Imaging of Upper Extremities Quiz

Imaging of Upper Extremities, CT, Radiography

• Various imaging modalities are used in upper extremity radiology, based on the clinical context and specific structures being investigated.
• X-rays and CT are often initial tools for assessing bones and joints.
• MRI provides detailed information about soft tissues, ligaments, and joint structures.
• Radiological studies are crucial in diagnosing and managing upper limb conditions.

Basic Radiographic Principles - Recap

• X-rays are produced within the X-ray tube.
• X-ray beams pass through the region of interest (ROI) onto a detector plate.
• Five main X-ray densities exist: air, fat, soft tissue, bone, and metal.

Normal Anatomy of the Shoulder

• The upper end of the humerus is visible with:
  • Greater tuberosity
  • Lesser tuberosity
  • Head
  • Surgical neck
  • Anatomical neck
• Parts of the scapula that are easily seen:
  • Glenoid cavity
  • Supraglenoid tubercle
  • Infraglenoid tubercle
  • Coracoid process
  • Acromion process
  • Lateral (or axillary) border
  • Upper ribs
• Clavicle is also visible.

Clavicle Basic Anatomy

• The clavicle is a long bone with a body and two extremities:
  • Acromial extremity which articulates with the acromion process of the scapula
  • Sternal extremity articulates with the manubrium of the sternum and the first costal cartilage.

Clavicle Measurements

• Coracoclavicular ligament (3 cm)
• Acromioclavicular ligament (1.5 cm)

Scapula

• The scapula is a flat bone forming the posterior part of the shoulder girdle. It is triangular in shape with two surfaces, three borders, and three angles.
• It sits on the superoposterior thorax, between the second and seventh ribs.
• The medial border runs parallel to the vertebral column.

Humerus

• The proximal end of the humerus consists of:
  • Head
  • Anatomic neck
  • Two tubercles: greater and lesser
  • Surgical neck
• The head is large, smooth, and rounded, lying in an oblique plane on the superomedial side of the humerus.
• The anatomic neck is below the head and narrow.
• The surgical neck is the constriction of the body just below the tubercles (site of fractures).

Elbow X-ray

• Structures visible on elbow X-rays include:
  • Humerus (lateral and medial epicondyles, coronoid process, capitulum, trochlea, supracondylar ridge)
  • Radius (radial head, radial neck, radial tuberosity)
  • Ulna (olecranon, olecranon fossa, trochlear notch)
  • Anterior fat pad, coronoid process

Elbow CT

• Structures visible on elbow CT images include:
  • Distal humerus
  • Lateral epicondyle
  • Medial epicondyle
  • Olecranon fossa
  • Olecranon process
  • Various other anatomical parts

Radius and Ulna

• The radius and ulna are long bones in the forearm.
• Proximal end is at the elbow, distal end is at the wrist joints.
• The radius and ulna bones articulate at the wrist.

Wrist X-ray

• Structures visible on wrist X-rays include:
  • Scaphoid, lunate, triquetrum, pisiform
  • Trapezium and trapezoid, capitate, hamate.
  • Metacarpals, radial and ulna styloid processes
  • Several other structures.

Wrist CT

• Structures visible on wrist CT images include (among others):
  • Extensor tendons, scaphoid, capitate, hamale, trapezoid, trapezium
  • Triquetrum, pisiform, and other anatomical structures.

Hand X-ray

• Structures visible on hand X-rays include:
  • Radius and ulna
  • Carpals (scaphoid, lunate, triquetrum, pisiform, trapezoid, trapezium, capitate, hamate)
  • Metacarpals
  • Phalanges (proximal, middle, distal)
  • Sesamoid bones

Fracture Basics - Recap

• Types of fractures include:
  • Transverse
  • Linear
  • Oblique (nondisplaced or displaced)
  • Spiral
  • Greenstick
  • Comminuted

Shoulder Dislocation

• Glenohumeral joint dislocation involves the separation of the humerus from the glenoid of the scapula.
• An X-ray will show a gap between the humeral head and glenoid fossa.

Clavicle Fracture, Elbow Dislocations, Various Fractures

• These are conditions characterized by a break in the clavicle, dislocation of the elbow joint, or a fracture in different parts of the upper limb.
• X-rays or CT scans can diagnose these conditions.

Radial Head Dislocation, Intra-articular Radial Head Fracture, Radial Neck Fracture, Distal Radius Fracture, Ulna Fracture

• These are specific types of fractures or dislocations.