Arthroscopic Shoulder Stabilization with Suture Anchors:

Anterior and Posterior Instability

Jeffrey S. Abrams, M.D.

Princeton Orthopaedic & Rehabilitation Associates, P.A.

Princeton, New Jersey

I. Instability Principles:
Excessive glenohumeral translation that creates symptoms and dysfunction. Tissue can be stretched (elastic, deformation), elongated (plastic deformation), torn or detached.

Labral detachments can be reattached to the glenoid with suture anchors. Capsular tears can be repaired to the labrum with sutures or to the glenoid with anchors. Capsular redundancy can “shrink” due to thermal injury, create pleat with sutures, or cut and advance with capsule shift.

Instability Classification:

Onset: Traumatic, Atraumatic, Overuse

Degree: Dislocation, Subluxation, Apprehensive

Direction: Anterior, Posterior, Inferior (multidirectional)

Occurrence: Acute (initial), Recurrent, Chronic

Suture Anchor Choices:

Radiographic visible (metallic) vs. invisible (absorbable, plastic).

Permanent vs. Absorbable.

Screw-in anchors vs. Push in anchors

Surgeons should ask:

Sliding knots need anchors with large eyelets.

Screw-in anchors require placement prior to tissue pass.

Concepts:

Tissue failure: multiple sites.

1-healing potential: Periosteal elevation, synovial fluid.

Predisposition: Activity or anatomy

Static combined with Dynamic Stabilizers

II. Anterior Instability

Pathologic Lesions:

Labral detachment

Capsule stretch tear

Hill-Sachs lesion

Glenoid edge

Superior labral biceps

Indications:

Repair if recurrent with disability, acute or initial dislocation in high risk population, patients’ desire to reduce risk of recurrence.

Be Aware:

Stiff shoulders

Axillary nerve injury

Surgical Goals:

Labral reattachment

Capsule tension restored to limit translation of humeral head

Maximize range of motion

Early rehabilitation for proprioceptive reintegration and strengthening

Technique for Anterior Repair:

Develop viewing portal posteriorly. The anterior portals are developed with an outside-in technique to maximize the skin distance between portals to avoid instrument crowding. Internally these portals converge between the biceps long head and the superolateral border of the subscapularis.

Elevate and mobilize the labrum and inferior portion of the capsule. Prepare the glenoid edge and neck. Protect the soft tissue structures and abrade the cortical bone. Confirm with visualization from posteriorly and anterosuperior portals

Drill holes are made on the articular surface along the detached labrum. A drill guide is helpful to precisely place and space holes. Angle the drill deep (not parallel) to the articular surface.

Place a suture anchors in the inferior hole and test pull-out. Sutures can be permanently braided (#2) or monofilament absorbable (#1). Depending on the type of anchor and suture, the order of the anchor placement and suture passage can be reversed.

Use a suture retriever Blitz/(Linvatec) Suture Retriever (Innovasive device) or a suture hook Spectrum (Linvatec) with a suture shuttle (Linvatec) to pass suture through the capsule. It is helpful to use two cannulas to pass shuttle or retrieve sutures. Be gentle with sutures and leave slack during passes. It is important to advance the inferior capsule ligament superiorly during this step. As the suture is tensioned, the labrum reduces to the articular edge, and the capsule is advanced.

Tying the knot: you may choose to place the next anchor prior to making a knot, if the holes are close together. Sliding knots can make re-approximation easier, and should be placed on lateral post along the ligament. Otherwise, a series of half-hitches are advanced, alternating directions and every two throws alternate post. At least five throws are used. Steps are repeated with implants superiorly placed.

Augmentation can be done at:

- Capsule labral junction

- SGHL and MGHL rotator interval

- Capsular shrinkage

Table test: Place scope anterosuperiorly and visualize external rotation up to 30*. Capsule and labrum should tension appropriately without separation from the glenoid.

III. Anterior Capsulorrhaphy / Plication

Pathology:

Labrum may be intact with permanent plastic deformation of the capsule ligaments.

Suture Anchors Optional:

May use intact labrum for capsule plication or tuck.

Capsular shrinkage:

Conceptually, heating collagen to 65 degree changes cross linkage of collagen and creates shrinkage (scar). Visual changes noted and healing process may accentuate shrinkage.

Surgical Goals:

Reduce pouch

Advance capsule superiorly with tension

Augment labrum with capsule thickening

Rotator cuff interval capsule closure

Caution:

Anatomic variants

Joint symmetry - do not over-tighten one side, possibly creating increase translation in the opposite direction.

IV. Posterior Instability

The posterior portion of the inferior glenohurneral ligament plays an important role in stability when the arm is abducted. The posterior capsule has significant redundancy with a valley between the labrum and the posterior portal entrance. The posterior capsule above the inferior glenohumeral ligament is thin. Anterosuperior capsule and labrum (Rotator Cuff Interval) plays a role in posteroinferior laxity when the arm is adducted.

Stability requires capsular balance, structural support and dynamic positioning of the glenoid.

Concept:

Traumatic labral detachment - direct blow.

Poster-inferior instability/laxity - overuse.

Posterior Technique:

Examination under anesthesia: Look at translation including sulcus signs, load and shift. Compare to contralateral extremity.

Develop posterior viewing portal (may decide to use two posterior portals -inferior portal is 2 cm below). Inspect the joint.

Develop anterior superior portal. Change to view from here. Examine anteroinferior and posterior anatomy.

If labrum is detached. use outside-in to create portal for suture anchor. This needs to be more laterally placed to increase angle of entrance into the posterior glenoid edge. More commonly, the labrum is intact and the unstable head rides over the labrum.

Use a curved suture hook and take a pass through the inferior capsule. Draw the capsule superiorly and pass a second time through the labrum. This creates thickening to the leading edge of the posterior portion of the IGHL. A #1 PDS suture can be passed and tied.

If permanent sutures are more desirable, this repair can be reinforced. Make a anteroinferior portal above the subscapularis tendon. Using a curved suture retriever through the posterior portal. The “seam” of the repair can be reinforced beginning inferiorly and working superiorly. Introduce the suture from the anterior inferior portal, across the joint, and into the retriever. Tie knots as sutures are placed.

Return to posterior portal for visualization. Inspect the superior and middle anterior glenohumeral ligaments with the cannula laterally placed. A suture hook can be passed beneath the biceps and through the superior band of the middle glenohumeral ligament adjacent to the glenoid. Begin closure medially and work towards the cannula. The last suture can be drawn out to the bursal side, replacement of the scope in the bursae can allow the last knot to be tied.

Capsular shrinkage to IGHL and rotator cuff interval may be another alternative. Axillary nerve injury has been reported in the anterior-inferior quadrant. Careful movement and working closer to the glenoid reduces this risk. Capsular shrinkage may be used to augment suture techniques.

V. Post Operatively:

Ultrasling

Isometrics/scapular stabilization

Active external rotation

Functional return delayed