Category: Muscles

Download these notes.

Anatomy & Physiology: Muscles—Erector Spinae Group.

Structure.

• Origin: pelvis.
• Insertion: spine, rib cage, and head.

Function.

• Concentric action: trunk, neck, and head extension at the spinal joints; lateral flexion of the trunk, neck, and head at the spinal joints. Lesser: ipsilateral rotation of the trunk, neck, and head at spinal joints.
• Reverse mover action: pelvic anterior tilt at lumbosacral joint; lower spine extension relative to upper spine. Lesser: ipsilateral elevation of pelvis at LS joint; lateral flexion of lower spine relative to upper spine; contralateral rotation of pelvis and lower spine.
• Eccentric action: spinal flexion, rotation, and lateral flexion.
• Isometric action: stabilization of the spine.
• Innervation: cervical and thoracic spinal nerves.
• Arterial supply: dorsal branches of posterior intercostal and lumbar arteries; thoracodorsal artery.

Clinical Significance.

Erector spinae group. Used with permission by 3D4Medical.

References

Biel, A. (2015). Trail guide to the body: A hands-on guide to locating muscles, bones and more.

Cedars-Sinai. (2018). Vertebrae of the spine. Retrieved from https://www.cedars-sinai.org/health-library/diseases-and-conditions/v/vertebrae-of-the-spine.html

Clark, M., Lucett, S., Sutton, B. G., & National Academy of Sports Medicine. (2014). NASM essentials of corrective exercise training. Burlington, MA: Jones & Bartlett Learning.

Jenkins, G., & Tortora, G. J. (2012). Anatomy and Physiology: From Science to Life, 3rd Edition International Stu. John Wiley & Sons.

Muscolino, J. E. (2017). The muscular system manual: The skeletal muscles of the human body.

Download these notes.

Anatomy & Physiology: Muscles—Palmaris Brevis.

Structure.

• Origin: flexor retinaculum and palmar aponeurosis.
• Insertion: Skin of palm into dermis.

Function.

• Concentric action: wrinkles the skin of the palm.
• Reverse mover action: wrinkles the skin of the palm.
• Eccentric action: controls/restrains/slows stretching of the skin of the palm.
• Isometric action: little to no stabilization functions.
• Innervation: ulnar nerve.
• Arterial supply: ulnar artery.

Clinical Significance.

Palmaris brevis. Used with permission by 3D4Medical.

References

Biel, A. (2015). Trail guide to the body: A hands-on guide to locating muscles, bones and more.

Cedars-Sinai. (2018). Vertebrae of the spine. Retrieved from https://www.cedars-sinai.org/health-library/diseases-and-conditions/v/vertebrae-of-the-spine.html

Clark, M., Lucett, S., Sutton, B. G., & National Academy of Sports Medicine. (2014). NASM essentials of corrective exercise training. Burlington, MA: Jones & Bartlett Learning.

Jenkins, G., & Tortora, G. J. (2012). Anatomy and Physiology: From Science to Life, 3rd Edition International Stu. John Wiley & Sons.

Muscolino, J. E. (2017). The muscular system manual: The skeletal muscles of the human body.

Download these notes.

Anatomy & Physiology: Muscles—Dorsal Interossei.

Structure.

• Origin: adjacent sides of metacarpals.
• Insertion: proximal phalanx of each finger.

Function.

• Concentric action: abduct fingers 2-4 at metacarpophalangeal joints; flex fingers 2-4 at metacarpophalangeal joints; and extends fingers at interphalangeal joints.
• Reverse mover action: abduct metacarpals of fingers 2-4; flex and adduct thumb at CMC; flex metacarpals of fingers 2-4 at MCP; extend proximal phalanges of fingers 2-4 at PIP and DIP.
• Eccentric action: controls/restrains/slows adduction, flexion and extension of fingers 2-4 at MCP.
• Isometric action: stabilize CMC of thumb, and MCP and IP for fingers 2-4.
• Innervation: ulnar nerve.
• Arterial supply: branches of radial and ulnar arteries.

Clinical Significance.

More.

• https://www.anatomynext.com/dorsal-interossei-of-hand/
• https://www.kenhub.com/en/library/anatomy/dorsal-interossei-muscles-of-the-hand

Dorsal interossei manus. Used with permission by 3D4Medical.

References

Biel, A. (2015). Trail guide to the body: A hands-on guide to locating muscles, bones and more.

Cedars-Sinai. (2018). Vertebrae of the spine. Retrieved from https://www.cedars-sinai.org/health-library/diseases-and-conditions/v/vertebrae-of-the-spine.html

Clark, M., Lucett, S., Sutton, B. G., & National Academy of Sports Medicine. (2014). NASM essentials of corrective exercise training. Burlington, MA: Jones & Bartlett Learning.

Jenkins, G., & Tortora, G. J. (2012). Anatomy and Physiology: From Science to Life, 3rd Edition International Stu. John Wiley & Sons.

Muscolino, J. E. (2017). The muscular system manual: The skeletal muscles of the human body.

Download these notes.

Anatomy & Physiology: Muscles—Palmar Interossei.

Structure.

• Origin: sides of shafts of metacarpals of all fingers (except middle finger).
• Insertion: sides of bases of proximal phalanges of all fingers (except middle finger).

Function.

• Concentric action: adduct fingers at metacarpophalangeal joints; flex fingers at metacarpophalangeal joints. Lesser: flexion and extension of fingers 2, 4, and 5 at MCP, and PIP and DIP respectively.
• Reverse mover action: flex and adduct metacarpals of fingers 2, 4, and 5 at MCP; extend proximal phalanges of fingers 2, 4, and 5 at PIP and DIP.
• Eccentric action: controls/restrains/slows abduction and extension of fingers 2, 4, and 5 at MCP; and flexion of fingers 2, 4, and 5 at PIP and DIP.
• Isometric action: stabilizes MCP, PIP, and DIP of fingers 2, 4, and 5.
• Innervation: ulnar nerve.
• Arterial supply: branches of radial and ulnar arteries.

Clinical Significance.

More.

• https://www.anatomynext.com/palmar-interossei/
• https://www.youtube.com/watch?v=HtqZmJe5HtQ
• https://www.youtube.com/watch?v=FXHHuhEpjJY

Palmar interossei. Used with permission by 3D4Medical.

References

Biel, A. (2015). Trail guide to the body: A hands-on guide to locating muscles, bones and more.

Cedars-Sinai. (2018). Vertebrae of the spine. Retrieved from https://www.cedars-sinai.org/health-library/diseases-and-conditions/v/vertebrae-of-the-spine.html

Clark, M., Lucett, S., Sutton, B. G., & National Academy of Sports Medicine. (2014). NASM essentials of corrective exercise training. Burlington, MA: Jones & Bartlett Learning.

Jenkins, G., & Tortora, G. J. (2012). Anatomy and Physiology: From Science to Life, 3rd Edition International Stu. John Wiley & Sons.

Muscolino, J. E. (2017). The muscular system manual: The skeletal muscles of the human body.

Download these notes.

Anatomy & Physiology: Muscles—Lumbricals.

Structure.

• Origin: lateral sides of tendons and flexor digitorum profundus of each finger.
• Insertion: lateral sides of tendons of extensor digitorum on proximal phalanges of each finger.

Function.

• Concentric action: flexes each finger at metacarpophalangeal joints and extends fingers at interphalangeal joints. Lesser: abduct and adduct fingers II-V at MCP joints.
• Reverse mover action: extend proximal phalanges at PIP and DIP; flex metacarpals at MCP; abduct/adduct metacarpals at MCP.
• Eccentric action: controls/restrains/slows flexion, extension, adduction/abduction of fingers II-V at MCP.
• Isometric action: stabilizes MCP and interphalangeal joints of fingers II-V.
• Innervation: median and ulnar nerves.
• Arterial supply: branches of radial and ulnar arteries.

Clinical Significance.

More.

• https://www.anatomynext.com/lumbricals-of-hand/
• https://www.youtube.com/watch?v=vvm4fkNkiDM
• https://www.youtube.com/watch?v=H_481JVpc5U
• https://www.youtube.com/watch?v=7a2A2Elt3cE

Lumbricals manus. Used with permission by 3D4Medical.

References

Biel, A. (2015). Trail guide to the body: A hands-on guide to locating muscles, bones and more.

Cedars-Sinai. (2018). Vertebrae of the spine. Retrieved from https://www.cedars-sinai.org/health-library/diseases-and-conditions/v/vertebrae-of-the-spine.html

Clark, M., Lucett, S., Sutton, B. G., & National Academy of Sports Medicine. (2014). NASM essentials of corrective exercise training. Burlington, MA: Jones & Bartlett Learning.

Jenkins, G., & Tortora, G. J. (2012). Anatomy and Physiology: From Science to Life, 3rd Edition International Stu. John Wiley & Sons.

Muscolino, J. E. (2017). The muscular system manual: The skeletal muscles of the human body.

Download these notes.

Anatomy & Physiology: Muscles—Adductor Pollicis.

Structure.

• Origin: oblique head—capitate and metacarpals II and III; transverse head—metacarpal III.
• Insertion: medial side of proximal phalanx of thumb by a tendon containing a sesamoid bone.

Function.

• Concentric action: adducts thumb at carpometacarpal and metacarpophalangeal joints. Lesser: flexion and extension of thumb at MCP and IP joints respectively.
• Reverse mover action: adducts, flexes trapezium at CMC; flex and extend metacarpal of thumb at MCP and IP respectively.
• Eccentric action: controls/restrains/slows thumb abduction at CMC, extension of thumb at CMC and MCP; flexion at IP of thumb.
• Isometric action: stabilizes CMC, MCP, and IP of thumb.
• Innervation: ulnar nerves.
• Arterial supply: branches of radial artery.

Clinical Significance.

More.

• https://www.anatomynext.com/adductor-pollicis/
• https://www.youtube.com/watch?v=A7FFIz99laY
• https://www.youtube.com/watch?v=4hjIcK4CQmI
• https://www.youtube.com/watch?v=q71qwvqDBCY

Adductor pollicis. Used with permission by 3D4Medical.

References

Biel, A. (2015). Trail guide to the body: A hands-on guide to locating muscles, bones and more.

Cedars-Sinai. (2018). Vertebrae of the spine. Retrieved from https://www.cedars-sinai.org/health-library/diseases-and-conditions/v/vertebrae-of-the-spine.html

Clark, M., Lucett, S., Sutton, B. G., & National Academy of Sports Medicine. (2014). NASM essentials of corrective exercise training. Burlington, MA: Jones & Bartlett Learning.

Jenkins, G., & Tortora, G. J. (2012). Anatomy and Physiology: From Science to Life, 3rd Edition International Stu. John Wiley & Sons.

Muscolino, J. E. (2017). The muscular system manual: The skeletal muscles of the human body.

Download these notes.

Anatomy & Physiology: Muscles—Opponens Digiti Minimi.

Structure.

• Origin: flexor retinaculum and hamate.
• Insertion: medial side of 5th metacarpal.

Function.

• Concentric action: moves little finger across palm to touch the thumb. Lesser: flex little finger at CMC; lateral rotation of little finger at CMC; adduction of little finger at CMC.
• Reverse mover action: flexion, medial rotation and adduction of hamate at 5th CMC.
• Eccentric action: controls/restrains/slows little finger movements at CMC.
• Isometric action: stabilize CMC of little finger.
• Innervation: ulnar nerve.
• Arterial supply: branches of ulnar artery.

Clinical Significance.

More.

• https://www.anatomynext.com/opponens-digiti-minimi-of-hand/
• https://www.youtube.com/watch?v=lWm57mAmg5o
• https://www.youtube.com/watch?v=SUDsq7iqsAc

Opponens digiti minimi. Used with permission by 3D4Medical.

References

Biel, A. (2015). Trail guide to the body: A hands-on guide to locating muscles, bones and more.

Cedars-Sinai. (2018). Vertebrae of the spine. Retrieved from https://www.cedars-sinai.org/health-library/diseases-and-conditions/v/vertebrae-of-the-spine.html

Clark, M., Lucett, S., Sutton, B. G., & National Academy of Sports Medicine. (2014). NASM essentials of corrective exercise training. Burlington, MA: Jones & Bartlett Learning.

Jenkins, G., & Tortora, G. J. (2012). Anatomy and Physiology: From Science to Life, 3rd Edition International Stu. John Wiley & Sons.

Muscolino, J. E. (2017). The muscular system manual: The skeletal muscles of the human body.

Download these notes.

Anatomy & Physiology: Muscles—Flexor Digiti Minimi (fingers).

Structure.

• Origin: flexor retinaculum and hamate.
• Insertion: medial side of proximal phalanx of little finger.

Function.

• Concentric action: flexes pinky finger at carpometacarpal and metacarpophalangeal joints.
• Reverse mover action: flexion of 5th metacarpal at MCP; distally glide the hamate at 5th CMC joint.
• Eccentric action: controls/restrains/slows the CMC and MCP joints of little finger.
• Isometric action: stabilize CMC and MCP of little finger.
• Innervation: ulnar nerve.
• Arterial supply: branches of ulnar artery.

Clinical Significance.

More.

• https://www.anatomynext.com/flexor-digiti-minimi-of-hand/
• https://www.youtube.com/watch?v=JZSnGUYEOkw

Flexor digiti minimi brevis manus. Used with permission by 3D4Medical.

References

Biel, A. (2015). Trail guide to the body: A hands-on guide to locating muscles, bones and more.

Cedars-Sinai. (2018). Vertebrae of the spine. Retrieved from https://www.cedars-sinai.org/health-library/diseases-and-conditions/v/vertebrae-of-the-spine.html

Clark, M., Lucett, S., Sutton, B. G., & National Academy of Sports Medicine. (2014). NASM essentials of corrective exercise training. Burlington, MA: Jones & Bartlett Learning.

Jenkins, G., & Tortora, G. J. (2012). Anatomy and Physiology: From Science to Life, 3rd Edition International Stu. John Wiley & Sons.

Muscolino, J. E. (2017). The muscular system manual: The skeletal muscles of the human body.

Download these notes.

Anatomy & Physiology: Muscles—Abductor Digiti Minimi (fingers).

Structure.

• Origin: pisiform and tendon of flexor carpi ulnaris.
• Insertion: medial side of proximal phalanx of littler finger.

Function.

• Concentric action: abducts and flexes little finger at metacarpophalangeal joint.
• Reverse mover action: abduct 5th metacarpal at MCP; abduct hamate at CMC of little finger; flex 5th metacarpal at MCO; distally glide the pisiform at CMC; extend proximal phalanx of little finger at PIP; extend middle phalanx of little finger at DIP.
• Eccentric action: controls/restrains/slows little finger at MCP, CMC, DIP, and PIP joints.
• Isometric action: stabilize little finger at MCP, CMC, DIP, PIP.
• Innervation: ulnar nerve.
• Arterial supply: branches of ulnar artery.

Clinical Significance.

More.

• https://www.anatomynext.com/abductor-digiti-minimi-of-hand/
• https://www.youtube.com/watch?v=X-JwGGu_97I
• https://www.youtube.com/watch?v=S0aHLPfcDtY
• https://www.youtube.com/watch?v=i-ptRcFtxSU
• https://www.youtube.com/watch?v=15ojdmKkueM

Abductor digiti minimi manus. Used with permission by 3D4Medical.

References

Biel, A. (2015). Trail guide to the body: A hands-on guide to locating muscles, bones and more.

Cedars-Sinai. (2018). Vertebrae of the spine. Retrieved from https://www.cedars-sinai.org/health-library/diseases-and-conditions/v/vertebrae-of-the-spine.html

Clark, M., Lucett, S., Sutton, B. G., & National Academy of Sports Medicine. (2014). NASM essentials of corrective exercise training. Burlington, MA: Jones & Bartlett Learning.

Jenkins, G., & Tortora, G. J. (2012). Anatomy and Physiology: From Science to Life, 3rd Edition International Stu. John Wiley & Sons.

Muscolino, J. E. (2017). The muscular system manual: The skeletal muscles of the human body.

Download these notes.

Anatomy & Physiology: Muscles—Opponens Pollicis.

Structure.

• Origin: flexor retinaculum, scaphoid, and trapezium.
• Insertion: lateral side of first metacarpal.

Function.

• Concentric action: move thumb across palm to little finger (bring thumb and little finger together).
• Reverse mover action: flexion, lateral rotation, and abduction of trapezium.
• Eccentric action: controls/restrains/slows thumb movements.
• Isometric action: stabilizes thumb at CMC.
• Innervation: median nerve.
• Arterial supply: branches of radial artery.

Clinical Significance.

More.

• https://www.anatomynext.com/opponens-pollicis/
• https://www.youtube.com/watch?v=N_jzXYP_pg8
• https://www.nielasher.com/blogs/video-blog/trigger-point-therapy-adductor-pollicis-and-opponens-pollicis
• https://www.youtube.com/watch?v=wmfcjszVVvg

Opponens pollicis. Used with permission by 3D4Medical.

References

Biel, A. (2015). Trail guide to the body: A hands-on guide to locating muscles, bones and more.

Cedars-Sinai. (2018). Vertebrae of the spine. Retrieved from https://www.cedars-sinai.org/health-library/diseases-and-conditions/v/vertebrae-of-the-spine.html

Clark, M., Lucett, S., Sutton, B. G., & National Academy of Sports Medicine. (2014). NASM essentials of corrective exercise training. Burlington, MA: Jones & Bartlett Learning.

Jenkins, G., & Tortora, G. J. (2012). Anatomy and Physiology: From Science to Life, 3rd Edition International Stu. John Wiley & Sons.

Muscolino, J. E. (2017). The muscular system manual: The skeletal muscles of the human body.