Study 3

Question 1

Facts about Bones in the Human Skelton

Answer 1

• 206 bones in the human skeleton.
• Forms the frame of the body and provides protection for organs.
• Provides the framework for soft tissue such as skin and muscles.

Question 2

When bones are fully developed they are composed of three main parts

Answer 2

1) Bones are sheathed by a membrane – the periosteum.
 Where the bony surfaces form joints the protective covering is called articular cartilage
 The periosteum has an outer layer of fibrous tissue and an inner layer of cells called osteoblasts.
 These osteoblasts lay down new bone if it is injured or affected by certain diseases
2) Bones have an outer shell of tissue called compact or cortical bone.
 It consists of tightly packed layers of bony tissue within which are spaces containing blood vessels and nerves.
3) The bone’s inner part is called the medulla.
 Composed of cancellous bone (spongy bone).
 Bone marrow is found in the marrow spaces in the sponge-like bone.

Question 3

Cartilage

Answer 3

A tough nonvascular connective tissue present in joints and certain other body structures.

Question 4

Osteoporosis

Answer 4

– a condition in which bones contain less bone tissue (calcium) than normal bones.
• A disease that results in the decline of bone mass.
• Bones become more brittle and fracture more easily.
• Associated with normal aging.
• Senile osteoporosis – found in the elderly. Leads to painless hip and vertebral multiple wedge-type fractures that cause an abnormal curvature of the spine.
• Kyphosis – an abnormal curvature of the spine
• Post-traumatic osteoporosis – can occur following an injury.

Question 5

Classification of Bones:

Answer 5

1) Long bones
• Found where support and leverage are required
• There is a hollow space in the middle of the medulla called the medullary cavity
• Which is lined by a fibrous membrane called the endosteum.
• Example: leg / thigh bone
2) Short bones
• Found where strength is needed and only limited motion
• Example: arm bones
3) Flat bones
• Used for protection
• Form walls around the viscera – internal organs
• Therefore affording extensive attachments for muscles
• Example: rib cage
4) Irregular bones
• Vertebrae, coccyx, cranium and certain bones of the face

Question 6

Locating Bones:

Answer 6

• Proximal – closer to the torso of the body
• Distal – further away from the torso
• Costal – relationship to the rib
• Dorsal – towards the back surface (posterior)
• Inferior – towards the lower surface
• Superior or Supra – upper or above – top end
• Anterior – nearer the front of the body
• Posterior – nearer the back of the body
• Medial – middle of the body
• Some bones have bumps that are called prominences or processes.

Question 7

Rib Cage:

Answer 7

• Encases and protects the organs of the upper body.
• Thorax – the upper body.
• There are 24 ribs – 12 on each side of the chest connected to the vertebrae of the spine by costal cartilage.
• 14 of the upper true ribs are connected at the front of the chest to the sternum.
• Sternum – a flat and narrow bone linked to the clavicles (collarbones) and the true ribs – also called the breastbone.

Question 8

Shoulder:

Answer 8

• Each shoulder has two bones
• Scapula – also known as the shoulder blade, is a broad flat bone in the upper back.
• Clavicle – also known as the collarbone, is a slender bone in front of the scapular lying very close to the surface of the body at the top of the shoulder.

Question 9

Pelvis:

Answer 9

• A fused bone framework providing protection for lower organs and support of the abdomen.
• Located at the lower border of the trunk and it supports the spinal column.
• Pelvis of the female is broader and flatter than that of the male with a larger central opening to facilitate childbirth.
• Most pelvic injuries heal themselves completely without difficulty

Question 10

3 main parts of the pelvis:

Answer 10

1) Ilia (Ilium) – 2 large wing-shaped bones
• Fracture usually consists of fragments that split off the bone mass
• Normally not a serious injury and usually heals without permanent disability
• The ilium has a cup-shaped depression, the acetabulum, which forms the socket for the femur (leg bone)
2) Ischia (Ischium) – forming loops of bone that extend downward posteriorly from the ilia and bear most of the body weight in a seated position.
• Fracture is usually the result of a blow to the side or the back
3) Pubes (Pubis) – extend in front of the base of the wings of the ilia forming arches above the Ischia
• Fracture is usually the result of a blow to the front.
• The pubic bones articulate in the symphysis pubis, a joint which is composed of fibrocartilage.

Question 11

Arms:

Answer 11

• The arm is made of:
1) Humerus – the long upper arm bone that attaches to the scapula.
 It has prominences called condyles
2) Radius – attached to the lower end of the humerus, extending to the hand in line with the thumb
3) Ulna is also attached to the lower end of the humerus, extending to the hand

Question 12

Hand:

Answer 12

1) Wrist (carpal bones)
 8 carpal bones that make up the wrist
 A break in the carpal scaphoid in the wrist often does not unit properly during the healing process
2) Palm (metacarpal bones)
 5 long cylindrical metacarpal bones that make up the palm
 They join with the carpal bones at the proximal end and with the phalanges at the distal end and where the metacarpal heads form the knuckles
3) Fingers (phalanges)
 Also known as digits
 14 bones – 3 bones (phalanges) in each finger and two phalanges in each thumb

Question 13

Leg:

Answer 13

• The leg, including the thigh (that part =between the knee and the hip) is made up of: femur, patella, tibia and fibula.
1) Femur – extends from the ilium to the knee
 The neck of the femur often does not unite properly in the recovery process
2) Patella – is the knee cap
 A small bone that protects the knee
 Fractures of the patella are most often the result of direct force
3) Tibia – is the shin bone which extends from the femur to the ankle
 It is the larger inner bone
 A fracture on the upper portion of the tibia may result in injury to the knee joint
 This is a serious injury that causes a long disability period
4) Fibula – is connected to the top of the tibia and extends to the ankle on the outside of it
 The long, slender, outer bone of the calf

Question 14

Foot:

Answer 14

• Composed of 26 bones and functions to bear the weight of the body.
1) Ankle – several tarsal bones
2) Instep – 5 metatarsal bones that make up the instep
 Fracture of the slender metatarsal bone is most common
3) Toes – phalanges – make up the toes with 14 bones. Each toe has 3, big toe has 2.
4) Heel – the talus, also known as the astragalus, is the second larges tarsal bone and it supports the tibia and rests on the larges tarsal bone – the calcaneus (also known as the heel bone)

Question 15

Joints:

Answer 15

• Joints are the points at which two or more bones meet or articulate.
• There are movable and immovable joints.
• Immovable joints occur where the bones are in direct contact with one another
1) Hinge joints – found in knees and fingers
2) Pivot joints – found in elbows and the head
3) Ball and socket joints are found in the hip and shoulder

Question 16

Arthritis:

Answer 16

• Arthritis is the inflammation of the joints caused by either non-traumatic or traumatic origins
• The trauma disrupts the smooth movement of the joint by:
• Creating rough surfaces and irritation
• Interrupting the blood supply to the joint
• Interfering with the lubrication of the joint
• Injury the guy wire tendons and muscles which keep the joint in proper alignment

Question 17

Injuries to Extremities:

Answer 17

• Extremities refer to the arms, hands, legs, feet and shoulder
• Following a sprain, fracture or injury to nerves or blood vessels, a condition called reflex sympathetic dystrophy (also called causalgia) may result.
• Symptoms may include pallor, pain, sweating, edema, or skin atrophy

Question 18

Dislocations:

Answer 18

• Dislocation is defined as a disturbance in the normal relationship of the bones which form a joint.
• Subluxation refers to a partial dislocation
• Reduction is the process of realigning bones when a dislocation or fracture occurs
• Adhesion is a fibrous band or structure abnormally uniting parts of the body

Question 19

Hip:

Answer 19

• A hip dislocation occurs when the femur head is pulled from the socket in the ilium and then rammed back causing bone chipping, stretched ligaments and ruptured blood vessels.
• Common hip fractures:
1) Transcervical fracture – passes through the neck of the femur at a slant and it is easily reduced
2) Intertrochanteric fracture – extends across the head of the femur from the greater to the lesser trochanter at the base of the neck of the femur
3) Subtrochanteric fracture – occurs at the high point on the proximal end of the shaft of the femur just below the lesser trochanter

Question 20

Fractures:

Answer 20

1) Simple or closed fracture – the bone does not pierce the skin, so it is not exposed to the air
2) Compound fracture – is exposed to the air, that is, the skin is pierced

Question 21

common fracture patterns

Answer 21

1) Comminuted fracture – a complete break into 3 or more fragments
2) Transverse fracture – a complete break straight across, at right angles to the shaft of the bone
3) Oblique fracture – a complete break diagonally through the shaft of the bone
4) Spiral fracture – a complete break resembling the spiral in a corkscrew
5) Greenstick fracture – an incomplete break that splits in either direction from the break, resembling a break in a green twig
6) Longitudinal fracture – runs from the joint end of the bone towards the midsection
7) Impacted fracture – has the bone forced into itself splintering its midsection

Question 22

• Treatment fractures:

Answer 22

• General anesthesia – patient loses consciousness and the entire body is numb
• Local anesthesia – the patient is conscious and only a particular part of the body is numb
• Open reduction – refers to surgical intervention to bring the bone into proper alignment
• Retention – the process of holding reduced bone in alignment to ensure that proper union occurs
 Splintage – the mechanical means of holding the reduced bone fragments in proper alignment

Question 23

• Imperfect Healing:

Answer 23

• Partial union – occurs when callus does not grow over the entire fracture area
• Fibrous union – the result of callus not hardening
• Mal-union – occurs when fragments unite but the bone does not function normally. The bone may unite with another bone
• Nonunion – occurs when the bone does not heal and the fragments are held together by tissue alone

Question 24

• Fribrosis

Answer 24

is the formation of fibrous tissue

Question 25

Amputation:

Answer 25

Amputation:
• Amputation is the deliberate surgical removal or the accidental cutting off of a body part.
• Septicemia – a disease caused by pathogenic microorganisms invading the body.
• Myoplastic procedure is often used in an amputation to remove circulation in the extreme end of the stump to achieve better muscular control.
• Doctors are faced with difficult decisions to amputate a body part to treat a patient. These situations arise when the body part:
• Is practically severed by an accident
• Is badly mangled with extensive comminuted fractures and lacerations
• Has extensive injury to blood vessels associated with an open joint fracture wound
• Is not responding to treatment to arrest an aggressive destructive infection

Question 26

Trauma During Pregnancy:

Answer 26

• Placenta abruption – the premature detachment of a normally situated placenta often caused by such things as violent labour, disease and chronic nephritis (inflammation of the kidneys)
• Placenta previa – the implantation of the placenta in the lower uterine segment
• Abnormal fetal presentation – or unusual positioning of the fetus could cause abnormal labour
• If an infant is injured while en ventre sa mere (in the womb) he or she is entitled to sue a negligent party for damages that resulted since the live birth.