The Elbow
True or False? in the superior radioulnar joint the annular ring forms 1/5 of the joint
False. 4/5 for the annular ring and 1/5 for the radial notch
True or false? The elbow joint is a pivot joint
False. It is a hinge joint
true or false? The posterior aspect of the medial collateral ligament is the primary stabilizer to valgus stress.
False. The anterior part from ROM 20-120
describe the axis of motion of the forearm
It is longitudinal going from the radial head to the ulnar head
Describe the axis of motion in the elbow
It is oblique. It goes through the Capitulum and Trochlea. From lateral to medial and superior to inferior.
Describe the arthrokinematics of the inferior radioulnar joint
It's concave moving on convex. so everything in the same direction
Describe the arthrokinematics of the superior radioulnar joint.
It's convex moving on concave. bone motion and roll in the same direction, glide in the opposite direction
What is the AROM for elbow flexion?
0-145 degrees
What is the PROM for elbow flexion?
0-160 degrees
How many degrees of freedom at the elbow joint?
1
What are the 3 functions of the Radial collateral ligament?
1) Stabilize the humeroradial joint 2) provide some varus stability 3) oppose longitudinal distraction of the humeroradial joint
Give 3 anatomical reason as to how Flexion is increased for the elbow
1) The humeral condyles are tilted anteriorly at a 45 degree angle 2) The Coronoid fossa allows more room for the coronoid process of the ulna 3) The Radial fossa allows more room for the radial head
What are the 3 components of the proximal radioulnar joint?
1) concave radial notch 2) convex radial head 3) annular ligament
What are the 2 main functions of the elbow joint?
1) to move the hand in space 2) to provide stability while the hand is performing certain tasks
At what angle does the brachialis produces its greatest torque?
100 degrees
How many articulations are found at the elbow joint? name them
2 humeroulnar and humeroradial
The elbow joint capsule contains how many joints? Name them
3. Humeroulnar, Humeroradial and Superior Radioulnar
The Bicep Brachii produces more torque at what angles?
80 to 100 degrees
What is the ROM for supination and pronation?
90 degrees
True or false? The intra-articular disk in the inferior radioulnar joint is convex superiorly and inferiorly.
false. concave on both sides.
True or false? The joint capsule is stronger anteriorly
fasle. (laterally and medially)
Which movements does the elbow joint allow?
flexion and extension
What is the secondary role of the anconeus?
To provide stability during pronation and supination
True or False? The extensor carpi radialis brevis helps in elbow flexion
True
True or false? The intermediate radioulnar joint is a syndesmosis
True
True or false? The pronator teres is a prime mover during elbow flexion.
True
True or false? the superior and inferior radioulnar joints are diarthrodial joints
True
true or false? the elbow joint is a compound joint
True
Which muscle is considered the workhorse of the elbow flexors?
The brachialis
The angle formed by the humerus and forearm in extension is called?..
The carrying angle (about 5 degrees in males and 10-15 in females)
What accessory movements occur during elbow extension?
ABduction and Pronation
What accessory movements occur during elbow flexion?
ADduction and Supination
What are the accessory movements at the elbow?
Adduction-Abduction-Supination and Pronation
The elbow joint moves around which axis and in what plane?
Around the coronal axis and in a sagittal plane
Name the prime movers in elbow flexion
Brachialis, Biceps Brachii, Brachioradialis and Pronator Teres
describe the arthrokinematics during elbow flexion and extension
Concave on Convex...everything in the same direction
True or false? During slow pronation the pronator teres is active
False
True or false? The brachialis is a shunt muscle
False
The Superior radioulnar joint moves in what plane and around which axis?
In the transverse plane and around a vertical axis.
What role does the annular ligament plays?
It binds the radius to the radial notch on the ulna
What type of joint is the inferior radioulnar joint?
Pivot or trochoid.
Describe passive insufficiency for the biceps
Shoulder extended, elbow extended, forearm pronated
what articulates between the humerus and the radius?
The Capitulum and the radial head
Which ligament opposes VARUS stress?
The lateral collateral or radial collateral ligament
Which head of the triceps is the strongest during extension?
The lateral head
Which ligament limits pronation at the distal radioulnar joint?
The posterior radioulnar ligament
Name the two muscles responsible for pronation
The pronator quadratus and the pronator teres
Name the two muscles responsible for supination
The supinator and the Biceps brachii
True or false. During pronation and supination the Radius is the moving bone
True.
True or False? The Bicep Brachii is a spurt muscle
True. spurt or mobility
When does the triceps produce its greatest torque?
at 90 degrees of elbow flexion
At what angle is the biceps the primary supinator?
at 90 degrees
describe a position of passive insufficiency for the triceps
shoulder flexion and elbow flexion
Which other muscle assits during elbow extension?
the anconeus
Which muscle is always active during elbow flexion?
the brachialis
Which ligament is most often injured during elbow dislocation?
the medial collateral ligament
Which ligament opposes VALGUS stress
the medial collateral or ulnar collateral ligament
Which head of the triceps is the work horse during extension?
the medial head
Which ligaments limit supination?
the oblique cord and the anterior radioulnar ligament
Which ligament reinforces the inferior aspect of the superior radioulnar joint?
the quadrate ligament
what articulates between the humerus and ulna?
the trochlea of the humerus and the trochlea notch of the ulna
When does the pronator teres participates in elbow flexion?
when a load/resistance is applied
