Digastric Trigger Points

Introduction

The digastric muscle is a small but essential muscle in the neck that plays a key role in jaw movement, swallowing, and speech. When trigger points develop in this muscle, they can cause jaw pain, throat discomfort, and ear pain, often mimicking TMJ dysfunction, throat infections, or earaches.

Name and Area

  • Name: Digastric

  • Area: Located under the jawline, spanning from the mastoid process of the temporal bone to the mandible, with two muscle bellies:

    • Posterior Belly: Runs from the mastoid process to the hyoid bone.

    • Anterior Belly: Runs from the hyoid bone to the mandible.

Indications

Digastric trigger points may contribute to:

  • Pain Under the Jaw (Can Mimic TMJ or Dental Pain)

  • Pain That Radiates to the Ear, Resembling an Ear Infection

  • Pain or Tightness When Swallowing (Often Mistaken for a Sore Throat or Throat Inflammation)

  • Clicking or Tightness in the Jaw When Opening or Closing the Mouth

  • Tension or Discomfort at the Base of the Skull (Can Mimic Occipital Neuralgia)

  • Difficulty Maintaining an Open Mouth (E.g., During Dental Visits)

Pain from this muscle is often mistaken for TMJ dysfunction, ear infections, or throat issues.

Muscle Action

  • Jaw Depression: Helps lower the mandible (opening the mouth).

  • Hyoid Bone Elevation: Assists in swallowing and stabilizing the throat.

The digastric works closely with the suprahyoid muscles to support chewing, speaking, and swallowing.

Signs and Symptoms

Individuals with digastric trigger points often report:

  • Pain Under the Chin or Jawline (Worse When Swallowing or Talking)

  • Referred Pain to the Ear (Can Be Mistaken for an Ear Infection or Eustachian Tube Dysfunction)

  • Tension at the Base of the Skull (Occipital Pain That Can Resemble a Headache)

  • Clicking, Tightness, or Mild Locking in the Jaw Joint

  • A Feeling of Throat Tightness or Constriction (Can Mimic Anxiety or Throat Inflammation)

Pain worsens with prolonged talking, chewing, or jaw tension (clenching, grinding, or stress-related tightening of the jaw).

Perpetuating Factors

Common causes of digastric trigger points include:

  • Jaw Clenching or Teeth Grinding (Bruxism, Often During Sleep or Stressful Situations)

  • Frequent Yawning or Mouth Opening (E.g., During Dental Work or Singing)

  • Poor Neck Posture (Forward Head Position Leading to Increased Jaw Tension)

  • Excessive Talking, Singing, or Playing Wind Instruments

  • Acid Reflux (GERD, Which Can Cause Throat Irritation and Muscle Tightness in the Neck)

Trigger Point Referral Pattern

Trigger points in the digastric refer pain to:

  • The jaw and under the chin (Can Mimic Dental or TMJ Pain)

  • The ear and side of the face (Mistaken for an Ear Infection or Sinus Pain)

  • The throat and front of the neck (Can Feel Like a Lump or Tightness in the Throat)

  • The back of the head (Can Mimic Occipital Headaches)

Pain from this muscle is often confused with throat infections, TMJ disorders, or nerve-related facial pain.

Differential Diagnosis

Digastric trigger points may be mistaken for:

  • TMJ Dysfunction (Jaw Pain, Clicking, and Difficulty Opening the Mouth)

  • Ear Infections (Otitis Media – Ear Pain and Fullness, Often Without Infection Present)

  • Tonsillitis or Throat Infections (Sore Throat, Swallowing Discomfort, and Tightness in the Neck)

  • Cervical Radiculopathy (Nerve Pain From the Neck That Can Cause Jaw and Facial Discomfort)

  • Trigeminal Neuralgia (Sharp, Shooting Facial Pain That Can Resemble Nerve Compression)

A thorough neck, jaw, and ear examination is crucial for proper diagnosis.

Associated Trigger Points

Digastric trigger points often co-exist with:

  • Masseter (Jaw Pain and Tension-Related Clenching)

  • Sternocleidomastoid (SCM) (Neck and Ear Pain, Often Related to Postural Issues)

  • Temporalis (Forehead and Temple Pain Related to Jaw Tension)

  • Suboccipital Muscles (Occipital Headaches and Base-of-Skull Tension)

Anatomy and Innervation

Muscle Origin Insertion Innervation
Digastric (Posterior Belly) Mastoid notch of the temporal bone Intermediate tendon of the hyoid bone Facial nerve (CN VII)
Digastric (Anterior Belly) Digastric fossa of the mandible Intermediate tendon of the hyoid bone Mandibular branch of the trigeminal nerve (CN V3)

The digastric has dual innervation from the facial nerve (CN VII) and mandibular nerve (CN V3), reflecting its involvement in both facial and jaw functions.

Patient Examination

A comprehensive examination should include:

  • Palpation: Identify tender nodules under the jawline and near the hyoid bone.

  • Jaw Mobility Testing: Assess pain or tightness when opening and closing the mouth.

  • Swallowing Assessment: Determine if discomfort increases with swallowing or speaking.

  • Neck and Postural Evaluation: Look for forward head posture or cervical muscle tightness.

Corrective Actions

Manual Therapy

  • Trigger Point Release: Apply gentle sustained pressure along the jawline and under the chin.

  • Myofascial Release: Stretch and mobilize the neck, jaw, and suprahyoid muscles.

Stretching

  • Jaw Stretch: Open the mouth wide and slowly close it while maintaining relaxed jaw positioning.

  • Neck Extension Stretch: Tilt the head back slightly while keeping the tongue on the roof of the mouth to stretch the digastric and suprahyoid muscles.

Strengthening Exercises

  • Jaw Control Drills: Practice slow, controlled mouth openings and closings to improve mobility.

  • Hyoid Stability Exercises: Lightly press the tongue against the roof of the mouth while swallowing to strengthen hyoid-supporting muscles.

Postural and Behavioral Adjustments

  • Avoid Excessive Jaw Clenching or Grinding (Use a Night Guard if Necessary)

  • Maintain Good Head and Neck Posture (Reduce Forward Head Positioning to Avoid Excessive Jaw Tension)

  • Limit Excessive Talking or Singing (Allow the Jaw Muscles to Recover if Overused)

Summary Table: Digastric Trigger Points

Field Details
Name & Area Digastric; Located under the jawline, spanning from the mastoid process to the mandible
Indications Jaw pain, ear pain, throat tightness, swallowing discomfort
Muscle Action Depresses the mandible, elevates the hyoid bone, assists in swallowing
Signs & Symptoms Pain under the chin, ear pain, tightness when swallowing, jaw clicking
Perpetuating Factors Jaw clenching, poor posture, excessive talking, GERD, dental procedures
Trigger Point Referral Jaw, ears, throat, back of the head
Differential Diagnosis TMJ dysfunction, ear infections, throat issues, trigeminal neuralgia
Associated Trigger Points Masseter, SCM, temporalis, suboccipital muscles
Anatomy & Innervation Facial nerve (CN VII), mandibular nerve (CN V3)
Corrective Actions Manual therapy, stretching, posture correction, jaw relaxation techniques

➡️ Learn more about Trigger Points

Sources:

  • Travell, J. G., & Simons, D. G. (1983). Myofascial Pain and Dysfunction: The Trigger Point Manual (2nd ed.). Williams & Wilkins.

  • Simons, D., & Travell, J. (1999). The Trigger Point Manual, Volume 2: The Lower Extremities. Williams & Wilkins.