ubital Fossa & Vessels
This aponeurosis provides protection to neurovascular structures within the cubital fossa and tenses with biceps activation
What is the bicipital aponeurosis?
At the proximal radioulnar joint, the head of the radius rotates within this osseous structure.
What is the radial notch of the ulna?
This nerve traverses the carpal tunnel and is compressed in carpal tunnel syndrome.
What is the median nerve?
Translate 'flexor carpi radialis' into its action and anatomical attachment.
It flexes the wrist (carpi) on the radial side (radialis).
A child is lifted by the arm and refuses to use it, holding it slightly flexed and pronated. Which structure is likely subluxed?
What is the radial head (nursemaid's elbow)?
At the cubital fossa, the brachial artery terminates and bifurcates into these two arteries
What are the radial and ulnar arteries?
The annular ligament stabilizes this joint but can be injured when a child is swung by the arms.
What is the proximal radioulnar joint (nursemaid's elbow)?
The musculocutaneous nerve continues beyond the brachium to supply this type of innervation in the forearm.
What is cutaneous innervation to the lateral forearm?
Which muscle’s name means 'short thumb extensor'?
What is extensor pollicis brevis?
A child is lifted by the arm and refuses to use it, holding it slightly flexed and pronated. Which structure is likely subluxed?
What is the radial head (nursemaid's elbow)?
The common interosseous artery almost immediately branches into these two arteries.
What are the anterior and posterior interosseous arteries?
Name the three articulations often grouped as the 'radioulnar joints'.
What are the proximal radioulnar joint, distal radioulnar joint, and the interosseous membrane (middle joint)?
Supinator syndrome involves compression of this nerve as it passes through the supinator canal.
What is the deep branch of the radial nerve (posterior interosseous nerve)?
'Digitorum communis' is so named because…
It extends to a community of tendons that insert on digits II–V.
A patient has deep forearm pain and motor weakness in finger extensors but no sensory deficit. What condition do you suspect?
What is posterior interosseous nerve entrapment (radial tunnel syndrome)?
This superficial vein is often targeted for venipuncture due to its accessibility in the cubital fossa.
What is the median cubital vein?
This fibrocartilaginous structure cushions the distal ulna and carpals, commonly injured with falls on an outstretched hand.
What is the triangular fibrocartilage complex (TFCC)?
Distinguish between deficits caused by posterior interosseous nerve palsy versus posterior interosseous artery injury.
Nerve palsy causes motor deficits (finger/wrist extension), while artery injury causes ischemic changes but no direct motor loss.
Differentiate 'profundus' from 'superficialis' in flexor muscles.
Profundus = deep, inserting distally at DIP joints; Superficialis = superficial, inserting at PIP joints.
During wrist fracture repair, injury to the TFCC would impair what specific function?
It would destabilize the distal radioulnar joint and impair load transmission between ulna and carpals.
Explain the biomechanical reason the interosseous membrane resists proximal migration of the radius during weight-bearing.
Because its fibers run obliquely upward from ulna to radius, redirecting axial load onto the ulna and preventing proximal displacement of the radius.
Describe how the orientation of the interosseous membrane fibers permits both pronation-supination and load transfer.
The oblique fibers resist proximal migration of the radius during load, while folding during pronation/supination allows mobility without excessive stretch.
A patient presents with weakness in forearm supination and sensory loss over the thenar eminence. Which two nerves are most likely involved?
What are the radial nerve (deep branch for supination) and median nerve (sensory to thenar eminence)?
Explain why anatomists classify the hand as having '8 fingers and 2 thumbs.'
Because pollicis (thumb) muscles and structures are separated from digitorum, treated as distinct from the four fingers on each hand.
Explain how force is transmitted from the hand to the humerus during a fall on an outstretched hand (FOOSH).
Force passes through the radius → redirected via interosseous membrane to ulna → ulna to humerus at the stable humeroulnar joint.