A 30-year-old man presents after a fall. He complains of severe shoulder pain and inability to move his arm. On examination, the arm is slightly abducted and externally rotated. The X-ray is given. What is the most likely diagnosis?

1. A

   Anterior dislocation

2. B

   Posterior dislocation

3. C

   Fracture clavicle

4. D

   Proximal humerus fracture

Appeared in: INI-CET EXAM -2025

Explanation

• Anterior dislocation is the correct diagnosis as it perfectly matches the classic clinical presentation and radiological evidence.
• The patient's arm is held in a position of slight abduction and external rotation, which is a hallmark sign of this injury.
• The X-ray confirms the displacement of the humeral head anteriorly and inferiorly out of the glenoid socket.
• This injury is the most common type of shoulder dislocation, often resulting from a fall on an outstretched hand, as described in the scenario.

Why Other Options Were Wrong

• Option B: A posterior dislocation is incorrect because it presents with the arm held in adduction and internal rotation, the opposite of this patient's presentation.
• Option C: A fracture of the clavicle would cause pain, swelling, and deformity directly over the collarbone. It does not typically cause the specific abducted and externally rotated arm posture seen in a shoulder dislocation.
• Option D: While a proximal humerus fracture can occur from a fall, the primary finding on this X-ray is the complete displacement of the humeral head from the glenoid socket (a dislocation), not a fracture line through the bone itself.

Related Visual

• Visual 1: Diagram - A comparison diagram showing the typical arm posture for anterior (abducted, externally rotated) versus posterior (adducted, internally rotated) shoulder dislocations.
• Visual 2: Annotated X-ray - An anteroposterior (AP) X-ray of an anterior shoulder dislocation with labels pointing to the displaced humeral head, the empty glenoid fossa, and the coracoid process, under which the head often comes to rest.
• Visual 3: Anatomical Illustration - An illustration showing the path of the axillary nerve around the surgical neck of the humerus, explaining its vulnerability during an anterior dislocation.

Clinical Relevance

• Nursing practice connection: Use the key finding related to The key concept is the diagnosis of shoulder joint injuries by correlating clinical presentation with radiological findings to guide bedside assessment, documentation, and the next nursing action.
• A critical nursing responsibility is to perform and document a thorough neurovascular assessment of the affected limb both before and after reduction. This includes checking for sensation over the deltoid area (axillary nerve), radial pulse, and motor function of the hand.
• Anterior dislocations have a high rate of recurrence, especially in young, active individuals. Patient education should include information on strengthening exercises for the rotator cuff muscles to improve shoulder stability post-reduction.
• Associated injuries are common, such as a Bankart lesion (a tear of the anterior glenoid labrum) and a Hill-Sachs lesion (a compression fracture on the posterolateral humeral head). These injuries increase the risk of future instability.

How to Approach the Question

• First, analyze the clinical information provided in the stem: a 30-year-old man, a fall, and severe shoulder pain.
• Identify the key physical examination finding: the arm is held in a position of abduction and external rotation. This is a classic, textbook sign.
• Next, examine the provided X-ray. Compare the position of the humeral head to the glenoid fossa (the socket). Notice that the humeral head is not in the socket but is displaced.
• Determine the direction of displacement. On this AP view, the head is medial and inferior to the glenoid, which indicates an anterior dislocation.
• Correlate the classic clinical sign (abducted, externally rotated arm) with the definitive X-ray finding (anterior displacement) to confidently select 'Anterior dislocation'.
• Briefly consider the other options. Posterior dislocation has the opposite arm position. A fracture would show a break in the bone, which is not the primary finding here.

Concept Tested & Keywords

• Concept Tested: The key concept is the diagnosis of shoulder joint injuries by correlating clinical presentation with radiological findings.
• Stem keywords: shoulder pain, fall, abducted, externally rotated, X-ray
• Lead-in keywords: most likely diagnosis
• Clinical cues: The patient's arm position (abducted and externally rotated) is a pathognomonic sign for anterior shoulder dislocation.

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