It is difficult to identify and challenging to diagnose a shoulder labral tear, or a SLAP (Superior Labrum Anterior and Posterior) tear. These injuries frequently occur along with other shoulder issues, and symptoms can be similar.
Arthroscopy is considered the best method to diagnose a SLAP tear. Arthroscopy allows the most clear and detailed imaging, which a physical examination may not be accurate, and an magnetic resonance imaging (MRI) scan could miss a small tear.
A three-part clinical approach could diagnose this injury. It may also help decide the course of treatment.1 The clinical approach includes the patient’s medical history, a physical examination and imaging tests, as follows:
There are several topics a physician and patient may discuss during the medical history evaluation, including the patient’s symptoms and any previous treatment.2
Examples of discussion topics include:
- Particular sports or activities associated with pain. Pain could be related to overhead or throwing sports, such as baseball. Athletes may notice a decline in sports performance and reduced shoulder power. Pain or discomfort can also be associated with some activities, including lifting objects overhead.
- Initial cause of pain. SLAP tears are often a result of repetitive movements, where the labrum degenerates over time; therefore, it may be challenging to pinpoint when the pain began. But sometimes this injury is due to acute trauma, including falling on an outstretched arm.
- Location of pain. Patients generally describe a deep, aching pain that is difficult to pinpoint. Locking, popping, clicking or grinding sensations in the shoulder may also be noted.
During this examination, the physician inspects the patient’s shoulder strength, stability and range of motion. The head and neck may also be examined to ensure the pain is not due to a “pinched nerve.”2 There are several specific tests a physician can conduct to detect a tear, but opinions differ on the reliability of these tests to accurately diagnose this injury.
There are several challenges with the physical examination: a physical test may not be precise; and there are several types of labral tears that a test may or may not identify.3 Given these ambiguities, imaging testing may be recommended.
An MRI scan is often done to diagnose a SLAP tear and other potential injuries to the muscles, tendons, ligaments, and cartilage in the shoulder. Because of the many overlapping and interwoven structures in the shoulder, it is possible for an MRI scan to miss a smaller tear. It is also possible for an MR arthrogram, or imaging to produce false positives, as one study found.4 While it is not a perfect diagnostic test, an MRI scan is the best imaging (noninvasive) means of diagnosing a SLAP tear.
Sometimes a physician requests x-rays. A labral tear will not appear on an x-ray because the labrum consists of soft tissue, but x-rays can identify or rule out any bone-related shoulder problems.