Manual Muscle Test

Deep Neck Flexors (Longus Colli & Longus Capitis)

· 1. Neurological & Functional Insights

· Primary stabilizers of cervical lordosis and segmental control.

· High spindle density for fine motor control and postural regulation.

· Critical for reducing anterior shear forces at upper cervical levels.

· 2. Clinical Relevance

· Weakness common in forward-head posture and neck pain.

· Poor activation increases suboccipital and SCM overuse.

· Essential in cervical rehab and motor control retraining.

· 3. Origin

· Anterior vertebral bodies C1–T3

· 4. Insertion

· Occiput

· Anterior cervical vertebrae

· 5. Innervation

· C2–C6 ventral rami

· 6. Actions – Open Kinetic Chain (OKC)

· Cervical flexion

· Segmental stabilization

· 7. Actions – Closed Kinetic Chain (CKC)

· Stabilizes cervical spine during swallowing and breathing

· 8. Associated Ligaments

· Anterior longitudinal ligament connections

· 9. Associated Organs

Fascial:

· Prevertebral fascia

Viscerosomatic:

· C2–C6

TCM:

· Ren / Stomach meridian region

VM:

· Anterior cervical fascial restrictions influencing DNF activation

Neck Flexors

· 1. Neurological & Functional Insights

· Provide dynamic anterior support of the cervical spine.

· Coordinate with deep flexors for balanced forward movement.

· Important for controlling acceleration/deceleration motions.

· 2. Clinical Relevance

· Weakness leads to poor head control and increased cervical loading.

· Often inhibited in chronic neck pain.

· Overactivity of superficial flexors replaces deep motor control.

· 3. Origin

· Anterior cervical vertebrae

· Manubrium

· Clavicle

· 4. Insertion

· Occiput

· Mandible

· Upper ribs

· 5. Innervation

· C2–C6

· 6. Actions – Open Kinetic Chain (OKC)

· Cervical flexion

· 7. Actions – Closed Kinetic Chain (CKC)

· Head stabilization during lifting and breathing

· 8. Associated Ligaments

· Anterior cervical fascia

· 9. Associated Organs

Fascial:

· Superficial cervical fascia

Viscerosomatic:

· C2–C5

TCM:

· Stomach meridian region

VM:

· Neck fascial tightness altering flexor activation patterns

SCM (Sternocleidomastoid)

· 1. Neurological & Functional Insights

· Key driver of cervical rotation and contralateral control.

· Major contributor to respiratory accessory mechanics.

· Functions as a proprioceptive sensor for head positioning.

· 2. Clinical Relevance

· Often hypertonic in forward-head posture.

· Associated with headaches and proprioceptive imbalance.

· Overactive when deep neck flexors are inhibited.

· 3. Origin

· Manubrium

· Medial clavicle

· 4. Insertion

· Mastoid process

· Superior nuchal line

· 5. Innervation

· Accessory nerve (CN XI)

· C2–C3

· 6. Actions – Open Kinetic Chain (OKC)

· Contralateral rotation

· Ipsilateral sidebending

· Flexion (bilateral)

· 7. Actions – Closed Kinetic Chain (CKC)

· Elevates ribcage during forced respiration

· 8. Associated Ligaments

· Superficial cervical fascia

· 9. Associated Organs

Fascial:

· Carotid sheath fascia

Viscerosomatic:

· C2–C3

TCM:

· Gallbladder meridian region

VM:

· Thoracic inlet tension influencing SCM activation

Scalene Muscles (Anterior, Middle, Posterior)

· 1. Neurological & Functional Insights

· Key accessory breathing muscles stabilizing the first and second ribs.

· Important contributors to cervical stabilization during UE tasks.

· High spindle density supporting fine motor cervical adjustments.

· 2. Clinical Relevance

· Tightness contributes to thoracic outlet symptoms.

· Weakness decreases rib stability and breathing mechanics.

· Overactivity common in chronic stress breathing patterns.

· 3. Origin

· Transverse processes C2–C7

· 4. Insertion

· Ribs 1–2

· 5. Innervation

· C3–C8 ventral rami

· 6. Actions – Open Kinetic Chain (OKC)

· Cervical sidebending

· Assist flexion

· 7. Actions – Closed Kinetic Chain (CKC)

· Elevation of ribs 1–2 during respiration

· 8. Associated Ligaments

· Cervical transverse processes

· First rib fascia

· 9. Associated Organs

Fascial:

· Scalene fascia

· Thoracic inlet fascia

Viscerosomatic:

· C3–C8

TCM:

· Lung meridian region

VM:

· Thoracic inlet restrictions affecting scalene tension

Neck Extensors (Erector Spinae Cervicis Group)

· 1. Neurological & Functional Insights

· Primary extensors maintaining cervical lordosis.

· Control head posture against gravity.

· Important for shock absorption during gait and impact.

· 2. Clinical Relevance

· Tightness common in forward-head posture.

· Weakness leads to fatigue-related neck pain.

· Overactivity compensates for weak deep neck flexors.

· 3. Origin

· Spinous and transverse processes C2–T6

· 4. Insertion

· Occiput

· Cervical vertebrae

· 5. Innervation

· Dorsal rami C2–C8

· 6. Actions – Open Kinetic Chain (OKC)

· Cervical extension

· 7. Actions – Closed Kinetic Chain (CKC)

· Head stabilization during gait and load bearing

· 8. Associated Ligaments

· Nuchal ligament

· Facet joint capsules

· 9. Associated Organs

Fascial:

· Posterior cervical fascia

Viscerosomatic:

· C2–C8

TCM:

· Bladder meridian

VM:

· Posterior fascial restrictions influencing extensor firing

Suboccipital Muscles

· 1. Neurological & Functional Insights

· Critical controllers of upper cervical rotation and nodding.

· High density of proprioceptors for head position sensing.

· Connect movement with vestibular and visual systems.

· 2. Clinical Relevance

· Major source of cervicogenic headaches.

· Tightness linked with visual strain and breathing dysfunction.

· Overactivity compensates for DNF inhibition.

· 3. Origin

· Atlas and axis (C1–C2)

· 4. Insertion

· Occiput

· 5. Innervation

· Suboccipital nerve (C1)

· 6. Actions – Open Kinetic Chain (OKC)

· Upper cervical extension

· Fine rotation

· 7. Actions – Closed Kinetic Chain (CKC)

· Stabilizes head during visual tracking

· 8. Associated Ligaments

· Posterior atlanto-occipital membrane

· 9. Associated Organs

Fascial:

· Suboccipital triangle fascia

Viscerosomatic:

· C1–C2

TCM:

· Bladder meridian region

VM:

· Cranial fascial restrictions affecting suboccipital tone

Unilateral Neck Extension

· 1. Neurological & Functional Insights

· Represents oblique activation of extensors and rotators.

· Important for controlling diagonal and rotational cervical loading.

· Supports dynamic stabilization during unilateral tasks.

· 2. Clinical Relevance

· Asymmetry contributes to cervicogenic dizziness.

· Common compensation in whiplash injuries.

· Essential for restoring balanced cervical rotation strength.

· 3. Origin

· Posterior cervical musculature (multifidus, semispinalis, splenius)

· 4. Insertion

· Occiput

· Upper cervical vertebrae

· 5. Innervation

· Dorsal rami C2–C8

· 6. Actions – Open Kinetic Chain (OKC)

· Ipsilateral extension & rotation

· 7. Actions – Closed Kinetic Chain (CKC)

· Stabilizes cervical spine during one-sided arm tasks

· 8. Associated Ligaments

· Nuchal ligament

· Facet joint capsules

· 9. Associated Organs

Fascial:

· Posterior cervical fascia

Viscerosomatic:

· C2–C8

TCM:

· Bladder meridian region

VM:

· Posterior chain fascial imbalance affecting unilateral extension

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).

‍