Pterygoid Myofascial Pain Syndrome (MPS)

Overview

Pterygoid Myofascial Pain Syndrome is a type of chronic facial pain that originates from trigger points (hyper‑irritable spots) within the medial or lateral pterygoid muscles—two deep muscles that control jaw opening, closing, and sideways movements. When these muscles develop taut bands or “knots,” they can refer pain to the TMJ (temporomandibular joint), teeth, ear, and even the neck.

• Who it affects: Adults 20–55 years old, with a slight female predominance (≈ 60 % women).
• Prevalence: Myofascial pain disorders account for ~30 % of all temporomandibular disorders (TMD). Among TMD patients, the pterygoid muscles are implicated in 15–25 % of cases.^{[1] Mayo Clinic}
• Impact: Persistent pain can impair chewing, speech, and quality of life; up to 20 % of sufferers report missing work or school days.^{[2] CDC}

Symptoms

Symptoms vary in intensity and may wax or wane. The following list includes the most frequently reported features:

Primary facial pain

• Dull, aching pain deep in the cheek, just in front of the ear.
• Sharp, stabbing pain when the jaw is opened wide, chewed, or moved sideways.
• Referred pain to the upper molars, ear canal, or the side of the head (often mistaken for dental or ear infection).

Trigger‑point signs

• Palpable “knot” or taut band within the pterygoid muscle.
• Local twitch response when the knot is pressed.
• Reproduction of the patient’s typical pain pattern with pressure.

Associated functional symptoms

• Limited jaw opening (< 35 mm) or a feeling of “jaw lock.”
• Clicking or popping of the TMJ.
• Ear fullness, tinnitus, or a sensation of fluid in the ear.
• Headache, especially frontal or temporal.
• Neck and shoulder tension on the same side.

Red‑flag symptoms (suggest an alternate diagnosis)

• Sudden, severe facial swelling or fever.
• Numbness or weakness of the face.
• Persistent loss of hearing.
• Difficulty swallowing or breathing.

Causes and Risk Factors

Underlying mechanisms

Myofascial pain arises when muscle fibers develop sustained contraction, leading to ischemia, accumulation of nociceptive metabolites, and sensitization of nerve endings.

• Overuse or micro‑trauma – frequent gum chewing, clenching, or bruxism.
• Postural strain – forward head posture and prolonged computer use increase tension on the pterygoids.
• Dental factors – malocclusion, missing teeth, or poorly fitting dentures.
• Trauma – whiplash, facial injury, or recent dental procedures.
• Psychologic stress – heightens muscle tone through the sympathetic nervous system.

Risk factors

• Women (especially ages 30‑45) – hormonal influences may affect muscle pain thresholds.
• History of TMD, bruxism, or chronic headaches.
• Occupations with repetitive jaw use (musicians, singers, assembly‑line workers).
• Stressful lifestyle or anxiety disorders.
• Certain systemic conditions: fibromyalgia, rheumatoid arthritis, or chronic fatigue syndrome.

Diagnosis

Because symptoms overlap with dental, ENT, and neurologic disorders, a systematic approach is essential.

Clinical evaluation

• History taking – onset, aggravating/relieving factors, parafunctional habits, and associated headache or ear symptoms.
• Physical examination – palpation of the pterygoid region (intra‑oral or extra‑oral), assessment of jaw range of motion, and evaluation of trigger points.
• Diagnostic criteria – The Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) includes a Myofascial Pain subtype that specifically addresses pterygoid involvement.^{[3] NIH}

Imaging and adjunct tests (used to rule out other conditions)

• Panoramic radiograph or cone‑beam CT – to exclude dental pathology, TMJ osteoarthritis, or aneurysmal bone cyst.
• MRI – best for soft‑tissue assessment; helps differentiate muscle inflammation from joint disc displacement.
• Electromyography (EMG) – occasionally used in research settings to document abnormal muscle activity.

When to refer

If the pain persists despite initial therapy, or if red‑flag symptoms appear, referral to a orofacial pain specialist, oral‑maxillofacial surgeon, or neurologist is recommended.

Treatment Options

Treatment is multimodal, targeting the muscle trigger points, reducing inflammation, and correcting contributing habits.

Conservative, first‑line therapies

• Manual therapy
  • Intra‑oral myofascial release or external massage performed by a physical therapist or dentist trained in TMD.
  • Trigger‑point deactivation (dry needling or ischemic compression).
• Jaw exercises – gentle stretching (e.g., repeat opening/closing, resisted lateral movements) 2–3 times daily to improve mobility.
• Heat/Cold therapy – 15 minutes of warm moist heat or a cold pack before/after exercises.
• Occlusal splint – a stabilization night guard to reduce clenching and protect the muscles.
• Pharmacologic relief
  • Acetaminophen or NSAIDs (ibuprofen 400‑600 mg q6‑8h) for short‑term pain control.
  • Low‑dose tricyclic antidepressants (e.g., amitriptyline 10‑25 mg at night) for chronic pain modulation.
  • Topical NSAIDs or lidocaine patches may provide localized relief.

Procedural interventions (for refractory cases)

• Botulinum toxin type A injections – 2–4 U per injection site into the medial/lateral pterygoid; effect lasts ~3‑4 months.^{[4] Cleveland Clinic}
• Trigger‑point injection – 0.5 mL of 0.5 % lidocaine or a mixture of lidocaine + corticosteroid.
• Ultrasound‑guided radiofrequency ablation – emerging technique for long‑lasting pain reduction.
• Physical‑therapy modalities – low‑level laser therapy, extracorporeal shockwave therapy, or ultrasound.

Addressing contributing factors

• Stress management (cognitive‑behavioral therapy, mindfulness, yoga).
• Dental correction if malocclusion is identified.
• Behavioral habit training – awareness of jaw clenching, use of a “soft‑tongue” technique.
• Ergonomic adjustments – monitor height, head‑tilt reduction, regular breaks from screen time.

Living with Pterygoid Myofascial Pain Syndrome

Daily self‑care checklist

1. Morning routine: 5‑minute warm compress, followed by gentle mouth‑opening stretches (e.g., place a finger on the chin, open slightly, hold 5 seconds, repeat 10×).
2. Throughout the day: Keep a posture reminder; shoulders relaxed, chin tucked slightly. Take a 1‑minute jaw relaxation pause every hour.
3. Evening: Use a night guard if bruxism is present; apply a cold pack for 10 minutes if muscles feel sore.
4. Nutrition: Choose soft foods (yogurt, smoothies) for 2‑3 days after a flare; avoid chewing gum and extremely tough meats.
5. Hydration: Adequate water intake helps maintain muscle elasticity.

When to call your provider

• Pain persists > 3 weeks despite self‑care and OTC meds.
• New ear symptoms (loss of hearing, drainage) or facial numbness.
• Jaw “lock” that prevents opening wider than 20 mm.

Prevention

• Maintain good posture – keep the screen at eye level and avoid forward head tilt.
• Limit parafunctional habits – chew gum < 5 minutes/day; use a “resting tongue” position (tongue on the roof of the mouth).
• Stress reduction – regular aerobic exercise, meditation, or progressive muscle relaxation.
• Regular dental check‑ups – adjust bite issues early.
• Strengthen surrounding muscles – neck and upper‑back strengthening exercises can off‑load the pterygoids.

Complications

If untreated, chronic pterygoid MPS can lead to:

• Persistent TMD with progressive joint degeneration.
• Secondary headaches or migraine‑type pain.
• Psychological distress – anxiety, depression, or sleep disturbance.
• Development of secondary trigger points in adjacent muscles (masseter, temporalis, sternocleidomastoid).
• Altered bite leading to dental wear or temporomandibular joint arthritis.

When to Seek Emergency Care

References

1. Mayo Clinic. “Temporomandibular Joint Disorders (TMD).” 2023. Link.
2. Centers for Disease Control and Prevention. “Chronic Pain in the United States.” 2022. Link.
3. National Institute of Dental and Craniofacial Research. “Diagnostic Criteria for Temporomandibular Disorders (DC/TMD).” 2021. Link.
4. Cleveland Clinic. “Botulinum Toxin for Temporomandibular Joint Disorders.” 2024. Link.