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    Arthroscopic Suprascapular Nerve Decompression and Posterior Labral Repair

    A 55-year-old patient with chronic mild shoulder pain presents when she suddenly develops weakness and an inability to perform normal activities. Will an arthroscopic procedure alleviate her symptoms?

    Authors

    Mark Ghobrial, DO, and Luke S. Austin, MD

    Disclosures

    Dr. Ghobrial has no disclosures relevant to this article. Dr. Austin has disclosed that he receives research funding from Zimmer.

    Case Presentation

    A 55-year-old female patient presents with a 1-day history of right shoulder pain and weakness that started when she reached behind her car seat to grab her purse. She has had intermittent, mild right shoulder pain for the last 2 years, but she had not sought any medical treatment for it until now.

    The patient complains of posterolateral shoulder pain, weakness with external rotation, and an inability to perform activities such as reaching behind her head. She denies radiation of pain, numbness, or tingling.

    She has no significant medical or surgical history.

    Physical Examination

    • No swelling, ecchymosis, focal tenderness, or obvious deformity of the right shoulder.
    • Full active range of shoulder motion: 5/5 strength of abduction, 4/5 strength with flexion and internal rotation, and 2/5 strength with external rotation
    • Positive lag sign with external rotation at neutral and 90° abduction
    • Sensation intact to light touch distally
    • Palpable radial pulse

    Differential Diagnosis

    • Rotator cuff tear
    • Cervical radiculopathy
    • Suprascapular nerve palsy

    Imaging: Radiographs

    • Anteroposterior, scapular-Y, and axillary lateral views of the right shoulder obtained (Figures 1a-c)
    • Mild degenerative changes at the acromioclavicular joint and slight density over the humeral head at the insertion of the rotator cuff

    Figures 1a-c. Preoperative radiographs.

    Imaging: MRI

    • MRI of the right shoulder obtained (Figures 2a-f)
    • Posterior labral tear with associated paralabral cyst in the spinoglenoid notch
    • Denervation changes in the infraspinatus muscle indicating compression of the suprascapular nerve

    Figures 2a-f. Preoperative MRI.

    Diagnosis

    • Posterior labral tear and spinoglenoid notch cyst causing pain and weakness with external rotation secondary to compression of the suprascapular nerve

    Treatment

    As recommended by the authors, the patient agreed to undergo a right shoulder arthroscopic suprascapular nerve decompression by evacuating a spinoglenoid notch cyst and repairing the one-way valve in the posterosuperior labrum.

    Advantages

    • Allows for direct decompression of cyst
    • Repair of labral tear closes the 1- way valve and prevents future cyst formation and nerve compression.
    • Low morbidity

    Disadvantages

    • Risk of incomplete decompression of spinoglenoid cyst
    • Risk of recurrent posterior labral tear and cyst formation
    • Risk of neurovascular injury with aspiration

    Procedure

    • The patient was placed in the lateral decubitus position with 8 pounds of arm traction.
    • Using a posterior and anterior portal, a diagnostic arthroscopy was performed which demonstrated a posterior labral tear with intact biceps anchor (Figure 3).
    • An arthroscopic tissue liberator was used to elevate the labrum and potentially decompress the cyst. However, the cyst was unable to be fully accessed and decompressed with this method (Figure 4).
    • A third anterosuperior viewing portal was created and the anterior and posterior portal were cannulated. The posterior labrum and glenoid rim were rasped and prepared for repair. The indication to repair the labrum is to close the one-way valve and stop the flow of joint fluid into the spinoglenoid notch cyst (Figure 5).
    • Two Bioraptor Suture Anchors (Smith & Nephew; Andover, Massachusetts) were placed in the posterior glenoid. A suture lasso (Arthrex; Naples, Florida) placed through the posterior portal was used to pass suture around the labrum. It is imperative not to grab the capsule and instead simply compress the labrum to the glenoid.
    • The sutures were then tied through the posterior portal in the standard fashion.
    • Once the labral tear was repaired, an 18-gauge needle was inserted under arthroscopic-assisted visual guidance, into the posterior capsule at the site of the repair to decompress the cyst (Figure 6).
    • Gelatinous fluid (1 mL) was aspirated from the cyst (Figures 7a-b).

    Figure 3. Posterior labral tear.

    Figure 4. The cyst cannot be reached with an arthroscopic tissue liberator.

    Figure 5. Posterior labrum repaired.

    Figure 6. An 18-gauge needle is used to decompress the cyst.

    Figure 7a-b. Fluid aspirated from the cyst.

    Postoperative course­­

    The patient tolerated the procedure well, without any complications. She was placed in a sling and discharged home from the PACU with instructions to remain non-weight-bearing.

    2-week postoperative visit

    • Well-healed incision with no erythema
    • Neurovascularly intact
    • Remains in a sling and non-weight-bearing

    1-month postoperative visit

    • 45° external rotation, 150° active forward flexion
    • 4/5 strength with abduction, 3/5 strength with external rotation
    • VAS pain score of 50 mm
    • Sling removed and patient started on passive range-of-motion exercises
    • 1-pound weight-bearing allowed

    2-month postoperative visit

    • 50° external rotation, 170° active forward flexion
    • 4/5 strength with abduction and external rotation, 5/5 strength with internal rotation
    • ASES score of 68.3
    • VAS pain score of 30 mm
    • SANE score of 85%
    • Light strengthening with 10-pound weight restriction

    Author Information

    Mark Ghobrial, DO, and Luke S. Austin, MD, are from The Rothman Institute, Philadelphia, Pennsylvania.

    Shoulder Section Editor, Rothman Institute Grand Rounds

    Luke S. Austin, MD