OIANs of all the muscles

Authors

Affiliations

Nate Yomogida, PT, DPT

Doctor of Physical Therapy

B.S. in Kinesiology

Chloë Kerstein, PT, DPT

Doctor of Physical Therapy

B.A. in Neuroscience

Back

Suboccipitals

• Rectus Capitis Posterior Major
• Rectus Capitis Posterior Minor
• Obliquus Capitis Superior
• Obliquus Capitis Inferior

Warning: No 'path' link found for variable 'nan' in YAML data.

Table 1: Suboccipital Muscles

Muscle	Origin	Insertion	Innervation	Action
Obliquus capitis inferior
Obliquus capitis superior
Rectus capitis posterior major				UNIL: I/L head rotation
Rectus Capitis Posterior Minor	C1 (posterior tubercle)	Occipital bone (inferior nuchal line, inner 1/3)	Suboccipital N.	BIL: Extend head UNIL: I/L head rotation

Prevertebral Muscles

• Longus capitis
• Longus Colli Cervicis
• Rectus Capitis anterior
• Rectus Capitis Lateralis

Table 2: Prevertebral Muscles

Muscle	Origin	Insertion	Innervation	Action
Anterior Intertransversarii cervicis	C2-C7 Anterior tubercle of superior segment	C2-C7 Anterior tubercle of inferior segment	Spinal nn. (anterior rami)	Bilateral: Cervical extension and stabilization, lumbar extension and stabilization Unilateral: Cervical extension and ipsilateral sidebend, Lumbar extension and ipsilateral sidebend
Anterior scalene	Anterior tubercle of TP of C3-C6	Scalene tubercle of 1st Rib	Anterior Rami C4 - C6	Mobile ribs: Elevates ribs during forced inspiration Fixed ribs (unilateral): I/L C/s sidebend (unilateral) Fixed ribs (bil): C/s flexion, Cervical lateral stabilization
Longus capitis	C3-C6 Anterior tubercle of TP	Occipital bone (basilar part)	Anterior rami C1 - C3	OA Joint: Head flexion
Longus colli cervicis	C5-T3 Anterior surface of vertebral body	C2-C4 Anterior surface	Anterior rami C2 - C6	Unilateral: C/L sidebend, C/L rotation Bilateral: Forward flexion
Middle scalene	C1-C2 TP Posterior tubercle of TP of C3-C7	1st Rib (posterior to groove for subclavian a.)	Anterior Rami C3 - C8	Mobile ribs: Elevates ribs during forced inspiration Fixed ribs (unilateral): I/L C/s sidebend (unilateral) Fixed ribs (bil): C/s flexion, Cervical lateral stabilization
Posterior intertransversarii cervicis	C2-C7 Posterior tubercle of superior segment	C2-C7 Posterior tubercle of superior segment	Spinal nn. (posterior rami)	Bilateral: Cervical extension and stabilization, lumbar extension and stabilization Unilateral: Cervical extension and ipsilateral sidebend, Lumbar extension and ipsilateral sidebend
Posterior scalene	Posterior tubercle of TP of C5-C7	2nd Rib (outer surface)	Anterior Rami C6 - C8	Mobile ribs: Elevates ribs during forced inspiration Fixed ribs (unilateral): I/L C/s sidebend (unilateral) Fixed ribs (bil): C/s flexion, Cervical lateral stabilization
Rectus capitis anterior	C1 Lateral mass	Occipital bone (basilar part)	Anterior rami C1	Unilateral: OAJ ipsilateral sidebend
Rectus capitis lateralis	C1 TP	Occipital bone (basilar part and lateral to occipital condyles)	Anterior rami C1	Unilateral: OAJ ipsilateral sidebend

Superficial intrinsic back Muscles

• Serratus posterior superior
• Serratus posterior inferior
• Splenius capitis
• Splenius cervicis

Table 3: Superficial Intrinsic Back Muscles

Muscle	Origin	Insertion	Innervation	Action
Serratus posterior inferior
Serratus posterior superior
Splenius capitis	Nuchal lig. C7-T4 SP	Lateral third of nuchal line Mastoid process	Spinal nn. Posterior rami (lateral br.) C1 - C6	Bilateral: Head and neck extension Unilateral: I/L sidebend, I/L rotation
Splenius cervicis	T3-T7 SP	C1-C4 SP	Spinal nn. Posterior rami (lateral br.) C1 - C6	Bilateral: Head and neck extension Unilateral: I/L sidebend, I/L rotation

Intermediate intrinsic back muscles (Erector Spinae)

Iliocostalis

• Iliocostalis Cervicis
• Iliocostalis Thoracis
• Iliocostalis lumborum

Longissimus

• Longissimus Capitis
• Longissimus Cervicis
• Longissimus Thoracis

Spinalis

• Spinalis Cervicis
• Spinalis Thoracis

Table 4: Intermediate intrinsic back muscles

Muscle	Origin	Insertion	Innervation	Action
Iliocostalis cervicis	Ribs 3-7	C4-C6 TP	Spinal nn. Posterior rami (lateral br.) C8 - L1	Bilateral: Extends spine Unilateral: Spine ipsilateral sidebend
Iliocostalis lumborum	Sacrum Iliac crest Thoracolumbar fascia (posterior layer)	Ribs 6-12 Upper lumbar TP Thoracolumbar fascia (posterior layer)	Spinal nn. Posterior rami (lateral br.) C8 - L1	Bilateral: Extends spine Unilateral: Spine ipsilateral sidebend
Iliocostalis thoracis	Ribs 7-12	Ribs 1-6	Spinal nn. Posterior rami (lateral br.) C8 - L1	Bilateral: Extends spine Unilateral: Spine ipsilateral sidebend
Longissimus capitis	T1-T3 TP C4-C7 TP & articular process	Mastoid process	Spinal nn. Posterior rami (lateral br.) C1 - C5	Bilateral: Head extension Unilateral: Ipsilateral head sidebend, Ipsilateral rotation
Longissimus cervicis	T1-T6 TP	C2-C5 TP	Spinal nn. Posterior rami (lateral br.) C1 - C5	Bilateral: Extends spine Unilateral: Ipsilateral spine sidebend
Longissimus thoracis	Sacrum Iliac crest Lumbar vertebrae SP Lower thoracic TP	2-12 Ribs Thoracic TP Lumbar TP	Spinal nn. Posterior rami (lateral br.) C1 - C5	Bilateral: Extends spine Unilateral: Ipsilateral spine sidebend
Spinalis cervicis	C5-T2 SP	C5-T2 SP	Spinal nn. Posterior rami (lateral br.)	Bilateral: Cervical extension, Thoracic extension Unilateral: Cervical ipsilateral sidebend, Thoracic ipsilateral sidebend
Spinalis thoracis	T10-L3 SP and Lateral surfaces	T2-8 SP & Lateral surfaces	Spinal nn. Posterior rami (lateral br.)	Bilateral: Cervical extension, Thoracic extension Unilateral: Cervical ipsilateral sidebend, Thoracic ipsilateral sidebend

Transversospinalis Muscles

• Rotatores Breves
• Rotatores Longi
• Multifidi
• Semispinalis Capitis
• Semispinalis Cervicis
• Semispinalis Thoracis

Table 5: Transversospinalis muscles

Muscle	Origin	Insertion	Innervation	Action

Deep Segmental Back Muscles

• Interspinales Cervicis
• Interspinales Lumbora

Warning: No 'path' link found for variable 'ref-medial-intertransversarii-cervices' in YAML data.

Table 6: Transversospinalis muscles

Muscle	Origin	Insertion	Innervation	Action
Anterior Intertransversarii cervicis	C2-C7 Anterior tubercle of superior segment	C2-C7 Anterior tubercle of inferior segment	Spinal nn. (anterior rami)	Bilateral: Cervical extension and stabilization, lumbar extension and stabilization Unilateral: Cervical extension and ipsilateral sidebend, Lumbar extension and ipsilateral sidebend
Interspinales cervicis	C1-C7 SP of superior segment	C1-C7 SP of inferior segment	Spinal nn. Posterior rami	Cervical: Extension Lumbar: Extension
Interspinales lumbora	L1-L5 SP of superior segment	L1-L5 SP of inferior segment	Spinal nn. Posterior rami	Bilateral: Cervical extension and stabilization, lumbar extension and stabilization Unilateral: Cervical extension and ipsilateral sidebend, Lumbar extension and ipsilateral sidebend
Lateral intertransversarii lumbora	L1-L5 TP of superior segment	L1-L5 TP of inferior segment	Spinal nn. (anterior rami)	Bilateral: Cervical extension and stabilization, lumbar extension and stabilization Unilateral: Cervical extension and ipsilateral sidebend, Lumbar extension and ipsilateral sidebend
Levatores cosatrum breves	C7-T11 TP	Costal angle of next inferior rib	Spinal nn. (posterior rami)	Bilateral: Thoracic extension Unilateral: Thoracic ipsilateral sidebend, contralateral rotation
Levatores costarum longi	C7-T11 TP	Costal angle of rib 2 segments inferior	Spinal nn. (posterior rami)	Bilateral: Thoracic extension Unilateral: Thoracic ipsilateral sidebend, contralateral rotation
Medial intertransversarii cervicis
Medial intertransversarii lumbora	L1-L5 Mammillary process of superior segment	L1-L5 Mammillary process of inferior segment	Spinal nn. (posterior rami)	Bilateral: Cervical extension and stabilization, lumbar extension and stabilization Unilateral: Cervical extension and ipsilateral sidebend, Lumbar extension and ipsilateral sidebend
Posterior intertransversarii cervicis	C2-C7 Posterior tubercle of superior segment	C2-C7 Posterior tubercle of superior segment	Spinal nn. (posterior rami)	Bilateral: Cervical extension and stabilization, lumbar extension and stabilization Unilateral: Cervical extension and ipsilateral sidebend, Lumbar extension and ipsilateral sidebend

Thorax

Abdominal Wall

Warning: No 'path' link found for variable 'nan' in YAML data.
Warning: No 'path' link found for variable 'nan' in YAML data.
Warning: No 'path' link found for variable 'nan' in YAML data.
Warning: No 'path' link found for variable 'nan' in YAML data.
Warning: No 'path' link found for variable 'nan' in YAML data.
Warning: No 'path' link found for variable 'nan' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.
Warning: No 'action' link found for variable 'None' in YAML data.

Table 7: Abdominal Wall Muscles

Muscle	Origin	Insertion	Innervation	Action
External oblique
Iliacus	Iliac Fossa	Lesser Trochanter	Femoral n. L2 - L3	Hip: Flexion, ER L/S (UNIL contraction on fixed femur): I/L spine sidebend L/S (BIL contraction): Raises trunk from supine position
Internal oblique
Psoas Major	T12-L4 and associated IV discs L1-L5 TP	Lesser Trochanter	Lumbar Plexus Direct Br. L1 - L3	Hip: Flexion, ER L/S (unilateral contraction with femur fixed): I/L spine sidebend L/S (bilateral contraction): Raises trunk from supine position
Psoas Minor	T12, L1 vertebrae (lateral aspect) and IVD	Pectineal Line Iliopubic ramus Iliac fascia Inguinal ligament	Spinal nn. L1 - L3	Trunk: Weak flexion
Pyramidalis			T12	Tenses linea alba
Quadratus lumborum
Rectus abdominis				Trunk: Flexion Abdomen: Compression Pelvic: stabilization
Transversus abdominis

Pelvis & Perineum

Pelvic Floor

Warning: No 'path' link found for variable 'nan' in YAML data.
Warning: No 'path' link found for variable 'nan' in YAML data.
Warning: No 'path' link found for variable 'nan' in YAML data.

Table 8: Pelvic Floor Muscles

Muscle	Origin	Insertion	Innervation	Action
Iliococcygeus
Obturator Internus	Obturator membrane and its bony boundaries	Medial surface of Greater Trochanter	Nerve to Obturator internus L5 - S1	Hip: ER, Extension, Abduction, Stabilization
Piriformis	Anterior Sacrum	Apex of the Greater Trochanter	Sacral Plexus Direct Br. S1 - S2	Hip (at <60° flexion): ER Hip: Abduction, Extension, Stabilization Hip (at ≥60° flexion): IR
Pubococcygeus
Puborectalis

Perineum

Warning: No 'path' link found for variable 'nan' in YAML data.
Warning: No 'path' link found for variable 'nan' in YAML data.
Warning: No 'path' link found for variable 'nan' in YAML data.
Warning: No 'path' link found for variable 'nan' in YAML data.
Warning: No 'path' link found for variable 'nan' in YAML data.
Warning: No 'path' link found for variable 'nan' in YAML data.

Table 9: Perineum Muscles

Muscle	Origin	Insertion	Innervation	Action
Bulbospongiosus
Deep transverse perineal
External anal sphincter
External urethral sphincter
Ischiocavernosus
Superficial transverse perineal

Head and Neck

Muscles of Facial Expression

Muscle	Origin	Insertion	Nerve	Action
Calvaria
Occipitofrontalis (Frontal belly)	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/occipitofrontalis.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/occipitofrontalis.html#insertion	?var:ref-occipitofrontalis.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/occipitofrontalis.html#action
Palpebral Fissure and Nose
Procerus	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/procerus.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/procerus.html#insertion	?var:ref-procerus.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/procerus.html#action
Orbicularis Oculi	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/orbicularis_oculi.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/orbicularis_oculi.html#insertion	?var:ref-orbicularis-oculi.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/orbicularis_oculi.html#action
Nasalis	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/nasalis.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/nasalis.html#insertion	?var:ref-nasalis.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/nasalis.html#action
Levator Labii superioris alaeque nasi	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/levator_labii_superioris_alaeque_nasi.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/levator_labii_superioris_alaeque_nasi.html#insertion	?var:ref-levator-labii-superioris-alaeque-nasi.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/levator_labii_superioris_alaeque_nasi.html#action
Ear
Anterior Auricular Muscle	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/anterior_auricular_muscle.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/anterior_auricular_muscle.html#insertion	?var:ref-anterior-auricular-muscle.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/anterior_auricular_muscle.html#action

Muscles of Facial Expression OIAN

Muscle	Origin	Insertion	Nerve	Action
Superior Auricular Muscle	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/superior_auricular_muscle.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/superior_auricular_muscle.html#insertion	?var:ref-superior-auricular-muscle.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/superior_auricular_muscle.html#action
Posterior Auricular Muscle	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/superior_auricular_muscle.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/superior_auricular_muscle.html#insertion	?var:ref-posterior-auricular-muscle.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/superior_auricular_muscle.html#action
Mouth
Zygomaticus major	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/zygomaticus_major.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/zygomaticus_major.html#insertion	?var:ref-zygomaticus-major.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/zygomaticus_major.html#action
Zygomaticus Minor	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/zygomaticus_minor.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/zygomaticus_minor.html#insertion	?var:ref-zygomaticus-minor.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/zygomaticus_minor.html#action
Levator Labii superioris alaeque nasi	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/levator_labii_superioris_alaeque_nasi.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/levator_labii_superioris_alaeque_nasi.html#insertion	?var:ref-levator-labii-superioris-alaeque-nasi.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/levator_labii_superioris_alaeque_nasi.html#action
Levator Labii superioris	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/levator_labii_superioris.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/levator_labii_superioris.html#insertion	?var:ref-levator-labii-superioris.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/levator_labii_superioris.html#action
Depressor labii inferioris	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/depressor_labii_inferioris.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/depressor_labii_inferioris.html#insertion	?var:ref-depressor-labii-inferioris.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/depressor_labii_inferioris.html#action
Levator Anguli Oris	?var:ref-levator-anguli-oris.origin	?var:ref-levator-anguli-oris.insertion	?var:ref-levator-anguli-oris.nerve	?var:ref-levator-anguli-oris.action
Depressor Anguli Oris	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/depressor_anguli_oris.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/depressor_anguli_oris.html#insertion	?var:ref-depressor-anguli-oris.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/depressor_anguli_oris.html#action
Buccinator	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/buccinator.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/buccinator.html#insertion	?var:ref-buccinator.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/buccinator.html#action
Orbicularis Oris	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/orbicularis_oris.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/orbicularis_oris.html#insertion	?var:ref-orbicularis-oris.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/orbicularis_oris.html#action
Risorius	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/risorius.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/risorius.html#insertion	?var:ref-risorius.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/risorius.html#action
Mentalis muscle	?var:ref-mentalis-muscle.origin	?var:ref-mentalis-muscle.insertion	?var:ref-mentalis-muscle.nerve	?var:ref-mentalis-muscle.action
Neck
Platysma muscle	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/platysma.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/platysma.html#insertion	?var:ref-platysma.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Facial Expression/platysma.html#action

Figure 1: Muscles of Facial expression¹

Muscles of Mastication

Muscles of Mastication OIAN

Muscle	Origin	Insertion	Nerve	Action
Masseter muscle	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Mastication/masseter.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Mastication/masseter.html#insertion	?var:ref-masseter.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Mastication/masseter.html#action
Temporalis muscle	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Mastication/temporalis.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Mastication/temporalis.html#insertion	?var:ref-temporalis.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Mastication/temporalis.html#action
Lateral Pterygoid	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Mastication/lateral_pterygoid.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Mastication/lateral_pterygoid.html#insertion	?var:ref-lateral-pterygoid.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Mastication/lateral_pterygoid.html#action
Medial Pterygoid	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Mastication/medial_pterygoid.html#origin	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Mastication/medial_pterygoid.html#insertion	?var:ref-medial-pterygoid.nerve	/The Archive/Anatomy/Skeletal Muscles/Head and Neck/Muscles of Mastication/medial_pterygoid.html#action

Muscles of the Neck

Superficial Neck Muscles

• Platysma
• Sternocleidomastoid
• Trapezius

Table 10: Anterior Axioappendicular Muscles

Muscle	Origin	Insertion	Innervation	Action
Platysma
Sternocleidomastoid	Manubrium Medial third of Clavicle	Mastoid process Superior nuchal line	CN XI Accessory n. Cervical plexus C1 - C4	Unilateral: I/L cervical sidebend, C/L cervical rotation Bilateral: Head extension, Cervical Flexion, Assists in respiration, Prevents posterior translation during mastication SCJ stabilization
Upper trapezius	Occiput SP C1-C7	lateral 1/3 of Clavicle	Accessory n. (CN XI) C3 - C4	Scapula: Elevation, Upward rotatino Neck: I/L sidebend, C/L Rotation

Nuchal muscles (Intrinsic back muscles)

• Semispinalis Capitis
• Semispinalis Cervicis
• Splenius Capitis
• Splenius Cervicis
• Longissimus Capitis
• Longissimus Cervicis
• Iliocostalis cervicis
• Rectus Capitis Posterior Major
• Rectus Capitis Posterior Minor
• Obliquus Capitis Superior
• Obliquus Capitis Inferior

Table 11: Superficial Intrinsic back muscles

Muscle	Origin	Insertion	Innervation	Action
Serratus posterior inferior
Serratus posterior superior
Splenius capitis	Nuchal lig. C7-T4 SP	Lateral third of nuchal line Mastoid process	Spinal nn. Posterior rami (lateral br.) C1 - C6	Bilateral: Head and neck extension Unilateral: I/L sidebend, I/L rotation
Splenius cervicis	T3-T7 SP	C1-C4 SP	Spinal nn. Posterior rami (lateral br.) C1 - C6	Bilateral: Head and neck extension Unilateral: I/L sidebend, I/L rotation

Table 12: Intermediate Intrinsic back muscles

Muscle	Origin	Insertion	Innervation	Action
Iliocostalis cervicis	Ribs 3-7	C4-C6 TP	Spinal nn. Posterior rami (lateral br.) C8 - L1	Bilateral: Extends spine Unilateral: Spine ipsilateral sidebend
Iliocostalis lumborum	Sacrum Iliac crest Thoracolumbar fascia (posterior layer)	Ribs 6-12 Upper lumbar TP Thoracolumbar fascia (posterior layer)	Spinal nn. Posterior rami (lateral br.) C8 - L1	Bilateral: Extends spine Unilateral: Spine ipsilateral sidebend
Iliocostalis thoracis	Ribs 7-12	Ribs 1-6	Spinal nn. Posterior rami (lateral br.) C8 - L1	Bilateral: Extends spine Unilateral: Spine ipsilateral sidebend
Longissimus capitis	T1-T3 TP C4-C7 TP & articular process	Mastoid process	Spinal nn. Posterior rami (lateral br.) C1 - C5	Bilateral: Head extension Unilateral: Ipsilateral head sidebend, Ipsilateral rotation
Longissimus cervicis	T1-T6 TP	C2-C5 TP	Spinal nn. Posterior rami (lateral br.) C1 - C5	Bilateral: Extends spine Unilateral: Ipsilateral spine sidebend
Longissimus thoracis	Sacrum Iliac crest Lumbar vertebrae SP Lower thoracic TP	2-12 Ribs Thoracic TP Lumbar TP	Spinal nn. Posterior rami (lateral br.) C1 - C5	Bilateral: Extends spine Unilateral: Ipsilateral spine sidebend
Spinalis cervicis	C5-T2 SP	C5-T2 SP	Spinal nn. Posterior rami (lateral br.)	Bilateral: Cervical extension, Thoracic extension Unilateral: Cervical ipsilateral sidebend, Thoracic ipsilateral sidebend
Spinalis thoracis	T10-L3 SP and Lateral surfaces	T2-8 SP & Lateral surfaces	Spinal nn. Posterior rami (lateral br.)	Bilateral: Cervical extension, Thoracic extension Unilateral: Cervical ipsilateral sidebend, Thoracic ipsilateral sidebend

Warning: No 'path' link found for variable 'ref-medial-intertransversarii-cervices' in YAML data.

Table 13: Deep Intrinsic back muscles

Muscle	Origin	Insertion	Innervation	Action
Anterior Intertransversarii cervicis	C2-C7 Anterior tubercle of superior segment	C2-C7 Anterior tubercle of inferior segment	Spinal nn. (anterior rami)	Bilateral: Cervical extension and stabilization, lumbar extension and stabilization Unilateral: Cervical extension and ipsilateral sidebend, Lumbar extension and ipsilateral sidebend
Interspinales cervicis	C1-C7 SP of superior segment	C1-C7 SP of inferior segment	Spinal nn. Posterior rami	Cervical: Extension Lumbar: Extension
Interspinales lumbora	L1-L5 SP of superior segment	L1-L5 SP of inferior segment	Spinal nn. Posterior rami	Bilateral: Cervical extension and stabilization, lumbar extension and stabilization Unilateral: Cervical extension and ipsilateral sidebend, Lumbar extension and ipsilateral sidebend
Lateral intertransversarii lumbora	L1-L5 TP of superior segment	L1-L5 TP of inferior segment	Spinal nn. (anterior rami)	Bilateral: Cervical extension and stabilization, lumbar extension and stabilization Unilateral: Cervical extension and ipsilateral sidebend, Lumbar extension and ipsilateral sidebend
Levatores cosatrum breves	C7-T11 TP	Costal angle of next inferior rib	Spinal nn. (posterior rami)	Bilateral: Thoracic extension Unilateral: Thoracic ipsilateral sidebend, contralateral rotation
Levatores costarum longi	C7-T11 TP	Costal angle of rib 2 segments inferior	Spinal nn. (posterior rami)	Bilateral: Thoracic extension Unilateral: Thoracic ipsilateral sidebend, contralateral rotation
Medial intertransversarii cervicis
Medial intertransversarii lumbora	L1-L5 Mammillary process of superior segment	L1-L5 Mammillary process of inferior segment	Spinal nn. (posterior rami)	Bilateral: Cervical extension and stabilization, lumbar extension and stabilization Unilateral: Cervical extension and ipsilateral sidebend, Lumbar extension and ipsilateral sidebend
Multifidus
Posterior intertransversarii cervicis	C2-C7 Posterior tubercle of superior segment	C2-C7 Posterior tubercle of superior segment	Spinal nn. (posterior rami)	Bilateral: Cervical extension and stabilization, lumbar extension and stabilization Unilateral: Cervical extension and ipsilateral sidebend, Lumbar extension and ipsilateral sidebend
Rotatores breves
Rotatores longi
Semispinalis capitis
Semispinalis cervicis
Semispinalis thoracis

Thoracoappendicular

Anterior Axioappendicular

• Pectoralis Major
• Pectoralis Minor
• Subclavius
• Serratus Anterior

Table 14: Anterior Axioappendicular Muscles

Muscle	Origin	Insertion	Innervation	Action
Pectoralis major	Clavicle (medial half) Sternum Costal cartilages 1-6 Rectus sheath (anterior layer)	Humerus (crest of greater tubercle)	Lateral pectoral n. Medial pectoral n. C5 - T1	Entire muscle: Adduction, IR Clavicular & Sternocostal parts: Flexion, Aids in respiration when shoulder is fixed
Pectoralis minor	3-5 ribs	Coracoid process	Medial pectoral n. C8 - T1	Scapula: Depression, Downward rotation, Protraction Respiration: Assists in respiration
Serratus anterior	1-9 Ribs	Superior angle of Scapula (costal and dorsal surfaces) Medial border of scapula (costal surface) Medial border of scapula (costal surface) Inferior angle of Scapula (costal & dorsal surfaces)	Long thoracic n. C5 - C7	Superior part: Lowers raised arm Entire mm.: Protraction, Rib elevation (with fixed shoulder) Inferior part: Rotates scapula laterally forward
Subclavius	1st rib	Clavicle (inferior surface)	N. to subclavius C5 - C6	SCJ: Stabilization

Posterior Axioappendicular

Superficial

• Upper Trapezius
• Middle Trapezius
• Lower Trapezius
• Latissimus Dorsi

Deep

• Levator Scapulae
• Rhomboid Major
• Rhomboid Minor

Table 15: Superficial Posterior Axioappendicular muscles

Muscle	Origin	Insertion	Innervation	Action
Latissimus dorsi	T7-T12 SP Thoracolumbar fascia Inferior angle of scapula 9-12 ribs Posterior third of Iliac crest	Floor of the intertubercular groove of the humerus	Thoracodorsal n. C6 - C8	GHJ: IR, adduction, Extension Respiration: "cough muscle"
Lower trapezius	T5-T12 SP	Scapular spine	Accessory n. (CN XI) C3 - C4	Scapula: Retraction, Depression, Upward rotation, Stabilizes scapula on thorax
Middle trapezius	Aponeurosis of T1-T4 SP	Acromion	Accessory n. (CN XI) C3 - C4	Scapula: Retraction
Upper trapezius	Occiput SP C1-C7	lateral 1/3 of Clavicle	Accessory n. (CN XI) C3 - C4	Scapula: Elevation, Upward rotatino Neck: I/L sidebend, C/L Rotation

Warning: No 'action' link found for variable 'ref-rhomboid-minor' in YAML data.
Warning: No 'action' link found for variable 'ref-rhomboid-minor' in YAML data.
Warning: No 'action' link found for variable 'ref-rhomboid-minor' in YAML data.
Warning: No 'action' link found for variable 'ref-rhomboid-minor' in YAML data.
Warning: No 'action' link found for variable 'ref-rhomboid-minor' in YAML data.
Warning: No 'action' link found for variable 'ref-rhomboid-minor' in YAML data.
Warning: No 'action' link found for variable 'ref-rhomboid-minor' in YAML data.
Warning: No 'action' link found for variable 'ref-rhomboid-minor' in YAML data.
Warning: No 'action' link found for variable 'ref-rhomboid-minor' in YAML data.

Table 16: Deep Posterior Axioappendicular muscles

Muscle	Origin	Insertion	Innervation	Action
Levator scapulae	C1-C4 TP	Superior angle of Scapula	Dorsal scapular n. Cervical spinal nn. C3 - C4	Scapula: Elevation, Downward rotation Cervical: I/L sidebend
Rhomboid major	T1-T4 SP	Medial border of scapula (below scapular spine)	Dorsal scapular n. C4 - C5	Scapula: Retraction assist, Downward rotation, Stabilization
Rhomboid minor	C6 & C7 SP	Medial border of scapula (above scapular spine)	Dorsal scapular n. C4 - C5	Scapula: Retraction assist, Downward rotation, Stabilization

Scapulohumeral (Intrinsic shoulder)

Table 17: Scapulohumeral muscles

Muscle	Origin	Insertion	Innervation	Action
Anterior deltoid	Lateral third of clavicle	Deltoid tuberosity of humerus	Axillary n. C5 - C6	GHJ: Flexion, IR, Adduction
Lateral deltoid	Acromion	Deltoid tuberosity of humerus	Axillary n. C5 - C6	GHJ: Abduction
Posterior deltoid	Scapular spine	Deltoid tuberosity of humerus	Axillary n. C5 - C6	GHJ: Extension, ER, Abduction
Subscapularis	Subscapular fossa	Lesser tubercle of Humerus	Upper Subscapular n. Lower Subscapular n. C5 - C6	GHJ: IR, Stabilization
Supraspinatus	Supraspinous Fossa of scapula	Greater tubercle of Humerus	Suprascapular n. C4 - C6	GHJ: Initiates abduction, Stabilization
Teres major	Inferior angle of Scapula	Crest of lesser tubercle of humerus	Thoracodorsal n. C5 - C6	GHJ: IR, Adduction, Extension
Teres minor		Greater tubercle of Humerus	Axillary n. C5 - C6	GHJ: ER, Weak adduction

Arm

Anterior Arm

• Biceps Brachii (Long head)
• Biceps Brachii (Short head)
• Brachialis
• Coracobrachialis

Table 18: Anterior arm muscles

Muscle	Origin	Insertion	Innervation	Action
Biceps brachii Long head	Supraglenoid tubercle of scapula Adjacent rim of Glenoid Labrum	Radial tuberosity Bicipital aponeurosis	Musculocutaneous n. C5 - C6	Elbow: Flexion, Supination GHJ: Flexion, Stabilization of humeral head during deltoid contraction, Abduction, IR
Biceps brachii Short head	Coracoid process	Radial tuberosity Bicipital aponeurosis	Musculocutaneous n. C5 - C6	Elbow: Flexion, Supination GHJ: Flexion, Stabilization of humeral head during deltoid contraction, Abduction, IR
Brachialis	Distal half of anterior Humerus	Ulnar tuberosity	Musculocutaneous n. Radial n. C5 - C7	Elbow: Flexion
Coracobrachialis	Coracoid process	Humerus (in line with crest of lesser tubercle)	Musculocutaneous n. C5 - C7	GHJ: Flexion, Adduction, IR

Posterior Arm

• Triceps brachii (Long head)
• Triceps brachii (Medial head)
• Triceps brachii (Lateral head)
• Anconeus

Table 19: Posterior arm muscles

Muscle	Origin	Insertion	Innervation	Action
Anconeus	GHJ joint capsule	Olecranon of Ulna (radial surface)	Radial n. C6 - C8	Elbow: Extension, Tightens joint
Triceps brachii lateral head	Posterior humerus just *proximal* to radial groove Lateral intermuscular septum	Olecranon of Ulna	Radial n. C6 - C8	Elbow: Extension
Triceps brachii Long head	Infraglenoid tubercle of Scapula	Olecranon of Ulna	Radial n. C6 - C8	Elbow: Extension GHJ: Extension, Adduction
Triceps brachii medial head	Posterior humerus just distal to radial groove Medial intermuscular septum	Olecranon of Ulna	Radial n. C6 - C8	Elbow: Extension

Forearm

Anterior Forearm

Table 20: Anterior forearm muscles

Muscle	Origin	Insertion	Innervation	Action
Brachioradialis	Lateral distal humerus Lateral intermuscular septum	Styloid process of Radius	Radial n. C5 - C6	Elbow: Flexion, Semipronation (to 90°)
Flexor carpi radialis	Medial epicondyle	Base of 2nd Metacarpal (Sometimes base of 3rd Met)	Median n. C6 - C7	Wrist: Flexion, Radial deviation
Flexor carpi ulnaris	Medial epicondyle Olecranon	Hook of Hamate Base of 5th metacarpal	Ulnar n. C7 - T1	Wrist: Flexion, Ulnar deviation
Flexor digitorum profundus	Proximal 2/3 of Ulna Interosseous_membrane	Palmar surface of Distal phalanges 2-5	Median n. (digits 2-3) Ulnar n. (digits 4-5) C8 - T1	Wrist: Flexion MCP, PIP, & DIP 2-5: Flexion
Flexor digitorum superficialis	Medial epicondyle Coronoid process Anterior proximal half of Radius	Sides of middle phalanges 2-5	Median n. C8 - T1	Elbow: Weak flexion Wrist: Flexion 2-5 MCP & PIP: Flexion, Flexion
Flexor pollicis longus	Midanterior Radius Adjacent Interosseous membrane	Distal phalanx of thumb	Median n. C8 - T1	Wrist: Flexion, Radial deviation 1st CMC, IP, MCP: Flexion
Palmaris longus	Medial epicondyle	Palmar aponeurosis	Median n. C6 - C7	Elbow: Weak flexion Wrist: Tightens aponeurosis
Pronator quadratus	Distal 1/4 of anterior Ulna	Distal 1/4 of anterior Radius	Median n. C8 - T1	Elbow/Forearm: Pronation Distal RUJ: Stabilization
Pronator teres	Medial epicondyle Coronoid process	L:ateral radius distal to supinator	Median n. C6 - C7	Elbow: Weak flexion, Pronation

Posterior Forearm

Table 21: Posterior forearm muscles

Muscle	Origin	Insertion	Innervation	Action
Abductor pollicis longus	Dorsal Radius Dorsal Ulna IO membrane	1st metacarpal base	Radial n. C7 - C8	Radiocarpal joint: Radial dev. CMC & 1st MCP: Abduction
Extensor carpi radialis brevis	Lateral epicondyle of Humerus	3rd metacarpal base	Radial n. C7 - C8	Elbow: Weak flexion Wrist: Extension, Radial deviation
Extensor carpi radialis longus	Lateral supracondylar ridge Lateral intermuscular septum	2nd metacarpal base	Radial n. C6 - C7	Elbow: Weak flexion Wrist: Extension, Radial deviation
Extensor carpi ulnaris	Lateral epicondyle of Humerus Ulnar head	5th metacarpal base	Radial n. C7 - C8	Wrist: Extension, Ulnar deviation
Extensory digiti minimi	Lateral epicondyle of Humerus	5th Dorsal digital expansion	Radial n. C7 - C8	Wrist: Extension, Ulnar deviation 5th MCP, PIP, DIP: Extension, Abduction
Extensor digitorum	Lateral epicondyle of Humerus	2-5th Dorsal digital expansion	Radial n. C7 - C8	Wrist: Extension 2-5 MCP, PIP, DIP: Extension
Extensor indicis	Posterior Ulna IO membrane	2nd Dorsal digital expansion	Radial n. C7 - C8	Wrist: Extension 2nd MCP, PIP, DIP: Extension
Extensor pollicis brevis	Radius (posterior) IO membrane	Base of 1st proximal phalanx	Radial n. C7 - C8	Radiocarpal joint: Radial dev. 1st CMC & MCP: Extension
Extensor pollicis longus	Dorsal ulna IO membrane	Base of 1st Distal phalanx	Radial n. C7 - C8	Wrist: Extension, Radial dev. CMC: Abduction 1st MCP & IP: Extension
Supinator	Olecranon Lateral epicondyle Radial collateral lig. Annular lig.	Radius (between radial tuberosity and pronator teres)	Radial n. C6 - C7	Radioulnar joints: Supination

Hand

Thenar Muscles

• Opponens Pollicis
• Abductor Pollicis Brevis
• Flexor Pollicis Brevis

Table 22: Thenar muscles

Muscle	Origin	Insertion	Innervation	Action
Abductor pollicis brevis	Scaphoid Trapezium Flexor retinaculum	1st proximal phalanx via radial sesamoid	Median n. C8 - T1	CMC: Abduction
Flexor pollicis brevis	Flexor retinaculum Capitate Trapezium	1st proximal phalanx via radial sesamoid	Median n. Ulnar n. C8 - T1	CMC: Flexion
Opponens pollicis	Trapezium	1st metacarpal (radial border)	Median n. C8 - T1	CMC: Opposition

Adductor Compartment

• Adductor Pollicis

Table 23: Adductor Compartment of the Hand

Muscle	Origin	Insertion	Innervation	Action
Adductor pollicis	3rd MCP (plantar surface) Capitate 2-3rd metacarpal base	Base of 1st proximal phalanx (ulnar sesamoid)	Ulnar n. C8 - T1	CMC: Adduction 1st MCP: Flexion

Hypothenar

• Abductor Digiti Minimi (hand)
• Flexor Digiti Minimi Brevis (Hand)
• Opponens Digiti Minimi

Table 24: Hypothenar muscles of the Hand

Muscle	Origin	Insertion	Innervation	Action
Abductor digiti minimi (hand)	hand_flexor_retinaculum	Base of 1st proximal phalanx (radial sesamoid)	Median n. C8 - T1	CMC: Abduction
Flexor digiti minimi brevis (hand)	Hook of Hamate hand_flexor_retinaculum	Base of 5th Proximal Phalanx	Ulnar n. C8 - T1	5th MCP: Flexion
Opponens digiti minimi (hand)	Hook of Hamate hand_flexor_retinaculum	5th Proximal Phalanx (ulnar border)	Ulnar n. C8 - T1	5th MCP: Opposition

Short Muscles

Warning: No 'path' link found for variable 'ref-1st-hand-lumbrical' in YAML data.
Warning: No 'path' link found for variable 'ref-2nd-hand-lumbrical' in YAML data.
Warning: No 'path' link found for variable 'ref-3rd-hand-lumbrical' in YAML data.
Warning: No 'path' link found for variable 'ref-4th-hand-lumbrical' in YAML data.
Warning: No 'origin' link found for variable 'ref-1st-hand-lumbrical' in YAML data.
Warning: No 'origin' link found for variable 'ref-1st-hand-lumbrical' in YAML data.
Warning: No 'origin' link found for variable 'ref-2nd-hand-lumbrical' in YAML data.
Warning: No 'origin' link found for variable 'ref-2nd-hand-lumbrical' in YAML data.
Warning: No 'origin' link found for variable 'ref-3rd-hand-lumbrical' in YAML data.
Warning: No 'origin' link found for variable 'ref-3rd-hand-lumbrical' in YAML data.
Warning: No 'origin' link found for variable 'ref-4th-hand-lumbrical' in YAML data.
Warning: No 'origin' link found for variable 'ref-4th-hand-lumbrical' in YAML data.
Warning: No 'insertion' link found for variable 'ref-1st-hand-lumbrical' in YAML data.
Warning: No 'insertion' link found for variable 'ref-1st-hand-lumbrical' in YAML data.
Warning: No 'insertion' link found for variable 'ref-2nd-hand-lumbrical' in YAML data.
Warning: No 'insertion' link found for variable 'ref-2nd-hand-lumbrical' in YAML data.
Warning: No 'insertion' link found for variable 'ref-3rd-hand-lumbrical' in YAML data.
Warning: No 'insertion' link found for variable 'ref-3rd-hand-lumbrical' in YAML data.
Warning: No 'insertion' link found for variable 'ref-4th-hand-lumbrical' in YAML data.
Warning: No 'insertion' link found for variable 'ref-4th-hand-lumbrical' in YAML data.
Warning: No 'innervation' link found for variable 'ref-1st-hand-lumbrical' in YAML data.
Warning: No 'innervation' link found for variable 'ref-1st-hand-lumbrical' in YAML data.
Warning: No 'innervation' link found for variable 'ref-2nd-hand-lumbrical' in YAML data.
Warning: No 'innervation' link found for variable 'ref-2nd-hand-lumbrical' in YAML data.
Warning: No 'innervation' link found for variable 'ref-3rd-hand-lumbrical' in YAML data.
Warning: No 'innervation' link found for variable 'ref-3rd-hand-lumbrical' in YAML data.
Warning: No 'innervation' link found for variable 'ref-4th-hand-lumbrical' in YAML data.
Warning: No 'innervation' link found for variable 'ref-4th-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-1st-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-1st-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-1st-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-1st-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-2nd-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-2nd-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-2nd-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-2nd-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-3rd-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-3rd-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-3rd-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-3rd-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-4th-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-4th-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-4th-hand-lumbrical' in YAML data.
Warning: No 'action' link found for variable 'ref-4th-hand-lumbrical' in YAML data.

Table 25: Short muscles of the Hand

Muscle	Origin	Insertion	Innervation	Action
1st Dorsal interossei (hand)	1-2nd MCP adjacent sides	2nd dorsal digital expansion 2nd Proximal Phalanx (radial border)	Ulnar n. C8 - T1	2nd digit: MCP Flexion, PIP & DIP Extension & Abduction
1st Lumbrical (hand)	Tendon of flexor digitorum profundus	2nd dorsal digital expansion	Median n. C8 - T1	2nd digit: MCP Flexion, PIP & DIP Extension
1st Palmar interossei (hand)	2nd MCP (ulnar side)	2nd dorsal digital expansion 2nd Proximal Phalanx (radial border)	Ulnar n. C8 - T1	2nd digit: MCP Flexion, PIP & DIP Extension & Adduction
2nd Dorsal interossei (hand)	2-3rd MCP adjacent sides	3rd dorsal digital expansion 3rd Proximal Phalanx (radial border)	Ulnar n. C8 - T1	3rd digit: MCP Flexion, PIP & DIP Extension & Abduction
2nd Lumbrical (hand)	Tendon of flexor digitorum profundus	3rd dorsal digital expansion	Median n. C8 - T1	3rd digit: MCP Flexion, PIP & DIP Extension
2nd Palmar interossei (hand)	4th MCP (radial side)	4th dorsal digital expansion 4th Proximal Phalanx (radial border)	Ulnar n. C8 - T1	4th digit: MCP Flexion, PIP & DIP Extension & Adduction
3rd Dorsal interossei (hand)	3-4th MCP adjacent sides	4th dorsal digital expansion 4th Proximal Phalanx (radial border)	Ulnar n. C8 - T1	4th digit: MCP Flexion, PIP & DIP Extension & Abduction
3rd Lumbrical (hand)	Tendon of flexor digitorum profundus	4th dorsal digital expansion	Median n. C8 - T1	4th digit: MCP Flexion, PIP & DIP Extension
3rd Palmar interossei (hand)	5th MCP (radial side)	5th dorsal digital expansion 5th Proximal Phalanx (radial border)	Ulnar n. C8 - T1	5th digit: MCP Flexion, PIP & DIP Extension & Adduction
4th Dorsal interossei (hand)	4-5th MCP adjacent sides	5th dorsal digital expansion 5th Proximal Phalanx (radial border)	Ulnar n. C8 - T1	5th digit: MCP Flexion, PIP & DIP Extension & Abduction
4th Lumbrical (hand)	Tendon of flexor digitorum profundus	5th dorsal digital expansion	Median n. C8 - T1	5th digit: MCP Flexion, PIP & DIP Extension

Hip & Thigh

Iliopsoas

Table 26: Iliopsoas Muscles

Muscle	Origin	Insertion	Innervation	Action
Iliacus	Iliac Fossa	Lesser Trochanter	Femoral n. L2 - L3	Hip: Flexion, ER L/S (UNIL contraction on fixed femur): I/L spine sidebend L/S (BIL contraction): Raises trunk from supine position
Psoas Major	T12-L4 and associated IV discs L1-L5 TP	Lesser Trochanter	Lumbar Plexus Direct Br. L1 - L3	Hip: Flexion, ER L/S (unilateral contraction with femur fixed): I/L spine sidebend L/S (bilateral contraction): Raises trunk from supine position
Psoas Minor	T12, L1 vertebrae (lateral aspect) and IVD	Pectineal Line Iliopubic ramus Iliac fascia Inguinal ligament	Spinal nn. L1 - L3	Trunk: Weak flexion

Gluteal

Table 27: Gluteal muscles

Muscle	Origin	Insertion	Innervation	Action
Gluteus Maximus	Sacrum (dorsal surface, lateral part) Ilium (gluteal surface, posterior part) Thoracolumbar fascia sacrotuberous lig.	IT Band Gluteal tuberosity	Inferior gluteal n. L5 - S2	Entire mm.: Extension, ER (when <60° HF) Upper fibers: Abduction, IR (when &gt60° HF) Lower fibers: Adduction
Gluteus medius	Ilium	Greater trochanter (lateral surface)	Superior gluteal n. L4 - S1	Entire mm.: Abduction, Frontal stabilization Anterior fibers: Flexion, IR Posterior fibers: Extension, ER (when <60° HF), IR (when &gt60° HF)
Gluteus Minimus	Ilium gluteal surface (inferior to gluteus medius origin)	Greater trochanter (anterolateral surface)	Superior gluteal n. L4 - S1	Entire mm.: Abduction, Frontal stabilization Anterior fibers: Flexion, IR Posterior fibers: Extension, ER (when <60° HF), IR (when &gt60° HF)
Inferior Gemellus	Ischial tuberosity	Medial surface of greater trochanter via obturator internus tendon	Nerve to Quadratus femoris L5 - S1	Hip: ER, Extension, Abduction
Obturator Internus	Obturator membrane and its bony boundaries	Medial surface of Greater Trochanter	Nerve to Obturator internus L5 - S1	Hip: ER, Extension, Abduction, Stabilization
Piriformis	Anterior Sacrum	Apex of the Greater Trochanter	Sacral Plexus Direct Br. S1 - S2	Hip (at <60° flexion): ER Hip: Abduction, Extension, Stabilization Hip (at ≥60° flexion): IR
Quadratus femoris	Lateral border of Ischial tuberosity	Intertrochanteric crest	Nerve to Quadratus femoris L5 - S1	Hip: ER
Superior gemellus	Ischial spine	Medial surface of greater trochanter via obturator internus tendon	Nerve to Obturator internus L5 - S1	Hip: ER, Extension, Abduction
Tensor Fascia Latae	ASIS	IT Band	Superior gluteal n. L4 - S1	Tenses fascia latae Hip: Abduction, Flexion, IR Flexed knee: ER Extended knee: Locks out extension

Medial Thigh

Table 28: Medial thigh muscles

Muscle	Origin	Insertion	Innervation	Action
Adductor brevis	Inferior pubic ramus	Linea aspera	Obturator n. L2 - L3	Hip: Adduction, Flexion, Extension Pelvis: Frontal stabilization, Sagittal stabilization
Adductor Longus	Superior pubis ramus Anterior side of Pubic Symphysis	Linea aspera	Obturator n. L2 - L4	Hip: Adduction, Flexion, Extension Pelvis: Frontal plane stabilization, Sagittal plane stabilization
Adductor Magnus	Inferior pubic ramus Ischial ramus Ischial tuberosity	Medial lip of Linea aspera Adductor tubercle	Obturator n. Tibial n. L2 - L4	Hip: Adduction, Flexion, Extension, IR Pelvis: Frontal stabilization, Sagittal stabilization
Gracilis	Inferior pubic ramus	Pes anserine	Obturator n. L2 - L3	Hip: Adduction, Flexion Knee: Flexion, IR
Obturator externus	Outer surface of Obturator membrane Adjacent bony boundaries	Trochanteric Fossa	Obturator n. L3 - L4	Hip: Adduction, ER Pelvis: Sagittal Stabilization
Pectineus	Pecten pubis	Pectineal line Proximal linea aspera	Femoral n. Obturator n. L2 - L3	Hip: ER, Adduction, *slight* Flexion Pelvis: Frontal plane stabilization, Sagittal plane stabilization

Anterior Thigh

Table 29: Anterior thigh muscles

Muscle	Origin	Insertion	Innervation	Action
Articular genus	Anterior Femoral shaft	Suprapatellar recess of knee joint capsule	Femoral n. L2 - L4	Knee: Extension Knee Jt. Capsule: Retraction of the suprapatellar bursa to prevent entrapment
Rectus femoris	AIIS Acetabular roof	Tibial tuberosity via Patellar ligament	Femoral n. L2 - L4	Hip: Flexion Knee: Extension
Sartorius	ASIS	Pes anserine	Femoral n. L2 - L3	Hip: Flexion, ER, Abduction Knee: Flexion, IR
Vastus intermedius	Anterior Femoral shaft	Tibial tuberosity via Patellar ligament	Femoral n. L2 - L4	Knee: Extension
Vastus lateralis	Lateral lip of Linea aspera Lateral surface of Greater trochanter	Tibial tuberosity via Patellar ligament Tibial tuberosity and patella via Patellar retinacula	Femoral n. L2 - L4	Knee: Extension
Vastus medialis	Linea aspera Intertrochanteric line	Tibial tuberosity via Patellar ligament Patellar retinacula	Femoral n. L2 - L4	Knee: Extension

Posterior Thigh

Table 30: Posterior thigh muscles

Muscle	Origin	Insertion	Innervation	Action
Biceps femoris long head	Ischial tuberosity Sacrotuberous lig. (Common head with semitendinosus)	Fibular head	Tibial n. L5 - S2	Hip: Extension Knee: Flexion, ER Pelvis: Sagittal stabilization
Biceps femoris short head	Lateral lip of Linea aspera	Fibular head	Common Fibular n. L5 - S2	Knee: Flexion, ER
Semimembranosus	Ischial tuberosity	Medial tibial condyle Oblique popliteal lig. Popliteus fascia	Tibial n. L5 - S2	Hip: Extension Knee: Flexion, IR Pelvis: Sagittal stabilization
Semitendinosus	Ischial tuberosity Sacrotuberous lig. (common head with biceps femoris long head)	Pes anserine	Tibial n. L5 - S2	Hip: Extension Knee: Flexion, IR Pelvis: Sagittal stabilization

Knee & Lower Leg

Anterior Compartment

Table 31: Anterior lower leg muscles

Muscle	Origin	Insertion	Innervation	Action
Extensor digitorum longus	Lateral condyle of Tibia Fibular head and medial surface IO membrane	Dorsal aponeurosis of 2-5th distal phalanges	Deep Fibular n. L4 - L5	TCJ: DF STJ: INV or EV (position dependent) 2nd-5th Toe: MTP Extension, PIP Extension, DIP Extension
Extensor Hallucis Longus	Fibula (middle 1/3 of medial surface) IO membrane	Dorsal aponeurosis of 1st distal phalanx	Deep Fibular n. L4 - L5	TCJ: DF STJ: Inversion 1st Toe: MTP Extension, IP Extension
Fibularis tertius	Anterior border of Distal Fibula	Shaft or Base of 5th MT	Deep Fibular n. L4 - L5	TCJ: DF STJ: Eversion
Tibialis Anterior	Tibia (Upper 2/3 of lateral surface) IO membrane Superficial crural fascia	Medial cuneiform (Medial & plantar surface) 1st Metatarsal (medial base)	Deep Fibular n. L4 - L5	TCJ: DF STJ: Inversion

Lateral Compartment

Table 32: Lateral lower leg muscles

Muscle	Origin	Insertion	Innervation	Action
Fibularis brevis	Middle lateral surface of Fibula	Base of 5th MT	Superficial Fibular n. L5 - S1	TCJ: PF STJ: Eversion
Fibularis longus	Proximal lateral surface of Fibula	Medial cuneiform Base of 1st MT	Superficial Fibular n. L5 - S1	TCJ: PF STJ: Eversion Arch: Transverse arch support

Posterior Compartment

Table 33: Posterior lower leg muscles

Muscle	Origin	Insertion	Innervation	Action
Flexor digitorum longus	Middle 1/3 of posterior surface of Tibia	Bases of 2-5 Distal Phalanges	Tibial n. L5 - S2	TCJ: PF STJ: Inversion 2nd-5th Toe: MTP Flexion, PIP Flexion, DIP Flexion
Flexor hallucis longus	Posterior distal 2/3 of Fibula IO membrane	Base of 1st Distal Phalanx	Tibial n. L5 - S2	TCJ: PF STJ: Inversion 1st Toe: MTP Flexion, IP Flexion
Gastrocnemius	Superior-posterior aspect of Medial Femoral Condyle Lateral surface of Lateral Femoral Condyle	Calcaneal tuberosity via Achilles' Tendon	Tibial n. S1 - S2	TCJ: PF Knee: Flexion
Plantaris	Lateral epicondyle of Femur	Calcaneal tuberosity	Tibial n. S1 - S2	Knee: *negligble* Flexion TCJ: PF Proprioception: Organ of proprioception for the plantarflexors
Popliteus	Lateral Femoral Condyle Posterior horn of Lateral Meniscus	Posterior surface of Tibia	Tibial n. L4 - S1	Knee: Flexion, Unlocks the knee via knee IR
Soleus	Posterior Fibula Posterior Tibia	Calcaneal tuberosity via Achilles' Tendon	Tibial n. S1 - S2	TCJ: PF Lower leg: Stabilization
Tibialis posterior	IO membrane Adjacent Tibia Adjacent Fibula	Cuneiforms 2-4 MT bases	Tibial n. L4 - L5	TCJ: PF Arch support: Transverse arch, Longitudinal arch

Foot

Dorsum of the Foot

Table 34: Dorsum muscles of the Foot

Muscle	Origin	Insertion	Innervation	Action
Extensor digitorum brevis	Calcaneus (lateral dorsal)	Bases of middle phalanx 2-4	Deep Fibular n. L5 - S1	2nd-4th Toe: MTP Extension, PIP Extension
Extensor hallucis brevis	Calcaneus (lateral dorsal)	1st Proximal phalanx	Deep Fibular n. L5 - S1	1st Toe: MTP Extension

Superficial Intrinsic Plantar Foot muscles

Table 35: Superficial Plantar Foot Intrinsic muscles

Muscle	Origin	Insertion	Innervation	Action
Abductor hallucis	Medial calcaneal tuberosity Plantar aponeurosis Flexor retinaculum	Medial aspect of 1st Proximal phalanx	Medial Plantar n. S1 - S2	1st Toe: MTP Flexion, MTP Abduction Arch support: Longitudinal arch support
Abductor digiti minimi	Medial tubercle of calcaneal tuberosity Cuboid Lateral cuneiforms 3-5th MTP joints Deep transverse metatarsal lig.	Base of 5th proximal phalanx Base of 1st proximal phalanx (via common tendon)	Lateral Plantar n. Lateral Plantar n. (Deep branch) S1 - S3	5th Toe: MTP Flexion 1st MTP: Flexion, Adduction Arch Support: *Transverse head* supports transverse arch, *Oblique head* supports longitudinal arch
Flexor digitorum brevis	Medial tubercle of calcaneal tuberosity Plantar aponeurosis	Sides of middle phalanx 2-5	Medial Plantar n. S1 - S2	2nd-5th Toe: MTP Flexion, PIP Flexion Arch support: Longitudinal arch support

Deep Intrinsic plantar foot muscles

Table 36: Deep Plantar Foot Intrinsic muscles

Muscle	Origin	Insertion	Innervation	Action
Abductor digiti minimi	Medial tubercle of calcaneal tuberosity Cuboid Lateral cuneiforms 3-5th MTP joints Deep transverse metatarsal lig.	Base of 5th proximal phalanx Base of 1st proximal phalanx (via common tendon)	Lateral Plantar n. Lateral Plantar n. (Deep branch) S1 - S3	5th Toe: MTP Flexion 1st MTP: Flexion, Adduction Arch Support: *Transverse head* supports transverse arch, *Oblique head* supports longitudinal arch
Dorsal interossei (4 muscles)	1-5 metatarsals (two heads on opposing sides)	Medial aspect of 2nd proximal phalanx base Lateral aspect of 2nd-4th proximal phalanx bases 2-4 Toes at Dorsal aponeurosis	Lateral plantar n. S2 - S3	2nd-4th Toes: MTP Flexion, MTP 3-4 abduction, PIP Extension, DIP Extension
Flexor digiti minimi brevis (foot)	Base of 5th Metatarsal Long plantar lig.	Base of 5th proximal phalanx	Lateral Plantar n. (superficial branch) S2 - S3	5th MTP Flexion
Flexor hallucis brevis	Cuboid Lateral cuneiforms Plantar calcaneocuboid lig.	Medial Sesamoid bone Lateral Sesamoid bone	Lateral Plantar n. Medial Plantar n. S1 - S2	MTP Flexion Supports Longitudinal Arch
Lumbricals (Foot)	FDL tendons (medial borders)	2-5th toes at dorsal aponeurosis	Medial Plantar n. Lateral Plantar n. S2 - S3	2nd-5th Toes: MTP Flexion, PIP Extension, DIP Extension
Opponens digiti minimi	Long plantar lig. *Fibularis longus* plantar tendon sheath	5th metatarsal	Lateral Plantar n. (superficial branch) S2 - S3	Pulls 5th metatarsal in plantar and medial direction
Plantar interossei (3 muscles)	Medial border of 3rd-5th metatarsals	Medial aspect of 3rd-5th proximal phalanx	Lateral plantar n. S2 - S3	3rd-5th Toes: MTP Flexion, MTP Adduction, PIP Extension, DIP Extension
Quadratus plantae	Calcaneal tuberosity (medial and plantar borders)	Tendons of FDL (lateral borders)	Lateral Plantar n. S1 - S3	Redirects and augments pull of the FDL

References

1.

Betts JG, Blaker W. Openstax Anatomy and Physiology. 2nd ed. OpenStax; 2022. https://openstax.org/details/books/anatomy-and-physiology-2e/?Book%20details