Possible associations
TMD has been suggested to be associated with other conditions or factors, with varying degrees of evidence and some more commonly than others. E.g. It has been shown that 75% of people with TMD could also be diagnosed with fibromyalgia, since they met the diagnostic criteria, and that conversely, 18% of people with fibromyalgia met diagnostic criteria for TMD. A possible link between many of these chronic pain conditions has been hypothesized to be due to shared pathophysiological mechanisms, and they have been collectively termed "central sensitivity syndromes", although other apparent associations cannot be explained in this manner. Recently a plethora of research has substantiated a causal relationship between TMD and Obstructive Sleep Apnea (OSA). Severe TMD restricts oral airway opening, and can result in a retrognathic posture that results in glossal blockage of the oropharynx as the tongue relaxes in sleep. This mechanism is exacerbated by alcohol consumption, as well as other chemicals that result in reduced myotonic status of the oropharynx. Obstructive sleep apnea. Headache. Chronic neck pain. Chronic back pain. Systemic joint laxity. Rheumatoid arthritis. Irritable bowel syndrome. Interstitial cystitis. Regular scuba diving. Pathophysiology
Anatomy and physiology
Temporomandibular joints
The temporomandibular joints are the dual articulation of the mandible with the skull. Each TMJ is classed as a "ginglymoarthrodial" joint since it is both a ginglymus (hinging joint) and an arthrodial (sliding) joint, and involves the condylar process of the mandible below, and the articular fossa (or glenoid fossa) of the temporal bone above.
in several papers the involvement of the cranial nerve nuclei and central gray matter on MRI, is very specific to WE in the appropriate clinical setting. Non-recovery upon supplementation with thiamine is inconclusive.The sensitivity of MR was 53% and the specificity was 93%. The reversible cytotoxic edema was considered the most characteristic lesion of WE. The location of the lesions were more frequently atypical among people who drank appropriate amounts of alcohol, while typical contrast enhancement in the thalamus and the mammillary bodies was observed frequently associated with alcohol misuse. These abnormalities may include:
Dorsomedial thalami, periaqueductal gray matter, mamillary bodies, tectal plate and brainstem nuclei are commonly affected. Involvement is always bilateral and symmetric. Value of DWI in the diagnosis of WE is minimal. Axial FLAIR MRI images represent the best diagnostic MRI sequence. Contrast material may highlight involvement of the mamillary bodies.There appears to be very little value for CT scans.Thiamine can be measured using an erythrocyte transketolase activity assay, or by activation by measurement of in vitro thiamine diphosphate levels. Normal thiamine levels do not necessarily rule out the presence of WE, as this may be a patient with difficulties in intracellular transport. Prevention
There are hospital protocols for prevention, supplementing with thiamine in the presence of: history of alcohol misuse or related seizures, requirement for IV glucose, signs of malnutrition, poor diet, recent diarrhea or vomiting, peripheral neuropathy, intercurrent illness, delirium tremens or treatment for DTs, and others.