Headaches
Headaches have multiple causes, the two most common of which are tension headaches and migraine. In the French language, we tend to use " migraine " for " headache ", which adds confusion.
Very often the causes of headaches overlap and we should not have an overly dogmatic view of it. For example, C5-C6 osteoarthritis can lead to overcompensation in C4-C5 causing muscle contracture with tension headaches. This contracture can lead to Arnold's neuralgia or act as a trigger for a real migraine ... Not so simple ...
Causes of headache
Differential diagnosis of headache:

 

 
Arnold's neuralgia
Arnold's nerve:

 

Both the small occipital nerve and the large occipital nerve (Arnold's nerve) can cause fairly typical headaches (unilateral, turning above the ear).

These two nerves can be tested through a local block with an anesthetic such as chirocaine. If the block is done correctly, it results in transient anesthesia of the corresponding area of ​​the scalp. The test block does not differentiate primary Arnold's neuralgia from secondary Arnold's neuralgia and may therefore lead to unnecessary operations.

Céphalées: nef d'Arnold - Schéma anatomique
Differential diagnosis of Arnold's neuralgia:

 

  • Small occipital nerve

  • Large occipital nerve

  • Combination of small and large occipital nerves

  • Arnold's primary neuralgia

Arnold's primary neuralgia is a controversial entity that is believed to be due to thickening of the fascia as the nerve emerges. This is an analogy with carpal tunnel syndrome for the median nerve. The occipital artery could play a role in this compression at the emergence of the large occipital nerve. Several works have cast doubt on this hypothesis and it is likely that Arnold's primary neuralgia entity exists, but is much less common than what is believed.

  • Arnold's secondary neuralgia

Arnold's secondary neuralgia is caused by muscle contracture in the neck that narrows the opening of the nerve by pulling on the fascia. This is the most common cause, usually related to a common cervical pathology such as facet osteoarthritis.

Treatment of Primary Arnold's Neuralgia:

 

  • Local infiltration of steroids as the nerve emerges (avoiding injecting the nerve itself, which could lead to painful dysesthesia)

  • Thermocoagulation of the nerve (causing on the other hand anesthesia of part of the scalp and a risk of painful anesthesia by deafferentation)

  • Neurolysis of the nerve by partial section of the fascia (as for a carpal tunnel)

Treatment of secondary Arnold's neuralgia:

 

  • Treat the origin of the muscle contracture :

    • Most often, the origin is cervical pathology:

      • With root irritation (arthritis, hernia)

      • With a facet syndrome (overcompensation, static disorders, facet arthritis, ...)

      • With ligament damage (static, postoperative disorders, etc.)

    • Primary muscle damage. An increasingly common cause is the use of statins to lower patients' cholesterol

  • Relax the musculature

    • Hot, massages, chiropractic, osteopathy, ... are all very effective, but unfortunately with a very limited duration of effectiveness (often a few days)

    • Botulinum toxin

    • Electrical stimulation by implanted electrodes (controversial)

  • Limit the impact to the emergence of the nerve

    • Local infiltration of steroids as the nerve emerges (avoiding injecting the nerve itself, which could lead to painful dysesthesia)

    • Thermocoagulation of the nerve (causing on the other hand anesthesia of part of the scalp and a risk of painful anesthesia by deafferentation)

    • Neurolysis of the nerve by partial section of the fascia (as for a carpal tunnel)

 
Intracranial hypertension
Hypertension intracrânienne: Clinique
Intracranial hypertension is a very rare cause of headache. Due to the potential severity of the underlying causes and the need to initiate treatment quickly, however, without a bad pun, always keep it in mind.
The typical anamnesis as described below is only very rarely present and it is the atypical forms that predominate. Formally, it is never possible to exclude intracranial hypertension (particularly at an early stage) on the sole description of the headache. More critical is the absence of associated elements suggesting focal signs. Neuroradiological investigations will often be waived if the picture is very suggestive of another pathology, but then accepting the tiny probability of missing an underlying lesion.

Typical history:

 

It should be borne in mind that this typical anamnesis is only rarely found.

If one or more elements are present, it is wise to organize as soon as possible a neurosurgical consultation and / or a brain MRI (with and without contrast)

Differential diagnosis of intracranial hypertension: