Perspectives on Yoga Inputs in the Management of Chronic Pain

Physical

Chronic pain is not just a symptom. It takes the form of disease through active processes, in the form of multiple plastic changes that together determine the duration and intensity of the pain.[2] There is central and peripheral sensitization in the nervous system with neuro-chemical and neuro-anatomical components that eventually results in hyperexcitability, recruitment and disinhibition of the pathways, that amplifies and perpetuates chronic pain.

Besides the actual nociceptive initiators, there are other strong neuro-endocrine-immunologic components to chronic pain perceptions. The breathing becomes mainly thoracic with lesser excursion of the diaphragm.[3] There is sustained deep muscle tension characterized by repetitive static loads to the muscles and psychological stress, especially of the postural groups of muscles.[4]

Emotional

Chronic pain decreases function and causes anxiety and depression.[5] The physiology is in a state of persistent stress with the hypothalamic – pituitary- adrenal axis and the sympathetic system, in a state of hyper arousal. It affects sleep, energy reserve and appetite adversely.[6] High scores on a psychosocial screening and emotional distress (Hopkin’s symptom check list) during the acute episode were also significantly associated with non-recovery and persistence of pain.[7]

Social

Interpersonal relations, which are a crucial part of social interactions for all human beings, are often adversely influenced by chronic pain. With constant unremitting pain, the sufferer feels loss of control over the situation looses self confidence and withdraws. Some may become irritable, hostile and aggressive. People who are close to the ill person could react with over protectivity, avoidance, guilt or resentment.

The loss of role, the fear of dependency and future sufferings continuously perturb the chronic pain patient. There is a sense of isolation and loneliness. There is evidence to suggest inadequate social problem solving as an important factor in the pathogenesis of chronic pain.[89]

How do asanas help in chronic pain conditions?

Asanas, the yogic postures, are popularly identified as ‘The Yoga’ by the lay person. It is but, one of the eight limbs of yoga philosophy. There are different types of asanas: physical culturing, balancing, relaxing and meditative.

Effect of asanas on the musculo-skeletal system

In most chronic pain conditions, whether they are directly related to musculoskeletal system [low and upper backache, tension headaches, myofascial pain states, fibromyalgia] or not, there is high contribution of the static load, due to habitual deep muscle tension that adversely affect microcirculation within muscles and the underlying viscera. This is further aggravated by the sedentary life style, lack of exercise, poor posture and distancing from nature [There is high incidence of demineralization of bones due to inadequate exposure to sun].

In contrast to exercises, asanas are isometric and can only be studied by subtle electromyographic (EMG) techniques. [There is lower EMG activity in comparison to exercises, which can be further lowered by bringing in awareness and emphasis on relaxation (9)] Asanas bring steadiness, health and lightness of the body and optimize tissue functioning. Asanas are useful adjuncts in the maintenance phase for reconditioning the body, realignment of skeleton and for correction of postures. It opens up the vital flow of energy through the body, which is subjectively perceived as positive sense of wellbeing. Well chosen culturing and balancing asanas can strengthen muscles and correct the posture. This, coupled with relaxation, breaks the cycle and reverses the pain reinforcing forces.

Various asanas have compressive / de-compressive effects on the blood flow and lymph flow of underlying tissues through abdominal muscular stretches and contraction in combination with appropriate spinal movements. During acute exacerbations, awareness and progressive relaxation takes away a fair proportion of pain and the person feels more in control, which itself hastens remission.

Effect of asanas on the neuro-endocrine flow

Asanas stabilize the autonomic nervous system. They influence the endocrine system and nerve plexuses by increasing local blood flow by gravity [sarvangasana on thyroid] contraction of surrounding muscle [Bhujangasana on lumbar plexus] or by pressure release [Mayurasana on celiac plexus].[10] Studies done in regular practitioners show a decrease in cortisol and cholinesterase levels, which reflect quietening of the stress response. There is evidence of endogenous opioid release during sustained stretching of muscles.[11]

How does Pranayama contribute to management of chronic pain?

Pranayama is the controlled expansion of vital energy. In practice, it comprises of yogic breathing techniques; as breath is the one expression of vitality that has both voluntary and involuntary components and multiple associations.

Pain modifies frequency, depth and patterns of respiration. This is due to pain’s emotional component as well as due to the phylogenetically acquired tendency to immobilize the affected area to avoid further injury. If the affected area is localized at the trunk, this may mean considerable restriction of respiratory movements of the chest and/or abdomen.

In chronic pain states, breathing is invariable strained, shallow and mainly thoracic. This is perceived by the physiology as a sustained stressful state and this in turn affects other rhythmic phenomena like neuronal flow and vital cyclic rhythms with high flat cortisol levels similar to arousal response[1213] Deep yogic breathing with prolonged exhalation relaxes most skeleton muscles. There is some indirect evidence that there is increased tonicity of the parasympathetic nervous system and overall lesser activation of the central nervous system.[14–16]

Pranayama on cognition states

Just as thoughts and emotions affect the breathing pattern, the converse is also true. Our breathing pattern is reflected internally as stressful or relaxed and can create consequential changes in the physiology. We are familiar with the technique of using slow breathing to come out of stress. Researchers have demonstrated amazing correlations between Electroenchephalography (EEG) patterns and breath patterns. Slow breathing increases the α waves in the EEG and adding feedback of breath sounds further significantly increased it from baseline.[17] Another study elicited a correlation between increase in α waves in the EEG and abdominal breathing,[18] which indicates that states of consciousness could be affected by patterns of breathing. It is impossible to stay angry or anxious while breathing in a slow, deep and reflective manner. Diaphragmatic breathing is probably the single most valuable thing that a patient in chronic pain can learn on the road to recuperation.

Effects of meditation on physiology and cognition

Neurobiological studies have recognized unique patterns of physiology at different levels of consciousness. Researchers[20] have compared physiological changes seen in supine posture and sleep with that in meditative states. The common findings during meditative states have been much more than just a deeper level of relaxation at physical level (reduced EMG activity in quadriceps, increased finger temperature, pulse volume and circulation, reduction in blood pressure and lactate, constant pCO² and pO² along with significantly reduced O² consumption. The cortisol levels came down while Prolactin and Ach levels increased). Deep meditation has proved to be a hypo-metabolic arousal state.[21] The O² uptake and CO² output are minimal as in deep sleep but the EEG pattern is that of complete alertness. One of the earliest studies in this respect was from AIIMS Delhi.[22] They showed persistent α waves with significant increased amplitude modulation, in the EEG. There is also a tendency towards synchrony of EEG patterns from the various scalp leads.

During self-awareness-based meditation techniques, the person attempts to cultivate the role of an impartial observer and a detached witness of all subjective phenomena including pain. In this way the frame of reference in which pain is experienced, changes. Using mediation to perceive pain may be also considered as a paradoxical technique decreasing the fear of pain.

Yoga is thus culturing of the mind and the body.

Backache

Misalignment of the musculoskeletal components of posture maintenance is found to be the commonest cause for backache. Relaxation asanas [makarasana, shavasana] followed by stretch [ardhakati chakrasana, ardhamatsyendrasana] and strengthening asanas [Bhujangasana and shalabhasana] help.[27] Introduction of strengthening asanas too early can aggravate the pain.

Pranayama with abdominal breathing initiates relaxation and addition of meditation and awareness maintains it. Gradually, the person becomes aware of his own control over the symptom progression.

Myofacial pain, Fibromyalgia

Here the primary cause is persistently stressful mindset, which gets reflected on the musculoskeletal system. Fibromyalgia is characterized by chronic muscle tension, systemic fascial adhesion and skeletal malalignment; accompanying is the overactive sympathetic nervous system,[28] inefficient motor activities restricted breathing patterns, fatigueability and low mood.

Yogic practices to regain control include methods of calming, physical self awareness and using minimum muscular effort for optimal results while maintaining full deep breathing that sends signals of relaxation internally. This approach has also been found useful in all other forms of stress -muscle tension – poor blood flow – pain syndromes e.g. tension head ache, RSI

Migraine[29]

Migraine involves a dysfunctional vascular system and has been associated with personality and stress. Preliminary studies for its control using yoga (stretching asanas for shoulder, back and neck, whole body relaxation, jala neti, pranayamas) show positive results.

Yogic breathing is a unique method, which helps balance the autonomic nervous system and influence psychological and stress-related disorders[30] Mechanisms contributing to a state of calm alertness include increased parasympathetic drive, calming of stress response systems, neuroendocrine release of hormones, and thalamic generators.

Knee pain

Osteoarthritis (OA) is the most common form of arthritis and a leading cause of disability. As there are no disease-modifying agents available for OA, the standard care of patients with osteoarthritis of the knees is aimed at reducing pain and improving the functioning of the knees by focusing on the surrounding tissues through exercise or external support. Regular pawanamukthasana [anti-rheumatic series] or BKS Iyengar (Padmavibhushan BKS Iyengar – is a proponent of a method of yoga named after him. His school is based in Pune, Maharashtra.) Yogic techniques[31] have been successfully used to contain the symptoms and disability. These are easily learnt techniques for regular mobilization of each joint of the body synchronized with breathing and awareness.

Neuropathic pain

Neuropathic pain is caused by nerve damage proximal to the sensory nerve endings in the skin. It has no protective or predictive value and inflicts significant sensory and emotional burdens on. Most neuropathic pain patients experience some improvement when physicians adopt a holistic approach to treatment. Components used from yoga are, yoga nidra with visualization, breath and body awareness, gentle equivalent stretch asanas for muscle groups and meditation.

There have been studies on successful use of upper body postures: improving flexibility; correcting alignment of hands, wrists, arms, and shoulders; stretching; and increasing awareness of optimal joint position during use to alleviate symptoms of specific areas like carpal tunnel syndrome.[32]

Cancer pain

Pain in cancer is a body-mind phenomenon and obviously requires therapy directed to both. The commonest techniques used are gentle regular mobilization through pawanamuktasana, which can be performed even by a bedridden patient, specific calming pranayamas and yoga nidra with visualization to sublimate the suppressed emotional components. If the patient is committed, meditation can be included. In malignant pain states, relaxation postures and yoga nidra (guided progressive deep relaxation technique which works in alignment with the sensorimotor cortex representation of the body) have been found to reduce analgesic requirements and improve sleep and reduce fatigue.

Besides improvement in the pain experience, there is significant improvement of other distresses including fatigue[33] insomnia and breathlessness. The “dissolution of body” experience and the oneness, that the pranayama and meditative methods provide allows an experience of healing and wholeness.[34] Increased self-understanding and self-acceptance, changed context of pain, increased control, life style improvements, group and social support involved in undertaking yogic activities all together contribute to improved quality of life.[35]