Neck pain can be caused by a variety of conditions.

The general underlying causes can be separated into the following categories:

• Nerve compression
• Muscle strain
• Joint issues
• Traumatic injury (Torlincasi & Waseem, 2022)
• Disease

Nerve compression is caused when the nerves in the neck are damaged by inflammation, shifted/abnormal tissues, and/or disease.

Here are some causes of neck pain caused by nerve compression:

Bad posture: Extended time looking down or with a rounded shoulder can change the length of muscles in the neck. These changes can shift the location of cervical bones, muscles, and other tissues, causing them to press on a nerve.
Bone spurs: Abnormal bone tissue from the spine can compress the nerves around it.
Herniated cervical discs
Cervical radiculopathy/Pinched nerve syndrome
Cervical spinal stenosis: The narrowing of the spinal space at the neck.
Cancer(s) found in the neck

Joint issues can be caused by:

• Arthritis/Osteoarthritis
• Hypermobility
• Spinal spondylosis: The natural degeneration of joints due to old age.

Causes of neck pain due to traumatic injuries include:

• Whiplash
• Car accidents
• Sport injuries, especially if they are repeated injuries
• Falls
• Traumatic injuries

There are many diseases/disorders that can cause or contribute to neck pain. Among these are:

• Arthritis/Osteoarthritis
• Cervical dystonia
• Myofascial pain syndrome
• Chronic migraine
• Amyotrophic lateral sclerosis (ALS)
• Anxiety

The main cause of neck pain caused by muscle strain is bad posture. Strained muscles can be quite painful and reduce mobility until they are allowed to heal, which may involve some stretching depending on the muscles involved.

The main symptom of neck pain is pain. However, it can be accompanied by other symptoms, such as:

• Numbness
• Muscle weakness
• Shooting pain
• Soreness

Botulinum toxin injections (BTI), also known as Botox, is a treatment that relaxes muscles and reduces pain-related neurochemical signals by injecting a mild neurotoxin into an area (Padda & Tadi, 2023).

The injections contain a purified and safe strain of Clostridium botulinum, the bacteria responsible for botulism food poisoning, along with an analgesic. The bacterial toxins act on the muscle receptors and prevent the neurotransmitter acetylcholine from binding to the nerve receptors.

As acetylcholine is responsible for initiating muscle contraction, blocking its effect on the muscle causes mild muscle paralysis. Furthermore, acetylcholine helps transmit pain signals through the nerves. By blocking its receptors, BTI reduces the ability of acetylcholine to relay pain to the brain.

BTI is the introduction of a safe and purified strain of Clostridium botulinum, the bacteria responsible for botulism food poisoning, into the body through an, or a series of, injection(s). This bacteria creates a substance that acts on the muscle receptors and prevents the neurotransmitter acetylcholine from binding to its receptors.

By blocking the acetylcholine from attaching to its muscle receptors, it prevents those muscles from contracting, forcing them into a state of paralysis. This allows strained muscles to rest and recover from any injuries that may be causing pain.

Furthermore, by blocking acetylcholine from attaching to its nerve receptors, the nerve’s ability to transmit pain signals to the brain is interrupted. This leads to less overall pain as the brain does not receive those signals.

This type of treatment can take up to 14 days to show any results. On average, it lasts between 60 to 90 days, though this may depend on the individual and the disorder being treated.

BTI for neck pain should be considered when more conventional methods of pain management do not provide sufficient pain relief (The International Centre for Allied Health Evidence, 2017). However, it is only effective in cases where the underlying cause of the neck pain involves either muscles or nerves. Furthermore, the current research does not support its use for chronic generalized neck pain (Awan, 2017).

BTI should be considered for the treatment of:

• Cervical Dystonia (Jankovic et al., 2023)
• Migraines (Onan et al., 2022)

Current research does not support its use to treat:

• Myofascial pain syndrome (Soares et al., 2014)
• Neck injuries
• Arthritis/Osteoarthritis
• Chronic neck pain (Awan, 2017)
• Whiplash
• Joint disorders/issues

Like all medical treatments, BTI carries some risk of side effects (Morra et al., 2016).

The following side effects are benign and should disappear within a few days after the treatment:

• Fatigue
• Mild headaches
• Flu-like symptoms
• Nausea/vomiting
• Discomfort/bleeding/bruising at the injection site

The following side effects can take up to 2 weeks to disappear:

• Drooping eyelids
• Excessive salivation
• Mild facial paralysis
• Dry eyes
• Infection at the injection site

Some side effects may need additional medical care. Please contact your medical team if you have any concerns.

These rarer side effects are more severe and require immediate medical attention:

• Difficulties breathing/swallowing/speaking
• Sudden generalized muscle weakness
• Sudden visual distortions/change
• Sudden bladder control issues

If you experience any of the above side effects after a treatment, please contact 911 or have someone bring you to the nearest medical emergency center.

Some individuals should not receive BTI. These include:

1. Individuals planning a pregnancy or who are pregnant
2. Breastfeeding individuals
3. Individuals with a neuromuscular disorder such as Amyotrophic Lateral Sclerosis (ALS) or Myasthenia Gravis
4. Presence of a previous allergic reaction to BTI or injections

Wilderman Medical Clinic offers BTI as part of its pain management clinic.

Please note that OHIP covers BTI injections only in certain situations. Certain private insurance companies may cover the injections under their guidelines.

Awan, K. H. (2017). The therapeutic usage of botulinum toxin (Botox) in non-cosmetic head and neck conditions – An evidence based review. Saudi Pharmaceutical Journal, 25(1), 18–24. https://doi.org/10.1016/j.jsps.2016.04.024

Jankovic, J., Tsui, J., & Brin, M. F. (2023). Treatment of cervical dystonia with Botox (onabotulinumtoxinA): Development, insights, and impact. Medicine, 102(S1), e32403. https://doi.org/10.1097/md.0000000000032403

Onan, D., Bentivegna, E., & Martelletti, P. (2022). OnabotulinumtoxinA treatment in Chronic migraine: Investigation of its effects on disability, headache and neck pain intensity. Toxins, 15(1), 29. https://doi.org/10.3390/toxins15010029

Padda, I. S., & Tadi, P. (2023, November 6). Botulinum toxin. StatPearls – NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK557387/

Soares, A., Andriolo, R. B., Atallah, Á. N., & Da Silva, E. M. (2014). Botulinum toxin for myofascial pain syndromes in adults. The Cochrane Library, 2021(6). https://doi.org/10.1002/14651858.cd007533.pub3

The International Centre for Allied Health Evidence. (2017). Systematic Review of Literature: The Effectiveness of Botulinum Toxin Injection for Neck Pain as a Form of Interventional Pain Management: Technical report. In The Accident Compensation Corporation. https://www.acc.co.nz/assets/research/06d93d26ea/Botox-injections-for-neck-pain-systematic-review.pdf

Torlincasi, A. M., & Waseem, M. (2022, August 22). Cervical injury. StatPearls – NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK448146/