An orthopaedic assessment test for shoulder 1glenohumeral instability is the Sulcus sign. The elbow is grasped and traction is applied inferiorly while the arm is straight and relaxed to the patient's side.
A depression develops directly beneath the acromion in cases of excessive inferior translation. The emergence of this sulcus is encouraging.
The sulcus sign measures the stability of the inferior glenohumeral. The examiner grabs the patient's arm and pulls inferiorly when the patient is seated or standing.
The test is considered successful if, when the humeral head is translated inferiorly, a dimple or sulcus emerges under the acromion.
The measurement of the sulcus in centimetres is the basis for numerous grading systems for the sulcus sign.
A sulcus sign of 2 cm or more, according to Tzannes and Murrell28, had a specificity of 97% for multidirectional instability, although the equivalent sensitivity was only 28%. (LOE: D).
The sulcus sign was similarly shown to be unsuccessful in excluding instability by T'Jonk and colleagues26, with a poor likelihood ratio of 0.78. (LOE: B).
The patient is seated with an arm by their side and relaxed shoulder muscles.
The examiner grasps the patient's forearm just below the elbow and pulls it outward while feeling the acromion's inferior margin for evidence of the humeral head's inferior translation.
A sulcus is regarded as a positive test result and may be a sign of inferior instability or laxity in the glenohumeral ligament.
When a sulcus sign is seen when the tester applies a downward force at the elbow with the arm in neutral rotation and resting at the patient's side, the test is deemed positive.
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Load and Shift Test for sulcus sign
The patient is sitting straight, with one arm at the side and relaxed shoulder muscles. With one hand placed over the clavicle and scapula, the examiner stabilises the shoulder. The examiner grasps the humeral head with the other hand, placing the fingers along the anterior humerus and the thumb over the posterior humeral head.
The examiner evaluates the humeral head's initial alignment with the glenoid. In order to "seat" the humerus into a central position with respect to the glenoid, it is then gently pushed anteriorly or posteriorly.
This is the test's "load portion." Then, while noting the degree of translation and end feel, the examiner pushes the humeral head anteriorly or posteriorly.
The "shift" part of the test is this. Although patient variability exists, translation of the humeral head diameter anteriorly of 25% or less is regarded as normal.
Hawkins and Mohtadi14 recommended a three-grade system for anterior translation: grade I, where the humeral head rides up to the glenoid rim translating up to 50%; grade II, where the humeral head rides over the glenoid rim translating more than 50%; and grade III, where the humeral head rides over the glenoid rim translating more than 50% but spontaneously reducing.
Apprehension and Relocation Tests
The examiner carefully twists the patient's shoulder to the side while abducting the arm to 90 degrees. An expression on the patient's face that suggests concern or panic as well as the patient's reluctance to additional movement are signs of a positive test result.
The tester next administers a posterior translation stress to the head of the humerus if the outcome of the apprehension test is positive (relocation test).
If the patient stops feeling anxious, the discomfort lessens, and further lateral rotation is allowed before the anxiety or pain returns, the test is deemed successful
These exams are largely intended to look for shoulder instability issues brought on by trauma or anatomical instability.
Inferior and multidirectional instability
With the patient seated and their arms at their sides, the sulcus sign is elicited. The examiner distracts the distal humerus downward while keeping an eye on the lateral acromial edge with the arm in neutral rotation.
A sulcus that is inferior to the lateral acromion and measures in centimetres can form due to inferior instability. The anterior capsule and rotator interval are put under tension as the test is then executed with maximum external rotation. Sulcus sign persistence during external rotation is a sign of rotator interval dysfunction.
Patients with multidirectional instability may exhibit any of the physical examination findings previously covered, and many show symptoms of ligamentous laxity in several joints, including the shoulder on the opposite side.
An objective method of evaluating generalised articular mobility is the Beighton score. It has a scoring range of 0 to 9, with a score of 3 or higher in an adult with skeletal maturity being linked to generalised hypermobility.
One point is given if the patient can perform each of the following movements: extending the left or right small finger 2metacarpophalangeal beyond 90 degrees, touching the left or right thumb to the volar forearm, extending the left or right elbow beyond 10 degrees, extending the left or right knee beyond 10 degrees, and placing the palms of the hands flat on the ground with the knees fully extended.
A diagnosis of generalised ligamentous laxity requires a score of 4 or higher, but a score of 2 or higher has also been linked to a history of glenohumeral instability.
Sulcus Sign (Superior Capsule).
The sulcus sign is used to evaluate the superior capsular restraints in an adducted neutral position, including the superior glenohumeral ligament and coracohumeral ligament.
In order to lessen the impact of the biceps and triceps, the examiner applies an inferiorly directed stress through the upper arm.
The typical bilateral displacement in a patient with multidirectional instability is noticeably large. Although there are no specific references regarding the independent validity of this test, it seems to be useful when used as a component of a battery of tests and as part of a general assessment.
The sulcus sign: what does it mean?
The sulcus sign measures the stability of the inferior glenohumeral. The examiner grabs the patient's arm and pulls inferiorly when the patient is seated or standing.
The test is considered successful if, when the humeral head is translated inferiorly, a dimple or sulcus emerges under the acromion.
Conclusion:
The superior glenohumeral ligament and coracohumeral ligament laxity cause inferior instability of the glenohumeral joint, which is evaluated with the Sulcus Test. This will mostly be used to describe the sulcus test.
Additional resources and citations
- 1glenohumeral instability
- 2metacarpophalangeal