Exam 1: Osteology, Myology, Arthrology Flashcards
1
Q
Long Bones
A
- The length of the bone is greater than its diameter.
- Multiple ossification centers (growth plates)
- EX: locted in the appendages such as humerus, radius, ulna, femure, tibia, fibula, metacarpals/tarsals
2
Q
Anatomy of long bones
A
Note: Metaphyseal growth plate is compromised of cartilage in young animals
3
Q
Short bones
A
- Have approimate equal dimensions (cube shaped)
- EX: carpal bones, sesmoid bones (don’t articulate with other bones)
- Only one ossification center
- NO growth plates
4
Q
Ossification center
A
- Site of earliest bone formation via accumulation of osteoblasts with connective tissue (intramembranous ossification)
- Earliest destruction of cartilage before onset of ossification (endochondral ossification)
5
Q
Flat bones
A
- Present when either extensive protection or attachment area is necessary
- EX: scapula, bones of the skull
- Contain a lot of active red marrow; which is why we take bone marrow bx from these sites
- Diploe: cancellous tissue enclosed by two thin layers of cortical bone (seen in certain areas of the skull)
6
Q
Irregular bones
A
- Can’t be classified under any other category
- Short bones with multiple processes
- EX: vertebrae
- Formed by endochondral ossification (body of bone) and intramembranous ossification (bony processes)
7
Q
Sesamoid bones
A
- Small, seed-like bones that are embedded in muscle tendons
- ALL sesamoid bones are short bones but all short bones are NOT sesamoid bones
- EX: proximal sesamoid bones of the manus and pes, patella (largest)
- Purposes: 1) eliminate tendon shear (occurs when we have sharp angles between bones) 2) redirects lines of force and 3) increases torque
8
Q
Periosteum
A
- Source of osteoblasts (healing fractures)
- Rich in nerves and blood vessels; extremely sensitive
9
Q
Endosteum
A
Lines inner surfce of bone; has similar cell types as in periosteum
10
Q
Medullary cavity
A
Location of bone marrow (red or yellow)
11
Q
Bone development
A
- Most bones form via endochondrial ossification (ossification of a cartilage model)
- Flat bones are formed via intramembranous ossification
12
Q
Chondrodystrophy
A
- Cartilage maldevelopment
- Genetic condition (basset hounds and dauschunds)
- Causes arrested growth of long bones
- Results in disproportionate dwarves
13
Q
Bone blood supply
A
- Nutritional vessels enter the diaphysis and the epiphysis
- Majority of long bones have a single nutrient foramen that accomodates a nutrient artery that enters the bone mid diaphysis
- Periosteal blood vessels supply the outer, cortical bone
14
Q
Wolff’s Law
A
- Normal bone remodels in response to stress placed upon it
- If load on a particular area increases, the bone will remodel to become stronger to resist those forces (muscle building, weight gain)
- Accounts for the variation of bony prominences observed from the specimens in lab
15
Q
Locomotor system (apparatus)
A
- Includes all those structures that provide the body with 1) stability, 2) independent movement; mucles and joints 3) basis for the characteristic conformation of the individual species
- Muscular system: ACTIVE componenet of the locomotor system (skeletal muscles
- Skeletal system: PASSIVE component of the locomotor system (bones and joints)
16
Q
Skeletal muscle components
A
- Epimysium: outermost connective tissue envelope surrounding the muscle bell
- Perimysium: extends from the epimysium into the muscle; divides the muscle into smaller units or muscle fascicles
- Endomysium: extends from perimysium to envelop individual muscle fibers (CELLS)
17
Q
Skeletal muscle diagram
A
18
Q
Tendon of origin
A
- Proximal or central attachment
- May originate from bone, another muscle, or skin (cutaneous muscles)
- Usuall more proximal and or fixed point of muscle attachment
19
Q
Tendon of insertion
A
- Distal or peripheral attachment
- Insertion on bone, another muscle, or skin
- Usually distal or moveable point of muscle attachment
20
Q
Aponeurosis
A
- Sheet like tendon
- Allows muscles to have broader attachment
21
Q
Associated structures that ease the effect of excessive pressure or friction associated with tendons
A
- Sesamoid bones
- Synovial subtendinous bursa : synovial fluid filled bag positioned between a tendon an a bony process
- Synovial sheath: synovial fluid filled bag that wraps around a tendon
22
Q
Muscle fibers parallel to the long axis
A
- Result in strap like muscle
- Greater displacement
- Completed by very short tendons of attachment
- EX: brachiocephalicus
23
Q
Fusiform muscle fibers
A
- Resulting in a spindle-shaped muscle
- EX Biceps brachii
24
Q
Pennate muscle fibers
A
- Fibers that join tendons at an angle
- Pennate, bipennate, multipennate
- “pennatus” = latin for feather
- More fibers = more powerful
- EX: triceps brachii (long head), subscapularis
25
Flat muscle fibers
* Fibers form flat layers ending in broad tendinous sheets
* Aponeuroses
* EX abdominal muscles
26
Multiple heads for muscle fibers
* Muscle arises by two, three, or four heads that merge into one tendon of insertion
* EX: biceps brachii, triceps brachii, and quadriceps femoris
27
Muscle fibers arranged in units
* Two or more fleshy units are separated by an intermediate tendon forming digastric (two bellies) or polygastric units
* EX digastricus, brachiocephalicusm rectus abdominus
28
Muscle fibers arranged in rings
* Muscle fibers are arranged into rings that surround natural openings
* Eye, mouth, anus
* EX: orbicularis oculi, external anal sphincter
29
Fascia
* Allows muscles to function as units
* Divided into superficial and deep
* Superficial: loose connective tissue
* Deep: dense and collagenous tissue from which some muscles may originate or insert; attaches to bones
* Understanding fascial planes is clinically relebant in understanding the spread of infection
30
Muscle fiber arrangement diagram
31
Synarthroses
* Immovable joints
* Includes synostosis
32
Amphiarthroses
* Semimoveable joints
* Includes: suture, syndesmosis, synchondrosis
33
Diarthroses
* Freely moveable joints
* Includes: synovial joints
34
Fibrous joint
* Strong fibrous connective tissues between articulating bones
* Little to no movment
* In some cases bones can fuse resulting in a bony joint (synsotosis)
35
Cartilaginous joint
* Cartilage, either hyaline or fibrocartilage between articulating bones
* Limited movement
36
Synovial joint
* Joint cavity between articulating bones lined with synovial membrane
* Free movement
37
Suture joint
* Seams of bones of the skull (interdigitation)
* Gradually eliminated via ossification (results in synostosis)
38
Gomphosis joint
* Tooth in aveolus, united by peridontal ligament
* Not technically a joint b/c teeth are not considered bones
39
Syndesmosis
* Bones joined by interosseus ligaments (radius/ulna, tibia/fibula)
40
Synchondrosis
* Hyaline cartilage union
* EX costal cartilages connecting ribs to sternum, growth plates
41
Symphysis
* Occurs in the midline of the body where areticulating bones are connected via a flat disc of fibrocartilage
* EX pelvic symphysis, intervertebral discs
42
Synovial joint diagram
43
Acessory structures of the synovial joint
* Meniscus: fibrocartilage located within the synovial cavity; eg in the stifle
* Ligaments: extracapsular ligaments located outside the joint capsule (medial and collateral ligaments
* Intrascapsular ligaments: occur within the joint capsule but are excluded from the synovial joint cavity by folds of synovial membrane (ligament of the femoral head)
* Fat pads: between fibrous and synovial layers, may protrude into a joint cavity (parapatellar fat pads of the stifle joint)
44
Simple joint
* Formed by two bones
* EX: glenohumeral joint
45
Compound joint
* Formed by two or more bones
* Humerotadioulnar joint (elbow)
46
Congruent joint
* Two articular surfaces fir each other
* EX coxofemoral joint (hip)
47
Incongruent joint
* Two articular surfaces do not fit each other
* EX femorotibial joint (stifle)
48
Hinge joint
* Permits angular motion in one plabe
* EX humeroradiounar joint (elbow), metacarpophalangeal joint (fetlock)
49
Spheroidal joint
* Ball and socket
* Permits rotation and other movements
* EX glenohumeral (shoulder) and coxofemoral (hip)
50
Plane A joint
* Permits angular motion in one plane
* EX carpal, tarsal joints, vertebrae (dorsal articulation)
51
Condylar joint
* Formed by two condyles of one bone fitting into concavities of another bone
* EX femorotibial joint (stifle)
52
Pivot joint
* Permits rotation around the longitudinal axis
* EX atlantoaxial joint, radioulnar joint
53
Ellipsoidal joint
* Oval surface nestles within a depression in the opposing surface
* EX temporomandibular joint, antevrachiocarpal joint
54
Saddle joint
* Articular surfaces of two articulating bones are concave
* EX: distal interphalangeal joint
