Flashcards in MSK Deck (226)
What is the most common site of fracture of the humerus?
Name the anatomical landmarks of the humerus
-Head, anatomical neck, surgical neck
-Greater tubercle, lesser tubercle, intertubecular groove
-Deltoid tuberosity, radial groove
-Lateral epicondyle, medial epicondyle, olecranon fossa, capitulum (radius), trochlea (ulna)
Name the anatomical landmarks of the radius
Name the anatomical landmarks of the ulna
-Ulnar styloid process
Name the carpals of the hand
What are the 3 defining features of a synovial joint? What disease affects these?
-Articular capsule (synovium)
Give 3 causes of hypotonia
-Primary degeneration of muscles (myopathies)
-Loss of sensory afferents from muscle spindle
Explain the processes which occur at a NMJ
-AP arrives at end plate causing influx of Ca
-Causing binding of vesicles containing neurotransmitter to fuse with pre-synaptic membrane via synaptotagmin
-2 molecules of Ach bind to 1 nicotinic receptor
-Opening of Na channels
What is unfused and fused tetanus? State a disease which is linked to this
-Unfused tetanus is a series of action potentials causing muscle twitching in which muscles have time to relax before next ap delivered
-Fused tetanus is when the ap are delivered at a frequency which does not allow the muscle fibre to relax and sustained contraction occurs.
-Clostridium tetani produces a toxin causing tetanis carachterised by painful muscle spasms
What are the nerve roots of the brachial plexus and where do they emerge?
-C5-c8 above c5-t1 vertebrae and t1 below t1
name the 5 branches of the brachial plexus and the nerve roots of each
Briefly describe development of the limbs
-limb buds elongate and develop thickened ridge distally known as apical ectodermal ridge
-AER drives elongation and prevents differentiation by releasing signalling molecules
- The proximal portion of the limb buds are too far away to be influenced so begin differentiating whilst the distal keeps elongating
-AER begins to regress except for primordia of digits.
-Interdigital spaces undergo apoptosis and elongation of fingers occurs
-Mesenchyme turns to cartilaginous model and endochondral ossification occurs
What is the zone of proliferating activity in the developing limb buds
-Area which controls dorsal-ventral patterning
What is a dermatome? Demonstrate them on the upper and lower limb
-Strip of skin supplied by a single spinal nerve
What nerve innervates trapezius?
Describe the different muscles whcih abduct the arm and their associated degrees
-Supraspinatus -> 0-15
-Deltoid -> 15-90
-Trapezius -> 90+
What nerve supplies the deltoid and why is examination of the deltoid particularly relevant?
-Loss of sensation over regimental badge shows damage to axillary nerve
-Biggest muscle group in arm so wasting is easily visible
Name the muscles of the rotator cuff and state its main function
-Stabilise the soulder joint
What factors make the shoulder joint unstable? In which direction is it most likely to dislocate? What local structures are most at risk of damage
-Shallow glenoid cavity
-Disproportionate articular surfaces
-Anterior inferior from an abducted position
-Rotator cuff, axillary nerve
What is the coracoacromial arch and its clinical significance
-Made be coracoid process, acromion and coaracoacromial ligament
-prevents upper dislocation of humerous
-Painful arc syndrome -> supraspinatus tendon inpingement under CAA -> irritation and inflammation producing pain on abduction between 50-130 degrees
Give risk factors for painful arc syndrome
-Repetitive use -> racquet sports or occupation involving arms over head
What are bursae? List the diseases you know involving bursae
-Synovial membrane-lined sacs filled with synovium to facillitate movements of tendons and muscles over bone by reducing friction
-Bakers cyst -> popliteal bursitis
-Housemades knee -> infrapatella bursitis
-Clergymens knee -> pre-patella bursitis
-Painful arc -> subacromial bursitis
Which movements flex, extend, abduct and adduct the shoulder?
-Flexion -> pec major, coracobrachialis, biceps brachii, anterior deltoid
-Extension -> posterior deltoid, lat dorsi, teres major
-ABduction -> supraspinatus, deltoid, trapazius, serratus anterior
-ADduction -> lat dorsi, pec majr and teres major
Which arteries supply the glenohumeral joint?
-Anterior and posterior circumflex
Which muscles does musculocutaneous innervate and what are their actions
-Biceps brachi -> flexion of elbow and shoulder, and main supinator
-Brachialis -> flexion of elbow
-Coracobrachialis -> shoulder flexion, medial rotation
Which muscles does radial nerve innervate in the arm and what are their functions?
-Triceps brachii -> extension
What nerves supplies the anterior forearm?
-Ulnar nerve supplies FCU and medial half of FDP
-Median nerve serves the rest
What are the muscles of the anterior forearm?
-4 superficial =Pronator teres, Flexi Carpi Radialis, Palmaris longus, Flexi carpi ulnaris
-4 Deep = Flexor digitorum superficialis, Flexor digitorum profundus, Flexor pollicis longus, pronator quadratus
What are the functions of FCR?
-Flexion of the wrist
-Abduction of the hand (radial deviation)