Cervical Radiculopathy

Contents

Search Strategy

Databases: Pubmed, Web of Science, Pedro

As subject headings varied between the databases, various combinations of the key words were used:
Cervical radiculopathy, Root compression, Epidemiology of Cervical radiculopathy, prognose for cervical radiculopathy, Cervical radiculopathy anatomy, physcial/medical management cervical radiculopathy, outcome measures for cervical radiculopathy

Definition/Description

Basic Picture of a Cervical Vertebral Body
Basic Picture of a Cervical Vertebral Body
"Cervical radiculopathy is a disease process marked by nerve compression from herniated disk material or arthritic bone spurs. This impingement typically produces neck and radiating arm pain or numbness, sensory deficits, or motor dysfunction in the neck and upper extremities."[1]

Cervical radiculopathy occurs with pathologies that causes symptoms on the nerve roots. [2] Those can be compression, irritation, traction, and a lesion on the nerve root caused by either a herniated disc, foraminal narrowing or degenerative spondylitic change (Osteoarthritic changed or degeneration) leading to stenosis of the intervertebral foramen[2] [3].

Most of the time cervical radiculopathy appears unilaterally, however it is possible for bilateral symptoms to be present if severe bony spurs are present at one level, impinging/irritating the nerve root on both sides. If peripheral radiation of pain, weakness or pins and needle are present, the location of the pain will follow back to the concerned afected nerve root [2].

Clinically Relevant Anatomy

Cervical radiculopathy is defined as a disorder affecting a spinal nerve root in the Cervical Spine, therefore a knowledge of the brachial plexus is crucial to understanding the impact of nerve root impingement or damge has on the body.


[4][5]
Anatomical illustration of the brachial plexus with areas of roots, trunks, divisions and cords marked.
Anatomical illustration of the brachial plexus with areas of roots, trunks, divisions and cords marked.


Having an understanding of anatomy is key to effective physiotherapy practice, putting this anatomy into a functional sense is even more crucial for treatment considerations and movement analysis. In the cervical spine 50% of cervical rotation occurs at the C1-2 joints (AtlantoAxial Joint) and 50% of flexion and extension occurs at the Occipitoatlanto joint. Another important consideration is that the cervical facet joints are at a 45° meaning that below C2 sideflexion is coupled with rotation to the same side[6].

We have 8 cervical nerve roots, for 7 cervical vertebrae and this may seem confusing at first. However a nerve root comes out of the spinal column between C7 and T1, hence the name C8 as T1 already exists [2].

Nerve roots and the local vessels lack a perineurium and have a poorly developed epineurium, making them vulnerable to mechanical injury when compared to the periphery. The blood supply is also less secured and vulnerable to ischemic damage[7]. These anatomical difference to peripheral nerves may explain why low pressures on the nerve root elicit large changes and S+S. The nerve roots are vulnerable to pressure damage which is why small impingements can cause S+S (Signs + Symptoms). At 5-10mmHg (0.1psi) capilliary stasis and ischemia has been observed with partial blockage of axonal transport. At 50mmhg tissue permeability increases with an influx of oedema, higher to 75mmhg, there is nerve conduction failure if sustained for 2 hours. At 70+mmhg neural ischemia is complete and conduction is not possible[7]. It is rare to get pressures that high but 5-10mmhg is a large small amount of pressure and S+S occur[7]. These pressures can occur with a less severe clinical picture in unique circumstances, if the pressure is acute then the symptoms are severe however if chronic the nervous tissue is given time to adapt and evolve to the surrounding structure and have less severe symptoms.  

Tanaka N. et al (2000) used a surgical microscope to do a anatomic study of the of the cervical intervertebral foramina, nerve roots and intradural rootlets. Their goal was to investigate the anatomy of cervical root compression. Therefor they used 18 cadavers. All soft tissue was removed and so intervertebral discs and foramina, were exposed.
The intervertrebral foramina were shaped like a funnel with the entrance zone being the most narrow part. Therefore this is the place where the compression of the nerve roots in the intervertebral foramina occures. Compression of the roots at the anterior side was ascribed to protruding discs and osteophytes of the uncovertebral region. Compression on the posterior side was caused by the superior articular process, the ligamentum flavum and the periradicular fibrous tissues. [8]

Epidemiology / Etiology

Simply defined cervical radiculopathy is a dysfunction of a nerve root in the cervical spine, as this is such a broad disorder with several mechanisms of pathology people of any age can be affected[9], with peak prominence between the ages of 40-50[2][10][11] with a reported prevelance of 83 people per 100,000 people[11]

The systematic review by Barrett et al. (2015) reported about the most impactful population based study performed in Rochester Minnesota from 1976 – 1990. The study estimated the anual incidence to be 107,3 per 100.000 for men and 63,5 per 100.000 for women. [12] These figures corresponds to the study of Radhakrishnan et al. [6]

The two main mechanisms of the nerve root irritation or impingement are:

  1. Spondylosis leading to stenosis or bony spurs - More common in older patients
  2. Disc Herniation - More common in younger patients

This rule is not correct 100% of the time but it is a good basis to go on for a logical reason: As you age, disc height decreases and there is less material within the intervertebral disc itself making a prolapse less likely and making it harder for a prolapse to impinge a nerve root.

Just think: There is more material to prolapse from a disc of a younger person!

Cervical radiculopathy (Barrett et al. 2015) is a neurological disorder from nerve root dysfunction often due to mechanical compression (because of disc hernation, stenosis, spondylosis, …). Spondylosis can affect the neuroforamen from all directions, wich limits nerve root excursion. Also cytokines released from damaged intervertebral discs can cause this disorder. [12] 

These inflammatory cytokines like interleukin-6, interleukin-8, nitric oxide, tumor necrosis factor alfa and prostaglandin E2 are involved in the development of pain associated with cervical radiculopathy and provide the rational for treatment with anti-inflammatory medications. [12]

There is increasing evidence that inflammation (Kuijper et al. 2009) in itself and/or in association with root compression is the main cause of symptoms and signs. This is proved by the presence of interleukins and prostaglandin in herniated discs and the spontaneous recovery within weeks or months in the majority of patients. [13]

The most common level of root compression is C7 (reported percentages 46.3–69%), followed by C6 (19–17.6%); compression of roots C5 (2–6.6%) and C8 (10– 6.2%) are less frequent. One possible explanation is that intervertebral foramina are largest in the upper cervical region and progressively decrease in size in the middle and lower cervical areas, with an exception of the C7-Th1 foramen (C8). [13][5]

Characteristics/Clinical Presentation

Typical Dermatomal Pattern of the Upper Limb
Typical Dermatomal Pattern of the Upper Limb

To understand the clinical presentation of cervical radiculopathy you must have a functional understanding of the clinically relevant anatomy section.

Typical symptoms of cervical radiculopathy are: irradiating arm pain corresponding a dermatomal pattern, neck pain, parasthesia, muscle weakness in a myotomal pattern, reflex impairment/loss, headaches, scapular painsensory and motor dysfunction in upper extremities and neck[2][9][3][14][15].

 At the most basic level these are the upper limb movements that are affected in the myotomal pattern.

  • C1/C2- Neck flexion/extension
  • C3- Neck lateral flexion
  • C4- Shoulder elevation
  • C5- Shoulder abduction
  • C6- Elbow flexion/wrist extension
  • C7- Elbow extension/wrist flexion
  • C8- Thumb extension
  • T1- Finger abduction

For more detailed information on the exact muscles or dermatomes that will clinically present themselves go here:

Nerve roots and the muscles affected
Dermatomal Pattern

If a nerve root is compressed it can cause a combination of factors: inflammatory mediators, changes in vascular response and intraneural oedema which causes radicular pain. Absence of radiating pain does not exclude nerve root compression. The same appears with sensory and motor dysfunction that might be present without significant pain[2].

Symptoms are generally amplified with side flexion towards the side of pain and when an extension or rotation of the neck takes place because these movements reduce the space available for the nerve root to exit the foramen causing impingement[2]. This often causes the patient to present with a stiff neck and a decrease in cervical spine range of motion (ROM) as movement may activate their symptoms. This in turn results in secondary musculoskeletal problems which can manifest as a decrease in muscle length of the cervical spine musculature (upper fibres of trapezius, scaleni, levator scapulae), weakness, joint stiffness, capsule tightness and postural defects which can go on to affect movement mechanisms of the rest of the body.

It is possible that when you are assessing a patient it may not be easy to 'bring on' the radiating arm pain, if this is the case try not to rule out radiculopathy, just try and get more information about the movements, positions or functional tasks which bring on the pain and replicate them. Reproducing the S+S (Signs and Symptoms) is a very useful tool in aiding diagnosis. Equally do not be alarmed if you cannot replicate the S+S in the assessment, give the patient exercises to do at home along with postural advice and continue to perform the activities which usually bring on the radiating arm symptoms and see if there is a change.

Differential Diagnosis

Due to the close proximity of the cervical spine vertebrae and nerve roots to the vertebral arteries it is crucial that during the initial assessment of a patient any conditions which can cause severe damage to the patients blood supply, especially during any manual therapy. It is also important to be aware of other pathologies which mimic the S+S of radiculopathy.[16]

  • Spinal Tumor
  • Systemic diseases known to cause peripheral neuropathies
  • Cervical myelopathy
  • Ligamentous Instability
  • Vertebral Artery Insufficiency (VBI)
  • Herniated nucleous pulposos (HNP)
  • Shoulder Pathology
  • Peripheral nerve disorders
  • Thoracic outlet syndrome
  • Brachial plexus pathology
  • Systemic disease
  • Parsonage-Turner syndrome


When we combine the aspects of patiënts history, physical examination and radiological findings we should be able to differentiate this from cervical radiculopathy. A negative Spurling’s test, normale range of motion of the neck and the lack of pulmonary air at the top of the lung in anteroposterior cervical radiographs could indicate a Superior pulmonary sulcus tumor. In this case such a diagnose can be confirmed with CT or MRI imaging. [17]

Diagnostic Procedures

In a non-Physiotherapy sense, the most common diagnostic methods used to assess the presence of possible compression are imaging studies (radiograph and MRI) and electrophysiologic studies (EMG + Nerve Conduction Studies) to examine the nerve root and nerve conduction velocity[18][2][9]. If either of these options have been performed on your patient then it is possible to assess and see if radiculopathy is present through commonly used Physiotherapy assessment and treatment starting with the Subjective Assessment.

Cervical radiculopathy could be confirmed when root compression is seen on MRI, which is the method of choice to detect disc protrusions. To detect foraminal stenosis which gives bony compression on the nerve, thin slices spiral CT is described as the best way to detect this.[13]

There still is no consensus on wether conventional needle myography (EMG) has a strong diagnostic value for cervical radiculopathy. Several unblinded studies reported sensitivities ranging from 30-95%.[13]

Dillingham TR et al (2001) performed a study to determine the optimal electromyography screening examination of the upper limb that ensures the detection of a cervical radiculopathy. They found that six muscle screens including paraspinal muscles yielded consistently high identification rates. The results of this study indicates that if six muscles, representing all cervical root levels, are studied, then the examiner can be confident of detecting a cervical radiculopathy.[13][19]

Kuijper B. et al (2009) nuanced this by pointing out that most C6 muscles are also innervated by C5 or C7. So according to their information, a Cervical radiculopathy at the C6 level alone will be difficult to find by the use of EMG. The use of paraspinal muscle examination seems to be more sensitive to them, but this technique is harder to perform without giving false-positive results, especially in older patiënts.[13]

Subjective Assessment

The HPC and Mechanism of Injury (Patient History) sections of a subjective assessment can be integral to diagnosis and the cause of the radiating arm pain. More frequently acute radiating arm pain is caused by a disk herniation, while chronic bilateral axial neck and radiating arm pain is usually caused by cervical spondylosis[2].

Outcome Measures

Outcome measures are an essential tool to assess whether or not you are having a positive. negative or static effect on a patients' condition. Cervical Radiculopathy is no different. There are a lot of outcome measures in existance and it is important to know if the tool you are using is measuring what you want to measure (Specificity) and how good it is correctly identifying a pattern (Sensitivity)[20].Finally, the test or scale should actually be able to test change over time in whatever is being tested (Responsiveness).

NDI (Neck disability index)

Vernon H et al. (1991) and many others stated that the NDI is a reliable and valid measurements tool in patients with neck pain.[21] In their systematic review of the literature, Macdermid JC et al. (2009) used 37 published studies to conclude that there is enough evidence to support the NDI as a very good self-report measure for neck pain.[22]

Moeti P., et al (2001) reported the NDI as an outcome measure for patients with a cervical radiculopathy. She concluded that further research is necessary to determine whether the NDI is a good outcome measurements tool for a group of patients with this specific pathology. The NDI has been reported as an outcome measure among patients with cervical radiculopathy, yet the reliability and validity of the measure in this patient population remains unknown. [23]

Patient Specific Functional Scale (PSFS)

Joshua A. et al (2006) wanted to examine the test-retest reliability, construct validity, and minimum levels of detectable and clinically important change for the Neck Disability Index (NDI) and Patient Specific Functional Scale (PSFS). Their conclusion was that the PSFS had superior reliability, construct validity, and responsiveness in patients with cervical radiculopathy compared to the NDI. But they stated that further research was needed.[24]

Numerical Pain Rating Scale (NPRS)

The NPRS is used to capture a patients pain during the previous 24 hours. This has been shown to have adequate reliability, validity, and responsiveness in patients with low back pain.[25] It still needs to be examined in patients with neck pain. Therefore Joshua A. et al (2006) compared the NPRS with the NDI and the PSFS (Patient Specific Functional Scale). And they found that the NDI was a better way to examine outcome measures in patients with cervical radiculopathy. [24]

NDI (Neck disability index) + Patient Specific Functional Scale (PSFS) + Numerical Pain Rating Scale (NPRS)

Young IA. et al (2010) wanted to examine the psychometric properties of the Neck Disability Index, Patient-Specific Functional Scale, and the Numeric Pain Rating Scale in a cohort of patients with cervical radiculopathy. All three outcome measures showed adequate responsiveness in this patient population. In light of the varied distribution of symptoms in patients with cervical radiculopathy, future studies should investigate the psychometric properties of other neck-related disability measures in this patient population.[26]

Neck Pain and Disability Scale (NPAD)

Goolkasian et al (2002) investigated test–retest reliability and construct validity for the Neck Pain and Disability Scale (NPAD). They concluded that the NPAD is a stable and responsive measure for patients with neck pain. The Neck Pain and Disability Scale factor scores are useful in identifying treatment effects on the specific dimensions involved in the pain experience.[27]

Examination

Cervical examination is nessecary to diagnose the patiënt with cervical radiculopathy. Provocative tests are performed to provoke or worsen the symptoms in the affected arm and are indicative of cervical radiculopathy.[13]

In 2003, Dr. Robert Wainner and colleagues examined the accuracy of the clinical examination and developed a clinical prediction rule to aid in the diagnosis of cervical radiculopathy.  Their research demonstrated that these 4 clinical tests, when combined, hold high diagnostic accuracy compared to EMG studies:  Positive tests for Spurlings TestUpper limb tension-1 Distraction test and  Cervical Flexion Rotation Test. When all 4 of these clinical features are present, the post-test probablity of cervical radiculopathy is 90%, if only three of the four test are positive the probability decrease to 65%[28] [3][9][29]. Another combination of tests, with good reliability are the combination of the Spurlings Test, Neck Distraction, Valsalva and Upper Limb Tension Tests 12a and 2b[30].

Tong HC et al. (2002) did a cross-sectional study to determine the sensitivity and specificity of the Spurling Test for cervical radiculopathy. Between 1988 and 1993 they examined 255 patiënts who were were referred for electrodiagnosis of upper extremity nerve disorders. They performed the Spurling test before the imaging was done. The test had a sensitivity of 30% and a specificity of 93%. They concluded that the Spurling test is not sensitive but is yet very specific for cervical radiculopathy. So this test is not useful as a screening test but it can well be used to confirm a cervical radiculopathy. [31]

Miller JK (2014) described the Spurling test as the shoulder abduction relief test. The shoulder abduction sign is used to detect cervical radicular pathology. The test is a common part of most chiropractic curricula under another synonym: Bakody's test and is commonly used in chiropractic practice. The shoulder abduction test is performed by asking the patient to place their hand on top of their head. This can be performed using the asymptomatic arm first to help establish a baseline finding for the side assumed to be normal. This would be followed by alternately placing the hand of the symptomatic side on top of the head. For the sake of efficiency, both hands could be placed on the top of the head simultaneously. [32]

Sidney M. et al (2006) performed a systematic review in which they compared 6 provocative tests for cervical radiculopathy. They said that provocative tests might as well be helpful to establish a diagnose in patients with a suspected cervical radiculopathy. Especially when the patient lacks clear neurological dificits. According to them a positive Spurling’s test, as well as positive findings for traction/ neck distraction, and the Valsalva’s manoeuvre might be suggestive for a cervical radiculopathy, when this is consistent with the history and physical findings. These tests have a high specificity. A negative Upper Limb Tension Test (ULTT) might be used to rule out a cervical radiculopathy, because of its high sensitivity.[33]

There’s a lack of studies investigating the accuracy of these tests, as well as the heterogenity between the various studies and the numerous methodological problems. Thus we can’t do any strong recommandations for these tests, especially in the primary care setting. So these tests need to be interpreted with caution and further high level studies are needed. [33]

According to John M. Caridi (2011), sensory examination can distinguish between a C8 radiculopathy and ulnar neuropathy, as there will be splitting of the hyperalgesia in either the third or fourth digit with ulnar neuropathy. With C8 radiculopathy, the entire digit will be affected. Motor examination may or may not show a grade of weakness in the myotome that corresponds to the pathologic nerve. No myotome corresponds to the upper four cervical nerve roots. C5 radiculopathy may show weakness in the deltoids (evaluated by testing for shoulder abduction); C6 will show weakness in the biceps and flexor carpi ulnaris (evaluated by testing for wrist extension); C7 weakness occurs in the triceps, as well as the brachioradialis (evaluated by testing for ellbow extension); C8 pathology causes weakness in the intrinsic muscles of the hand, as evaluated by finger abduction and grip. Muscle stretch reflexes also tend to be decreased in the setting of radiculopathy. Biceps hyporeflexia is indicative of C6 radiculopathy, while decrease in the triceps and brachioradialis reflexes corresponds to pathology at C7. The neurologic examination has moderately strong intraobserver reliability with a kappa value between 0.4 and 0.64 according to Viikari-Juntura(1989). [34][35]

Medical Management

There are several intervention strategies for managing cervical radiculopathy with physical therapy and surgical interventions being the most common.  Long-term benefits of surgical interventions are questionable with reported numbers of 25% of people continuing to experience pain and disability at 12 month follow-ups[36].  There is a significant amount of evidence available to support the use of physical therapy interventions[37] for patients with cervical radiculopathy, and the benefit of physical therapy and manual techniques in general for patients with neck pain with or without radicular symptoms (see key evidence for a list of references).

Indications for a single level surgery are [38]:
• Sensory symptoms (radicular pain and / or paresthesias) in a dermatomal distribution that correlates with involved cervical level.
AND

     • Motor deficit, reflex changes or positive EMG correlated to involved cervical level

     OR
     • A positive response to a selective nerve root block (SNRB).
AND
• Positive MRI or myelogram with computed tomography (CT) scan.
AND
• At least 6 weeks of conservative care such as physical therapy, epidural injections, NSAID’s, pain killers, … .
• In case of clear motor deficit, 6 weeks of conservative care are not required.

Critria for a 2-level srugery are:
• All of the criteria previously described for a single level surgery, not including SNRB, are present at the primary level.
AND
     • The adjacent level has radicular pain correlating with at least moderate foraminal stenosis or lateral recess herniation
     OR
     • EMG changes, motor deficits or reflex changes correlated to adjacent level.

Operative techniques that are frequently used as treatment for cervical radiculopathy are: Anterior Cervical Dissectomy (=decompression) (ACD), Anterior Cervical Dissectomy and Fusion (ACDF), Total Disc Arthroplasty (TDA), laminotomy, foraminotomy, corpectomy. [39][38]

Engquist M et al. (2013) found that surgery with physiotherapy resulted in a more rapid improvement during the first postoperative year, with significantly greater improvement in neck pain and the patient's global assessment than physiotherapy alone. The differences between the groups decreased after 2 years. He suggested that structured physiotherapy should be tried before surgery is chosen.[40] Persson et al. (1997) concluded that there were no long term (1 year) differences between surgery (ACD) and physical therapy in strength, pain and sensation.[41] Several other studies prove that physical / social functioning and pain significantly improved after surgery (ACD), although these improvements remained relatively short termed (max 1 year) and diminished after a longer period (1 to 4 years). Outcome measures as quality of life (QoL) and range of motion (RoM) were not included in this last study.[39]

ACDF is associated with diminished ROM & strength compared to conservative treated subjects. This can, occasionally, be associated with prolonged pain. [39]

Peolsson A et al. (2013) concluded that ACDF did not result in additional improvements in neck active range of motion, neck muscle endurance, or hand-related function compared with a structured physiotherapy program alone in patients with cervical radiculopathy.
The article suggests that a structured physiotherapy program should precede a decision for ACDF intervention in patients with cervical radiculopathy, to reduce the need for surgery. [42]

Abbott et al. (2013) found that the use of a rigid cervical collar during 6 post-operative weeks after ACDF is associated with significantly lower levels of neck disability index after 6 weeks and significantly lower levels of prospective neck pain. Abbott et al. (2013) suggests that the use of a cervical collar may help some patients to cope with initial post-operative pain and disability. Further studies are required to investigate health-related QoL in patients with and without rigid collar use after ACDF.[43]

Short duration of pain, female sex, low health quality, high levels of anxiety due to neck/arm pain, low self-efficacy, and a high level of distress before treatment were associated with better outcome from surgery.[40]

The nonoperative treatment includes a period (+/- one week, not more) of immobilisation with a cervical collar to decrease the compression on the nerve root; cervical traction; medication to reduce the pain; physical therapy and manipulation including massage, stretching, exercices to improve range of motion and eventually ice, heat and electrical stimulation. They must be used together and not separately to show improvement. But all these elements of the treatment need further studies to prove more effectiveness. [2]

Conservative treatment without the use of a cervical collar results in a faster functional rehabilitation compared to treatment with a cervical collar for a period of 3 months. [41] In patients with extreme pain sensations a cervical collar could be beneficial, although surgery or epidural corticosteroid injections are probably more efficient solutions.

Epidural steroid injections can also be used as treatment for cervical radiculopathy. The injections are given under guidance of fluoroscopy or CT. There is limited evidence that transforaminal epidural steroid injections provide relief for 60% of the patients and about 25% of the patients with clear surgical indications. Steroid injections are not a causal treatment and do not “solve” the patient’s problem. It can be considered when developing a medical/interventional treatment plan for patients with cervical radiculopathy from degenerative disorders. Transforaminal injections are not without risk and possible complications such as spinal cord injury and death must be considered before performing this procedure. [44][45]

Lee SH et al. (2012) researched the use of ESI (Epidural Steroid Injections) in patients diagnosed with cervical soft disc or hard disc causing nerve root compression and symptoms. In more than 80% of patients with CR who were surgical candidates, surgery was avoided using ESI. The significant factors predisposing failure of ESI were intensity of symptom and a previous episode of CR. [46] Important nuance, all patients in this study suffered from cervical radiculopathy due to disc pathology.

Persson LC et al. (1997) demonstrates the favourable spontaneous course of cervical radiculopathy. [41]

Physical Therapy Management

Although a definitive treatment progression for treating cervical radiculopathy has not been developed, a general consensus exists within the literature that using manual therapy techniques in conjunction with therapeutic exercise is effective in regard to increasing function, as well as active range of movement (AROM), focusing on decreasing levels of pain and disability will most likely be the main focus of the patient[47].Recent high level research confirms the positive outcomes of exercise therapy. (Cheng CH et al. LoE: 1A) [37]

If the patient has had long-term pain, an element of pain sensitisation may have developed and chronic pain behaves differently to acute pain. Therefore education about pain and reconceptualisation may be necessary. 

Treatment Options:

  1. Education and Advice
  2. Manual Therapy - PAIVMs (Passive Assessory Intervertebral Movements) / PPIVMs (Passive Physiological Intervertebral Movements) / NAGs (Natural Apophyseal Glides) / SNAGs (Sustained Natural Apophyseal Glides)
  3. Exercise Therapy - AROM, stretching and strengthening
  4. Postural Re-Education

Education and advice

Education is key to getting the patient on your side and to work co-operatively with Physiotherapy. If a patient understands why they are having the neck pain which is causing them to have arm pain then they will more likely want to take part in rehabilitation. If they do not understand what the point in this 'exercise' or this 'pressing' then they will likely think it to be a waste of time. This is a generalisation of course but it is often accurate. 

An important piece of advice to rehabilitation from a prolapsed disc, is that tabacco smoking causes constriction of the vascular network surrounding the intevertebral disc (IVD), thus reduces the indirect exchange of nutrients and anabolic agents from the blood vessels to the disc. Nicotine down-regulates the proliferation rate and glycosaminoglycan (GAG) biosynthesis of disc cells. Nicotine mostly affects the GAG concentration at the cartilage endplate, reducing it up to 65% of the value attained in normal physiological conditions. Tabacco mostly affects the nucleus pulposus, whose cell density and GAG levels reduce up to 50% of their normal physiological levels. The effectiveness of quitting smoking on the regeneration of a degenerated IVD shows limited benefit on the health of the disc. A cell-based therapy in conjunction with smoke cessation should provide significant improvements in disc health, suggesting that, besides quitting smoking, additional treatments should be implemented in the attempt to recover the health of an IVD degenerated by tobacco smoking. (Elmasry S et al. LoE: 4) [48] Additionally it is always good to bring up the topic of smoking cessation with patients for their all round health, tying in with Holistic Management.

Manual Therapy

There are some contradictions in the literature about manual therapy techniques. According to Gross AR et al (2004, LoE: 2B) mobilization and/or manipulation when used with exercise are beneficial (pain relief and improvement of function) for persistent mechanical neck disorders with or without headache. Done alone, manipulation and/or mobilization were not beneficial. Compared to one another, neither was superior. There was insufficient evidence available to draw conclusions for neck disorder with radicular findings. So further research is necessary.[49]

Fritz JM and colleagues (2014, LoE: 1B) examined the effectiveness of cervical traction in addition to exercise in patients with cervical radiculopathy. Adding mechanical traction to exercise for patients with cervical radiculopathy resulted in lower disability and pain, particularly at long-term follow-ups. [50]

In a multimodal treatment model, the addition of manual therapy techniques (thought to increase the size of the intervertebral foramen of the affected nerve root) has no significant additional benefits according to Langevin P et al. (2015, LoE: 1B) [51] and Young IA et al. (2009, LoE: 1B) [26].

Jellad A. et al (2009, LoE: 3B) concluded that manual or mechanical cervical traction can be a major contribution in the rehabilitation of CR particularly if it is included in a multimodal approach of rehabilitation. [52]

Furthermore, cervical spine manipulation carries a risk of complications like vertebral dissection and spinal cord compression because of massive disc herniation. Therefore, this intervention should be discouraged in cervical radiculopathy, especially if imaging of the spine has not yet been performed.(Kuijper B. et al, 2009. LoE: 2A) [13]

In a recent systematic review by Boyles et al in 2011(LoE:1A)[53], manual therapy was shown to be effective at reducing pain levels, improving function and increasing joint ROM. When combined with exercise therapy it was more effective than the control group of manual therapy or exercise therapy however both control groups were effective at reducing signs and symptoms[54].

The manual therapy techniques proven to be effective by the systematic review were:

  • Thrust mobilisations of the cervical or thoracic spine
  • Cervical non-thrust mobilisations: PA glides/Lateral Glides (in ULTT1 position) /Rotations/Retractions

The parameters were recorded in a study by Ragonese et al[54]; performing one set of 30 seconds or 15-20 repetitions at each desired level of the cervical spine at grade 3 or 4[55](Mobilisations). Others stated that it was down to the practitioners discgression.(e.g. 30–45 seconds for all segments C2 through C7 at each treatment session)

In a recent systematic review Cross KM and collegues (2011, LoE: 2A) concluded that thoracic spine thrust manipulation may provide short-term improvement in pain, range of motion, and self-reported functioning in patients with acute or subacute mechanical neck pain. Further research is necessary. [56]

Overall a study by Persson et al[41] highlighted that there was no significant difference between outcome measures of patients who had had surgery, physiotherapy or cervical collar explaining that physiotherapy is at least as effective as surgery.

When performing manual therapy on the neck it is important to to be aware of any potential risk factors such as arterial insufficiency, Hypertension, Craniovertbral ligament insufficiency and upper motor neurone disorders[57].

Muscle Energy Techniques

Cleland et al[58] utilised muscle energy techniques (MET) in 28 patients, 46% recieving positive outcomes, however details of the techniques used were insufficient and a variety of techniques were used as it was down to the practitioner to decide which technique would be used.

The quality of research related to testing the effectiveness of MET is poor. Studies are generally small and at high risk of bias due to methodological deficiencies. (Franke H et al., 2015, LoE: 1A)[59]

Neurodynamics - Gliding and Sliding/Tensioning

Neural dynamic techniques were included as treatments in these two articles.[60][58]
Ragonese (2009)[60]

Another study[54] performed the neurodynamics sliding and tensioning techniques, outlined by Butler[61], whilst having the patient in an upper limb tension positions described by Magee[62]conducted in a slow and oscillatory fashion. With improvement in symptoms, the technique was progressed to a ‘tension’ technique, also described by Butler.[61] Again having positive outcomes in regards to pain and function.Treatment duration was not recorded.

In the Cleland et al.’s article, (2007, LoE:4) [58] 23 patients either received neural dynamic techniques or neural mobilizations, of which 13 patients (56,5%) had a successful outcome. Exact treatment parameters, the nerve mobilized, the manner of which the mobilization occurred and the length of time the technique performed were not described in the article.

Exercise Therapy

Recent high level research confirms the positive outcomes of exercise therapy. (Cheng CH et al. LoE: 1A) [37]

Exercises targeted at opening the intervertebral foramen are the best choice for reducing the impact of radiculopathy. Exercises such as contralateral rotation and sideflexion are amongst the simplest forms of exercises which are effective against signs and symptons, given in the form of active ROM[51](2012, LoE: 2B). Due to the intricate and close relationship of muscles on the intervertebral foramen and the likely presentation of reduced ROM, stretching is also an effective form of treatment to regain ROM[63](2013, LoE: 5).

Once ROM increases strengthening can also be utilised to create new stability and reduce the risk of developing nerve root irritation in the future, as long as it is not caused by a structure which cannot be influenece by physiotherapy. During the initial stages of treatment, strengthening should be limited to isometric exercises in the involved upper limb. Once the radicular symptoms have been resolved, progressive isotonic strengthening can begin. This should initially stress low weight and high repetitions (15-20 repetitions). Closed kinetic chain activities can be very helpful in rehabilitating weak shoulder girdle muscles. However, a multicenter randomized controlled trial found no significant difference with the addition of specific neck stabilization exercises to a program of general neck advice and exercise(Griffiths C et al., 2009, LoE: 2B) [64]

Patient should be instructed to remain as active as possible and perform exercises daily on the days between therapy sessions. Written exercise instructions should therefore be available. We suggest a 2 components program, as suggested by Fritz JM et al. (2014, LoE: 1B). 2 components: scapula strengthening and cervical strengthening.

Cervical strengthening exercises should include supine craniocervical flexion to elicit contraction of the deep neck flexor muscles without contraction of superficial neck muscles (Falla D et al., 2013, LoE 1B)[65]. Feedback using an air-filled pressure sensor or tactile cues can be useful. Patient should perform three sets of 10 contractions of 10 seconds with proper muscle activation. Craniocervical flexion contractions were also performed with the patient seated, with the goal of 30 repetitions of 10-second contractions.

Scapular retraction against resistance using elastic bands or pulleys can be added. Scapular-strengthening exercises included prone horizontal abduction, sidelying forward flexion, prone extension of each shoulder, as well as prone push-ups with emphasis on shoulder protraction. The goal was 3 sets of 10 repetitions, with resistance added as tolerated.

Prognosis

Regarding physical therapy interventions, in 2007 Joshua Cleland and colleagues (LoE: 4)[58] examined the predictors of positive short-term outcomes in people with a clinical diagnosis of cervical radiculopathy.  The following clinical features were found to be most predictive of a positive short-term outcome:

  • Age <54
  • Dominant arm not affected
  • Looking down does not worsen symptoms
  • Treatment involves manual therapy, cervical traction, and deep neck flexor strengthening for at least 50% of visits

If 3 of these features are present, the probability of success is 85%, and increases to 90% if all 4 are present[66]

Key Research

The following articles are key evidence pieces for physical therapy interventions as they relate to both cervical radiculopathy and neck pain in general:

  • Manual therapy compared to 'usual' physical therapy and general practitioner care[67][50]
  • Manual therapy compared to conservative therapy management [40][42]
  • Prognostic factors for neck pain in the general population[68][58]
  • Immediate effects of thoracic manipulation for patients with neck pain[69][56]
  • Clinical prediction rule for thoracic manipulation in patients with neck pain[70]
  • Clinical guidline for surgery indications in patients with CR [38]

Clinical Bottom Line

Cervical radiculopathy is defined as a disorder (compression, traction, irritation, herniated disk, …) affecting a spinal nerve root in the cervical Spine. Cervical radiculopathy typically produces neck and radiating arm pain, numbness, sensory deficits, or motor dysfunction in the neck and upper extremities. It is important to have knowledge of the cervical anatomy, because it is the key to effective physiotherapy practice and treatment.

Because there are other pathologies that have the same signs and symptoms of radiculopathy, it’s recommended to do a good examination. You can use imaging studies (MRI) or electro physiologic studies(EMG + Nerve Conduction Studies) [71][1][26]. Better, is to use these 4 clinical tests: Spurlings Test, Upper limb tension-1 Distraction test and Cervical Flexion Rotation Test. When all 4 of these clinical test are positive, the post-test probability of cervical radiculopathy is 90%.

The main focus for physical therapy or medical management of cervical radiculopathy, is decreasing the pain and disability. Once the treatment is started, it’s important to choose the right tool to evaluate your patient. The Neck disability index is a good option.

Recent Related Research (from Pubmed)

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