming makes it worse. Rest and analgesics provide only temporary relief.

Physical exam findings include limited internal rotation of both hips (zero); a left anatomical short leg (tibial and femoral, 5mm total); diminished proprioception with 1 leg standing (<30 seconds). MRI reveals fatty infiltration of the lumbar spinal paraspinals and fibrotic changes within the musculature; degenerative changes in the L4 and L5 lumbar facet joints, degeneration of the L5-S1, L3-L4 and L2-L3 lumbar discs.

Now watch his gait again and come back here for more.

Did you see the following?

  • torso lean to left during stance phase on L?
  • increased progression angle of both feet?
  • decreased arm swing on L?
  • circumduction of right leg?
  • clenched fist on L?(esp when standing on either leg)
  • body lean to R during L leg standing?


How did you do? If you didn’t see all those things, then you are missing pieces of the puzzle. Remember, often what you see is not what is wrong, but the compensation

The powers of observation of the subtle make the difference between good results and great ones.

Try some of these tips.

  • break down the gait into smaller parts by watching one body part at a time: right leg, left leg, right arm, left arm, etc
  • watch for shifts in body weight in the coronal plane (laterally) and saggital plane (forward/backward) as weight transfers from one leg to another
  • watch for torso rotation (watch his shoulders. Did you notice he brings his torso more forward on the left than right when walking toward us?)


We are (and have been) here to help you be a better observer and a better clinician, coach, athlete, sales person, etc. If you haven’t already, join us here for some insightful posts each week; for our weekly (almost) PODcast on iTunes; follow us on Twitteror on Facebook: The Gait Guys

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Twisted, Part 4

 

Hopefully you have been keeping us with us. If you missed the 1st 3 of this series, go back 3 weeks and start reading again, or do a search on the blog page for “torsion”.

The final chapter of developmental versions involves the femur. The degree of version is the angle between an imaginary line drawn through the condyles of the femur and an imaginary line drawn through the head and neck of the femur. This is often referred to as the femoral neck angle or FNA.

Beginning about the 3rd month of embryological development (Lanz and Mayet 1953) and reaches about 40 degrees (with an average of 30-60 degrees) at birth. It then decreases 25-30 degrees by adulthood to 8-20 degrees with males being at the lower and females at the upper end of the range.

The FNA angle, therefore, diminishes about 1.5 degrees a year until about 15 years of age. Femoral neck anteversion angle is typically symmetrical from the left side to the right side.

What causes torsion in the first place? By the sixth month in utero, the lumbar spine and hips of the fetus are fully flexed, so perhaps it is positional. Other sources say it coincides with the degree of osteogenesis. There is a growing consensus that muscular forces are responsible, particularly the iliopsoas  or possibly the medial and lateral hip rotators.

Additional changes can occur after birth, particularly with sitting postures. “W” sitting or “cross legged” sitting have been associated with altering the available range of motion and thus the FNA, with the range increased in the direction the hip was held in; W sitting causing increased internal rotation and antetorsion and cross legged causing external rotation and retro torsion.

As discussed previously, there are at least 3 reasons we need to understand torsions and versions, They can alter the progression angle of gait, they usually affect the available ranges of motion of the limb and they can alter the coronal plane orientation of the limb.

1. fermoral torsions often alter the progression angle of gait.  In femoral antetorsion torsion, the knees often face inward, resulting in an intoed gait and a decreased progression angle of the foot. This can be differentiated from internal tibial torsion (ITT) by looking at the tibia and studying the position of the tibial tuberosity with respect to the foot, particularly the 2nd metatarsal. In ITT, the foot points inward while the tibial tuberosity points straight ahead. In an individual with no torsion, the tibial tuberosity lines up with the 2nd metatarsal. If the tibial tuerosity and 2nd met are lined up,  and the knees still point inward, the individual probably has femoral ante torsion. Remember that a decreased progression angle is often associated with a decreased step width whereas an increased angle is often associated with an increased step width. See the person with external tibial torsion in the above picture?

2. Femoral torsions affect available ranges of motion of the limb. We remember that the thigh leg needs to internally rotate the requisite 4-6 degrees from initial contact to midstance (most folks have 40 degrees) If it is already fully internally rotated (as it may be with femoral retro torsion), that range of motion must be created or compensated for elsewhere. This, much like internal tibial torsion, can result in external rotation of the affected lower limb to create the range of motion needed.

Femoral retro torsion results in less internal rotation of the limb, and increased external rotation.

Femoral ante torsion results in less external rotation of the limb, and increased internal rotation.

3. femoral torsions usually do not effect the coronal plane orientation of the lower limb, since the “spin” is in the transverse or horizontal plane.

The take home message here about femoral torsions is that no matter what the cause:

  •  FNA values that exist one to two standard deviations outside the range are considered “torsions”

  • Decreased values (ie, less than 8 degrees) are called “retro torsion” and increased values (greater than 20 degrees) are called “ante torsion”
  • Retro torsion causes a limitation of available internal rotation of the hip and an increase in external rotation

  • Ante torsion causes an increase in available internal rotation  of the hip and decrease in external rotation
  • Femoral ante torsion will be perpetuated by “W” sitting (sitting on knees with the feet outside the thighs, promoting internal rotation of the femur)

  • Femoral antetorsion will be perpetuated by sitting cross legged, which forces the thigh into external rotation.

 

Stay tuned for a case tomorrow to test your learning over the last few weeks.

 

We remain: Bald, good looking and intelligent…The Gait Guys

 

 

All material copyright 2013 The Gait Guys/ The Homunculus Group. All rights reserved.  Please ask to use our stuff!

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Yes, we are all twisted. Part 3 continued.

If you missed yesterdays post, this one will make more sense if you go back and read it.Today we talk about compensations for tibial torsions.

As discussed in previous posts, there are at least 3 reasons we need to understand  tibial torsions and versions:

1. They will often alter the progression angle of gait.  In internal tibial torsion, there will often be a decreased progression angle of the foot and with external, an increased angle of progression. A decreased progression angle is often associated with a decreased step width whereas an increased angle is often associated with an increased step width.

2. They affect available ranges of motion (ROM) of the limb. We remember that the lower leg needs to internally rotate the requisite 4-6 degrees from initial contact to midstance:

ROM changes that may occur with internal tibial torsion

  • If it is already fully internally rotated (as it may be with internal tibial torsion), that range of motion must be created or compensated for elsewhere.
  • This can result in external rotation of the affected lower limb to create the range of motion neede
  • Circumduction of the lower limb, because the foot is already in a supinated posture, and the decreased range of motion of the foot needs to be compensated for.
  • A shortened step length, due to increased compressive forces at the medial knee
  • And alteration of vertical and medial lateral ground reactive forces
  • A rolling off the lateral aspect of the foot, due to it being in a more supinated posture

ROM changes that may occur with external tibial torsion          

  • external tibial torsion often results in the increased midfoot pronation, through the deformity, because more range of motion is possible both at the hip and foot at the subtalar joint

3. They often can effect the coronal plane orientation of the lower limb.

In internal tibial torsion, due to the foot being more rigid and the deformity often being accompanied by increased tibial varum, the knee often falls outside the plane of the foot (rather than being “stacked”), resulting in a decreased step width and often a cross over gait pattern (click here for more info on crossover)

In external tibial torsion, the foot is often more pliable. This often results in an increased step width and well as the knee falling inside (or medially) to the plane of the foot. Because of the increased hip and foot ranges of motion available,  the foot is not an adequate lever, shortening step length and sometimes requiring increased pelvic motion to “get around” the stance phase leg.

Whew! This stuff can be tough, Thanks for hanging in there! Next stop: Femoral Torsions and Versions!

Ivo and Shawn; your torsioned friends : )

 

All material copyright 2013 The Gait Guys/ The Homunculus Group. All rights reserved.  Ask before you lift our stuff, Lee is watching……

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We’ve got an angle….. The Progression Angle

1st of a non sequential series

The progression angle is the angle to foot makes with the ground at initial contact of gait to loading response, and it is often carried through the gait cycle to toe off (see left image above). It is something we often look at to see how a patient may be compensating. It often represents how forces are traveling through the foot (see right image above).

The normal line of force through the foot during a gait cycle should begin at the lateral aspect of the heel, travel up the lateral column of the foot, across the metatarsal heads from the 5th to the 1st, and then through the hallux (see L part of right picture above.

We remember that the foot strikes the ground in a supinated posture, then pronates from initial contact through the middle of midstance (to provide shock absorption and initiate medial spin of the lower extremity: see picture bottom left); the foot should then supinate, to make the foot into a rigid lever, with this being initiated by the opposite limb going into swing and externally rotating the stance phase lower extremity (se picture bottom right)

The progression angle is determined by many factors, both anatomical and functional, and is often a blend of the 2.

Anatomical factors include:

  • subtalar joint positioning
  • tibial torsion
  • femoral torsion
  • acetabular dysplasia

and functional causes can include:

  • compensation for a hallux limitus or rigidus
  • weak glutes (of course we wouldn’t leave our favorite muscle out)
  • loss of ankle rocker
  • over or under pronation
  • and the list goes on….

Next time we begin breaking this down into bite sized chunks to aid digestion.

Ivo and Shawn. Bald. Good Looking. Middle Aged. Definitive Foot and Gait Geeks : )

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This week we will focus on the basics of gait and the gait cycle in our attempt to assist in gait literacy

Gait Cycle Basics: Part 1

Steps and strides….

What does the gait cycle that have to do with therapy or rehabilitation? Well, most people walk at some point in the day, and most have walked into your office. If people can’t carry the changes you made on the table and incorporate it into walking, then what you do will have limited effectiveness. Thus, the need for understanding the gait cycle as it relates to rehabilitation or how it can give you clues to the biomechanical faults present. An example is a loss of functional hip extension and chronic LBP/ SI dysfunction. This could be due to a myriad of reasons, from weak glutes, loss of ankle dorsiflexion, or even a dysfunctional shoulder. Understanding how these seemingly unrelated body parts integrate into the kinetic chain, especially while moving upright through the gravitational plane.

 

One gait cycle consists of the events from heel strike to heel strike on one side. A step length is the distance traveled from one heel strike to the next (on the opposite side). Comparing right to left step lengths can give the evaluator insight into the symmetry of the gait.  Differences in step length, on the simplest level, should cause the individual to deviate consistently from a straight line (technically it should cause the individual to eventually walk in a large circle!).  Often, compensations occur functionally in the lower kinetic chain to compensate for the differences in step length to ensure that you walk in a straight line.  It is these longstanding complex compensations that are the generators of many of our patient’s complaints.

 

A stride length is the distance from heel strike to heel strike on the ipsilateral side (the distance covered in one gait cycle.  Step width, or base of gait, is the lateral distance between the heel centers of two consecutive foot contacts (this typically measures 6-10 cm).  Foot progression angle is the angle of deviation of the long axis of the foot from the line of progression (typically 7-10 degrees). Çhanges in the progression angle can be due to both congenital (torsions, versions) as well as developmental reasons.

Next time we will take a closer look at the gait cycle itself. Yup, we are still…The Gait Guys

special thanks to Dr. Tom Michaud, who has allowed us to use these images in our book