The a-to-z-of-skeletal-muscles

The A to Z of
Skeletal Muscles

Dr A. L. Neill
BSc MSc MBBS PhD FACBS
medicalamanda@gmail.com

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The A to Z of Skeletal Muscles

Introduction
This is the fourth revision of the first A to Z book, and many things

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have changed. The clinical aspects of muscle grouping and testing
has been expanded, due to strong feedback, but the listing of the
muscles and their illustration are largely unchanged.

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There are now 7 in the A to Z series of pocket-sized medical reference
books (see the back of the book for details) - 2 considering organs of
the body, and also 2 posters on medical education on with supportive
website, where all the A to Z material can be accessed as well as
additional material: www.aspenpharma.com.au/atlas/student.htm
Any corrections b/n reprints are placed on this site so that the latest
version and comments re any of the A to Z books may be viewed as
soon as possible.
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As usual the A to Zs get better if there is feedback – please send
us your comments and suggestions.
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Acknowledgement
Thank you ASPENpharmacare Australia for your support & assistance in
this valuable project, particularly Mr. Greg Lan CEO of Aspenpharmacare
Australia, Rob Koster, Richard Clements and Ante Mihaljevic of TM
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Graphic Design & everyone who provided valuable feedback.

Dedication
To AA and ZZ I love you.
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How to use this book
The structure of the A to Z books grows and develops with each
publication, but the principle of listing structures in an alphabetical
manner as far as possible and hence making the book its own index
for easy retrieval has been maintained. However this is now done
after first dividing the material into a number of main topics for
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example muscle groups acting on significant joints, examination,
palpation and testing of muscle groups prior to the main listing of
each and every muscle - excluding some of the detailed Head and
Neck muscles which can be found in the A to Z of the Head & Neck.

1 © A. L. Neill


Features are named using in the most familiar terms and those
agreed upon by anatomical nomenclature convention avoiding

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eponymous terms wherever possible but as with all anatomical
studies sometimes several terms are used to name the same feature.
Wherever this is common and to save confusion reference is made to
each term. Similarly between disciplines such as radiology and

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osteology as well as anatomy the same view may be described
several different ways, so when this is also common and to provide
clarity these terms are mentioned. In some cases with complex
muscles - several views of the same muscle are also supplied.

The text under each muscle in the main listing consists of basic

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minimal information such as the : Origin (O), Insertion (I), Action (A),
Blood Supply (BS), Nerve Supply (NS), Nerve Root origin (NR) and
functional tests (T).
The test section is by no means complete, although in this edition it
has been added to in the front of the book with illustrations of testing
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of major muscle groups. It is also expanded in the A to Z of
Peripheral Nerves and will be further explored in the A to Z of
muscle and PN testing.

Capitalization is used to demonstrate the muscles and bones and
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important components.
It is hoped that this will prove a valuable resource for those working
on muscle examination exercise and recovery in whatever field.

Any suggestions on format or inclusions will be gratefully received
This book is cross-referenced with all the other A to Zs
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Thank you

Amanda Neill
BSc MSc MBBS PhD FACBS
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ISBN 978 0 9806959 6 0

© A. L. Neill 2


Table of contents

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Introduction 1
Acknowledgement 1
Dedication 1

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How to use this Book 1
Table of Contents 3
Abbreviations 4
Common Terms Used in the Study & Examination

Definition of Tendons & Ligaments
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of Skeletal Muscles, Nerves & Bones
Structure & Substructure of Skeletal Muscles
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11
10
Neuro-Muscular Junction 13
Neuro-Muscular Spindle 15
Neuro-Tendinous Spindle 15
Anatomical Planes & Relations 17
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Anatomical Movements 19
Classification, Naming & Examination of Muscles 25
Myotomes 27
Muscle Innervation at the Spinal Cord level 28
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Segmental Motor Nerve Diagram 33
Summaries Of Skeletal Muscle Groups 35
Examination of Skeletal Muscles - major groups 61
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Index - Alphabetical Listing Of Muscles 69

3 © A. L. Neill


LL = lower limb
Abbreviations lig = ligament
A = actions /movements of

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LP = lumbar plexus
a joint Lt. = Latin
aa = anastomosis or anastomoses MC = metacarpal / metacarpo-
adj. = adjective (hand)

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aka = also known as MCP = metacarpo-phalangeal
ALL = anterior longitudinal ligament med = medial
alt. = alternative MT = metatarsal / metatarso (foot)
ant. = anterior N = nerve
art. = articulation (joint w/o the NR = nerve root origin
additional support structures) NS = nervous supply / nerve
AS = Alternative Spelling, generally system
referring to the diff. b/n NT = nervous tissue

(of hip bone)
b/n = between
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British & American spelling
ASIS = anterior superior iliac spine
O
P

pl.
= origin
= phalangeal / phalanges /
phalango-
= plural
BP = brachial plexus PLL = posterior longitudinal
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BS = Blood Supply ligament
C = cervical PN = peripheral nerve
c.f. = compared to post. = posterior
CN = cranial nerve R = right / resistance
CNS = central nervous system ROM = range of motion
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Co = coccygeal S = sacral
CP = cervical plexus sing. = singular
collat. = collateral SC = spinal cord
CSF = Cerebrospinal fluid SN = spinal nerve
CT = connective tissue SP = spinous process / sacral
e.g. = example plexus
EC = extracellular (outside the cell) SS = signs and symptoms
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ES = Erector Spinae group of T = TEST / thoracic
muscles TOS = thoracic outlet syndrome
ext. = extensor (as in muscle to TP = transverse process
extend across a joint) UL = upper limb, arm
Gk. = Greek VB = vertebral body
I = insertion VC = vertebral column
IC = intercarpal / intercarpo - (b/n w/n = within
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wrist) w/o = without
IMC = intermetacarpal wrt = with respect to
IP = interphalangeal (b/n fingers / & = and
toes)
IT = intertarsal / intertarso
jt(s) = joints = articulations
L = lumbar / left

© A. L. Neill 4


Common terms in the Study and Examination of
Skeletal Muscles, Nerves and Bones

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Ala wing used for winglike process e.g. on the hip bone
Ankle bend ie the “bend” b/n the leg and foot
Ante before - in front of
Aperture an opening or space between bones or within a bone

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Aponeurosis expanded end of a tendon - sheet of fibrous tissue
allowing for muscle insertion
Appendicular (skeleton) that which is not axial i.e. the upper and lower limbs
Areolar air filled bone - tooth socket
Articulation joint, which is a point of contact b/n 2 opposing bones
Axial (skeleton) refers to the head & trunk (vertebrae, ribs & sternum)
of the body.
Basilar relating to the base or bottom of structures
Basocranium
Brachi
Brevis
Buccal
base of the skull
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pertaining to the arm (upper arm)
short
relating to the cheek
Canal tunnel / extended foramen
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Capitus/Caput relating to the head
Carpi/Carpo- relating to the wrist
Carotid “to put to sleep” related to the carotid BVs in the
neck which when compressed can put a person to sleep
Cavity/Cavernous an open area or sinus w/n a bone or formed by 2 or
more bones - used interchangeably with fossa.
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Cephalic/Cephalo- pertaining to the head
Cervical/Cerivco- pertaining to the neck
Cilli/Cillia pertaining to the eyelash / hair
Colles referring to the “collar” or neck
Cochlea a snail, snaillike relating to the organ of Corti in the
ear
Condyle a rounded enlargement / process possessing an
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articulating (joint) surface.
Cornu a horn as on the Hyoid bone
Corona a crown. adj.- coronary, coronoid or coronal; hence
a coronal plane is parallel to the main arch of a crown
which passes from ear to ear (c.f. coronal suture).
Costa / Costal referring to the ribs
Cranium / Cranus the cranium of the skull comprises all of the bones of
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the skull except for the mandible, referring to the
skull generally excluding the facial bones
Crest prominent sharp thin ridge of bone formed by the
attachment of muscles particularly powerful ones eg
Temporalis / Sagittal crest
Cuneate / Cuneus a wedge / wedge-shaped
Cutus referring to skin, hence cutaneous branches of Ns go
to the skin
Deltoid D-Shaped
5 © A. L. Neill


Dens / Dentine / Dentate a tooth, relating to teeth, denticulate having tooth-like
projections (see odontoid)
Depression a concavity on a surface

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Diaphragm a partition or separating wall
Diaphysis the body of a long bone. In the young this is the
region between the growth plates.
Digit / Digitorum relating to the fingers or toes

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Dislocation a displacement of anything particularly bone (also
called luxation)
Distal further away from the core opposite to Proximal
Dorsal / Dorsi relating to the back or the back of something e.g. the
hand
Elbow any bend in the arm referring to the elbow b/n arm
and forearm
Eminence a smooth projection on a bone.
Epi-
Epiphysis

Facet
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on top of
the end of a long bone beyond the growth plate
(epiphyseal plate) - 2 epiphyses to each long bone.
a face, a small bony surface (occlusal facet on the
chewing surfaces of the teeth) seen in planar joints.
Femoris pertaining to the thigh
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Fissure a narrow slit or gap from cleft.
Foramen a natural hole in a bone usually for the transmission
of blood vessels and/or nerves. (pl. foramina).
Fornix an arch
Fossa a pit, depression, or concavity, on a bone, or from
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several bones as in temporomandibular fossa - more
like a “bowl” than a cavity
Fovea a small pit (usually smaller than a fossa) - as in the
fovea of the occlusal surface of the molar tooth.
Fracture break # particularly of bone
Genio/Genu pertaining to the knee
Geneio pertaining to the chin adj. geneio
Glossus / Glosso pertaining to the tongue
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Gluteal / Gluteus pertaining to the buttocks
Groove long pit or furrow, as on the Humerus
Hamus a hook hence the term used for bones which “hook
around other bones or where other structures are
able to attach by hooking - hamulus = a small hook.
Hyoid U-shaped
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Incisura a notch.
Inter between (b/n)
Intra within (w/n)
Lacerum something lacerated, mangled or torn eg foramen
lacerum small sharp hole at the base of the skull
often ripping tissue in trauma.
Lacrimal related to tears and tear drops. (noun lacrima)
Lamina a plate as in the lamina of the vertebra a plate of bone
connecting the vertical & transverse spines (pl. laminae)
© A. L. Neill 6


Lesion deficit or injury - lack of function arising from pathology
Ligament fibrous tissue joining bone to bone
Linea a line as in the nuchal lines of the Occiput, linea

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aspera of the Femur
Lingual pertaining to the tongue
Lip projection over the usual margin - e.g. the Glenoid lip
(often pathological)

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Locus a place (c.f. location, locate, dislocate).
Longus long
Lumbar back - generally the lower part of the back (lumbago)
Magnum large pl magna
Mandible from the verb to chew, hence, the movable lower jaw;
adj.- mandibular.
Mastoid a breast or teat shape - mastoid process of the
Temporal bone.
Maxilla

Meatus
maxillary. da
the jaw-bone; now used only for the upper jaw; adj.-

a short passage; adj.- meatal as in external acoustic
meatus connecting the outer ear with the middle ear.
Medulla middle
Mental relating to the chin (mentum = chin not mens = mind)
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Metaphysis the slightly expanded end of the shaft of a bone.
Mylo- relating to the molar teeth (from grinding as in a mill)
Notch an indentation in the margin of a structure.
Nucha the nape or back of the neck adj.- nuchal.
Oblique / Obliquuis pertaining to a slope or slant e.g. muscles slanting
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downwards etc
Occiput the prominent convexity of the back of the head
Occiput = Occipital bone adj. occipital
Oculus / Ocular an eye / relating to an eye
Odontoid relating to teeth, toothlike see Dens
Omo- pertaining to the shoulder
Orbit a circle; the name given to the bony socket in which
the eyeball rotates; adj - orbital.
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Orifice an opening.
Oris / Ora relating to the mouth
Os / Osseus / Ossei a bone / bonelike, referring to bone
Ostium a door, an opening, an orifice.
Ovale Oval shaped
Palate a roof adj.- palatal or platatine.
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Palm / Palmar referring to the palm of the hand - anterior in the
anatomical position
Palpebra pertaining to the eyebrow
Parietal pertaining to the outer wall of a cavity from paries, a wall
Parotid pertaining to a region beside or near the ear
Pars a part of
Pectus/ Pectorial referring to the anterior wall of the chest / breast
Pennate resembling a feather
Peroneus referring to the lower leg adj. - peroneal
7 © A. L. Neill


Phalanx/Phalanges small bones of the fingers or toes - 3/finger (2/thumb
2/big toe)
Piriform pear shaped

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Plantae referring to the sole of the foot adj - plantar
Process a general term describing any marked projection or
prominence as in the mandibular process.
Prominens a projection

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Prone to place face down, or lie on the anterior surface
(opposite supine)
Pterygoid wing-shaped
Pubis/Pubic “hairy”, pertaining to the hairy part of the hip
Quadratus square or rectangular shaped
Radial/Radialis pertaining to the radial or lateral bone of the forearm
Recess a secluded area or pocket; a small cavity set apart
from a main cavity.
Rectus
Rhomboid
Ridge
Risorius
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straight - erect
rhomboid shaped (squashed, leaning square)
elevated bony growth often roughened.
laughter, smile
Root the segments of origin as in Nerve Root (NR) of the
Peripheral Nerve made up from several points of exit
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from the SC
Rotundum round
Sagittal an arrow; the sagittal suture is notched posteriorly,
making it look like an arrow by the lambdoid sutures.
Salpingo pertaining to a tube
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Scalene uneven, one side very different to the other
Sesamoid grainlike
Sigmoid S-shaped, from the letter Sigma which is S in Greek.
Sinus a space usually within a bone lined with mucous
membrane, such as the frontal and maxillary sinuses
in the head, (also, a modified BV usually vein with an
enlarged lumen for blood storage and containing no or
little muscle in its wall). Sinuses may contain air,
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venous or arterial blood, lymph or serous fluid
depending upon location and health of the subject
adj.- sinusoid.
Skull the skull refers to all of the bones that comprise the
head.
Spine a thorn - descriptive of a sharp, slender
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process / protrusion. adj. - spinous
Splanchocranium refers to the facial bones of the skull - most muscles
to this region are innervated by the Facial (CN VII) and
Trigeminal (CN V) nerves.
Subluxation partial dislocation of bone, generally in the VC, used
to account for any mechanical impediment to N function
Sulcus long wide groove often due to a BV indentation
Supine to place face up or to lie on posterior surface
(opposite prone)
© A. L. Neill 8


Suture the saw-like edge of a cranial bone that serves as
joint between bones of the skull.
Stylos an instrument for writing hence adj. - styloid a

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pencil-like structure.
Symphysis a joint or a growth with bone-cartilage-bone
connection e.g. in pubic symphysis
Tarsus / Tarsal pertaining to the Tarsal bone and the bones distal to it

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in the foot (not the toes - phalanges)
Temporal refers to time and the fact that grey hair (marking the
passage of time) often appears first at the site of the
temporal bone.
Tendon fibrous end of a skeletal muscle facilitating attachment
to bone (as opposed to ligament joining bone to bone)
Tensor to stretch (i.e. muscle to stretch so that a structure is
“tense”)
Tentorium
Teres
Thenar
Thorax
a tent.
round shape da
relating to the palm as in thenar eminence
referring to the chest region - anterior the area b/n
the neck and the abdomen
Trabecula a “little” beam i.e. supporting structure or strut pl.
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trabeculae
Trapezoid trapezius or kite shape
Trochanter small wheel or disc-shaped as the disc shape of the
trochanters of the Femur
Trochlear pulley that part of the bone/ligament which pulls
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bones in another direction e.g. in the elbow and ankle
Trunk the area b/n the thorax and the pelvis anterior and
posterior - core muscles generally surround the trunk,
relatively undefined (also referring to large groups of N
fibres organizing to supply a particular region as in
the trunks of the BP)
Tubercle a small process or bump, an eminence..
Tuberculum a very small prominence, process or bump.
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Tuberosity a large rounded process or eminence, a swelling or
large rough prominence often associated with a
tendon or ligament attachment.
Tympanic pertaining to a drum
Uncus a hook adj. - uncinate.
Vagina a sheath; hence, invagination is the acquisition of a
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sheath by pushing inwards into a structure, and
evagination is similar but produced by pushing
outwards adj. - vaginal.
Velum / Veli pertaining to a veil
Volar pertaining to the sole (foot) or palm (hand)
Zygoma a yoke, hence, the bone joining the maxillary, frontal,
temporal & sphenoid bones also referring to the "H"
shape of the bone. adj zygomatic.

9 © A. L. Neill


Definition of Ligament and Tendon

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Ligament (2)= CT band which joins the muscle (1) to the bone
also used to describe any non-specific thickening of CT in organs and
other structures - may incorrectly be used in this sense
interchangeably with Tendon

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Tendon (3)= - CT band which joins 2 bones over a joint or 2
boney points - used for joint stabilization
to limit the ROM of the joint as in the Knee

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2
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3

© A. L. Neill 10


Structure and Substructure of
Skeletal muscles

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1 muscle eg. Biceps

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2 epimysium - CT surrounding a whole muscle
3 perimysium - CT surrounding a muscle fascicle
4 endomysium - CT surrounding each muscle fibre
5 muscle fibre
6 nucleus (note the muscle cell is multinucleated)
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myofibril
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sarcolemma - membrane around each myofibril

sarcomere basic contractile unit of the muscle
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10 myosin filament
11 actin filament

A band - myosin to myosin filaments
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H band - myosin only segments minimum in contraction
I band - actin only segment maximum in relaxation
Z line - line of attachment of the actin filaments
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11 © A. L. Neill


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1

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2
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2 I
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A
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© A. L. Neill 12


Neuromuscular Junction –
Nerve end attaching to Skeletal muscle

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longitudinal

1 axon - sheathed

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2 mylein sheath – multiple lipid layers
3 Schwann cell
4 axonlemma – axon membrane
5 pre-synaptic vesicles
6 axon – unsheathed / naked
7 presynaptic membrane da
8 junctional folds (in sarcolemma)
9 synaptic cleft (~20nm)
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10 mitochondria
11 sarcolemma
12 myofilaments in muscle fibre
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13 © A. L. Neill


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3 4
5 6
11 na da
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© A. L. Neill 14


Neuro-Muscular Spindle –
feedback loop to stop overextension in Skeletal

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muscle

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Neuro-Tendinous Spindle –
feedback loop to tendon

1 capsule of spindle
2 myelinated motor fibres
3 myelinated sensory fibres
4 unmyelinated motor fibres
5 annualospiral fibre endings
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6 bag of nuclei in intrafusal muscle
7 motor end plates
8 muscle fibres i = intrafusal e = extrafusal
9 skeletal muscle nuclei
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10 tendon fibres i = intrafusal e = extrafusal
11 naked axons
12 nuclei in tendon
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15 © A. L. Neill


I

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12
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10e
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© A. L. Neill 16


Anatomical Planes and Relations
This is the anatomical position.

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A = Anterior Aspect from the front Posterior Aspect from the back
used interchangeably with ventral and dorsal respectively
B= Lateral Aspect from either side

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C = Transverse / Horizontal plane
D= Midsagittal plane = Median plane; trunk moving away from this
plane = lateral flexion or lateral movement moving into this
plane medial movement; limbs moving away from this direction
= abduction; limbs moving closer to this plane = adduction
E = Coronal plane
F = Median
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17 © A. L. Neill


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© A. L. Neill 18


Anatomical Movements

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arm extension in sagittal
plane / shoulder movement arm abduction -away from median
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plane / adduction-towards the median
plane -shoulder movement

shoulder extension in
the sagittal plane
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shoulder abduction in the coronal
plane (with elbow flexion)
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wrist extension
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wrist flexion

shoulder elevation
- reverse movement shoulder depression
shoulder movement
19 © A. L. Neill


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back extension / hyperextension
note the back muscles are
contracting
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hip flexion / with back and
shoulder extension
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back lateral flexion shoulder
back rotation
extension and elbow flexion
© A. L. Neill 20


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neck flexion

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neck extension/hyper-extension

lateral flexion
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lateral rotation
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note: extension of the neck is in the normal anatomical position

21 © A. L. Neill


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arm/shoulder movements in the coronal plane
commencing from adduction abduction to extension
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shoulder/scapula movements in
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the horizontal plane

© A. L. Neill 22


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Hip flexion Hip extension
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Hip abduction Hip adduction
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Hip lateral and medial
rotation Hip circumduction
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Knee flexion Knee extension

23 © A. L. Neill


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Foot dorsiflexion Foot plantar flexion

Foot inversion Foot eversion
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Foot normal position

Fingers extension Fingers flexion
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Forearm pronation Forearm supination Hand deviation
radial/laterally
ulna/medially
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Fingers abduction Fingers adduction Thumb opposition

© A. L. Neill 24


Classification, Naming & Examination of Muscles
There are 3 types of muscle tissue and this book discusses only one of them

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SKELETAL MUSCLE. The other 2 are smooth muscle (for the gut and other
areas of involuntary movement) and cardiac muscle (for the heart).

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SKELETAL muscle is defined as muscle which is “striated” or striped,
indicating and ordered cell structure, of myosin and actin filaments, and is
generally under voluntary control, which has an action on the skeleton or
bones in the body.
In its relaxed form the muscle is at its maximum length and this is generally
how the tissue is found. Stimulation generally causes contraction and a
shortening and thickening of the tissue. As it is attached to a minimum of 2
points, the Origin (O) and the insertion (I) - although these may be arbitrarily

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named - this “contraction” brings these 2 points closer together. To reverse
this, another muscle must be attached to 2 different points which when they
move together cause a reversal of the position of the 2 or more affected
bones, hence for each muscle there is an antagonist (opposing muscle) and in
many situations a synergist (a muscle which enhances the original
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movement).

There are a few exceptions to this, for example SPHINCTERS are circular
groups of muscle fibres which upon contraction close the circle they have
formed and may not be attached to bones at all. Their function is to prevent
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leakage or passage of material from one area to another.
Many of the MUSCLES OF FACIAL EXPRESSION are inserted into the deep
fascia of the skin and hence change the soft tissues of the face but do not
affect the bones underneath. We as humans have a great deal of these
muscles, and they may be shifted or injured in many cosmetic procedures
because of this structure.
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Muscle are shaped to allow their contraction to occur in the most efficient
manner, for example sheets of muscles cover expanses of tissue to contain
them, as in the OBLIQUES to contain and move bulky abdominal contents, or
DIAPHRAGMS to separate as well as move large anatomical regions around,
while TERES muscles are small, cordlike, focused groups of fibres for very
specific movements.
Generally the smaller the muscles the deeper they are placed so larger and
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more powerful muscles ones can cover them, for example the GLUTEAL and
ADDUCTOR group of muscles in the leg and buttocks. Smaller muscles
generally have more specific actions, are more resilient but are weaker, they
contract and relax repeatedly for example, to maintain posture or balance, as
in the ROTATORES. Larger, longer muscles by definition cannot be as precise
but have larger ranges of motion and more power and are placed more
superficially - closer to the surface, as in ERECTOR SPINAE.

25 © A. L. Neill


Fibrous tissue inserts give the muscle more strength but less ability to move,
as in RECTUS ABDOMINUS versus TRAPEZIUS, but it is these large

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surface/superficial muscles whose shape can be changed and defined by
gross movement exercises.

Muscles are named using many different criteria singly or in combination: for

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example they may be named according to their action –Supinator, Pronator
and size – Adductor Magnus, Adductor Longus, Adductor Brevis; their shape
and location- Biceps Brachii, Triceps Brachii, Quadratus Lumborum, Interossei,
Intercostals; the direction of their muscle fibres and anatomical layer -
Obliquus Externus Abdominus, Obliquus Internus Abdominus and there does
not seem to be a consistent pattern in this naming - only that from the name
it is often possible to determine their site, action &/or shape and this helps
when memorizing these muscles.

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Between each muscle group is a fascial layer to transport in the BVs and the
Nerves but there is considerable variation in individuals so that in some cases
some anatomists have named the same muscle in several ways. The
commonest has been used here but the alternatives listed if it is thought there
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may be confusion this for example ROTATORES has been listed as a single
muscle group but may in some books be divided into 2 ROTATORES LONGUS
and BREVIS, similarly with PSOAS which can be PSOAS MAJOR and MINOR,
but not with PECTORALIS MAJOR and MINOR, 2 distinct muscles. Wherever
this occurs it is mentioned in the text, particularly if there is a functional
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difference in the 2 muscles.

Testing of a muscle is often impossible to do singly and they must be tested
as an anatomical and functional group. The tests are generally graded 1-5,
with 5 being the strongest and 3 being the point where when appropriate the
muscle can overcome Gravity often a natural form of resistance to the muscle
action. This level of testing muscles is not dealt with in this book and will be
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discussed in the A to Z of Muscle and Sensory testing to follow - it is also
examined in some detail in the A to Z of Peripheral Nerves - however
testing of the primary action of most muscles is listed on each page as a
guide to the practitioner for basic testing and grouping of muscles. Please use
this testing section as a guide only.
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© A. L. Neill 26


Myotomes

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Each muscle is supplied by a particular NR or segment of the SC and the
muscles supplied by the same NR belong to the same MYOTOME. These are
briefly grouped as follows.

Ne
C1,2 neck and upper VC muscles
C3-5 diaphragm
C5 shoulder and upper arm
C6 wrist extension
C7 extension of the elbow
C8 finger movement
T1 finger abduction
T1-12 chest and abdominal muscles
L1,2 hip flexion
da
L3 knee extension
na
L4 foot dorsiflexion
L5 toe movement
S1 plantar flexion of the foot
S2-5 organs of the pelvis and perineum including bladder and bowel and genitals
ma

These muscles are listed in detail in the following table.
rA
©D

27 © A. L. Neill


Muscle innervation at the SC level
SC level Muscle Location

ill
C1 Longus Capitus Neck
Olquuis Capitus Superior Neck - head
Rectus Capitus Anterior Neck - head

Ne
Rectus Capitus Major Neck - head
Rectus Capitus Minor Neck - head
Semispinalis Capitus Neck - head
Trapezius Back

C2 Longus Capitus Neck
Longus Colli Neck - head
Rectus Capitus Anterior Neck - head

C3
da
Sternocleidomastoid
Trapezius

Levator Scapulae
Longus Capitus
Longus Colli
Neck - head
Back

Neck - shoulder
Neck
Neck - head
na
Rhomboideus Major Back - shoulder
Rhomboideus Minor Back - shoulder
Sternocleidomastoid Neck - head
Trapezius Back

C4 Iliocostalis Cervicis Neck - chest
ma

Levator Scapulae Neck - shoulder
Longus Capitus Neck
Trapezius Back

C5 Brachialis Arm
rA

Brachioradialis Arm
Biceps Brachii Arm
Deltoid Shoulder - arm
Iliocostalis Cervicis Neck - chest
Infraspinatus Neck - shoulder
Levator Scapulae Neck - shoulder
Longus Capitus Neck
©D

Pectoralis Major Chest - arm
Scalenus Ant. Medial &Post. Neck
Semispinalis Cervicus Neck
Serratus Anterior Chest
Subscapularis Shoulder
Supraspinatus Shoulder
© A. L. Neill 28


Teres Major Arm - back
Teres Minor Arm - back
Trapezius Back

ill
C6 Abductor Pollicis Longus Hand - thumb
Brachialis Arm
Brachioradialis Arm
Biceps Brachii Arm

Ne
Coracobrachialis Arm - elbow
Deltoid Shoulder - arm
Extensor Carpi Radialis Brevis Forearm - wrist
Extensor Carpi Radialis Longus Forearm - wrist
Extensor Carpi Ulnaris forearm - wrist
Extensor Digitorum Hand - fingers
Extensor Digiti Minimi Hand - little finger
Extensor Indicis Hand - index finger
Extensor Pollicis Brevis Hand - thumb

da
Extensor Pollicis Longus
Flexor Carpi Radialis
Iliocostalis Cervicis
Infraspinatus
Latissimus Dorsi
Hand - thumb
Wrist
Neck - chest
Neck - shoulder
Back - arm
na
Pronator Teres Forearm - wrist
Scalenus Anterior Neck - head
Scalenus Medial Neck - head
Scalenus Posterior Neck - head
ma

Serratus Anterior Chest - arm
Subscapularis Scapula - shoulder
Supinator Forearm - wrist
Supraspinatus Neck -shoulder
Teres Major Arm - chest
Trapezius Back

C7 Abductor Pollicis Longus Hand - thumb
rA

Anconeus Elbow - Arm - Forearm
Brachialis Arm
Brachioradialis Arm
Coracobrachialis Arm - elbow
Extensor Carpi Radialis Brevis Forearm - wrist
Extensor Carpi Radialis Longus Forearm - wrist
Extensor Carpi Ulnaris forearm - wrist
Extensor Digitorum Hand - fingers
©D

Extensor Digiti Minimi Hand - little finger
Extensor Indicis Hand - index finger
Extensor Pollicis Brevis Hand - thumb
Extensor Pollicis Longus Hand - thumb
Flexor Carpi Radialis Wrist
Flexor Digitorum Hand - fingers
Iliocostalis Cervicis Neck - chest
Infraspinatus Neck - shoulder
Latissimus Dorsi Back - arm
Longus Colli Head - neck
29 © A. L. Neill


Pronator Teres Forearm - wrist
Scalenus Anterior Neck - head

ill
Serratus Anterior Chest - arm
Subscapularis Scapula - shoulder
Supinator Forearm - wrist
Supraspinatus Neck - shoulder

Ne
Teres Major Arm - chest
Trapezius Back
Triceps Brachii Arm - elbow

C8 Abductor Digiti Minimi Hand - little finger
Abductor Pollicus Brevis Hand - thumb
Abductor pollicus Longus Hand - thumb
Adductor Pollicus Hand - thumb
Anconeus Elbow

da
Dorsal Interossei
Extensor Carpi Ulnaris
Extensor Digitorum
Extensor Digiti Minimi
Extensor Indicis
Hand - fingers
Wrist
Hand - fingers
Hand - little finger
Hand - index finger
Extensor Pollicis Longus Hand - thumb
na
Flexor Carpi Ulnaris Wrist
Flexor Pollicus Brevis Hand - thumb
Flexor Pollicus Longus Hand - thumb
Iliocostalis Cervicus +Thoracis
Lumbricals Hand - fingers
Opponens Pollicis Hand - thumb
Palmar Interossei Hand - fingers
ma

Pectoralis Major Thorax - chest
Pronator Quadratus Hand

T1 Abductor Digiti Minimi Hand - little finger
Abductor Pollicus Brevis Hand - thumb
Adductor Pollicus Hand - thumb
Dorsal Interossei Hand - fingers
Flexor Carpi Ulnaris Wrist
rA

Flexor Ddigitorum Profundus Hand - fingers
Flexor Digitorum Superficialis Hand - fingers
Flexor Pollicus Brevis Hand - thumb
Flexor Pollicus Longus Hand - thumb
Lumbricals Hand - fingers
Opponens Digiti minimi Hand - little finger
Opponens Pollicis Hand - thumb
Palmar Interossei Hand - fingers
©D

Pectoralis Major Thorax - chest
Pronator Quadratus Hand

L2 Adductor Brevis Hip - thigh
Adductor Longus Hip - thigh
Adductor Magnus Hip - thigh
Gracilis Hip - thigh
Iliacus Hip - thigh
Pectineus Hip
Rectus Femoris Hip - thigh - knee
© A. L. Neill 30


Sartorius Hip - thigh - knee
Vastus Intermedius
Vastus Lateralis Hip - thigh - knee

ill
Vastus Medialis Hip - thigh - knee

L3 Adductor Brevis Hip - thigh
Adductor Longus Hip - thigh
Adductor Magnus Hip - thigh

Ne
IIiacus Hip - thigh
Pectineus Hip
Sartorius Hip - thigh - knee
Vastus Intermedius

L4 Adductor Brevis
Adductor Longus
Adductor Magnus
da
Extensor digitorum Brevis
Extensor Digitorum Longus
Hip - thigh
Hip - thigh
Hip - thigh
Foot - toes
Foot - toes
Extensor Hallucis Longus Foot - big toe
na
Gemellus Inferior Hip
Gluteus Medius Hip
Gluteus Minimus Hip
Iliacus Hip - thigh
Obturator Externus Hip - pelvis
Pectineus Hip
ma

Peroneus Brevis Leg - ankle
Peroneus Longus Leg - ankle
Popliteal Knee
Quadratus Femoris Hip - thigh - knee
Tibialis Anterior Leg - ankle
Vastus Intermedius Hip - thigh - knee
rA


L5 Biceps Femoris Hip - thigh
Extensor Digitorum Brevis Foot - toes
Extensor Digitorum Longus Foot -toes
Flexor Digitorum Brevis Foot - toes
Flexor Digitorum Longus Foot - toes
©D

Flexor Hallucis Longus Foot - big toe
Gemellus Inferior Hip
Gemellus Superior Hip
Gluteus Maximus Hip
Gluteus Medius Hip
Gluteus Minimus Hip
Lumbrical (first) Toe
Oburator Internus Hip - pelvis
Pectineus Hip
31 © A. L. Neill


Popliteal Knee

ill
Semimembranous Hip - thigh - knee
Semitendinous Hip - thigh - knee
Tensor fascia Lata Hip - leg

Ne
Tibialis Posterior Leg - ankle

S1 Biceps Femoris Hip - thigh
S1 Extensor Digitorum Longus Foot - toes
Flexor Digitorum Brevis Foot - toes
Flexor Digitorum Longus Foot - toes
Gastrocnemius Knee - leg

da
Gemellus Inferior
Gemellus Superior
Gluteus Maximus
Gluteus Medius
Gluteus Minimus
Hip
Hip
Hip
Hip
Hip
Lumbrical (first) Toe
na
Pectineus Hip
Piriformis Hip
ma

Tensor fascia Lata Hip - leg
Tibialis Posterior Leg - ankle

S2 Biceps Femoris Hip - thigh
rA

Gastrocnemius Knee - leg
Gemellus Superior Hip
Gluteus Maximus Hip
Lumbricals (2-4) Toes
Piriformis Hip
©D

Soleus Foot - toes
S3 Lumbricals (2-4) Toes

© A. L. Neill 32


Segmental Motor Diagram

ill
Head, upper neck and face supplied by CNs

Ne
C1 neck
C2 infrahyoid
C3
C4
upper limbs
C5 shoulder
C6 Biceps
C7
C8
T1
T2
SPS
da
Triceps

T3 Transverse thoracis
na
T4

T5 Intercostals

T6
ma

T7

T8 Abdominal obliques

T9 SPI
rA

T10
T11 Hip flexion
T12
L1 QL
L2
L3
L4
L5
©D

S1
S2 Pelvis Lower limbs
S3
S4 Perineal muscles
S5

33 © A. L. Neill


ill
Ne
na da
ma
rA
©D

© A. L. Neill 34


Summaries of Skeletal Muscle Groups

ill
Muscles of the arm
Muscles of the arm and shoulder

Ne
Deltoid
Rotator Cuff muscles Subscapularis,
Supraspinatus, Infraspinatus,
Teres Major & Minor
NS from the BP – C5-7
BS from the axillary artery & branches

External Rotators = Lateral Rotators

Infraspinatus Teres Minor
na da
ma
rA

Internal Rotators = External Rotators

Latissimus Dorsi Teres Minor
©D

35 © A. L. Neill


Muscles connecting the arm with the VC
Levator Scapulae

ill
Rhomboids Major & Minor
Trapezius
Latissimus Dorsi
NS segmental (C2-T12)

Ne
BS from dorsal branches of the aorta

Muscles connecting the arm with the chest wall
Pectoralis Major & Minor
Serratus Anterior
Subclavius

segmental NS and BS from the axillary and long thoracic

da
Muscles in the anterior compartment of the arm - flexors
Biceps Brachii
Coracobrachialis
Brachialis
na
NS musculocutaneous (C5-6)
BS brachial

Muscles in the posterior compartment - extensors
Triceps Brachii
ma

NS radial (C7-8)
BS profunda brachii and branches
rA
©D

© A. L. Neill 36


Muscles of the forearm

ill
anterior superficial
Pronator Teres
Palmaris Longus
Flexor Carpi Radialis

Ne
Flexor Carpi Ulnaris
intermediate
Flexor Digitorum Superficialis
deep
Flexor Pollicis Longus
Flexor Digitorum Profundus
Pronator Quadratus

posterior superficial
da
NS median and ulnar Ns - BS radial branches

Extensor Digitorum
na
Extensor Digiti Minimi
Extensor Carpi Ulnaris
Anconeus
deep
Supinator
Abductor Pollicis Longus
ma

Extensor Pollicis Longus & Brevis
Extensor Indicis
NS radial (C7-C8)
BS radial and interosseous branches
rA
©D

37 © A. L. Neill


Intrinsic muscles of the hand

ill
THENAR EMINENCE (Side of the thumb)
Muscles: Abductor Pollicus Brevis
Flexor Pollicus Brevis

Ne
Opponens Pollicus

NS: median, C8
BS: median, medial of Superfical and Deep Palmer anastomoses

HYPOTHENAR EMINENCE (Side of the little finger)
Muscles: Abductor Digiti Minimi
Flexor Digiti Minimi

NS: ulnar, T1
da
Oppons Digiti Minimi

BS: ulnar, lateral of Superfical and Deep Palmer anastomoses
na
OTHER
Muscles: Adductor Pollicus
Lumbricals (4)
Interossei (7-8)
Palmar and Dorsal
ma

BS: ulnar and radial, palmar anastomoses and digital branches
rA
©D

© A. L. Neill 38


Muscles of the Hip and Buttocks (Gluteal region)

ill
Gluteus Maximus, Medius, Minimus

Lateral – External Rotators
1 Obturator Externus

Ne
2 Obturator Internus
3 Gemellus Inferior
4 Quadratus Femoris
5 Gemellus Superior
6 Piriformis
Medial – Internal Rotators
7 Gluteus Minimus
8 Tensor Fascia Lata (part of the ITB)

NS local L4-S2
BS superior gluteal
na da
6
ma

5 1

4
rA

2

7

8
©D

39 © A. L. Neill


Muscles of the gluteal region

ill
Muscles: Gluteus Maximus
Medius and Minimus
Piriformis
Superior and Inferior Gemellus

Ne
Obturator Internus
Quadratus Femoris

NS: local, L4-S2
BS: superior gluteal

Muscles and muscle layers of the chest and abdomen
da
superficial
Pectoralis Major & Minor
Serratus Anterior & Posterior
Rectus Abdominus
na
middle
External & Internal Intercostals
External & Internal Obliques
deep
Innermost Intercostals
ma

Levator Costi Longus & Brevis
Tranversus Thoracics
Transverses Abdominus
Quadratus Lumborum

NS segmental (C3-L2)
BS from C3-L2
rA
©D

© A. L. Neill 40


Muscles of the Hip and Thigh

ill
anterior compartment muscles - hip flexors / knee extensors
Sartorius
Iliopsoas
Pectineus

Ne
Quadriceps Femoris = Vastus Intermedius +
V. Lateralis V. Medialis + Rectoris Femoris (deep)

NS femoral N (L2-5)
BS femoral

da
posterior compartment muscles - hip extensors /knee flexors
Hamstrings = Semimembranous +
na
Semitendinous + Biceps Femoris
Adductor Magnus

NS sciatic N (L2-S2)
BS profunda femoris
ma

medial compartment muscles - hip adductors
Gracilis
Adductor Magnus, Longus, Brevis
rA

Obturator Externus
Pectineus

NS obturator N (L2-4)
BS obturator, profunda femoris
©D

lateral compartment - abductor (not really a compartment)
Tensor Fascia Lata - part of the Iliotibial tract

NS superior gluteal (L4-S1)
BS superior gluteal, lateral femoral circumflex

41 © A. L. Neill


Muscles of the leg

ill
anterior compartment muscles - dorsi-flexors of the
ankle, extensors of the toes
Extensor Digitorum Longus
Extensor Hallicus Longus

Ne
Peroneus Tertius
Tibialis Anterior

NS deep peroneal N (L5-S1)
BS anterior tibial
na da
lateral compartment muscles - evertors
Peroneus Brevis. Longus

NS superficial peroneal N (S1-2)
BS peroneal
ma
rA

posterior compartment muscles - plantar-flexors

superficial Gastrocnemius, Plantaris, Soleus
deep Extensor Digitorum Longus
©D

Flexor Hallicus Longus, Popliteus
Tibialis Posterior

NS tibial N (L4-S3)
BS posterior tibial

© A. L. Neill 42


Intrinsic muscles of the sole of the foot

ill
Dorsal surface of the foot - dorsi-flexors
Extensor Digitorum Brevis
Extensor Hallicus Brevis and Dorsal Interossei (intrinsic muscles of

Ne
the foot) and the tendons of the Longus Extensors cross over this
surface (not shown).

NS deep peroneal N (S1-2)
BS dorsalis pedis
na da
Plantar surface
superficial layer - closest to the surface of the sole of the foot
Abductor Hallicus
Flexor Digitorum Brevis
Abductor Digiti Minimi
ma
rA
©D

43 © A. L. Neill


second layer

ill
Quadratus Plantae
Lumbricals and tendons of the Flexors of the toes and
big toe

Ne
third layer
na
Adductor Hallicus
Flexor Digiti Minimi
da
Flexor Hallicus Brevis

fourth and deepest layer of the sole - closet to the bones
Interossei
Tendons of Peroneus Longus and Tibialis Posterior

NS lateral plantar (S1-3)
ma

BS lateral plantar
rA
©D

© A. L. Neill 44


Muscles and muscle layers of the Back and Neck

ill
NECK - has 2 major groups of muscles

1 those concerned with the neck movement
i.e. movement of the cervical spine and head;

Ne
2 those concerned with the anterior neck structures.
These muscles are dealt with in the laryngeal, pharyngeal and other related
structures.
Other muscles are concerned with the anterior regions of the head and are
mentioned here.

deep posterior - suboccipital muscles - extensors (see the next page

stabilizers da
included with the back muscles) / hyperextensors / rotators and

Rectus Capitus Posterior - Major and Minor
Obliquuis Capitus muscles
Cervical and Cephalic / Capitus regions of the muscles of the VC
na
NS segmental - dorsal rami of the related SNs
BS dorsal branches of the carotids

deep anterior - prevertebral A
flexors, rotators and stabilizers
ma

Rectus Capitus Anterior and Lateral
Longus Colli and Capitus

NS segmental - ventral rami of related SNs
BS branches of carotids and other local vessels
rA

anterior - flexors, rotators B
Scalenii muscles
NS segmental anterior branches of the ventral rami
BS superficial cervical
©D

45 © A. L. Neill


BACK - has 2 major groups of muscles

ill
1 those which are intrinsic to the VC basically segmental muscles
concerned with movements and stability of the VC particularly the
deepest layers - connected with the movement of the neck etc.
2 those which use the VC as an immoveable post and move structures

Ne
around the back extrinsic concerned with the anterior neck structures.

EXTRINSIC
muscles which move the shoulder and arm
Trapezius, Latissimus Dorsi, Rhomboids
Levator Scapulae
muscles which move the rib cage

da
Serratus Posterior inferior and superior

NS segmental - ventral rami of related SNs
BS branches of carotids and other local vessels

INTRINSIC
na
most superficial
Erector Spinae - ES divided into a number of muscle groups with regional
distinctions
medial lateral
Spinalis Iliocostalis Longissimus
ma

Iliocostalis - Lumborum, Thoracis, Cervicus
Longissimus - Thoracis, Cervicus, Capitus
Spinalis - Thoracis, Cervicus, Capitus

O & I listed individually in the text
as a group
rA

O along the VC, Sacrum and Ribs
I into the VC and Ribs
A listed individually
A as a group the ES extends and rotates the VC
NS - segmental spinal roots generally the dorsal rami but may alos have
innervation from the dorsal branches of the ventral rami branches (C1-
L5) - cervical and capitus regions act upon the neck
©D

BS - segmental dorsal branches of the descending aorta, lumbar and sacral
arteries
T - to stand up from touching toes w/o help
- from upright position bend to one side and the other w/o help

47 © A. L. Neill


The summary below is brief and only an overview of these muscles for
completeness of this muscle book. They are discussed in individual
detail in the A to Z of the Pelvis and Perineum and the A to Z of Surface

ill
Anatomy.

Muscles of the Perineum

Ne
(only female anatomy shown)

Anterior - urogenital triangle bordered by the pubic arch and
ischeal tuberosities and overlaid by the structures of the Vulva.
Bulbospongiosus surrounding the urethra and vagina combined and
compressing their orifices during coitus
Ischiocavernosus encasing glandular tissue which contacts in coitus
to expel the contents

da
Sphincter Urethrae = Urethral Sphincter
sphincter hence circular muscle inserting all around
natural position - constricted rather than relaxed
Transverse Perineal - Profundus between the perineal fascae,
Superficialis
na
these muscles overlie each other with the
perineal diaphragm in b/n
Superficialis - inferior to Profundus hence closer to the skin

NS pudendal (S2-4)
ma

BS pudendal

Posterior - anal triangle bordered by the ischeal tuberosities
and the coccyx
Coccygeus from the isheal spine tom the coccyx
Levator Ani = Pubococcygeus + Iliococcygeus
Sphincter Ani = External Anal Sphincter Ischiococcygeus
rA

sphincter hence circular muscle inserting all around
natural position - constricted rather than relaxed

A muscles of this region act to support the pelvic contents and the perineum
and are intimately related so that damage to any of this basin of tissue will
have profound effects on the functional capacities of the others.
©D

NS pudendal and Ns from SP (S2-4)
BS internal iliacs

49 © A. L. Neill


The summaries below are brief and only an overview of these muscles
for completeness of this muscle book. They are discussed in individual
detail in the A to Z of the Head and Neck.

ill
Muscles of the Eye - note all 6 of these muscles act “in concert” in
eye movement and depend upon the fixation and focus of the eye

Ne
Extrinsic
Muscles responsible for movement of the upper eyelid
Levator Palpebrae Superioris
NS occulomotor N (CNIII)
BS supraorbital, branches of ophthalmic

da
Muscles responsible for movement of the eyeball
Recti muscles - Inferior /Superior, Medial/Lateral.
These muscles are straight and are responsible for one
movement up/down, in/out
Oblique muscles - Inferior, Superior
na
These muscles are attached via a trochlea or pulley and
movements therefore vary on eye position
and are diagonal up and out/ down and in

All are attached to the scleral surface, the Recti via the optic canal on
the common annular tendon, and the Obliques via bones in the optic
ma

cavity

NS oculomotor N (CNIII) - except Lateral Rectus - abducent N (CNVI) and
Superior Oblique - trochlea N (CNIV)
BS ophthalmic and branches of internal carotid
rA

Intrinsic
These muscles are responsible for moving structures within the eyeball
and are not shown.

NS oculomotor N (CNIII) also branches from the autonomic NS
BS ophthalmic and branches of internal carotid
©D

Ciliaris, Dilator Pupillae, Sphincter Pupillae

51 © A. L. Neill


Muscles of the Face

ill
Expression
Buccinator - see individual listing
Corrugator Supercili - see individual listing
Depressor Anguli Oris, see individual listing

Ne
Depressor Labii Inferioris, see individual listing
Depressor Septi see individual listing
Frontalis (of Occipitofrontalis), see individual listing
Incisivus Labii Superioris & Inferioris
These muscles insert into the other muscles of the mouth and assist
Orbicularis Oris in protruding the lips
Levator Anguli Oris (Caninus),
Levator Labii Superioris
Levator Labii Superioris alaeque nasi da
These muscles evert the upper lips medially and laterally assisting Orbicularis
Oris and the Zygomaticus muscles
Mentalis see individual listing
na
Nasalis (compressor & dilator)
These muscles change the aperature of the nares (nostrils) assisting
Depressor Septi
Orbicularis Oculi see individual listing
Orbicularis Oris see individual listing
Platysma see individual listing
ma

Procerus
This muscle depresses the medial end of the eyebrow assisting both
Orbicularis Oculi and Corrugator Supercili
Risorius see individual listing
Zygomaticus Major & Minor see individual listing
rA

NS facial N (CNVII)
BS facial
These muscles are often involved in cosmetic surgery and their function may
be compromised by incisions at the level of the deep fascia.

Mastication
©D

Masseter, see individual listing
Pterygoids Lateral, Medial see individual listing
Temporalis see individual listing
All are attached to the Mandible - Jaw bone and part of the
Splanchnocranium

NS trigeminal N (CNV)
BS trigeminal and facial branches
53 © A. L. Neill


Muscles of the Thyroid & Hyoid

ill
- superficial anterior neck muscles
- muscles of the Anterior Triangle
- strap muscles

Ne
Digastricus - see individual muscle listing
Geniohyoid
Mylohyoid

These muscles elevate and position the Hyoid and the floor of the mouth to
facilitate swallowing and occlusion of the Larynx
NS hypoglossal and C1 of ansa cervicalis BS facial branches

Omohyoid
Sternohyoid
Sternothyoid
da
These muscles depress the Hyoid after swallowing
na
NS ansa cervicalsis C1-3 BS thyroid vessels

Stylohyoid
Thyrohyoid
ma

These muscles are involved in support of swallowing - Thyrohyoid both lowers
and elevates the Hyoid
NS ansa cervicalis C1-3 BS facial and thyroid vessels

As a group, these muscles define the neck line and shape, are involved in
swallowing and sound production may be tightened in cosmetic surgery - they
may attach to the Hyoid, Sternum and other bones in the region as a
rA

“through” bones - i.e. they have fascial slings to support them and separate
them into 2 muscle bellies.
©D

55 © A. L. Neill


Muscles of the Larynx and Pharynx

ill
Salpingopharyngeus - attaches to the inferior of the auditory tube and
blends with Palatopharyngeus to raise the pharyngeal wall close off the
auditory tube for swallowing

Ne
Palatopharyngeus - attaches to the Thyroid cartilages and the Palate to bring
the pharynx forward allowing food to leave the mouth and enter the pharynx

Stylopharyngeaus - attaches to the styloid process and the constrictors to
elevate and dilate the pharynx in the early stages of swallowing

Pharygneal Constrictors - superior, middle, inferior - attach to the Medial

da
Pterygoid plate, Hyoid and Thyroid cartilages and blend in with each other and
the posterior root of the tongue in order to commence swallowing and the
resultant peristaltic movement -

NS vagus (CNX) and branches of ansa cervicalis (C1-3)
na
BS maxillary, facial

Note in CVAs - strokes these muscles under voluntary control and are involved
in the early stages of swallowing - so may be affected greatly limiting the
person’s capacity to swallow
ma

Cricothyroid - attached to the laryngeal cartilages
Arytenoids muscles attached to the arytenoids cartilages at the back of the
vocal cords responsible for altering the shape and angle of these cartilages
Cricoarytenoids - posterior and lateral, Thyroarytenoid, Transverse
arytenoids,
Vocalis - also attached to the arytenoids cartilages for voice regulation.
rA

NS for most of these muscles comes from the vagus (CNX)
BS from the thyroid vessels and branches of the carotids
©D

57 © A. L. Neill


Muscles of the Soft Palate

ill
Levator Veli Palatini - attaches to the inferior surface of the Temporal bone
to lift the soft palate and separate the naso and oropharynx

Muscularis Uvulae - attaches to the posterior spine of the Palatine bone and

Ne
the Uvula to elevate it

Palatoglossus - attaches to the oral surface of the Palate to the side of the
tongue to allow the tongue to rise and shut off the mouth from the oropharynx

Tensor Veli Palatini - attaches to the side of the auditory tube and medial of
the spine of the Sphenoid bone to the hard palate to close both the naso and
oropharynx
da
NS mainly from glossopharyngeal N (CN IX)
BS facial palatine vessels and branches

It is changes in these muscles which may result in snoring and sleep
na
apnea.
ma
rA
©D

59 © A. L. Neill


Muscles of the Tongue

ill
Extrinsic
Genioglossus - attaches to the Hyoid, Pharyngeal constrictors, Hypoglossus
and intrinsic Lingualis muscles to protrude tongue (poke out the tongue)
depress the centre and raise the sides (make a tunnel with the tongue)

Ne
Hyoglossus - attaches to the front and horns of the Hyoid, side of the tongue
and intrinsic Lingualis muscles in order to depress the tongue (as in say
AHHHHH…)

Styloglossus - attaches to the styloid process, and blends with the
Hypoglossus, Stylohyoid

Intrinsic da
Linguali muscles - superior, inferior, transverse and vertical
attach w/in the tongue to change its shape for speech, in mastication and
swallowing
na
NS lingual, sublingual and hypoglossal (CNXII) Ns
BS lingual, sublingual and external carotid
ma
rA
©D

© A. L. Neill 60


Examination of Skeletal Muscles - major groups

ill
note detailed examinations of individual muscles are listed in the A to Z of Sensory and
Muscles testing as well as general testing listed after each muscle in the text. ROM and
a selection of strength tests of major movements are included here
Hx - questions for individual joint examination

Ne
1 functional limitation
2 SS -limited to one or more joints
3 onset - acute - related to a specific incident
- chronic - slow progressive increase of pain or reduced ROM
4 description of the causative agent if known e.g. accident
5 any prior MSS history of that joint or others
6 Systemic problems
Ex - for participation in sport/training activities MSS

positions for specific testing da
for this examination unless otherwise indicated the patient standing - facing the clinician
in the anatomical position - included are several tests with the patient in alternative

CERVICAL SPINE / NECK - ROM tests the following groups of muscles
Scalenes/Colles/Trapezius upper fibres/Cervicis regions of ES and deep muscles of the
VC/Sternocleidomastoid
na
patient looks at the roof ± R extension
patient looks at the floor ± R flexion
patient looks over each shoulder ± R horizontal rotation
head bends towards the shoulder - sideways ± R
(shoulders kept still) lateral flexion
ma

SHOULDER (SCAPULA) - ROM tests the following groups of muscles
Levator Scapulae/Rhomboids/Serratus Anterior/Spinati muscles/Trapezius/Deltoid
observe symmetry of shoulder particularly the Acromioclavicular jt
shrug shoulders ± R elevation
drop shoulders depression
straighten shoulders - trying to meet shoulder blades lateral rotation
contract shoulders - withdrawing chest medial rotation
abduct shoulders to 90o (flexed arm) ± R abduction
rA

Strength tests - Shoulder
©D

61 © A. L. Neill


SHOULDER + ARM - ROM tests the following groups of muscles
Pectorals/Latisimus Dorsi/Trapezius/Scapular muscles

ill
scratch back with each hand from over and under the shoulder or
have hands meet at the back from over and under the shoulder
external rotation + abduction
internal rotation + adduction
move extended abducted arms as high as possible ± R vertical adduction

Ne
move extended abducted arms into the sagittal plane ± R horizontal adduction
move extended abducted arms out of the sagittal plane ± R horizontal abduction
with bent arms keep them close to the body against R adduction

full ROM of the shoulder,
scapula and upper limb
na da
UPPER LIMB + HAND - ROM tests the following groups of muscles
Brachii muscles/Brachioradialis/Flexors & Extensors of upper limb, hand &
digits/Supinators/Pronators/Carpi muscles/Intrinsic muscles of the hand
flex/extend elbows ± R
turn wrist in and out ± R pronation/supination
ma

bend and straighten wrist ± R flexion/extension
move extended wrist towards the body ± R ulnar deviation = medial
flexion
move extended wrist away from the body ± R radial deviation = lateral
flexion
spread extended fingers ± R abduction
close extended open fingers ± R adduction
oppose fingers and thumb opposition
rA

make a fist ± R flexion
extend hand and fingers ± R extension
Strength tests - Shoulder
©D

testing elbow extension / flexion

© A. L. Neill 62


Forearm Testing pronation and supination

ill
Ne
Wrist
na da
testing extension flexion

Fist
ma

note the normal fist has all fingers pointing to the
scaphoid tubercle normal flaxion of the IP joints
rA

Thumb thumb adduction opposition
©D

63 © A. L. Neill

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