A&P Chapter 7 Flashcards
How many bones are in the body?
206
What bones are included in the axial skeleton?
The bones of the skull, vertebral column, and rib cage
How many bones are in the axial skeleton?
80
What bones are included in the appendicular skeleton?
The bones of the upper/lower limbs, shoulder, and hip girdle
How many bones are in the appendicular skeleton?
126
What is the most complex bony structure in the body?
The skull
What are the two sets of bones that the skull is formed of?
Cranial and facial bones
What do the cranial bones do for the skull?
Encloses the brain in the cranial cavity and provides the sites of attachment for head and neck muscles
What do the facial bones do for the skull?
Form framework of the face, contains cavities for special sense organs for sight/taste/smell, provides openings for air and food passage, secures teeth, and anchors facial muscles used for facial expression
Most skull bones are flat and firmly locked together, except for what skull bone?
Mandible
Joints in the skull are called _______
Sutures
What is the appearance of sutures?
Serrated, saw tooth appearance
What eight bones is the cranium composed of?
Frontal bone, parietal bone (2), occipital bone, temporal bones (2), sphenoid bone, and ethmoid bone
What are the skull bones to know for this chapter?
Frontal bone, parietal bone, temporal bone, sphenoid bone, ethmoid bone, lacrimal bone, nasal bone, zygomatic bone, maxilla, vomer, inferior nasal concha, sutural bone, and the mandible
The infant skull has ____ bones than the adult skull
More
How are skull bones connected in the infant skull?
Fontanelles
What are fontanelles?
Unossified remnants of fibrous membranes, that allows passage through the birth canal and allows brain growth
What are the four fontanelles?
Anterior, posterior, mastoid, and sphenoidal
Of the four fontanelles, which is the last to close?
Anterior fontanelle
Which tissue type are fontanelles made of?
Dense regular connective tissue
When do fontanelles usually close completely?
The first 2 years
How many bones are in the facial skeleton?
14
How many bones in the facial skeleton are paired?
12
Which bones in the facial skeleton are single?
Mandible and vomer
Which bones in the facial skeleton are paired?
Maxillary, zygomatic, nasal, lacrimal, palatine, and inferior nasal conchae
What bones comprise the facial bones?
Mandible, maxillary, zygomatic, nasal, lacrimal, palatine, vomer, and inferior nasal conchae
What does the hyoid bone provide?
An attachment point for neck muscles that raise and lower the larynx during swallowing and speech
What is special about the hyoid bone?
It’s the only bone of the body that does not articulate directly with another bone
Is the hyoid bone part of the skull?
No
Where is the hyoid bone located?
Lies just inferior to the mandible in the anterior neck
How long is the vertebral column, and how is it broken up?
~28” long, broken into 5 major regions
What are the five major regions of the vertebral column?
Cervical, Thoracic, Lumbar, Sacrum, Coccyx
How many vertebrae are in the cervical spine?
7
How many vertebrae are in the thoracic spine?
12
How many vertebrae are in the lumbar spine?
5
What is the sacrum?
One bone, formed from the fusion of several bones, it articulates with the hip
What is the coccyx?
Fused bones that form terminus of the vertebral column
How many curvatures are in the spine?
4
What does the curvatures of the spine do?
Helps increase resilience and flexibility of the spine
What are the four main curves of the spine?
Cervical, lumbar, thoracic, and sacral
Which two curves in the spine concave posteriorly?
Cervical and lumbar
Which two curves in the spine convex posteriorly?
Thoracic and sacral
Primary curvatures of the thorax and sacrum are convex at what point of time?
Birth
What does the convex curvature of the thorax and sacrum result in?
A C-shaped spine
Secondary curvature of the lumbar and cervical regions convex anteriorly in what point of development?
As the child develops, like when holding up head during tummy time, and crawling
What are intervertebral discs?
Discs between the vertebrae that acts as a shock absorber
What two parts are the intervertebral discs composed of?
Nucleus pulposus and anulus fibrosus
What is the nucleus pulposus and what does it do?
The inner gelatinous nucleus that gives the disc its elasticity and compressibility
What is the anulus fibrosus and what does it do?
The outer collar composed of collagen and fibrocartilage that limits expansion of the nucleus pulposus when compressed
As we age, what happens to the intervertebral discs?
Becomes thin, less hydrated, and less elastic
The risk of what increases as we age?
Disc hernination
How much height loss is common by age 55?
Several centimeters
As we age, what happens to the costal cartilages?
They ossify
What happens when the costal cartilages ossify?
The rigid thorax causes shallow breathing and less efficient gas exchange
All bones lose mass when we age, and the probability of what increases?
Fracture
All vertebrae have a common structural pattern consisting of what?
The body/centrum, vertebral foramen, and intervertebral foramen
What is the body/centrum of the vertabrae?
The anterior weight-bearing region
What is the vertebral foramen of the vertabrae?
Enclosure formed by body and vertebral arch coming together
What is the intervertebral foramen of the vertabrae?
Lateral openings between vertebrae for the passage of spinal nerves
What is C1 considered as?
The atlas
What is special about the Atlas/C1?
It has no body or spinous process
What does the superior surfaces of lateral masses of the Atlas/C1 articulate with?
Occipital condyles, which carry the skull
What movement does the Atlas/C1 provide?
The movement for nodding the head “yes”
What is C2 considered as?
The axis
How can you tell the difference between the cervical vertebrae and the other vertebrae?
The cervical vertebrae has 2 transverse processes, and a bifid spinous process
How can you tell the difference between the thoracic vertebrae and the other vertebrae?
It has a costal facet, which connects to the ribs
Does the Axis/C2 have a body and processes like other vertebrae?
Yes
What is the major feature of the Axis/C2?
A knoblike dens that projects superiorly into the anterior arch of the atlas
The dens is the “______” _____ of the Atlas/C1
“Missing” body
The dens is a pivot for _______
Rotation of the atlas
What movement does the Axis/C2 provide?
Side to side rotation for saying “no”
How many fused vertebrae make up the sacrum?
5 (S1-S5)
What does the sacrum articulate with?
L5 superiorly and with the hip bones
How many fused vertebrae make up the coccyx?
Usually 4, but sometimes 3 or 5
What does the coccyx articulate with?
Superiorly with the sacrum
What is the top part of the sternum called?
Manubrium
What is the tip of the sternum called?
Xiphoid process
What is the thoracic cage composed of?
Thoracic vertebrae, the ribs, sternum, and costal cartilages
What are the functions of the thoracic cage?
Forms a protective cage around the heart, lungs, and great blood vessels, supports the shoulder girdles and upper limbs, provides attachment for many neck, back, chest, and shoulder muscles, and uses intercostal muscles to lift and depress the thorax during breathing
How many bones form the skeletal framework of each upper limb?
30
What bone is in the arm?
Humerus
What two bones are in the forearm?
Radius and ulna
How many carpal bones are in the wrist?
8
How many metacarpal bones are in the palm?
5
How many phalanges are in the fingers?
14
How many bones are in the hand?
27
What is the humerus?
The only bone of the arm
What is the largest and longest bone of the upper limb?
The humerus
What are the features of the humerus, and what is their description?
Head = proximal end that fits into the glenoid cavity of the scapula
Anatomical neck = slight constriction inferior to head
Greater tubercle = separated from the lesser tubercle, and is the sites of attachment of the rotator cuff muscles
Surgical neck = most frequently fractured part of the humerus
Deltoid tuberosity = about midway down the shaft, is the site of deltoid muscle attachment
Medial/Lateral epicondyles = points of muscle attachment
How many vertebrae are in the cervical, thoracic, and lumbar all together?
26
Are the ulna and radius parallel?
Yes
The proximal ends of the radius and ulna articulates with what?
The humerus and each other
The radius and ulna distally articulate with each other at what joint?
Radioulnar
What connects the radius and ulna along their entire length?
Interosseous membrane
What does the thumb/pollex not have?
A middle phalange
Bones of the hand contains what three parts?
Carpals, metacarpals, and phalanges
What is the formation of the carpals?
Eight bones in two rows
What are the carpals collectively known as?
The wrist
What bones are in the proximal row of the carpals, laterally to medially?
Scaphoid, lunate, triquetrum, and pisiform
What bones are in the distal row of the carpals, laterally to medially?
Trapezium, trapezoid, capitate, and hamate
Which carpal bones form the wrist joint?
Scaphoid, lunate, and triquetrum
What is the pelvic girdle formed by?
2 hip bones and the sacrum
What does the pelvic girdle do?
Attaches lower limbs to axial skeleton with strong ligaments, transmits weight of upper body to lower limbs, and supports pelvic organs
What is the mobility of the pelvic girdle in comparison to the shoulder joint?
Less mobility, but more stability
What three fused bones form the coxal bone?
Ilium, ischium, and pubis
What is the deep socket of the pelvic girdle called?
Acetabulum
What is the illium?
Superior region of coxal bone
What does the ilium articulate with?
The auricular surface articulates with the sacrum at the sacroiliac joint
What is the ischium?
Posteroinferior part of the hip bone
What is the pubis?
The anterior portion of the hip bone
Where does the pubis join?
At the pubic symphysis joint
What is the pelvis formed by?
Hip bones, sacrum, and coccyx
What is the difference between the female pelvic and the male pelvis?
The female pelvis tends to be wider, shallower, lighter, and rounder when compared to the male pelvis
Why is the female pelvis wider, shallower, lighter, and rounder than the male pelvis?
It’s adapted for childbearing
What is the pelvic brim/pelvic inlet
Continuous oval ridge that runs from the pubic crest though arcuate line and sacral promontory
What is the false pelvis?
Superior to pelvic brim
What is the true pelvis and what does it define?
Inferior to pelvic brim, defines birth canal
What is the pelvic outlet bounded by?
The pubic arch, ischia, sacrum, and coccyx
The femur is the ______ and ______ bone in the body
Largest and strongest
The femur makes up how much of a person’s height?
One-fourth
The femur is the only bone which what marking?
Trochanter
The leg is made up of two parallel bones, what are they called?
The tibia and fibula
Like the radius and ulna, the tibia and fibula are connected by what membrane?
Interosseous
What is the tibia?
Medial leg bone that receives the weight of the body from the femur
Is the fibula wright bearing?
No
Does the fibula have articulation with the femur?
No
Several muscles originate from which leg bone?
Fibula
The interosseous membrane is a joint that allows what?
Rotation
The fibula articulates proximally and distally which which bone?
Tibia
What is flat foot/pes planus?
Condition that could be congenital or acquired later in life that consists of fallen arches of the feet.
What can flat foot/pes planus be caused by?
Increasing age, obesity, or high-impact activites
How can flat foot/pes planus be prevented?
Wearing proper footwear with good arch support
How are symptoms managed for flat foot/pes planus
Orthotic shoe inserts
What is a bimalleolar fracture?
A break in the distal ends of both the tibia and fibula. It’s a rotational injury and is a common sports injury
What is developmental dysplasia of the hip?
Partial or complete dislocation of the femoral head and poorly developed acetabulum
How often does developmental dysplasia of the hip occur in newborns?
2%
Who is at high risk for developmental dysplasia?
Breech birth babies
What is the treatment for developmental dysplasia of the hip?
Ultrasound of the hips, then harnesses, casting, or surgery
What can unrecognized developmental dysplasia of the hip lead to?
Degenerative arthritis
Median nerves and tendons travel through what?
Carpal tunnel
What is the carpal tunnel formed by?
Ligaments through the wrist
What is carpal tunnel syndrome?
Compressed median nerve which causes tingling and numbness. It can occur from overuse and inflammation of the carpal tendons.
What is a Colles’ fracture?
A break in the distal end of the radius
Why is a Colles’ fracture so common?
Because a person falling attempts to break fall with outstretched hands
Abnormal curvatures can be congenital or result from what?
Disease, poor posture, or unequal pull of muscles on the spine
What is scoliosis?
Abnormal lateral rotation of the spine, most often in thoracic region
What can a lateral rotation of the spine cause?
Breathing difficulties
What is kyphosis?
Abnormal dorsal thoracic curvature
Who is commonly affected by kyphosis?
Osteoporosis, tuberculosis of the spine, rickets, or osteomalacia
What is lordosis?
Accentuated lumbar curvature
What can lordosis be the result of, and who is it seen in?
Can result from disease, but it’s also seen in men with pot bellies and pregnant women
What can severe physical trauma to the spine cause?
One or more herniated discs
What does herniated discs involve
Rupture of the anulus fibrosus
What does the rupture of the anulus fibrosus result in?
Protrusion of nucleus pulposus, which can press on the spinal cord or nerves, causing numbness or excruciating pain
What is the treatment for herniated discs?
Exercise, massage, heat, painkiller, or surgical intervention if non-surgical treatments are not successful
What is the most common congenital abnormality that distorts the skull?
Cleft palate
What is cleft palate?
No medial fusion of right and left halves of palate
The calcaneus and talus are considered what bone type?
Short
What does cleft palate interfere with?
Sucking
