SLAP lesion describes labral tears specifically located in the anterosuperior quadrant of the glenoid, near the origin of the long head of the biceps tendon. There are several proposed mechanisms, although it is still unclear what exactly causes SLAP lesions. These mechanisms can be divided into acute traumatic events or chronic repetitive injuries that lead to failure. An example of an acute traumatic event would be falling onto an outstretched arm, which may result in a SLAP lesion, secondary to impaction of the humeral head against the superiorlabrum and the biceps anchor. Repetitive overhead activity has been hypothesized as a common mechanism for producing SLAP lesions.
Originally 4 types of SLAP lesions have been described (Snyder et al 1990). This has been
expanded to include:
Type V: a Bankart lesion that extends superiorly to include a Type II SLAP lesion
Type VI: an unstable flap tear of the labrum in conjunction with a biceps tendon separation
Type VII: a superior labrum and biceps tendon separation that extends anteriorly, inferior to the middle glenohumeral ligamentAnatomy of GHJ
Incidence & Prevalence of SLAP Lesions
The incidence of SLAP lesions has been reported in the literature to range between 6-26% of all shoulder injuries evaluated arthroscopically (Powell et al 2008).
Assessment: Signs and Symptoms
If SLAP lesions remain untreated there can be a potentially devastating injury that can lead to chronic pain, as well as a significant loss of function and performance. It is not uncommon to encounter associated pathology when treating a SLAP lesion. Patients who have SLAP tears can also have rotator cuff tears and other labral pathology.
A comprehensive approach involving a thorough history and physical examination, adequate imaging, and ultimately diagnostic arthroscopy is often necessary to recognise and appropriately treat SLAP lesions. Numerous tests have been described to be specifically designed to determine the presence of labral pathology, including the active-compression test, the compression-rotation or grind test, Speed’s test, the clunk test, the crank test, the anteriorslide test, the biceps load test, the biceps load test II, and the pain provocation test. Although many of these tests have been shown to accurately diagnose SLAP lesions, their reproducibility among multiple examiners is uncertain. Thus it is important to correlate the patient’s symptoms with the physical examination findings to make the diagnosis. MRI is the gold standard imaging modality for diagnosing SLAP lesions (Dodson and Altchek (2009).
Conservative management of SLAP lesions is often unsuccessful, particularly when there is a component of glenohumeral joint instability or when a concomitant rotator cuff tear is present. There may be, however, a small subset of patients, particularly those with type I SLAP lesions, who are amenable to conservative treatment. Indications for surgery are patients who fail conservative management, patients who have a SLAP lesion with significant rotator cuff tears ( 50%), and patients with large associated labral tears who exhibit severe mechanical symptoms (Dodson and Altchek (2009).