Upper Limb II Flashcards
(26 cards)
Which bones articulate with the Carpal Bone?
Only the Radius articulates with the Carpal Bone,
Not the Ulna.
What is a consequence of only the Radius articulating with the Carpal Bones?
Forces e.g. Fall on outstretched hand are transmitted through the Radius only,
Making it more likely to Fracture from these forces compared to the Ulna.
What are the main bony features of the Radius?
- Head of Radius
- Neck of Radius
- Radial Tuberosity
- Oblique Line
- Interosseous Border
- Dorsal Tubercle
- Styloid Process of Radius
What are the 2 Articular surfaces on the Radius?
Articular Surface to Scaphoid Bone (lateral)
Articular Surface to Lunate Bone (medial)
What is the purpose of the Interosseous Border?
Attachment for Interosseous Membrane
Membrane between Radius and Ulna
What does the Head of the Radius Articulate with?
Capitulum of Humerus
“CAP ON HEAD”
What is the main structural difference between the
Radius and the Ulna? Why?
Radius: Distal End is Larger than its Head.
Ulna: Distal End is Smaller than its Head.
So the two bones articulate (fit) together well.
What is the Proximal Radial - Ulnar Joint?
Located near the Elbow,
An Articulation between the Head of the Radius,
And the Radial Notch of the Ulna.
What is the importance of the
Proximal Radial - Ulnar Joint?
This joint is classified as a Pivot Joint,
Responsible for Pronation and Supination of the Forearm.
What is the Anular Ligament?
AKA: Orbicular Ligament
Is a Strong Band of Fibres that encircles the head of the Radius,
And retains it in contact with the Radial Notch of the Ulna.
Prevents Radial Head Dislocation
What are the main features of the Ulna?
- Olecranon Process
- Coronoid Process
- Trochlear Notch
- Radial Notch
- Ulnar Tuberosity
- Interosseous Border
- Styloid Process of Ulna
Which segments of the Ulna help to form the
Elbow Joint?
Olecranon Process
Coronoid Process
Trochlear Notch
What movement does the Trochlear Notch limit?
Extension of the Elbow.
Which Nerve is risk of injury with an
Olecranon Fracture?
Ulnar Nerve
However it can grow back.
What is the Distal Radial - Ulnar Joint?
Located near the Wrist,
An Articulation between the Head of the Ulna,
And the Ulnar Notch of the Radius.
Where are the Styloid Processes found?
At the Distal End of both Radius and Ulna
What attaches to the Ulnar Styloid Process?
Ulnar Ligament
What type of joint is formed by the
Interosseous Membranes?
Syndesmosis
A Fibrous Joint between Two Bones
Which other long bones have a Syndesmosis?
Tibia and Fibula
What is the most common Fracture of the Forearm?
Colles Fracture:
Fracture of the Distal End of the Radius.
A complete Transverse Fracture within the Distal 2cm of the Radius.
The Distal Fragment is displaced Dorsally and is often Comminuted (broken into pieces).
How does Colles Fracture happen?
The Fracture results from Forced Dorsiflexion of the Hand,
Usually as the result of trying to ease a fall by outstretching the Upper Limb.
Which Nerve can be damaged by a Radial Fracture
and what does this lead to?
Radial Nerve:
Leads to a Wrist Drop
How is the Deformity from Colles Fracture described?
The deformity is referred to as a dinner fork deformity,
Because a “jog” occurs just Proximal to the Wrist,
Which is produced by the Posterior Displacement and Tilt of the Distal Fragment of the Radius.
Who is more susceptible to Fractures?
The most Common Fracture in Adults over 50.
Occurs more frequently in women,
Because there bones are often weakened by Osteoporosis.
