Arthroscopic Revision of Medial Rotator Cuff Failure Augmented With a Bioabsorbable Patch

We prefer the beach-chair position and use a custom-made soft tissue traction system with 2 kg that maintains the arm in loose anteversion of 30° to 40° allowing free rotation (Fig 1). The patient routinely receives general anesthesia combined with an interscalene block for better intraoperative monitoring of blood pressure and postoperative pain control. After skin marking of the osseous landmarks, we proceed to diagnostic arthroscopy and portal placement. Apart from the posterior standard portal, we routinely use 4 portals: an anterosuperior, anterolateral, lateral, and posterolateral portal. A soft Passport cannula (Arthrex, Naples, FL) measuring 40 mm in length and 8 mm in diameter is placed in the lateral portal for RC refixation, and a second one in the anterosuperior portal is added for patch augmentation. Additional percutaneous portals are applied as needed for suture management.

The glenohumeral phase most importantly includes—even for small partial tears—repair of the subscapularis (performed in approximately 1/3 of cases). The suture limbs closest to the comma sign are left uncut for later integration into the SB. After removal of loose suture material (Video 1), we carefully inspect the articular side of the supra- and infraspinatus and confirm (partial) healing at the footprint and a medial defect as the criteria of a medial RC failure. Then, we proceed to footprint preparation with an aggressive shaver blade paying attention not to disturb healed areas of cuff insertion. As a result, we frequently encounter a facet of bleeding bone with a diameter of approximately 1 cm. Next, bone marrow stimulation should be performed with the preferred device. Before leaving the joint space, we visualize the posterior cuff from the anterosuperior portal paying attention to delamination of the infraspinatus with retraction of its deep layer.

The arthroscope is now switched into the subacromial space (Video 1), where we proceed to bursectomy and sparse debridement of the cuff margins (Fig 2A) in the centrally torn or weak zone. Loose suture material of the lateral row is removed and an additional acromioplasty performed as needed. With the arthroscope in the lateral portal, extensive bursectomy is performed starting in the lateral gutter and then moving posteriorly. The posterior cuff is carefully checked for tissue quality and for delamination again. With the long-curved straight Spectrum device (Linvatec, Utica, NY), 2 side-to-side margin-convergence stitches (typically PDS No. 1, Ethicon, Somerville, NJ) are placed at the apex of the defect and left untied. Now a triple-loaded anchor (PEEK [polyether ether ketone] or biocomposite), for example, Healicoil (Smith & Nephew, Memphis, TN), is inserted into the subchondral bone at the articular margin of the footprint (Fig 2B). Bone quality is uniformly good here and we are not worried about anchor pullout. Curved suture retrievers (e.g., Clever Hook, DePuy Mitek, Raynham, MA) are well suited for rapid suture passing anteriorly and posteriorly. Typically one posterior mattress stitch shifts the retracted deep posteromedial layer of the infraspinatus superiorly; the remaining 2 work as “margin-convergence-to-bone” stitches including both the anterior and posterior cuff. All sutures are now tied with sliding knots, the side-to-side sutures cut, and the anchor sutures left long for crossed SB configuration (Fig 2C) with 2 lateral push-in anchors (e.g., PushLock, Arthrex). These are placed approximately 1.5 cm laterally from the apex of the greater tuberosity for better bone quality. The anterior PushLock is inserted directly adjacent to the sulcus, and the second one 2 to 2.5 cm more posteriorly using internal rotation of the arm. Two suture tails per anchor are left uncut (Fig 3).

In the next step, patch augmentation of the repaired RC is performed (Video 1). The synthetic 2 × 3 cm scaffold (BioFiber, Tornier, Bloomington, MN) is prepared by the assistant on the side table, who places 2 PDS shuttle sutures in the lateral edges 3 to 5 mm from the margin. Simultaneously, the surgeon places 2 long nonabsorbable sutures (e.g., Orthocord, DePuy Mitek) at the musculotendinous junction 1.5 to 2 cm apart intended for pulling in and medial fixation of the patch. For this purpose, we like to use the 45° curved Spectrum device with a PDS shuttle. The location of these stitches is perpendicular to the acromioclavicular joint; the distance between them is measured with a calibrated probe and should add up to 1.5 to 2 cm. With a free needle the medial corners of the scaffold are pierced and secured with one half hitch extra-articularly (Fig 4A). We use these sutures to pull the “flying carpet” into place (Fig 4B). The patch bends easily and can be molded as a “half pipe” permitting easy passage through the 8-mm Passport cannula. Now we tie the medial knots through the anterior cannula using nonsliding double square knots (Fig 4C).

After medial attachment, we proceed to lateral fixation (Video 1) of the patch using the leftover suture limbs from the lateral anchors that are shuttled through the lateral corners with the previously placed PDS shuttle sutures and tied as double square knots (Fig 5A) applying some tension in approximately 30° of abduction of the arm (Fig 5B). Fixation is completed with PDS No. 1 sutures on the long sides of the patch anteriorly and posteriorly. This is easily achieved with “direct shots” using the straight-curved Spectrum device (Fig 5C). The final aspect shows neat unfolding of the patch over the weak area in the center of the cuff (Fig 6; Table 1).

Medial failures represent a potential feature of revision RC repair. Tissue quality is often suboptimal, so patch augmentation becomes a logically desirable adjunct.^,  The proposed scaffold (BioFiber, Tornier) has good mechanical stability, retains 50% to 70% of strength at 3 months, and should be fully absorbed after 18 months. The biosynthetic fibers from poly-4-hydroxy-butyrate are subject to slow degradation in the Krebs cycle breaking down into naturally occurring metabolites, eliminated without toxicity. They are woven into a bilayer lattice structure that allows for cellular ingrowth. Passing of stitches with suture hooks is easy and costs are much lower as compared with commonly used matrices such as human dermis allografts. The size of the patch of 3 × 2 cm is ideal for most situations; trimming is avoided, as this would mechanically weaken the scaffold. By applying tension on the lateral corners theoretically a load sharing effect to the underlying cuff tissue should be obtained.

The material has been successfully used in general surgery (abdominal wall hernias) and cosmetic breast surgery; however, only few preliminary communications are available in the orthopaedic literature. Figure 7 was obtained at arthroscopic evaluation of the patch 6 months postoperatively and revealed its unproblematic ingrowth.

This technique complies with all advantages of a fully arthroscopic technique including less postoperative pain, better cosmesis, and favorable patient acceptance. Following a systematic step-by-step suture management (Table 2), patch augmentation adds only approximately 30 minutes to the operating time. No additional bone anchors are needed for patch fixation making this procedure cost-efficient (Table 3).