Ready Reference Anatomy



Ready Reference Anatomy





Part 1 Alphabetical List of Muscles


Using This Ready Reference


This chapter is intended as a quick source of information about muscles—their anatomical description, participation in motions, and innervation. This information is not intended to be comprehensive, and for depth of subject matter the reader is referred to any of the major texts of human anatomy. We relied on the American1 and British2 versions of Gray’s Anatomy as principal references but also used Sobotta’s Atlas,3 Clemente,4 Netter,5 Hollingshead,6 Jenkins,6 Grant,7 and Moore,8 among others. The final arbiter in all cases was the 38th edition of Gray’s Anatomy (British) by Williams et al.2


The variations in text descriptions of individual muscles remain exceedingly diverse so at times we have consolidated information to provide abstracted descriptions.


Origins, insertions, descriptions, and functions of individual muscles often are abbreviated but should allow the reader to place the muscle correctly and visualize its most common actions; this in turn may help the reader to recall more detailed anatomy.


Nomina Anatomica nomenclature for the muscles appears in brackets when a more common usage is listed.


The entire Ready Reference Anatomy is available on the Evolve site that accompanies this text. Two additional sections are also included, “Part 5. Motions and their Participating Muscles (Motions of the Neck, Trunk, and Limbs)” and “Part 6. Cranial and Peripheral Nerves and the Muscles they Innervate”.













I


176. Iliacus


66. Iliocostalis cervicis


89. Iliocostalis thoracis


90. Iliocostalis lumborum


41. Inferior pharyngeal constrictor [Constrictor pharyngis inferior]


38. Inferior longitudinal (tongue) [Longitudinalis inferior]


84-87. Infrahyoids (see Sternothyroid, Thyrohyoid, Sternohyoid, Omohyoid)


136. Infraspinatus


102. Intercostales externi


103. Intercostales interni


104. Intercostales intimi


164. Interossei, dorsal (hand) [Interossei dorsales]


219. Interossei, dorsal (foot) [Interossei dorsales]


165. Interossei, palmar or volar [Interossei palmares]


220. Interossei, plantar [Interossei plantares]


69. Interspinales cervicis


97. Interspinales thoracis


98. Interspinales lumborum


70. Intertransversarii cervicis


99. Intertransversarii thoracis


99. Intertransversarii lumborum


121. Ischiocavernosus










S


45. Salpingopharyngeus


195. Sartorius


80. Scalenus anterior


81. Scalenus medius


82. Scalenus posterior


194. Semimembranosus


62. Semispinalis capitis


65. Semispinalis cervicis


93. Semispinalis thoracis


193. Semitendinosus


128. Serratus anterior


109. Serratus posterior inferior


108. Serratus posterior superior


206. Soleus


123. Sphincter ani externus


122. Sphincter urethrae


63. Spinalis capitis


68. Spinalis cervicis


92. Spinalis thoracis


61. Splenius capitis


67. Splenius cervicis


83. Sternocleidomastoid [Sternocleidomastoideus]


86. Sternohyoid [Sternohyoideus]


84. Sternothyroid [Sternothyroideus]


35. Styloglossus


76. Stylohyoid [Stylohyoideus]


44. Stylopharyngeus


132. Subclavius


105. Subcostales


134. Subscapularis


43. Superior pharyngeal constrictor [Constrictor pharyngis superior]


37. Superior longitudinal (tongue) [Longitudinalis superior]


145. Supinator


75-78. Suprahyoids (see Mylohyoid, Stylohyoid, Geniohyoid, Digastric)


135. Supraspinatus







Part 2 List of Muscles by Region


Head and Forehead
















Back




61. Splenius capitis (see under Neck)


67. Splenius cervicis (see under Neck)


66. Iliocostalis cervicis (see under Neck)


89. Iliocostalis thoracis


90. Iliocostalis lumborum


60. Longissimus capitis (see under Neck)


64. Longissimus cervicis (see under Neck)


91. Longissimus thoracis


63. Spinalis capitis


68. Spinalis cervicis


92. Spinalis thoracis


62. Semispinalis capitis (see under Neck)


65. Semispinalis cervicis (see under Neck)


93. Semispinalis thoracis


94. Multifidi


71. Rotatores cervicis (see under Neck)


95. Rotatores thoracis


96. Rotatores lumborum


69. Interspinalis cervicis (see under Neck)


97. Interspinalis thoracis


98. Interspinalis lumborum


70. Intertransversarii cervicis (see under Neck)


99. Intertransversarii thoracis


99. Intertransversarii lumborum


100. Quadratus lumborum






Upper Extremity


Shoulder Girdle













Lower Extremity


Hip and Thigh









Part 3 Skeletal Muscles of the Human Body


Muscles of the Forehead


The Epicranius (Two Muscles)





1 Occipitofrontalis


Muscle has two parts






Frontal part (Frontalis)









3 Levator Palpebrae Superioris











4 Orbicularis Oculi


Muscle has three parts










Description:




Forms a broad thin layer that fills the eyelids (see Figure 7-13) and surrounds the circumference of the orbit but also spreads over the temple and cheek. Orbital fibers form complete ellipses. On the lateral side there are no bony attachments. The upper orbital fiber ellipses blend with the occipitofrontalis and corrugator supercilii muscles. Fibers also insert into the skin of the eyebrow forming a depressor supercilii. Medially some ellipses reach the procerus.


The inferior orbital ellipses blend with the levator labii superioris alaeque nasi, levator labii superioris, and the zygomaticus minor.


The fibers of the palpebral part sweep across the upper and lower eyelids anterior to the orbital septum to form the lateral palpebral raphe. The ciliary bundle is composed of a small group of fibers behind the eyelashes.


The lacrimal part fibers lying behind the lacrimal sac (in the medial corner of the eye) divide into upper and lower slips which insert into the superior and inferior tarsi of the eyelids and the lateral palpebral raphe.



Function:




The orbicularis oculi is the sphincter of the eye.


Orbital part: Although closing the eye is mostly lowering of the upper lid, the lower lid also rises and both are under voluntary control and can work with greater force, as in winking.


Palpebral part: Closes lids in blinking (protective reflex) and for sleep (voluntary).


Lacrimal part: Draws the eyelids and lacrimal canals medially, compressing them against the globe of the eye to receive tears. Also compresses lacrimal sac during blinking.


Entire muscle contraction draws skin of forehead, temple, and cheek toward the medial angle of the eye, tightly closing the eye and displacing the lids medially. The folds formed by this action in later life form “crow’s feet.” The muscles around the eye are important because they cause blinking, which keeps the eye lubricated and prevents dehydration of the conjunctiva. The muscle also bunches up to protect the eye from excessive light.






6-9 The Four Recti (Figure 11-1)





Rectus Superior, Inferior, Medialis, and Lateralis




Description:




From their common origin around the margins of the optic canal these straplike muscles become wider as they pass anteriorly to insert on different points on the sclera (see Figure 11-1) The rectus superior is the smallest and thinnest and inserts on the superoanterior sclera under the orbital roof. The inferior muscle inserts on the inferoanterior sclera just above the orbital floor. The rectus medialis is the broadest of the recti and inserts on the medial scleral wall well in front of the equator. The rectus lateralis, the longest of the recti, courses around the lateral side of the eyeball to insert well forward of the equator.



Function:




The ocular muscles rotate the eyeball in directions that depend on the geometry of their relationships and that can be altered by the eye movements themselves. Eye movements also are accompanied by head motions, which assist with the incredibly complex varieties of stereoscopic vision.


The ocular muscles are not subject to direct study or routine assessment. It is essential to know that a change in the tension of one of the muscles alters the length-tension relationships of all six ocular muscles. It is likely that all six muscles are continuously involved, and consideration of each in isolation is not a functional exercise. The functional relationship between the four recti and the two obliquii may be considered as two differing synergies.


The rectus superior, inferior, and medialis act together as adductors or convergence muscles.


The lateral rectus, together with the two obliquii, act as muscles of abduction or divergence.


Convergence generally is associated with elevation of the visual axis, and divergence with lowering of the visual axis.


Neurologists regularly test the ocular muscles when there is an isolated paralysis which gives greater insight into their functions.9


Superior rectus paralysis: Eye turns down and slightly outward. Upward motion is limited.


Medial rectus paralysis: Eyeball turns laterally and cannot deviate medially.


Inferior rectus paralysis: Eyeball deviates upward and somewhat laterally. It cannot be moved downward and the eye is abducted.


Lateral rectus paralysis: The eyeball is turned medially and cannot be abducted.


Inferior oblique paralysis: Eyeball is deviated downward and slightly medially; it cannot be moved upward when in abduction.


Superior oblique paralysis: Here there may be little deviation of the eyeball but downward motion is limited when the eye is adducted. There is no movement toward the midline of the face when looking downward in abduction (intorsion).9



Aug 25, 2016 | Posted by in RHEUMATOLOGY | Comments Off on Ready Reference Anatomy

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