The Use of All-Arthroscopic Autologous Matrix-Induced Chondrogenesis for the Management of Humeral and Glenoid Chondral Defects in the Shoulder

Abstract

Autologous matrix-induced chondrogenesis (AMIC) is often used for treating chondral defects in different joints. We describe an all-arthroscopic approach for the treatment of glenoid and humeral chondral lesions with this technique. AMIC starts with the use of microfractures of the damaged cartilage, followed by coverage of the defect with a type I/III collagen matrix (Chondro-Gide; Geistlich Pharma, Wolhusen, Switzerland) that is fixed with fibrin glue (Tissucol; Baxter, Warsaw, Poland). In a 1-step approach, the unstable cartilage is debrided, microfractures that penetrate up to the subchondral bone are performed, and the membranes are pasted to the lesion. Our technique reduces morbidity rates compared with traditional open surgery. The arthroscopic AMIC procedure is a viable, cost-effective treatment for the repair of chondral lesions of the shoulder.

Chondral defects are an uncommon cause of pain and dysfunction of the shoulder. They have been historically underdiagnosed, and the true incidence is not well-known. These lesions are usually diagnosed during surgery for other concomitant lesions, and they appear not to be so uncommon.1, 2, 3 Although many lesions do not cause problems and are considered asymptomatic, some lesions, especially larger lesions in young people, present a treatment challenge.

Many treatments have been described to try to repair chondral defects: simple debridement, microfracture, autologous chondrocyte implantation (ACI), matrix-induced ACI, autologous stem cell transplantation, allograft transplantation, autologous matrix-induced chondrogenesis (AMIC), or hyaluronic acid–based scaffold implantation (Hyalofast; Anika Therapeutics, Bedford, MA). AMIC was described in 2010.4, 5 This technique consists of placing a collagen matrix (porcine type I and III collagen [Chondro-Gide; Geistlich Pharma, Wolhusen, Switzerland]) fixed with fibrin glue (Tissucol; Baxter, Warsaw, Poland) over the cartilage defect that has previously undergone microfracture. The collagen membrane serves as a scaffold for the local cells to reconstruct the damaged cartilage surface.6, 7 The advantages of this technique are the easy implantation of the membrane, the avoidance of a second operation, and the price, because it is not as expensive as other biological techniques.

The use of AMIC has gained increasing popularity for the treatment of chondral lesions in the knee, hip, and talus.8, 9, 10, 11, 12 Performing the AMIC technique with an all-arthroscopic technique decreases the risk of infection, risk of wound morbidity, and operative time. In this report an all-arthroscopic technique to perform AMIC on both the humeral and glenoid sides of the glenohumeral joint is presented.

Surgical Technique

The patient is placed in the lateral decubitus position. The glenohumeral joint is accessed through the posterior portal, and an anterior portal and anterosuperior portal are created in the rotator interval (Fig 1). The first step is to define the size and depth of the chondral lesion on the glenoid or humerus surface because AMIC is indicated for grade III or IV chondral lesions that have a surface area of 2 to 8 cm². If the humeral chondral cartilage lesion is very posterior, external rotation of the arm allows for better lesion exposure. If there are associated lesions that have to be dealt with, such as rotator cuff tears or Bankart lesions, the chondral repair procedure is left aside to be performed at the end of the surgical procedure.

Fig 1.

Arthroscopic access portals for shoulder: anterior portal (a), anterosuperior portal (as), and posterior portal (p). A right shoulder is shown.

The fibrous tissue and unstable cartilage are debrided from the glenoid and the humerus with 40° and 70° open curette instruments (Smith & Nephew, Andover, MA) and a 4.5-mm full-radius motorized shaver with a disposable blade (Smith & Nephew) (Fig 2A); because it is essential to adequately expose the subchondral bone, the margins of the chondral lesion should be clean and uniform. Then, microfractures that penetrate up to the subchondral bone are performed with a 60° Steadman-like microfracture pick (Chondral pick; Smith & Nephew); the result must be linear strips of 2 mm thickness (Fig 2B). The optic is shifted to the anterosuperior portal because both the posterior and anterior portals can be used to place and manipulate the membranes. It is important to place a cannula (8.5 mm × 72-mm Clear-Trac Complete cannula; Smith & Nephew) in the posterior portal with the aim of placing the membranes through it with minimal damage to the delicate collagen mesh.

Fig 2.

A glenoid chondral defect in a patient with right shoulder instability (posterior portal view with 30° arthroscope). (A) The fibrous tissue and unstable cartilage are debrided with curettes and motorized shavers to expose the subchondral bone of the glenoid. (B) Linear strips are then made using arthroscopic Steadman microfracture awls.

The next step is precisely measuring the size and shape of the defect; this is best performed using a centimeter-marked needle or comparing the lesion with the shaver tip. The use of an aluminum template (Geistlich Pharma) that can be placed into the joint with care can be helpful in complex-shaped lesions. The Chondro-Gide matrix (Geistlich Pharma) is then cut to the desired shape and size; the surgeon should take into account that it increases 10% in size when moistened, so a small amount of undersizing is recommended. The porous layer of the membrane must be placed facing the bone, so it is useful to mark the upper side of the membrane with a pen.

The next part of the procedure, pasting the membranes to the lesion, should be performed without liquid in the joint: The saline solution irrigation is interrupted, and the glenoid lesion bed is dried by shaver aspiration and suction through a spinal needle. We recommend positioning the membrane in the glenoid lesion first, because gravity tends to keep it in place, so it is easier (Table 1). First, biological fibrin glue (Tissucol; Baxter) is applied over the lesion bed of the glenoid through a spinal needle. The glenoid matrix is delivered into the joint through the posterior cannula and positioned in the glenoid lesion (Fig 3, Video 1); it must be slightly undersized with respect to the intact cartilage to avoid shoulder movements taking off the membrane. When the matrix is correctly placed, it is useful to add more fibrin glue on the edges of the matrix with the aim of ensuring appropriate fixation.

Table 1.

Key Points of Arthroscopic Autologous Matrix-Induced Chondrogenesis Technique in Glenohumeral Joint

Place the patient in the lateral decubitus position.

Develop the posterior, anterior, and anterosuperior portals.

Identify the lesions and debride them of fibrous tissue and unstable cartilage.

Make linear strips in both lesions.

Measure the lesions.

Carefully dry the joint space.

Add fibrin glue in the glenoid chondral lesion.

Insert the matrix through the posterior cannula.

Position the matrix in the glenoid lesion.

Add fibrin glue in the humeral chondral lesion.

Insert and position the other matrix in the humeral lesion.

Place and inflate the Foley catheter balloon into the joint.

Remove the Foley catheter, and check the stability of the matrix during shoulder movements.

Fig 3.

Placement of glenoid membrane (anterosuperior portal view with 30° arthroscope in right shoulder). The glenoid membrane (gm) is positioned over the glenoid lesion (asterisk).

Then, attention is drawn to the humeral defect. Correctly placing the matrix at the humeral defect is more difficult because it is against gravity, given that the patient is in the lateral decubitus position. First, a good layer of fibrin glue is placed in the humeral chondral lesion with the spinal needle, and then, the matrix is delivered into the joint through the posterior portal (Table 1). With the help of a blunt-tipped device inserted through the anterior portal, the matrix is fixed in one corner of the defect (Table 2); then, delicately using a cuff grasper (Elite Premium Alligator Locking Grasper; Smith & Nephew), the surgeon spreads the rest of the matrix over the chondral defect (Fig 4, Video 1). Again, it is recommended to place fibrin glue at the edges of the matrix after initial placement. A Foley catheter balloon (Teflon; DuPont, Geneva, Switzerland) is inserted into the joint through the cannula and is inflated to compress the membranes for 5 minutes (Fig 5A).10, 13 The Foley catheter is then removed carefully. Finally, the joint is wholly assessed and the implants are evaluated while rotatory and flexion-extension movements are performed (Fig 5B, Video 1).

Table 2.

Pearls and Tips of Arthroscopic Autologous Matrix-Induced Chondrogenesis Technique in Glenohumeral Joint

The defect surface has to be completely dry. The surgeon should use a spinal needle to aspirate any remaining liquid at the defect.

The surgeon should use an arthroscopic cannula to avoid damaging or deteriorating the membrane during passage into the joint.

The humeral membrane has to be placed on the defect against gravity; folding and wrinkling of the membrane can easily occur during this step. The surgeon should focus on fixing 1 of the corners of the membrane with fibrin glue and then spread the rest of the membrane.

To keep the membranes in place, the surgeon should add generous amounts of fibrin glue at the edges and use a Foley balloon to compress the membranes in place.

Fig 4.

Placement of humeral membrane (anterosuperior portal view with 30° arthroscope). The humeral membrane (hm) is positioned over the humeral lesion with the help of a blunt-tipped device (Bt) from the anterior portal that fixes one corner of the matrix against the humeral lesion; then, with the help of a grasper from the posterior portal (Pp), the membrane is attached over the chondral defect.

Fig 5.

Final placement of matrix (anterosuperior portal view with 30° arthroscope). (A) A Foley catheter balloon (f) is placed into the joint through the posterior cannula and is then inflated. The asterisks indicate the matrixes. (B) After removal of the Foley catheter, the placement of the matrixes (asterisks) can be fully assessed. (Hu, humerus chondral surface.)

Discussion

This technical note describes an all-arthroscopic method to apply the AMIC technique in the glenohumeral joint. The main advantage of our technique is that it allows for complete arthroscopic management of glenohumeral chondral lesions.

Cartilage lesions of the glenohumeral joint can be effectively treated with arthroscopic microfracture¹⁴; therefore, because the AMIC technique is based on the microfracture technique in the knee described by Steadman et al.,¹⁴ it may be of use as a further restorative treatment.¹⁵ This technique relies on a combination of collagen and hyaluronic acid membranes and microfractures that provide a stable matrix that allows for cellular proliferation and differentiation.⁷ The AMIC technique has an advantage over isolated microfractures in that it provides a scaffold for cell development and differentiation; therefore, the resulting cartilage has better features than fibrocartilage.

Use of AMIC in the glenohumeral joint is considered investigational, and experience is very limited in this application. Thus clinical studies are necessary to establish whether the AMIC technique offers better functional outcomes than isolated microfractures.¹⁴ ACI techniques are effective treatments for chondral and osteochondral lesions,¹⁶ but the use of the AMIC technique in a single procedure has facilitated its arthroscopic application. ACI requires 2 procedures, an open operation, and significant laboratory infrastructure, and it is more expensive. On the other hand, shoulder arthroplasty provides excellent pain relief, but in young people, the implants have a limited lifespan.

There are reports on the treatment of cartilage lesions using AMIC techniques arthroscopically,9, 10, 11, 12, 13 but not in the shoulder. It must be taken into account that the shoulder differs from the hip, knee, and ankle in some ways regarding the AMIC procedure: The glenohumeral joint is a non–weight-bearing joint; it also has thinner cartilage and is not so constrained. Despite these differences, given the reported results with the use of AMIC in the knee,⁵ we think that the AMIC technique can contribute to shoulder chondral lesion repair because it is a nonaggressive treatment that is relatively easy to perform and does not hinder subsequent resurfacing or reconstructive surgical procedures. Despite its simplicity, this technique requires the surgeon to take into account some tricks to avoid prolonging the surgical procedure (Table 2). Therefore AMIC may be an effective tool in managing painful glenohumeral cartilage lesions and delaying open surgical procedures, which imply greater postoperative risks, such as infection, blood loss, avascular necrosis of the humeral head, and a longer recovery time. However, as other authors have noted, the all-arthroscopic AMIC technique can be associated with some complications (collagen allergy, matrix detachment or mobilization, hyper-proliferative healing reaction, and the complications of shoulder arthroscopy).12, 17

In our limited experience with the described technique, magnetic resonance imaging control scans have allowed us to confirm the stability of the implanted membranes (2- and 7-month magnetic resonance imaging scans). It is possible to apply the AMIC technique all-arthroscopically in the glenohumeral joint, allowing an easy approach to the articular surface for application of matrixes on the humeral and glenoid surfaces.

Supplementary Data

Video 1

With viewing from the anterosuperior portal with a 30° arthroscope, the unstable cartilage is debrided and linear strips are made. Fibrin glue is applied into the glenoid and humeral lesions for stabilization of the autologous matrix-induced chondrogenesis membranes. Finally, a Foley catheter balloon is inserted into the joint and is inflated to compress the membranes.