“. . . 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



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.



29 comments:

  1. This is so very informational because I have an injury and this is explaining what it is.

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    1. Good to hear, Virgolady. Make sure you confirm your injury with your doctor and follow their guidelines in management of it. Don't self diagnose. Best~Ray

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    1. Thanks for your compliment, Sheree. Best~Ray

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  3. Well said Ray and Chris. You raise some good points in regards to the NYT article. In my opinion middle age is simply the time when we all near our maximum capacity for tolerating a lifetime of sub-optimal movement patterns on top of old injuries. Yoga is just one way in which these cumulative issues come to light, and the one that just happened to get the press this month. It's a shame that not more people and practitioners alike realize the equal importance of strength and muscular engagement in yoga.

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    1. Thank you Ya-Ling Liou! I think your comment is brilliant--sums the issue up much better than I could have. Namaste'~Ray

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  4. When are you teaching in California ...

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    1. Hi Marcia,
      I'm in California (LA) at the end of summer 2014. Check the workshop link above for dates and location. Best~Ray

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  5. love your site!
    I am an anatomy geek and appreciate that you are bringing up topics and blogs like this!

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  6. Thank you so much for sharing all this amazing informative information. It's really wonderful. I remember terrible hip pain after I had a baby and repeatedly going to see my doctor. In the end she wanted me to get tested for Lyme disease! Never a mention of join laxity or ligamentous laxity as a result of pregnancy. My feet went flat, my knees knocked in, my hips were sore and I went from doctor to doctor and it wasn't until I discovered yoga (and it took years) that I finally was able to pull my body structure back into alignment.

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    1. Glad to hear you sorted things out cgk--yoga helped me as well. All the best with your practice and health! Ray

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  7. Ditto to all the comments above; I find this to be the most informative site I've seen, and look forward to your posts! Thank you for your knowledge, insight, and sharing! I'm looking up your California visit for next year!!

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    1. Hi Yogaomgrl,

      Many thanks for your compliment on our work! Look forward to seeing you at one of our workshops. Best~Ray

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  8. Assuming good alignment, can you suggest some yoga poses that help and those that hurt with a torn hip labrum? Not much that I can find on web. Someone said to avoid pigeon?

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    1. Hi Cheryl,

      If someone has a symptomatic torn labrum, they should follow the directions of their physician as to activity and management of the problem (always). In terms of asymptomatic (painless, no symptoms) labra, recommend you check out the article I referenced on the prevalence of tears in folks that have never injured themselves, have no pain, and no other symptoms of a labral tear. In that study, 69% of the joints studied in the volunteers. Best~Ray

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  9. Hi Ray - Thanks for your thoughtful response to the recent William Broad article. I appreciate your contribution and concurred with most of it. However, one of your claims is that it is safer to practice Vasisthasana with the hand straight down from the shoulder, rather than slightly forward of it, and that one of the reasons the yoga teacher mentioned in the article may have injured her shoulder was because she was demonstrating the posture with the hand forward of the shoulder.

    I practice and teach this posture precisely as you suggest not to teach it, with the hand slightly forward of the shoulder, and it's likely that at least some of your other readers do as well. I would argue that the alignment is more skillful and the posture is safer this way because it sets the arm at a 90 degree angle to the shoulder girdle, orients the head of the humerus toward the center of the shoulder socket, and places the humerus in a more direct line with the clavicle, all of which creates a direct line of force into the sternum. For anyone with wrist issues, this alignment also creates less stress on the wrist flexors and median nerve because there is less wrist extension. With the arm straight down from the shoulder as you suggest, while it would make the posture a little easier because the arm bones will be more vertical relative to gravity, the line of force through the humerus won't be in line with the clavicle, which could likely create more of shearing force at both the acromioclavicular and sternoclavicular joints that over time could lead to a repetitive strain injury.

    As to why the teacher in question got injured, it seems like her condition, multidirectional shoulder instability, was the main predisposing factor. I also wonder if she was working her serratus anterior to stabilize, upwardly rotate and protract the scapula into the humerus. And as you mention, if she was working the muscles of her rotator cuff to stabilize the head of the humerus in the glenoid fossa. If either of these muscle groups are weak, or if they weren't being activated, then Vasisthasana is a super risky posture for someone with laxity in the shoulder joint ligaments and joint capsule. I'm personally a big fan of doing rotator cuff strengthening exercises with therabands as a kind of "cross-training" for yoga students that do a lot of weight-bearing postures on the arms.

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    1. Hi Jason,

Thanks for stopping by--glad you like the post. I also appreciate your input on the post--some interesting insight. On reflection, here are some thoughts on your post. The reason this person injured herself was because she performed the pose out of alignment with the weight bearing axis and subluxed her shoulder. She had a propensity for subluxation because she had MDI. I know because I confirmed that, both in the clinic and the operating room. She also had never injured herself practicing with the arm aligned under the shoulder. The main reason I presented that injury was to illustrate joint hypermobility and the need for awareness of muscular stabilization. I'm not particularly dogmatic about saying to do poses one way or the other. Rather, I think it is important to understand the differences between variations. Knowledge of biomechanics helps in that regard, understanding that there is much more to learn (for all of us) about that subject as well.

      
In terms of the rationale regarding the orientation of the glenoid, it is important to recognize that this bone has a small surface area relative to the humeral head (by design, for mobility of the joint). It is also very shallow (compared to the hip, for example). Thus, the humeral head can translate on the glenoid, especially if gravitational forces are directed as shown, the ligamentous stabilizers are less than normal—and the muscles are not being carefully engaged to compensate for the lax ligaments. In this particular case, the sheer forces resulted in subluxation of the humeral head and a posterior labral tear. As to someone who does not have ligamentous laxity and engages the muscular stabilizers, they have much more latitude when practicing a pose that supports the body weight. BTW, having the arm vertical makes it much easier in relation to the muscular effort required to maintain the position as well as stabilize the humeral head in the glenoid (in my opinion). So I would disagree on an angled arm being more "skillful". In terms of wrist extension and the median nerve, many poses have the wrist in the position shown; Full arm balance, chaturanga, bakasana--to name just a few. If you are concerned about carpal tunnel syndrome from extending the wrist, how would you recommend doing these poses?

      
In terms of a repetitive stress injury to the AC and SC joints from side plank, I find your theory highly speculative. First, folks don't typically practice this pose repetitively--they usually practice it once or twice in a session. Second; how would you differentiate the injury in a yoga practitioner who also practices many other poses with the hands supporting the body, including dog pose, chaturanga, (much more repetitively). In fact, I would say that theory is highly unlikely (and I specialize in shoulder injuries). I recommend being careful about speculating on "possible injuries" to support a theory (both with your example of AC/SC injury and median nerve injury).

      For sure, rotator cuff strengthening is important. I like using Garudasana and Gomukhasana, as well as co-activation of the rotators in the shoulders, especially in poses like side plank. Therabands are good too—use them for most cuff injuries. I practice and teach the pose as I describe, for the reasons I stated, but don’t have a problem with variations on it. I also recommend using good muscular engagement in either variation. Makes it safer and more beneficial. I should add that this injury was a rare occurrence, considering the numbers of folks doing yoga. It’s the first I’ve seen like that from yoga, and an unusual location for a labral tear in general. 

Best~Ray

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  10. I feel the stress at my scapula when I placed my supporting arm directly below my shoulder. Therefore my supporting arm is always slightly forward of my shoulder and it help to reduce the stress.
    I can't figure out the reason.

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    1. Hi Abbey,
      Thanks for your input on the post. Best~Ray

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  11. Hi
    ray
    i want some information regarding parvatasana.

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  12. Hi Ray,
    In relation to your article on labral tears and the condition of joint hypermobility.. I was hoping that you might be able to give me your opinion. I experience a terrible pain around and behind my left shoulder when stretching up into Urdhva Dhanurasana. I also experience this pain but more so when I have been sleeping on my left side for a while and I change position. I'm assuming this pain relates back to when I was doing an Ashtanga class back in 2010 when our teacher assisted me into the advance pose for Marichyasana as the discomfort is in the same area and feels quite similar to what I had experienced back then. Thereafter my shoulder were quite stiff and it took me a while to get back into poses like Gomukhasana. Any feedback would be great. Thank you so much. Natalie

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    1. Hi Natalie,
      Thanks for posting. Although I have some ideas on what may be happening in your shoulder (based on your symptoms), I can't give you an opinion without examining you myself. I would recommend you see a sports med or shoulder doc on it. Sorry I can't be of more help on that, but it's not good medicine to diagnose things without a careful work-up. Best~Ray

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  13. Hi Ray,
    What a treat to read your in depth response(s) and to have the visual aids to illustrate your analysis. As a "recovered hyper mobile" dancer and yogini, I truly appreciate the specific examples you shared, in particular about the very unusual shoulder labrum tear. Centrating joints and developing proprioception around the body's most suitable "fit" in a pose saves students from aches, pains and surgeries down the road. This is a must-read for all teachers of movement. THANKS! Jill

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    1. Hi Jill,
      Great to hear from you! Hope all is going well. Totally agree with your thoughts about the joints--I think it is also the key to the therapeutic benefits of the practice. Yoga, practiced mindfully is one of the best ways to improve proprioception and strength (along with all of the other benefits). Thanks for commenting--hope to see you in Toronto this year! Ray

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  14. Hi Ray,

    I typically practice vasistasana with my hand slightly forward of my shoulder lifting my hips high and working on getting the sole of the bottom foot to the floor. This greats the tensegrity effect of an arch which feels very safe to me.

    If the body was kept in a straight line without creating an arch by lifting the hips strongly I could see how it would be dangerous to have the bottom hand in vasistasana forward of the shoulder. But with the hips lifted it feels very comfortable.

    What are your thoughts on this?

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    1. Hi Gayle,

      I think the pose can be done both ways. I prefer having the supporting arm vertical for the reasons I describe, and also engage the lower side abs, hip abductors and the peroneus longus and brevis (of the lower leg). This creates an arch as well, with the forces directed down through the arm. As I mention to Jason above, I think the key, however you choose to do the pose, is to use a progressive approach, with good engagement of the muscles that stabilize the shoulder. This is even more important for folks with joint hypermobility, like person I referenced in this blog post. As I also mentioned to Jason, I'm not particularly dogmatic about a particular way to do a pose, rather one should be aware of the various factors contributing to stability and work with them.

      Thanks for your input!

      Ray

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  15. nice article
    Boost Your Energy With Yoga , Yoga is a deeply spiritual practice, improve stamina, strength and body flexibility, concentration and balance, improved metabolism.
    Yoga Teacher Training Rishikesh

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