Can chiropractic manipulation change joint position?

A review of the evidence

Many people believe that chiropractors can change the alignment of the spine through manipulation. The theory is that they can identify specific vertebral segments that are “out” of alignment, and then crack them back “in.” However, the evidence does not support this belief. Although manipulation might relieve pain for some people, it is not likely that this happens by changing the alignment of the spine. A better explanation would be some form of neuromodulation, such as placebo. Following is a brief review of the relevant evidence.

What causes the “crack” and what does it do?

Several studies have examined the cause of the audible pop that occurs during a chiropractic manipulation. The popping sound is created by a cavitation, which is a small movement of the vertebrae away from each other and then back together.¹ There is no evidence that cavitations create meaningful long-term changes in vertebral position, and some studies have shown that manipulation cannot change the position of the sacroiliac joint² or the neck.³

Can “cracks” be targeted at specific vertebrae?

Other studies have examined whether chiropractors can accurately target the cavitation at a specific vertebrae. Accuracy would be important if you believe that cavitation is causing a change in position, because missing the target would take vertebrae “out” of alignment instead of “in.”

In one study, chiropractors were tested in their ability to cause cavitations in specific segments of the lumbar spine. They hit the target less than half the time, with the average miss being at least one vertebra away.⁴ This is probably because the forces created by manipulation spread out over a broad area, and cannot be targeted to a specific location.⁵

Do cracks even matter for the result?

In any event, it seems that the efficacy of a chiropractic adjustment in reducing pain does not depend on the location of the cavitation or even the existence of an audible pop.⁶⁷ Further, simply mobilizing a joint provides a similar benefit to cracking it⁸, as does mobilizing vertebrae at random, compared to selecting a specific vertebrae that is supposedly out of place.⁹ Although spinal adjustments may be able to relieve pain and improve range of motion for some people, the likely mechanism is neurophysiological, not structural.¹⁰

The bottom line

My general advice for consumers of pain treatment is: if it feels good do it. But educate yourself as to why it feels good. If you don't, you might end up spending a lot of time and money with treatments whose effects could be obtained elsewhere in a way that is far cheaper, convenient, and empowering. Passive treatments like chiropractic are an option, but rarely a necessity. If a treatment doesn't make you feel any better than an activity like yoga, stretching, mobility drills, general exercise, or just going for a walk, ditch it.

References

1. Cramer et al. (2012). Quantification of Cavitation and Gapping of Lumbar Zygapophyseal Joints During Spinal Manipulative Therapy. Journal of Manipulative and Physiological Therapeutics. 35(8), 614–21.

2. Tullberg (1998). Manipulation Does Not Alter the Position of the Sacroiliac Joint. A Roentgen Stereophotogrammetric Analysis. Spine. 23(10), 1124–1129.

3. Shilton et al. (2015). Does Cervical Lordosis Change After Spinal Manipulation for Non-Specific Neck Pain? A Prospective Cohort Study. Chiropractic & Manual Therapies 23, 33.

4. Ross et al. (2004). Determining Cavitation Location During Lumbar and Thoracic Spinal Manipulation: Is Spinal Manipulation Accurate and Specific? Spine. 29(13),1452–7.

5. Bialosky et al. (2009). The Mechanisms of Manual Therapy in The Treatment of Musculoskeletal Pain: A Comprehensive Model. Manual Therapy. 14(5), 531–8.

6. Flynn et al. (2003). The Audible Pop Is Not Necessary for Successful Spinal High-Velocity Thrust Manipulation in Individuals with Low Back Pain. Archives of Physical Medical Rehabilitation. 84(7), 1057–60.

7. Moorman AC, Newell D. Impact of audible pops associated with spinal manipulation on perceived pain: a systematic review. Chiropr Man Therap. 2022 Oct 4;30(1):42. doi: 10.1186/s12998-022-00454-0. PMID: 36195914; PMCID: PMC9531394.

8. Gross et al. (2010). Manipulation or Mobilisation for Neck Pain: A Cochrane Review. Manual Therapy. 15(4), 315-33; Schomacher (2009). The Effect of An Analgesic Mobilization Technique When Applied at Symptomatic or Asymptomatic Levels of The Cervical Spine in Subjects with Neck Pain: A Randomized Controlled Trial. The Journal of Manual & Manipulative Therapy. 17(2), 101–108.

9. Nim CG, Downie A, O'Neill S, Kawchuk GN, Perle SM, Leboeuf-Yde C. The importance of selecting the correct site to apply spinal manipulation when treating spinal pain: Myth or reality? A systematic review. Sci Rep. 2021 Dec 3;11(1):23415. doi: 10.1038/s41598-021-02882-z. PMID: 34862434; PMCID: PMC8642385.

10. Bialosky et al. (2009). The Mechanisms of Manual Therapy in The Treatment of Musculoskeletal Pain: A Comprehensive Model. Manual Therapy. 14(5), 531–8.

---

Picture courtesy of Wikimedia Commons