What is a chiropractic adjustment and how does it help?

What is a chiropractic adjustment?

Many people are often confused about what a chiropractic adjustment actually is.

A chiropractic adjustment is a treatment where the provider applies a sudden quick thrust with minimal force to a joint at the end of passive range of motion. Passive range of motion is where the provider takes the joint to end range without any assistance from the patient and this is where the sudden quick thrust takes place.

This is also known as a manipulation and can be performed by many practitioners. Examples of different practitioners that perform manipulations include physiotherapists, osteopaths, and naturopaths

Why does my joint pop during the adjustment?

To get the story straight chiropractor don’t crack joints. They technically gap joints between two bones. During the manipulation, the joint and the surrounding musculature are brought to end range which stretches the joint capsule and gaps the joint.

This stretch of the joint capsule decreases the pressure within the joint cavity and causes nitrogen gas bubbles to be released from the synovial fluid. Usually, you will hear a pop or a cavitation during a manipulation and that is due to this release of nitrogen.

The anatomy of a joint and joint capsule

Dr. Pulmano performing a cervical adjustment

What are some of the possible benefits of a chiropractic adjustment

• Nourishes the articular cartilage
  • Since articular cartilage is highly avascular (no blood flow), the adjustment creates motion and fluid exchange of synovial fluid to bring nutrients to the articular cartilage.¹
• Decrease pain and possibly headaches
  • The pain gate theory suggest that non-painful stimuli (ex. chiropractic adjustments, exercise, massage, heat, cold, etc) closes neural pathways that perceive pain. In other words, sensations that don’t cause pain may decrease the amount of pain that you are currently experiencing.
  • The adjustment stimulates mechanoreceptors within the joint capsule and surrounding tissue. Mechanoreceptors are sensory receptors that perceive touch, stretch, vibration, and proprioception (awareness of your body in space). This non-painful stimulation of mechanoreceptors may decrease pain by closing neural pathways that perceive unpleasant/hurtful stimuli.^2,3
• Increase range of motion of a joint
  • may be due to breaking adhesions within joint capsule from the rapid stretch that accompanies the chiropractic adjustment. ⁴ Articular and periarticular adhesions form due to injury and prolonged immobilization.
• Can be beneficial for low back pain with lumbar hypo-mobility
  • However, if you have low back pain with lumbar hyper-mobility you would most likely benefit from a core stabilization program. ⁵
• Thoracic chiropractic adjustments may improve symptoms of shoulder impingement ⁶
  • Adequate thoracic extension is required for normal end range shoulder flexion/abduction. If thoracic extension is not adequate, the humerus may migrate upwards within the glenohumeral joint as a compensation pattern during overhead movement.
• Improve dorsiflexion (if talus impingement is present) of the ankle by manipulating the talocrural joint
  • Decreased ankle dorsiflexion has been shown to increase the chance of patellar tendon injury, ACL damage, and patellofemoral pain. ^7,8,9

References

1. Levangie, PK, and Norkin, CC: Joint Structure and Function: A Comprehensive Analysis, ed. 5 Philadelphia: FA Davis, 2011.
2. Paris, SV: mobilization of the spine. Phys Ther 59 (8): 988 -995, 1979.
3. Warkwick, R, and Williams, S (eds): Athrology. In Gray’s Anatomy, British ed. 35. Philadelphia: WB Saunders, 1973
4. Shekelle PG. Spine Update. Spinal Manipulation. Spine. 1994; 19: 858
5. Fritz JM, Whitman JM, Childs JD. Lumbar spine segmental mobility assessment: an examination of validity for determining intervention strategies in patients with low back pain. Arch Phys Med Rehabil. 2005;86 (9): 1745 – 1752.
6. Bergman GJ, Winters JC, Groenier KH, et al. Manipulative therapy in addition to usual medical care for patients with shoulder dysfunction and pain: a randomized, controlled trial. Ann Intern Med, 2004; 141: 432 – 439
7. Malliaras P, Cook JL, Kent P. Reduced ankle dorisflexion range may increse the risk of patellar tendon injury among vollyball players. J Sci Med Sport. 2006; 9:304-309
8. Lewit K. Manipulation Therapy Musculoskeletal Medicine. Edinburgh, Scotland: Churchill Livingstone/Elsevier; 2010.
9. Bell DR. Effect of limting ankle dorisflexion range of motion on lower extremity kinematics and muscle activation patterns during a squat. J Sports Rehabil. 2012;21:144.