Category: Muscles

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Structure.

• Origin: anococcygeal ligament.
• Insertion: perineal body of perineum.
• Spans above and below the pectinate (dentate) line.

Function.

• Concentric action: keeps anal canal and anus closed.
• Isometric action:
• Innervation: sacral spinal nerve S4 and inferior rectal branch of pudendal nerve.
• Arterial supply: superior rectal artery, contributions from middle rectal and median sacral arteries (above dentate line); inferior rectal artery from internal pudendal artery (below dentate line).

Clinical Significance.

External anal sphincter. Used with permission by 3D4Medical.

References

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

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.

Structure.

• Origin: perineal body.
• Insertion: blends with partner on other side anterior to urethra.

Function.

• Concentric action: accessory sphincter of urethra; aids in closing vagina.
• Isometric action:
• Innervation: perineal branch of the pudendal nerve of sacral plexus.
• Arterial supply: perineal branch of pudendal artery.

Clinical Significance.

Sphincter urethro vaginalis. Used with permission by 3D4Medical.

References

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

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.

Structure.

• Origin: ischial and pubic rami.
• Insertion: median raphe in male and vaginal wall in female.

Function.

• Concentric action: accessory sphincter of urethra.
• Isometric action:
• Innervation: perineal branch of the pudendal nerve of sacral plexus.
• Arterial supply: males, bulbourethral artery; female, internal pudendal artery from the internaliliac artery.

Clinical Significance.

Compressor urethrae. Used with permission by 3D4Medical.

References

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

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.

Structure.

• Origin: ischial and pubic rami.
• Insertion: median raphe in male and vaginal wall in female.

Function.

• Concentric action: aids in expelling last drops of urine and semen in male and urine in female.
• Isometric action:
• Innervation: sacral spinal nerve S4 and inferior rectal branch of pudendal nerve.
• Arterial supply: males, bulbourethral artery; females, internal pudendal artery from the internaliliac artery.

Clinical Significance.

External urethral sphincter. Used with permission by 3D4Medical.

References

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

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.

Structure.

• Origin: ischial rami.
• Insertion: perineal body of perineum.

Function.

• Concentric action: helps expel last drops of urine and semen in male and urine in female.
• Isometric action:
• Innervation: perineal branch of pudendal nerve of sacral plexus.
• Arterial supply: perineal branch of the internal pudendal artery.

Clinical Significance.

Deep transverse perineal. Used with permission by 3D4Medical.

References

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

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.

Structure.

• Origin: ischial tuberosity and ischial and pubic rami.
• Insertion: corpus cavernosum of penis in male and clitoris in female.

Function.

• Concentric action: maintain erection of penis in male and clitoris in female.
• Isometric action:
• Innervation: perineal branch of pudendal nerve of sacral plexus.
• Arterial supply: perineal artery.

Clinical Significance.

Ischiocavernosus. Used with permission by 3D4Medical.

References

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

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.

Structure.

• Origin: perineal body of perineum.
• Insertion: perineal membrane of deep muscles of perineum corpus spongiosum of penis, and deep fascia on dorsum of penis in male; pubic arch and root and dorsum of clitoris in female.

Function.

• Concentric action: aids in expelling urine, propel semen, assists in erection, constricts vaginal orifice and assists in erection of clitoris in female.
• Isometric action:
• Innervation: perineal branch of pudendal nerve of sacral plexus.
• Arterial supply: internal pudendal artery and its branch (perineal artery).

Clinical Significance.

Bulbospongiosus. Used with permission by 3D4Medical.

References

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

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.

Structure.

• Origin: ischial tuberosity.
• Insertion: perineal body of perineum.

Function.

• Concentric action: stabilize perineal body of perineum.
• Isometric action:
• Innervation: perineal branch of pudendal nerve of sacral plexus.
• Arterial supply: perineal branch of the internal pudendal artery.

Clinical Significance.

Superficial transverse perineal. Used with permission by 3D4Medical.

References

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

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.

Structure.

• Origin: ischial spine.
• Insertion: lower sacrum and upper coccyx.

Function.

• Concentric action: support/maintain position of pelvic viscera; resists increase in intra-abdominal pressure (during forced exhalation coughing, vomiting, urination, defecation, childbirth); constrict anus, urethra, and vagina.
• Isometric action:
• Innervation: sacral spinal nerves S4-S5.
• Arterial supply: inferior gluteal artery.

Clinical Significance.

More.

• https://www.imaios.com/en/e-Anatomy/Anatomical-Parts/Ischiococcygeus-Coccygeus
• https://youtu.be/ZqGzXp8AeN0

Ischiococcygeus. Used with permission by 3D4Medical.

References

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

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.

Structure.

• Levator ani has two parts: pubococcygeus and iliococcygeus.

Function.

• Concentric action:
• Reverse mover action:
• Eccentric action:
• Isometric action:
• Innervation:
• Arterial supply:

Clinical Significance.

More.

• https://youtu.be/ZaIRPhXavVg
• https://www.pelvicrehabilitation.com/rectal-pain-levator-ani-syndrome-video/
• https://www.youtube.com/watch?v=R8FJJN6pn-M

Levator Ani. Used with permission by 3D4Medical.

References

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

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.