Skeletal System Flashcards
(109 cards)
1
Q
TUBEROSITY/TROCHANTER/TUBERCLE
A
PROTUBERANCES ON BONES, WHICH ARE USUALLY FOR THE ATTACHMENT OF MUSCLES
2
Q
TROCHLEA
A
BONY STRUCTURES THROUGH OR OVER WHICH TENDONS PASS. THEY ARE USUALLY GROOVES IN THE BONE
3
Q
CONDYLE
A
A ROUNDED PROJECTION ON A BONE, USUALLY FOR ARTICULATION WITH ANOTHER BONE
4
Q
EPICONDYLE
A
A PROJECTION OF THE BONE ON THE LATERAL EDGE ABOVE ITS CONDYLE
5
Q
FORAMEN
A
AN OPENING OR PASSAGE INTO OR THROUGH A BONE E.G. TO ALLOW THE PASSAGE OF BLOOD VESSELS AND NERVES
6
Q
FOSSA
A
A HOLLOW OR DEPRESSED AREA ON A BONE
7
Q
TENDON
A
ATTACHES MUSCLE TO BONE
8
Q
LIGAMENT
A
ATTACHES BONE TO BONE
9
Q
What are the functions of the skeleton?
A
- Support and Protection (soft tissues and organs within)
- Articulations (permit movement via muscles)
- Storage (stores essential calcium and phosphate)
- Haemopoiesis (manufactures blood cells in red bone marrow)
10
Q
What makes up the axial skeleton?
A
Skull Vertebral Column Sternum Ribs Mandible
11
Q
Describe the make up of the vertebral column
A
Cervical (7), thoracic (13), lumbar (7), sacral (3 fused together) and coccygeal (about 20 - depends on breed)
12
Q
What does the appendicular skeleton consist of?
A
Scapula, Pelvis and the Limbs
13
Q
What is the make up of the Splanchnic skeleton? Give examples
A
Composed of bones that are not attached to the rest of the skeleton. E.g. Os Penis and Fabellae (sesamoid bone behind the stifle)
14
Q
What is a sesamoid bone and give an example
A
A bone that develops within a tendon or a ligament. E.g. patella. They serve to change the angle at which the tendon passes over the bone and reduces wear and tear.
15
Q
Name the 2 methods of bone development and what bones are formed by each
A
- Intramembranous (Flat bones are formed this way)
2. Endochondral/ Interchondral (Long bones)
16
Q
Describe the process of intramembranous ossification
A
The osteoblasts lay down new bone between the 2 layers of fibrous connective tissue. There is no cartilage template. Osteoblasts convert soluble salts of magnesium and calcium into insoluble salts such as calcium phosphate.
17
Q
When does an osteoblast become an osteocyte?
A
When the osteoblast becomes surrounded by bone matrix.
18
Q
What are osteoprogenitor cells?
A
They are mitotic cells that divide into 2 daughter cells. The are responsible for maintaining the population of osteoblasts.
19
Q
What is an osteoclast responsible for and where is it found?
A
It is responsible for destroying or remodelling bone and is found in the Haversian Canal
20
Q
What is endochondral ossification?
A
Involves the replacement of a hyaline cartilage model by bone i.e. the cartilage becomes calcified and is replaced by bone. The process starts in the developing embryo but is not completed fully until the animal reaches maturity and growth is ceased.
21
Q
Describe the steps of endochondral ossification
A
- Cartilage model exists in the embryo
- Ossification begins in the diaphysis (shaft) in the primary ossification centre. The cartilage is replaced as the osteoblasts lay down bone , which gradually extends towards the ends of the bone.
- Secondary ossification then begins in the epiphysis
- Osteoclasts start to remove bone from the centre of diaphysis in to form the marrow cavity, whilst the osteoblasts continue to lay down new bone at the outer edges.
- The first growth plate fuses and marrow cavity extends
- Proximal growth plate fuses and growth ceases
22
Q
What is the growth plate and why does it exist?
A
A band of cartilage between the epiphysis and diaphysis. Allows the bone to lengthen whilst the animal is growing, once it reaches its final size it ‘closes’ and is replaced by bone.
23
Q
What type of tissue is bone? What are the two types of bone?
A
Connective Tissue
- Compact Bone 2. Spongy/Cancellous Bone
24
Q
Where is compact bone found?
A
On outer surfaces of bones
25
Describe the structure of Compact Bone
Made up of Haversian Canal Systems (contain blood vessels, lymphatics and nerves).
Surrounded by plates of bone called Lamellae. The spaces between the lamellae are called lacunae (contain osteocytes and lymph).
Canaliculi are fine channels between the lacunae and Haversian canals - they carry lymph.
26
Describe what makes up Compact Bone Tissue?
Calcium, Collagen Fibres, Osteocytes and mucopolysaccharides (ground substance)
27
What covers all bones?
A tough, fibrous membrane called Periosteum - it helps provide blood to the bone and is very sensitive to pain
28
What is the nutrient foramen?
A small opening in the cortex in the shaft of long bones. Where blood vessels enter and nutrients are supplied
29
What are articular bone irregularities? Give an example
Smooth projections of bone where joints are formed. E.g. Head of femur fits into acetabulum of pelvis to form hip joint
E.g. trochlea of humerus fits into the trochlear notch of the ulna
30
What are non-articular bone irregularities? Give an example
Rough projections where muscles and ligaments attach. (The stronger the muscle, the larger and rougher the projection)
E.g. Anconeal process of the Ulna
which sits within the olecranon fossa when the elbow is extended)
31
Describe the structure of spongy/cancellous bone?
Haversian systems are spread more widely and the spaces between are filled with Red bone marrow (fat and blood cells). Found where mechanical stress is low e.g. at the ends of long bones
32
What 3 parts is the skull made up of?
The cranium, the maxilla and the mandible
33
What is the cranium?
The caudal part of the skull which provides the bony 'case' in which the brain sits.
34
What bones make up the base of the brain box?
One behind the other at the midline of the skull - the sphenoid bone (closer to nose) and occipital bone (forms framework around the foramen magnum)
35
What is the foramen magnum?
A hole in the bony skull where the muscles that support the head and neck attach and where the spinal cord passes through
36
Where does the 1st cervical vertebrae (the atlas) join the skull?
At the occipital condyles
37
What bone protects the tympanic bulla? What is the tympanic bulla?
Temporal Bone. A small bony chamber that contains the middle ear - the exit from the tympanic bulla to the external ear is the external auditory meatus
38
What does the sphenoid bone join with (apart from the occipital bone)?
Sphenoid bone is continued on either side nearer the nose by a frontal bone
39
What is the ethmoid bone? What passes through it?
A sieve-like bone which separates the cranial cavity of the nose from the cranium. The olfactory nerve passes through its perforations.
40
What makes up the maxilla?
The Nasal chambers, lacrimal bone and zygomatic bones
41
What separates the nasal cavity?
Nasal septum which attaches to the middle of the ethmoid bone
42
What forms the walls of the nasal cavity?
Incisive bone, nasal bone, maxilla, palatine bone and ethmoid bone
43
What are turbinates?
Tiny, thin scrolls of bone that are attached to inside walls of nasal cavity
44
What is the correct name for the 'cheekbone'?
The zygomatic arch
45
Where are the eyes found in terms of the skull bones?
In the Orbits
46
Where do the right and left mandibles meet?
The mandibular symphysis - a point of weakness
47
Where do the teeth fit into?
The horizontal ramus of the mandible
48
How is the mandible attached to the skull?
By muscles that attach from the skull to the vertical ramus (process) of the mandible
49
What are the 2 processes of the vertical ramus of the mandible?
1. The Coronoid process
- point of attachment for some jaw muscles
2. Condyloid process
- Articulates with the temporal bone
50
Where does the Hyoid apparatus hang down from and what does it attach to?
What is the correct name for the Adam's Apple?
Hangs down from the Tympanic Bone
Attaches to tongue and larynx
Laryngeal Prominence
51
What are the two types of teeth dogs and cats have?
Deciduous (milk or baby teeth) and Permanent (adult teeth)
52
What is the main difference between deciduous and permanent teeth?
Deciduous teeth are whiter and smaller and fall out as the permanent teeth erupt
53
What are the holes in the bones where the teeth sit in?
Sockets called alveoli
54
Describe the structure of the teeth
Inner pulp cavity (contains blood vessels and nerves) leads down to a root canal.
Surrounded by Dentine.
The top part exposed In the mouth is then covered in a very hard layer called the enamel.
Under the gum-line, the dentine is surrounded by the periodontal ligament and then cement attaches this layer to the bone.
55
Name and describe the 4 teeth types
1. Incissors
- at front of mouth
- small and pointed
- have a single root
2. Canines
- on each side of the incisors
- long and sharp
- have a single root
3. Pre-molars
- flatter surface with several (2-4) cusps
- 2 or 3 roots to give stability
4. Molars
- Same as pre-molars, but large
- 3 roots
56
What are carnassials?
Last upper pre-molar (dog 4th and cat 3rd)
First lower molar
Important teeth in cutting through tough material
57
When do dogs and cats lose their baby teeth
4-5 months old - starting at the incisors and working caudally
58
Describe the dental formula for deciduous teeth
Dog: 3/3 1/1 3/3 =28
Cat: 3/3 1/1 3/2 =26
59
Describe the dental formula of Permanent Teeth
Dog: 3/3 1/1 4/4 2/3 = 42
Cat: 3/3 1/1 3/2 1/1 =30
60
Name and describe the 3 dog skull shapes
1. Doliocephalic
- dogs with long, thin head and muzzle
e. g. greyhound
2. Mesocephalic
- dogs with a medium length head and muzzle
e. g. spaniel
3. Brachycephalic
- short head and muzzle (therefore short nasal chambers and mandible)
e. g. French bulldog, pug
61
What are the differences between dog and cat skulls?
Cat skulls are much shorter and lack the muzzle
Cats have a much larger orbit
Cat skull more rounded
62
Name the 3 types of joints
1. Fixed/Synarthrosis/Fibrous
2. Cartilaginous/Slight moveable
3. Synovial/Diarthrosis
63
What are fixed/synarthosis/fibrous joints?
2 bones meet and are only separated by a tiny band of fibrous tissue. These joints are generally immoveable.
e.g. found in sutures of the skull e.g. teeth in alveoli
64
What are cartilaginous joints?
Where 2 bones are covered with hyaline cartilage and are connected by a pad of fibrocartilage and ligaments. There is not a complete capsule around the joint. There is limited movement.
65
What are the 2 types of cartilaginous joints?
Synarthrosis
- cartilaginous joints allowing little or no movement
e. g. pubic symphysis
Amphiarthrosis
- cartilaginous joints allowing a reasonable degree of movement
e. g. intervertebral discs
66
Describe a synovial joint
They facilitate a wide range of movement and are generally located at the ends of long bones.
2 or more bones where the end of the bones are covered in hyaline cartilage. Between the two hyaline cartilage layers is the synovial fluid. It is surrounded by a fibrous membrane. The entire gap between the bones is then surrounded by a joint capsule. The bones are also connected by ligaments. In some synovial joints, the cavity may be divided by an articular disc or a meniscus.
67
What Is the function of synovial fluid?
Provides nutrients to the articulating cartilage, carries waste products and lubricates the joint.
68
Give an example of a synovial joint
Stifle Joint - has a meniscus, bones connected by patellar ligament (connects patella to tibia) and cruciate ligaments (connects femur to tibia - also known as intracapsular ligament).
69
Name and describe the types of synovial joints and give an example
1. Hinge Joint
- allows movement in 1 direction
e. g. flexion and extension of elbow joint, stifle joint
2. Pivot Joint
- allows one rotation
e. g. radius and ulna at elbow joint, allows turning of the carpus
3. Condylar Joint
- allows flexion and extension to a straight line and then overextension
e. g. hock (tarsus) and carpus
4. Ball and Socket (universal)
- Allows great range of movement
e. g. shoulder (head of humerus sits in glenoid cavity of the scapula)
5. Plane Joint
- Gliding movement of one bony surface over another
- restricted by ligaments and bony prominences
e. g. joints between rows of carpal and tarsal bones
70
Name some joint movements
Gliding, rotation, circumduction, angular (flexion and extension), abduction/adduction
71
What type of joints link the vertebral column?
Cartilaginous, amphiarthrosis joints
72
What is the function of the vertebral column?
Supports the trunk, appendicular skeleton and protects the spinal cord
73
What is the name of the first and second vertebrae?
C1 -Atlas
| C2 -Axis
74
Describe the structure of the intervertebral discs
Inner, soft centre called Nucleus Pulposus
| Outer, fibrous layer called Annulus fibrosus
75
Describe the structure of Vertebrae
Tall spinous process that projects dorsally. 2 transverse processes that project laterally. Cranial and caudal articular surfaces that form the synovial joints with adjacent vertebrae. Vertebral foramen allows nerves and blood vessels to pass from spinal cord to the rest of the body.
76
What holds the intervertebral discs in place?
Dorsal longitudinal ligament and Ventral longitudinal ligament
77
Describe the structure of the atlas
Flattened, very large transverse process
Large vertebral foramen
No/ very small spinous process
No body
78
Describe the structure of the Axis
Elongated spinous process
Has long body with cranially projection process called the dens or odontoid peg
Has a strong ligament called nuchal ligament (extends to T1)
79
Describe the structure of the thoracic vertebrae
Tall spinous process
Short bodies
The height of the spinous process decreases towards the lumbar veterbrae
80
What two attachments do thoracic vertebrae have?
The costal fovea - forms a synovial joint with the head of the rib
The transverse fovea - forms a synovial joint with the tubercle of the rib
81
Describe the structure of the Lumbar vertebrae
Large Bodies
| Long, large transverse processes
82
Describe the structure of the ribs
Partly bone and partly cartilage (costochondral)
Long, arched bones which connect dorsally to the vertebrae.
The inside of the ribs lack a medullary cavity, the inside is filled with spongy bone, packed with red bone marrow
83
Where does the rib attach to the vertebral column?
2 points:
Capitulum - to body of vertebrae
Tuberculum - to the transverse process of the vertebrae
84
How many ribs are there?
13
There are 9 'true ribs' that articulate with the sternum and vertebral column, ribs 10-12 are false ribs which don't join directly to sternum, but join to each other. The 13th rib is a floating rib - only connected dorsally
85
Describe the structure of the sternum
8 sternebrae
1st sternebrae is called the Manubrium
8th sternebrae is called the Xiphoid Process
86
What are the 2 types of girdle
Pelvic and Pectoral
87
What makes up the pectoral girdle?
Scapulae (2) and Clavicles (2)
88
Describe the scapula
Triangular shaped bone
It has a raised spine on outer surface with supraspinous fossa on one side and infraspinous fossa on the other
At the end of the spine there is a projection called the acromion where muscles attach.
The bony articulation with the humerus is the glenoid cavity
89
Is there a bony connection between the forelimb and the trunk? What hold it in place?
NO
| Held in place by a synsarcosis joint
90
Do dogs and cats have a clavicle?
Dogs no longer possess it. They have a vestigial clavicle 'clavicular intersection' - a small tendinous band embedded in the brachiocephalic muscle near the point in the shoulder.
Cats have a much reduced clavicle but is still visible on an x-ray.
91
Describe the location of the clavicle
Membranous, slightly curved rods of bone suspended in ligaments and muscles between the scapulae
92
Describe the structure of the pelvis
Two symmetrical bones joined at the pubic symphysis. Each pelvic bone is composed of 4 fused bones: pubis, ischium, ilium and acetabulum. The head of the femur is held in a ball and socket joint by the teres round ligament in the acetabulum of the pelvis. The iliac bones have long processes which articulate with the sacrum at the iliosacral joint.
The obturator foramen is the hole in which blood vessels and nerves pass from the pelvic cavity to the hindlimbs
93
Name the forelimb bones from proximal to distal
```
Scapula
Humerus
Ulna
Radius
Carpus
Metacarpus
The phalanges
```
94
Describe the humerus
Long bone
Head of humerus proximally articulates with the glenoid cavity of the scapula
Olecranon fossa articulates distally with the anconeal process of the ulna.
95
Describe the Ulna and Radius
Both are long bones
The anconeal process of the ulna articulates with the olecranon process of the humerus proximally
The radius is a simple bone that lies on top of the ulna at the elbow joint
96
Describe the carpus
At the carpus, the ulna lies lateral and the radius lies medial. The styloid process of both lie on either side of the first row of carpal bones. There are 7 carpal bones in two rows.
The first row is composed of the radial carpal bone (which articulates proximally with the radius) and the ulnar carpal bones (which articulates proximally with the ulna) and the accessory carpal bone which projects caudally (from the palmar surface).
Distally, the first row of carpal bones articulate with the second. The second row articulate with each other also.
97
Describe the Metacarpus
Composed of five small long bones.
The first metacarpal bone is much smaller and makes up the dew claw.
The metacarpal bones articulate proximally with the carpal bones and distally with the phalanges
98
Describe the phalanges
Long Bones
Each digit has 3 phalanges, except digit 1 (the dew claw) which only has 2.
The proximal phalanx articulates with the metacarpal bone above. The medial with the one above and below. The distal phalanx ends in the ungual process which forms part of the claw
99
What are found behind the metacarpo-phalangeal joints and the distal inter-phalangeal joints?
Pairs of sesamoid bones
100
Describe the Femur
Long Bone
Head of femur sits within the acetabulum of the pelvis and is held in place by the teres or round ligament.
At the distal end are the condyles which articulate with the tibia at the stifle joint
101
Describe the patella
Sesamoid Bone
Runs between the condyles of the femur in the trochlea groove.
Found with the tendon of the quadriceps femoris
102
What ligaments stabilise the stifle joint?
The cruciate ligaments (2)
- run between the femur and the tibia
- intra-articular and cross within the joint
- prevent bones sliding back and forwards
The collateral ligaments (2)
-run on medial and lateral side of the joint
103
What fibrocartilage is found within the stifle joint?
The menisci (2)
- fibrocartilage pads
- cushion the bone
- increase area for articulation
104
What are the fabellae?
2 sesamoid bones found behind the stifle in the gastrocnemius muscle origin. They articulate with the condyles of the femur.
105
Describe the Tibia and Fibula
The tibia is larger and lies medial to the fibula.
| On the proximal tibia there is the tibial crest where the quadriceps femoris muscle attaches.
106
Describe the tarsus
Made up of 7 bones in 3 rows.
The first row is composed of 2 bones: the talus (tibial tarsal bone) and the calcaneus (fibular tarsal bone) which articulate with the tibia and fibula at the hock joint. The calcaneus is lateral and has a large caudal projection known as the tuber calcis which forms the point of the hock. The hock is the point of attachment for the achilles tendon
107
Describe the metatarsus and phalanges
Same structure as metacarpus and phalanges except most lack a digit 1 (dew claw)
108
What causes the sphlanchnic skeleton?
Bone develops within the muscle and is not attached to the main skeleton
109
What is the os penis?
A sphlanchnic bone. Found in penis of cats and dogs. It has a groove the surrounds the urethra.
In dogs, the groove lies ventral to the urethra; in cats the groove lies dorsal to the urethra.
