Fracture Pattern Terminology Quiz

Objectives

• To learn the anatomical structures on radiographs of the forearm, wrist, and hand.
• To identify radial head subluxation, radial head fractures, Monteggia fracture-dislocations, and Galeazzi fracture dislocations based on etiology, pathophysiology, history, physical, and radiographic images.

Posterior Shoulder Dislocation - Bankart lesion

• In a posterior shoulder dislocation, the humeral head is locked in internal rotation, which is confirmed on the Y view via a light bulb sign.
• Anterior and medial humeral head defects manifest as a trough line sign, indicating a reverse Hill-Sachs lesion.
• A small inferior glenoid fracture fragment indicates a reverse Bankart lesion.
• Posterior labrocapsular periosteal sleeve avulsion (POLPSA) lesion displays an intact periosteum with detached posterior labrum from the glenoid.
• With POLPSA, an axial T1-weighted fat-suppressed MR arthrographic image demonstrates high-signal contrast interposed between the glenoid and the torn, mildly displaced labrum with attached periosteum.

Nursemaid's Elbow (AKA Radial Head Subluxation)

• Occurs usually in children, as a result of pulling the arm, leading to the radial head slipping out of the annular ligament.
• Those affected will present with pain in elbow, holding hand with palm in pronation & unwilling to move at elbow.
• It is a clinical diagnosis that does not always appear on X-ray; other injuries may be ruled out.
• Ultrasound or MRI may be needed in diagnosis.
• Reduction can be conducted by placing a thumb on the radial head and supinating when flexed, or extending then hyperpronating (less uncomfortable).

Elbow - Radial Head Fracture

• H&P reveals tenderness over the radial head with local swelling and pain with rotation and flexion of the forearm.
• Diagnosis is made with plain radiographs, an AP and true lateral view of the elbow.
• The posterior fat pad is not ordinarily visualized on a lateral radiograph as it is tucked away within the olecranon fossa.
• On a true lateral radiograph, the anterior fat pad is seen as a small triangular radiolucent shadow anterior to the distal humeral diaphysis.
• Hemarthrosis results in an upward displacement of the anterior fat pad and a backward displacement the posterior fat.
• X-rays can reveal radial head fracture, with associated posterior and anterior sail signs
• Ossification Centers: CRITOE: Capitellum (1 yr), Radial Head (3 yrs), Internal Epicondyle (5 yrs), Trochlea (7 yrs), Olecranon (9 yrs), External Epicondyle (11 yrs).

Forearm - Monteggia Fracture Dislocation

• Occurs most often in children after receiving a blow on the forearm when trying to protect themselves.
• It can be associated with posterior interosseous n. (PIN) injury (thumb and wrist extensors).
• An AP & lat view X-ray can reveal Fx of the ulna with associated dislocation of the radial head at the elbow, generally anterior.

Forearm - Galeazzi Fracture Dislocation

• Results from a FOOSH injury with deformity.
• Diagnose with AP and lateral X-rays of the forearm, wrist, and elbow.
• Characterized by Fx of the distal radius with dislocation/subluxation of the distal radio-ulnar joint (DRUJ) at the wrist.
• The radius is fractured, and the wrist is dislocated.

General Radiology Overview

• Radiography, or conventional radiograph, involves “plain films” or "standard film" and uses broad beam ionizing radiation to create images, is related the subjects' density
• Fluoroscopy involves a continuous X-ray image and can be used to guide injections.
• Computed axial tomography (“CT”) involves sectional anatomy imaging and gives a better view of bones.
• Magnetic resonance imaging (“MRI”) is useful in identifying small changes within soft tissue.
• Ultrasound "US" Nuclear Imaging Interventional radiology
• PACS involves a picture archiving and communication system which replaces conventional radiological film.

Radiography Indications

• X-rays have several indications: Bone injuries, Infections, Foreign objects, Tumors, Other conditions like arthritis and osteoporosis and tooth decay.
• X-rays have the capacity to evaluate and plan treatments, and to destroy cancerous tumors and cells by damaging their DNA,

Radiography Dangers and Contraindications

• Dangers include ionization radiation which produces free radicals and cell mutations that can lead to cancer or anomalies (Leukemia, Breast Cancer, Thyroid Cancer, Brain Cancer)
• Contraindications include pregnancy, prenatal exposure during weeks 8-15 of gestation, mental retardation and reduced head circumfrence

Radiation Safety

• ALARA means "As Low As Reasonably Achievable" and is a central tenet of safety.
• Three principles of radiation safety: time, distance, shielding Other safe methods: U/S or MRI; Avoid repeat testing
• Look for a facility and physician who is board-certified

Cardinal Planes

• Coronal plane divides the body into anterior and posterior (belly and back) sections.
• Transverse plane divides the body into superior and inferior parts, roughly perpendicular to the spine.
• Sagittal plane is any imaginary plane parallel to the median plane.

CT Scans Key Points

• Can undergo Bone Reconstruction in 3D for implants, enabling tailored bone replacements, and for detecting the scan range for a CT scan.
• CT scans are topograms, AKA scanograms or localizer radiographs, and are 2D X-ray images.
• CT scans can also be "windowed" to optimizes the visibility of different types of pathology.
• In cases of a bone injury, suspected intracranial hemorrhage, abdominal injury or pain. spine alignment, fracture detection and evaluation and tumor staging a CT scan should be ordered.

Test your knowledge of fracture pattern descriptions, including displacement types like medial, shortening, and angular displacement. Learn to identify key anatomical landmarks for assessing fracture alignment on radiographs.