Skeleton 8

hyoid bone

-"free floating" bone in neck inferior to mandible -only bone in skeleton that does not articulate with any other bone -acts as base for tongue, site of muscle attachments for muscles that move the larynx

true ribs

-1st 7 ribs -attach to sternum by costal cartilages

articular (fibrous) capsule

-2 parts--outer fibrous layer continuous with periosteum, inner synovial membrane that secretes synovial fluid

vertebral column

-26 vertebrae -7 cervical -12 thoracic -5 lumbar -5 sacral (will fuse into 1) -4 coccyx (will fuse into 1)

middle ear cavity

-3 ear ossicles: 1. malleus 2. incus 3. stapes -sound waves cause vibrations of these bones that are transmitted to inner ear (cochlea)

coccyx

-3 to 5 fused vertebrae -"tail bones"

sacrum

-5 fused vertebrae -forms posterior wall of pelvis -ala on lateral sacrum articulate with hip bones to form sacroiliac joints

cervical vertebrae

-C1-C7 -have transverse foramina -articular facets face superior/inferior -bifid (split) spinous processes

fossa (fossae)

-a depression in a bone -ex: mandibular fossa, lacrimal fossa

canal

-a groove or tube-like structure -ex: optic canal

foramen (foramina)

-a hole in the bone (typically for nerves or blood vessels) -ex: foramen magnum, infraorbital foramen

meatus

-a hole or tube-like structure -ex: auditory meatus

interpose group (intrinsic muscles of the hand)

-abducts and adducts digits

latissimus dorsi

-action: adduct, extend, and medially rotate arm -attachments: lower back and humerus

pectoralis major

-action: adducts, flexes, and medially rotates arm -attachments: sternum, clavicle, ribs, and humerus

depressor anguli oris (muscle of facial expression)

-action: depresses the corners of the mouth -"frown" muscle -attachments: mandible and skin of mouth

masseter (muscle of mastication)

-action: elevate and protracts mandible (closes jaw) -strongest muscle of mastication -attachments: zygomatic arch and mandible

rhomboid major and rhomboid minor

-action: elevate and retract the scapula -attachments: vertebrae and medial border of scapula -located deep to trapezius

medial and lateral pterygoids (muscle of mastication)

-action: elevates and protracts mandible (side to side grinding) -attachments: sphenoid and mandible -both pterygoid muscles are deep to masseter -the lateral pterygoid is superficial to the medial pterygoid

temporalis (muscle of mastication)

-action: elevates and retracts mandible (closes jaw) -attachments: lateral cranium and coronoid process of mandible

zygomaticus major (muscle of facial expression)

-action: elevates corners of the mouth -"smile" muscle -attachments: zygomatic bone and skin of mouth

extensor muscles (posterior compartment)

-action: extend wrist and fingers -attachments: humerus lateral epicondyle and forearm, wrist and digits

flexor muscles (anterior compartment)

-action: flex wrist and digits -attachments: humerus medial epicondyle and forearm, wrist and digits

coracobrachilias (anterior compartment of arm)

-action: flexes and adducts the arm -attachments: scapula and humerus

brachialis (anterior compartment of arm)

-action: flexes forearm -attachments: humerus and ulna

brachioradialis (anterior compartment of arm)

-action: flexes forearm -attachments: posterior humerus and radius -primarily located in anterior compartment of forearm but considered part of the arm

rectus abdominis

-action: flexes trunk -attachments: pubis, ribs, and xiphoid process -fibers run superior/inferior -enclosed in the rectus sheath, which is made of the aponeuroses of the other abdominal wall muscles

supraspinatus

-action: initiates abduction of the arm (first 15 degrees) -attachments: supraspinous fossa of scapula, humeral tuberosities

teres minor

-action: laterally rotates arm -attachment: infraspinous fossa of scapula; humeral tuberosities

infraspinatus

-action: laterally rotates arm -attachments: infraspinous fossa of scapula; humeral tuberosities

genioglossus (muscle of tongue)

-action: protracts (protrudes) tongue -attachments: mandible and posterior part of tongue

erector spinae muscles (spinalis, longissimus, iliocostalis)

-actions: 1. bilateral: extend trunk, neck, and head 2. unilateral: laterally flex trunk, neck, and head -attachments: pelvis, ribs, vertebrae, and cranium

sternocleidomastoid muscle (muscle of the neck)

-actions: 1. unilateral (flexes head laterally) 2. bilateral (flexes head/neck towards sternum) -attachments: mastoid processes and clavicle and sternum

deltoid

-actions: abducts (15-90 degrees), flexes, and extends arm; medial and lateral rotation of arm -attachments: scapula, clavicle, and humerus

teres major

-actions: adduct, extend, and medially rotate arm -attachments: scapula and humerus

infrahyoid muscles (muscle of the neck)

-actions: depress hyoid during end of swallowing -attachments: hyoid and sternum -located deep to sternocleidomastoid and below hyoid

suprahyoid muscles (muscle of the neck)

-actions: elevate hyoid during swallowing and speaking -attachments: hyoid, mandible or temporal bone -located above hyoid

trapezius

-actions: elevates, retracts, depresses, and rotates scapula -attachments: C1-T12 vertebrae and scapular spine, clavicle

medial and lateral heads of triceps brachii (posterior compartment of arm)

-actions: extend forearm -attachments: humerus and ulna

long head of triceps brachii

-actions: extends forearm and arm -attachments: scapula and ulna

short head of biceps brachii (anterior compartment of arm)

-actions: flexes and supinates forearm -attachments: scapula and radial tuberosity

long head of biceps brachii (anterior compartment of arm)

-actions: flexes and supinates forearm, flexes arm -attachments: scapula and radial tuberosity

serratus anterior

-actions: protracts and rotates scapula; holds scapula flat against ribcage -attachments: scapula and anterior ribs

iliotibial band (tight band of connective tissue/fascia)

-actions: stabilizes thigh and trunk during walking and running

hinge joints

-allows flexion and extension -ex: elbow joints, interphalangeal joints, knee joints

pivot joints

-allows rotation -ex: proximal radioulnar joints, atlantoaxial joint

plane joint

-allows the articulating bones to glide past each other -you see these joints between the carpal and tarsal bones

condylar joints

-also called condyloid joints -one bone has a convex surface, the other bone has a concave surface -found in the metacarpophalangeal joints (between metacarpals and phalanges; knuckles)

compact bone structure

-an osteon is a structural unit of compact bone -osteons are made up of concentric tubes called lamellae -osteons are oriented parallel to the long axis and main compression stresses -Haversian (central) canal runs through core of each osteon and provides blood supply, nutrients, nerves

ethmoid bone

-anterior to sphenoid bone -takes up most of the area between nasal cavity and the orbits -forms some boundaries of the nasal cavity, also separates nasal cavity from the brain -contains crista galli -contains cribriform plate

glenohumeral joint (shoulder joint)

-articulating bones are the scapula and humerus -ball and socket joint: highly mobile, not stable -dislocates relatively easily

crista galli

-attaches to cribiform plate -separates nasal cavity from brain -site of attachment for dura mater (membrane covering brain)

coracoid process of scapula

-attachment point of the biceps muscle -located anteriorly -acromion articulates with the acromial end of the clavicle (located posteriorly)

vastus lateralis, vastus intermedius (deep to rectus femoris), and vastus medialis

-attachments: femur and tibia via patellar ligament -actions: all vastus muscles will extend leg

gastrocnemius (posterior compartment of leg)

-attachments: femur to calcaneus -action: flexes leg, plantar flexion of foot

flexor hallucis longus (posterior compartment of leg)

-attachments: fibula and hallux -action: plantarflexes hallux and foot -*deep to soleus*

fibularis longus and fibularis brevis (deep to fibularis longus) (lateral compartment of leg)

-attachments: fibula and sole of foot -actions: evert and plantar flex foot

gluteus medius and gluteus minimus

-attachments: ilium and femur -actions: abduction of thigh, stabilization of trunk -both are deep to gluteus maximus -gluteus minimus is *deep* to gluteus medius

iliopsoas (iliacus, soas major)

-attachments: ilium and femur -actions: thigh and trunk flexion (bowing) -easy to see in abdomen; difficult to locate on thigh

tensor fascia lata (muscle)

-attachments: ilium and iliotibial band -action: flexes, abducts, and medially rotates thigh; steadies iliotibial band

sartorius

-attachments: ilium and tibia -actions: flexes, abducts, and laterally rotates thigh and flexes leg -"Tailor's muscle": crosses legs

rectus femoris

-attachments: ilium and tibia via patellar ligament -action: flex thigh and extend leg

gluteus maximus

-attachments: ilium, sacrum, and femur -actions: extension of thigh, lateral rotation of thigh

hamstring muscles

-attachments: ischium and femur, tibia or fibula -actions: extension of thigh, flexion of leg

levator ani

-attachments: ischium and pubis to sacrum and coccyx -support pelvic viscera (organs) -openings for urethra, anus, and vagina

adductor magnus (deep to longus) and adductor longus (medial compartment of thigh)

-attachments: pubis and femur (linea aspera) -action: adducts, medially rotates thigh

gracilis (medial compartment of thigh)

-attachments: pubis and tibia (long, strap-like muscle) -actions: adducts thigh, flexes and medially rotates leg

flexor digitorum longus (posterior compartment of leg)

-attachments: tibia and digits 2-5 -actions: plantarflexes digits 2-5 and foot -*deep to soleus*

tibialis anterior (anterior compartment of leg)

-attachments: tibia and dorm of foot -actions: dorsiflexion, inversion of foot; prevents plantar flexion during walking

soleus (deep to gastrocnemius)

-attachments: tibia and fibula to calcaneus -action: plantar flexes foot

rheumatoid arthritis

-autoimmune disease -symptoms: pain, stiffness, swelling -begins with inflammation of synovial membrane, joint swells -chronic inflammation of the joint capsule deteriorates the connective tissues around the joint

sarcomere

-basic function unit of a skeletal muscle -contraction of the sarcomere is what contracts the muscle -each sarcomere shortens as muscle contracts -the length of a sarcomere goes from Z disc to Z disc -center of the sarcomere is the M line

petrous region of temporal bone

-best seen internally -contains middle and inner ear cavities -petrous = hard

muscles that flex the elbow/forearm

-biceps brachii -brachialis -brachioradialis

tarsals

-body weight mostly carried by talus and calcaneus -talus articulates with tibia and fibula superiorly and calcaneus inferiorly -calcaneus = heel -achilles tendon attaches to posterior surface and enables extension of foot

intramembranous ossification

-bone grows within a membrane -forms many flat bones (bones of the skull-frontal and parietal) as well as maxillae, zygomatic, mandible, and center of clavicle

synchondroses (cartilaginous joints)

-bones joined by hyaline cartilage -ex: costochondral joints, epiphyseal plates

fascicle orientation: convergent

-broad origin -narrow insertion -direction of pull can be changed because different groups of fibers can be activated

lower limbs

-carry entire weight of body -bones are thicker and stronger than upper limbs -femur (thigh bone) is the largest and strongest bone in the body

closure of the epiphyseal plates

-cartilage is gradually replaced by bone tissue on both sides of the epiphyseal plate (primary center of ossification at diaphysis, and secondary centers of ossification in epiphyses) -*when centers of ossification meet (at epiphyseal plate), growth stops*

what is chronic compartment syndrome?

-caused by overuse -resting until it heals is the best course

clavicle

-collarbone -medially, the sternal end attaches to the manubrium of the sternum -laterally, the acromial end articulates with the acromion process of the scapula -function: provides muscle attachments, acts as brace for the scapula and arms -ligaments are quite strong so bone often breaks instead of dislocating

"unhappy triad"

-common injury in athletes -knee is hit from side while foot is planted -result in a combo of multiple torn/damaged ligaments and damage to menisci -ACL, MCL, medial meniscus

cubital fossa

-common location for venipuncture -median cubital vein -located on inside of elbow -ease of access, but variable

flat, irregular, and short bones

-compact bone with periosteum on outside -spongy bone with endosteum inside -contain marrow but don't have a marrow cavity

subdivisions of skeletal muscle

-composed of multiple fascicles which are composed of individual muscle fibers -bundle of muscle fibers--fascicle--bundle of fascicles--muscle

cartilaginous joints

-connected by cartilage tissue -slightly moveable usually -ex: epiphyseal plates (joined by hyaline cartilage)

fibrous joints

-connected by fibrous (CT) tissue -ex: skull sutures -immovable

ulna and radius

-connected by interosseous membrane to keep bones a fixed distance and allow rotation -proximally, radial head articulates with radial notch on ulna -distally, each has a styloid process

femoral triangle (lower limb)

-contains femoral nerve, femoral artery and femoral vein -site for femoral hernias -catheters (i.e. for angioplasty) inserted here -staunch hemmorhage (lower limb) -borders: inguinal ligament (superiorly), sartorius muscle (laterally), and adductor longus (medially)

what are myofibrils?

-contractile portion in muscle fiber -hundreds/thousands of myofibrils in each skeletal muscle fiber -along the length of a myofibril, there are repeating segments called sarcomeres

thoracic vertebrae (T1-T12)

-costal facets for ribs, located on each body of the thoracic vertebrae -articular facets face anterior/posterior -spinous processes are long and project inferiorly

fetal/infant face

-cranium is proportionately huge relative to the face in infancy/early childhood -by age 2, skull is 3/4 adult size -between ages 6-13, face grows outward and develops more "adult" proportions; body size begins to catch up with head

what is compartment syndrome?

-damaged muscle swells, surrounding fascia (inelastic) constricts -puts pressure on vessels and nerves (pain!!), also prevents blood from entering or draining

posterior cruciate ligament (PCL) and anterior cruciate ligament (ACL)

-deep within capsule and cross (cruciate ligament) -connect femur and tibia

transversus abdominis

-deepest abdominal muscle -fibers run horizontally -action: compresses abdominal cavity -attachments: posterior body wall, anterior body wall

muscles that medially rotate the glenohumeral joint

-deltoid -latissimus dorsi -teres major

muscles that flex the glenohumeral joint

-deltoid -pectoralis major -coracobrachialis -biceps brachii

muscles that laterally rotate the glenohumeral joint

-deltoid -teres minor -infraspinatous

muscles that extend the glenohumeral joint

-deltoid -triceps brachii -latissimus dorsi -teres major

axis (C2)

-dens articulates with atlas, allows rotational movement (shaking head "no") -dens used to be the body of the atlas, but not part of axis

internal intercostal muscles (respiratory muscles)

-depress ribs -expiration (forced) -muscle fibers run superomedially (right angles to external intercostals)

what is an insertion?

-distal attachment -bone is mobile

temporomandibular joint (TMJ)

-divided by articular disc (meniscus) into superior and inferior compartments -superior compartment allows gliding -inferior compartment is a hinge joint

atlas (C1)

-does not have a body or a spinous process -articulates with occipital condyles, allows flexion/extension of head (nodding "yes")

metacarpals and phalanges

-each digit has one metacarpal -digits II-V have 3 phalanges: proximal, middle, and distal -digit 1 (pollex) has 2 phalanges: proximal and distal

external intercostal muscles (respiratory muscles)

-elevate ribs -inspiration -muscle fibers run inferomedially between ribs

structure of a long bone

-epiphysis (ends--proximal and distal) -epiphyseal line (growth plate) -diaphysis (shaft) -compact bone (superficial) -spongy bone (deep) -periosteum (sheath on outside of bone) -endosteum (lines internal cavity) -medullary cavity (bone marrow) -nutrient arteries (feed bone) -articular cartilage on ends

lordosis

-excessive curvature of the lumbar spine -usually temporary and resulting from shift for a larger front load -ex: belly in men, pregnant women

kyphosis (dowager's hump)

-excessive curvature of thoracic spine -typically the result of vertebral body factors caused by osteoporosis

tennis elbow (lateral epicondylitis)

-extensor muscles of the forearm attach to the lateral epicondyle of humerus -overuse or trauma

cleft palate

-failure of the 2 sides of the palate to join during development -severity varies -opening between mouth and nasal cavity makes effective nursing difficult -can be repaired surgically with good outcomes

fascicle orientation: parallel

-fascicles run parallel to long axis of muscle -tapered at both ends -strap -high endurance, not very strong though

fascicle orientation: pennate

-fascicles short -attach obliquely to tendon or raphe -uni, bi, multipennate -stronger than parallel muscle of same size

coxal (hip) joint

-femur and os coax -ball and socket joint: less mobility, very stable -deep acetabulum for head of femur -ligamentum teres extends from acetabulum to fovea capitus (on head of femur)--may add stability

external and internal obliques

-fibers run obliquely (same directions as intercostals) -action: flex and rotate trunk -attachments: lower ribs, pelvis, and line alba

symphyses (cartilaginous joints)

-fibrocartilage between articulating bones -ex: intervertebral joints, pubic symphysis

fontanelles

-flexible connective tissue to allow head to deform during birth and allow rapid brain growth -"soft spots" -skull bones will fuse over time

muscles that extend the wrist/digits

-forearm extensors

muscles that flex the wrist/digits

-forearm flexors

nasal bones

-form bridge of nose -attach to cartilages that form nose

facial bone functions

-form framework of face -openings for passage of air and food -hold the teeth -anchor muscles of the face

bones in cranium

-frontal -occipital -sphenoid -ethmoid -2 parietals -2 temporals

frontalis (muscle of facial expression)

-function: raises eyebrows -attachments: frontal bone and epicranial aponeurosis

buccinator (muscle of facial expression)

-function: tightens the cheeks -plays important role in mastication -holds food within the teeth during chewing -attachments: mandible/maxilla and within the skin of face

properties of joints

-functions: support and movement -bones articulate (come in contact) at joints -skeletal muscles CROSS over joints in order to achieve movement -more mobile = less stable -can be classified by function or by structure -joints do have a blood supply and they are innervated too

gluteal region

-gluteal muscles are very thick and have a good blood supply, so good location for intramuscular injections -for IM injections, locate the superior and lateral quadrant -at this location, likely to miss sciatic nerve, other nerves and vessels

head of the ribs

-has 2 facets -one facet articulates with the body of its vertebra -other facet articulates on the body of the vertebra superior to it

cribriform plate

-helps form the roof of nasal cavities -foramina allow passage of olfactory nerves into brain

inguinal hernias

-hernia = protrusion of abdominal viscera through a weakened point in the abdominal wall -most common are inguinal and femoral hernias -an inguinal hernia is a protrusion of the viscera into the inguinal canal, a weak spot where the spermatic cord travels -more common in males, but can happen in females

elbow joint

-hinge joint (humerus/ulna) but annular ligament forms pivot at proximal radioulnar joint -the annular ligament attaches to the ulna medially and laterally, encircling the head of radius

temporal bones

-house opening to ear -form base of cheekbone -3 main regions: petrous, tympanic, and squamous

ilium

-iliac crest is superior ridge of the bone -greater sciatic notch allows passage of sciatic nerve to lower limb

pelvis

-includes both appendicular and axial bones -attaches the lower limbs to the trunk and supports viscera -strong attachment to axial skeleton at the sacroiliac joint (very stable) -less freedom of movement compared to pectoral girdle -"hip bones" + sacrum + coccyx = pelvis

pectoral girdle

-includes left and right scapulae and left and right clavicles -scapulae do NOT join to the axial skeleton at all and their articulation with the clavicle is very loose -they are attached to the axial skeleton by way of associated muscles and ligaments -provides a highly flexible system (lots of movement allowed), but not very stable

thoracic cage

-includes thoracic vertebrae, ribs, sternum, and costal cartilages -protects heart, lungs, other organs -supports pectoral girdle and provides attachment points -intercostal spaces hold muscles that aid in breathing

pelvic outlet

-inferior opening defined by ischial tuberosities -this is the bony feature you sit on -size of this outlet is important for a successful birth

spongy bone (trabecular bone)

-inside bones -better at shock absorption

diaphragm (main muscle of respiration)

-inspiration: diaphragm contracts (depresses) increases size of thoracic cavity -expiration: diaphragm relaxes, thoracic cavity decreases in size -attachments: inside body wall and ribs, central tendon -has hiatuses (openings) for the aorta, inferior vena cava and esophagus

ischium

-ischial tuberosities are the "sit bones"

sphenoid bone

-large and wing shaped -contains sella turcica -only cranial bone that articulates with every other cranial bone

lumbar vertebrae (L1-L5)

-large bodies -articular facets face medial/lateral -short, flat spinous processes

the knee

-largest and most complex joint -usually acts as a hinge but can rotate slightly -bicondyloid (lateral and medial condylar joint)

mandible

-largest, strongest bone in the face -body of mandible contains lower teeth -tooth sockets are on the superior border (alveolar processes) -vessels and nerves enter via mandibular foramen and exit via mental foramen inferior to teeth

fibula

-lateral -head on superior end, lateral malleolus in inferior end (ankle bone) -DOES NOT bear weight -only for stabilization at ankle -does NOT articulate with femur

scoliosis

-lateral curvature of the spine (curved to the side) -usually treated with body braces or surgery when young

muscles that adduct the glenohumeral joint

-latissimus dorsi -teres major

fibrocartilage

-little ground substance -matrix has thick, dense collagen fibers -resists strong compression -found in: intervertebral discs, knee joint, pubic symphysis

radial pulse

-locate anatomic snuffbox (distal to radial styloid process) between tendons for two muscles of the forearm -radial artery travels through this space, so you can palpate pulse here

subscapularis

-located on anterior side of the scapula -action: medially rotates arm -attachment: subscapular fossa of scapula; humeral tuberosities

scapula

-located on posterior surface of rib cage -scapular spine is on the posterior side of scapula -glenoid cavity (glenoid fossa) articulates with humerus (forms the shoulder) -posteriorly, supraspinous and infraspinous fossae are attachment sites for muscles -subscapular fossa is anterior, also site for muscle attachment

cardiac muscle

-located only in heart; pushes blood through circulatory system -striated, Y-shape, involuntary, has intercalated discs

coccygeus

-located posteriorly -attachments: ischium and sacrum -action: supports pelvic viscera

triangle of auscultation

-location on the back with fewer layers of muscles, so easier to hear respiratory sounds with stethoscope -borders: trapezius, rhomboid major, latissimus dorsi

humerus

-longest bone of the upper limb -head articulates with scapula at the glenoid cavity -distal end articulates with radius and ulna (elbow) -greater and lesser tubercles are sites of muscle attachment; deltoid tuberosity is attachment for deltoid muscle -most frequently fractures at surgical neck

menisci of knee

-made of fibrocartilage (aka articular discs) -help even out the weight distribution and stabilize the joint -prevent side to side rocking of the femur on the tibia

bones of the facial skeleton

-mandible -vomer -2 nasals -2 lacrimals -2 maxillae -2 zygomatics -2 palatine bones -2 inferior nasal conchae

sternum

-manubrium -body -xiphoid process -articulates with: clavicles, ribs, and costal cartilages -sternal angle is important landmark for thoracic anatomy

maxilla(e)

-maxillary bones form upper jaw -articulate with all other facial bones except mandible

tibia

-medial -medial and lateral condyles articulate with condyles of femur -diaphysis of tibia is triangular with a sharp anterior border (shin bone) -distal end is flattened for articulation with talus; medial malleolus projects to form ankle bone -articulates with femur at knee and talus at ankle

hyaline cartilage

-most common type of cartilage -tiny, nearly visible collagen fibers called fibrils -found in: ends of long bones, costal cartilages, respiratory structures, fetal skeleton

osteoarthritis

-most common: affects articular cartilages, which break down -"wear and tear" -pain, stiffness, swelling -extreme solution: joint replacement

synovial joints

-most joints are synovial joints -most movable joint type -connected at a joint cavity within a capsule -ex: most joints -freely moveable (diarthroses) -all synovial joints contain a fluid-filled joint cavity

thenar group (intrinsic muscles of hand)

-move thumb -opposes to digits -fleshy part at base of thumb

hypothenar group (intrinsic muscles of the hand)

-moves digit 5 -opposes to thumb

bone tissue

-much more dense than cartilage -very little fluid -resists compression and tension -very strong -well vascularized (heals/remodels easily) -made of organic and inorganic materials -bone is constantly being built up or broken down--growth, strengthening, remodeling, healing, maintenance

muscle attachments

-muscle may attach to bone directly (very short CT, muscle appears fused to bone) or indirectly--muscle attaches to bone by way of CT (tendon or aponeurosis)

male pelvis

-narrower than females -male pelvic inlet is more heart shaped

femur

-neck is weakest part -greater and lesser trochanters are sites of muscle attachments -lateral and medial condyles articulate with the tibia -lateral and medial epicondyles are the more raised parts of these condyles

os coxae (hip bones)

-os coax is composed of 3 bones: ilium, ischium, and pubis (fuse by adulthood) -acetabulum is the lateral socket where the head of the femur articulates (composed of all 3 pelvic bones) -2 hip bones articulate anteriorly at pubic symphysis

appendicular skeleton

-pectoral girdle -upper limbs -pelvic girdle -lower limbs

craniosynostosis

-premature fusion of the skull bones -leads to unusual cranial vault shape

bone development and growth

-process of bone formation is osteogenesis/ossification -begins in the embryo and continues through life (more slowly in the adult) -before week 8, skeleton made of hyaline cartilage or mesenchyme -after week 8, bone tissue begins to replace most cartilage and mesenchyme -ossification may be endochondral or intramembranous

process

-projection from bone, narrow or wide, protrudes from surrounding bone -ex: styloid or mastoid process

cranial bone functions

-protect brain -provide attachment sites for some head/neck muscles

rib cage

-protect internal organs, aid in respiration -12 pairs of ribs -all ribs attached posteriorly to thoracic vertebrae

functions of vertebral column

-protect spinal cord -supports body axis -attachment points for ribs and muscles of neck/back -anchor pectoral and pelvic girdles

what is an origin?

-proximal attachment -bone is fixed

skeletal muscle

-pulls on the bones of the skeleton -striated, voluntary

smooth muscle

-pushes fluids and solids along the digestive tract and regulates the diameters of small arteries -NOT striated, involuntary

osteoporosis

-results from imbalance in normal bone building and degradation cycle -particularly after menopause, women don't absorb as much calcium and so osteoclasts break bone down to release the calcium into the bloodstream

floating ribs

-ribs 11 and 12 -they do not attach anteriorly to the sternum

false ribs

-ribs 8-10 -do not have a direct attachment to the sternum -they attach via a shared costal cartilage

linea aspera of femur

-ridge along the posterior diaphysis of the bone -used for muscle attachment

bursae

-saclike structure with synovial fluid -reduce friction where bones, ligaments and tendons may rub together

carpals (SLTPHCTT anterior view)

-scaphoid (fractured most frequently) -lunate -triquetrum -pisiform -hamate -capitate -trapezoid -trapezium -wrist is very flexible because of the gliding motions at the articulations

patellar surface of femur

-separate condyles anteriorly -patella articulates with femur here

muscles that protract scapula

-serratus anterior

coronoid process of mandible

-serves as an attachment site for the temporalis muscle, a major chewing muscle

patella

-sesamoid bone (formed within connective tissue) enclosed in the tendon of the quadriceps femoris muscles -protects knee joint and improves leverage of the quadriceps muscles -apex is inferior

elastic cartilage

-similar to hyaline but lots of elastic fibers -VERY resilient and flexible; tolerates repeated bending -found in: pinna (outer ear) and epiglottis

what are the parts of skeletal muscle?

-skeletal muscle tissue -connective tissue -nerves -blood vessels

what bones are in the axial skeleton?

-skull, hyoid bone, vertebral column, thoracic cage (sternum/ribs) -80 named bones -function: supports head, neck, and trunk; protects brain, spinal cord, and thoracic organs

compact (cortical) bone

-smooth, dense, external portion of bones -strong, rigid

fascicle orientation: circular

-sphincter -surround external body openings -close when they contract

orbicularis oculi (muscle of facial expression)

-sphincter/circular -closes eyelids -attach to the skin around the eye

orbicularis oris (muscle of facial expression)

-sphincter/circular -puckers/closes lips -attach to the skin around the mouth

cartilage tissue

-structure: avascular (no blood supply) -cell type: chondrocytes (in lacunae) -functions: 1. support soft tissues 2. model for formation of bone 3. gliding surface at articulations ***cartilage is NOT soft bone -3 types: hyaline elastic, fibrocartilage

cranium

-subdivided into vault (calvarium) and the base -vault = superior, lateral and posterior bones of the skull (includes forehead) -base = inferior part of the cranium

the orbit

-supports eyes and muscles that move the eyes -contains fat and lacrimal glands -walls formed by frontal, sphenoid, zygomatic, maxillary, palatine, lacrimal, and ethmoid bones

muscles that abduct the glenohumeral joint

-supraspinatous (0-15 degrees) -deltoid (15-90 degrees)

perimysium

-surrounds each fascicle -divides skeletal muscle into compartments

muscles in the same compartment are often _________

-synergistic (similar actions) -innervated by a single nerve

myofilaments

-thick and thin filaments within a sarcomere -the striations that you see in a skeletal muscle come from the differences in the density and size of the filaments --dark bands: all thick filaments --light bands: all thin filaments

muscles that retract scapula

-trapezius -rhomboid

muscles that elevate the scapula

-trapezius -rhomboid major/minor

muscles that rotate scapula

-trapezius -serratus anterior

muscles that extend the elbow/forearm

-triceps

wrist fractures

-typically fracture distal radius while catching yourself during a fall -common in older females -"dinner fork" presentation -can lead to nerve damage and dysfunction

ankle fractures

-typically result of rolling or twisting -ligaments crossing the joint are often so strong that they remain intact but the bones fracture

distal humerus and elbow

-ulna is the main forearm bone contributing to elbow

curves of the spine

-vertebrae become larger as move inferiorly to support weight -sacrum articulates with hip bones of pelvis, passes weight to appendicular skeleton -curves increase flexibility; also position center of gravity over axis of body

ball and socket joints

-very flexible; allows flexion/extension, adduction/abduction, and rotation -ex: shoulder joints, hip joints

female pelvis

-wider and shallower than males (allows for birth) -pelvic inlet is oval -angle of sacrum and coccyx is wider

tendon sheaths

-wraps around tendons -reduce friction where bones, ligaments and tendons may rub together

what are the 4 skeletal muscle tissue properties?

1. contractility 2. excitability 3. extensibility 4. elasticity

skeletal muscle functions

1. produce movement 2. maintain posture 3. support 4. generate heat 5. storage and movement of materials

endochondral bone ossification

1. skeleton begins as hyaline cartilage model 2. bone replaces cartilage 3. epiphyseal (growth) plates ossify eventually *most of the bones of the skeleton form this way*

what are the functions of the skeletal system?

1. support (entire body) 2. protection (viscera--organs) 3. movement (attachment for muscles, etc) 4. hemopoiesis (blood cell production) 5. energy and mineral reserves (calcium, etc)

fractures of humerus

1. surgical neck 2. midshaft spiral fractures

A pollex has ______ phalanges.

2

How many pairs of ribs are floating ribs that do not articulate with the sternum?

2

each digit of foot has ___ phalanges

3

the foot has ___ metatarsals

5

The skull consists of _____ cranial bones and _____ facial bones.

8 ; 14

A sarcomere is defined as the distance from one _____ to the next adjacent ____ . (The same answer fills in both spaces.)

Z disc

lateral rectus (extrinsic eye muscle)

abducts eye

elasticity

able to return to original length

articular (hyaline) cartilage

absorbs forces on the joint, protects bone

what is acute compartment syndrome?

accident/injury can lead to tissue loss (muscle or limb) due to loss of blood supply

medial rectus (extrinsic eye muscle)

adducts eye

In general, a skeletal muscle is composed of a) Connective tissue sheaths b) Nerves c) Arteries d) Veins e) Muscle fibers

all of the above

pubis

along with ischium, contributes to obturator foramen

muscles in opposite compartments are often _________

antagonistic (opposite actions)

zygomatic processes (part of maxilla)

articulate with zygomatic bone

tubercle of ribs

articulates with a facet on the transverse process of the vertebrae

capitulum of distal humerus

articulates with head of radius

radial head

articulates with the radial notch of the ulna (proximal radioulnar joint) to form a pivot joint

trochlea of humerus

articulates with trochlear notch of ulna

lateral and medial epicondyles on humerus

attachment sites for forearm muscles

The four techniques employed when using surface anatomy for diagnosis are: a) Auscultation b) Percussion c) Nuchal measurements d) Palpation e) Palpebral timing f) Visual inspection

auscultation, percussion, palpation, visual inspection

structural classification of joints

based on connective tissue that binds the bones together (fibers, cartilage) and presence/absence of a joint cavity

sagittal suture

between 2 parietal bones

lambdoid suture

between parietal and occipital bones

muscles that supinate the elbow/forearm

biceps brachii

The principal elbow flexors located on the anterior side of the humerus are the a) Biceps brachii b) Brachialis c) Brachioradialis d) Deltoid e) Trapezius

biceps brachii, brachialis, brachioradialis

the posterior compartment of the thigh consists of the _________, _________, and __________ ("hamstrings")

biceps femoris, semitendinosus, semimembranosus

sella turcica

bony depression that holds the pituitary gland

osteoclasts

break down (consume) bone

osteoblasts

build new bone

what is a fascicle?

bundle of muscle fibers

extensibility

can increase in length

The pubic symphysis is classified as a a) cartilaginous joint and an amphiarthrosis b) fibrous joint and a synarthrosis c) synovial joint and a diarthrosis. d) cartilaginous joint and a synarthrosis. e) fibrous joint and an amphiarthrosis.

cartilaginous joint and an amphiarthrosis

What is the correct order for the vertebral regions, from superior to inferior?

cervical, thoracic, lumbar, sacral, coccygeal

how do you tell the different vertebra apart? (cervical, thoracic, lumbar)

cervical: -split spinous process thoracic: -costal facets (where rib cage articulates with vertebra) -look like the head of a giraffe lumbar: -large bodies -very rounded transverse processes

Which bone is not part of the axial skeleton? a) malleus b) sacrum c) clavicle d) atlas e) frontal bone

clavicle

The only direct connection between the pectoral girdle and the axial skeleton is where the _____ articulates with the _____.

clavicle ; sternum

Patients with osteoporosis often suffer _________ fractures of the vertebral bodies due to loss of bone mass.

compression

The _________ of the mandible articulates with the mandibular fossa of the temporal bone

condyle

temporomandibular joint (jaw joint)

condyle of mandible articulates with temporal bone at mandibular fossa

ligaments

connect bone to bone, strengthen joint. can be internal or external to articular capsule

lateral collateral ligament (LCL)

connects femur and fibula

medial collateral ligament (MCL)

connects tibia and femur

alveolar processes (part of maxilla)

contain teeth

Which are considered specific characteristics of all muscle cells? a) Contractility b) Extensibility c) Excitability d) Elasticity e) Originality

contractility, extensibility, excitability, elasticity

Which is a common site for venipuncture, which is also where one finds the median cubital vein?

cubital fossa

superior oblique (extrinsic eye muscle)

depresses/abducts eye

inferior rectus (extrinsic eye muscle)

depresses/adducts eye

the ___________ is the primary ossification center

diaphysis

the ________ is the secondary ossification center

distal epiphysis

pelvic brim

edge of pelvic inlet

inferior oblique (extrinsic eye muscle)

elevates/abducts eye

superior rectus (extrinsic eye muscle)

elevates/adducts eye

frontal processes (part of maxilla)

extend upward to reach frontal bone

Which elevates the ribs? a) external intercostals b) internal intercostals c) external oblique d) diaphragm e) two of the choices are correct

external intercostals

Pennate muscles resemble a _________

feather

Which triangle is an important arterial pressure point for controlling lower limb hemorrhage?

femoral triangle

coronoid process of ulna

fits into coronoid fossa when forearm bends

olecranon process of ulna

fits into the olecranon fossa of the humerus when forearm extends

trochlear notch of ulna

fits over trochlea to create a hinge

what is an aponeurosis?

flat sheet of tendon

Clenching the fingers to make a fist, then relaxing and straightening them is an example of __________ followed by __________.

flexion ; extension

Your patient is on the tennis team and is suffering from tennis elbow, which affects the muscles that attach to the lateral epicondyle of the humerus. Which group of muscles is affected?

forearm extensors

zygomatic bones

form cheekbones

hard palate

formed by maxillary bones and palatine bone

vomer

forms inferior portion of nasal septum

There are three gluteal muscles. Select the one that is correctly matched with its primary action. a) Gluteus medius: abducts the thigh b) Gluteus maximus: adducts the thigh c) Gluteus minimus: rotates the thigh

gluteus medius: abducts the thigh

Of these muscles, the one not involved in extending the leg is the a) gracilis b) rectus femoris c) vastus lateralis d) vastus medialis e) vastus intermedius

gracilis

A muscle whose name has "triceps" in it

has three muscle heads or tendons of origin.

Which is the most abundant type of cartilage in the body?

hyaline cartilage

When you rest your hands on your hips, just below the waist, you are resting them on the

iliac crests

The most laterally placed of the three erector spinae components is the ______________ group.

iliocostalis

lacrimal bones

lacrimal groove allows tears to drain into nasal cavity

The _______ suture is the articulation between the occipital bone and both parietal bones.

lambdoid

sternal angle

landmark for many things in thoracic cavity/mediastinum (i.e. trachea bifurcates here)

foramen magnum (occipital bone)

large opening in occipital bone that allows the spinal cord to pass and connect with the brain

In anatomic position, the radius lies _____ to the ulna.

lateral

synovial fluid

liquid in joint cavity and cartilages--provides lubrication

auscultation

listen

visual inspection

look at the body

shaft of the rib

main part of the rib (body)

The superior portion of the sternum is called the _________

manubrium

osteocytes

mature bone cells

hallux (big toe) does not have a _____________

middle phalanx

linea alba

midline tendon of the rectus abdominis

contractility

muscle cells can shorten

what do tendons attach?

muscle to bone

The inner, gelatinous region of each intervertebral disc is called the ______

nucleus pulposus

external acoustic meatus (EAM)

opening in the tympanic region leading to the middle and inner ear

Your patient has Bell's palsy, which causes paralysis of the muscles of facial expression. The muscles of mastication are not paralyzed. Which of the following muscles is affected in your patient?

orbicularis oris

Which condition is specifically associated with aging and/or extreme exercise and is commonly called "wear and tear arthritis"?

osteoarthritis

arches of the foot

over time, tendons can begin to fail (under/overuse) which leads to "fallen arches" 1. internal (medial) longitudinal arch 2. transverse (anterior) arch 3. external (lateral) longitudinal arch

xiphoid process

palpate to locate place for chest compressions

An example of a flat bone would be the _______ a) femur b) radius c) trapezoid d) parietal e) calcaneus

parietal

Which is not a function of the vertebral column? a) supporting the weight of the head b) maintaining upright body position c) passageway for cranial nerves d) passageway for spinal nerves e) protecting the spinal cord

passageway for cranial nerves

what bones are in the appendicular skeleton?

pectoral girdle, upper limb, pelvic girdle, lower limbs

pronation of forearm

radius crosses over ulna

supination of forearm

radius is parallel to ulna

A condition in which a portion of the viscera protrudes through a weakened point of the muscular wall of the abdominopelvic cavity is known as a hernia. Which of these muscles might be weak?

rectus abdominis

The most medial of the abdominal muscles are the _________ muscles.

rectus abdominis

Which is not one of the hamstring muscles? a) biceps femoris b) semimembranosus c) rectus femoris d) semitendinosus

rectus femoris

quadriceps femoris consists of ____, _____, _____, and _____

rectus femoris, vastus lateralis, vastus intermedius, and vastus medialis

The _________ is a large, saw-toothed, flat, fan-shaped muscle positioned between the ribs and the scapula.

serratus anterior

deep fascia

sheet of connective tissue that surrounds individual muscles, as well as groups of muscles with same action

If you were to remove the gastrocnemius muscle you would expose the _________

soleus

pelvic inlet

space between pelvic and abdominal cavities (true and false pelves)

joint (articular) cavity

space filled with synovial fluid

This muscle has its origin on the manubrium and sternal end of the clavicle and its insertion on the mastoid process.

sternocleidomastoid

Rotation of the forearm so as to direct the palm anteriorly (as in anatomic position) is called

supination

rotator cuff is composed of _______, ________, _______, ________

supraspinatus, infraspinatus, teres minor, subscapularis

epimysium

surrounds entire "muscle", separates individual muscles

endomysium

surrounds the muscle fibers within a fascicle

Which is not a correct pairing of a bone and its common name? a) clavicle-collar bone b) patella-knee cap c) scapula-shoulder blade d) talus-heel e) tibia-shin

talus-heel

percussion

tap structures to listen for vibrations

Which bone is not part of the facial complex? a) temporal b) mandible c) zygomatic d) maxilla e) nasal

temporal

Four muscles are referred to as rotator cuff muscles. Select the exception. a) supraspinatus b) infraspinatus c) teres major d) teres minor

teres major

occipital condyles (occipital bone)

the region where the skull articulates with the vertebral column

sliding filament mechanism

the thin and thick filaments slide past each other during muscle contraction to shorten the sarcomeres--leads to muscle contraction

neck of the rib

thinner region between the head and tubercle

In which body region would you expect to find a muscle whose name includes the word "pollicis"?

thumb

palpation

touch/pressure

Which is not among the bones in the proximal row of carpals? a) triquetrum b) lunate c) scaphoid d) trapezoid e) pisiform

trapezoid

rotator cuff muscle injuries

usually supraspinatus is injured

squamous portion of temporal bone

vertical portion (part of cranial vault)

excitability

very responsive

surface anatomy examination involves ________, ________, _________, ________

visual inspection, percussion, palpation, auscultation

mandibular symphysis (not visible)

where the 2 halves of the body of mandible join to form the chin (aka mental protuberance)

suprasternal angle

where trunk meets neck