Arthroscopic Bankart Repair: Accessory Posterior Portal With Slotted Cannula for Lowest Capsulolabral Access

Abstract

We present a novel technique for safe establishment of the accessory posterior portal using a slotted cannula. Arthroscopic Bankart repair is a common procedure. A variety of arthroscopic techniques have been described in the literature, commonly using the posterior portal for visualization and the anterior portal with a working cannula. The accessory posterior portal enables elegant access to the lower part of the capsulolabral junction, a firmer grasp and mobilization of the tissue, quick and easy tool exchange using a slotted cannula, and clearer suture placement because of the flat, direct working angle. The skin incision is made small without the need for an arthroscopic cannula, and the portal location is in a relatively safe zone. The use of the accessory posterior portal along with a slotted cannula shortens the duration of the operative procedure and improves safety and performance.

Shoulder instability is common, with an incidence of 11.2 cases per 100,000 persons per year for traumatic anterior glenohumeral dislocation.¹ The most common cause of anterior shoulder instability is a traumatic injury causing an anterior dislocation, often associated with detachment of the anteroinferior glenoid labrum and inferior glenohumeral ligament (IGHL) from the glenoid Bankart lesion.² Treatment of recurrent instability includes surgical stabilization.³ Treatment traditionally has included open Bankart repair to restore the normal anatomy of the anterior soft-tissue structures. Arthroscopic techniques for Bankart repair have evolved considerably over the past 2 decades with reasonable success rates.^3,4 Repair of the anteroinferior capsulolabral disruption associated with anterior shoulder dislocations is the standard treatment for this pathology.^5-8 Arthroscopic treatment offers the advantage of a minimally invasive approach with less soft-tissue scarring, restriction in motion, and subscapularis failure.^4,9-11

A detrimental intraoperative complication is inadequate anchor positioning.¹² This most commonly occurs because anchors are placed too superiorly on the glenoid. Inadequate tensioning of the glenohumeral ligaments or capsule can lead to postoperative laxity and, eventually, recurrence of the dislocation.^12-16

Adequate arthroscopic access to the inferior aspect of the glenohumeral joint is therefore crucial for proper anchor placement and manipulation of the inferior glenohumeral complex. Access to the inferior recess is sometimes challenging using the anterior portal because of the convexity of the humeral head, which blocks the direct instrumental line.^15,17

The accessory posteroinferior (API) portal provides safe, simple linear access to the inferior glenohumeral capsular recess. The use of this portal facilitates manipulation of the IGHL and suture passage at the most inferior part of the capsule.^17-19 Table 1 shows the advantages and challenges of using the API portal for arthroscopic Bankart repair.

Table 1.

Advantages and Challenges of Arthroscopic Bankart Repair With Access to Lowermost Capsulolabral Junction Using API Portal With Slotted Cannula

Advantages	Challenges
The portal is anatomically safe.	An additional incision is required.
A small incision is used.	The technique is easier to perform with an assistant.
Use of the portal enables convenient “parking” for suture manipulation.	The portal is in proximity to the axillary nerve and thus must be established under vision with a spinal needle.
There is easy access to the superior labrum (useful for SLAP repair).
There is easy access to the lower part of the capsulolabral junction.
Use of the portal allows a firmer grasp and mobilization of capsular tissue.
Quick and easy tool exchange is possible using the slotted cannula.
A direct working angle is used.
The anteroinferior portals are also a solution for lower access, but maneuvering the tissue close to the orifice of the cannula is difficult.
The slotted cannula through the API portal enables easier manipulation and placement of sutures in remplissage procedures.
Arthroscopic HAGL can be managed through the API portal using the slotted cannula for tool exchange.

Surgical Technique

With the patient under general anesthesia, the shoulder is examined for range of motion, laxity, and instability. The patient is placed either in the lateral position with all bony prominences well padded, with the shoulder in 30° of abduction and 15° of forward flexion, or in the beach-chair position with suspension traction. The arm is suspended with 3 kg of distal traction. After surgical draping, a standard posterior viewing portal is established, approximately 1 cm medial and 2 cm inferior to the posterolateral acromial edge in the “soft spot.” A thorough diagnostic evaluation is then performed. The Bankart lesion is identified and all other pathology acknowledged, including associated capsular tears, humeral avulsions of the glenohumeral ligament (HAGLs), bony defects on the glenoid rim and humeral head, and rotator cuff and biceps injuries. An 18-gauge spinal needle is used for assessment of the appropriate angle of approach, and an anterior portal is created through the rotator interval. A working arthroscopic cannula is inserted for safe instrument exchange. The Bankart lesion is thoroughly elevated from the glenoid neck (Video 1). A grasping tool is used to evaluate whether the tissue can then be shifted in an inferior-to-superior direction to correct the ligament attenuation. The glenoid rim is gently prepared with a shaver. Lifting the humeral head off of the glenoid plateau is established with some leverage under the axilla from outside the joint, besides the traction. For a safe approach to the most inferior capsulolabral junction and the axillary pouch, an API portal is established; in line below the lateral tip of the acromion and 2 to 3 cm distal to the posterior viewing portal, an 18-gauge needle is introduced (Fig 1, Video 1). It is good practice to press the skin while visualizing with the arthroscope to ascertain the safe and convenient placement of the needle. The surgeon should use the spinal needle as a guide, making sure that a linear approach to the anteroinferior part of the capsule is possible. The needle courses medially to the convex retracted humeral head and continues anteriorly to the lower anterior gutter and capsulolabral junction (Fig 1B). With the spinal needle left in place inside the joint, a small incision is made in the skin adjacent to it, and a slotted cannula (FAST-FIX Meniscal Repair System; Smith & Nephew, Andover, MA) (Fig 2) is slid along it into the joint, just avoiding the humeral head. This ensures the safe course of the blunt slotted cannula and prevents accidental poking of the inferior soft tissues, along with the axillary nerve (Fig 1C). The spinal needle is removed, and working tools can be exchanged over the slotted cannula (Fig 1D and E). The slotted cannula helps maintain direct working access to the IGHL, facilitates more rapid instrument exchange, and reduces trauma to the soft tissues during instrument exchange. A curved suture penetrator loaded with a No. 2 FiberWire (Arthrex, Naples, FL) (or other strong suture) is passed through the lowest aspect of the IGHL. A suture manipulator inserted from the anterior portal is used to apply tension to the IGHL as the suture-loaded penetrator pierces through it from the API portal (Fig 1F, Table 2). This allows bimanual control of the most crucial step of the procedure—optimal suture location for adequate tissue shifting, as well as a lateral-to-medial closure. Once pierced through the IGHL, the manipulator is used to withdraw the suture from the penetrator, loop the suture over the IGHL, and pull both limbs through the anterior working portal. Using the suture to pull the IGHL upward, the surgeon determines the proper location for anchor placement and places a drill hole for the anchor on the glenoid face, 2 to 3 mm onto the articular surface. A knotless anchor (PushLock Knotless; Arthrex) is used to attach the IGHL onto the glenoid face. An additional 1 to 2 anchors are used to complete labral fixation and restore the labral height, thereby re-establishing glenoid depth.

Fig 1.

Surgical technique for safely applying the API portal during arthroscopic Bankart repair, allowing one to reach the most inferior capsulolabral junction and the axillary pouch. (A) Surface anatomy (right shoulder, lateral decubitus patient positioning with lateral traction) showing location of API portal. One should note the anatomic location below the tip of the acromion 2 to 3 cm inferior to the posterior viewing portal. (B) Probing with an 18-gauge spinal needle (right shoulder, arthroscopic view from posterior viewing portal). One should note the optimal reach and trajectory of the needle toward the axillary pouch and the inferior capsulolabral junction, as well as the anteroinferior labrum. (A, C) The slotted cannula is slid over the spinal needle; sliding it tightly adjacent to the needle ascertains a safe track into the joint. (D) Tool exchange with spinal needle over slotted cannula. (E) Access and manipulation of lowest capsulolabral tissue. (F) Suture passage and collection while maintaining traction of tissue from posteroinferior portal.

Fig 2.

Slotted cannula from FAST-FIX Meniscal Repair System for safe tool exchange using API portal.

Table 2.

Tips and Pearls for Safely Reaching Most Inferior Capsulolabral Junction While Arthroscopically Repairing Bankart Lesion or HAGL or Performing Inferior Capsular Plication Using API Portal With Slotted Cannula

Identify the surface anatomy.

Position the API portal 2 to 3 cm below the posterior viewing portal (Fig 1A).

For positioning of the API, either perform an inside-to-outside technique using a switching rod or perform an outside-to-inside technique.

Use a spinal needle to probe from the outside in, under vision, with the arthroscope angle directed distally and posteriorly (Fig 1B).

Ensure some exterior axillary leverage, in addition to lateral traction, to lift the humeral head away from the glenoid.

Probe with the tip of the spinal needle to ensure optimal access and reach.

With a small skin incision, slide a slotted cannula along the spinal needle (Fig 1C).

Over the slotted cannula, slide a manipulator to mobilize the anteroinferior capsule and labrum (Fig 1D).

Use an assistant to direct the arthroscope while working from the anterior and API portals.

The postoperative rehabilitation protocol consists of use of a shoulder immobilizer in neutral rotation for 6 weeks. Patients are allowed to remove the immobilizer for “controlled” activities of daily living, such as eating, showering, and using a computer. At 3 to 4 weeks postoperatively, dangling exercises are initiated, and 1 to 2 weeks later, active-assisted motion followed by active range of motion is initiated. Ninety percent of motion should be recovered by 12 weeks. Combined abduction and external rotation exercises are started at 12 weeks, and a return to unrestricted activities, including contact or collision sports, is permitted at 6 months postoperatively.

Discussion

Patients with symptomatic recurrent anterior shoulder instability in whom nonoperative management has failed are often offered surgical stabilization. No consensus has been achieved on the surgical approach to chronic shoulder instability. A recent systematic review showed that arthroscopic suture anchor and open Bankart techniques yield similar long-term clinical outcomes.¹ Arthroscopic treatment offers the advantage of a minimally invasive approach with less soft-tissue scarring, restriction in motion, and subscapularis failure.^11,15,20

The anterior portal is the traditional gold standard for elevation of the Bankart lesion from the glenoid neck, anchor insertion, and manipulation and fixation of the IGHL to the glenoid rim.^3,15,21 However, access to the most inferior part of the IGHL is sometimes challenging using the anterior portal because of the convexity of the humeral head, which blocks the direct instrumental line. The ability to adequately tension the IGHL for optimal suture placement is limited using this working portal.¹⁷

Access solutions to the inferior glenohumeral zone include lower portals, which are in proximity to delicate anatomic structures: the axillary artery; the axillary nerve and its branch to the teres minor muscle; the suprascapular nerve; and nearer to the coracoid process and the conjoined tendon, the neurovascular bundle from the brachial plexus. Anteroinferior portals are in use for that purpose and, when established correctly under vision, are efficient and safe.^22-24 The disadvantages are the need to work very close to the portal's orifice, which can lead to work in acute angles and drive the instruments in the lower part of the pouch. Table 1 shows advantages and challenges of using the API portal.

By using the API portal, easier access is gained to the inferior part of the joint and the IGHL. Structures at potential risk from use of the posteroinferior portal include the branches of the suprascapular nerve and its artery; the axillary nerve, which courses with the posterior circumflex humeral artery; and the articular surfaces of the humerus and glenoid.¹⁸

Difelice et al.¹⁷ measured the distance of the axillary and suprascapular nerves from the API portal with patients both in the beach-chair position and in the lateral position. They found it to be a safe portal, measuring 2 cm, on average, from the axillary nerve at the 8- or 4-o’clock position. Davidson and Rivenburgh¹⁸ described the 7-o’clock posteroinferior portal and, in a cadaveric study, showed it to be at a safe distance as long as the access to it is established under visualization with a spinal needle, as is described in our technique. In another anatomic research study, Bryan et al.²⁵ showed that the mean distance of an accessory posterior portal from the axillary nerve was approximately 1.89 cm.

The API portal enables working from a convenient angle to the anteroinferior capsulolabral junction. The use of a spinal needle helps in locating the accessory posterior portal by an optimal access route to the lowest part of the capsulolabral complex. It also enables a firmer grasp and mobilization of the tissue, quick and easy tool exchange using a slotted cannula, and clearer suture placement because of the flat, direct working angle. The skin incision is made small without the need for arthroscopic cannula, and the portal location is in a relatively safe zone.

Using a narrow slotted cannula gives the advantages of a small incision, accurate direction of manipulation tools and suture placement, and easy and safe tool exchange while maintaining the safe root open; thus it shortens the duration of the operative procedure and improves performance. It prevents accidental poking inside the soft tissues in the vicinity of the portal, for example, the axillary nerve.

Patients rarely are believed to have unidirectional instability, but recognition of the full spectrum of instability, which can include elements of multidirectional instability (MDI), has become more prevalent. Patients with MDI present with instability of the shoulder in several planes of motion.^8,26,27 Surgical treatment consists of inferior capsular shift, usually performed by an open method. Arthroscopic capsular plication yields comparable results to open capsular shift with regard to recurrent instability, return to sport, loss of external rotation, and overall complications.²⁶ The API portal allows direct access to and manipulation of the inferior capsule (Table 3). In addition, this accessory portal facilitates performing an anterior and posterior pan-capsular plication in MDI cases. In the case of an engaging Hill-Sachs lesion, the API portal allows abrasion of the lesion, anchor placement, and remplissage,²⁸ in addition to the Bankart repair (Video 1).

Table 3.

Possible Indications for Placement of API Portal

Arthroscopic Bankart repair with low-reaching labral detachment

Inferior capsular laxity for both unidirectional instability and MDI

Engaging large Hill-Sachs lesion for remplissage

HAGL

Unicameral bone cyst curettage32

Access to superior labrum (SLAP repair)

Another subtype of shoulder instability that can be repaired by use of the API portal is humeral avulsion of the inferior glenohumeral ligament (HAGL). HAGL lesions are considered among the most difficult lesions to address arthroscopically. The API portal can be used to ensure anatomic placement of the suture anchor within the insertion site of the IGHL on the humeral head^29-31 (Fig 3). Randelli et al.³² have reported on arthroscopic curettage of a unicameral bone cyst, in which access was enabled through the API portal.

Fig 3.

(A) Arthroscopic access to HAGL lesion using API portal. The HAGL lesion is identified. The muscle striation of the subscapularis should be noted. (B) Humeral anchor placement using API portal and slotted cannula. (C) Reduction of HAGL lesion by suture anchor.

To conclude, we present an arthroscopic technique for Bankart repair using the API portal for direct and easy access to the IGHL. Further advantages include improved access to deal with various other pathologies, which may enable improved repairs (Table 1). Overall, this novel technique for inferior capsulolabral access provides a successful and reproducible tool for arthroscopic repair of a number of shoulder pathologies.

Supplementary Data

Video 1

The arthroscopic technique for Bankart repair and Hill-Sachs remplissage is described with an emphasis on the use of the API portal with a spinal needle and a slotted cannula (Fig 2) for safe and easy access to the lower capsulolabral junction.