“. . . according to the Yoga Sutra (3.1), the term [Bandha] refers to the ‘binding’ of consciousness to a particular object or locus (desha), which is the very essence of concentration.”
Georg Feuerstein

Monday, March 10, 2014

Refining the Pelvis in Warrior I

Yoga often happens in millimeters. This means that relatively small adjustments can produce some of the most important openings and energetic shifts. In this blog post, I describe a cue to refine the pelvis in the asana, Warrior I (Virabhadrasana I), concluding with a brief discussion of the biomechanics of this adjustment.

Here’s the cue...

In Warrior I, press the back foot into the mat and attempt to drag it toward the midline (adduction). You will feel the pelvis turn forward to “square” with the front leg. Figures 1 and 2 illustrate this action, with its effect on the pelvis.


Figure 1: Press the foot into the mat and then attempt to drag it toward the midline. This engages the adductor magnus.

Here are the biomechanics of this cue...

In Warrior I, the back leg is in extension. The prime mover muscle for this action is the gluteus maximus. One of the synergists for extending the hip is the adductor magnus muscle. Attempting to drag the foot towards the midline engages this muscle in the pose. The foot remains constrained on the mat and does not actually move, however, the force of contracting the adductor magnus decreases the angle between the femur and the pelvis, as shown. The result is that the pelvis turns (instead of the foot moving). In addition, the hip extends more effectively. All of this produces a unique opening in the front of the pelvis that stretches the hip flexors, including the psoas muscle (figure 3).


Figure 2: This illustrates engaging the adductor magnus by attempting to drag the foot towards the midline. The mat constrains the foot, and the force of contraction turns the pelvis.


Figure 3: This illustrates the flexor muscles of the back hip stretching.

Use this adjustment after “setting” the feet. The technique for this is described in my previous blog post on connecting to your feet in yoga. Click here to read more. These cues can be combined with co-activation of the hip stabilizers for the front leg, as described previously for Warrior II (click here to read more). Finally, “ease into” your movements when working with cues such as this. Build muscular engagement gradually to turn the pelvis; then gradually release it as you come out of the pose.

For many more helpful cues on biomechanics and yoga, feel free to browse through "The Key Muscles and Key Poses of Yoga". Also, see the "Yoga Mat Companion" series, which gives you step-by-step guidelines for applying these cues to all categories of poses. Click here to learn more.


Namaste’

Ray and Chris (illustrator)


Tuesday, December 24, 2013

Healing with Yoga: Piriformis Syndrome

Years ago I developed sciatica as a consequence of a martial arts injury. I had seen a number of doctors who finally diagnosed it as an entrapment syndrome involving the piriformis muscle and the sciatic nerve. I tried, unsuccessfully, all of the conservative methods to treat it, including physical therapy, massage, manipulation—you name it. Finally, it looked like I would either have to live with the pain or have surgery—for which there was no guarantee of success. As it happened, one day I wandered into a yoga class at the Ann Arbor YMCA.

I remember being impressed by how different (and difficult) a yoga class was, even though I was used to hard physical training from playing sports; we were working with the body in ways I had never experienced and using precise movements and muscular engagements I hadn’t seen in other exercise methods. Not only did I feel great after my first class but also, to my surprise, the next day I noticed that my sciatic pain was greatly improved. Putting two and two together, I started going regularly to classes at YMCA (and later, the basement of a church). As long as I went to class, my sciatica no longer bothered me. With this in mind, let’s take a look at piriformis syndrome.

Piriformis Syndrome:

Piriformis syndrome is characterized by buttock and/or hip pain that may radiate into the leg as a form of sciatica. This syndrome is thought to result from spasm of the piriformis which causes irritation of the sciatic nerve as it passes across (or through) the muscle. Spasm in the piriformis can be precipitated by an athletic injury or other trauma. The mainstay of treatment involves stretching the piriformis and its neighboring external hip rotators, with surgery to release the muscle reserved for recalcitrant cases.

Tightness or asymmetries in the piriformis muscle can create rotational pelvic imbalances. This, in turn, can lead to imbalances further up the spinal column, through the process of "joint rhythm". Click here to learn more about lumbar pelvic rhythm in our previous blog post on Preventative Strategies for Lower Back Strains. Below in the links is a reference to an article from the Osteopathic literature addressing this subject in relation to the piriformis muscle.

Figure 1 is an illustration of the relationship of the sciatic nerve to the piriformis muscle. Approximately 80% of the time the nerve passes anterior to the muscle, exiting below the piriformis. The sciatic nerve can also divide above the muscle, with one branch passing through the piriformis and another branch passing anterior. This variation occurs about 14% of the time. Other variations include the undivided nerve passing through the muscle and the divisions passing both anterior and posterior to the piriformis (without penetrating the muscle). Note that the sciatic nerve can penetrate the muscle without ever causing pain or other symptoms (as is usually the case). Persons with this variation may, however, be predisposed to developing piriformis syndrome from an injury.

Various relationships of the sciatic nerve to the piriformis muscle.

Diagnosis of piriformis syndrome is accomplished through a careful history and physical examination as well as radiological studies. The physical exam includes the FAIR test (flexion, adduction, internal rotation of the hip). Click here for an example of this test.

Note that other causes of sciatica must be excluded before making the final diagnosis of piriformis syndrome. These include a herniated disc causing nerve root compression. Similarly, pathology affecting the hip joint must also be excluded. Accordingly, if you have sciatic type pain, be sure to consult a health care practitioner who is appropriately trained and qualified to diagnose and manage such conditions.

To review, when the hip is in a neutral position, the piriformis acts to externally rotate (turn outward), flex and abduct the hip joint. When the hip is flexed beyond about 60 degrees the piriformis becomes an internal rotator and extensor (and remains an abductor). Muscles stretch when we move a joint in the opposite direction of the action of the muscle. Click here for a review of the piriformis muscle, its attachments and action, and the mechanism of Reverse Pigeon Pose (video below).

Figures 2-5 illustrate several yoga poses that stretch the piriformis. Parvritta trikonasana and the rotating version of Supta padangustasana lengthen the muscle by adducting and flexing the hip. Similarly, Parsva bakasana and Marichyasana III adduct and flex the hip joint, thus stretching the muscle (which an extensor and abductor when the hip is flexing).

Figure 2. Piriformis stretching in supta padangusthasana.

Figure 3. Piriformis stretching in Parvritta trikonasana.

Figure 4. Piriformis stretching in Marichyasana III.

Figure 5. Piriformis stretching in Parsva bakasana.

Figure 6. Supported setu bandha - a recovery pose which maintains the piriformis in a relaxed position.

Video 1 demonstrates stretching of the piriformis in Reverse Pigeon Pose. This asana stretches the muscle by externally rotating and flexing the hip.



Video 2 illustrates the technique for using mysofascial connections to protect the knee joint in this pose. Click here for the details of this technique.



Thanks for stopping by. If you would like to learn more about combining modern Western science and yoga, feel free to browse through The Key Muscles and Key Poses of Yoga, as well as the Yoga Mat Companion series by clicking here. For a fun, yet intensive experience in anatomy, biomechanics and therapeutics of yoga, join us for our five-day intensive in Bali. Click here for more info and to register. Happy Holidays and many thanks for your support in sharing us on Facebook, Twitter and Google Plus!


Namaste'


Ray and Chris (illustrations)


References:
  1. Pokorný D, Jahoda D, Veigl D, Pinskerová V, Sosna A. “Topographic variations of the relationship of the sciatic nerve and the piriformis muscle and its relevance to palsy after total hip arthroplasty.” Surg Radiol Anat. 2006 Mar;28(1):88-91.

  2. Boyajian-O'Neill LA, McClain RL, Coleman MK, Thomas PP “Diagnosis and management of piriformis syndrome: an osteopathic approach.” J Am Osteopath Assoc. 2008 Nov;108(11):657-64.

  3. Filler AG, Haynes J, Jordan SE, Prager J, Villablanca JP, Farahani K, McBride DQ, Tsuruda JS, Morisoli B, Batzdorf U, Johnson JP. “Sciatica of nondisc origin and piriformis syndrome: diagnosis by magnetic resonance neurography and interventional magnetic resonance imaging with outcome study of resulting treatment.” J Neurosurg Spine. 2005 Feb;2(2):99-115.
  4. Rodrigue T, Hardy RW. “Diagnosis and treatment of piriformis syndrome.” Neurosurg Clin N Am. 2001 Apr;12(2):311-9.

  5. Papadopoulos EC, Khan SN. “Piriformis syndrome and low back pain: a new classification and review of the literature.” Orthop Clin North Am. 2004 Jan;35(1):65-71.

Friday, December 13, 2013

Preventing Yoga Injuries vs Preventing Yoga, Part III: Joint Mobility, Stability and Proprioception

A central concept in all healing arts is that of correcting imbalances within the body. The principle of re-establishing balance can be found across all cultures from Navajo sand paintings, Ayurveda, Traditional Chinese Medicine to modern allopathy.  And anything with true healing power also has the capacity to cause injury when practiced without balance. For example, joint mobility is beneficial for a number of reasons--provided it is balanced with joint stability. In this blog post I discuss the concept of joint proprioception and its relationship to joint stability and yoga, concluding with a tip for “re-setting” muscular proprioception following hip openers. 

Proprioception refers to the sense of the relative position of neighboring body parts, such as the femoral head within the hip socket (acetabulum) as well as the muscular force utilized in movement of those parts. This is in contradistinction to exteroception, which is the perception of the outside world (like the feeling of the feet on the ground) and interoception, which is the perception of the inside of the body (pain, hunger etc). I look at proprioception as a type of “GPS” for the joints.

Joint position is detected by specialized nerve endings known as “proprioceptors” that are located within the muscles, ligaments and joint capsule and the periosteum (on the surface of the bones). These receptors communicate information about the joints to the brain via the sensory columns of the spinal cord.  Conscious sense of joint position is transmitted to the cerebrum of the brain; unconscious proprioception is communicated to the cerebellum. Figure 1 illustrates this pathway in a cross section of the spinal cord. 





Scientific studies have demonstrated that joint position sense is decreased in persons with osteoarthritis, with the consideration that reduced proprioception may play a role in the development of the disease. Indeed, exercises that improve proprioception have been demonstrated to be effective in the conservative management of osteoarthritis.  

Proprioception is also reduced in persons with joint hypermobility; exercises that improve joint position sense are also effective in reducing symptoms in this population. I suspect that proprioception may be also be a factor in those having joint pain associated with subtle instability (who do not have an identifiable cause for their pain such as arthritis, hypermobility or a structural lesion). Similarly, the diminished performance seen in certain athletes following stretching routines may be related to reduced joint position sense.

I bring this up in relation to yoga because certain individuals experience soreness in their hips following hip opening poses.  Understanding that this pain may be related to decreased proprioception, I have been using a simple technique to re-establish joint position sense following these poses. For example, I worked with several practitioners during the Blue Spirit Intensive who had this type of hip soreness. Following a sequence that led to Full Lotus, we applied the technique, which “resets” the joint position sense in the hips. After the “reset”, these folks noticed that the hip pain they typically felt was gone, with this benefit remaining throughout the day.

This leads me to believe that some of the hip pain experienced by practitioners may be related to a reduction in muscular proprioception after stretching, which persists as a subtle form of instability during other activities following practice. Furthermore, the soreness appears to be relieved by a technique to increase proprioception that involves co-activating the muscles surrounding the hip joint at a midpoint of the joint's range of motion.

Here’s the technique…

Following a hip opening sequence, and before Savasana, I utilize an intermediate version of Warrior II, where the forward knee and hip are not flexing deeply (figure 2). Then I “co-activate” the hip muscles in the forward leg (co-activation involves simultaneously contracting muscles that have opposite actions). The cue for this is to imagine pressing the inside of knee into an immoveable object while at the same time pressing the outside of the knee into a similar object (the knee remains centered and does not move). This engages both the hip adductors and abductors, as well as the internal and external rotators in a position where the joint is in the mid-range of motion. Done properly, this cue should give a feeling of stability in the hip joint.

Since it is a neurological process, this technique does not require strong muscular contraction; I only utilize just enough strength to feel the muscles engage and the hip stabilize. Furthermore, the cue only requires a short duration. I have been using 20 seconds, repeated twice on each side. The effect is a bit like “resetting” a GPS that has gone out of its normal range. Figures 3-5 illustrate the muscle groups involved with the arrows demonstrating the direction of force. Visualization of the muscles helps in this process.

Figure 2: Warrior II intermediate version. I use this for training proprioception.

Figure 3: Co-activating the hip adductors, abductors and rotators in Warrior  II.

Figure 4: Co-activating the hip adductors, abductors and rotators in Warrior  II.

Figure 5: Activating the deep external rotators of the hip in Warrior II.


Thanks for stopping by. We hope that you enjoy this tip on training proprioception of the hip joint. Note that if you have persistent hip pain or other symptoms, be sure to consult a health care provider who is appropriately trained and qualified to manage such conditions. 

If you would like to learn more about anatomy, biomechanics and yoga, feel free to browse through The Key Muscles and Key Poses of Yoga. Also, check out the Yoga Mat Companion series, which contains many examples of co-activation (including the one in this post). Many thanks for your support by sharing us on Facebook, Twitter and Google Plus as well.

Namaste'

Ray and Chris



References:
  1. Wolf JM, Cameron KL, Owens BD. “Impact of joint laxity and hypermobility on the musculoskeletal system.” J Am Acad Orthop Surg. 2011 Aug;19(8):463-71.
  2. Smith TO, Jerman E, Easton V, Bacon H, Armon K, Poland F, Macgregor AJ. “Do people with benign joint hypermobility syndrome (BJHS) have reduced joint proprioception? A systematic review and meta-analysis.” Rheumatol Int. 2013 Nov;33(11):2709-16.
  3. Smith TO, King JJ, Hing CB. “The effectiveness of proprioceptive-based exercise for osteoarthritis of the knee: a systematic review and meta-analysis.” Rheumatol Int. 2012 Nov;32(11):3339-51.
  4. Sahin N, Baskent A, Cakmak A, Salli A, Ugurlu H, Berker E. “Evaluation of knee proprioception and effects of proprioception exercise in patients with benign joint hypermobility syndrome.” Rheumatol Int. 2008 Aug;28(10):995-1000.
  5. Lund H, Juul-Kristensen B, Hansen K, Christensen R, Christensen H, Danneskiold-Samsoe B, Bliddal H. “Movement detection impaired in patients with knee osteoarthritis compared to healthy controls: a cross-sectional case-control study.” J Musculoskelet Neuronal Interact. 2008 Oct-Dec;8(4):391-400.
  6. Sharma L. “Proprioceptive impairment in knee osteoarthritis.” Rheum Dis Clin North Am. 1999 May;25(2):299-314, vi.
  7. Liikavainio T, Lyytinen T, Tyrväinen E, Sipilä S, Arokoski JP. “Physical function and properties of quadriceps femoris muscle in men with knee osteoarthritis.” Arch Phys Med Rehabil. 2008 Nov;89(11):2185-94.
  8. Lauersen JB, Bertelsen DM, Andersen LB. “The effectiveness of exercise interventions to prevent sports injuries: a systematic review and meta-analysis of randomised controlled trials.” Br J Sports Med. 2013 Oct 7.
  9. Caplan N, Rogers R, Parr MK, Hayes PR. “The effect of proprioceptive neuromuscular facilitation and static stretch training on running mechanics.” J Strength Cond Res. 2009 Jul;23(4):1175-80.
  10. Higgs F, Winter SL. “The effect of a four-week proprioceptive neuromuscular facilitation stretching program on isokinetic torque production.” J Strength Cond Res. 2009 Aug;23(5):1442-7.
  11. Handrakis JP, Southard VN, Abreu JM, Aloisa M, Doyen MR, Echevarria LM, Hwang H, Samuels C, Venegas SA, Douris PC. “Static stretching does not impair performance in active middle-aged adults.” J Strength Cond Res. 2010 Mar;24(3):825-30.
  12. Wu Q, Henry JL. “Functional changes in muscle afferent neurones in an osteoarthritis model: implications for impaired proprioceptive performance.” PLoS One. 2012;7(5): Epub 2012 May 14.
  13. Shu B, Safran MR. “Hip instability: anatomic and clinical considerations of traumatic and atraumatic instability.” Clin Sports Med. 2011 Apr;30(2):349-67.
  14. Smith MV, Sekiya JK. “Hip instability.” Sports Med Arthrosc. 2010 Jun;18(2):108-12.
  15. Holla JF, van der Leeden M, Peter WF, Roorda LD, van der Esch M, Lems WF, Gerritsen M, Voorneman RE, Steultjens MP, Dekker J. “Proprioception, laxity, muscle strength and activity limitations in early symptomatic knee osteoarthritis: results from the CHECK cohort.” J Rehabil Med. 2012 Oct;44(10):862-8.

Tuesday, November 19, 2013

Preventing Yoga Injuries vs Preventing Yoga, Part II: Joint Hypermobility

In this post we discuss labral tears and the condition of joint hypermobility. I also present the case of a specific injury from yoga practice, its biomechanical basis and the steps that can be taken to aid in its prevention.

First, however, let’s look at the concept of association vs causality. Simply put, because some activity is associated with a problem does not mean it caused it. In medicine, when we recognize that an injury is associated with a specific activity we then investigate whether there are factors associated with that activity that could cause the injury. An example would be anterior cruciate ligament (ACL) tears.

A while back, we recognized that ACL tears were approximately five times more common in female athletes compared to males. Thus, investigators sought to identify circumstances that could account for this increased incidence. The risk factor thought to contribute most significantly to the higher rate of ACL ruptures in female athletes related to insufficient neuromuscular control of the knee joint in certain athletes. Accordingly, neuromuscular training regimens were devised that have reduced the incidence of ACL ruptures in this group. This approach to ACL injuries is an example of working with science to decrease the risk of an activity, not the activity itself. With this in mind, let’s look at the potential association of joint hypermobility with yoga injuries.

Joint hypermobility, also known as generalized ligamentous laxity, is a spectrum ranging from mild “loose joints” to systemic pathological conditions such as Ehlers Danlos syndrome (a rare inherited condition that affects the connective tissue throughout the body). “Benign” joint hypermobility, or “double jointedness”, affects between 5% and 15% of the population, with most studies showing this condition to be significantly more common in women vs men. We evaluate the degree of hypermobility using the Beighton criteria, which examines factors such as knee, elbow and thumb hyperextension. Based on these factors, a score is created to quantify whether a person has hypermobility syndrome.

Joint hypermobility affects the capsular and ligamentous stabilizers of the articulations, which are lax. It is associated with an increased incidence of musculoskeletal injuries, including to the labrum of the shoulder and hip joints due to increased translations across the structure. The mainstay of management for ligamentous laxity (hypermobile joints) is physical therapy that is focused on strengthening the muscular stabilizers surrounding a given joint and improving proprioception. Now, let’s look at joint hypermobility in relation to injuries that may be associated with yoga.

Injuries that can be unequivocally directly attributed to practicing yoga, like the one described below, are infrequent (in my clinical experience) simply because yoga practitioners are active people who engage in other pursuits that may also cause injuries (sports, dance etc). Put another way, folks that actually practice yoga are generally not couch potatoes. Further complicating the issue are age related disease processes that can affect the joints whether or not one practices yoga. Nevertheless, we need to watch for associations of injuries with yoga and, where possible, determine their underlying cause, identify subgroups that may be at particular risk, and take steps to minimize those risks. With this in mind, let’s look at a specific injury that was caused during yoga practice, its biomechanical basis and steps that can be taken to aid in prevention.

During the past year I saw one yoga injury that was specifically caused by practicing a pose. This involved an experienced teacher who was demonstrating the “wrong way” to perform Vasisthasana (side plank pose) by having the hand of the supporting arm forward of the shoulder joint instead of directly below the shoulder and at a right angle to the floor. In the process, she experienced a “clunk” in her shoulder, followed by pain. On exam in the clinic, she was found to have joint hypermobility, as quantified by the Beighton criteria. Her MRI demonstrated a tear of the posterior part of the shoulder labrum. Conservative treatment with physical therapy, etc. was not successful in relieving her pain and she required arthroscopic repair of the labrum with tightening of the capsule.

It is worth noting that this teacher had practiced Vasisthasana many times with the hand placed below the shoulder without difficulty. Additionally, on questioning it was clear that she was not actively engaging the muscular stabilizers of the shoulder joint during the demonstration.

Now, let’s look at the mechanism of injury. First, as part of their joint hypermobility, this person had a condition known as “multidirectional shoulder instability”. In patients with this condition, the shoulder capsule and ligaments are lax and thus, do not contribute sufficiently to stability of the joint. As a result, the head of the shoulder can “slide” around on the glenoid (socket) more than usual. This causes increased translational forces across the glenoid labrum. In this particular case, while attempting side plank, she subluxed the head of the humerus over the labrum, tearing it.


Figure 1: Bone structure of the shoulder; Figure 2: Ligaments and capsule; Figure 3: Muscular stabilizers
1-supraspinatus, 2-subscapularis, 3-infraspinatus, 4-triceps, 5-biceps(short head),
6-biceps(long head), 7-deltoid, 8- pectoralis major, 9-pectoralis minor

The three factors that contribute to mobility and stability of the joint are the bone shape, the capsulo-ligamentous structures and the muscles surrounding the articulation. Figure 1 illustrates the structure of the shoulder joint. Composed of a shallow socket and relatively thin capsular and ligamentous supports, this is the most mobile articulation in the body. The muscular stabilizers, including the rotator cuff play an important role in maintaining the congruency of the shoulder joint. When the capsule and ligaments are loose, then the muscles must compensate. This is why we focus on strengthening the muscles in multidirectional shoulder instability. Figures 1, 2 and 3 illustrate the bone structure, capsulo-ligamentous stabilizers and muscular stabilizers respectively.
Figure 4: Vasisthasana illustrating the direction of gravity in variations of hand position.

Looking at the factors that caused this teacher to experience a subluxation with the hand forward of the shoulder we can see that, in this position, the body weight is directed at an angle to the alignment of the arm bones. When the hand is placed below the shoulder, the supporting arm is aligned in a position such that the bones are perpendicular to the direction of gravity. Practicing the pose in this way requires less muscular effort because it uses the inherent passive strength of the bones to aid in supporting the body weight. When the hand is placed forward of the shoulder, greater muscular effort is required to maintain the pose (figure 4).

People with joint hypermobility depend to a greater degree on the muscular stabilizers of the joint. Placing the hand so that the arm is angled against gravity means that these muscles must also work to support the body weight that would be borne, in part, by the bones. You can experience this concept yourself by standing near a wall and leaning against it (figure 5). Then, move the feet a bit further from the wall. Which one requires less muscular effort?

Figure 5: Illustrating using bone alignment vs muscular force.

Figures 6 illustrates Vasisthasana with the supporting muscular stabilizers. I go over a step-wise approach to engaging these muscles and the other core stabilizers of the trunk and legs in Yoga Mat Companion Four (arm balances and inversions).

Figure 6: Muscular stabilizers of the shoulder in Vasisthasana.

Labral Tears in the Hip:

In our most recent blog post we discussed the normal structure and function of the hip labrum. Now let’s discuss labral tears. A number of activities have been associated with this injury including soccer, hockey, golf, ballet, gymnastics, and running. Additionally, a number of specific movements have been associated with labral tears. Pregnancy and childbirth have also been associated with acute tears of the labrum. Even shopping has been associated with injuries to this structure ("supermarket hip"). Other causes of labral tears include ligamentous laxity and abnormalities of the bone. Nevertheless, up to 75% of the time, symptomatic labral tears of the hip are not associated with an identifiable event or cause.

Adding to the complexity is the consideration that labral pathology may be related to the aging process, with up to 96% of cadaver specimens having tears. Furthermore, labral tears do not always cause pain; indeed, a prospective blinded study published in the American Journal of Sports Medicine identified labral tears in 69% of the joints studied in volunteers with no history of injury, pain or other symptoms. Even accounting for false positive mri’s, that is a significant number. Hip injuries and arthritis are among the most intensively investigated areas in medicine today, with new studies being published each month. In this regard, please review the linked references below.

Figure 7: Hip Labral Tear.

One of the known causes of tears of the hip labrum is joint hypermobility. This is also a factor during pregnancy, when hormonal influences cause ligamentous laxity in persons who are not normally hypermobile. Tears of the hip labrum occur in this setting as result of increased translational forces across the labrum from the femoral head. As with hypermobile joints elsewhere in the body, hypermobility in the hips is managed (at least initially) by strengthening the muscular stabilizers that surround the joint. This aids to prevent injuries.

I think this is relevant in light of recent media attention on hip injuries and yoga, particularly since many of those practicing poses that take the hip joints into extreme positions also have hypermobile joints. In my experience, such individuals—who can easily perform extreme movements—often do so without maintaining muscular engagement during extremes of motion. Of particular note is a recent NY Times article that discusses flexibility as a liability for women in yoga. While spending considerable time discussing bone abnormalities (which are more prevalent in men, and were not thought to be a factor in studies on dancers), the NY Times article does not discuss joint hypermobility or the use of muscular stabilization during practice--something that is a cornerstone of injury prevention, especially in persons with high levels of joint mobility. Perhaps a more relevant view of the matter was presented in the Canadian media

Finally, here are a couple of suggestions that I have found to be helpful in my own practice and teaching:

  1. Ease into the end points of poses. Joints adapt to gradual changes much better than abrupt or rapid ones. For example, I deliberately slow down my movement as I near the end point of forward flexion in Uttanasana. This helps to protect the joints and also creates mindfulness in the practice.
  2. Use gentle muscular engagement to stabilize the joints. This is a cornerstone of rehabilitation and injury prevention. Knowledge of the musculoskeletal system and visualization helps in this process.

Note: if you have hip pain or other symptoms (from any activity), be sure to consult a health care professional who is appropriately trained and qualified to diagnose and manage such conditions. Follow their guidelines for your condition.

To learn more about anatomy, biomechanics and yoga, feel free to page through The Key Muscles and Key Poses of Yoga and the Yoga Mat Companion Series. If you would like to learn more about combining modern Western science with the ancient art of yoga, please join us for a week in paradise at our workshop in Bali for a five day intensive on anatomy, biomechanics and therapeutics for Hatha yoga.

Thanks for stopping by. Be sure to tune in this week for our next post. Also, many thanks for your support by sharing us on Facebook, Twitter and Google Plus.

Namaste',

Ray and Chris

References:
  1. Mandelbaum BR, Silvers HJ, Watanabe DS, Knarr JF, Thomas SD, Griffin LY, Kirkendall DT, Garrett W Jr. “Effectiveness of a neuromuscular and proprioceptive training program in preventing anterior cruciate ligament injuries in female athletes: 2-year follow-up.” Am J Sports Med. 2005 Jul;33(7):1003-10.
  2. Wolf JM, Cameron KL, Owens BD. “Impact of joint laxity and hypermobility on the musculoskeletal system.” J Am Acad Orthop Surg. 2011 Aug;19(8):463-71.
  3. Pacey V, Nicholson LL, Adams RD, Munn J, Munns CF. “Generalized joint hypermobility and risk of lower limb joint injury during sport: a systematic review with meta-analysis.Am J Sports Med. 2010 Jul;38(7):1487-97.
  4. Konopinski MD, Jones GJ, Johnson MI. “The effect of hypermobility on the incidence of injuries in elite-level professional soccer players: a cohort study.Am J Sports Med. 2012 Apr;40(4):763-9.
  5. McCormack M, Briggs J, Hakim A, Grahame RJoint laxity and the benign joint hypermobility syndrome in student and professional ballet dancers.J Rheumatol. 2004 Jan;31(1):173-8.
  6. Boykin RE, Anz AW, Bushnell BD, Kocher MS, Stubbs AJ, Philippon MJ. “Hip instability. J Am Acad Orthop Surg. 2011 Jun;19(6):340-9.
  7. Lewis CL, Sahrmann SA. “Acetabular labral tears. Phys Ther. 2006 Jan;86(1):110-21.
  8. Groh MM, Herrera J. “A comprehensive review of hip labral tears. Curr Rev Musculoskelet Med. 2009 Jun;2(2):105-17.
  9. Baker JF, McGuire CM, Mulhall KJ.Acetabular labral tears following pregnancy. Acta Orthop Belg. 2010 Jun;76(3):325-8.
  10. Yamamoto Y, Villar RN, Papavasileiou A. “Supermarket hip: an unusual cause of injury to the hip joint.Arthroscopy. 2008 Apr;24(4):490-3
  11. Register B, Pennock AT, Ho CP, Strickland CD, Lawand A, Philippon MJ. “Prevalence of abnormal hip findings in asymptomatic participants: a prospective, blinded study.Am J Sports Med. 2012 Dec;40(12):2720-4.
  12. Agricola R, Heijboer MP, Roze RH, Reijman M, Bierma-Zeinstra SM, Verhaar JA, Weinans H, Waarsing JH. Pincer deformity does not lead to osteoarthritis of the hip whereas acetabular dysplasia does: acetabular coverage and development of osteoarthritis in a nationwide prospective cohort study (CHECK).Osteoarthritis Cartilage. 2013 Oct;21(10):1514-21.
  13. Leunig M, Jüni P, Werlen S, Limacher A, Nüesch E, Pfirrmann CW, Trelle S, Odermatt A, Hofstetter W, Ganz R, Reichenbach S. “Prevalence of cam and pincer-type deformities on hip MRI in an asymptomatic young Swiss female population: a cross-sectional study.Osteoarthritis Cartilage. 2013 Apr;21(4):544-50.
  14. Agricola R, Heijboer MP, Bierma-Zeinstra SM, Verhaar JA, Weinans H, Waarsing JH. “Cam impingement causes osteoarthritis of the hip: a nationwide prospective cohort study (CHECK).Ann Rheum Dis. 2013 Jun;72(6):918-23.
  15. Charbonnier CKolo FCDuthon VBMagnenat-Thalmann NBecker CDHoffmeyer PMenetrey J. Assessment of congruence and impingement of the hip joint in professional ballet dancers: a motion capture study. Am J Sports Med. 2011 Mar;39(3):557-66.



Friday, November 15, 2013

Preventing Yoga Injuries vs Preventing Yoga, Part I: The Hip Labrum

I’m thinking the ancients were onto something. Meaning this (possibly) 5,000 year old art that so many of us enjoy practicing and teaching. I’m talking about the tradition of Hatha yoga. The one that includes putting our bodies into poses like Uttanasana, Dandasana, Padmasana (Full Lotus), Sirsasana (Headstand) etc. Now, part of that practice involves poses that take some of our joints to the extremes of their range of motion (from a western medical perspective). Indeed, many of the benefits of Hatha yoga derive from moving our joints (carefully) within their range of motion.

Obviously, we want to avoid injuries when practicing yoga. One way to do that is to eliminate a bunch of the asanas on the grounds that they’re “too dangerous”. That approach also eliminates the benefits of those poses. Or, we can practice mindfully, using modifications where appropriate and working in a progressive manner towards the classical asanas that are appropriate for each of us individually. Knowledge of the body combined with awareness of mechanisms of injury aids in this process.

In medicine, we look for ways to eliminate the risks of a given activity, not the activity itself. To illustrate my point, check out this quote from one of the scientific articles that studied the effect of extreme hip motion in professional ballerinas:

These results do not mean that the dancers should stop executing these movements, but rather they should limit them in frequency during dancing class.”2

Wow. Think I’m down with that.

You mean we don’t have to toss out Developpe Devant, Developpe a la Seconde, Grand Ecart Facial and Grand Ecart Latéral and create a new "gentler ballet"? Of course not. Because it would be kind of boring to watch a ballet that consisted of folks sitting on a stage, waving their arms around (to say nothing of the dangers to the rotator cuff). Similarly, Hatha yoga wouldn’t have its beneficial effects without, you know, the poses of Hatha yoga.

So, with this in mind, let’s review the structure of the hip, paying particular attention to the labrum.

As a general consideration, mobility and stability of the joints are determined by three factors. First, there is the shape of the bone at the joint; for example a ball and socket vs a hinge. Next there are the soft tissue stabilizers such as the ligaments, capsule, labrum or meniscus. Finally, there are the muscular stabilizers that surround a given articulation. A related subject is the concept of joint congruency. This refers the fit of opposing joint surfaces. High joint congruence means there is more surface area in contact; low joint congruence decreases the contact area.

A central tenet of rehabilitation and injury prevention relates to strengthening the muscular stabilizers of the joints. This aids to enhance congruency of the articular surfaces while at the same time providing dynamic support for the soft tissue stabilizers such as the ligaments, labrum and menisci. For example, in sports that put the soft tissue and bones at risk, we integrate training that improves proprioception and strengthens the muscles surrounding the joints.

Hip joint cross-section showing articular surface and acetabular labrum.

Let’s begin by looking at the acetabular labrum. This is a fibrocartilaginous ring-like structure that encircles the outer edge of the socket of the hip joint. Like the meniscus of the knee and the labrum of the shoulder, the hip labrum deepens the joint and contributes to its stability, while aiding in pressure distribution along the articular cartilage. It also acts as a type of seal that helps to retain the synovial fluid within the joint itself, thus allowing for some of the load on the joint to be borne by fluid pressurization, while at the same time helping with joint lubrication.

1-hip joint and labrum, 2-acetabular cartilage, labrum and ligamentum teres, 3-capsule lining showing synovium.

The labrum is relatively avascular, with blood vessels entering near the peripheral edge where it attaches to the bone and cartilage, and penetrating about one third of the way into the structure. This limits its ability to heal. Tears of the labrum are associated with hip osteoarthritis. Figures 1 and 2 illustrate the hip labrum from the outside of the joint and the acetabulum with the femur removed.

The hip is a synovial joint. These types of joints are surrounded by a capsule, which is lined by a synovial membrane (synovium) which faces the joint cavity. The synovium contains two primary cell types. The first are called fibroblasts and they secrete synovial fluid. This fluid lubricates the joint surfaces, reduces friction during movement and acts as a shock absorber through fluid pressurization. It also carries oxygen and nutrients to the articular cartilage and removes carbon dioxide. The other cell type lining the synovium is a macrophage cell; this cell removes debris or other unwanted material from the joint space. Activities that maintain joint range of motion aid in circulating the synovial fluid and bringing unwanted material into contact with the macrophages. Figure 3 (above) illustrates the joint capsule with the synovium for the hip.

1-iliofemoral ligament, 2-hip capsule, 3-pubofemoral ligament, 4-ischiofemoral ligament, 5-iliofemoral ligament.

On the outside surface of the hip capsule are the ligaments. The iliofemoral ligament runs from the anterior inferior iliac spine (AIIS) to the front and lateral part of the top of the greater trochanter of the femur. The iliofemoral ligament is the strongest ligament in the body. It functions to resist extension and external rotation of the hip and helps to prevent the pelvis from tilting backwards during standing. It also stabilizes the pelvis during the stance phase of walking, thus assisting the hip abductors. The pubofemoral ligament runs from the pubis to the neck of the femur; it prevents hyperextension and hyperabduction of the hip. The ischiofemoral ligament runs from the ischium in a spiral manner to the femoral neck. This ligament tightens in hip extension and becomes loose during flexion. The image above illustrates the hip ligaments.

Finally, there are the muscular stabilizers of the hip. I’m not going to discuss the specific actions of the individual muscles in this post. What I want to illustrate is the positions of the muscles around the joint. For example, look at the psoas and the rectus femoris muscles and how they provide an anterior support to the hip. The images below illustrate the muscular stabilizers of the hip joint.

1-iliopsoas, 2-pectineus, 3-rectus femoris, 4-sartorius, 5-gluteus medius,
6-tensor fascia lata, 7-piriformis, 8-external rotators, 9-quadratus femoris.

1-gluteus maximus, 2-tensor fascia lata, 3-adductor brevis, 4-adductor longus, 5-adductor magnus, 6-semimembranosus, 7-semitendinosus, 8-biceps femoris.

Take your time going over this material, and use the great images Chris produced to help you understand the hip joint. Stay tuned for Part II of the series, where we’ll go over some of the latest scientific research being conducted on the hip joint (research for which all of us in yoga should be extremely grateful, btw).

As always, if you have pain in your hips (from any activity), be sure to consult a health care professional who is trained and qualified to diagnose and treat such conditions.

Namaste'

Ray and Chris

References:

1. Reid DC. Prevention of hip and knee injuries in ballet dancers.” Sports Med. 1988 Nov;6(5):295-307

2. Charbonnier C, Kolo FC, Duthon VB, Magnenat-Thalmann N, Becker CD, Hoffmeyer P, Menetrey J. “Assessment of congruence and impingement of the hip joint in professional ballet dancers: a motion capture study.Am J Sports Med. 2011 Mar;39(3):557-66.

3. Gilles B, Christophe FK, Magnenat-Thalmann N, Becker CD, Duc SR, Menetrey J, Hoffmeyer P. “MRI-based assessment of hip joint translations.J Biomech. 2009 Jun 19;42(9):1201-5.

4. Mandelbaum BR, Silvers HJ, Watanabe DS, Knarr JF, Thomas SD, Griffin LY, Kirkendall DT, Garrett W Jr. Effectiveness of aneuromuscular and proprioceptive training program in preventing anterior cruciate ligament injuries in female athletes: 2-yearfollow-up.Am J Sports Med. 2005 Jul;33(7):1003-10.

Tuesday, November 5, 2013

Sankalpa, Visualization and Yoga: The Diaphragm-Psoas Connection

The Sanskrit word “Sankalpa” has been interpreted to mean a “resolution” or “intention”, usually in association with the practice of Yoga Nidra.  According to Swami Saraswati, “sankalpa has the potential to release tremendous power by clearly defining and focusing on a chosen goal.” The focus of this blog post is to illustrate the subtle, yet powerful myofascial connections between the diaphragm and iliopsoas muscle all the way down to the feet in Triangle pose. Understanding and visualizing these connections in Trikonasana will enable you to do the same in other poses.

Figure 1: Myofascial connections between the diaphragm, psoas and lower extremity.

The diaphragm, as we all know, is the central muscle of breathing. It operates mostly unconsciously, though we can consciously influence its rate and depth of contraction.  As the central muscle of breathing the diaphragm is inextricably linked to our life force and thus, our emotions and energetic body. Practicing yoga asanas influences the diaphragm in subtle ways, particularly through its connection to the psoas muscle. In fact, every pose has a slightly different effect on the diaphragm, and thus on its energetic connections. 

Figure 2: Myofascial connections between the diaphragm, psoas and lower extremity in Trikonasana.

Visualization is a powerful tool you can use to access these connections. So, before we go on to the details of anatomy and biomechanics, spend a few relaxed moments looking at figures 1 and 2, which illustrate these myofascial connections. Look at the images and then picture the connections within your body (click on the image for a larger view). Repeat this exercise two or three times, devoting five or ten seconds to each visualization. Note how you can feel the connections within yourself. Please complete this process before proceeding with the details of anatomy and biomechanics. 

And, here’s the anatomy…

The thoracic diaphragm is a dome shaped muscle that separates the chest and abdominal cavities. The contractile part of this muscle is located peripherally, inserting onto a central tendon (that is not connected to a bone). The origins of the muscle are divided into costal and lumbar portions. The “costal” portion originates from the inner surface of ribs seven through twelve. The “lumbar” portion has both medial (closer to the midline) and lateral (further from the midline) aspects. The medial aspects of the diaphragm arise from front of the first three lumbar vertebrae (L1-L3). The lateral aspects arise from three tendinous arches. The first tendinous arch is associated with the abdominal aorta, and the second and third with the psoas major and quadratus lumborum muscles respectively. Figure 3 illustrates these structures.

Figure 3: The diaphragm-psoas connection.
1) diaphragm 2) diaphragm tendon 3) aortic aperture 4) psoas arcade 5) vena caval aperture 6) esophageal aperture
Engaging the diaphragm with the glottis open expands the ribcage and produces a pressure gradient by lowering intrathoracic pressure. The negative inspiratory pressure causes air to be drawn into the lungs, thus equalizing the gradient. These fluctuating pressure gradients also facilitate blood flow, particularly venous return to the heart.

Conversely, contracting the diaphragm after exhalation with the glottis closed (as in Nauli) also produces a pressure gradient. In this case the negative inspiratory pressure draws the abdominal contents upwards (and the abdomen in). Engaging the diaphragm on exhalation with the glottis closed is a form of eccentric contraction, whereby a muscle is engaged in its lengthened state. 

Engaging the abdominals during exhalation passively stretches the diaphragm by raising the intra-abdominal pressure and lifting the abdominal organs upward against the muscle. Note that engaging the abdominals on exhalation also tensions the thoraco-lumbar fascia, which serves to stabilize the lumbar spine and sacroiliac joint. Click here for more information on this particular connection.

The psoas major muscle originates from the vertebral bodies of T12 and L1 through L4 (lateral surfaces and discs), with a deep layer originating from L1-L5 (costal processes). It combines with the iliacus muscle, which originates from the inside of the ilium (the iliac fossa) to form the iliopsoas muscle. The iliopsoas then runs over the brim of the pelvis to insert onto the lesser trochanter, a knob-like structure on the upper, inside of the femur (thigh bone). The iliopsoas crosses multiple joints and is thus considered a polyarticular muscle. When contracting on one side it can act to flex and externally rotate the femur and/or laterally flex the trunk (as in Trikonasana) or tilt one side of the pelvis forward. When the iliopsoas contracts on both sides it can flex both femurs and the trunk. Bilaterally contracting this muscle lifts the trunk from supine position (lying on the back). Figure 4 illustrates the iliopsoas muscle. Click here for a technique on isolating and awakening this important muscle to use it consciously in yoga poses.

Figure 4: The psoas.
1) psoas major 2) psoas minor 3) iliac us 4) iliopsoas (at tendon attachment to the lesser trochanter)

Now, return to the images illustrating myofascial connection between the diaphragm, the psoas and the lower extremities (figures 1 and 2). Spend a few moments in relaxed visualization of these key structures. Note how your body awareness has deepened in the brief period between now and when you first looked at them. Integrate this process into your daily practice. 

Sankalpa and creative visualization are two of the eight components of Yoga Nidra, as described by Swami Satyananda. Though typically performed during the deep relaxation phase of an asana practice, visualization and intent can be worked with during the asanas themselves. Swami Saraswati beautifully describes the process of Sankalpa as a series of stepping-stones that are used to cross a wide river. 

Our books are designed to facilitate this experience. They are based on many years of formal study of anatomy and biomechanics and use carefully designed vivid images that stimulate the visual cortex of the brain, in essence “lighting up” the muscles that are engaging in each part of the body during each pose.  In fact, many practitioners say that they can actually “feel” the muscles when looking through the Key Muscles and Key Poses of Yoga. The Yoga Mat Companion series deepens this visual experience by illustrating each pose in a step-wise fashion. This visual experience then translates to improvement in your asanas. Click here to page through all of our books.

If you would like to learn more about combining modern Western science with the ancient art of yoga, please join us for a week in paradise at Blue Spirit Costa Rica for our second annual intensive on anatomy, biomechanics and therapeutics for Hatha yoga. I will be teaching state of the art techniques on these subjects, including much new material relating to therapeutic applications of yoga--all with great 3-D illustrations, excellent food, beautiful facilities and expertly taught daily Hatha yoga classes. Although our allotment of rooms is complete, my assistant Carol will work with Blue Spirit to obtain one of the remaining rooms at the Retreat, but please contact her soon on this. 

Namaste’

Ray and Chris

Tuesday, October 29, 2013

Visualization, Biomechanics and Yoga: The Popliteus Muscle

Techniques of visualizing are employed in many disciplines. Elite athletes, from NFL quarterbacks to champion racing car drivers often integrate visualization into their training regimens. A racer will use this technique by entering a meditative state and picturing the details of the track they are going to drive, seeing every curve and bump and visualizing themselves driving a safe and flawless race. Then they go out and drive a safe and flawless race.

Visualization is also a powerful tool utilized by the medical field, particularly as an adjunct to cancer treatment. Patients relax and then picture detailed images of their immune system attacking and defeating the cancer. Indeed, visualization techniques were even utsed by my surgical training program; we were trained to conduct a mental “walk through” of the surgery we were preparing to perform, picturing each step going perfectly--with excellent results. And, as we demonstrated in our previous blog post on the piriformis muscle, an animation can be a powerful tool for integrating knowledge of the body into actual practice.

In this blog post we use visualization, combined with knowledge of function, to access one of my favorite “hidden” muscles—the popliteus. We will see how picturing the function of this muscle leads to engaging it. This engagement in turn provides additional stability for the knee in poses like Lotus, Baddha konasana and Janu sirsasana. First, let's look at the muscle itself.

Here’s the anatomy…

The popliteus muscle originates from the lateral (outside) surface of the lateral condyle of the femur (with a small slip to the lateral meniscus and fibular head) and inserts onto the inside of the back of the tibia, as shown in Figure 1. It acts to flex and internally (medially) rotate the tibia when the leg is not weight bearing and is a synergist of the medial (inside) hamstrings—the semimembranosus and semitenonosus—for these actions. It is here we will focus our attention for this blog post. The popliteus also “unlocks” the knee joint as we begin to flex it from the extended position, so strengthening this muscle can be beneficial for avoiding hyper-extending the knees. Overall, the popliteus is an important rotational stabilizer of the knee joint; engaging it enhances joint congruency. That is why I teach this cue in my workshops on Lotus pose.

Figure 1: The popliteus muscle viewed from behind the knee.

Here’s the cue…

The key to poses like Lotus, Baddhakonasana and Janu sirsasana is to obtain range of motion of the hip joint, while maintaining congruency of the knee (click here for an explanation of joint congruency). So before I practice these poses, I typically warm up with some asanas that release the muscles about the hip joint. Click here for Reverse Pigeon Pose, and here for a tip on protecting the knee in this pose.  Click here for a technique on releasing the internal rotators of the hip and here for a technique to release the hip adductors.

As a general consideration, when working on isolating smaller difficult to access muscles like the popliteus, begin with a couple of short duration visualizations. Don’t try too hard, but simply imagine the action of the popliteus in Baddha konasana as shown in Figure 2 and gently contract the muscle.  Then release and take the counter pose, Dandasana.  Repeat the process, picturing the popliteus muscle near the knee joint engaging to synergize flexing the knee and internally rotating the tibia.  Several short duration repetitions allows the brain to create circuitry to more efficiently access this important knee stabilizer. Do this process over several days, after which you will be able to engage the muscle at will and with increasing refinement.  Use gentle muscular engagement and “ease into and out of” your poses, paying attention to detail. If you experience pain in your stretch, then carefully release and come out of the pose.

Figure 2: Visualizing the popliteus muscle flexing and and internally rotating the tibia in Baddha konasana.

Muscles have evolved so that when they engage they not only move the joint but also stabilize it, maximizing joint congruency. Our books are designed to enhance the visual experience of this process for the reader. We use carefully designed vivid images that stimulate the visual cortex of the brain, in essence “lighting up” the muscles that are engaging in each part of the body during each pose.  In fact, many practitioners say that they can actually “feel” the muscles when looking through the Key Muscles and Key Poses of Yoga. The Yoga Mat Companion series deepens this visual experience by illustrating each pose in a step-wise fashion. This visual experience then translates to improvement in your asanas. Click here to page through all of our books.

Thanks for stopping by. Be sure to tune in this week for our next post. Also, many thanks for your support by sharing us on Facebook, Twitter and Google Plus.

Namaste’

Ray and Chris