Exam 2 - Elbow, Wrist and Hand Flashcards
What are the three bones in the elbow and forearm?
Humerus, Radius, Ulna
What are the four articulations in the elbow and forearm?
Humeroradial Joint, Humeroulnar Joint, Proximal radioulnar joint, distal radioulnar joint
What is the elbow joint technically considered and why?
Trochogingylmoid Joint since it is a hinge and pivot joint
What two parts of the distal humerus articulate with the radius?
Capitellum and Radial Fossa
What parts of the distal humerus articulates with the ulna?
Trochlea, Coronoid Fossa, Olecranon Fossa
What part of the radius articulates with the humerus?
Radial head and fovea
What is different about the articulation of the radius with the humerus?
Both parts are concave
What parts of the radius articulates with the ulna?
Radial head, ulnar notch and styloid process
What parts of the ulna articulates with the humerus?
Trochlear Notch, Olecranon Process, Coronoid Process
What parts of the ulna articulate with the radius?
Radial Notch, Ulnar Head, Styloid Process
In the humeroradial joint, which surface is concave?
Radial head
In the humeroradial joint, which surface is convex?
Capitellum of humerus
Which surface moves in the humeroradial joint?
Concave radial head
Which direction does the radial head roll and slide during open chain flexion at the humeroradial joint?
Anteriorly
Which direction does the radial head roll and slide during open chain extension at the humeroradial joint?
Posteriorly
Which direction does the radial head spin during open chain supination at the humeroradial joint?
Posteriorly
What direction does the radial head spin during open chain pronation of the humeroradial joint?
Anteriorly
Which surface is concave in the humeroulnar joint?
Trochlear notch
Which surface is convex in the humeroulnar joint?
Trochlea
Which surface moves in the humeroulnar joint?
Concave trochlear notch
Which direction does the trochlear notch roll and slide during open chain flexion or the humeroulnar joint?
Anteriorly
Which direction does the trochlear notch roll and slide during open chain extension of the humeroulnar joint?
Posteriorly
Which surface is concave in the proximal radioulnar joint?
Radial notch
Which surface is convex in the proximal radioulnar joint?
Medial portion of the radial head
Which surface moves in the proximal radioulnar joint?
Convex medial portion of the radial head
Which direction does the medial portion of the radial head roll during open chain supination?
Posteriorly
Which direction does the medial portion of the radial head roll during open chain pronation?
Anteriorly
Which surface is concave in the distal radioulnar joint?
Ulnar notch of radius
Which surface is convex in the distal radioulnar joint?
Ulnar head
Which surface moves in the distal radioulnar joint?
Concave ulnar notch
Which direction does the concave ulnar notch roll and slide during open chain supination at the distal radioulnar joint?
Posteriorly
Which direction does the ulnar notch of the radius roll and slide during open chain pronation at the distal radioulnar joint?
Anteriorly
What muscles flex the elbow?
Biceps Brachii, Brachialis, Brachioradialis, Pronator Teres
What nerve innervates the Biceps Brachii muscle?
Musculocutaneous Nerve
What elbow flexor crosses two joints?
Biceps Brachii
What nerve innervates the brachialis?
Musculocutaneous Nerve
What nerve innervates the brachioradialis?
Radial nerve
What muscle innervates the pronator teres?
Median nerve
What muscles extend the elbow?
Triceps Brachii, Anconeus
What nerve innervates the elbow extensors?
Radial nerve
What are the primary muscles that pronate the forearm?
Pronator Teres, Pronator quadratus
What nerve innervates the primary muscles that pronate the forearm?
Median nerve
What are the secondary muscles that pronate the forearm?
Flexor carpi radialis, palmaris longus, brachioradialis
What nerve innervates the flexor carpi radialis?
Median nerve
What nerve innervates the palmaris longus?
Median nerve
When does the brachioradlis assist in pronation?
If the forearm is already supinated
What nerve innervates the brachioradialis?
Radial nerve
What are the primary muscles that supinate the forearm?
Supinator, Biceps Brachii
What nerve innervates the supinator?
Radial nerve
What are the secondary muscles that supinate the forearm?
Radial wrist extensors, extensor pollicis longus, extensor indicis, brachioradialis
What nerve innervates the secondary muscles that supinate the forearm?
Radial nerve
When does the brachioradialis assist in supination of the forearm?
If the forearm is already pronated
What are the primary static stabilizers of the humeroulnar joint?
Humeroulnar joint, anterior bundle of the medial collateral ligament, lateral collateral ligament
What are the secondary static stabilizers of the humeroulnar joint?
Humeroradial joint, common flexor and extensor tendons, joint capsule
What are the dynamic stabilizers of the humeroulnar joint?
All muscles that cross the elbow joint
What structures limit motion when the elbow is resting in extension?
Anterior bundle of the medial collateral ligament, olecranon process, and secondary elbow muscles
What structures limit motion when the elbow is resting in flexion?
Posterior bundle of the medial collateral ligament, posterior joint capsule, and soft tissue
Where is the interosseus membrane?
Between the radius and ulna
What is the function of the interosseus membrane?
Disperse forces between the radius and ulna
What are the three parts of the interosseus membrane?
Central band, oblique band, distal oblique fibers
What happens when force is applied to the radial collateral ligament?
Interosseus membrane is pulled taut, most of the force is through the humeroulnar joint
What is the carrying angle?
Lateral deviation of the ulna relative to the humerus that exists because movement at the humeroulnar joint is not purely horizontal
What is the typical degree of the carrying angle in males?
5-10 degrees
What is the typical degree of the carrying angle in females?
10-15 degrees
What is another name for carrying angle?
Cubitus Valgus
What is it called when your carrying angle is greater than normal?
Excessive cubitus valgus
What is it called when your carrying angle is less than normal?
Cubitus Varus
What are the two joints of the wrist?
Radiocarpal, Midcarpal
What bones are included in the radiocarpal joint?
Scaphoid, Lunate, Radius
What bones are included in the midcarpal joint?
Capitate, Lunate, Scaphoid
What are two other ways to describe the anterior part of the wrist?
Palmar, volar
What is another way to describe the posterior aspect of the wrist?
Dorsal
What bones make up the proximal row of the carpals?
Scaphoid, Lunate, Triquetrum, Pisiform
What bones make up the distal row of carpal bones?
Trapezium, Trapezoid, Capitate, Hamate
What is a FOOSH?
Fall on an outstretched hand
Why do we have more ulnar deviation than radial deviation?
More space in the ulnocarpal space, and the proximal row is looser than the distal row
What is the TFCC?
Triangular Fibrocartilage Complex
What is the purpose of the TFCC?
Binds the distal radius to the ulna while allowing the radius and attached hand to rotate around the ulna
What is the axis of rotation in the wrist?
Center of the capitate
What is the axis and plane for flexion/extension of the wrist?
M/L axis, Sagittal plane
In general, what are the arthrokinematics of the wrist?
Distal segment on proximal segment
What is the axis and plane for ulnar/radial deviation of the wrist?
A/P Axis, Frontal plate
Which part of the wrist is convex?
Distal
Which part of the wrist is concave?
Proximal
Which direction does the wrist roll and slide during movements?
Opposite directions
At which joint is the more radial and ulnar deviation; midcarpal or radiocarpal?
More at the midcarpal
What other motion is combined with radial deviation?
Slight extension
What other motion is combined with ulnar deviation?
Slight flexion
Which way do the carpals roll in radial and ulnar deviation?
Roll to radial side
Which way do the carpals slide during radial and ulnar deviation?
Slide to the ulnar slide
Which side of the forearm are the wrist extensors?
Posterior side of the forearm
Do the wrist extensors act at the hand or only the wrist?
Only the wrist
In how many planes do the wrist extensors produce torque?
Two planes
What is needed to produce pure single plane movement of the wrist extensors?
A neutralizer
What muscles are on the anterior side of the forearm?
Flexors and pronators
Do wrist flexors and pronators work at only the wrist or do some work on the fingers?
Some work on fingers too
How many planes do the flexors produce torque in?
2
How do the wrist flexors produce movement in two planes?
FCU flees and ulnar deviates wrist unless it is stabilized by FCR
What is needed to produce pure single plane movement in the wrist flexors?
Neutralizer
What are the two things the hands are good for?
Manipulation and Exploration
What are the 3 arches of the hand?
Longitudinal, Proximal Transverse, Distal Transverse