O’Brien’s Test for SLAP Tears: How to Perform & Interpret

Published October 26, 2026 Read time 7 min read Readers 44

What Is O’Brien’s Test?

O’Brien’s Test, also known as the Active Compression Test, is an orthopedic physical examination maneuver used to evaluate shoulder pain and identify possible injuries involving the glenoid labrum, particularly SLAP lesions (Superior Labrum Anterior to Posterior tears).

The test is also used to assess potential abnormalities of the acromioclavicular (AC) joint, including AC joint pathology that may cause pain over the top of the shoulder.

Originally described by O’Brien and colleagues in 1998, the Active Compression Test is commonly performed during a clinical shoulder examination by orthopedic surgeons, sports medicine physicians, and physical therapists.

The examination involves applying resistance to the patient’s arm in two different rotational positions and comparing the location and intensity of the resulting shoulder pain.

What Is O’Brien’s Test Used For?

The primary purpose of O’Brien’s Test is to help identify shoulder conditions involving the labrum or acromioclavicular joint.

These include:

SLAP lesions: Injuries involving the superior portion of the glenoid labrum, extending from anterior to posterior.
Glenoid labral tears: Damage to the cartilage rim surrounding the shoulder socket.
Acromioclavicular joint pathology: Conditions affecting the AC joint, including degenerative changes and joint injuries.

The glenoid labrum is a fibrocartilaginous structure that contributes to shoulder stability by deepening the glenoid socket. Its superior portion also provides an attachment site for the long head of the biceps tendon.

SLAP tears may occur after a fall onto an outstretched hand, repetitive overhead activity, or traumatic loading of the shoulder. These injuries are particularly relevant in throwing athletes and individuals who participate in repetitive overhead sports.

How to Perform O’Brien’s Test

O’Brien’s Test is performed in two stages to compare shoulder symptoms during internal and external rotation.

Step 1: Shoulder Internal Rotation (Thumb Down)

Position the patient in a standing or seated position, with the affected arm relaxed initially.
Ask the patient to forward flex the affected shoulder to 90 degrees, keeping the elbow fully extended.
Move the arm approximately 10–15 degrees across the body into horizontal adduction.
Internally rotate the shoulder until the thumb points downward and the palm faces posteriorly.
Apply a downward force to the distal forearm or wrist while the patient attempts to maintain the arm’s position.
Ask the patient to describe the presence, intensity, and exact location of any pain or painful clicking.

Step 2: Shoulder External Rotation (Palm Up)

Repeat the examination while maintaining the shoulder at 90 degrees of forward flexion and approximately 10–15 degrees of horizontal adduction.

This time, externally rotate the shoulder so that the palm faces upward.

The examiner again applies a downward force while the patient resists the movement.

Compare the symptoms experienced during both positions, paying particular attention to whether the pain decreases or disappears with external rotation.

Clinical tip: The location of pain is an important part of interpreting O’Brien’s Test. Deep shoulder pain and pain localized to the AC joint may indicate different underlying conditions.

What Is a Positive O’Brien’s Test?

An O’Brien’s Test is considered positive when pain occurs during the thumb-down position and decreases or disappears when the test is repeated with the palm facing upward.

The location of the pain helps guide clinical interpretation.

Positive O’Brien’s Test for a SLAP Tear

A positive result suggesting a possible SLAP lesion is characterized by:

Deep pain within the glenohumeral joint during resisted shoulder internal rotation.
A reduction or disappearance of pain during resisted external rotation.
Sometimes, painful clicking or catching inside the shoulder.

These findings may indicate superior labral pathology, although they cannot independently confirm a SLAP tear.

Positive O’Brien’s Test for AC Joint Pathology

Pain localized over the top of the shoulder, specifically at the acromioclavicular joint, may suggest AC joint pathology rather than a labral tear.

Pain that decreases during the palm-up position can support this interpretation.

However, further clinical assessment is necessary because several shoulder disorders may produce overlapping symptoms.

O’Brien’s Test Sensitivity and Specificity

The diagnostic accuracy of O’Brien’s Test has been investigated extensively, with considerable variation between published studies.

In the original 1998 study, O’Brien and colleagues reported exceptionally high diagnostic accuracy for detecting labral injuries, with approximately:

Sensitivity: 100%
Specificity: 98–99%

However, subsequent investigations have not consistently reproduced these results.

A systematic review published in Shoulder & Elbow in 2019 analyzed 18 studies involving 3,091 patients and reported the following pooled diagnostic values for identifying SLAP lesions:

Diagnostic Measure	Pooled Result
Sensitivity	71.5%
Specificity	51.9%

Sensitivity represents the ability of a test to identify patients who have the condition, while specificity indicates its ability to correctly identify patients without the condition.

These pooled findings indicate that O’Brien’s Test has limited diagnostic accuracy when used alone.

A subsequent systematic review and meta-analysis published in the American Journal of Sports Medicine in 2023 also evaluated combinations of shoulder examination maneuvers. It found that combining O’Brien’s Test with the Crank Test provided relatively high sensitivity among the two-test combinations studied.

Clinical interpretation: A positive O’Brien’s Test may increase clinical suspicion of a SLAP lesion, but it is not sufficient to establish the diagnosis. Similarly, a negative test does not reliably exclude a labral injury.

Limitations of O’Brien’s Test

Although O’Brien’s Test is widely used during shoulder examinations, several limitations should be considered.

First, the maneuver is not specific to SLAP lesions. Patients with rotator cuff disorders, subacromial pain, or AC joint abnormalities may also experience pain during resisted shoulder movement.

Second, the interpretation depends heavily on the patient’s ability to accurately describe the location and character of their symptoms.

Third, the presence of painful clicking does not necessarily confirm a labral tear, as mechanical symptoms can arise from different shoulder structures.

For these reasons, O’Brien’s Test should be interpreted alongside the patient’s medical history, injury mechanism, shoulder range of motion, strength assessment, and other appropriate clinical tests.

When necessary, magnetic resonance imaging (MRI), MR arthrography, or further specialist evaluation may help clarify the diagnosis.

Clinical Significance of O’Brien’s Test

O’Brien’s Active Compression Test remains a useful component of a comprehensive orthopedic shoulder examination.

Its greatest clinical value lies in helping clinicians assess symptom location and identify possible labral or acromioclavicular pathology.

However, current evidence does not support using this maneuver as a standalone diagnostic test for SLAP lesions.

A comprehensive examination, supported by appropriate investigations when indicated, provides a more reliable basis for clinical decision-making.

Frequently Asked Questions (FAQ)

1. What is O’Brien’s Test used to diagnose?

O’Brien’s Test is primarily used to evaluate suspected SLAP lesions and other glenoid labral injuries. It may also help identify acromioclavicular joint pathology based on the location of the patient’s pain.

2. How do you perform O’Brien’s Test?

The patient raises the affected arm to 90 degrees of forward flexion, adducts it 10–15 degrees across the body, and internally rotates the shoulder until the thumb points downward. The examiner applies downward resistance, then repeats the maneuver with the palm facing upward to compare symptoms.

3. What indicates a positive O’Brien’s Test?

A positive test occurs when shoulder pain is reproduced during the thumb-down position and decreases or disappears with the palm facing upward. Deep shoulder pain suggests possible labral pathology, while pain over the AC joint may indicate acromioclavicular pathology.

4. Is O’Brien’s Test accurate for diagnosing SLAP tears?

O’Brien’s Test has limited diagnostic accuracy when performed alone. A systematic review involving 3,091 patients reported a pooled sensitivity of 71.5% and specificity of 51.9%, indicating that additional clinical assessment is necessary.

5. What does a negative O’Brien’s Test mean?

A negative O’Brien’s Test means the maneuver does not reproduce the characteristic change in shoulder pain. However, a negative result does not completely exclude a SLAP tear or another shoulder injury.

6. Can O’Brien’s Test distinguish a SLAP tear from an AC joint injury?

The test may help distinguish these conditions based on pain location. Deep pain within the shoulder suggests possible labral pathology, whereas localized pain at the top of the shoulder is more suggestive of AC joint involvement. Nevertheless, it cannot reliably differentiate these conditions without additional evaluation.

7. What other shoulder tests can be performed with O’Brien’s Test?

Other clinical maneuvers that may be considered include the Crank Test, Biceps Load II Test, Anterior Slide Test, and Speed’s Test. The choice of examination depends on the patient’s symptoms and suspected underlying injury.