Shoulder and Elbow cases SLAP tears1

A 24-year-old, left-hand-dominant, businesswoman presents to clinic with 2 days of right shoulder pain. Two days prior she was playing soccer when she tripped and fell on an outstretched right hand with a slightly flexed and abducted shoulder. She felt immediate pain in her right shoulder and is now having pain and grinding and popping with overhead activity. She is otherwise healthy and takes no medications. On examination, she has grinding and popping with shoulder motion and a positive O’Brien’s test, Hawkin’s sign, Speed’s test, and pain with anterior apprehension testing. The rest of the examination is normal. X-rays are normal.

If conservative management with 6 weeks of physical therapy (PT) and NSAIDs fails, what is the next step in management?

1. CT arthrography

2. Diagnostic MRI

3. Diagnostic arthroscopy

4. Shoulder x-rays

5. Diagnostic MR arthrogram

 

Discussion

The correct answer is (E). MRI (Answer B) is the best type of imaging modality for imaging soft tissues, such as the labrum. In a labrum tear, there will be high signal intensity in the area of the tear usually around the biceps anchor, and sometimes a glenoid labral cyst can be found which has been found to be highly sensitive and specific for a labrum tear. MRI has been shown to have an 84% to 98% sensitivity, 63% to 91% specificity, and 74% to 96% accuracy. An MR arthrogram (Answer E) involves adding intra-articular contrast to an MRI, which increases visual contrast between the intra-articular soft tissue structures and synovial fluid, improving the sensitivity and specificity of MRI for diagnosing SLAP tears. Because of this increased benefit and with a high suspicion for a labral tear, an MR arthrogram should be obtained.

CT arthrography (Answer A) is better than MRI for imaging bone, but it is

inferior to MRI for imaging soft tissue such as the labrum and rotator cuff.

Diagnostic arthroscopy (Answer C) is the gold standard for diagnosing a SLAP tear. It is the only way to definitively diagnose a SLAP tear. However, an MR arthrogram is less invasive than surgery and can help differentiate between various shoulder pathologies (such as rotator cuff vs. labrum tears) in order to reach a diagnosis and deliver the correct treatment. If, however, there is strong suspicion for a SLAP tear and MR arthrogram is negative, a diagnostic arthroscopy is a reasonable next step.

Shoulder x-rays (Answer D) were already obtained in this patient, so they do not need to be repeated. In addition, x-rays will not reveal SLAP tears. In a case where no x-rays were obtained, though, an AP, scapular AP, supraspinatus outlet, and axillary x-ray of the affected shoulder should be obtained in order to identify other pathologies that could be the source of shoulder pain.

An MR arthrogram shows the superior labrum is detached from the superior glenoid, and the biceps tendon anchor is disrupted. How would this tear be classified according to the Snyder classification?

1. Type I

2. Type II

3. Type III

4. Type IV

5. Type V

 

Discussion

The correct answer is (B). The Snyder classification of SLAP tears is the first widely used classification systems for SLAP tears and consists of types I to IV (see Fig. 2–22A–B and Table 2–3). In type I tears (Answer A), there is fraying of the glenoid edge of the superior labrum, but the biceps tendon and superior labrum are both firmly attached to the biceps anchor and glenoid edge. In type II tears (Answer B), the biceps tendon and the superior labrum are detached from the superior glenoid edge and biceps anchor. In type III tears (Answer C), there is a bucket-handle tear of the superior labrum, but the remainder of the superior labrum and biceps tendon remain firmly attached to the glenoid rim and biceps anchor. In type IV tears (Answer D), there is a bucket-handle tear of the superior labrum that extends into the biceps tendon with extension of parts of the labral flap or biceps tendon into the joint space, and the remainder of the labrum and biceps tendon remain firmly attached to the glenoid rim and biceps anchor. Type V tears (Answer

E) do not exist. Complex lesions do exist and typically consist of a combination of type II and IV tears.

 

 

 

Figure 2–22 (A–B) Snyder classification of rotator cuff tears in cartoon and arthroscopic views. (From Mileski RA, Snyder SJ. Superior labral lesions in the shoulder: pathoanatomy and surgical management. J Am Acad Orthop Surg. 1998;6(2):121–131.)

 

Table 2–3 SNYDER CLASSIFICATION DESCRIPTION AND TREATMENT

 

Snyder Classification	Description of Labrum	Description of Biceps Tendon	Treatment
Type I	Fraying of glenoid edge	Intact	Labrum debridement
Type II	Detached from glenoid	Detached from anchor	Labrum repair if unstable and <25–30 y/o Biceps tenodesis if unstable and >30–35 y/o Labrum debridement if degenerative at any

Type III	Bucket-handle tear	Intact	age Labrum debridement with MGHL repair if detached
Type IV	Bucket-handle tear	Tear extends into biceps	If young or old and <30% biceps torn, labrum and biceps debridement If young and >30% biceps torn, labrum repair and biceps tenodesis/tenotomy If old and >30% biceps torn, labrum debridement and biceps tenodesis/tenotomy

From Mileski RA, Snyder SJ. Superior labral lesions in the shoulder: pathoanatomy and surgical management. J Am Acad Orthop Surg. (1998);6(2):121–131.

 

If a type II tear is confirmed during diagnostic arthroscopy in the above patient, what treatment should be administered?

1. Labrum debridement

2. Biceps tenodesis

3. Labrum repair

4. Labrum reconstruction

5. Biceps tenotomy

 

Discussion

The correct answer is (C). Correct treatment of SLAP tears follows correct tear classification. If a patient has an unstable type II tear and are <25 to 30 years old, they should have a labrum repair, and that is the case in this patient. If a patient has an unstable type II tear and are >30 to 35 years old, they should have a biceps tenodesis. If they have a degenerative type II tear that is associated with other lesions, a labrum debridement (Answer A) can be performed and repair is usually unnecessary, especially if the patient is old and less active. This patient has an acute, unstable Type II labrum tear and is young, so she should have a labrum repair.

If a patient has a type I or III tear, they should have a labrum debridement (Answer A). With a type III tear, this involves resecting the unstable labrum fragment and repairing the middle glenohumeral ligament (MGHL) to the labrum if it became detached with the unstable fragment.

If a patient is young or old and has a type IV tear, and if the tear involves less than 30% of the biceps tendon (meaning that greater than 70% of the biceps tendon is still intact), the unstable parts of the labrum and biceps tendon should be debrided. If a patient is old and has a type IV tear that involves more than 30% of the biceps tendon, a labrum debridement and biceps tenodesis/tenotomy should be performed (Answers B and E). If a patient is young and has a type IV tear that involves more

than 30% of the biceps tendon, a repair of the labrum and biceps tenodesis/tenotomy should be performed. Labral reconstructions (Answer D) are rarely performed (see Table 2–3).

If, during diagnostic arthroscopy, the only significant finding is a cord-like, middle glenohumeral ligament that attaches to the base of the biceps anchor, and there is no labral tissue attached to the anterosuperior glenoid rim, what should be done?

1. Labrum repair by attaching the middle glenohumeral ligament to the glenoid rim

2. Nothing

3. Labrum reconstruction

4. Biceps tenodesis

5. Biceps tenotomy

 

Discussion

The correct answer is (B). This arthroscopic finding described is a Buford complex (Fig. 2–23B), and it is a normal anatomic variant that occurs in about 1.5% of shoulders. It consists of a cord-like middle glenohumeral ligament (MGHL) that attaches to the biceps anchor with a lack of labral tissue at the anterosuperior glenoid rim. If a Buford complex is misdiagnosed as a SLAP tear and the MGHL were anchored to the glenoid rim (Answer A), the patient could have significantly restricted range of motion, especially in external rotation.

 

 

 

Figure 2–23 Two normal variants of labral anatomy. A, Top: sublabral foramen at 2 o’clock position. B, Bottom: Buford complex. (From Mileski RA, Snyder SJ. Superior labral lesions in the shoulder: pathoanatomy and surgical management. J Am Acad Orthop Surg. 1998;6(2):121–131.)

There is no need to reconstruct the labrum (Answer C) or to tenodese or tenotomize the biceps tendon (Answers D and E) in this case because there is no pathology of these structures.

Other normal variants found in the shoulder that should be known include a sublabral foramen (Fig. 2–23A) at about 2 o’clock position on a right shoulder that occurs in about 3.3% of shoulders and a sublabral foramen with a cord-like MGHL that occurs in about 8.6% of shoulders. Another normal variant is a meniscoid superior labrum in which the inner lip of the labrum partially covers the glenoid articular cartilage. True SLAP tears can be differentiated from these normal variants because they show hemorrhage or granulation tissue at the base of the biceps tendon or under the labrum, and there is a space between the glenoid articular cartilage and the superior labrum/biceps tendon that can be mobilized 3 to 4 mm with traction of the biceps tendon.

 

Objectives: Did you learn...?

 

 

Diagnose a SLAP tear through imaging? Classify SLAP tears?

 

Recognize normal labrum variants that can resemble SLAP tears?