MSK non-clinical Flashcards
What is another name for a coronal section?
Frontal section
What is another name for a transverse section?
Axial section
What makes up the axial skeleton?
Skull
Vertebrae
Sternum
Ribs
What makes up the appendicular skeleton?
Upper limb Lower limb Pelvis Scapula Clavicle
Name two dorsal body cavities
Spinal cavity
Cranial cavity
Name 3 ventral body cavities
Thoracic cavity
Abdominal cavity
Pelvic cavity
Is the top of the foot dorsal or ventral?
Dorsal
Is the non-palmar surface of the hand dorsal or ventral?
Dorsal
If someone is lying in a supine position, how are they lying?
Lying face up
If someone is lying in a prone position, how are they lying?
Lying face down
What is a special movement of the shoulder joint?
Circumduction
Describe the movement of the radius during pronation
The radius in the anatomical position is lateral to the ulnar at both the elbow and the wrist. During pronation the distal part of the radius crosses the ulnar superiorly to become medial at the wrist
List the movements that the shoulder can make
Abduction Adduction Extension Flexion Circumduction Medial rotation Lateral rotation
List the movements of the elbow and forearm
Flexion
Extension
Pronation
Supination
List the movements of the hand
Ulnar deviation (adduction)
Radial deviation (abduction)
Flexion
Extension
Describe flexion and extension of the wrist
Flexion is when you decrease the angle between the palmar surface of your hand and anterior forearm. Extension is when you increase that angle
List the movements of the fingers
Abduction
Adduction
Flexion and extension at metocarpalpharyngeal (MCP)
Flexion and extension at interpharngeal joints (PIP) and (DIP)
List the movements of the thumb
Palmar abduction-adduction (same plane)
Flexion-extension-radial abduction (same plane)
Opposition-reposition
List the movements of the hip
Flexion Extension Abduction Adduction Internal rotation External rotation
List the movements of the knee
Flexion
Extension
List the movements of the ankle
Dorsiflexion
Plantarflexion
Inversion - plantar surface faces inwards (more common)
Eversion - plantar surface faces outwards
Which Rami (division of the spinal nerve) forms the brachial plexus?
Anterior Rami
What does the posterior Rami of the spinal nerves innervate at the levels (C5-T1)?
Local structures - does not form part of the brachial plexus
Where in the brachial plexus does the nerves leave the neck and enter the axilla?
Division
What are the cords named in relation to?
Named due to their relation with the axillary artery
What is the apex border of the axillary region?
Lateral border of the first rib
Superior border of the scapula
Posterior clavicle
What is the lateral border of the axillary region?
Intertubecular groove of the humerus
What is the medial border of the axillary region?
Serratus anterior and the thoracic wall (including costal muscles)
What is the anterior border of the axillary region?
Pectoralis major and minor
Subclavius muscle
What is the posterior border of the axillary region?
Subscapularis
Teres Major
Latissimus dorsi
What are the contents of the axilla?
Axillary artery Axillary vein Brachial plexus Axillary lymph nodes Tendons of muscles attaching to the scapula: biceps brachii and coracobrachialis
What would you observe if a patient had damage to their long thoracic nerve and pushed their arms against a wall?
Winging of the scapula due to paralysis of the serratus anterior muscles - these muscles no longer hold the scapula against the ribcage whilst their upper limbs reach anteriorly
What are the embryological derivates of the musculoskeletal system?
Somites and lateral plate mesoderm
What type of mesoderm do somites develop from?
Paraxial mesoderm
In which direction does the development of somites progress?
Cranially to caudally
Where on the body wall do limb buds develop
Ventro-lateral body wall
Which limb bud appears first?
Upper limb - lower limb lags ~2 days behind
When during development do the limb buds appear?
Towards end of fourth week.
Describe the composition of the limb bud when it first appears
Core of proliferating mesenchymal cells with an ectoderm covering
What anatomical axes is the head of the embryo?
Anterior
What anatomical axes is the tail of the embryo?
Posterior
What is the anterior axis called in the embryo?
Ventral
What is the posterior axis called in the embryo?
Dorsal
What mesoderm does the limb buds develop from?
Somatic layer of lateral plate mesoderm
What is the remnant of the notochord?
The nucleus pulposus - it becomes marooned by axial skeleton formation
What does the lateral plate mesoderm (somatic mesoderm) contribute to the limbs?
Limb skeleton
What does the somite mesoderm - which moves into the limb buds - contribute to the limbs?
Musculature
How does the limb bud elongate?
Proliferation of the mesenchyme core
What is the apical ectodermal ridge (AER)?
Thickended ectoderm at the apex of the limb bud. It exerts an influence on the underlying mesenchyme and is responsible for elongation of the limb bud - is a group of organising cells.
What are the three degree of assymmetry of the limb buds?
- proximal-distal axis: shoulder to fingertips
- Dorsal-ventral axis: e.g. no hairy palms
- Anterior-posterior axis: side to side (left and right hands are always mirror images of each other)
What is the role of the AER (apical ectodermal ridge) in limb bud development?
- Critical for limb bud outgrowth
- Orchestrates limb development proximal to distal
- Final stage is appearance of paddles
- Then AER regresses
How is the proximal to distal axis generated?
- AER exerts a diffusion-limited inductive influence on the immediately underlying mesenchyme so it remains undiffferentiated and continues dividing and elongating the limb bud.
- Proximal mesenchyme (free of the inductive influence of the AER) begins to differentiate into constitutive tissues
- Finally AER induces development of the digits within the hand/foot plates
How is dorsoventral patterning of the limb bud achieved?
Ectoderm exerts dorsalising and ventralising influences over the mesenchymal core.
What marks the boundary between the developing dorsal and ventral limb ectoderm?
AER
What does ZPA stand for?
Zone of polarising activity. It is a signalling centre located at the posterior base of the limb bud.