Colles' fracture is a fracture of the?

Appeared in: JODHPUR AIIMS SNO-2018

Explanation

A Colles' fracture is defined as a fracture of the distal metaphysis of the radius, typically within 2-3 cm of the wrist joint.
The mechanism of injury is a fall onto an outstretched hand (FOOSH), which forces the wrist into dorsiflexion.
This results in the distal fracture fragment being displaced dorsally (posteriorly) and often radially, leading to the classic 'dinner fork' deformity visible on a lateral view.

Option A: While a fracture of the ulnar styloid process often accompanies a Colles' fracture (in about 50-60% of cases), the primary fracture defining the condition is in the radius.
Option B: A fracture of the proximal end of the radius involves the radial head or neck, which is located at the elbow joint, not the wrist.
Option D: The humerus is the bone of the upper arm. A fracture of its shaft is a completely different injury, usually caused by direct trauma to the arm.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Anatomy of forearm fractures, specifically Colles' fracture as background academic context rather than a clinical decision trigger.
A priority nursing intervention for a suspected Colles' fracture is to perform a thorough neurovascular assessment of the affected hand (checking pulse, capillary refill, color, temperature, sensation, and motor function) to rule out median nerve damage or compartment syndrome.
Patient education is crucial, especially for older adults with osteoporosis. Nurses should provide information on fall prevention strategies and dietary intake of calcium and Vitamin D to reduce the risk of future fractures.
What if the distal fragment was displaced ventrally (palmar)? This would be a Smith's fracture (or reverse Colles' fracture), which is typically caused by a fall onto the back of the hand, forcing the wrist into flexion.

How to Approach the Question

First, identify the key term in the question: 'Colles' fracture'.
Recall the specific anatomical definition of this eponymously named fracture.
Analyze the options provided, which are all different locations on the bones of the upper limb.
Systematically eliminate the options that do not match the definition. A fracture of the humerus (upper arm) or the proximal radius (elbow) can be quickly ruled out.
Differentiate between the distal radius and ulna. A Colles' fracture specifically refers to the radius.
Select the option that correctly identifies the distal end of the radius as the location of the fracture.

Concept Tested & Keywords

QoKUNSN26LEA6lB1kDiA1t

E6 Physiology Ganong 27e Vol 2 Part 3 p. 23-25

E6 Anatomy Applied Ashalatha 4e p. 262-264

E6 Anatomy BDChaurasia V1 10e p. 32-34

Practise the full JODHPUR AIIMS SNO-2018

Attempt every question from this paper in a timed mock, then review the full solution for each one.