Locomotion and Musculoskeletal

Question 1

Major 6 key topics of MUSCULOSKELETAL SYSTEM?

Answer 1

Respiration, Communication, Support/Protection, Flight, Feeding, Abdominal Press (female animals key)

Question 2

7 Components of system and their main function?

Answer 2

1. Bones (osteology) - props
2. Joints (arthrology) - allows movement between bones
3. Ligaments - holds bones together
4. Skeletal Muscles (myology) - produces movement between bones across joints
5. Tendons - attach muscles to bone across joints
6. Nerve supply - control of movement
7. Blood supply - metabolic support

Question 3

Parts of the Axial and Appendicular skeleton?

Answer 3

Skull -> vertebral column -> ribcage -> sternum
Forelimb -> Hindlimb

Question 4

Regions of the vertebral column?

Answer 4

Cervical, Thoracic, Lumbar, Sacral, Caudal
(CTLSC)

Question 5

3 Main Axial joints? (dog example)

Answer 5

Occipito-atlanto-axial complex
Intervertebral
Lumbosacral

Question 6

Forelimb Bones and Joints? (Top to bottom order)

Answer 6

Bones:
Scapula, Humerus, Radius, Ulna, Carpal, Metacarpal, Phalanges (proximal, middle, distal)
Joints:
Shoulder(after Scapula), Elbow(after Humerus), Carpus, Metacarpophalangeal(fetlock), Proximal interphalangeal, distal interphalangeal

Question 7

Hindlimb Bones and Joints?

Answer 7

Bones:
Pelvis (both for axial and appendicular skeleton), Femur(after Hip), Fibula, Tibia, Tarsal (ankles), Metatarsal, Phalanges (proximal, middle, distal)
Joints:
Sacroiliac (fixed for propulsion of hindlimbs), Hip, Stifle(after Femur), Tarsus/hock, Metatarso-phalangeal(fetlock), Proximal interphalangeal, distal interphalangeal

Question 8

5 Bone Classifications? (surface texture, shape, etc)

Answer 8

FLAT (scapula, pelvis, skull bones)
-Large SA for muscle attachment
-Protects underlying structures

LONG (humerus, femur)
-Support and leverage in limbs

SHORT (carpus/tarsus)
-Large range of movement
-Anti-concussive (not easily shattered from damage)

SESAMOID (patella/kneecap)
-Embedded in tendons
-Changes angle in bony surface (redirection of forces)
-Reduces friction (damage prevention)

IRREGULAR (vertebrae)
-Midline/Axial location and unique

Question 9

3 Bone Surface features?

Answer 9

ROUGH - covered by periosteum, area for general muscle attachment.

BONY BUMPS - provide specific sites for attachment of important structures like; tuberosities, tubers, tubercles, trochanters, and processes.

SMOOTH - articular/ joint surfaces, covered by hyaline cartilage.

Question 10

4 Bone Developments?

Answer 10

INTRAmembranous ossification: directly from foetal connective tissue (embryonic).

ENDOchondral oss. :from cartilage precursor (comes before smth), mineralises in sections, centres of oss, growth plates between centres to allow growth. (elongation of bone, matrix of cartilage)

CORTEX: wall (bone marrow/blood vessel)

MEDULLARY cavity: hollow centre.

Radiography (x-ray): bone = white/radio-opaque, growth plate = dark/radio-lucent.

Question 11

3 Types of Joint and their features?

Answer 11

FIBROUS (skull, radius & ulna)
-little movement
-bones joined by dense conjunctive tissue

CARTILAGENOUS (pelvic, mandibular/lower jaw)
-flexibility
-joined by cartilage for slight movement

SYNOVIAL (elbow, stifle)
-large range of move
-two articulating bones joined my fluid-filled space (named joint cavity)

Question 12

5 features of Synovial joints?

Answer 12

1. Hyaline Cartilage - covers articular surface
2. Synovial Fluid - lubricates (no pain no blood supply)
3. Synovial membrane - produces the fluid
4. Joint Capsule - fibrous layer outside membrane
5. Collateral ligaments - located medially and laterally (to prevent wrong movement)

Question 13

The main joints and ligaments located in Elbow and Shoulder/Hip?

Answer 13

Elbow:
-collateral ligaments
-interlocking bones
-limited range of motion
-“hinge” joint

Shoulder/Hip:
-ball & socket joints
-no collateral
-large range of motion
-stability comes from surrounding muscle

Question 14

Skeletal Muscle - Structure and Function?

Answer 14

Structure:
-fibres arranged in parallel bundles
-attached to rigid structures
-origin (proximal/start)
-insertion (distal/end)

Function:
-muscle fibres contract
-sites of attachment pulled closer together
-effect dependent on location of origin & insertion

ANTAGONISTIC PAIRS = opposite action
(one goes short while other is long, and vice versa).

Question 15

4 Muscle groups?

Answer 15

Epaxial - dorsal to vertebral column

Hypaxial - ventral to vertebral column

Trunk * torso muscles

Extrinsic - origin axial & insertion appendicular skeletons, move limb relative to trunk.

Intrinsic - origin & insertion and movement within limb.

Question 16

4 Limb movements?

Answer 16

Flexion:
-folding of limb

Extension:
-stretching of limb

Protraction:
-forward
-e.g jaw moves forward, chin sticks out

Retraction:
-backward
-e.g shoulders going back causes chest to push forward

Question 17

What and where are Tendons?

Answer 17

They are a continuation of muscle as fibrous cords:
-less bulky across joints, allowing flexion
-small area of attachment

Located in distal limbs and shoulder joints.

Question 18

What is a Stifle joint?
How does it look?
Where is it?
What function?

Answer 18

A hinge joint, called FEMUR and TIBIA, connects hip and knee to ankle.
-located between femoral and tibial condyles (rounded projections of a bone)
- Meniscus
-has C shape wedges of cartilage
-attached to tibia by collateral ligaments
-cranial and caudal cruciate(cross-shaped) ligaments
-movement occurs between femur & meniscus
-resists rotation
-long digital extensor muscle