At its simplest, positional release techniques as used in manual therapy settings, involve the unloading of tissues, placing them into less-stressed, "ease" positions. In such a comfort state, a number of beneficial changes may emerge including reduced pain perception and reduced inflammation,¹⁵ greater local muscular strength, reduced fascial stiffness,^1,2 reduced pain-medication use and number of days of hospitalization, as well as enhanced peripheral circulation, post-surgically.¹¹

There are four main forms of PRT methods:³

1. SCS: Tissues are guided into an ease position, based on the patient's responses to changes in sensitivity to applied pressure. The position of ease is held for 90 seconds, or more, to allow change to occur. (See Figure 1.)
2. Functional Technique: Tissues are taken into their preferred directions of movement (ease), as determined by the practitioner's sense of tissue response, and held for 90 seconds or more, to allow change to occur.
3. Facilitated PRT: Which load (e.g. compression, distraction. shear), is added to Functional or SCS position of ease – reducing holding time to 20 seconds or less.
4. Other PRT approaches include "unloading" taping, sacrooccipital and craniosacral techniques, orthobionomy and McKenzie Exercise methods.

The benefits of reduced stimulation, applied to the whole body may help us to understand the effects of PRT. For example, time spent in a flotation tank, immersed in neutral temperature water, of high salt concentration to increase buoyancy - described as Restricted Environmental Stimulation Technique (REST) – reduces anxiety, depression and pain in individuals suffering chronic pain.

In 2001, Kjellgren et al, described 37 patients suffering from chronic pain who were randomly assigned to either a control group (17) or an experimental group (20) who received nine REST treatments over a 3-week period. The most severe pain intensity was significantly reduced, but low perceived pain intensity was not influenced. REST treatment elevated optimism, reduced the degree of anxiety or depression, and improved sleep.

In another study, Edebol et al (2008) reported the benefits of the REST method in the management of the chronic effects of whiplash injuries. And of course, relaxation, mindfulness, meditation approaches – are all known to be useful as means of reducing general over-sensitive states, whether mental, or physical. Here are some suggested mechanisms for manually induced stimulus reduction.

Neurolophysiological changes might involve muscle, fascial and joint mechanoreceptors (e.g. Ruffini corpuscles, Golgi tendon organs, muscle spindles),¹⁰ as well as pain receptors. To explore the role of muscle spindles, and the hypothesis that sensitivity of the deep tendon stretch reflex contributes to range-of-motion restrictions, Howell et al. (2006) measured stretch and H-reflex latency and amplitude before and after strain counterstrain treatment. The results suggest that SCS affected the sensitivity of the muscle spindle, thought to be heightened by the existence of tendonitis.

Proprioceptive theory is probably the most commonly discussed explanation for the efficacy of SCS. It is suggested that when a disturbed relationship exists between muscles and their antagonists, following strain, the positioning of these tissues into an unloaded, ease, position, may allow spindle resetting and partial or total resolution of inappropriate motor impairment.⁹

Mechanotransduction: Altered fibroblast responses resulting from changes in the shape and architecture of cells through mechanotransduction can be anti-inflammatory. Meltzer et al.¹⁴, observed that traumatized fascia disrupts the normal functions of the body, causing myofascial pain and reducing ranges of motion. Resulting inflammatory responses - involving fibroblasts - can be reversed in as little as 60 seconds by changes in load on the tissues, delivered either by counterstrain or myofascial release. In 2007, Standley & Meltzer observed that "fibroblast proliferation and expression/secretion of pro-inflammatory and anti-inflammatory interleukins may contribute to the clinical efficacy of indirect osteopathic manipulative techniques..." such as SCS. Standley and Meltzer (2008) also reported that "it is clear that strain direction, frequency and duration, impact important fibroblast physiological functions known to mediate pain, inflammation and range of motion."

Ligamentous reflexes: Solomonow¹³ identified the sensory potential and major ligamento-muscular reflexes that have inhibitory effects on associated muscles. He states, "If you apply only 60 to 90 seconds of relaxing compression on a joint... an hour+ of relaxation of muscles may result. This may come not only from ligaments, but also from capsules and tendon" (personal communication 2009). A possible clinical application of this ligamentous feature may be seen when joint "crowding" is induced as part of Facilitated Positional Release and/or SCS protocols. Such effects would be temporary – 20 to 30 minutes – but this would be sufficient time to allow an enhanced ability to mobilize or exercise previously restricted structures.

Wong¹⁶ summarizes current thinking regarding ligamento-muscular reflexes and SCS: Ligamentous strain inhibits muscle contractions that increase strain, or stimulates muscles that reduce strain, to protect the ligament.⁷ For instance, anterior cruciate ligament strain inhibits quadriceps and stimulates hamstring contractions to reduce anterior tibial distraction.⁷

Hydration: Crowding (compression) of soft tissues – as used in SCS and Facilitated Positional Release (FPR), has an effect on the water content of fascia, leading to temporary (20 to 30 minutes) of reduced stiffness of fascial structures – with the potential for enhanced mobility during that period. This window of opportunity can be usefully employed to enhance function and for the individual to experience less painful movement.

Hysteresis: In a study at the Philadelphia College of Osteopathic Medicine (Barnes 2012), 240 subjects were palpated for cervical articular somatic dysfunction. This was followed by use of a durometer to objectively measure soft-tissues overlying each cervical segment pre- and post-intervention, using a single consistent piezoelectric impulse, quantifying hysteresis (tissue stiffness/densification). Various soft-tissue techniques, including SCS, myofascial release, muscle energy technique and high velocity manipulation were tested. The results showed that all methods - but not the sham intervention - improved symptoms and stiffness of tissues but that SCS resulted in the most significant beneficil changes.

To what degree all, or any, of these mechanisms are operating during application of PRT in general, and StrainCounterstrain (SCS) in particular, remains to be more definitively established. Meanwhile positional release methods are among the safest and most effective ways of easing painful symptoms and inducing a healing response.³

References

1. Barnes P et al 2013 A Comparative Study of Cervical Hysteresis Characteristics after Various Osteopathic Manipulative Treatment (OMT) Modalities JBMT 17(1):89–94.
2. Benjamin S et al 1999 Normalized forces and active range of motion in unilateral radial epicondylalgia. J Orthopedic and Sports Physical Therapy 29: 668-676.
3. Chaitow L 2015, Positional Release Techniques (4th edition) ChurchillLivingstone, Elsevier.
4. Chaitow L DeLany J 2011 Clinical Applications of Neuromuscular Techniques (vol.1 2nd edition) ChurchillLivingstone.p259.
5. Collins CK 2007 Physical Therapy Management of Complex Regional Pain Syndrome I in a 14-Year-Old Patient Using Strain Counterstrain: A Case Report." Journal of Manual & Manipulative Therapy. 15(1):25-41.
6. Dyhre-Poulsen P, Krogsgaard MR. 2000 Muscular reflexes elicited by electrical stimulation of the anterior cruciate ligament in humans. Journal of Applied Physiology;89:2191-2195.
7. Howell, J. N., K. S. Cabell, et al. (2006). Stretch Reflex and Hodges P, Richardson C 1999 Altered trunk muscle recruitment in people with LBP with upper limb movement at different speeds. Archives of Physical Medicine Rehabilitation 80:1005–1012.
8. Huijing PA, Baar G. Myofascial force transmission via extramuscular pathways occurs between antagonistic muscles. Cells Tissues Organs 2008;188(4):400-414.
9. Jones J Bodywork & Movement Therapies 14:162.
10. O-Yurvati A et al 2005 Hemodynamic effects of osteopathic manipulative treatment immediately after coronary artery bypass graft surgery. JAOA 105(10):475-481.
11. Peters T MacDonald R Leach C . 2013 Counterstrain manipulation in the treatment of restless legs syndrome: A pilot single-blind randomized controlled trial; the CARL Trial." International Musculoskeletal Medicine. 34(4):136-140.
12. Solomonow M 2009 Ligaments: a source of musculoskeletal disorders. J. Bodywork & Movement Therapies 13(2) 136-154.
13. Standley P Meltzer K 2007 Modeled Repetitive Motion Strain and Indirect Osteopathic Manipulative Techniques in Regulation of Human Fibroblast Proliferation and Interleukin Secretion. J Am Osteopath Assoc. 107:527-536.
14. Urse GN 2012 Plantar fasciitis: A review Osteopathic Family Physician 4:68-71.
15. Wong CK 2012 Strain Counterstrain: Current concepts and clinical evidence. Manual Therapy 17:2-8.