Manual Muscle Test

External Oblique

· 1. Neurological & Functional Insights

· Major contributor to trunk rotation and lateral flexion.

· Integrates thorax–pelvis coupling through fascial slings.

· Essential for intra-abdominal pressure regulation.

· 2. Clinical Relevance

· Weakness decreases rotational power and spinal stability.

· Tightness affects rib mechanics and breathing.

· Crucial in gait and athletic trunk control.

· 3. Origin

· Ribs 5–12

· 4. Insertion

· Linea alba

· Iliac crest

· Pubic tubercle

· 5. Innervation

· Intercostal nerves (T7–T12)

· 6. Actions – Open Kinetic Chain (OKC)

· Contralateral rotation

· Ipsilateral sidebend

· Trunk flexion

· 7. Actions – Closed Kinetic Chain (CKC)

· Pelvic rotation during gait

· Thoracic stabilization

· 8. Associated Ligaments

· Thoracolumbar fascia

· 9. Associated Organs

Fascial:

· Abdominal wall fascia

Viscerosomatic:

· T7–T12

TCM:

· Gallbladder meridian region

VM:

· Rib mobility affecting EO recruitment

Internal Oblique

· 1. Neurological & Functional Insights

· Primary driver of ipsilateral trunk rotation.

· Works synergistically with TVA for abdominal pressurization.

· Important stabilizer of lumbar spine.

· 2. Clinical Relevance

· Weakness leads to decreased trunk power.

· Tightness influences rib depression and breathing mechanics.

· Important in core rehab and rotational sports.

· 3. Origin

· Iliac crest

· Thoracolumbar fascia

· 4. Insertion

· Linea alba

· Ribs 10–12

· 5. Innervation

· Intercostal nerves T6–T12

· Iliohypogastric nerve

· 6. Actions – Open Kinetic Chain (OKC)

· Ipsilateral rotation

· Trunk flexion

· Sidebending

· 7. Actions – Closed Kinetic Chain (CKC)

· Pelvic control during rotation

· 8. Associated Ligaments

· Thoracolumbar fascia

· 9. Associated Organs

Fascial:

· Abdominal fascia

Viscerosomatic:

· T6–T12

TCM:

· Spleen meridian region

VM:

· Visceral restrictions altering IO tension

Rectus Abdominis

· 1. Neurological & Functional Insights

· Primary trunk flexor with key role in spinal stability.

· Segmental structure allows distributed load control.

· Important counterbalance to spinal extensors.

· 2. Clinical Relevance

· Weakness leads to lumbar extension bias.

· Tightness reduces rib mobility.

· Critical in postural and athletic mechanics.

· 3. Origin

· Pubic crest

· Pubic symphysis

· 4. Insertion

· Costal cartilages 5–7

· Xiphoid process

· 5. Innervation

· Intercostal nerves T6–T12

· 6. Actions – Open Kinetic Chain (OKC)

· Trunk flexion

· Posterior pelvic tilt

· 7. Actions – Closed Kinetic Chain (CKC)

· Stabilizes thorax during UE and LE tasks

· 8. Associated Ligaments

· Linea alba

· 9. Associated Organs

Fascial:

· Rectus sheath

Viscerosomatic:

· T6–T12

TCM:

· Stomach meridian

VM:

· Abdominal wall fascial tension affecting RA activity

Thoracic Paravertebral Muscles

· 1. Neurological & Functional Insights

· Provide thoracic extension and segmental stability.

· Important for rib mechanics during breathing.

· Major contributors to posture and spinal control.

· 2. Clinical Relevance

· Often inhibited in kyphotic posture.

· Overactivity contributes to mid-back stiffness.

· Essential for thoracic rotation and extension.

· 3. Origin

· Thoracic transverse & spinous processes

· 4. Insertion

· Adjacent vertebrae & ribs

· 5. Innervation

· Dorsal rami T1–T12

· 6. Actions – Open Kinetic Chain (OKC)

· Thoracic extension

· Rotation

· Sidebending

· 7. Actions – Closed Kinetic Chain (CKC)

· Postural stabilization in gait and lifting

· 8. Associated Ligaments

· Thoracic facet capsules

· Costovertebral ligaments

· 9. Associated Organs

Fascial:

· Posterior thoracic fascia

Viscerosomatic:

· T1–T12

TCM:

· Bladder meridian

VM:

· Thoracic fascial restrictions influencing paraspinal tone

Module references

· Standring S, ed. Gray’s Anatomy: The Anatomical Basis of Clinical Practice. Elsevier.

· Neumann DA. Kinesiology of the Musculoskeletal System: Foundations for Rehabilitation. Elsevier.

· Kendall FP et al. Muscles: Testing and Function with Posture and Pain. Lippincott Williams & Wilkins.

· Netter FH. Atlas of Human Anatomy. Elsevier.

· Barral JP, Mercier P. Visceral Manipulation. Eastland Press (framework-specific associations).

· Deadman P, Al-Khafaji M, Baker K. A Manual of Acupuncture. Journal of Chinese Medicine Publications (traditional channel associations).

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