Chronic Neck Pain

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Chronic neck pain is defined when neck pain has persisted for more than three months. Around 20-40% of patients with acute neck pain continue on to have chronic neck pain.

Definitions

Main article: Cervical Spine Pain Definitions

Cervical Spine Pain is pain perceived as arising from anywhere within the region bounded superiorly by the superior nuchal line, inferiorly by an imaginary transverse line through the tip of the first thoracic spinous process, and laterally by sagittal planes tangential to the borders of the neck. This definition doesn't necessarily mean the source lies in this region, only that the patient perceives the pain there. The definition also recognises that musculoskeletal causes of neck pain are typically felt posteriorly rather than anteriorly.

Referred pain is "pain perceived as arising or occurring in a region of the body innervated by nerves or branches of nerves other than those that innervate the actual source of pain"

Somatic referred pain is referred pain where the source originates in a tissue or structure of the body wall or limbs. A number of structures in the lumbar spine are capable of nociception including the lumbar zygapophysial joints, intervertebral discs, sacroiliac joints, and more.

Radicular pain is a subset of neuropathic pain, and refers to pain that is evoked with stimulation of the nerve roots or dorsal root ganglion of a spinal nerve. In radicular pain, the pain is felt in the peripheral innervation of the affected nerve.

Radiculopathy is objective loss of sensory and/or motor function as a result of conduction block in axons of a spinal nerve or its roots.

Epidemiology

The prevalence of chronic neck pain varies across populations. The prevalence increases with age, and is slightly higher in women. In a New Zealand survey, the prevalence of chronic pain in general was 16.9% Amongst individuals with chronic pain, chronic neck pain was present in 12% compared to 6.9% for the head (some of these are likely to be cervicogenic), and 24.1% for the back.[1]

Risk Factors

The most important risk factors for neck pain are psychosocial factors related to the work environment, rather than personal psychosocial factors. They include high job demands, low decision authority, low influence over the work situation or low job control, low co-worker social support, high psychological demand, and low decision latitude.[2]

Importantly, personal psychosocial factors do not appear to be determinants of neck pain. The psychological state only accounts for 2% of variance in symptoms with multivariate analysis.[2]

Refuted and weak to moderate risk factors for the development of neck pain[2]
Refuted Risk Factors Weak to Moderate Risk Factors
Degenerative disc disease Female
Zygapophysial joint osteoarthritis Previous injury
Smoking Working with machines
Socioeconomic status Occupation
Prolonged sitting at work station Educational level

Natural History and Prognostic Factors

The annual incidence of new episodes of neck pain is 14%, and 0.6% have disabling pain. Complete resolution occurs in ~37% over time, a further ~33% have some improvement, and in the remainder the neck pain persists.[3] At one year around half are still affected.[4] At 10 years around 25% still have moderate symptoms, and 7% are severely disabled.[5][6]

Refuted and weak to moderate prognostic factors for persistent neck pain after whiplash[7]
Refuted Prognostic Factors Weak to Moderate Poor Prognostic Factors Strong Poor Prognostic Factors
Age Sleep disturbance High initial pain intensity
Gender Cognitive impairments Hyperalgesia of the neck and remote from the neck
Psychological response Poor concentration Psychological distress
Compensation Neuroticism Engaging a lawyer
Past history of headache
Being unprepared for the collision

Aetiology

See also: Causes and Sources of Neck Pain

The zygapophysial joints are the single most common source of pain in both whiplash and heterogenous patient samples.

Prevalence Studies of Pain Sources in Chronic Neck Pain
Study Patients Blocks Relief Proportion
Barnsley 1995[8] Whiplash Concordant comparative MBB 100% 54%
Lord 1996[9] Whiplash Placebo-controlled MBB 100% 60%
Speldewinde 2001[10] Variety Concordant comparative MBB ≀ 1/10 36%
Manchikanti 2002[11] Variety Concordant comparative MBB 75% 60%
Yin 2008[12] Variety Concordant comparative MBB 100% 55%
Yin 2008[12] Variety Provocative discography 7/10

(pain not relief)

16%

Idiopathic Neck Pain

Idiopathic neck pain refers to neck pain that arose insidiously, i.e. in the absence of a specific inciting event or other explanation. Anatomically the muscles, discs, and joints of the cervical spine are all possible nociceptive generators, however there there is a lack of research into the pathophysiology of how pain might arise from these structures

Muscles: Muscle sprain as a cause of neck pain fits better in the acute setting rather than the chronic setting, as muscle injuries heal quickly. Muscle pain has been hypothesised to be a cause of chronic pain using terms such as muscle spasm, chronic muscle ischaemia, and trigger points. However there is no agreed method of diagnosis.

In chronic neck pain there is often muscle dysfunction. There is reduced activity of the deep cervical flexor muscles (longus cervicis and capitis), increased activity of the superficial flexors (sternocleidomastoid), and increased activity of the accessory neck muscles (anterior scalenes and trapezius). The reasons for this pattern is unclear but it is likely a secondary phenomenon, rather than the primary cause of pain.

Intervertebral Discs: With age there is disc dehydration and osteophytosis, however this has not been shown to be linked to pain. Without trauma, it is not clear why a disc should become painful, or if indeed it does at all.

Synovial Joints: The most likely source of nociception in chronic idiopathic neck are the synovial joints of the neck. These are the facet joints, atlanto-axial joints, and atlanto-occipital joints. However, imaging findings of osteoarthritis of the synovial joints don't correlate with pain, and so diagnosis is made with diagnostic local anaesthetic injections.

Post-traumatic Neck Pain

Main article: Chronic Post-Traumatic Neck Pain


The aetiology of chronic pain is clearer in the setting of whiplash and trauma in general. The most likely lesions are injuries to the zygapophysial joints and intervertebral discs.

Muscles: Muscles are unlikely to be implicated as a primary cause of persistent cervical pain following trauma.

Intervertebral Discs: The anterior annulus fibrosis can be torn or avulsed from the vertebral body in extension injuries. These injuries are likely to be painful, but may only be apparent in vivo rather than on imaging.

Synovial Joints: The zygapophyseal joints and lateral atlanto-axial joints are susceptible to extension injuries. Injuries include meniscoid contusions, intra-articular haemorrhage, capsular tear, annulus tear, subchondral articular fractures, and articular pillar fractures. These injuries are likely to be painful, but again are often not apparent on imaging.

Alar and Transverse Ligaments: Severe trauma can result in rupture of the suboccipital ligaments. The main clinical features are instability of the axis or spinal cord injury. In less severe trauma, there is radiological evidence that the alar and transverse ligaments can be injured in whiplash. Injury to the alar ligaments was more common than the transverse ligaments. Also alar ligament injury wasn't found in controls, while transverse ligament injury was found in controls. It isn't clear whether injury to these ligaments can result in chronic neck pain or, because they are at C1, cervicogenic headache. Patients may "feel" unstable and report that neck movement provokes nausea.

Psychological Factors

There is no evidence to support the view that chronic neck pain, whether post-traumatic or not, is secondary to somatization, conversion disorder, malingering, hypochondriasis, or due to secondary gain. A psychosocial label is not falsifiable, i.e. it cannot be refuted, and so it a belief rather than a valid diagnosis. For many patients a biomedical diagnosis cannot be made, but the Musculoskeletal Medicine view is generally that this is due to the infancy of research in this area, rather than the primary cause being nebulous psychosocial factors.

Assessment

Pain History

The duration of illness establishes whether the pain is acute or chronic. The circumstances of onset identify if it was post-traumatic, spontaneous, associated with another illness, or insidious in onset. The mode of onset refers to whether there was a sudden spontaneous onset of severe neck pain indicating a red flag condition.

The site of pain can be helpful for source localisation. Cervical referred pain tends to occur in distinctive patterns which have been validated in asymptomatic and symptomatic individuals undergoing procedures (See Cervical Pain Maps Grid). This localises the pain to a segment, but not to a particular structure such as disc or zygapophysial joint. However in those with widespread neck pain there is no localising clue.

The quality of pain is important as somatic pain is dull and aching. Neurogenic causes of pain are lancinating and sharp in quality.

The frequency and duration refer to whether the pain is episodic or constant, however this is not generally helpful diagnostically.

Aggravating factors can be useful as mechanical causes of pain are typically aggravated by neck movement and relieved by rest. Serious causes may be unrelated to movement and not relieved by rest. This is however a weak sign.

The associated features are important as they related to red flag conditions. A systematic enquiry about red flag symptoms is preferred, which should raise an alert in the doctor's mind.

Red Flags

Red Flags
  • Significant trauma (eg. fall in osteoporotic patient, motor vehicle accident)
  • Infective: (eg. fever, meningism, immunosuppression, intravenous drug use, exotic exposure, recent overseas travel)
  • Constitutional: (eg. fevers, weight loss, anorexia, past or current history of malignancy)
  • Iatrogenic: Recent surgery, catheterisation, venipuncture, manipulation
  • Neurological: Symptoms/signs especially of upper motor neuron pathology, vomiting
  • Genitourinary/Reproductive: UTI, haematuria, retention, uterine, breast
  • Endocrine: Corticosteroids, diabetes, hyperparathyroid
  • Gastrointestinal: Dysphagia
  • Integumentary: Infections, rashes
  • Cardiorespiratory: Cough, haemoptysis, chest pain, shortness of breath, diaphoresis, ripping/tearing sensation (dissection), CVD risk factors, anticoagulants
  • Rheumatological: History of rheumatoid arthritis (atlanto-axial disruption)
  • Awkward posture (atlantoaxial rotatory subluxation in children)


Physical Examination

Main article: Cervical Spine Examination

Physical examination is generally unhelpful diagnostically, however it is important as part of the doctor-patient relationship. Patients are often tender in certain areas and have restricted range of motion. Passive segmental motion can be assessed. However all these findings generally don't help with source localisation, and have poor reliability, validity, or both.

A full neurological examination is only necessary if the patient has neurological symptoms, not if pain is the only symptom. In the presence of isolated pain a screening neurological exam can be performed looking for weakness and numbness.

Investigations

Imaging

MRI is the best screening test for serious causes, however it is unlikely to be helpful diagnostically, unlike in chronic low back pain.

In general there is no link between cervical degenerative joint disease and pain. However, there is a slight clinical significance with degenerative disc (but not facet osteoarthritis) findings at the C5/6 level. There is also an association with marked (level 3) degenerative changes and neck pain.

Recently radiologists and surgeons are frequently using CT scintigraphy. This modality has 'concept validity.' It can detect small occult fractures and tumours. However it shows increased blood flow, not pain. It tends to miss cases where the pain is arising from soft tissue damage, for example capsule tears.

For tears to the transverse ligament of the atlas or of the alar ligaments, there are no tests that can pinpoint those structures as being a source of pain. However any cervical instability that arises due to injury can be identified through imaging. For the transverse ligament of the atlas, injury is suggested with widening of the atlanto-odontoid interval by more than 3mm on flexion films. Injury to then alar ligament is suggested with rotation of the atlas to more than 56 degrees on functional CT (contralateral ligament is injured).

Physiological Tests

As pain is a sensory experience, imaging studies are only helpful diagnostically if the abnormality has been previously shown to be correlated with pain in prevalence studies. In the absence of such a correlation, or when a definitive diagnosis is required, imaging can't be used to diagnose pain. Physiological tests are the criterion standard for identifying the source of an individuals chronic neck pain. Such physiological tests don't identify the cause of pain, only the source of pain. Imaging is sometimes helpful for identifying the cause of disc pain, but is typically unhelpful for zygapophysial joint pain.

Medial Branch Blocks

Medial branch blocks are the gold standard for evaluation of zygapophyseal joint pain, looking for concordant positive blocks. The most commonly affected joints by far are C2-3 and C5-6. Undertaking this procedure provides a diagnosis to around 60% of patients.

Algorithm

If a patient has lower cervical pain +/- shoulder pain then the most likely level is selected based on the pain maps, with C5-6 being more typical with upper trapezius region pain, and C6-7 being more typical with pain at the medial border of the scapula. Controlled blocks are done, and if positive then the diagnosis is zygapophysial joints pain. If they are negative then then next most likely level is selected, or investigations cease if other levels are excluded.

If a patient has upper cervical pain +/- headache then initially controlled blocks of the third occipital nerve is done to diagnosis C2-3 zygapophysial joint pain which is the most common cause of cervicogenic headache. If this is negative then the next step is lateral atlanto-axial joint blocks to diagnose C1-2 joint pain which is the second most common cause of cervicalgenic headache. If this is negative then the next step is C23-4 zygapophysial joint blocks to diagnose C3-4 zygapophysial joint pain.

In patients with both upper and lower cervical pain the most common pattern is upper cervical pain from C2-3 and lower cervical pain from C5-6 or C6-7. In such patients, both sites have to be treated for complete relief of their headache/upper neck pain and lower neck pain respectively.

Rationale

Controlled blocks are required to reduce the rate of false positives, as single blocks have a false positive rate of 27%[13], this is why the results from single block studies are effectively meaningless. There are two types of controls. Pharmaceutical controls use different agents (such as bupivacaine and lidocaine) on the same target at two different instances in time (such as separated by one week). Anatomic control involves injecting the agent to a different substance.

The ultimate pharmaceutical control is the placebo block (bupivacaine, lidocaine, and placebo). A local anaesthetic is used first, because if the pain isn't relieved then there is proceeding further. The second block is a random choice between placebo (normal saline), and a different local anaesthetic to the first one. In this setting, a positive response is relief of pain when an anaesthetic was used, and no relief when a placebo was used.

This scenario is only an ideal, as various forces make it difficult to undergo three separate diagnostic procedures. What is done as a practical alternative in many high quality studies and in reality in New Zealand is doing comparative local anaesthetic blocks.[14] With the protocol, the same block is done twice on two separate occasions, but with different local anaesthetics that are blinded to the patient. A concordant response is having a duration of relief that is concordant with the expected duration of the local anaesthetic, i.e. short lasting relief with lidocaine and long-lasting relief with bupivacaine. A discordant response is when the opposite situation occurs with longer relief with lidocaine. A concordant response to comparative local anaesthetic blocks has a false positive rate of 14% when compared to using placebo controls, while discordant responses have a 35% false positive rate.[15]

The third occipital nerve block is for evaluation of pain arising from the C2-3 zygapophyseal joint. This nerve also innervates semispinalis capitis and a small region of skin over the suboccipital region. The TON crosses the joint in a variable way, and the needle placement reflects this variability. Successful block is indicated by a patch of numbness.[16] Ultrasound rather than fluoroscopic guidance is an emerging technique and appears to be quite accurate with similar success rates between 95-100%. It was quicker and required fewer injections than fluoroscopy.[17][18]

C3-4 is quite uncommon to be affected on its own. The method of investigation is C3-4 medial branch blocks. C3-4 rarely causes headache, and when it does lower neck pain is the dominant symptom, with headache being secondary.

For the lateral atlanto-axial joints, the joint gets innervation from both the ventral and dorsal side. Therefore for this joint, the technique is infiltration of local anaesthetic into the joint itself. This is potentially hazardous. This is because if the needle is too medial then it can enter the dural sac and if the needle goes through the middle of the joint it may hit the C2 dorsal ganglion. The injection is done laterally. The vertebral artery lies over the lateral quarter of C1-2 in 1% of cases and this can be checked on imaging. Overpenetration is another risk, therefore the initial target is bone to indicate safe depth before moving it into the joint.

Cervical Discography

For the remaining 40% of patients that don't have zygapophysial joint pain, the diagnosis of discogenic pain can be considered.

Cervical discography is a technically demanding procedure and is very rarely done in New Zealand. Discography should only be considered if zygapophysial joint pain has been excluded through controlled medial branch blocks. This is because cervical discs are frequently false-positive when the individual has zygapophysial joint pain (41%).[19]

With imaging, disc degeneration is most common at C5-6 and C6-7 but positive disc stimulation occurs just as commonly at C3-4 and C4-5, and so it is important not to just target the sites with abnormal radiological findings. In fact, it is uncommon for a single disc to be painful, half of patients have three or more abnormal discs.[20]

In summary, the diagnosis of cervical discogenic pain can be made when

  1. Disc stimulation has been correctly performed
  2. Cervical zygapophyseal joint pain has been excluded at the segments being investigated
  3. Stimulation of the target disc reproduces concordant pain
  4. The pain that is reproduced is at least 7/10
  5. Stimulation of adjacent discs does not reproduce the patient's pain

Unlike with the lumbar spine, no manometric criteria have been developed.

The risk of discitis is 0.13% when prophylactic antibiotics are used, and 0.66% if not used.

There is no strong positive therapeutic utility for disc stimulation due to the limited treatment options for cervical discogenic pain. Surgery is only indicated is ~10% of cases with positive disc stimulation. The remaining individuals have too many affected discs at different levels. However there may be negative therapeutic utility in that negative disc stimulation could prevent surgery.[20]

Treatment

Exercises are the primary treatment option for the conservative management of chronic neck pain, but this is palliative in nature. For those with proven zygapophysial joint pain, radiofrequency neurotomy remains the only treatment that has a proven significant chance of cure.

TENS: low quality positive evidence for a modest reduction in pain. It must be high amplitude and high intensity with 4Hz frequency and 250Ts duration in order to be effective. [21]

Education: There is no benefit of education. Self-care strategies, ergonomics, exercise, self-care, relaxation vs no treatment or rest or physiotherapy or CBT was of no benefit.[22]

Traction: There is no statistically significant difference.[23]

Massage: Low level evidence that stand-alone massage has immediate or short-term effectiveness for pain and tenderness. Low level evidence that ischaemic compression and passive stretch may have been more effective in combination rather than individually for pain reduction.[24]

Exercise: This is a messy area. Exercise can be separated into support element (cardiac/pulmonary/metabolic), base element (extensibility/mobility/strength/endurance), modular element (patterns/synchronisation/proprioception/co-ordination), biomechanical element (static/dynamic stabilisation), cognitive/affective element (learning ability/compliance/motivation/emotional). In acute neck pain there is no evidence for exercise therapy. In chronic neck pain there is low evidence that the following are not effective: breathing exercises, general fitness training, stretching, feedback exercises combined with pattern synchronisation, and postural exercises. Mindfulness exercises minimally improved function but not global perceived effect at short term.[25]

Moderate quality evidence supports the following in chronic neck pain:

  • Cervico-scapulothoracic and upper extremity strength training to improve pain of a moderate to large amount immediately post treatment and at short-term follow up
  • Scapulothoracic and upper extremity endurance training for slight beneficial effect on pain at immediate post treatment and short-term follow up. The NNT was 4. The patient puts an elastic band under their feet, and abducts their arms to 90 degrees of shoulder abduction and 30 degrees of shoulder horizontal flexion. The elbows are slightly flexed. This is done for 2 minutes, as a single set, five times per week.[26]
  • Combined cervical, shoulder, and scapulothoracic strengthening and stretching exercises varied from a small to large magnitude of beneficial effect on pain at immediate post treatment and up to long term follow up and a medium magnitude of effect improving function at both immediate and short term follow up
  • Cervico-scapulothoracic strengthening/stabilisation exercises to improve pain and function at intermediate term

Manipulation: No evidence of benefit.

Pharmacological: Muscle relaxants, analgesics, and NSAIDs have limited evidence and unclear benefits. Lidocaine injection into myofascial trigger points was superior to placebo with an NNT of 3 for short term benefit of two weeks. Botox was ineffective. [27]

Surgery: No compelling data are available. Only low quality data have been published, which shows that it is at most a palliative procedure, with only a minority being rendered pain-free. For C1-2 joint pain, arthrodesis remains the only non-pharmaceutical biomedical treatment option, as neurotomy is not possible, and steroid injections have limited effect.

Multi-disciplinary Treatment: There is no evidence of benefit, and this includes high intensity treatment.[28]

Cognitive Behavioural Therapy: No clinically meaningful benefit.[29]

Radiofrequency Neurotomy: Highly effective in the context of concordant positive blocks, proven in a placebo controlled trial, and in long term follow up.[30][31][32][33] The lower cervical spine has a success rate of 70% for complete relief of pain.[30][31][32] For third occipital neurotomy the success rate is 86%.[33] If the pain recurs then the procedure can be repeated.[31][32][34]

References

  • Bogduk, Nikolai, and Brian McGuirk. Management of acute and chronic neck pain : an evidence-based approach. Edinburgh New York: Elsevier, 2006.
  1. ↑ Dominick C, Blyth F, Nicholas M. Patterns of chronic pain in the New Zealand population. N Z Med J. 2011 Jun 24;124(1337):63-76. PMID: 21946879.
  2. ↑ 2.0 2.1 2.2 Bogduk N, McGuirk B. Medical management of acute and chronic neck pain. An evidence-based approach. Amsterdam: Elsevier, 2006
  3. ↑ CΓ΄tΓ© P, Cassidy DJ, Carroll LJ, Kristman V. The annual incidence and course of neck pain in the general population: a population-based cohort study. Pain. 2004 Dec;112(3):267-273. doi: 10.1016/j.pain.2004.09.004. PMID: 15561381.
  4. ↑ Hill J, Lewis M, Papageorgiou AC, Dziedzic K, Croft P. Predicting persistent neck pain: a 1-year follow-up of a population cohort. Spine (Phila Pa 1976). 2004 Aug 1;29(15):1648-54. doi: 10.1097/01.brs.0000132307.06321.3c. PMID: 15284511.
  5. ↑ Gore DR, Sepic SB, Gardner GM, Murray MP. Neck pain: a long-term follow-up of 205 patients. Spine (Phila Pa 1976). 1987 Jan-Feb;12(1):1-5. doi: 10.1097/00007632-198701000-00001. PMID: 3576350.
  6. ↑ LEES F, TURNER JW. NATURAL HISTORY AND PROGNOSIS OF CERVICAL SPONDYLOSIS. Br Med J. 1963 Dec 28;2(5373):1607-10. doi: 10.1136/bmj.2.5373.1607. PMID: 14066179; PMCID: PMC1873933.
  7. ↑ Bogduk. Neck pain and whiplash. Wilson's Chronic Pain. 2008
  8. ↑ Barnsley et al.. The prevalence of chronic cervical zygapophysial joint pain after whiplash. Spine 1995. 20:20-5; discussion 26. PMID: 7709275. DOI.
  9. ↑ Lord et al.. Chronic cervical zygapophysial joint pain after whiplash. A placebo-controlled prevalence study. Spine 1996. 21:1737-44; discussion 1744-5. PMID: 8855458. DOI.
  10. ↑ Speldewinde et al.. Diagnostic cervical zygapophyseal joint blocks for chronic cervical pain. The Medical journal of Australia 2001. 174:174-6. PMID: 11270757. DOI.
  11. ↑ Manchikanti et al.. Prevalence of cervical facet joint pain in chronic neck pain. Pain physician 2002. 5:243-9. PMID: 16902649.
  12. ↑ 12.0 12.1 Yin & Bogduk. The nature of neck pain in a private pain clinic in the United States. Pain medicine (Malden, Mass.) 2008. 9:196-203. PMID: 18298702. DOI.
  13. ↑ Barnsley L, Lord S, Wallis B, Bogduk N. False-positive rates of cervical zygapophysial joint blocks. Clin J Pain. 1993 Jun;9(2):124-30. doi: 10.1097/00002508-199306000-00007. PMID: 8358135.
  14. ↑ Bogduk N. Diagnostic nerve blocks in chronic pain. Best Pract Res Clin Anaesthesiol. 2002 Dec;16(4):565-78. doi: 10.1053/bean.2002.0252. PMID: 12516892.
  15. ↑ Lord SM, Barnsley L, Bogduk N. The utility of comparative local anesthetic blocks versus placebo-controlled blocks for the diagnosis of cervical zygapophysial joint pain. Clin J Pain. 1995 Sep;11(3):208-13. doi: 10.1097/00002508-199509000-00008. PMID: 8535040.
  16. ↑ Kwon, Hyun-Jin et al. β€œAnatomical analysis of the distribution patterns of occipital cutaneous nerves and the clinical implications for pain management.” Journal of pain research vol. 11 2023-2031. 25 Sep. 2018, doi:10.2147/JPR.S175506
  17. ↑ Eichenberger U, Greher M, Kapral S, Marhofer P, Wiest R, Remonda L, Bogduk N, Curatolo M. Sonographic visualization and ultrasound-guided block of the third occipital nerve: prospective for a new method to diagnose C2-C3 zygapophysial joint pain. Anesthesiology. 2006 Feb;104(2):303-8. doi: 10.1097/00000542-200602000-00016. PMID: 16436850.
  18. ↑ Finlayson RJ, Etheridge JP, Vieira L, Gupta G, Tran DQ. A randomized comparison between ultrasound- and fluoroscopy-guided third occipital nerve block. Reg Anesth Pain Med. 2013 May-Jun;38(3):212-7. doi: 10.1097/AAP.0b013e31828b25bc. PMID: 23558370.
  19. ↑ Bogduk N, Aprill C. On the nature of neck pain, discography and cervical zygapophysial joint blocks. Pain. 1993 Aug;54(2):213-217. doi: 10.1016/0304-3959(93)90211-7. PMID: 8233536.
  20. ↑ 20.0 20.1 Grubb SA, Kelly CK. Cervical discography: clinical implications from 12 years of experience. Spine (Phila Pa 1976). 2000 Jun 1;25(11):1382-9. doi: 10.1097/00007632-200006010-00010. PMID: 10828920.
  21. ↑ Martimbianco ALC, PorfΓ­rio GJ, Pacheco RL, Torloni MR, Riera R. Transcutaneous electrical nerve stimulation (TENS) for chronic neck pain. Cochrane Database Syst Rev. 2019 Dec 12;12(12):CD011927. doi: 10.1002/14651858.CD011927.pub2. PMID: 31830313; PMCID: PMC6953309.
  22. ↑ Gross A, Forget M, St George K, Fraser MM, Graham N, Perry L, Burnie SJ, Goldsmith CH, Haines T, Brunarski D. Patient education for neck pain. Cochrane Database Syst Rev. 2012 Mar 14;(3):CD005106. doi: 10.1002/14651858.CD005106.pub4. PMID: 22419306.
  23. ↑ Graham N, Gross A, Goldsmith CH, Klaber Moffett J, Haines T, Burnie SJ, Peloso PM. Mechanical traction for neck pain with or without radiculopathy. Cochrane Database Syst Rev. 2008 Jul 16;(3):CD006408. doi: 10.1002/14651858.CD006408.pub2. PMID: 18646151.
  24. ↑ Patel KC, Gross A, Graham N, Goldsmith CH, Ezzo J, Morien A, Peloso PM. Massage for mechanical neck disorders. Cochrane Database Syst Rev. 2012 Sep 12;(9):CD004871. doi: 10.1002/14651858.CD004871.pub4. PMID: 22972078.
  25. ↑ Gross A, Kay TM, Paquin JP, Blanchette S, Lalonde P, Christie T, Dupont G, Graham N, Burnie SJ, Gelley G, Goldsmith CH, Forget M, Hoving JL, BrΓΈnfort G, Santaguida PL; Cervical Overview Group. Exercises for mechanical neck disorders. Cochrane Database Syst Rev. 2015 Jan 28;1:CD004250. doi: 10.1002/14651858.CD004250.pub5. PMID: 25629215.
  26. ↑ Andersen LL, Saervoll CA, Mortensen OS, Poulsen OM, Hannerz H, Zebis MK. Effectiveness of small daily amounts of progressive resistance training for frequent neck/shoulder pain: randomised controlled trial. Pain. 2011 Feb;152(2):440-446. doi: 10.1016/j.pain.2010.11.016. Epub 2010 Dec 21. PMID: 21177034.
  27. ↑ Peloso P, Gross A, Haines T, Trinh K, Goldsmith CH, Burnie S; Cervical Overview Group. Medicinal and injection therapies for mechanical neck disorders. Cochrane Database Syst Rev. 2007 Jul 18;(3):CD000319. doi: 10.1002/14651858.CD000319.pub4. Update in: Cochrane Database Syst Rev. 2015;5:CD000319. PMID: 17636629.
  28. ↑ Karjalainen K, Malmivaara A, van Tulder M, Roine R, Jauhiainen M, Hurri H, Koes B. Multidisciplinary biopsychosocial rehabilitation for neck and shoulder pain among working age adults. Cochrane Database Syst Rev. 2003;(2):CD002194. doi: 10.1002/14651858.CD002194. PMID: 12804428.
  29. ↑ Monticone M, Cedraschi C, Ambrosini E, Rocca B, Fiorentini R, Restelli M, Gianola S, Ferrante S, Zanoli G, Moja L. Cognitive-behavioural treatment for subacute and chronic neck pain. Cochrane Database Syst Rev. 2015 May 26;(5):CD010664. doi: 10.1002/14651858.CD010664.pub2. PMID: 26006174.
  30. ↑ 30.0 30.1 Lord SM, Barnsley L, Wallis BJ, McDonald GJ, Bogduk N. Percutaneous radio-frequency neurotomy for chronic cervical zygapophyseal-joint pain. N Engl J Med. 1996 Dec 5;335(23):1721-6. doi: 10.1056/NEJM199612053352302. PMID: 8929263.
  31. ↑ 31.0 31.1 31.2 Lord, Susan M.; McDonald, Gregory J.; Bogduk, Nikolai Percutaneous Radiofrequency Neurotomy of the Cervical Medial Branches, Neurosurgery Quarterly: December 1998 - Volume 8 - Issue 4 - p 288-308
  32. ↑ 32.0 32.1 32.2 McDonald GJ, Lord SM, Bogduk N. Long-term follow-up of patients treated with cervical radiofrequency neurotomy for chronic neck pain. Neurosurgery. 1999 Jul;45(1):61-7; discussion 67-8. doi: 10.1097/00006123-199907000-00015. PMID: 10414567.
  33. ↑ 33.0 33.1 Govind J, King W, Bailey B, Bogduk N. Radiofrequency neurotomy for the treatment of third occipital headache. J Neurol Neurosurg Psychiatry. 2003 Jan;74(1):88-93. doi: 10.1136/jnnp.74.1.88. PMID: 12486273; PMCID: PMC1738184.
  34. ↑ Govind J, King W, Bailey B, Bogduk N. Radiofrequency neurotomy for the treatment of third occipital headache. J Neurol Neurosurg Psychiatry. 2003 Jan;74(1):88-93. doi: 10.1136/jnnp.74.1.88. PMID: 12486273; PMCID: PMC1738184.