Internal Obliques Trigger Points

Introduction

The internal obliques are deep core muscles responsible for trunk rotation, side bending, and spinal stability. When trigger points develop in these muscles, they can cause abdominal pain, lower back discomfort, and rib tightness, often mimicking digestive issues, hernias, or intercostal neuralgia.

Name and Area

  • Name: Internal Obliques

  • Area: Located in the lateral abdomen, running from the inguinal ligament, iliac crest, and thoracolumbar fascia to the lower ribs and linea alba.

Indications

Internal oblique trigger points may contribute to:

  • Pain in the lower ribs and side of the abdomen (mistaken for rib dysfunction or digestive issues)

  • Pain that extends to the lower back and groin (can mimic hip flexor strain or hernia pain)

  • Tightness in the core that restricts trunk rotation and side bending

  • Pain that worsens with coughing, laughing, or deep breathing (common in those with rib or core dysfunction)

  • Pain or weakness in core movements (difficulty twisting, crunching, or stabilizing the spine)

  • Lower back or side pain that worsens after prolonged sitting or slouching

Pain from this muscle is often mistaken for digestive disorders, intercostal neuralgia, or abdominal strain.

Muscle Action

  • Rotates the Trunk: Twists the torso, essential for sports movements, reaching, and daily activities.

  • Laterally Flexes the Spine: Allows side bending and movement stability.

  • Supports the Core and Pelvis: Works with other core muscles to provide postural control and spinal stability.

The internal obliques are crucial for trunk mobility, core function, and spinal support.

Signs and Symptoms

Individuals with internal oblique trigger points often report:

  • Pain in the Side of the Abdomen That Feels Like a "Tight Band" or "Deep Ache"

  • Pain That Spreads to the Lower Back, Hip, or Groin (Can Feel Like a Pulled Muscle or Hernia Pain)

  • Tightness in the Core That Feels Like a "Stiffness" When Twisting or Bending

  • Pain That Increases with Deep Breathing, Sneezing, or Laughing

  • Weakness or Discomfort When Performing Side Planks, Twisting Movements, or Core Exercises

  • Pain That Worsens with Poor Posture, Slouching, or Excessive Core Flexion

Pain worsens with repetitive twisting, poor posture, or prolonged core engagement.

Perpetuating Factors

Common causes of internal oblique trigger points include:

  • Overuse in Twisting Sports (Common in Golfers, Tennis Players, and Baseball Players)

  • Repetitive Core Exercises Without Proper Engagement (Can Cause Muscle Strain and Dysfunction)

  • Poor Sitting Posture (Slouching or Prolonged Sitting Can Lead to Core Tightness and Weakness)

  • Chronic Coughing or Shallow Breathing (Can Overuse the Internal Obliques for Respiratory Function)

  • Pregnancy or Abdominal Surgery (Can Lead to Core Imbalances and Muscle Tension)

Trigger Point Referral Pattern

Trigger points in the internal obliques refer pain to:

  • The side of the abdomen and lower ribs (can mimic rib dysfunction or digestive pain)

  • The lower back and groin (mistaken for hernia or hip flexor dysfunction)

  • The upper pelvis and iliac crest (can resemble lower core instability or SI joint pain)

Pain from this muscle is often confused with abdominal strain, intercostal pain, or lower back dysfunction.

Differential Diagnosis

Internal oblique trigger points may be mistaken for:

  • Intercostal Neuralgia (Sharp, Shooting Pain Along the Ribs, Worsens with Breathing or Movement)

  • Abdominal Strain (Pain and Tightness in the Core, Common in Overuse or Injury Situations)

  • Hernias (Pain and Bulging in the Lower Abdomen, Often Worsens with Straining or Lifting)

  • Irritable Bowel Syndrome (IBS) (Abdominal Pain and Discomfort, Often with Digestive Symptoms)

  • Lower Back Dysfunction (Can Cause Radiating Pain to the Side or Front of the Core)

A thorough core, rib, and pelvic assessment is necessary to rule out these conditions.

Associated Trigger Points

Internal oblique trigger points often co-exist with:

  • External Oblique (Upper Core and Rib Pain, Affects Trunk Stability and Rotation)

  • Rectus Abdominis (Lower Core and Rib Pain, Can Contribute to Spinal Dysfunction and Postural Imbalances)

  • Quadratus Lumborum (Lower Back and Pelvic Pain, Affects Core Stability and Hip Movement)

  • Diaphragm (Upper Abdominal and Rib Pain, Can Affect Breathing and Postural Control)

Anatomy and Innervation

Muscle Origin Insertion Innervation
Internal Obliques Inguinal ligament, iliac crest, thoracolumbar fascia Lower ribs (10–12), linea alba Lower intercostal nerves (T7–T12), iliohypogastric and ilioinguinal nerves (L1)

The internal obliques are innervated by the lower intercostal nerves and iliohypogastric/ilioinguinal nerves, which also control abdominal movement, core stability, and spinal function.

Patient Examination

A comprehensive examination should include:

  • Palpation: Identify tender nodules along the lateral abdomen, lower ribs, and iliac crest.

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

  • Breathing and Core Activation Testing: Look for shallow breathing, core weakness, or excessive abdominal tension.

  • Pelvic and Lower Back Mobility Testing: Rule out SI joint dysfunction, hip flexor tightness, or postural imbalances.

Corrective Actions

Dry Needling

  • Dry needling can release trigger points in the internal obliques, reducing core tightness and improving trunk flexibility.

Manual Therapy

  • Trigger Point Release: Apply deep sustained pressure to tight spots in the lateral abdomen and ribs.

  • Myofascial Release: Helps improve circulation and reduce muscle tension in the abdominal wall.

Stretching

  • Side Stretch (Lateral Flexion Stretch): Helps release tension in the obliques and improve spinal mobility.

  • Seated Twisting Stretch: Encourages core flexibility and rib mobility.

Strengthening Exercises

  • Side Planks: Strengthens the internal obliques for core stability and trunk support.

  • Pallof Press: Helps engage the obliques in a controlled manner, improving stability.

Postural and Lifestyle Adjustments

  • Avoid Prolonged Slouching (Maintain Proper Sitting Posture to Prevent Core Tightness)

  • Ensure Proper Breathing Mechanics (Encourages Full Rib Expansion and Reduces Excessive Abdominal Tension)

  • Use Proper Lifting Techniques (Prevents Excessive Strain on the Internal Obliques and Lower Back)

Conclusion

The internal obliques play a crucial role in core function, trunk movement, and spinal stability, but trigger points in these muscles can cause significant abdominal, lower back, and rib pain. By incorporating dry needling, manual therapy, stretching, and core stability exercises, individuals can reduce pain, improve mobility, and prevent core dysfunction.

➡️ 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.