Forearm and hand bones/joints Flashcards
Articulating surface: Concave surface of radial head and capitulum of humerus
Radiohumeral joint
Articulating surface: trochlear notch of ulna and trochlea of humerus
Ulnohumeral joint
Radial/Ulnar humeral joint classification
uniaxial hinge, synovial joint
Radial/Ulnar humeral Movements permitted/ plane
Flexion/Extension
Med/Lat axis, Sagittal plane
Radial/Ulnar humeral Capsule
Weak anteriorly/posteriorly
Strengthened med/lat by “collateral ligaments”
medial / Ulnar collateral
triangular shaped, anterior, posterior, oblique bands
limits “vagus” motion (inward)
lat / Radial collateral
fan shaped
limits “varus” motion (outward)
articulating surface: edge of radial head, 1/5 articulates w ulna at any time
Proximal radioulnar joint
Proximal radioulnar joint classification
uniaxial, pivot
synovial joint
Proximal radioulnar joint movements permitted
axis/plane
Supination/pronation
Mechanical axis of radius (no plane)
Proximal radioulnar joint Capsule
Continuous w capsule of radio/ulno humeral joints
Annular ligament
encircles the radial head and ensures correct radial alignment with respect to the humerus and
ulna
Oblique cord
attaches ulna and radius anteriorly
limits / restricts- supination and inferior radial displacement
Olecranon Bursae
Subtendinous: Between olecranon of ulna and triceps tendon
Subcutaneous: between post aspect of olecranon and superficial fascia
Fat pads
outside synovial membrane, but inside capsule
offers cushion/protection
Articulating surface: Interosseous borders of radius/ulna
middle/intermediate radioulnar joint
middle/intermediate radioulnar joint classification
fibrous syndesmosis, amphiaroidal joint
interosseous membrane
Attaches between interosseous borders of radius and ulna
fibre direction of the interosseous membrane help w FOOSH
Articulating surface: Head of ulna, ulnar notch of radius
Distal radioulnar joint
Distal radioulnar joint classification
uniaxial pivot, synovial joint
Distal radioulnar joint: movements permitted/plane
Supination & pronation
Distal radioulnar joint Capsule
encloses the joint but is deficient superiorly
palmar/volar & dorsal radioulnar ligaments
transverse orientation between distal radius & distal surface of ulna
trifolar/ triradiate cartilage/ disc
-Attaches between Ulnar notch of Radius and Ulnar styloid
- seperates the distal Radioulnar joint from the wrist bone (radiocarpal joint)
- cushions impact between carpals, radius, and ulna
Articulating surface: Distal radius & trifolar cartilage (concave)
Proximal row of carpals - scaphoid, lunate
Radiocarpal joint (wrist)
Radiocarpal joint classification
biaxial condyloid, synovial joint
Radiocarpal joint: movements permitted/ plane
Flexion/Extension
med/lat axis, sagittal plane
radio ulnar deviation: ant/post axis, frontal plane
Radiocarpal joint Capsule
attaches distal radius and ulna, and proximal carpals with numerous folds
Palmar radiocarpal ligament
long & short radiolunate, radioscaphoid & radiotriquetral bands
limit / restrict- wrist extension, cause the hand to follow radius in supination
posterior radialcarpal ligament
attaches distal radius and radial styloid to triquetrum and lunate
limit / restrict- wrist flexion, cause the hand to follow radius in pronation
ulnocarpal ligament (anterior and posterior)
attaches ulna and trifolar cartilage to lunate and capitate and triquetrum
limits wrist extenion/flexion
Medial/ulnar collateral
- attaches between ulnar styloid and triquetrum
- limits / restricts- radial deviation, strengthens capsule
lateral/radial collateral
- attaches between radial styloid, scaphoid, trapezium and 1st metacarpal
- limits / restricts- ulnar deviation, strengthens capsule
Articulating surface: proximal row of carpals: Scph, lun, triq (concave)
Distal row: trpzm, trpzd, cap, ham (Convex)
Intercarpal / midcarpal joint
Intercarpal / midcarpal joint classification
nonaxial plane, synovial joint
Intercarpal / midcarpal joint movements permitted/ plane
gliding
motion at the midcarpal joint occurs primarily with wrist flexion - extension and ulnar - radial
deviation
interosseous ligaments
attach between carpals (same row)
limits joint distraction
