Gross Anatomy 1

anatomical position

A person in the anatomical position: 1. Is standing erect or lying supine (on one's back) as if erect, with head, eyes, and toes directed anteriorly (forward) 2. Has upper limbs by the sides with palms facing anteriorly 3. Has lower limbs together with the feet directed anteriorly

Anatomical planes

Anatomical descriptions are based on four anatomical planes that pass through the body in the anatomical position: 1. Median plane: "midsagittal", "vertical", "longitudinal"; serparates th ebody into left and right and mid section; symmetry is maintained 2. Sagittal planes: also called "parasaggital"; vertical; parallel to median plane 3. Coronal planes: "frontal", vertical, at right angles to median plane; splits body from anterior to posterior 4. Horizontal planes: "transverse", at right angles to the median and coronal planes; splits body from sup to inf

regions of the body

Broad regions will be separated into smaller regions

SERRATUS POSTERIOR INFERIOR

Deep to the lastissimus dorsi. Attaches to the lower 4 ribs. Supplied ventral rami of T9-T11

SERRATUS POSTERIOR SUPERIOR

Deep to the rhomboids. C7, ribs 2-5, ligamentum nuchae. Supplied by ventral rami of C8-T3

Joint Classification (Functional)

FUNCTIONAL: • Based on degree of movement. 1) SYNARTHROSIS: no movement - SUTURE: skull - GOMPHOSIS: cone-shaped peg fits into a socket. E.g. tooth - SYNCHONDROSIS: Cartilaginous joint in which two bones are united either by hyaline cartilage or fibrocartilage, e.g Rib and sternum 2) AMPHIARTHROSIS: slight movement - SYNDESMOSIS: e.g. distal tibiofibular joint - SYMPHYSIS: e.g. pubis 3) DIARTHROSIS: freely moveable with a synovial cavity, articular cartilage and capsule - Ball-and-Socket Joint (spheroid) e.g. hip - Ellipsoidal Joint (condyoid): e.g. carpus - Gliding Joint (arthrodial): tarsus - Hinge Joint (ginglymus) e.g. elbow - Pivot Joint (throchoid) e.g. radioulnar - Saddle Joint ( sellaris) e.g.carpal- metacarpal joint

LUMBAR TRIANGLE (of Petit)

Iliac crest = inferior border Lateral border of latissimus dorsi = medial border Posterior border of external abdominal oblique = lateral border Floor = internal abdominal oblique *It may be a site for abdominal hernias

Intermediate Muscles of back/Intrinsic Muscles: SACROSPINALIS Muscles

Include: Iliocostalis, Longissiumus, and Spinalis • These are three parallel groups or columns called SACROSPINALIS OR ERECTOR SPINAE MUSCLE. • They are all supplied by the dorsal rami of the spinal nerves. • They are named depending on location.

Deep back Muscles/Intrinsic Muscles: TRANSVERSO-SPINALIS MUSCLES

Includes: • Multifidus muscle (most robust in the lumbar region) at the lumbosacral curvature (goes from sacral to cervical region • Interspinalis muscle(b/w the spines) • Intertransversarii muscle (between the transverse processes) • Rotators( transverse process of lower vertebra to spinious process of the vertebra above) -Short (brevis) -Long (longus) • Semispinalis muscle (in the neck region)

SYNOVIAL JOINT

MOST CLASSIC JOINT

Rectus capitis posterior minor (O, I, N, F)

O: Posterior tubercle of atlas I: Nuchal line N: Suboccipital F: Extends and flexes the head laterally

Rectus capitis posterior major (O, I, N, F)

O: Spine of axis(C2) I: Inferior nuchal line N: Suboccipital F: Extends, rotates, and flexes the head laterally

Obliquus capitis inferior (O, I, N, F)

O: Spine of the axis I: Transverse process of atlas N: Suboccipital F: Extends and rotates the head laterally

Obliquus capitis superior (O, I, N, F)

O: Transverse process of atlas I: Nuchal line N: Suboccipital F: Extends, rotates, and flexes the head laterally

Anatomy of a typical vertebra

Pedicle: attaches body to transverse process Lamina: attaches transverse process to spinous process

Joint Classification (structural)

STRUCTURAL • Based on the presence or absence of a joint cavity and the type of C.T. binding the articulating bones. • FIBROUS JOINT: - No joint cavity, fibrous CT - Ex: Distal tibiofibular joint • CARTILAGENOUS JOINT: - No joint cavity, cartilage holds bones together - Ex: Pubis symphysis • SYNOVIAL JOINT: - There is a joint cavity - Bones united by articular capsule(=an envelope surrounding a synovial joint. Each articular/joint capsule has two parts: an outer fibrous layer or membrane, and an inner synovial layer or membrane) and ligaments - Ex: Knee joint, hip joint

Sacrum and coccyx

Sacrum -S1-S5 that are fused together -the most anterior and superior tip (S1) is called the sacral promontory -the anterior wings are called the sacral ala -holes on the lateral sides are called anterior/posterior sacral foramen -the protrubance on the lateral sides are called th lateral sacral crest -Sacral hiatus (opening at the base) is where the spinal nerves exit Coccyx -Co 1-Co 4: 4 fused bones

Circumduction can occur around...

Shoulder joint and Hip joint -its a combination of motion along mutiple axes

Suboccipital triangle (slides 25-28)

The suboccipital triangle is a region at the back of the neck bounded by the suboccipital group of muscles muscles: • Rectus Capitis Posterior Major muscle = forms the medial border • Obliquus Capitis Superior muscle = forms the lateral border • Obliquus Capitis Inferior muscle = forms the inferior border • The roof of the suboccipital triangle is formed by the semispinalis capitis and longissimus capitis muscles • The region has a floor formed by the posterior arch of the atlas and the posterior atlanto-occipital membrane •Contents: Vertebral A and Suboccipital N(C1)

Vertebral column

There are 33 vertebrae: • 7 cervical • 12 thoracic • 5 lumbar • 5 sacral (fused) • 4 coccygeal (fused) Two sets of curvatures: • Primary Curvatures: -They appear during fetal development and are retained in the adult -Thoracic and Sacral regions have this curvature • Secondary Curvatures: -They develop after birth -Cervical and Lumbar regions have this curve *curves occur along saggital plane *there is only one curve in a fetus(primary/concave curvature)

x-ray of cervical vertabrae

in this picture oyu see C2 and C1, the dens, the body of C2, and the transverse pricess of C1 and C2

Anatomy of a typical vertebra pic 2

inferior and superior vertebral notch is where the spinal nerves exits

Zygapophyseal Joints

joint b/w articular processes

Anatomy

the science of the structure and function of the body. It is the study of internal and external structures, and the physical relationships between the various body parts.

Spinal Nerves

• 31 pairs: -8 cervical nerves (7 cervical vertebrae) -12 thoracic nerves -5 lumbar nerves -5 sacral nerves -1 coccygeal nerve (4 coccygeal vertebrae) • Cn1 (suboccipital nerve) between skull and the atlas. • Cn1 has no dorsal root but it has a dorsal ramus. • Cn2-7 exit the vertebral column ABOVE their corresponding vertebrae. • Cn8 passes BELOW C7, between C7 and T1. • All thoracic nerves (Tn1-12) pass BELOW their corresponding vertebral level. • All lumbar nerves (Ln1-5) exit BELOW their corresponding level. • All sacral nerves and coccygeal nerve exit BELOW their corresponding vertebral level.

Joints of the suboccipital triangle

• Atlanto-occipital joint = flexion, extension, and lateral flexion of the head • Atlantoaxial joints = rotation of the atlas and the head as a unit on the axis

Vertebral A

• Branch off the subclavian artery • Travels through the transverse foramina of the upper six cervical vertebrae • Gives off an anterior spinal and two posterior spinal arteries

Coverings of Spinal Cord

• DURA MATER: -Fibrous sheath -Ends at S2 and it becomes filamentous surrounding the filum terminale -The epidural space is between the bone and the dura mater • ARACHNOID MATER: -Ends at S2 -The space between the arachnoid and pia = subarachnoid space (contains the CSF) • PIA MATER: - Closely invests the cord - It has lateral projections between the dorsal and ventral spinal roots = denticulate ligaments - At the conus medullaris it continues as a thread to cover the filum terminale - Therefore, the filum terminale is made up of pia mater from L2-S2, and of pia and dura from S2- coccyx. -The pia ends at L2

Suboccipital nerve (C1)

• Derived from the dorsal ramus of C1 • Emerges between the vertebral artery above and the posterior arch of the atlas below • Supplies the muscles of the suboccipital triangle and the semispinalis capitis muscle

Herniated Intervertebral Disc

• Herniated disc (slipped): -Common between L4- L5, L5-S1, and C6-C7 -The nerve affected is always the one below. E.g. a slipped disc between L4-L5 will affect spinal nerve L5 -when there is too much compression on thw veterbra it cause the nucleus pulposes to get too compressed and ooze out.. it takes the path of least resistance hwich is toward the spinal cord becuase the posterior longitudianl ligament is thinner and weaker than the anterior longitudianl ligament -Dont tend to get herniation in the thoracic region b/c region is more stable therefore less movement

Spinal Cord Position

• In the embryo, the spinal cord extends the entire length of the vertebral column and the spinal nerves pass through the intervertebral foramina at their levels of origin. • The vertebral column and dura mater grow at a faster rate than the spinal cord, therefore the caudal end of the spinal cord terminates at a higher level as development continues; as a result nerves dont exit at same level • During the sixth month of gestation the caudal tip of the spinal cord lies at the level of S1. • At birth, it lies at the level of L3, while in the adults it ends at L1-L2. • As a result of the different rates of growth, the spinal roots run obliquely from the cord to their corresponding vertebral level. • The roots below the caudal end of the cord form a bundle of nerve roots called the cauda equina.

The Spinal Cord

• It is found in the spinal canal. • It is continuous with the brain stem. • The spinal cord is attached to the coccyx at 8 weeks in utero. • In the newborn the spinal cord level is at L3. • In the adult the spinal cord ends at L1-L2, but never below L2. • The conus medullaris ends at L2. • The spinal cord is made up of white and gray matter. • The filum terminale is from L2-Coccygeal

Atlantoaxial dislocation

• May occur from trauma - MVA (rupture of the cruciform ligament) or, from rheumatoid arthritis • May injure spinal cord and medulla • Signs and symptoms may include pain in the posterior neck, and /or painful restricted mobility

LEVATOR SCAPULAE (O, I, N, F)

• O-posterior tubercles of transverse processes of C1- C4 • I-superior angle of the scapula and upper medial border of the scapula • N-C3-C4 • F-elevation of the scapula * Just need to memorize N and F

TRAPEZIUS MUSCLE (O, I, N, F)

• O-spinous process of C1, spinous processes of T1- T12, ligamentum nuchae, superior nuchal line • I-lateral 1/3 of the clavicle, acromion, crest of the scapula • N-accessory spinal (CN XI), and cervical plexus • F-elevates the shoulder(shrugging), pulls the scapula backwards

RHOMBOID MINOR (O, I, N, F)

• O-spinous process of C7, ligamentum nuchae, T1 • I-spine of the scapula • N-dorsal scapular nerve • F-retract and fix the scapula * Just need to memorize N and F

RHOMBOID MAJOR (O, I, N, F)

• O-spinous processes of T2- T5 • I-medial border of scapula • N-dorsal scapular nerve • F-retract and fix the scapula * Just need to memorize N and F

The Back (?)

• The back region extends from the base of the skull to the posterior aspect of the sacrococcygeal column. • Back pain is very common, especially in the cervical and lumbar areas because these regions are highly moveable. • SUPERFICIAL LANDMARKS(bony projections): - A skin dimple associated with the PSIS found on either side of the posterior aspect of the iliac crest (common site for bone marrow biopsy). - Posterior medial furrow. - Erector spinae muscles. - Area of the sacrum.

deep fascia

• The deep fascia is a dense, more organized connective tissue layer that invests deep structures (e.g. muscles). • The deep fascia sends radial projections to deeper structures and bones forming compartments(seperates anterior form posterior -Compartmental syndrome is caused by pressure within the comparments, caused by inflammation, tumor, etc; this build up of pressure will cause neuro-vadcular problem due to the compression of nerves and vessels thus leading to enventual death of muscles, etc do to ischemia etc.

Surface Lines of Skin

• The skin is not smooth. It has a geometric pattern of lines and creases, which follow bundles of collagen fibers in the dermis of the skin. 1. Tension lines, or Langer's lines, or lines of cleavage 2. Friction lines: in palms and soles (finger/foot prints) 3. Flexure lines: over joints

superficial fascia

• The superficial fascia is composed of loose connective tissue and fat. • It is located between the dermis and the overlying (investing) deep fascia. • It contains sweat glands, blood and lymphatic vessels, and cutaneous nerves.

Superficial Muscles of Back

• They connect the upper extremities to the trunk (vertebral column) 1) Lastissimus Dorsi Muscle 2) Trapezius Muscle 3) Levator Scapulae Muscle 4) Rhomboid Minor Muscle 5) Rhomboid Major Muscle 6) Serratus Posterior Superior Muscle 7) Serratus Posterior Inferior Muscle #6 and 7 dont connect back to upper extremeties just back to ribs

Joints of Vertebral Column

•The joints of the vertebral column are held together by: 1. Intervertebral discs: attach body to body 2. Ligaments: makes contact b/w vertebrae stable a. Anterior Longitudinal Ligament: from the anterior tubercle of the atlas to the sacrum; keeps vertebral column form slipping forward(prevents hyperextension); thicker and stronger b. Posterior Longitudinal Ligament: from the occipital bone to the sacrum. Lies within the vertebral canal; thinner, weaker, and narrower; prevents hyperflexion c. Ligamentum Flavum: between the laminae d. Supraspinous Ligament: on top of the spine e. Interspinous Ligament: between the spines(spinous processes) 3. Vertebral arches a. All synovial joints b/w the articular processes b. Zygapophyseal Joints - as a pair, they guide and limit movement of the spinal segment; joints b/w facets 4. Atlanto-occipital joint a. A synovial joint b/w the occipital condyle and C1. Allows nodding and sideways movements 5. Atlanto-axial joint a. Two lateral and one median joint b. The lateral joints are plane and glidding joints, whereas the median joint is a pivot 6. Costo-vertebral joints a. Synovial joints b/w heads of the ribs and vertebral bodies 7. Costo-transverse joints a. B/w the tubercles of the ribs and transverse processes Note: Ribs 1, 10, 11, 12 articulate with one vertebra only

Cervical Vertebrae

-Atlas= C1; has no verterbral body -Axis= C2; has the Dens which articulates with C1 above it -C1-C7 -cervical vetebra have a transverse foramen that is an opening on each of the transverse processes which gives passage to the vertebral artery and vein and a sympathetic nerve plexus. -tranverse processes are not extensive laterally -bifurcation of spinous processes -as you travel from C1-C7 the bodies get larger

Intervertebral Disc

-Fibrous joint between the bodes of the vertebrae, allows for movement -the fibrous part is called the Annulus fibrosus and in the center of that is the Nucleus pulposes(a more gel like substnace that allows the vertebral disc to withstand forces of compression and torsion.)

LONGISSIMUS MUSCLE

-Intermediate of the 3 intrinsic muscles - name varies based on location: Longissiumus Thoracis/Cervicis/Capitis

THORACOLUMBAR FASCIA (lumbodorsal fascia)

-Invests the deep muscles of the back -Provides origins for the latissimus dorsi, internal abdominal oblique, and transversus abdominis muscles

Lumbar Vertebrae

-L1-L5 -Have soild and bulky (thick) bodies and processes -contain sup and inf vertebral notches above and belw the pedicale region.. the superior v. notch of the thoracic v. below and the inf v. notch of the thoracic v. above form a whole for spinal nerves to exit -Secondary curvature

Iliocostalis Muscle

-Most lateral of the 3 intrinsic muscles - name varies based on location: Iliocostalis Lumborum/Thoracis/Cervicis

SPINALIS MUSCLE

-Most medial of the 3 intrinsic muscles - name varies based on location: Spinalis Thoracis/Cervicis/Capitis

Supinaiton and pronation of foot and forearm

-Pronation: rotation of the forearm (or foot) so that in the anatomical position the palm or the sole is facing posteriorly. -Pronation of the forearm is a rotational movement where the hand and upper arm are turned inwards. -Pronation of the foot refers to turning the foot outwards -Supination: of the forearm occurs when the forearm and palm are turned outwards. -Supination of the foot occurs when the sole is turned inwards

Triangle of Auscultation

-Superior border of latissimus dorsi = inferior border -Lateral border of trapezius = medial border -Medial border of scapula = lateral border -Floor = rhomboid major, ICS6

Thoracic Vertebrae

-T1-T12 -Articulate with the head of the ribs at superior demifacet (posterior end of body) and tubercle of the ribs at the facet on the end of the transverse process -Have larger bodies than the cervical v. -spinous process slant downward -transverse and spinous processes are long -contain sup and inf vertebral notches above and belw the pedicale region.. the superior v. notch of the thoracic v. below and the inf v. notch of the thoracic v. above form a whole for spinal nerves to exit

common parts of a vertabrae

-body (anterior) -spinous process(posterior) -Transverse process (lateral) -Lamina(connects tranverse process to spinous process) -Pedicle (connects transverse process to body) -Vertebral foramen (an opeing posterior to body that the spinal cord travels thru)

rib articulation

-ribs 11 and 12 are free floating ribs they dont articulate in the front

Introduction

....

The Back and Spinal Cord

....

3 types of sectionings

1) longitudinal section: seperates hte body from left to right 2)transverse section: serperate the body into inf and superior 3)Oblique section: hybrid

Components of the Occipitoaxial Ligament

1-Cruciform Ligament a-Transverse lig b-Longitudinal lig 2-Apical Ligament 3-Alar Ligament 4-Tectorial Membrane

Key dermatomes

1. T4 = nipple 2. T10 = navel (umbilicus) 3. T12 = above the pubis 4. L5 = hallux (big toe) 5. C7 = middle finger 6. C8 = little finger

Layers of Spinal cord from vertebrae in

1. Vertebral bodies (bone) 2. Epidural space • Fat • Vertebral venous plexus (of Batson) • Spinal nerves 3. Dura mater 4. Subdural space 5. Arachnoid mater 6. Subarachnoid space • Contains the CSF 7. Pia mater 8. Spinal cord

LATISSIMUS DORSI MUSCLE (O, I, N, F)

= Large, triangular muscle which forms, with the teres major muscle, the posterior axillary fold. • O-spinous processes of the lumbar vertebrae, lower 6 thoracic vertebrae, thoracolumbar fascia, iliac crest • I-floor of the bicipital tuberosity of humerus • N-thoracodorsal n. • F-adduction and extension of the UE

Dermatomes

=an area of skin supplied by the sensory fibers of a single dorsal root through the dorsal and ventral rami of its spinal nerve. (look at image on slide 38) -Dermatomes are arranged in a segmental fashion because the thoracoabdominal nerves arise from segments of the spinal cord. -Adjacent dermatomes overlap: Nerves from C4, C5, and C6 will overlap -Physicians need to have a working knowledge of the segmental, or dermatomal innervation of the skin so they can determine (e.g. pain) whether a particular segment of the spinal cord is functioning normally -Do to the overlapping Three contiguous spinal nerves need to be blocked in order to achieve proper anesthesia of the skin segment.

Surface anatomy

=the study of the living body at rest and in action and is used in all three approaches. -The main aim of surface anatomy is the visualization of the structures that lie beneath the skin

Langer's lines

=topological lines drawn on a map of the human body. They correspond to the natural orientation of collagen fibers in the dermis, and are generally parallel to the orientation of the underlying muscle fibers.