Manipulation of the Cervical Spine

Original Editor - Riccardo Ugrin

Top Contributors - Riccardo Ugrin and Blessed Denzel Vhudzijena  

Introduction[edit | edit source]

The cervical spine is often a cause or a contributing cause for pain in the upper limb, in the head or in the dorsal region of the back. It is important to analyse the effectiveness and the efficiency of the manipulation techniques for manage pain. The safety and the contraindications of manipulation of the cervical spine were deeply analysed in the last decades, in order to proof the High Velocity Low Amplitude Thrust (HVLAT) as a technique to provide pain relief. Recently the IFOMPT (International Federation of Orthopaedic Manipulative Physical Therapists) Cervical Framework, was developed based upon the best contemporary evidence and expert opinion to assist clinicians during their clinical reasoning process when considering presentations involving the head and neck[1].

Anatomy of Cervical Spine[edit | edit source]

The cervical spine consists of seven distinct vertebrae, two of which are given unique names:

  • The first cervical vertebrae (C1) is known as the atlas.
  • The second cervical vertebrae (C2) is known as the axis.
    Cervical spine


There are two different joints present throughout the vertebral column: The disc joint (determines how much vertebral motion is possible at a particular segmental level), and the facet joints (determine the type of motion)

  • Disc Joint, between vertebral bodies – adjacent vertebral bodies are joined by intervertebral discs, made of fibrocartilage (cartilaginous joint, known as a symphysis). As a whole, the disc joint itself has three major functions:
  1. The disc joint bears the weight of the body above it. The increasing size of the vertebral bodies and the discs attached to them descending the spine helps the disc joints bear the increasing weight of the portion of the body above it.
  2. The disc joint’s thickness allows for a great deal of motion. Overall, the intervertebral discs comprise 25% of the height of the entire spine. In the cervical spine, they total 40% of its height. The greater the relative height of the discs compared to vertebral body height, the greater the possible motion at that region of the spine.
  3. The intervertebral discs help to absorb shock
  • Facet joint, formed by the articulation of superior and inferior articular processes from adjacent vertebrae (synovial joint). The scientific name for facet joints is zygapophyseal joints, hence they are also often known as Z joints. Facet joints function to guide motion at that segmental joint level of the spine. Facet joints determine the type of motion (i.e., the direction of motion) that can occur there. At the upper cervical spine, the plane of the facets is perfectly horizontal in the transverse plane. Descending the cervical spine, the orientation of the facets gradually transition to be more vertical in the frontal plane. As a general rule, the plane of the cervical facets is usually considered to be an oblique plane with an approximately 45-degree angle between the transverse and frontal planes. This angle is often compared to that of the slope of a roof. The type of motion best afforded at each vertebral segmental joint level is important to know and understand when performing joint mobilization


For more visit Cervical Anatomy

Description of Manipulation[edit | edit source]

The HVLAT of the cervical spine it is a technique, not a treatment. The clinical diagnosis, the functional and segmental restriction of range of movement and the anamnesis represent the usual care of the evaluation. By performing a thorough examination and using clinical reasoning, clinicians may be able to prevent the majority of adverse events and improving patient safety.With uncertainty regarding screening tools,[2] [3]clinicians must use additional strategies (e.g. red flags) for decision-making when choosing to use an HVLAT (High-Velocity Low-Amplitude Technique).[4] However it is demonstrated that mobilization and/or manipulation when used with exercise are beneficial for persistent mechanical neck disorders with or without headache. Done alone, manipulation and/or mobilization were not beneficial; when compared to one another, neither was superior. [5]

The kinematic of HVLAT of cervical spine is still controversial. The hypotesis is to create a torque to separate the articular surface of joints.[6] There are different type of HVLA techniques that combine oblique pulling manipulation or the cervical rotation–traction torque[7]. When the type of manipulation involved exclusive rotational thrust it is find the largest representation of adverse events[8]

  • Mean thrust duration: 158ms in a range from 117 to 250 ms.[9][10]
  • Mean of de-rotation displacement before thrust: 4,8 degrees[9][11]
  • Mean thrust displacement/ angle: 11,4 degrees in a range from 6.0 to 22.5[9]
  • Average peak thrust velocity: 127 degrees/sec[9]
  • Mean peak force applied: 118N[12]

The ability to perform a successful adjustment with HVLA therapy will, at times, elicit a "popping" sound. The restrictive barrier should be engaged entirely before applying the thrust. Finally, after executing the HVLA technique, the practitioner should reassess the range of motion and the somatic dysfunction treated. A successful result would lead to approximately 70% or greater return in the restricted range of motion and/or relief of pain. [13]

Cervical Manipulation[edit | edit source]

HVLAT of the Cervical Spine [14]

  1. Upper cervical HVLAT hand contact: Radial border of proximal phalanx on arch of Atlas, elbow at 90 degrees in direction of thrust; cradle hand at posterior/lateral occiput
  2. Create barrier: Utilize ipsilateral side-bend, side shift away by lunging forward, P-A extension, and rotation away
  3. Thrust: Into the arc of rotation toward the undersurface of the eyes with the thrust hand while simultaneously rapidly supinating opposite forearm
  • Mean of the ROM obtained during a HVLAT:[15]
  1. 30 degrees of rotation
  2. 46 degrees of lateral bending
  3. 2 degrees of flexion

It was found that axial rotation and lateral bending were correlated and in opposite direction. The peak of rotation and the peak of lateral bending occourred simultaneously to produce the thrust.

Cervico-Thoracic Junction Manipulation[edit | edit source]

Cervico-Thoracic Junction manipulation in prone [16]

  1. Cervico-Thoracic Junction HVLAT hand contact: Radial border of proximal phalanx on arch of C7-T1 or CTJ, elbow at 90 degrees in direction of thrust; cradle hand at posterior/lateral temporal bone.
  2. Create barrier: Utilize short leverage hand to create the barrier to CTJ on the articular pillar. The long leverage hand utilize ipsilateral side-bend, controlateral rotation and P-A extension.
  3. Thrust: the short leverage hand give the "lateral break" on CTJ toward the opposite axilla while simultaneously rapidly the opposite forearm give the rotation and side bend impulse.

Neurophysiological Effects[edit | edit source]

So far, the exact mechanism through which spinal manipulation works has not been established. Experimental studies conducted on both animal and human subjects have indicated that the mechanical stimulation of manipulation produces a barrage of input into the dorsal horn of the spinal cord, which initiates a cascade of neural responses involving complex interactions between the peripheral nervous system and manipulation. [17][18] Research propose different assumption to describe the effects.

One mechanism underlying the effects of spinal manipulation may, therefore, be the manipulation's ability to alter central sensory processing by removing subthreshold mechanical or chemical stimuli from paraspinal tissues. Spinal manipulation is also thought to affect reflex neural outputs to both muscle and visceral organs. Substantial evidence demonstrates that spinal manipulation evokes paraspinal muscle reflexes and alters motor neurone excitability.[19]Another effect could be the effective secondary stimulation of the dorsal periaqueductal gray (dPAG), only suggested by Wright [20]. In addition it was suggested[21] also a lessening of temporal summation in the dorsal horn cells secondary a HVLAT on the lumbar and thoracic spine. [22]

  • Neurophysiological effect > Biomechanical effect[23]:
  1. Peripheral Mechanisms: changes in blood level of B-endorphines, endogenous cannabinoids, seroronin and substance-P after manual therapy
  2. Spinal Mechanisms: counter irritant to modulate pain. Manual therapy could also be effective in the Gate-Control of pain theory because it bombard the central nervous system with sensory input. So HVLAT could be indirectly implicate in spinal cord mediated effect on hypoalgesia and reduction in motoneuron pool activity.
  3. Supraspinal Mechanisms: it had been supposed an influence on the supraspinal descending pain inhibitory system. Infact it was been demonstated MRI activation of amygdala, PAG, and anterior cingulate cortex during manual therapy. Those cortical areas are instrumental in pain experience.
  • Increase in ROM following thrust manipulation due to a reduction in pain levels and resting tension of surrounding soft tissue[23]
  • No change in facet joint space following cervical manipulation[24]
  • Analgesic effect:
  1. Decrease activity of central pain processing centers[23] [25]
  2. reduction in dorsal horn activation rates leading to decreased pain and decreased resting tension in surrounding soft tissue [26][27][28]
  3. Reduction in pain pressure thresholds locally and distally [29]

"POPPING" Sound[edit | edit source]

Example of cavitation in a MCP joint[30]

Cavitation sounds (‘cracks’, ‘clicks’ or ‘pops’) associated with spinal thrust manipulation are commonly observed in clinic. The audible release is caused by a cavitation process whereby a sudden decrease in intracapsular pressure causes dissolved gasses in the synovial fluid to be released into the joint cavity. Once a joint undergoes cavitation, the force-displacement curve changes and the range of motion of the joint increases. [31] It is seen in patients with healthy joints as well as those with somatic dysfunction. After an articular release, there is a difference in joint spacing-with the release increasing the distance between articular surfaces.[32]

Although bubble collapse, or the cavitation model[33] has been widely accepted for the past four decades as the mechanism of “joint cracking”, a more recent study by Kawchuk et al[34] reported a “dark intra-articular void” during MCP distraction. Notably, this “dark intra-articular void” was associated with concurrent sound production; that is, the “joint cracking” was associated in time with cavity formation (rather than cavity collapse) within the synovial fluid, and with an average of 1.89 mm of joint surface separation. Kawchuk et al referred to this process as tribonucleation; that is, when sufficient distractive force overcomes the viscous attraction or adhesive forces between opposing joint surfaces, rapid separation of the articulation occurs with a resulting drop in synovial pressure, allowing dissolved gas to come out of solution to form a bubble, cavity, clear space or void within the joint.


It remain still controversial another fenomena related to the "popping" sound that collide against previous theories. Infact after a joint manipulation had take place, there is a refractory period in which no other "popping"sound could been evocate.[35] This 15-30 minutes refractory period is believed to be due to the presence of micro-bubbles of gas in the synovial fluid.[36]However those studies analysed the cavitation in the phalangeal metacarpal joint searching for the increase in joint spase and the decrease in joint density. Despite of this there are no evidence of gas in the joint space or increase in zygapophyseal space after HVLAT of the cervical spine joints[35].

Real-Time Visualization of Joint Cavitation[37]

In light of this, there are not consistent with the understanding of cavitation in joints, in particular the refractory period and in the cervical spine.The traditional expectation of a single pop or cavitation sound emanating from the target or dysfunctional facet joint during HVLA thrust manipulation is not consistent with the existing literature for the upper cervical, lower cervical, thoracic or lumbar regions. Moreover, the evidence suggests that HVLA thrust manipulation directed at the spine creates multiple cavitation sounds.[38]

Reggars [39]

  • Average number of cavitations at C3/C4 was 2.5 per subject per thrust
  • High of 5 audible “pops”
  • Low of 1 audible “pop”

Dunning.[40]

  • Average number of cavitations
  • 3.57 per side
  • 6.95 per subject


Nevertheless, the question of whether these multiple cavitation sounds emanate from the same joint, adjacent ipsilateral or contralateral joints, or even extra-articular soft-tissues remains to be elucidated[41]

Despite of that practitioner observed that for HVLA thrusts with a primary leverage of rotation the resulting cavitation was most likely to occur on the contralateral side to the applicator. For side bending thrusts, the resulting cavitation was no more likely to occur on the contralateral or ipsilateral sides.[42]

Contraindications[edit | edit source]

Before doing a HVLAT of the cervical spine it is necessary proceed with a clinical anamnesis. The research of contraindication it is necessary to avoid advers neurologic and orthopedic events. The following are the major contraindications found for cervical spine manipulations.:

  • Patient refusal or worsening of symptoms with previous manipulations
  • Fractures of vertebrae: it is possible to have a fracture of vertebrae if a major trauma occours (car accident or an head injury) with cervical pain in standing position and with/without nervous system symptoms to the limbs. To make diagnosis of fracture to the cervical spine a X-ray evaluation is needed. With symptoms and without recent X-ray evaluations it is possible to discriminate the risk of fractures applying the Canadian C-Spine Rule (CCR)[43]: the CCR is a decision-making tool used to determine when radiography should be utilized in patients following trauma. It is not applicable in non-trauma cases, if the patient has unstable vital signs, acute paralysis, known vertebral disease or previous history of Cervical Spine surgery and age <16 years. 
  • Acute whiplash
  • Dislocation of the cervical vertebrae
  • Acute disc herniation. In presence of signs or symptoms of neurological impairment or radiculopathy it represent a contraindication to HVLAT. However Murphy (2006) concluded that is unlikely that a HVLAT to cervical spine would cause a healthy disc to become herniated, but it is possible that the manipulation caused preexisting asymptomatic disc herniation to become symptomatic.[44] It may be reasonable to recommend MRI or CT imaging to rule out in case of significant risk factors.[45]
  • Down syndrome[46]
  • Chiari malformation
  • Tumor/bony malignacy and Osteoporosis. It may be reasonable to recommend MRI or CT imaging to rule out in case of significant risk factors.[45]
  • Trasverse Ligament
    RRecent cervical surgery: an HVLAT can force the arthrodesis between vertebrae causing paralysis.
  • Rheumatoid arthritis: the sinovial joints are affected in Rheumatoid arthritis. The trasverse ligament of the atlas is in close relationship with the atlanto-axial joint. The degeneration of the sinovial tissue of the joint could affect the trasverse ligament[47]. Because of that the dens is no longer anchored and an HVLAT can move up the cervical spine, causing paralysis.
  • Vascular Pathologies of the Neck: the signs and symptoms of a vascular pathology of the neck are usually the 5D and the 3N:
    1. Dysphagia,
    2. Dysarthria,
    3. Diplopia,
    4. Dizziness,
    5. Drop Attack.
    6. Nistagmo,
    7. Numbness,
    8. Nausea

Cervical Arterial Dysfunction and Cervical Spine Manipulation[edit | edit source]

Vertebral Artery

In the last decades clinicians were asking if there are some relations between the Cervical Arterial Dysfunction (CAD) and Cervical Spine Manipulation. However it is not actually demonstrate that the manipulation can cause a CAD. Otherwise it is possible that a patient can actually be visited during an acute dissecation of the vertebrobasilar arterial system (VBA)[48]. It represent a relative contraindication if there is a previous diagnosis of VBA insufficiency[13]

  • Lee at al (1995) in a 2 years retrospective study of CAD and HVLAT found a deep connection where 21% of patients had neurological signs occoured after a chiropratic manipulation.[49]
  • However Klougart et al (1996) did a 10 years retrospective study on the incidence of CAD after a chiropratic HVLAT finding one case of CVA appeared for every estimated 1.3 million cervical treatment sessions.[50]
  • Conversely there is a study that estimated the force needed to disrupt the Vertebrobasilar Artery (VBA). They concluded that under normal circumstances, a single typical (high-velocity/low-amplitude) SMT thrust is very unlikely to mechanically disrupt the VBA. [51] Indeed a review of literature demonstrate that HVLAT of the cervical spine performed by trained clinicians does not appear to place undue strain on the vertebral artery, and thus does not seem to be a factor in vertebrobasilar injuries.[52] Similarly a recent systematic review found no epidemiologic studies to support the hypothesis that HVLAT of the cervical spine is associated with an increased risk of internal carotid artery dissection[53].
  • Cassidy et al. in 2008 found no excess risk of VBA stroke associated chiropractic care compared to primary care. The increased risks of VBA stroke associated with chiropractic visits is likely due to patients with headache and neck pain from VBA dissection seeking care before their stroke. [48]
  • In a more recent study Murphy[54] found that current evidence suggests that HVLAT of the cervical spine is associated with but not causally related to CADs, and it can be expected that patients with undetected vertebral artery dissection and stroke (VADS) will continue to see chiropractic physicians and it is essential that focused attention be made in an attempt at detection of this uncommon but potentially devastating disorder.
  • Controversy surrounds the dependability of vertebral artery testing before manipulation, with studies concluding that it is not possible to conclude the accuracy of pre-manipulative tests. Studies may indicate that the pre-manipulative tests do not seem reliable as a screening procedure[55].  Nevertheless, the possibility of vertebral artery disease must be entertained before performing cervical manipulation[13].

Indication[edit | edit source]

There are no practice guidelines where the HVLAT are raccomanded. [56] Nevertheless the difficult to find licterature or studies with a high level of raccomandation it does not mean that HVLAT of the cervical spine it is ineffective. However the evaluation of the signs and symptoms of the patient must guide the clinicians to choose when manipulate the cervical spine could be an option to have the best outcome. [24] In fact the primary use of cervical manipulation is not raccomanded as first option. It is demonstrated that cervical spine mobilisations and strenght and mobility exercise have the best outcome. Eventually both therapies can be associated with thoracic spine manipulations.

The clinicians could use the HVLAT of cervical spine in the following pathologies:

  • Cervicogenic Headaches [57][58][59]
  • A result of stiff and painful upper cervical segments
  • Unilateral headaches
  • Symptoms start in neck and run to fronto-occular area
  • Neck Related Arm Pain [57]
  • Motion Restriction[63]
  • Somatic Dysfunction[64]
  • Trigger Points within Surrounding Soft Tissue[65][10]
  • Active mouth opening limitation. Authors offer different possibilities[66]
  1. the "new" position of the craniocervical junction may have modified jaw position and hence ROM
  2. The manipulation procedure may have increased cervical ROM facilitating an increase in mouth opening
  3. reduction of reflex inhibition, allowing the masseter muscle to relax and thus an increase mouth opening ROM

Findings suggest that manipulation and mobilisation present similar results for every outcome at immediate/short/intermediate-term follow-up. Multiple cervical manipulation sessions may provide better pain relief and functional improvement than certain medications at immediate/intermediate/long-term follow-up. [67]

Example Plan of Care/Progression for Appropriate Patient:

First Visit
  1. It is advised to avoid performing cervical manipulation during the initial visit
  2. Recent research gives support to building therapeutic alliance (TA) with a patient, even suggesting patient-reported level of TA is a significant predictor of outcomes in back pain
  3. Suggested/possible initial manual interventions:

• Cervical mobilizations • Thoracic mobilizations • Cervico-thoracic junction mobility • Sub occipital release techniques • SNAGS • Upper cervical flexion-rotation MET

Second Visit Suggested/possible manual interventions:

• Cervical mobilizations • Thoracic manipulation • Cervico-thoracic junction manipulation

Third Visit
  1. Cervical manipulation if patient is indicated
  2. Waiting a few visits allows time to gauge patient response to prior manual interventions, build therapeutic alliance, and increase patient trust
Fourth Visit
  1. Always re-assess patient at the beginning of the visit following a cervical manipulation to measure patient response and change in status
  2. Continue with interventions as appropriate based on patient response

References[edit | edit source]

  1. Rushton A, Carlesso L, Flynn T, Hing W, Rubinstein S, Vogel S et.al. International Framework for Examination of the Cervical Region for Potential of Vascular Pathologies of the Neck Prior to Musculoskeletal Intervention: International IFOMPT Cervical Framework. Journal of Orthopaedic & Sports Physical Therapy. 2023; 53(1) : 1-51 https://doi.org/10.2519/jospt.2022.11147
  2. Bolton PS, Stick PE, Lord RS. Failure of clinical tests to predict cerebral ischemia before neck manipulation. J Manipulative Physiol Ther. 1989 Aug; 12(4):304-7.
  3. Westaway MD, Stratford P, Symons B. False-negative extension/rotation pre-manipulative screening test on a patient with an atretic and hypoplastic vertebral artery. Man Ther. 2003 May; 8(2):120-7.
  4. Puentedura EJ, March J, Anders J, et al. Safety of cervical spine manipulation: are adverse events preventable and are manipulations being performed appropriately? A review of 134 case reports. J Man Manip Ther. 2012;20(2):66-74.
  5. Gross AR, Hoving JL, Haines TA, Goldsmith CH, Kay T, Aker P, Bronfort G; Cervical Overview Group. A Cochrane review of manipulation and mobilization for mechanical neck disorders. Spine. 2004 Jul;29(14):1541-8.
  6. Harwich AS. Joint Manipulation: Toward a General Theory of High-Velocity, Low-Amplitude Thrust Techniques. J Chiropr Humanit. 2017;24(1):15-23.
  7. Huang X., Lin D., Liang Z. Deng Y., He Z., Wang M., Tan J. Li Yi., Yang Y., Huang W. Mechanical Parameters and Trajectory of Two Chinese Cervical Manipulations Compared by a Motion Capture System. Frontiers in Bioengineering and Biotechnology, 2021; 9:644   
  8. Di Fabio RP. Manipulation of the Cervical Spine: Risks and Benefits, Physical Therapy, Jan 1999; 79, (1):50–65
  9. 9.0 9.1 9.2 9.3 Ngan JM, Chow DH, Holmes AD. The kinematics and intra- and inter-therapist consistencies of lower cervical rotational manipulation. Med Eng Phys. 2005 Jun;27(5):395-401
  10. 10.0 10.1 Reed WR, Cao DY, Long CR, Kawchuk GN, Pickar JG. Relationship between Biomechanical Characteristics of Spinal Manipulation and Neural Responses in an Animal Model: Effect of Linear Control of Thrust Displacement versus Force, Thrust Amplitude, Thrust Duration, and Thrust Rate. Evid Based Complement Alternat Med. 2013;2013:49203
  11. Evans, David & Breen, Alan. . A Biomechanical Model for Mechanically Efficient Cavitation Production During Spinal Manipulation: Prethrust Position and the Neutral Zone. Journal of manipulative and physiological therapeutics.(2006);29. 72-82.
  12. Kawchuk GN, Herzog W, Hasler EM. Forces generated during spinal manipulative therapy of the cervical spine: a pilot study. J Manipulative Physiol Ther. 1992 Jun;15(5):275-8.
  13. 13.0 13.1 13.2 Elder B, Tishkowski K. Osteopathic Manipulative Treatment: HVLA Procedure - Cervical Vertebrae. [Updated 2021 Oct 10]. In: StatPearls [Internet].
  14. How to perform a Cervical Manipulation - Grade 5 - Osteopathic HVT. Available from: https://www.youtube.com/watch?v=-POU-8VK0-s
  15. Klein P, Broers C, Feipel V, Salvia P, Van Geyt B, Dugailly PM, Rooze M. Global 3D head-trunk kinematics during cervical spine manipulation at different levels. Clin Biomech (Bristol, Avon). 2003 Nov;18(9):827-31.
  16. CT junction manipulation. Available from: https://www.youtube.com/watch?v=U92PqoIRQz8
  17. del Rey RR, Saavedra Hernández M, Blanco CR, del Cerro LP, Rodríguez RA. Short-term effects of spinal thrust joint manipulation on postural sway in patients with chronic mechanical neck pain: a randomized controlled trial. Disability and Rehabilitation (2020) 0:0, pages 1-7.
  18. G. Gyer, J. Michael, J. Inklebarger, J. Shanker Tedla, Spinal manipulation therapy: is it all about the brain? A current review of the neurophysiological effects of manipulation, Journal of Integrative Medicine (2019)
  19. Pickar JG. Neurophysiological effects of spinal manipulation. Spine J. 2002 Sep-Oct;2(5):357-71.
  20. Wright A. Hypoalgesia post-manipulative therapy: a review of a potential neurophysiological mechanism. Man Ther. 1995 Nov;1(1):11-6.
  21. George SZ, Bishop MD, Bialosky JE, Zeppieri G Jr, Robinson ME. Immediate effects of spinal manipulation on thermal pain sensitivity: an experimental study. BMC Musculoskelet Disord. 2006 Aug 15;7:68.
  22. Bishop MD, Beneciuk JM, George SZ. Immediate reduction in temporal sensory summation after thoracic spinal manipulation. Spine J. 2011 May;11(5):440-6
  23. 23.0 23.1 23.2 Bialosky JE, Bishop MD, Price DD, Robinson ME, George SZ. The Mechanisms of Manual Therapy in the Treatment of Musculoskeletal Pain: A Comprehensive Model. Man Ther. 2009;14(5):531-538
  24. 24.0 24.1 Blanpied PR, Gross AR, Elliott JM, Devaney LL, Clewley D, Walton DM, Sparks C, Robertson EK. Neck Pain: Revision 2017. J Orthop Sports Phys Ther. 2017 Jul;47(7):A1-A83.
  25. Bolton A, Moran RW, Standen C. An investigation into the side of joint cavitation associated with cervical spine manipulation. Int J Osteopath Med. 2007;10(4):88-96.
  26. Fernández-de-las-Peñas C, Pérez-de-Heredia M, Brea-Rivero M, Miangolarra-Page JC. Immediate effects on pressure pain threshold following a single cervical spine manipulation in healthy subjects. J Orthop Sports Phys Ther. 2007;37(6):325-329
  27. Bialosky JE, Bishop MD, Robinson ME, George SZ. The relationship of the audible pop to hypoalgesia associated with high-velocity, low- amplitude thrust manipulation: a secondary analysis of an experimental study in pain-free participants. J Manipulative Physiol Ther. 2010;33(2):117-124
  28. Pickar JG. Neurophysiological effects of spinal manipulation. Spine J. 2002;2(5):357-371.
  29. Coronado RA, Gay CW, Bialosky JE, Carnaby GD, Bishop MD, George SZ. Changes in pain sensitivity following spinal manipulation: A systematic review and meta-analysis. J Electromyogr Kinesiol. 2012;22(5):752-767
  30. https://body-motion.co.uk/uncategorized/spinal-manipulation-whats-the-crack/
  31. Brodeur R. The audible release associated with joint manipulation. J Manipulative Physiol Ther. 1995 Mar-Apr;18(3):155-64
  32. Protopapas MG, Cymet TC. Joint cracking and popping: understanding noises that accompany articular release. J Am Osteopath Assoc. 2002 May;102(5):283-7.
  33. Unsworth A, Dowson D, Wright V. 'Cracking joints'. A bioengineering study of cavitation in the metacarpophalangeal joint. Ann Rheum Dis. 1971 Jul; 30(4):348-58.
  34. Kawchuk GN, Fryer J, Jaremko JL, Zeng H, Rowe L, Thompson R. Real-time visualization of joint cavitation. PLoS One. 2015; 10(4)
  35. 35.0 35.1 Cascioli V, Corr P, Till Ag AG. An investigation into the production of intra-articular gas bubbles and increase in joint space in the zygapophyseal joints of the cervical spine in asymptomatic subjects after spinal manipulation. J Manipulative Physiol Ther. 2003 Jul-Aug;26(6):356-64.
  36. Sandoz R. The significance of the manipulative crack and other articular noises. Ann Swiss Chiropr Assoc 1969:4:47- 68.
  37. Real-Time Visualization of Joint Cavitation. Available from: https://www.youtube.com/watch?v=aJLU-4M-hdE
  38. Dunning J, Mourad F, Zingoni A, et al. CAVITATION SOUNDS DURING CERVICOTHORACIC SPINAL MANIPULATION. Int J Sports Phys Ther. 2017;12(4):642-654.
  39. Reggars JW. The manipulative crack: Frequency analysis. Chriopr Osteopat. 1996;5(2):39-44
  40. Dunning J, Mourad F, Barbero M, Leoni D, Cescon C, Butts R. Bilateral and multiple cavitation sounds during upper cervical thrust manipulation. BMC Musculoskelet Disord. 2013;14:24-24.
  41. Cascioli V Corr P Till Ag AG. An investigation into the production of intra-articular gas bubbles and increase in joint space in the zygapophyseal joints of the cervical spine in asymptomatic subjects after spinal manipulation. J Manipulative Physiol Ther. 2003;26(6):356-364
  42. Bolton A., Moran RW., Standen C. An investigation into the side of joint cavitation associated with cervical spine manipulation. International Journal of Osteopathic Medicine, 2007; 10 (4): 88-96
  43. Stiell IG, Wells GA, Vandemheen KL, Clement CM, Lesiuk H, De Maio VJ, Laupacis A, Schull M, McKnight RD, Verbeek R, Brison R. The Canadian C-spine rule for radiography in alert and stable trauma patients. Jama. 2001 Oct 17;286(15):1841-8.
  44. Murphy DR. Herniated disc with radiculopathy following cervical manipulation: nonsurgical management. Spine J. 2006 Jul-Aug;6(4):459-63.
  45. 45.0 45.1 Oppenheim JS, Spitzer DE, Segal DH. Nonvascular complications following spinal manipulation. Spine J. 2005 Nov-Dec;5(6):660-6; discussion 666-7. .
  46. Ali FE, Al-Bustan MA, Al-Busairi WA, Al-Mulla FA, Esbaita EY. Cervical spine abnormalities associated with Down syndrome. Int Orthop. 2006;30(4):284-289.
  47. Vetter M, Oskouian RJ, Tubbs RS. “False” ligaments: a review of anatomy, potential function, and pathology. Cureus. 2017 Nov;9(11).
  48. 48.0 48.1 Cassidy JD, Boyle E, Côté P, et al. Risk of Vertebrobasilar Stroke and Chiropractic Care: Results of a Population-Based Case-Control and Case-Crossover Study. Eur Spine J. 2008;17(Suppl 1):176-183.
  49. Lee KP, Carlini WG, McCormick GF, Albers GW. Neurologic complications following chiropractic manipulation: a survey of California neurologists. Neurology. 1995 Jun;45(6):1213-5.
  50. Klougart N, Leboeuf-Yde C, Rasmussen LR. Safety in chiropractic practice, Part I; The occurrence of cerebrovascular accidents after manipulation to the neck in Denmark from 1978-1988. J Manipulative Physiol Ther. 1996 Jul-Aug;19(6):371-7.
  51. Symons BP, Leonard T, Herzog W. Internal forces sustained by the vertebral artery during spinal manipulative therapy. J Manipulative Physiol Ther. 2002 Oct;25(8):504-10.
  52. Herzog W, Leonard TR, Symons B, Tang C, Wuest S. Vertebral artery strains during high-speed, low amplitude cervical spinal manipulation. J Electromyogr Kinesiol. Oct 2012;22(5):740-746.
  53. Chung CL, Cote P, Stern P, L’Esperance G. The Association Between Cervical Spine Manipulation and Carotid Artery Dissection: A Systematic Review of the Literature. J Manipulative Physiol Ther. Jan 3 2014.
  54. Murphy DR. Current understanding of the relationship between cervical manipulation and stroke: what does it mean for the chiropractic profession?. Chiropr Osteopat. 2010;18:22. Published 2010 Aug 3.
  55. Hutting N, Verhagen AP, Vijverman V, Keesenberg MD, Dixon G, Scholten-Peeters GG. Diagnostic accuracy of premanipulative vertebrobasilar insufficiency tests: a systematic review. Man Ther. 2013 Jun;18(3):177-82.
  56. Smith J , Bolton PS. What Are the Clinical Criteria Justifying Spinal Manipulative Therapy for Neck Pain? A Systematic Review of Randomized Controlled Trials, Pain Medicine, April 2013; 14 (4): 460–468
  57. 57.0 57.1 57.2 Puentedura EJ, Cleland JA, Landers MR, Mintken PE, Louw A, Fernandez-de-Las-Penas C. Development of a clinical prediction rule to identify patients with neck pain likely to benefit from thrust joint manipulation to the cervical spine. J Orthop Sports Phys Ther. 2012;42(7):577-592.
  58. 58.0 58.1 Childs JD, Cleland JA, Elliott JM, et al. Neck pain: clinical practice guidelines linked to the International Classification of Functioning, Disability, and Health from the Orthopaedic Section of the American Physical Therapy Association. J Orthop Sports Phys Ther. 2008;38(9):A1-A34.
  59. 59.0 59.1 Cleland JA, Childs JD, Fritz JM, Whitman JM, Eberhart SL. Development of a clinical prediction rule for guiding treatment of a subgroup of patients with neck pain: use of thoracic spine manipulation, exercise, and patient education. Phys Ther. 2007;87(1):9-23.
  60. Gross A, Langevin P, Burnie SJ, et al. Manipulation and mobilisation for neck pain contrasted against an inactive control or another active treatment. The Cochrane database of systematic reviews. 2015(9):Cd004249
  61. Dunning JR, Cleland JA, Waldrop MA, et al. Upper cervical and upper thoracic thrust manipulation versus nonthrust mobilization in patients with mechanical neck pain: A multicenter randomized clinical trial. J Orthop Sports Phys Ther. 2012;42(1):5-18.
  62. Chaibi A, Stavem K, Russell MB. Spinal Manipulative Therapy for Acute Neck Pain: A Systematic Review and Meta-Analysis of Randomised Controlled Trials. J Clin Med. 2021;10(21):5011.
  63. Martínez-Segura R, Fernández-de-las-Peñas C, Ruiz-Sáez M, López-Jiménez C, Rodríguez-Blanco C. Immediate effects on neck pain and active range of motion after a single cervical high-velocity low-amplitude manipulation in subjects presenting with mechanical neck pain: a randomized controlled trial. J Manipulative Physiol Ther. 2006 Sep;29(7):511-7
  64. Chu J, Allen DD, Pawlowsky S, Smoot B. Peripheral response to cervical or thoracic spinal manual therapy: an evidence-based review with meta analysis. J Man Manip Ther. 2014;22(4):220-229.
  65. Fernandez-de-Las-Penas C. Interaction between trigger points and joint hypomobility: A clinical perspective. J Man Manip Ther. 2009;17(2):74-77.
  66. Mansilla-Ferragut P, Fernández-de-Las Peñas C, Alburquerque-Sendín F, Cleland JA, Boscá-Gandía JJ. Immediate effects of atlanto-occipital joint manipulation on active mouth opening and pressure pain sensitivity in women with mechanical neck pain. J Manipulative Physiol Ther. 2009 Feb;32(2):101-6
  67. Gross A, Langevin P, Burnie SJ, Bédard-Brochu M, Empey B, Dugas E, Faber-Dobrescu M, Andres C, Graham N, Goldsmith CH, Brønfort G, Hoving JL, LeBlanc F. Manipulation and mobilisation for neck pain contrasted against an inactive control or another active treatment. Cochrane Database of Systematic Reviews 2015, Issue 9.