Chapter 2 Flashcards
Function of the musculoskeletal system?
- Protects vital organs
- Support posture
- Stores fuels, fats and minerals
- Allows movement
- Blood cell production
- Heat
Superior
Closer to the head than another part
Inferior
Cloister to the feet than another part
Anterior/Ventral
Towards the front of the body
Posterior/dorsal
Towards the backside of the body
Medial
Towards the imaginary midline of the body
Lateral
Alway from the imaginary midline of the body
Proximal
A body part closer to it’s point of attachment
Origin
Muscle’s attachment in which that bone remains immobile for an action
Insertion
Muscle’s attachment that is on the bone that my moves during an action
Distal
A body part further away from the point of attachment than another
Left (body)
Towards the left side of the body
Right (body)
Towards the right side of the body
Superficial
A body part closer to the surface of the body than another
Deep
A body part that is internal or further away from the surface of the body than another
Palmar
The palm side of the hand
Plantar
The sole side of the foot
How many bones are in the skeleton?
206 bones
What sections make up the Axial Skeleton?
- Skull (Cranium)
- Sternum
- Rib cage
- Vertebral column
- Sacrum
What sections make up the Appendicular skeleton?
- Arms
- Legs
- Hips
- Shoulder
Axial Skeleton (Function)
Provide the main support of the body
Appendicular Skeleton (Function)
Made of limbs and girdles that connect to axial skeleton
What are the sections of the Vertebral Column and in what order?
- Cervical Vertebral
- Thoracic Vertebral
- Lumbar Vertebral
- Sacrum
- Coccyx
Number of unfused Cervical Vertebrae bones?
7
Number of unfused Thoracic Vertebrae bones?
12
Number of unfused Lumbar Vertebrae bones?
5
Number of FUSED Sacrum Vertebrae bones?
5
Number of FUSED Coccyx Vertebrae bones?
4
Joint
Where two or more bones meet
What joint allows no movement?
Fixed/Fibrous joint
What joint allows slight movement?
Cartilaginous joint
What joint allows free movement?
Synovial joint
Synovial Joint (consists of)
- synovial capsule
- collagenous material
- synovia membrane
- synovial fluid
What are the 6 types of synovial joints?
- gliding
- saddle
- condyloid
- pivot
- ball and socket
- hinge
Gliding joint (example)
Flat bones glide past each other in a biaxial manner. E.g. Carpals joint
Condyloid joint (example)
Similar to hinge joint but allows rotation(biaxial). E.g. Wrist joint
Pivot joint (example)
A uniaxial joint that allows only rotation. E.g. Atlanto-axis joint in neck
Saddle joint (example)
Where concave and convex bones align generally biaxial. E.g. Carpo-metacarpal joint of thumb
Hinge Joint (example)
A uniaxial joint. E.g. Elbow joint
Ball and socket (example)
A rounded bone head articulates with a cup-shaped cavity. E.g. Shoulder joint
Flexion
Angle decrease between articulating bones
Extension
Angle increasing between articulating bones
Abduction
Body part moving away from the midline of the body
Adduction
Body part moving towards the midline of the body
Rotation
A bone turned on it’s axis can be medial or lateral rotation.
Circumduction
None moving in circular fashion generally possible in ball and socket joint.
Supination
Palm up
Pronation
Palm down
Dorsiflexion
Toes up
Plantarflexion
Toes down
Inversion
Sole inward
Eversion
Sole outward
Tendons
Muscle to bone
Ligament
Bone to bone
Muscles (Functions)
- Posture
- Essential body function
- Movement
Reciprocal inhibition
muscles working in teams, agonists contracts while antagonists relaxes
Agonist
Muscle that causes the action (prime mover)
Antagonist
Muscle that lengthens and relaxes to allow movement to occur
Stabilisers
Muscle that stabilise one part of body while other part is moving
What are the 4 muscle fibre arrangements?
- Circular
- Convergent
- Pennate
- Fusiform
Circular muscle fibre
Arranged in rings. E.g. Eyes and mouth
Convergent muscle fibre
Broad origin then converge, triangular in appearance. E.g. Pectoralis major
Pennate muscle fibre
Muscle fibres are short and attach to central tendon that runs the length of the muscle, high strength and power. E.g. Deltoid, Quadriceps
Fusiform muscle fibre
Muscle fibres run the same direction as tendons, low force but high mobility. E.g. Hamstrings and biceps brachii
Muscle fibre arrangement
Thousands of muscle fibres arranged into bundles called fasciculi
Stages from nerve impulse to muscle action
- Brian initiates a message
- Nerve impulse go down spinal cord and to motor nerve
- Message passed to Motor neurons
- Message branches off to all muscle fibres controlled by that nerve
Motor unit (consists?)
+ Motor unit recruitment
Consists of one motor neuron and the muscle fibres that it stimulates
Fine movements use motor units connected to less muscle fibres
Gross movement may use motor units with thousands of fibres.
All or nothing principle
When an electrical impulse reaches a certain threshold all fibres of that motor unit will contract simultaneously.
Muscle fibre types
- Slow twitch fibres (oxidative)
- Fast twitch - 2A (oxidative)
- 2B (glycolic)
Isoinertial contraction
Resistance/load remains constant
Isometric contraction
Force is developed but there is no change in length of muscle
Isokinetic contraction
Muscle contracts maximally through whole range of motion, uses special equipment.
