External Abdominal Oblique Trigger Points

Introduction

The external abdominal oblique (EAO) is a key core muscle responsible for trunk rotation, lateral flexion, and core stability. When trigger points develop in this muscle, they can cause abdominal pain, lower back discomfort, and rib pain, often mimicking digestive issues, rib dysfunction, or hernias.

Name and Area

  • Name: External Abdominal Oblique (EAO)

  • Area: Located on the lateral abdomen, running from the lower ribs to the iliac crest and linea alba.

Indications

External abdominal oblique trigger points may contribute to:

  • Pain in the Lower Ribs and Upper Abdomen (Mistaken for Digestive Issues or Costochondritis)

  • Pain That Radiates to the Lower Back, Hip, or Groin (Can Mimic Kidney Pain or Hernias)

  • Stiffness or Tightness in the Side of the Abdomen (Feels Like a "Side Stitch")

  • Pain That Worsens With Twisting Movements (E.g., Golf, Tennis, or Yoga Twists)

  • Discomfort When Coughing, Sneezing, or Laughing

  • Pain When Sitting for Long Periods or After Strenuous Core Exercises

Pain from this muscle is often mistaken for internal organ issues, hernias, or rib dysfunction.

Muscle Action

  • Trunk Rotation: Twists the torso to the opposite side.

  • Lateral Flexion: Bends the torso sideways.

  • Core Stability: Works with the rectus abdominis and transverse abdominis to support posture and protect the spine.

The EAO is crucial for core strength, spinal alignment, and functional movement.

Signs and Symptoms

Individuals with external abdominal oblique trigger points often report:

  • Pain Along the Side of the Abdomen, Ribs, or Lower Back

  • Pain That Feels Like a Muscle Cramp or Side Stitch

  • Discomfort That Worsens With Twisting, Deep Breathing, or Coughing

  • Pain Radiating to the Groin or Hip (Mistaken for a Hernia or Hip Pain)

  • Stiffness in the Torso That Limits Rotational Movements

Pain worsens with twisting, prolonged sitting, or deep breathing.

Perpetuating Factors

Common causes of external abdominal oblique trigger points include:

  • Repetitive Twisting Movements (Golf, Tennis, Baseball, Martial Arts, Yoga Twists)

  • Poor Posture or Prolonged Sitting (Causes Muscle Shortening and Weakness)

  • Heavy Lifting With Poor Core Engagement (E.g., Weightlifting, Moving Furniture)

  • Chronic Coughing or Excessive Sneezing (Strains the Abdominal Muscles)

  • Overuse From Core Exercises (Sit-Ups, Russian Twists, Leg Raises Without Proper Form)

Trigger Point Referral Pattern

Trigger points in the external abdominal oblique refer pain to:

  • The lower ribs and side of the abdomen (Can Mimic Digestive or Gallbladder Issues)

  • The lower back and hip (Mistaken for Kidney Pain or Sciatic Nerve Issues)

  • The groin area (Can Resemble Hernias or Inguinal Strain)

Pain from this muscle is often confused with internal organ issues, hernias, or nerve compression.

Differential Diagnosis

External abdominal oblique trigger points may be mistaken for:

  • Digestive Issues (IBS, GERD, or Gallbladder Dysfunction – Due to Abdominal Discomfort and Cramping)

  • Hernias (Pain in the Groin or Lower Abdomen, Often Worse With Straining or Lifting)

  • Intercostal Neuralgia (Sharp, Shooting Pain Along the Ribs, Often Exacerbated by Breathing Movements)

  • Costochondritis (Inflammation of Rib Cartilage, Causing Chest or Side Pain)

  • Lower Back Pain (Quadratus Lumborum or Iliopsoas Dysfunction, Which Can Overlap With Abdominal Pain)

A thorough abdominal, rib, and lower back examination is necessary to rule out these conditions.

Associated Trigger Points

External abdominal oblique trigger points often co-exist with:

  • Rectus Abdominis (Abdominal Pain and Core Weakness)

  • Quadratus Lumborum (Lower Back and Side Pain, Affects Postural Stability)

  • Serratus Anterior (Rib and Side Pain, Affects Deep Breathing and Shoulder Stability)

  • Transverse Abdominis (Core Weakness and Instability, Can Lead to Low Back Strain)

Anatomy and Innervation

Muscle Origin Insertion Innervation
External Abdominal Oblique Lower 8 ribs Iliac crest, linea alba Intercostal nerves (T7–T11), Subcostal nerve (T12)

The EAO is innervated by the intercostal and subcostal nerves, which also control rib and abdominal movement.

Patient Examination

A comprehensive examination should include:

  • Palpation: Identify tender nodules along the side of the abdomen, ribs, and lower back.

  • Resisted Trunk Rotation Testing: Assess pain and weakness when twisting the torso against resistance.

  • Deep Breathing and Cough Testing: Evaluate discomfort during deep inhalation or forceful coughing.

  • Core Stability Testing: Look for weakness in the obliques and transverse abdominis.

Corrective Actions

Dry Needling

  • Dry needling can release trigger points in the external abdominal oblique, reducing muscle tension and improving mobility.

Manual Therapy

  • Trigger Point Release: Apply sustained pressure to tight areas along the abdomen and ribs.

  • Myofascial Release: Massage techniques to improve circulation and reduce abdominal tightness.

Stretching

  • Side Stretch: Reach overhead to the opposite side while standing to stretch the obliques and rib cage.

  • Twisting Stretch: Rotate the torso gently while seated or standing to improve mobility and relieve tension.

Strengthening Exercises

  • Side Planks: Strengthens the external obliques and stabilizes the core.

  • Russian Twists: Helps build rotational strength without excessive strain.

  • Pelvic Tilts: Encourages proper core activation and posture alignment.

Postural and Lifestyle Adjustments

  • Practice Proper Lifting Techniques (Engage the Core When Carrying Heavy Objects)

  • Use Proper Breathing Mechanics (Avoid Holding Breath While Exerting Effort)

  • Improve Sitting Posture (Avoid Slouching to Reduce Abdominal Compression)

Summary Table: External Abdominal Oblique Trigger Points

Field Details
Name & Area External Abdominal Oblique; Side of the abdomen, spanning ribs to iliac crest
Indications Rib, abdominal, lower back, and groin pain, core instability
Muscle Action Trunk rotation, lateral flexion, core stability
Signs & Symptoms Pain with twisting, deep breathing, or coughing; side cramps
Perpetuating Factors Repetitive twisting, poor posture, chronic coughing, excessive core workouts
Trigger Point Referral Ribs, abdomen, lower back, groin
Differential Diagnosis Hernias, digestive issues, intercostal neuralgia, lower back pain
Associated Trigger Points Rectus abdominis, quadratus lumborum, serratus anterior, transverse abdominis
Anatomy & Innervation Intercostal nerves (T7–T11), Subcostal nerve (T12)
Corrective Actions Dry needling, manual therapy, stretching, strengthening, posture correction

➡️ 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.