Title:
URL Source: blob://pdf/b89d995a-b340-4ca8-85b0-4b3ac35f1214
Markdown Content: Illustration Courtesy of Essential Clinical Anatomy, Grays and Netters .
Dr. Joy Y. Balta
Introduction &
Superficial Back
Muscles Outline
2
Introduction to the course
Organization of the nervous
system Joints and the
Intervertebral discs
Muscles of the back
-Extrinsic Classes
3
Lectures posted online - asynchronous
Lab Sessions:
Fridays, PM
Access to the dissection lab - use
to your advantage ! General Information
4
Read your handbook
Email access and announcements on Canvas
Keep up with your classes
Attendance is compulsory
Sign and turn in certificate of compliance before the first
practical
Staff
*Email is the best way to contact A
Lab rules
5
Appropriate and professional behavior at all times
Scrubs (BYOS) and closed shoes/boots must be worn
Gloves must be worn
mask s, face shields, and protective eyewear as needed
No mobile phones in DR
Contact lenses?
Expected Pregnancy
Do I really need to say no food or drink in the DR? (this includes chewing gum)
Tidy table and use spray
No paper towels or gloves in tissue tub
Dont move tissue between tables
Wash hands and dissection tools at the end of each session Organization of the Nervous
System
6
nerves are spreading around the body
going towards PNS * going away from PNS
What is inside
going on
the body
around us
*Signal starts inside the * sensory input from parts
spinal cord of the body that we are
to the origin of the * making a decision to execute
spinal cord a function
and the lower part of
the spinal cord A not voluntary ,
not
to the affected organ (heart rate , digestion) Formation of a Spinal Nerve
Posterior (dorsal) root
Anterior (ventral) root
Spinal n.
Posterior (dorsal) primary rami
Anterior (ventral) primary rami
7
Dermatomes vs. Myotomes
Area of skin supplied
by single nerve or
spinal cord level
Region of skeletal
muscle innervated by a
single nerve or spinal cord
level
8
Typical dermatome map
Sensory innervation
*provide sensory input from the skin on the surface to the inside of the
body
AReferred pain
Clinical Correlate: Herpes Zoster
Reactivation of previous infection of dorsal root ganglia or sensory ganglion
Vesicular rash confined to radicular or cranial nerve sensory distribution
Sites affected: one or several contiguous unilateral dermatomes, CN V, or CNVII sensory
distribution(s) 9Functions:
The Back
10
holding head up
*There will be minor differences in diagrams/labeling depending on
What textbook you use so try to use slide diagrams Surface Anatomy
11
Acromion process
Position of the external important to create a line
occipital protuberance 3 for the suboccipital triangle
and the muscles of that
region
Spine of scapula
medial border of scapula
inferior angle of the scapula
iliac crest
posterior superior iliac spine Vertebral Column Level Corresponding structure
C2-3 Mandible
C3 Hyoid bone
C4-5 Thyroid cartilage
C6 Cricoid cartilage
C7 Vertebra prominens
T3 Spine of scapula
T8 Level that IVC pierces diaphragm
T10 Xiphisternal junction
T10 Level that esophagus pierces diaphragm
T12 Level that aorta pierces diaphragm
L1 End of spinal cord (conus modullaris)
L3 Subcostal plane
L3-4 Umbilicus
L4 Bifurcation of aorta
L4 Iliac crests
S2 End of dural sac 12
Abnormal Curvatures
Kyphosis Lordosis Scoliosis
13 Movement of the Spine
14
tilting your body sideways
moving from side to side
moving backward
moving forward Muscles of the Back
15
Extrinsic: migrated from ventral surface of the body & carried innervation with them
-Superficial Extrinsic Muscles: connect to appendicular skeleton
-Intermediate Extrinsic Muscles: attached to ribs and act as respiratory muscles
Intrinsic: originated developmentally in the dorsum of the back & remained true or intrinsic
First layer
Second layer
Third layer
*divided into superficial and intermediate Scapulothoracic Movements
16
*No joint between the scapula and thorac it is just held together by muscles
bringing your
shoulder a
I
bringing
you r
shoulder
backwards 17
Superficial Extrinsic Muscles
Trapezius Latissimus dorsi
Origin Medial 1/3 sup.
nuchal line, nuchal
lig, Occp. Pro., Sp.
Processes C7-T12
Sp. Processes T7- L5,
Thoracolumbar
Fascia, Iliac crest
lower 3/4 ribs
Insertion Lat. Clavicle,
acromion and
spine of scapula
Edge of bicipital
groove of humerus
Function U: elevate, M:
retract, L: depress
Extends, adducts,
medially rotates
Innervation Spinal Accessory
(XI) & C3-C4
Thoracodorsal nerve
(C6-8)
Trapeziu s Accessory nerve
Latissimus dorsi
Thoracolumbar fascia
body and usually more stable
(T) (t)
Aproximal T U X M*Distal L moves arm away or closer L L
U=upper ,M=middle , L=lower cranial nerve #
1
8
Superficial Extrinsic Muscles
Rhomboid Ma. Rhomboid Mi. Levator Scap.
Origin Sp. processes T2-
5
Nuchal ligament,
Sp. processes
C7,T1
Tubercles
transverse
processes C1-4
Insertion Medial border
scapula (spine
inf. Angle)
Medial end
Scapular spine
Medial
border above
spine
Function Retract (adducts)
and elevate
scapula
Retract (adducts)
and elevate
scapula
Elevates
scapula
Innervation Dorsal
Scapular n. (C4,C5)
Dorsal
Scapular n.
(C4,C5)
Cervical
nerves C3, 4
and Dorsal
Scapular n.
(C5)
L. S.
R. Minor R. Major Innervation & Blood Supply of Levator Scapulae &
Rhomboids
19
Superficial Back Muscles
20
Triangle of
Auscultation
Lumbar
Triangle
Boundaries:
Superior =
Trapezius
m.
Inferior = Latissimus
dorsi m.
Lateral = Rhomboid
major m.
Floor (deep) = 6th
intercostal space
21
Boundaries:
Medial = Latissimus
dorsi m.
Lateral = External
oblique m.
Inferior = Iliac crest
Floor (deep) =
Internal oblique m.
Triangles of the Back