A 28-year-old basketball player presents to the emergency department after falling during a game and landing on an outstretched arm. The nurse is conducting an initial assessment for a suspected shoulder dislocation. Which assessment finding would be most indicative of an anterior shoulder dislocation?
1The affected shoulder appears higher than the unaffected shoulder with the arm held in internal rotation
2The patient can easily move the arm through full range of motion despite reporting pain
3Loss of the normal rounded shoulder contour with a visible depression below the acromion process✓ 정답
4The arm is positioned in external rotation and abduction with minimal pain reported
해설
Anterior shoulder dislocation typically presents with loss of the normal rounded shoulder contour and a visible depression below the acromion due to anterior displacement of the humeral head. Other findings like pain and limited motion are common but less specific.
The correct answer is 3, loss of the normal rounded shoulder contour with a visible depression below the acromion process. This finding describes the classic "sulcus sign" or flattening of the deltoid prominence, which is the hallmark physical presentation of an anterior shoulder dislocation. In this injury, the humeral head is displaced anteriorly and inferiorly out of the glenoid fossa, leaving a visible and palpable void beneath the acromion where the humeral head should normally sit [1].
When a patient falls on an outstretched arm, the mechanism forces the humeral head anteriorly and inferiorly, stretching or tearing the anterior capsule and labrum. This anterior displacement explains why the arm is typically held in slight abduction and external rotation, not internal rotation. The visible loss of the deltoid contour is a direct result of the humeral head no longer supporting the overlying soft tissue, creating a sharp, squared-off appearance of the shoulder. This assessment finding is so characteristic that it is considered a key diagnostic clue during the initial physical examination for traumatic anterior shoulder instability (TASI) [1].
Why the Other Options Are Incorrect
Option 1: "The affected shoulder appears higher than the unaffected shoulder with the arm held in internal rotation." This description is inconsistent with an anterior dislocation. In an anterior dislocation, the humeral head moves inferiorly and medially, often making the affected shoulder appear lower or flattened, not higher. Furthermore, the arm is typically held in slight abduction and external rotation due to the position of the displaced humeral head and associated muscle spasm, not internal rotation. A shoulder appearing higher with internal rotation might suggest a posterior dislocation or an acromioclavicular joint injury.
Option 2: "The patient can easily move the arm through full range of motion despite reporting pain." This is not consistent with a shoulder dislocation. A dislocation is a mechanical block to joint movement. The displaced humeral head physically prevents normal range of motion, and any attempt at movement typically causes severe pain and muscle guarding. The patient will actively resist both active and passive motion. Full range of motion despite pain would be more suggestive of a soft tissue injury like a rotator cuff strain or contusion, not a dislocation.
Option 4: "The arm is positioned in external rotation and abduction with minimal pain reported." While the position of external rotation and slight abduction is correct for an anterior dislocation, the description of "minimal pain" is clinically inaccurate. An acute traumatic shoulder dislocation is intensely painful due to capsular stretching, ligamentous injury, and severe muscle spasm. The patient typically presents in significant distress, supporting the affected arm with the contralateral hand. The physical examination for TASI must be performed gently, as the patient will be guarding and highly sensitive to movement [1].
References (research sources)
[1]
Age- and time-specific management of traumatic anterior shoulder instability: The 2024 ESSKA-ESA formal consensus. Part 1: History taking, physical exam and imaging studies.GuidelineAlentorn-Geli E, Ângelo AC, Brilakis E, Bøe B, Ruíz-Iban M, Dyrna F, Saccomanno MF, Lacheta L, Housset V, Benea H, Fonte H, Boutsiadis A, Zampeli F, Milano G, Beaufils P, Kovacic L. (2026) · DOI: 10.1002/ksa.70336
Clinical Assessment for Anterior Shoulder Dislocation
When assessing a patient with a suspected anterior shoulder dislocation, the nurse should systematically inspect and compare both shoulders. The classic presentation includes the patient supporting the affected arm with the opposite hand, with the arm held in slight abduction and external rotation. Severe pain and muscle spasm are typically present.
Key Physical Finding
The most indicative finding is the loss of the normal rounded deltoid contour. The humeral head is displaced anteriorly and inferiorly, leaving a visible and palpable depression or void beneath the acromion process. This creates a squared-off appearance of the shoulder, often referred to as a positive sulcus sign.
Nursing Priority: Neurovascular Assessment
A thorough neurovascular assessment must be performed before and after any reduction attempt. The axillary nerve is most commonly injured. Assess sensation over the lateral deltoid (regimental badge area) and motor function by asking the patient to initiate abduction against resistance. Document distal pulses, capillary refill, and motor/sensory function of the radial, median, and ulnar nerves.
Emergency Management
Keep the patient NPO in case procedural sedation is required for reduction. Provide analgesia and apply a sling and swathe for immobilization in the position of comfort. Do not attempt to move the arm through range of motion. Prompt reduction is indicated to relieve pain and prevent neurovascular compromise.
Sulcus Sign — A visible indentation or depression just below the acromion process, indicating inferior instability or the void left by an anteriorly dislocated humeral head.
Anterior Shoulder Dislocation — The most common type of shoulder dislocation where the humeral head is forced out of the glenoid fossa anteriorly, often from a fall on an outstretched arm.
Acromion Process — A bony prominence on the scapula forming the highest point of the shoulder; a depression below it indicates loss of the normal humeral head position.
Traumatic Anterior Shoulder Instability (TASI) — A condition resulting from an initial anterior dislocation that damages the labrum and capsule, leading to recurrent instability.