Cervical Collar: Difference between revisions

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<u>''''Note:'''</u>'''&nbsp; Even though the term "Cervical Collar" has widely been used, the standarised and universally accepted term will be Cervical Orthosis. The name should be given depending on the parts of the body the orthotic device supporting. For example Cervical Orthosis, Head Cervical Orthosis, Cervico Thoracic Orthosis , etc.'''  
<u>''''Note:'''</u>''' Even though the term "Cervical Collar" has widely been used, the standarised and universally accepted term will be Cervical Orthosis. The name should be given depending on the parts of the body the orthotic device supporting. For example Cervical Orthosis, Head Cervical Orthosis, Cervico-Thoracic Orthosis , etc.'''  


== Types  ==
== Types  ==


Based on the materials and the hardness of the material the cervical collars can be classified in to&nbsp;
Based on the materials and the hardness of the material the cervical collars can be classified into...
 
#Soft collar  
#Soft collar  
#Rigid collar
#Rigid collar
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=== Rigid collar ===
=== Rigid collar ===


[[Image:Rigid collar 1.jpg|left]]The rigid collars are similar to the soft collars but they are made out of plexiglass. They are easily applied and are easy to keep clean, an advantage of the plastic collar. This type of collar also has different sizes which has to fit the patient. These collars restrict a certain motion (not strictly) in flexion and extension.<ref name="Sandler">Sandler AJ. The effectiveness of various cervical orthoses: an in vivo comparison of the mechanical stability provided by several widely used models. Spine. 1996; 21(14): 1624-1629. (LEVEL 1B)</ref> They support the chin but also the occiput, this reduces the extension possibilities, especially in the end phase. A drawback of the rigid collars is that they potentially cause venous outflow obstruction, which might elevate intracranial pressure.<ref name="Davies">Davies G et al. The effect of a rigid collar on intracranial pressure. Injury. 1996; 27(9): 647-649. (LEVEL 2B)</ref><ref name="Mobbs">Mobbs RJ et al. Effect of cervical hard collar on intracranial pressure after head injury. ANZ Journal of surgery. 2002; 72: 389-391. (LEVEL 2B)</ref> If there is a clear evidence of an increased intracranial pressure, the collar should be removed or repositioned.<ref name="Ho">Ho A MH. et al. Rigid collar and intracranial pressure of patients with severe head injury. Journal of Trauma. 2002; 53: 1185-1188. (LEVEL 2B)</ref><br>  
[[Image:Rigid collar 1.jpg|left]]The rigid collars are similar to the soft collars but they are made out of plexiglass. They are easily applied and are easy to keep clean, an advantage of the plastic collar. This type of collar also has different sizes which has to fit the patient. These collars restrict a certain motion (not strictly) in flexion and extension.<ref name="Sandler">Sandler AJ. The effectiveness of various cervical orthoses: an in vivo comparison of the mechanical stability provided by several widely used models. Spine. 1996; 21(14): 1624-1629. (LEVEL 1B)</ref> They support the chin but also the occiput, this reduces the extension possibilities, especially in the end phase. A drawback of the rigid collars is that they potentially cause venous outflow obstruction, which might elevate intracranial pressure.<ref name="Davies">Davies G et al. The effect of a rigid collar on intracranial pressure. Injury. 1996; 27(9): 647-649. (LEVEL 2B)</ref><ref name="Mobbs">Mobbs RJ et al. Effect of cervical hard collar on intracranial pressure after head injury. ANZ Journal of surgery. 2002; 72: 389-391. (LEVEL 2B)</ref> If there is a clear evidence of an increased intracranial pressure, the collar should be removed or repositioned.<ref name="Ho">Ho A MH. et al. Rigid collar and intracranial pressure of patients with severe head injury. Journal of Trauma. 2002; 53: 1185-1188. (LEVEL 2B)</ref><br>  
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In general the collar should be worn constantly for one week. After that the use of the collar should be gradually decreased. If the collar is worn for a longer period, it could have several effects such as: soft tissue contracture, muscular atrophy, loss of proprioception and coordination but also psychological dependence.<ref name="Lieberman">Lieberman JS: Cervical soft tissue injuries and cervical disc disease. In Principles of Physical Medicine and Rehabilitation in the Musculoskeletal Diseases, Grune, New York, 1986: 263-286.</ref> This means that the patient will have the feeling that he needs the collar for a safe feeling even though it isn’t necessary.  
In general the collar should be worn constantly for one week. After that the use of the collar should be gradually decreased. If the collar is worn for a longer period, it could have several effects such as: soft tissue contracture, muscular atrophy, loss of proprioception and coordination but also psychological dependence.<ref name="Lieberman">Lieberman JS: Cervical soft tissue injuries and cervical disc disease. In Principles of Physical Medicine and Rehabilitation in the Musculoskeletal Diseases, Grune, New York, 1986: 263-286.</ref> This means that the patient will have the feeling that he needs the collar for a safe feeling even though it isn’t necessary.  


<span style="line-height: 1.5em;">Several studies are doubtful about the efficiency of the neck collar compared to early mobilizations. They both reduce the pain </span>'''but the early mobilizations show a greater improvement in cervical range of motion'''<span style="line-height: 1.5em;">.</span><ref name="Mealy" /><ref name="McKinney">McKinney. Early mobilization and outcome in acute sprains of the neck. British Medical Journal. 1989; 299: 1006-1008. (LEVEL 1B)</ref><span style="line-height: 1.5em;"> Another study shows no differences between the two interventions.</span><ref name="Pennie">Pennie and Agambar. Whiplash injuries. A trial of early management. Journal of Bone and Joint Surgery. 1990; 72B: 277-279. (LEVEL 2B)</ref>  
Several studies are doubtful about the efficiency of the neck collar compared to early mobilizations. They both reduce the pain '''but the early mobilizations show a greater improvement in cervical range of motion'''.<ref name="Mealy" /><ref name="McKinney">McKinney. Early mobilization and outcome in acute sprains of the neck. British Medical Journal. 1989; 299: 1006-1008. (LEVEL 1B)</ref> Another study shows no differences between the two interventions.<ref name="Pennie">Pennie and Agambar. Whiplash injuries. A trial of early management. Journal of Bone and Joint Surgery. 1990; 72B: 277-279. (LEVEL 2B)</ref>  


<span style="line-height: 1.5em;">It has to be said that the collars do not strictly immobilize the neck, they mostly control pain when used for limited periods of time. A use for longer than two weeks should be discouraged because of the side effects (atrophy and shortening of the neck musculature, soft tissue contractions, thickening of subscapular tissues). The most important effect is the increased dependence of the patient and the enhancement of feelings of disability. This will lead to a longer use of the collar by the patient and will strengthen all the disadvantages.&nbsp;</span>
It has to be said that the collars do not strictly immobilize the neck, they mostly control pain when used for limited periods of time. A use for longer than two weeks should be discouraged because of the side effects (atrophy and shortening of the neck musculature, soft tissue contractions, thickening of subscapular tissues). The most important effect is the increased dependence of the patient and the enhancement of feelings of disability. This will lead to a longer use of the collar by the patient and will strengthen all the disadvantages.  


== Comparison  ==
== Comparison  ==


When different types of cervical collar are compared with respect to mechanical stability (both actively and passively), all collars restrict motion to some extent. The collars ranked from least restrictive to most restrictive: soft collar, Philadelphia collar, SOMI.<ref name="Sandler" /><ref name="Gavin">Gavin TM et al. Biomechanical analysis of cervical orthoses in flexion and extension: a comparision of cervical collars and cervical thoracic orthoses. Journal of rehabilitation research and development. 2003; 40(6): 527-537. (LEVEL 2B)</ref> Although, it has to be said that the differences were not usually large. In general the collars do not provide a high level of mechanical restriction of motion and is variably between people.<ref name="Sandler" />  
When different types of cervical collar are compared with respect to mechanical stability (both actively and passively), all collars restrict motion to some extent. The collars ranked from least restrictive to most restrictive: soft collar, Philadelphia collar, SOMI.<ref name="Sandler" /><ref name="Gavin">Gavin TM et al. Biomechanical analysis of cervical orthoses in flexion and extension: a comparison of cervical collars and cervical thoracic orthoses. Journal of rehabilitation research and development. 2003; 40(6): 527-537. (LEVEL 2B)</ref> Although, it has to be said that the differences were not usually large. In general the collars do not provide a high level of mechanical restriction of motion and is variably between people.<ref name="Sandler" />  


The soft and rigid collar show no significant differences in movement for the most daily activities. This is because the ADL require only a small percentage of the total range of motion.<ref name="Miller">Miller, C et al. Soft and rigid collars provide similar restriction in cervical range of motion during fifteen activities of daily living. Spine, volume 35, number 13, 2010. p 1271-1278. (LEVEL 1B)</ref> Both collars can be used for people who are in less pain but need the collar to immobilize the neck and for a sense of security. In this case, the collars act primarily as proprioceptive guides to regulate the movement of the cervical spine rather than as a restraint to physically impede motion.<ref name="Miller" /><br>  
The soft and rigid collar show no significant differences in movement for the most daily activities. This is because the ADL require only a small percentage of the total range of motion.<ref name="Miller">Miller, C et al. Soft and rigid collars provide similar restriction in cervical range of motion during fifteen activities of daily living. Spine, volume 35, number 13, 2010. p 1271-1278. (LEVEL 1B)</ref> Both collars can be used for people who are in less pain but need the collar to immobilize the neck and for a sense of security. In this case, the collars act primarily as proprioceptive guides to regulate the movement of the cervical spine rather than as a restraint to physically impede motion.<ref name="Miller" />


== Treatment cervical radiculopathy: evidence studies showing effectiveness of&nbsp;the cervical collar&nbsp;<br> ==
== Treatment cervical radiculopathy: evidence studies showing effectiveness of the cervical collar  ==


Cervical collar and rest or physiotherapy and home exercises were compared with wait and see policy for patients with [http://www.physio-pedia.com/index.php5?title=Cervical_Radiculopathy cervical radiculopathy] over a period of 6weeks.  
Cervical collar and rest or physiotherapy and home exercises were compared with wait and see policy for patients with [http://www.physio-pedia.com/index.php5?title=Cervical_Radiculopathy cervical radiculopathy] over a period of 6 weeks.  


The cervical collar was semi-hard, comfortable and in six different sizes. Patients had to wear it during the first 3 weeks the whole day while also taking as much rest as possible. During the 3 last weeks, they had to decrease the time of wearing a collar a day. After 6 weeks they had to stop wearing it.&nbsp;Physiotherapy included exercises for mobilization and stabilization of cervical spine, and reinforcing superficial and deep neck muscles. Patients had also exercises to do at home.&nbsp;For the wait and see policy patients were asked to continue daily activities as much as possible.  
The cervical collar was semi-hard, comfortable and in six different sizes. Patients had to wear it during the first 3 weeks the whole day while also taking as much rest as possible. During the 3 last weeks, they had to decrease the time of wearing a collar a day. After 6 weeks they had to stop wearing it.&nbsp;Physiotherapy included exercises for mobilization and stabilization of cervical spine, and reinforcing superficial and deep neck muscles. Patients had also exercises to do at home.&nbsp;For the wait and see policy patients were asked to continue daily activities as much as possible.  


Results show that arm and neck pain were significantly reduced with the collar and physiotherapy in comparison to the wait and see policy. The results for the neck disability index show a significantly improvement for the collar, while the physiotherapy showed the same pattern but wasn’t significant compared to the wait and see policy.&nbsp;
Results show that arm and neck pain were significantly reduced with the collar and physiotherapy in comparison to the wait and see policy. The results for the neck disability index show a significantly improvement for the collar, while the physiotherapy showed the same pattern but wasn’t significant compared to the wait and see policy.


Better results for cervical collar and physiotherapy can be explained thus: cervical collar decreases the (foraminal) compression and inflammation of the nerve root by immobilization, this causes a reduced arm and neck pain. On the other hand, physiotherapy wants to regain the range of motion and strength of the neck musculature so that musculoskeletal problems are avoided. The pain reduction is still unclear.<br>We can conclude that a semi-hard cervical collar and rest, or physiotherapy and home exercises are effective for short term (6weeks) reduction of pain for patients with cervical radiculopathy in comparison with wait and see policy.&nbsp;
Better results for cervical collar and physiotherapy can be explained thus: cervical collar decreases the (foraminal) compression and inflammation of the nerve root by immobilization, this causes a reduced arm and neck pain. On the other hand, physiotherapy wants to regain the range of motion and strength of the neck musculature so that musculoskeletal problems are avoided. The pain reduction is still unclear.<br>We can conclude that a semi-hard cervical collar and rest, or physiotherapy and home exercises are effective for short term (6 weeks) reduction of pain for patients with cervical radiculopathy in comparison with wait and see policy.


This has been studied over a period of 6 weeks. 205 patients (aged between 18-75) were randomly divided into 3 groups: a group with a semi-hard collar and rest, a group with physiotherapy and home exercises and a control group. Patients had to show the symptoms of cervical radiculopathy since less than one month, arm pain on VAS of 40mm or more, radiation of arm pain distal to elbow, at least one of provocation arm pain by neck movements, sensory changes in dermatomes, diminished deep tendon reflexes, muscle weakness in myotome. The results were taken at entry, after 3 and 6 weeks follow-up and after 6 month follow-up. Primary outcome measures were VAS for neck and arm pain and the neck disability index.<ref name="Kuijper">Kuijper B et al. Cervical collar or physiotherapy versus wait and see policy for recent onset cervical radiculopathy : randomised trial. BMJ. 2009;1-7. (LEVEL B)</ref>  
This has been studied over a period of 6 weeks. 205 patients (aged between 18-75) were randomly divided into 3 groups: a group with a semi-hard collar and rest, a group with physiotherapy and home exercises and a control group. Patients had to show the symptoms of cervical radiculopathy since less than one month, arm pain on VAS of 40mm or more, radiation of arm pain distal to elbow, at least one of provocation arm pain by neck movements, sensory changes in dermatomes, diminished deep tendon reflexes, muscle weakness in myotome. The results were taken at entry, after 3 and 6 weeks follow-up and after 6 month follow-up. Primary outcome measures were VAS for neck and arm pain and the neck disability index.<ref name="Kuijper">Kuijper B et al. Cervical collar or physiotherapy versus wait and see policy for recent onset cervical radiculopathy : randomised trial. BMJ. 2009;1-7. (LEVEL B)</ref>  


== Clinical Bottom Line&nbsp;<br> ==
== Clinical Bottom Line  ==


The take home message is even thogh the cervical orthoses are effective for short term pain relief , this cannot used as an alternative to Physiotherapy program. However, if used and weaned appropriately, the cervical orthoses can be an effective adjunct to the patient's treatment program.  
The take home message is even though the cervical orthoses are effective for short term pain relief, this cannot used as an alternative to Physiotherapy program. However, if used and weaned appropriately, the cervical orthoses can be an effective adjunct to the patient's treatment program.  


== Recent Related Research (from [http://www.ncbi.nlm.nih.gov/pubmed/ Pubmed])  ==
== Recent Related Research (from [http://www.ncbi.nlm.nih.gov/pubmed/ Pubmed])  ==
<div class="researchbox"><rss>http://www.ncbi.nlm.nih.gov/entrez/eutils/erss.cgi?rss_guid=1n3mGKHZyalxjwOlrn2m-Otawl50KeDcGQhVMQyXENkfzXPER5|charset=UTF-8|short|max=10</rss></div>  
<div class="researchbox"><rss>http://www.ncbi.nlm.nih.gov/entrez/eutils/erss.cgi?rss_guid=1n3mGKHZyalxjwOlrn2m-Otawl50KeDcGQhVMQyXENkfzXPER5|charset=UTF-8|short|max=10</rss></div>
== References<br>  ==
 
== References ==


<references />  
<references /> <br>


[[Category:Vrije_Universiteit_Brussel_Project]] [[Category:Electrophysical]] [[Category:PROSTHETIC_AND_ORTHOTICS]]
[[Category:Cervical Spine]] [[Category:Prosthetics and Orthotics]]
[[Category:Vrije_Universiteit_Brussel_Project]]

Revision as of 17:45, 31 May 2017

Description[edit | edit source]

Good-alignment-of-neck.png

Cervical / Neck collars are commonly used by patients who had a surgical intervention of the cervical spine to immobilize the neck. It is also used for the treatment against neck pain, which can be caused by an acute trauma or chronic neck pain. For example after a whiplash injury, the neck collar will be used for both immobilization and to reduce pain. Although the value of the collar over early active mobilizations is being questioned, early mobilizations should give a greater improvement in cervical range of motion and in the reduce of pain after a whiplash injury.[1]

The main goal of neck collars is to prevent or minimise motion in the cervical spine. It also keeps the head in a comfortable gravity-aligned position, this means a normal cervical lordosis. The head is held high on the shoulders and the ears are directly over each shoulder (see figure).


'Note: Even though the term "Cervical Collar" has widely been used, the standarised and universally accepted term will be Cervical Orthosis. The name should be given depending on the parts of the body the orthotic device supporting. For example Cervical Orthosis, Head Cervical Orthosis, Cervico-Thoracic Orthosis , etc.

Types[edit | edit source]

Based on the materials and the hardness of the material the cervical collars can be classified into...

  1. Soft collar
  2. Rigid collar

Soft collar[edit | edit source]

Soft collar.jpg

Soft collars are made out of felt. They are cut to mould around the neck and jaw of the patient, the size should be adjusted to the patient. These collars don’t completely immobilize the neck, they restrict motion and mostly remind the patient of excessive motions (Kinesthetic Reminder). Since the collar is under the chin and supports the chin, it minimizes muscle contraction needed against the gravity forces to keep the head in a normal position .This type of collar does not truly immobilize the neck[2][3][4], it only limits flexion and extension in the end phase. These collars tightly encircle the neck and the felt has little breathing possibilities, so it’s possible that the patient sweats underneath the collar.

                                                               

Rigid collar[edit | edit source]

Rigid collar 1.jpg

The rigid collars are similar to the soft collars but they are made out of plexiglass. They are easily applied and are easy to keep clean, an advantage of the plastic collar. This type of collar also has different sizes which has to fit the patient. These collars restrict a certain motion (not strictly) in flexion and extension.[5] They support the chin but also the occiput, this reduces the extension possibilities, especially in the end phase. A drawback of the rigid collars is that they potentially cause venous outflow obstruction, which might elevate intracranial pressure.[6][7] If there is a clear evidence of an increased intracranial pressure, the collar should be removed or repositioned.[8]

The most frequently prescribed are the Aspen, Malibu, Miami J, and Philadelphia collars. All these can be used with additional chest and head extension pieces to increase stability.

Cervical collars are incorporated into rigid braces that constrain the head and chest together. Examples include the Sterno-Occipital Mandibular Immobilization Device (SOMI), Lerman Minerva and Yale types.[9]

Effective Usage Duration[edit | edit source]

In general the collar should be worn constantly for one week. After that the use of the collar should be gradually decreased. If the collar is worn for a longer period, it could have several effects such as: soft tissue contracture, muscular atrophy, loss of proprioception and coordination but also psychological dependence.[10] This means that the patient will have the feeling that he needs the collar for a safe feeling even though it isn’t necessary.

Several studies are doubtful about the efficiency of the neck collar compared to early mobilizations. They both reduce the pain but the early mobilizations show a greater improvement in cervical range of motion.[1][11] Another study shows no differences between the two interventions.[12]

It has to be said that the collars do not strictly immobilize the neck, they mostly control pain when used for limited periods of time. A use for longer than two weeks should be discouraged because of the side effects (atrophy and shortening of the neck musculature, soft tissue contractions, thickening of subscapular tissues). The most important effect is the increased dependence of the patient and the enhancement of feelings of disability. This will lead to a longer use of the collar by the patient and will strengthen all the disadvantages.

Comparison[edit | edit source]

When different types of cervical collar are compared with respect to mechanical stability (both actively and passively), all collars restrict motion to some extent. The collars ranked from least restrictive to most restrictive: soft collar, Philadelphia collar, SOMI.[5][13] Although, it has to be said that the differences were not usually large. In general the collars do not provide a high level of mechanical restriction of motion and is variably between people.[5]

The soft and rigid collar show no significant differences in movement for the most daily activities. This is because the ADL require only a small percentage of the total range of motion.[14] Both collars can be used for people who are in less pain but need the collar to immobilize the neck and for a sense of security. In this case, the collars act primarily as proprioceptive guides to regulate the movement of the cervical spine rather than as a restraint to physically impede motion.[14]

Treatment cervical radiculopathy: evidence studies showing effectiveness of the cervical collar[edit | edit source]

Cervical collar and rest or physiotherapy and home exercises were compared with wait and see policy for patients with cervical radiculopathy over a period of 6 weeks.

The cervical collar was semi-hard, comfortable and in six different sizes. Patients had to wear it during the first 3 weeks the whole day while also taking as much rest as possible. During the 3 last weeks, they had to decrease the time of wearing a collar a day. After 6 weeks they had to stop wearing it. Physiotherapy included exercises for mobilization and stabilization of cervical spine, and reinforcing superficial and deep neck muscles. Patients had also exercises to do at home. For the wait and see policy patients were asked to continue daily activities as much as possible.

Results show that arm and neck pain were significantly reduced with the collar and physiotherapy in comparison to the wait and see policy. The results for the neck disability index show a significantly improvement for the collar, while the physiotherapy showed the same pattern but wasn’t significant compared to the wait and see policy.

Better results for cervical collar and physiotherapy can be explained thus: cervical collar decreases the (foraminal) compression and inflammation of the nerve root by immobilization, this causes a reduced arm and neck pain. On the other hand, physiotherapy wants to regain the range of motion and strength of the neck musculature so that musculoskeletal problems are avoided. The pain reduction is still unclear.
We can conclude that a semi-hard cervical collar and rest, or physiotherapy and home exercises are effective for short term (6 weeks) reduction of pain for patients with cervical radiculopathy in comparison with wait and see policy.

This has been studied over a period of 6 weeks. 205 patients (aged between 18-75) were randomly divided into 3 groups: a group with a semi-hard collar and rest, a group with physiotherapy and home exercises and a control group. Patients had to show the symptoms of cervical radiculopathy since less than one month, arm pain on VAS of 40mm or more, radiation of arm pain distal to elbow, at least one of provocation arm pain by neck movements, sensory changes in dermatomes, diminished deep tendon reflexes, muscle weakness in myotome. The results were taken at entry, after 3 and 6 weeks follow-up and after 6 month follow-up. Primary outcome measures were VAS for neck and arm pain and the neck disability index.[15]

Clinical Bottom Line[edit | edit source]

The take home message is even though the cervical orthoses are effective for short term pain relief, this cannot used as an alternative to Physiotherapy program. However, if used and weaned appropriately, the cervical orthoses can be an effective adjunct to the patient's treatment program.

Recent Related Research (from Pubmed)[edit | edit source]

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References[edit | edit source]

  1. 1.0 1.1 Mealy K. et al. Early mobilizations of acute whiplash injury. British Medical Journal. 1986; volume 292: 656-666. (LEVEL 1B)
  2. Colachis SC et al. Cervical spine motion in normal women: radiographic study of effect of cervical collars. Archives of physical medicine and rehabilitation. 1973; 58(7): 865-871. (LEVEL 1B)
  3. Fisher SV et al. Cervical orthoses effect on cervical spine motion: roentgenographic and goniometric method of study. Archives of physical medicine and rehabilitation. 1977; 58(3): 109-115. (LEVEL 2B)
  4. Johnson RM et al. Cervical orthoses. A study comparing their effectiveness in restricting cervical motion in normal subjects. Journal of Bone and Joint Surgery. 1977; 59(3): 1185-1188. (LEVEL 2B)
  5. 5.0 5.1 5.2 Sandler AJ. The effectiveness of various cervical orthoses: an in vivo comparison of the mechanical stability provided by several widely used models. Spine. 1996; 21(14): 1624-1629. (LEVEL 1B)
  6. Davies G et al. The effect of a rigid collar on intracranial pressure. Injury. 1996; 27(9): 647-649. (LEVEL 2B)
  7. Mobbs RJ et al. Effect of cervical hard collar on intracranial pressure after head injury. ANZ Journal of surgery. 2002; 72: 389-391. (LEVEL 2B)
  8. Ho A MH. et al. Rigid collar and intracranial pressure of patients with severe head injury. Journal of Trauma. 2002; 53: 1185-1188. (LEVEL 2B)
  9. Shantanu S Kulkarni, DO and Robert H Meier III, "Spinal Orthotics", Medscape Reference
  10. Lieberman JS: Cervical soft tissue injuries and cervical disc disease. In Principles of Physical Medicine and Rehabilitation in the Musculoskeletal Diseases, Grune, New York, 1986: 263-286.
  11. McKinney. Early mobilization and outcome in acute sprains of the neck. British Medical Journal. 1989; 299: 1006-1008. (LEVEL 1B)
  12. Pennie and Agambar. Whiplash injuries. A trial of early management. Journal of Bone and Joint Surgery. 1990; 72B: 277-279. (LEVEL 2B)
  13. Gavin TM et al. Biomechanical analysis of cervical orthoses in flexion and extension: a comparison of cervical collars and cervical thoracic orthoses. Journal of rehabilitation research and development. 2003; 40(6): 527-537. (LEVEL 2B)
  14. 14.0 14.1 Miller, C et al. Soft and rigid collars provide similar restriction in cervical range of motion during fifteen activities of daily living. Spine, volume 35, number 13, 2010. p 1271-1278. (LEVEL 1B)
  15. Kuijper B et al. Cervical collar or physiotherapy versus wait and see policy for recent onset cervical radiculopathy : randomised trial. BMJ. 2009;1-7. (LEVEL B)