The concept of subluxation has always been at the heart of chiropractic theory.1 It is therefore a very important word to define.1 When defining subluxation one must consider linguistic, biomechanical, pathophysiological and clinical concepts.1,2,3 Growth of knowledge in these fields has led to considerable evolution of the definition of subluxation since the word was first used in a chiropractic context.1,3
How a chiropractor defines and uses subluxation from a linguistics point of view will depend heavily on their training.1 This is because language is used during training to pass on knowledge, including the concept of a subluxation, from one generation of chiropractors to the next.1 This is evident within the healthcare professions because it has been said that different healthcare professionals such as
From a biomechanical point of view a subluxation can be seen as anything that impedes the normal functioning of a joint.2 Any anatomical structure that can influence a joint such as bone, cartilage, synovial fluid, joint capsule, muscles and ligaments can be part of the cause of a biomechanical subluxation.2 When muscles are hypertonic they effect the function of a joint and can contribute to a subluxation.2 If there is scar tissue in or surrounding the joint it can restrict the range of motion of the joint and cause a subluxation.2 Meniscoids which are a part of the synovial tissue of synovial joints can become trapped in the joint and impede joint motion.2 Cartilage inside the articular capsule relies on synovial fluid for lubrication and nutrition.2 If the joint is not being regularly loaded or is not moving properly the cartilage will not be exposed to a proper flow of nutrients which can lead to degeneration and worsen a subluxation.2
Some physiological responses can cause or exacerbate a spinal lesion which can be considered subluxations. If muscle spindle receptors are overactive they can cause muscles to become hypertonic which can impair the joint as mentioned above.2 Joint mechanoreceptors are affected as well by subluxations and can lead to some of the clinical symptoms of subluxations.2 Inflammation is commonly present with a subluxation and can be thought of a cause, aggravating factor or clinical symptom of a subluxation.3
Clinical Syndromes and Possible Effects of the Adjustment
People with subluxations commonly present with pain, restricted range of motion, reduced activity, disability and sometimes neurological symptoms.2,3 Specific symptoms will vary depending on the specific anatomical structures involved in the subluxation.2 Adjustments have the potential to help underlying causes of subluxation and therefore mitigate the symptoms associated with subluxations.2An adjustment can reset muscle spindles and reduce muscle hypertonicity.2 A manipulation can stimulate mechanoreceptors improving kinesthesis and reducing pain.2 Adjustments can also help a patient by releasing trapped meniscoids.2 By taking a joint through its full range of motion a manipulation can help the articular cartilage to receive nutrition, improve lubrication and break down scar tissue.2 An adjustment can also reduce inflammation.2 After an adjustment endorphin levels can also rise in a patient which would have an analgesic effect.2 With everything that is now known about types of spinal lesions and the benefits adjustments can have, chiropractors are optimally positioned to help patients who suffer from these conditions.
1. Budgell, Brian. A linguistics perspective on the word subluxation in the chiropractic literature. CP 1102: Foundations of Chiropractic Principles and Practices. 2016 July 26 [Cited 2017 April 8]. Available from: https://courses.cmcc.ca/portal/site/1fcb32f1-55e8-4c4e-8088-859c54001146/page/119aaa7b-3659-40c3-8e0c-78c9b26a6dad
2. Ross, Kim. The chiropractic theories script_SM [Powerpoint]. CP 1102: Foundations of Chiropractic Principles and Practice. 2016 July 19 [Cited 2017 April 8]. Available from: https://courses.cmcc.ca/portal/site/1fcb32f1-55e8-4c4e-8088-859c54001146/page/119aaa7b-3659-40c3-8e0c-78c9b26a6dad
3. Leach, Robert A. The Chiropractic Theories: A textbook of Scientific Research. 4th edition. Maryland: Lippincott Williams & Watkins; 2004.