Serratus Anterior Trigger Points

Introduction

The serratus anterior is a key upper body muscle responsible for scapular stabilization, rib movement, and shoulder function. When trigger points develop in this muscle, they can cause chest pain, shoulder blade tightness, and difficulty lifting the arm, often mimicking rotator cuff injuries, rib dysfunction, or intercostal neuralgia.

Name and Area

  • Name: Serratus Anterior

  • Area: Located on the side of the ribcage, running from the upper ribs (1–9) to the medial border of the scapula.

Indications

Serratus anterior trigger points may contribute to:

  • Pain under or around the shoulder blade (mistaken for rotator cuff dysfunction or scapular dyskinesis)

  • Pain that radiates to the side of the ribcage or chest (can mimic rib dysfunction or costochondritis)

  • Difficulty lifting the arm overhead (common in athletes, weightlifters, and swimmers)

  • Pain or discomfort when breathing deeply (can resemble intercostal neuralgia or lung-related pain)

  • Pain that increases with pushing movements (push-ups, bench press, or reaching forward)

  • Instability in the shoulder blade (feels like the shoulder blade "wings" out or moves uncontrollably)

Pain from this muscle is often mistaken for rib dysfunction, shoulder injuries, or nerve irritation.

Muscle Action

  • Protracts the Scapula: Moves the shoulder blade forward, essential for pushing and reaching movements.

  • Stabilizes the Scapula Against the Ribcage: Prevents scapular winging and supports shoulder mechanics.

  • Assists in Breathing: Helps expand the ribcage during deep inhalation.

The serratus anterior is crucial for upper body strength, breathing mechanics, and shoulder stability.

Signs and Symptoms

Individuals with serratus anterior trigger points often report:

  • Pain under the shoulder blade that feels like a deep, aching sensation

  • Pain or discomfort in the ribs that worsens with deep breathing or coughing

  • Difficulty reaching overhead or pushing against resistance

  • Pain that radiates to the chest or side of the ribcage (can mimic heart pain or intercostal strain)

  • Shoulder instability or scapular winging (can make overhead movements more difficult or unstable)

  • Pain that worsens with repetitive upper body movements (common in swimmers, boxers, and climbers)

Pain worsens with prolonged forward shoulder posture, pushing exercises, or deep breathing.

Perpetuating Factors

Common causes of serratus anterior trigger points include:

  • Repetitive overhead movements (swimming, boxing, rock climbing, or throwing sports)

  • Poor posture with rounded shoulders (common in desk workers and cyclists)

  • Weak upper back and rotator cuff muscles (forces the serratus anterior to overcompensate for stability)

  • Shallow breathing patterns (overuse of the serratus anterior for rib expansion and breathing mechanics)

  • Heavy lifting without proper shoulder engagement (common in weightlifters and athletes who overuse the chest and anterior shoulder muscles)

Trigger Point Referral Pattern

Trigger points in the serratus anterior refer pain to:

  • The side of the ribs and under the shoulder blade (Can Mimic Rib Dysfunction or Intercostal Pain)

  • The chest and upper arm (Mistaken for Pectoral Tightness or Nerve Compression)

  • The mid-back and lower scapular region (Can Resemble Thoracic Spine Dysfunction or Poor Shoulder Stability)

Pain from this muscle is often confused with rotator cuff dysfunction, intercostal neuralgia, or rib joint issues.

Differential Diagnosis

Serratus anterior trigger points may be mistaken for:

  • Rotator cuff dysfunction (shoulder pain and weakness, often worsens with overhead movements)

  • Thoracic outlet syndrome (pain, numbness, or weakness in the arm due to nerve or vascular compression)

  • Intercostal neuralgia (sharp, shooting rib pain that worsens with breathing or movement)

  • Costochondritis (inflammation of rib cartilage, causes tenderness in the ribcage and chest pain)

  • Pectoralis minor dysfunction (chest and shoulder pain, can contribute to rounded shoulders and postural imbalances)

A thorough shoulder, rib, and scapular movement examination is necessary to rule out these conditions.

Associated Trigger Points

Serratus anterior trigger points often co-exist with:

  • Pectoralis minor (anterior shoulder and chest tightness, can lead to forward shoulder posture)

  • Latissimus dorsi (shoulder and rib pain, common in overhead athletes and weightlifters)

  • Upper trapezius (neck and shoulder tension, can contribute to postural strain and shoulder dysfunction)

  • Rhomboids (scapular and upper back pain, common in those with poor shoulder posture and weak back muscles)

Anatomy and Innervation

Muscle Origin Insertion Innervation
Serratus Anterior Ribs 1–9 Medial border of the scapula Long thoracic nerve (C5–C7)

The serratus anterior is innervated by the long thoracic nerve (C5–C7), which also controls scapular stabilization and breathing mechanics.

Patient Examination

A comprehensive examination should include:

  • Palpation: Identify tender nodules along the ribs, under the scapula, and near the lateral chest wall.

  • Resisted Shoulder Protraction Testing: Assess pain and weakness when pushing the shoulder blade forward against resistance.

  • Scapular Mobility Testing: Check for scapular winging, instability, or excessive movement patterns.

  • Postural and Breathing Assessment: Look for forward shoulder posture, rib tightness, or restricted breathing mechanics.

Corrective Actions

Dry Needling

  • Dry needling can release trigger points in the serratus anterior, reducing scapular instability and improving shoulder function.

Manual Therapy

  • Trigger Point Release: Apply deep sustained pressure to tight spots along the ribs and scapula.

  • Myofascial Release: Helps improve circulation and reduce muscle tension around the ribcage and upper back.

Stretching

  • Wall Stretch for Serratus Anterior: Stand against a wall and press the arms upward to engage and stretch the serratus.

  • Rib Expansion Stretch: Take deep breaths while gently opening the chest and extending the arms outward.

Strengthening Exercises

  • Scapular Push-Ups (Wall or Floor): Strengthens the serratus anterior to improve shoulder stability.

  • Resisted Protraction with Bands: Helps engage and retrain proper scapular movement.

Postural and Movement Adjustments

  • Avoid excessive forward shoulder posture (maintain proper scapular alignment while sitting and standing)

  • Ensure proper form during pressing exercises (engage the serratus anterior to prevent shoulder impingement)

  • Incorporate diaphragmatic breathing exercises (encourages full rib expansion and reduces upper chest tightness)

Conclusion

The serratus anterior plays a crucial role in scapular stability, breathing, and shoulder function, but trigger points in this muscle can cause significant chest, rib, and upper back pain. By incorporating dry needling, manual therapy, stretching, and strengthening exercises, individuals can reduce pain, improve mobility, and prevent postural dysfunction.

➡️ Learn more about Trigger Points

➡️ Explore our Trigger Point Index

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.