Download Muscle Identification, Origin, Insertion, and Action Groups 1-6

Muscle
Identification,
Origin, Insertion,
and Action
Groups 1-6
Taft College
Human Anatomy
Flexors of
wrist
Muscle Identification
Anterior View
Extensors
of wrist
Muscle Identification
Posterior View
1. Muscles of the Head
Muscles of Mastication
MUSCLE
EL
*MASSETER
x
*TEMPORALIS
x
Muscles of Mastication:
Action: Elevation of the mandible
Depression of the mandible is caused in part by muscles (platysma) you do not
need to know. Depression of mandible is also aided by gravity.
*Masseter O: zygomatic arch I: ramus of mandible A: elevates mandible
*Temporalis O: temporal fossa I: coronoid process A: elevates mandible
1. Muscles of Head (Mastication)
2. Muscles of Neck and Vertebral Column
MUSCLE
F
SPLENIUS CAPITUS
*STERNOCLEIDOMASTOID
x
x
RO
LF
x
x
x
ERECTOR SPINAE =
(Sacrospinalis)
(Iliocostalis)
(Longissimus)
(Spinalis)
Fig 11.9 p.274
*Rectus abdominus
Fig.11.11 p.278
E
x
Actions at the neck and vertebral column:
Flexion, extension, rotation, lateral flexion
x
Splenius capitus
O: cervical vertebra I: mastoid process
A: extension, rotate neck
Antagonists:
Splenius capitus: extension of neck
Sternocleidomastoid: flexion of neck
Work together in rotation
2. Muscles of Neck and Vertebral Column
*Sternocleidomastoid O: sternum, clavicle I: mastoid process
A: flexion, rotation, lateral flexion of neck
2. Muscles of Neck and Vertebral Column
Muscles of Head and Neck
Sacrospinalis (erector spinae)
O: spinous processes, iliac crest,
sacrum, lumbar vert., transverse
processes,
I: transverse processes, ribs
A: extension of vertebral column
Erector spinae = Sacrospinalis
Deep muscles of back
3 muscles in erector spinae
group = iliocostalis,
longissimus, spinalis
2. Muscles of Neck and Vertebral Column
*Rectus abdominus
O: symphysis pubis
I: costal cartilage
A: flexion of vertebral column
also aids forced expiration and
raise intra-abdominal pressure
2. Muscles of Neck and Vertebral Column
3. Muscles that Move the Shoulder
Girdle (Scapula)
MUSCLE
EL
* TRAPEZIUS (UPPER)
X
DEP
AB
DR
X
*TRAPEZIUS (LOWER)
X
LEVATOR SCAPULAE
X
RHOMBOIDS (Major,
Minor)
X
SERRATUS ANTERIOR
UR
X
*TRAPEZIUS (MIDDLE)
PECTORALIS MINOR
AD
X
X
X
X
X
X
X
X
Actions: elevation, depression, abduction, adduction, upward rotation,
downward rotation. (rotation refers to movement of glenoid cavity)
All actions cause movement of the scapula. Therefore these muscles have
insertions on scapula and origins on axial skeleton as an anchor.
Actions the Shoulder Girdle (Scapula)
Elevation
Upward Rotation
Downward Rotation
Adduction
Abduction
Rotation of scapula
refers to relative
movement of Glenoid
cavity.
Depression
*Trapezius
O: occipital bone, cervical and
thoracic spine
I: clavicle, spine of scapula
A: elevate, depress, adduction,
upward and downward rotate of
scapula
The trapezius is a composite
muscle (made of multiple
muscles in other animals) with
fibers in the upper, middle, and
lower portions running in
different directions to cause
multiple actions.
It is even antagonistic to itself!
3. Muscles that Move the Shoulder
Girdle (Scapula)
Levator scapulae
O: transverse process of cervical
spine
I: medial border of scapula
A: elevation of scapula
3. Muscles that Move the Shoulder
Girdle (Scapula)
Rhomboids (major & minor)
O: spine
I: medial border of scapula
A: elevation, adduction and
downward rotation of scapula
Rhomboids
3. Muscles that Move the Shoulder
Girdle (Scapula)
Pectoralis minor
O: ribs 3-5
I: coracoid process
A: Depression, abduction, downward rotation of scapula
Depression,
abduction,
downward rotation
of scapula
3. Muscles that Move the Shoulder
Girdle (Scapula)
Serratus anterior O: ribs I: ventral surface of medial border of scapula
A: abduction, upward rotation of scapula
3. Muscles that Move the Shoulder
Girdle (Scapula)
4.Muscles that Move the Shoulder Joint (Humerus)
MUSCLE
F
CORACOBRACHIALIS
X
X
*PECTORALIS MAJOR
X
X
X
X
X
*TERES MAJOR
*TERES MINOR
E
X
X anterior
X posterior
•
•
•
•
X
X
X
RC
LR
X lateral
RC
LATISSIMUS DORSI
•
MR
X
*SUPRASPINATUS RC
SUBSCAPULARIS
AD
RC
*DELTOID
*INFRASPINATUS
AB
X
X
X
Actions at Shoulder Joint: Flexion, Extension, Abduction, Adduction. Medial
Rotation, Lateral Rotation.
Since it is the humerus that moves, all insertions are on humerus.
5 places to insert on the humerus = greater tubricle, lesser tubricle,
intertubercular groove = bicipital groove, medial surface, deltoid tuberosity.
Hint: Concentrate study on the insertions and possible actions at a joint.
You can see the origins more clearly on a chart and answer M-C questions.
RC = Rotator cuff muscle group – very important support in shoulder
(Rotator cuff = 3 muscles found in each fossa of the scapula + teres minor.
The deltoid is a composite muscle that is even antagonistic to itself!
Coracobrachialis
O: corocoid process of scapula I: upper half medial border of humerus
A: flexion, adduction at shoulder
4.Muscles that Move the Shoulder Joint (Humerus)
*Pectoralis major O: clavicle, sternum, upper ribs
I: intertubercular (bicipital) groove of humerus
A: flexion, adduction, medial rotation at shoulder
4.Muscles that Move the Shoulder Joint (Humerus)
*Teres major
O: lateral border of scapula (low)
I: intertubercular (bicipital) groove
A: extension, adduction, medial rotation at
shoulder
Note: look closely at the insertions for
the teres major and teres minor. The
teres major attaches medially and
causes medial rotation. The teres minor
attaches laterally and causes lateral
rotation.
4.Muscles that Move the Shoulder Joint (Humerus)
*Teres minor
O: lateral border of scapula
I: greater tubericle
A: lateral rotation at shoulder
Rotator Cuff Group:
Teres minor
Supraspinatus
Infraspinatus
Subscapularis
4.Muscles that Move the Shoulder Joint (Humerus)
*Deltoid O: clavicle, acromion spine of scapula
Note: origin of deltoid is identical to insertion of trapezius!
I: deltoid tuberosity of humerus
A: flexion, extension, abduction at shoulder
Anterior View
Posterior View
4.Muscles that Move the Shoulder Joint (Humerus)
*Supraspinatus
O: supraspinous fossa
I: greater tubericle
A: abduction at shoulder
The supraspinatus serves to initiate
abduction. The deltoid will aid in
abduction once the arm is partially
raised by the supraspinatus.
Rotator Cuff Group:
Teres minor
Supraspinatus
Infraspinatus
Subscapularis
4.Muscles that Move the Shoulder Joint (Humerus)
*Infraspinatus
O: infraspinous fossa
I: greater tubricle
A: lateral rotation at shoulder
Note: Infraspinatus and teres
minor cross shoulder joint
posteriorly and have common
insertion (greater tubricle) and
are the only lateral rotators.
Rotator Cuff Group:
Teres minor
Supraspinatus
Infraspinatus
Subscapularis
4.Muscles that Move the Shoulder Joint (Humerus)
Latissimus dorsi O: thoracic and lumbar spine, iliac crest, last 4 ribs
I: intertubercular (biciptal groove) A: extends, adducts, medial rotation at shoulder
“Lats” are a prime
mover in adduction
and extension of
shoulder joint. They
are important in
rowing, hammering,
swimming, chopping
wood.
3 powerful muscles
insert in the
intertubercular
groove – latissimus
dorsi, pectoralis
major, and teres
major.
4.Muscles that Move the Shoulder Joint (Humerus)
Subscapularis
O: subscapular fossa medial
border
I: lesser tubricle of humerus
A: medial rotation at shoulder
Note: All medial rotators
(subscapularis, latissimus dorsi,
teres major, pectoralis major)
cross shoulder joint anteriorly
and insert on lesser tubricle or
intertubercular groove.
Rotator Cuff Group:
Teres minor
Supraspinatus
Infraspinatus
Subscapularis
4.Muscles that Move the Shoulder Joint (Humerus)
5. Muscles that Move the Elbow Joint
MUSCLES
F
*TRICEPS BRACHII
E
PR
SUP
X
BRACHIALIS
X
*BICEPS BRACHII
X
BRACHIORADIALIS (Bonus? Yes!)
X
X
• Since these muscles move the elbow joint, the insertions
will be on the ulna or radius, origins are superior to Jt.
• The joint between the humerus and ulna is a hinge, so
muscles that insert on the ulna (triceps brachii,
brachialis) can only cause flexion or extension
– Muscles that cross anterior to the joint cause flexion, those
that cross posterior to the joint cause extension.
• The radius however, is capable of rotation – muscles
that insert on the radius can cause supination or
pronation.
• The biceps brachii inserts on the radial tuberosity of the
radius and causes supination and flexion.
• Prefix brachi refers to humerus.
*Triceps brachii
O: lateral border of scapula,
posterior humerus
I: olecranon process
A: extension at elbow
5. Muscles that Move the Elbow Joint
Brachialis O: anterior lower half of humerus
I: coronoid process A: flexion at elbow
5. Muscles that Move the Elbow Joint
*Biceps brachii O: coracoid process above glenoid cavity I: radial tuberosity
A: flexion at elbow, supination of forearm
Note: one tendon of
biceps brachii in
intertubercular (bicipital)
groove.
5. Muscles that Move the Elbow Joint
Brachioradialis
Origin: distal humerus.
Insertion: styloid process of radius.
Action: flexion at elbow.
Acts best when partially pronated.
Bonus muscle – students
always ask what this muscle
is!
5. Muscles that
Move the Elbow
Joint
6. Muscles of Forearm- Move
Wrist, Hands, Fingers.
MUSCLES
F
E
AB
AD
PR
SUPINATOR
X
PRONATOR TERES
FLEXORS of wrist
EXTENSORS of wrist
SUP
X
X
X
X
X
X
X
• Flexors of wrist include many muscles on anterior side of
forearm.
• Extensors of wrist include many muscles on posterior
side of forearm.
• Abduction of wrist is caused by flexors and extensors on
lateral half of forearm.
• Adduction of wrist is caused by flexors and extensors on
medial half of forearm.
Supinator O: lateral epicondyle
I: radius
A: supination of forearm
6. Muscles of Forearm- Move
Wrist, Hands, Fingers.
Pronator teres
O: humerus head
I: radius
A: pronation of forearm
6. Muscles of ForearmMove Wrist, Hands,
Fingers.
Flexors of Wrist
O: ulna, humerus, radius
I: metacarpals
A: flexion, abduction (lateral side),
adduction (medial side) of wrist
Note: Do not have to know individual
names of flexors or extensors–
Identify only as flexors or extensors
of wrist.
6. Muscles of ForearmMove Wrist, Hands,
Fingers.
6. Muscles of Forearm- Move Wrist,
Hands, Fingers.
Extensors of Wrist O: typically ulna and radius I: metacarpals, carpals, phalanges
A: extension, abduction (lateral side), adduction (medial side) of wrist