Introduction to the MSK System Flashcards
Axial skeleton
bones of the skull, neck and trunk
Appendicular skeleton
Bones of the pectoral and pelvic girdles, bones of the lower and upper limbs
Upper limbs
1 long bone in arm - humerus
2 long bones in forearm - radius and ulna
Hand: carpal bones → metacarpals → phalanges
Lower limbs
1 long bone in thigh - femur
2 long bones in leg - tibia and fibula
Foot: tarsal bones → metatarsals → phalanges
Bony feature
functional hole, bump or groove found on bone which develops during bone growth
How are bony features made?
Adjacent structure applies force to bone, moulding its shape OR adjacent structure develops at the same time as bone and the bone has to grow around the other structure - forms a foramen
Tuberosity
rough area of bone where muscles attach e.g. ischial tuberosity
Bone
hard, connective tissue
Cartilage
less rigid than bone
located where mobility is required - articulations
3 types of joint
synovial, cartilaginous and fibrous
What compromise do joints make?
compromise between mobility and stability - the more mobile a joint, the more easily it is dislocated
Joints have an excellent supply of what?
Sensory nerve supply
Where is skeletal muscle usually found?
Deep to deep fascia
Skeletal muscle attachments to bone
Usually 2 points of attachment to bone - ‘origin’ (usually most proximal part) and ‘insertion’ on the other side
What happens during skeletal muscle contraction?
The origin and insertion are moved close together, muscle fibres shorten along the long axis
Tendon
attach muscle (usually) to bone
Aponeurosis
Flattened tendon
Most commonly associated with flat muscles
Attach muscle to soft tissue
Biceps brachii (attachments)
Long head originates from the supraglenoid tubercle of the scapula
Short head originates from the coracoid process of the scapula
Both heads insert distally into the radial tuberosity and the fascia of the forearm via the bicipital aponeurosis
Biceps brachii (innervation)
musculocutaneous nerve
Biceps brachii (actions)
supination of the forearm (spans proximal radioulner joint anteriorly) and flexion of the shoulder and elbow joint (spans shoulder and elbow joint anteriorly)
Deltoid muscle (attachments)
originates from the lateral third of the clavicle, the acromion and the spine of the scapula, attaches to the deltoid tuberosity on the lateral aspect of the humerus
Deltoid muscle (innervation)
axillary nerve
Deltoid muscle (actions)
Anterior fibres: flexion and medial rotation of the shoulder
Posterior fibres: extension and lateral rotation of the shoulder
Middle fibres: the major abductor of the arm
Reflexes are…
protective and automatic