Understanding Stroke: The Jaw-Dropping Side Effect Explained

A stroke can damage the nerves that control the muscles in the face, causing the jaw to drop and lock. This condition, known as lockjaw or trismus, affects the way a person opens and closes their mouth, making it difficult to eat, drink, or even talk. It is characterized by the inability to open the mouth wide, and it may even be completely closed with the teeth tightly clenched together. Lockjaw is not a condition itself but a symptom, and the underlying cause can vary. In the case of a stroke, the damage to the nerves can result in the jaw dropping and locking.

The jaw may drop and lock after a stroke, due to nerve damage

A stroke can cause the jaw to drop and lock due to nerve damage. This is often one of the first signs of a stroke and can be identified using the F.A.S.T system, which includes checking for face drooping. A stroke is the No. 1 cause of disability in the U.S., and recognising a stroke early can save you or your loved one from paralysis.

The jaw may drop and lock after a stroke due to damage to the nerves that control the muscles in the face. This condition is known as lock jaw or trismus, and it can be painful and make it difficult to open the mouth, eat, speak, or even breathe. The symptoms of lock jaw can range from mild to severe.

Lock jaw is a symptom, not a condition in itself, and there are various underlying causes. It can be caused by jaw injury or damage, teeth grinding, TMJ disorders, or other medical conditions. TMJ stands for the temporomandibular joint, which connects the lower jaw to the skull and is located just in front of the ear.

Treatments for lock jaw depend on the underlying cause and may include wearing a splint or bite plate to realign the jaw, medication, physical therapy, or surgery. Botox can also be used to relax the muscles in the jaw, but it is not a cure.

This is a symptom of oromandibular dystonia (OMD)

Oromandibular dystonia (OMD) is a rare focal neurological disorder that affects the mouth, face, and jaws. It is characterised by forceful muscle contractions of the face, jaw, and/or tongue. These muscle contractions cause involuntary movements that interfere with opening and closing the mouth and may affect chewing and speech. OMD is sometimes referred to as cranial dystonia, which is a broader description for dystonia that affects any area of the face and mouth.

OMD is a symptom of various conditions, including:

• Peripheral trauma, such as dental procedures or facial injuries
• Drug exposure
• Wilson's disease
• Central nervous system (CNS) trauma
• Neuroleptic exposure
• Hypoxic brain damage
• Metabolic disorders
• Ischemic or demyelinating lesions in the upper brain stem

OMD can be inherited or idiopathic, or it can be acquired from secondary causes such as those listed above. The onset of symptoms usually occurs between the ages of 40 and 70 and is more common in women.

The diagnosis of OMD is complicated as it presents in various forms and severities, and there is no specific diagnostic medical test. Treatment for OMD is highly individualised and may include oral medications, botulinum neurotoxin injections, muscle afferent block, deep brain stimulation surgery, and speech and swallowing therapy.

OMD is caused by involuntary contractions of the jaw, tongue and perioral muscles

Oromandibular dystonia (OMD) is a movement disorder characterised by involuntary, paroxysmal, and patterned muscle contractions of varying severity. These contractions result in sustained spasms of the masticatory muscles, affecting the jaws, tongue, face, and pharynx. OMD is considered a focal dystonia involving the mouth, jaw, and tongue, and is manifested by involuntary muscle contractions that produce repetitive, patterned movements of the involved structures.

OMD is caused by involuntary contractions of the jaw, tongue, and perioral muscles, which can be either idiopathic (primary) or secondary to a peripheral injury. Head and neck dystonia manifest clinically by the presence of involuntary sustained, forceful muscle contractions, and characteristic rhythmic movements and abnormal posture. Craniocervical manifestations of dystonia affect the person's quality of life by interfering with the ability to speak and swallow and in social interaction.

Dystonia is a broad spectrum, from a contraction of a single muscle group to a disabling dysfunction of multiple groups. Dystonia is commonly initiated by voluntary motion but may later become sustained and extend to other body regions. Stress or fatigue often worsen dystonia, while relaxation or sensory stimulation can reduce it.

OMD can be clinically divided into jaw-opening (JO), jaw-closing (JC), mixed (two or more combinations of JO, JC, or jaw deviation), lingual, and orobuccolingual subtypes. Although OMD is a focal dystonia, it may also be a part of segmental or generalized dystonia. The most common type of OMD is jaw-opening dystonia, followed by lingual dystonia, jaw-closing dystonia, and mixed dystonia.

OMD can be treated with Botox injections to relax the jaw muscles

Oromandibular dystonia (OMD) is a movement disorder that consists of involuntary spasms of the jaw, mouth, and tongue muscles, resulting in jaw closure, trismus (jaw clenching), and bruxism (tooth grinding). This condition often leads to secondary dental wear and temporomandibular dysfunction. While the cause of OMD remains unknown in most cases, it has been associated with drug-induced, post-anoxic, neurodegenerative disorder-related, and head injury-related factors.

One effective treatment for OMD is Botox injections, which can significantly improve patients' quality of life. Botox, or botulinum toxin type A, works by blocking the release of acetylcholine at the neuromuscular junction, leading to temporary paralysis of the targeted muscles. This reduction in muscle activity can alleviate pain and decrease hyperactivity in muscles involved in OMD.

The benefits of Botox injections for OMD include:

• Long-lasting relief, with injections needed only every 3-6 months.
• Improvement in muscle hyperactivity, reducing involuntary muscle contractions.
• Enhanced quality of life for patients, providing relief from painful symptoms.
• A safe and effective treatment option, backed by scientific evidence.

However, it is important to note that Botox therapy for OMD may result in potential side effects, such as bruising, muscle weakness, and unintended spread of the toxin, which can lead to unwanted muscle paralysis. Therefore, it is crucial to consult a licensed healthcare provider to determine if Botox injections are suitable for treating OMD.

Other treatments include medication, physical therapy and surgery

A stroke can cause oromandibular dystonia (OMD), a cranial segmental dystonia of the lips, jaw, and tongue. This can lead to involuntary mouth closure or opening, deviation of the jaw, tongue movements, or any combination of these due to repetitive or sustained spasms of masticatory, facial, or lingual muscles.

There are several treatment options for OMD, including medication, physical therapy, and surgery.

Medication

Medications can be used to treat the underlying cause of the stroke, such as high blood pressure or heart problems, and to prevent a second stroke. Common medications prescribed after a stroke include:

• Blood pressure drugs, such as diuretics, ACE inhibitors, beta-blockers, calcium channel blockers, and angiotensin II receptor blockers.
• Anticoagulants, such as warfarin and heparin, to prevent blood clots.
• Antiplatelets, such as aspirin, to prevent clots from forming.
• Heart rate and rhythm drugs, such as beta-blockers, calcium channel blockers, and digoxin, to control the heart rate and rhythm.
• Statins to lower cholesterol and the risk of a second stroke.
• Medications to control blood sugar levels if the patient has type 2 diabetes or prediabetes.
• Antidepressants, such as selective serotonin reuptake inhibitors (SSRIs), to treat depression and anxiety, which are common after a stroke.
• Muscle relaxants, such as cyclobenzaprine and carisoprodol, to relieve muscle spasms and cramping.
• Anticonvulsants, such as gabapentin and pregabalin, to treat neuropathic pain.
• Botulinum toxin (Botox) injections to treat muscle spasms and pain.

Physical Therapy

Physical therapy can be an important part of stroke recovery, helping to improve movement, balance, and coordination. Specific exercises and therapies can be prescribed to treat OMD, such as:

• Oral sensory feedback, such as holding a toothpick in the mouth, to diminish dystonic movements.
• Speech therapy to improve speech and chewing, which can be more difficult with OMD.
• Range-of-motion exercises to improve jaw movement and flexibility.
• Strengthening exercises to improve muscle strength and control in the jaw and face.
• Stretching exercises to improve flexibility and reduce muscle spasms.
• Massage therapy to reduce muscle tension and pain.

Surgery

In some cases, surgery may be recommended to treat OMD. Surgical options may include:

• Orthognathic surgery to correct jaw alignment and improve function.
• Jaw joint replacement surgery to replace the damaged or diseased jaw joint with an artificial one.
• Nerve decompression surgery to relieve pressure on the affected nerve and improve function.
• Deep brain stimulation (DBS) to deliver electrical stimulation to specific areas of the brain, which can help reduce abnormal movements and improve muscle control.

Frequently asked questions