Chronic Headache
Headache is a common problem. Fortunately a significant proportion of headaches can be managed by commonly used painkillers. In certain types of headaches prophylactic agents are used to reduce the frequency of attacks. However, there still remains a subgroup of patients with difficult to manage headaches despite all measures. For this subgroup pain clinic offers interventions and multi-disciplinary input, over and above the traditional approach of using painkillers. Multi-disciplinary approach helps in addressing concomitant magnifiers/ triggers such as anxiety, depression, altered sleep cycle, medication overuse, life style and poor posture.
In clinical practice, an overwhelming majority of headaches are either a tension-type headache, migraine, cluster headache or medication overused headache. Extra cranial sources of headaches such as nerves, joints and muscles can be easily missed. The term Cervicogenic Headaches is used for headaches originating from cervical spine pathology or surrounding soft tissues. Examples include neck facet or Atlantoaxial joint pathology, headaches secondary to third occipital nerve, supraorbital neuralgia, and occipital neuralgia, sternocleidomastoid and trapezius muscle spasms. These types of headaches may be accompanied by neck pain, stiffness and are commonly undertreated.
Some of the interventions available via the pain clinic include
Facet Joint Injections & Radiofrequency ablation
Headaches originating from facet joints are more commonly observed in the elderly and after whiplash injury (flexion/extension injuries). Clinical diagnosis is often difficult as the features overlap with other types of headaches. Diagnostic injections can help identify the pain generators in such cases. Pain originating from these joints can be felt in the base of the skull, neck, upper back, mid-back and shoulders. Please follow the link to Facet joint injections to find out more on this treatment.
Third Occipital Nerve Block and Radiofrequency
The third occipital nerve originates from the cervical spine and supplies sensation to a joint in the neck (C2-3 zygapophyseal joint) and a small area at the back of head. This nerve or the joint it supplies can be a source of headaches localised to the back of head on one side. Sometimes the headache can spread towards the top of the head. This occurs more commonly after whiplash injury.
A diagnostic block involving injection of local anaesthetic close to the nerve can help determine if this nerve is the source of your headache. This is performed under x ray guidance. If the diagnostic test is positive then radiofrequency ablation of the nerve can provide long lasting relief.
Occipital Nerve Block and Radiofrequency
Greater Occipital Nerve (GON) block is frequently utilized in management of different types of headache and for establishing the diagnosis of occipital neuralgia. This nerve is located at the back of head and pain originating from this presents as shooting, stabbing pain with altered sensation in the area supplied by the nerve. Sometimes the area can be unusually sensitive.
Nerve block can be performed distally using landmarks or proximally using ultrasound. This nerve travels through various fascial planes and has the potential of getting entrapped anywhere along the path. I prefer to use the proximal approach as this targets the nerve soon after it originates from the spinal nerves before it gets entrapped anywhere along its course. Local anaesthetic block can help in confirming the diagnosis and radiofrequency treatment can help provide long pasting pain relief.
Sphenopalatine Ganglion Block
Sphenopalatine ganglion is a collection of nerve cells located behind the nose which serves as a relay centre for messages being transmitted to the brain. This is closely linked to one of the main nerves involved in headaches, facial pain (trigeminal nerve) and with many other nerves such as those involved in regulation of tear glands.
Sphenopalatine ganglion block is used for conditions such as cluster headaches, migraine, atypical facial pain and cancer of head and neck. A block with local anaesthetics temporarily interrupts the transmission of nerve impulses producing pain relief. It can be performed by inserting local anaesthetic soaked cotton swabs through the nose with the head tilted backward. Alternatively, it can be performed using x-ray guidance from the side of the face. The duration of pain relief is variable.
Botox for Migraine
Botox is well known for its cosmetic usage. When injected into muscles it partially blocks the nerve impulses and reduces the muscle contractions. In chronic migraine this can help by reducing the frequency of headaches and the effects can last for 8 - 12 weeks.
Botox is not the first line treatment for migraine and is used in adult patients with chronic migraine who have unsuccessfully tried at least three other medications to prevent migraine. Diagnosis of chronic migraine is made when patients have 15 or more headache days in a month of which at least eight are migraine headaches.
Other Nerve Blocks & Pulsed Radiofrequency
Blocks and radiofrequency treatment of nerves e.g. supraorbital, supratrochlear nerve are used when the pain is localised to the distribution of a specific nerve.
Trigger Point Injection
Muscles ability to contract and relax plays an important role in body functioning. When muscles fail to relax, they form knots or tight bands known as trigger points. In simple words trigger points are irritable areas/ bands of tightness in a muscle. Pressure over a trigger point produces local soreness and may refer pain to other body parts. Common causes include inflammation, injury of the muscle or the neighbouring structures. Poor posture and repetitive strain are other predisposing factors. Trigger points can limit the range of movement; affect posture predisposing other areas to unaccustomed strain.
Trigger points are commonly found in head, neck, and shoulder muscles. They can be the source of localised pain, headaches and may also play a role in magnifying headaches due to other causes e.g. migraine, tension headache.
Trigger point injections are performed in an outpatient/ day-care setting and involve injection of local anaesthetic with or without a small dose of steroid into the painful muscle. The local anaesthetic blocks the pain sensations and the steroids help in reducing the inflammation, swelling. I prefer to perform these injections under ultrasound guidance as it improves the accuracy and reduces the chances of complications. Post injection physiotherapy is essential to prevent recurrence and maximise the benefits.
These interventions are used in combination with physiotherapy, psychology, medication optimisation and complimentary therapies (such as acupuncture, TENS, meditation, ayurveda and wellness).
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