Elbow And Forearm Complex

Front 1

List the components of the “elbow and forearm complex” - specify joints.

Back 1

Humeroulnar joint
Humeroradial joint
Proximal radioulnar joint
Distal radioulnar joint

Front 2

List the osteokinematic motions, degrees of freedom and plane in which motion
takes place at Elbow joint proper?

Back 2

Flexion and Extension. 1 degree of freedom. Sagittal plane, medial-lateral axis of rotation.

Front 3

Identify location and describe orientation as well as direction of the joint axis of
motion for the elbow proper.

Back 3

Axis-Medial-lateral
Location of the axis-capitulum and trochlea
Orientation-inferior-medial to superior-lateral. Going uphill from medial to lateral.

Front 4

Define “cubitus valgus” more commonly known as_______ and
define cubitus varus.

Back 4

Larger or abnormal carrying angle.
Smaller carrying angle. Normal is 15 degrees.

Front 5

Describe the shape of the trochlea. (see p134)

Back 5

Spool of thread, push pin, hour glass on its side, one bell is going to be larger. Medial side of trochlea extends more distal

Front 6

What is the significance of the shape of the trochlea on “cubitus valgus”?

Back 6

the more distal the medial bell of the trachlea goes, more cubital valgus . Ulna is pushed lateral. No carrying angle-wlak with elbow out, maybe because of fracture to distal humerus. When elbow is extended, elbow goes inward. Gun Stock deformity.

Front 7

Identify the specific arthrokinematic motion for each joint.

Back 7

Humeraounlar
Ulna moving on humerus
Concave trochlear notch of the ulna around the convex trochlea of the humerus. Same directions. Flexion-anterior/superior
Extension-posterior/inferior.

Humeroradial
Radius moving on humerus
Fovea of the radius rolling and sliding across the convexity of the capitulum.
Same directions

Front 8

Apply the Convex-Concave Rule to each joint motion.

Back 8

Concave on convex except in closed chain, when the humerus is moving on ulna or radius.

Front 9

What percent of compression force passes through the radiocarpal joint and by
what mechanism does the interosseous membrane transmit some of this force to
the ulna?

Back 9

80%, Inferior-medial to superior-lateral interosseous membrane transfers the force to ulna. Most common fracture is styloid process of radius. Further up the radius, the more force is transfered to the ulna.

Front 10

What assists in keeping the forearm stable during pulling activities of the
forearm/upper extremity?

Back 10

Brachioradialis
Obilque cord

Front 11

List the osteokinematic motions, degrees of freedom and plane in which motion
takes place at forearm joints?

Back 11

Pronation and supination. 1 degree of freedom. One plane of motion. Transverse. 2 degrees for complex