- Email: [email protected]
Double-Row Suture-Bridging Arthroscopic Rotator Cuff Repair
Double-Row Suture-Bridging Arthroscopic Rotator Cuff Repair Patrick J. Denard, MD,*,† and Stephen S. Burkhart, MD‡ Rotator cuff repair has undergone a paradigm shift over the past 2 decades in which open approaches have largely been replaced by arthroscopic techniques that restore anatomy in a minimally invasive fashion. The evolution of knotless anchors in particular has allowed the development of suture-bridging double-row repair constructs that maximize footprint restoration and fixation strength. Suture-bridging constructs appear to have substantially improved tendon-healing rates compared with single-row repair. This article highlights the rationale for double-row suture-bridging rotator cuff repair and describes our technique for maximizing restoration of anatomy with these constructs. Oper Tech Orthop 23:84-90 C 2013 Elsevier Inc. All rights reserved. KEYWORDS suture-bridging, double-row, arthroscopic rotator cuff repair
R
otator cuff repair has undergone dramatic advancements over the past 2 decades, progressing from extensile open repairs to arthroscopic repairs that can be performed in a minimally invasive fashion while maximizing restoration of the anatomy. Initially, arthroscopic rotator cuff repair (ARCR) was performed with a single row of medial anchors. Doublerow repairs evolved as surgeons attempted to achieve more anatomical rotator cuff repairs. In an effort to improve footprint restoration and biomechanical strength, repairs have transitioned from a nonlinked double-row repair to a suture-bridging double-row repair. This review highlights our rationale for suture-bridging double-row ARCR and describes our current technique for repair of a standard medium-sized crescent-shaped tear.
Rationale for Double-Row Repair Biomechanically, the goal of a rotator cuff repair is to achieve high initial fixation strength, minimize gap formation, and maximize contact area. In other words, although biology plays an important role in rotator cuff tendon healing, biomechanical factors must be optimized by the surgeon at time zero to provide the best chance for tendon healing. *
Southern Oregon Orthopedics, Medford, OR. †Department of Orthopaedics and Rehabilitation, Oregon Health & Science University, Portland, OR. ‡The San Antonio Orthopaedic Group, San Antonio, TX. Address reprint requests to Stephen S. Burkhart, MD, 150 E Sonterra Blvd, Suite 300, San Antonio, TX 78259. E-mail: [email protected]
84
1048-6666/13/$-see front matter & 2013 Elsevier Inc. All rights reserved. doi:http://dx.doi.org/10.1053/j.oto.2013.05.005
The traditional double-row repair consisted of independent rows of medial and lateral anchors in which the medial sutures were placed as mattress stitches and the lateral sutures were placed as simple sutures.1 This repair improved footprint restoration,2 and fixation strength as compared with singlerow repairs.3,4 The advancement of knotless suture anchors not only simplified the technical demand of ARCR, but more importantly allowed the creation of suture-bridging constructs whereby the medial and lateral rows are linked (Fig. 1). Suturebridging repairs, which link the 2 rows, have improved pressurized footprint contact area and ultimate load to failure compared with a traditional double-row repair.5,6 Moreover, because the medial and lateral rows of the suture-bridging double-row repair are linked, the construct exhibits selfreinforcing properties much like a Chinese finger trap (Fig. 2).7 Although there has been some debate in the literature about clinical outcomes after single-row repair vs double-row repair, several key factors should be considered, and they have been briefly discussed here. For a more extensive review of this debate, the reader is referred elsewhere.8 The initial studies reported on short-term functional outcome of single-row repairs compared with a traditional nonlinked double-row repair.9-11 With patient cohorts between 40 and 80 patients, these studies were underpowered to detect differences between the 2 groups. Meta-analysis, however, has revealed that healing rates are improved with double-row repairs. Duquin et al12 reviewed 23 articles with a total of 1252 rotator cuff repairs. In their pooled analysis, the recurrence rate for tears ≤3 cm was 19% following single-row repair compared with only 7% following double-row repair. For tears larger than 3 cm, the
Arthroscopic rotator cuff repair
85
Figure 1 Comparison of traditional double-row repair and suture-bridging double-row repair. (A) With the original doublerow rotator cuff repair, 2 medial anchors were placed, sutures were individually passed and tied as mattress stitches, and then the suture limbs were cut. Two lateral anchors were also placed, sutures were passed and tied as simple stitches, and the suture limbs were cut. (B) In a suture-bridging double-row repair, the medial and lateral rows are linked. Two medial suture anchors are placed and sutures from these anchors are individually passed and tied as mattress stitches. Rather than cutting the suture limbs however, the sutures are crisscrossed and secured laterally to 2 knotless anchors. This repair mechanically links the 2 rows and provides enhanced footprint compression to encourage rotator cuff healing. Reproduced with permission from Burkhart SS, Lo IK, Brady PC, et al: The Cowboy’s Companion: A Trail Guide for the Arthroscopic Shoulder Surgeon. Philadelphia, Lippincott, Williams, & Wilkins, 2012. (Color version of figure is available online.)
retear rate increased to 45% following single-row repair vs 26% following double-row repair. These improved healing rates are important given that13,14 healing is associated with a superior functional outcome at midterm and long-term follow-up. Moreover, as opposed to the short-term follow-up (1-2 years) of the aforementioned studies, long-term follow-up has demonstrated that functional outcome is also superior following a
double-row repair compared with a single-row repair. Denard et al,15 for instance, demonstrated that a traditional double-row repair of a massive tear was 4.9 times more likely to lead to a good or excellent functional outcome compared with a singlerow repair at a mean of 99 months postoperatively. Excellent outcomes of suture-bridging double-row repairs have also recently been reported in several clinical studies.
Figure 2 Schematic of self-reinforcing suture-bridge technique. (A) Linked double-row construct before loading. Inset: Freebody diagram of the construct. H1, thickness of rotator cuff before loading; L1, length of tendon beneath suture. (B) Loading of the linked double-row construct results in compression of the rotator cuff footprint. Inset: Free-body diagram of the construct. T, tensile loading force; L2, length of tendon beneath suture; a, length of suture between tendon edge and lateral anchor; H2, thickness of compressed rotator cuff under tensile load. (C) Up close view of the linked double-row construct after loading. Inset: Free-body diagram showing distributed normal force (N) resulting from elastic deformation of tendon beneath the suture. The frictional force (f) increases as the normal force (N) increases under load. (D) Linked double-row construct with 2 medial anchors linked to 2 lateral anchors provides maximal footprint compression under loading. Additionally, a medial double mattress stitch in this case provides a seal to joint fluid. Reproduced with permission from Burkhart SS, Lo IK, Brady PC, et al: The Cowboy’s Companion: A Trail Guide for the Arthroscopic Shoulder Surgeon. Philadelphia, Lippincott, Williams, & Wilkins, 2012. (Color version of figure is available online.)
P.J. Denard and S.S. Burkhart
86 Frank et al16 reported an 88% rate of healing in 25 rotator cuff tears repaired with a suture-bridging construct. Toussaint et al17 reported on 154 repairs and observed a 92% rate of healing in small tears as well as an impressive 84% rate of healing among massive tears. Other studies have demonstrated similarly high rates of healing.18-21 Based on these improved healing rates, in our opinion, a suture-bridging double-row repair is the current standard of care for rotator cuff repair.
Surgical Technique In the setting of sufficient tendon mobility, we always perform a suture-bridging repair of medium-sized crescent tears. However, if there is insufficient tendon mobility or tendon loss such that pulling the tendon to the lateral part of the tuberosity would result in overtension of the repair, we do not do a footprint reconstruction. Tissue quality also influences the types of suture-bridging repairs that we perform. For goodquality tissue, we use a knotless SpeedBridge technique with FiberTape and 2 rows of BioComposite SwiveLock-C suture anchors (Arthrex, Inc, Naples, FL). For fair-quality tissue, we utilize a SpeedBridge repair augmented with a medial double mattress suture (double-pulley technique22) as medial mattress sutures enhance the fixation of a knotless repair.23 If the tissue quality is poor, we use more suture passes through the tendon and more knots to strengthen the construct (SutureBridge; Arthrex, Inc). In addition, in keeping with our opinion that the anatomy should be restored as closely as possible, we make every effort to restore the natural rotator cable insertions by placing independent sutures to reinforce the rotator cable attachments at the anterior and posterior margins of the repair. These independent cinch-loop sutures also serve to reduce the dog-ears that typically appear at the anterior and posterior margins of the footprint repair. In the following section, we describe our technique for a SpeedBridge repair (Fig. 3). However, the steps for a SutureBridge repair are essentially the same, with the exception that more suture passes are performed medially and all sutures are tied before linking the sutures to the lateral row.
Prepare the Soft Tissues and Bone Bed Following diagnostic arthroscopy, the soft tissues and bone bed are prepared for repair. A complete bursectomy is performed, allowing the surgeon to see the entire margin of the cuff tear. This is essential, because you must clearly see the tendon so as to accurately repair it. Secondly, it removes the potentially harmful degradative enzymes that reside in the subacromial bursa. In addition to the bursectomy, the surgeon must debride any bursal leaders that attach to the internal deltoid fascia, and he must debride friable tendon edges while retaining robust tendon even if it appears poorly vascularized. Bone bed preparation is critically important to achieving tendon-to-bone healing. Soft tissue is removed from the greater tuberosity with an electrocautery (which creates a charcoallike film on the bone surface) and then a high-speed burr is applied to lightly “burr off the charcoal.” It has been shown that the
greatest blood supply for rotator cuff healing comes from the bone.24 Furthermore, although some have raised the concern that compression from a suture-bridging repair would decrease blood flow to the tendon, it has been shown that blood flow to the tendon is preserved with this type of repair.25 To enhance the amount of blood and bone marrow products that reach the tendon-bone interface, we also prefer to use vented suture anchors that have side vents in addition to the longitudinal cannulation through which blood products from the bone marrow can reach the repair interface at the bone surface. These vents also allow bone formation within the anchor channels.
Medial Anchor Placement Following bone bed preparation, an anteromedial bone socket is prepared adjacent to the articular margin for a SwiveLock-C anchor. Using a spinal needle as a guide, a punch is inserted into the anteromedial aspect of the footprint just lateral to the articular margin through a separate percutaneous incision. A SwiveLock-C anchor is preloaded with FiberTape suture and is placed through the same percutaneous portal used for punch insertion. The eyelet is seated until the anchor contacts the bone and then the anchor is screwed into the bone socket. The insertion sheath is backed off to confirm that the top of the anchor is seated at or just below the bone surface. A posteromedial anchor is then inserted in the same fashion.
Restore Normal Length-Tension Relationships As mentioned previously, it is important to restore the normal length-tension relationship of the tendon. The location of medial suture placement is critical as the position of these passes determines the medial to lateral tension and anterior to posterior position. For instance, if the sutures are placed too far laterally in the tendon, the tendon would be undertensioned and the lateral tendon edge would not cover the footprint. Conversely, placing sutures too far medially in the tendon would result in overtension of the repair. We believe that such medial placement is in large part responsible for the reports of medial tendon failure following double-row repair. While viewing from a posterior portal, a grasper is introduced from an anterior portal and used to temporarily reduce the tendon so that the surgeon can visualize the ideal location for placement of the medial sutures. The ideal anatomical position of suture placement would be 2-3 mm lateral to the musculotendinous junction; visualization of this junction is yet another reason why complete bursectomy is valuable before repair. Neyton et al26 recently reported that when the musculotendinous junction was visualized and the medial sutures of a suture-bridging repair were placed lateral to the musculotendinous junction, the incidence of medial tendon failure was only 1 in 107 cases. Once this medial to lateral location for suture placement is determined, the anterior to posterior suture placement would simply be matched to the corresponding anchor location. In the SpeedBridge repair, sutures from a medial anchor are passed through the rotator cuff all at once. If no medial knots
Arthroscopic rotator cuff repair are to be tied, the FiberTape sutures can simply be retrieved and passed through the rotator cuff with an antegrade suture passer (Scorpion; Arthrex, Inc). A FiberTape suture tapers to the diameter of a number 2 FiberWire. That allows the FiberTape to be passed through the rotator cuff with a standard
87 antegrade passer. In the SutureBridge kit, the 2 ends of the FiberWire are bonded together so that both FiberTape suture limbs can be passed through the rotator cuff with a single pass. However, in most cases, we prefer to also pass the eyelet safety sutures through the same location so that a medial doublepulley repair can also be performed to seal off the medial border of the footprint. This is accomplished with the use of a FiberLink suture that is used to shuttle the FiberTape and the FiberWire eyelet sutures through the rotator cuff. FiberLink is a number 2 FiberWire suture that has a closed loop on one end. The free end of the FiberLink suture is loaded onto a Scorpion (Arthrex, Inc), inserted through a lateral working portal, and passed through the rotator cuff as previously described. The free end of the FiberLink is retrieved out an anterior portal, while the looped end is held outside the lateral portal. The FiberTape and FiberWire sutures from the anteromedial anchor are then retrieved out of the lateral portal and threaded through the looped end of the FiberLink. Finally, by pulling the free end the FiberLink, these sutures are shuttled through the rotator cuff at a single point. This step is repeated for the sutures from the posteromedial anchor. To shuttle the sutures from the posteromedial anchor, we often retrieve the free end of the FiberLink out of the same percutaneous portal used for anchor placement so that there would be a less acute angle of pull and less chance of the sutures cutting the tendons they are being shuttled through. In most cases, before obtaining lateral fixation, we prefer to tie medial mattress stitches with a double-pulley technique using the number 2 FiberWire safety eyelet sutures from the SwiveLock anchors. This medial mattress stitch provides a medial seal between the glenohumeral joint and the rotator cuff and provides independent medial row fixation. In performing this double-pulley repair, a FiberWire suture limb is retrieved from both the anteromedial anchor and posteromedial anchor. Extracorporeally, a 6-throw surgeon’s knot is tied over an instrument. The knot security is checked by pulling on the sutures beneath the knot to ensure that the knot does not slide. The suture limbs are then cut above the knot. The knot is delivered into the subacromial space and seated onto the Figure 3 Schematic of a SpeedBridge (Arthrex, Inc, Naples, FL) rotator cuff repair with medial double-pulley and dog-ear–reduction. (A) Two medial anchors are placed for a SpeedBridge repair. (B) Medial sutures are passed through the rotator cuff in a single pass using a FiberLink (Arthrex, Inc, Naples, FL). Then a mattress stitch is tied between the 2 anchors using the number 2 FiberWire eyelet safety stitches with a double-pulley technique. The FiberLink can then be used for dog-ear reduction. The closed end of the FiberLink is passed through the rotator cuff at the margin of the tear and is retrieved out of the same portal as used for insertion. Inset: Extracorporeally, the closed end of the FiberLink is passed through the looped end to create a cinch loop. (C) The cinch loop, a suture from the anteromedial anchor, and a suture from the posteromedial anchor are secured laterally with a BioComposite SwiveLock C anchor. (D) Final appearance after placement of a posterior FiberLink and a posterolateral anchor. Reproduced with permission from Burkhart SS, Lo IK, Brady PC, et al: The Cowboy’s Companion: A Trail Guide for the Arthroscopic Shoulder Surgeon. Philadelphia, Lippincott, Williams, & Wilkins, 2012. (Color version of figure is available online.)
88 rotator cuff by pulling on the opposite ends of the sutures. Then, the opposite ends of the suture limbs are retrieved and the double mattress stitch is completed by tying a static knot in the subacromial space with a surgeon’s 6th Finger Knot Pusher (Arthrex, Inc). It is important to understand that the second knot must be tied as a static knot. Knot security and loop security are optimized by tying a 6-throw surgeon’s knot in which the fourth and sixth throws are flipped (optimizing knot security) and by tying the knot with a surgeon’s 6th Finger Knot Pusher to optimize loop security.27
P.J. Denard and S.S. Burkhart portal. While maintaining tension on the suture limbs, the lateral cannula is used to determine the appropriate position for an anterolateral anchor. Abduction of the arm would facilitate visualization laterally and rotation of the arm is used to achieve the desired position of insertion that restores the anatomy. It is sometimes necessary to reclear the lateral gutter of soft tissue so as to optimize visualization before retrieving the sutures. A 701 arthroscope is also frequently valuable to see
Reinforce the Rotator Cable A critical biomechanical aspect to rotator cuff repair that is too often overlooked is the importance of a secure repair of both ends of the rotator cable. In 1993, the senior author (S.S.B.) described the cable-crescent complex of the rotator cuff.28 The majority of rotator cuff tears begin within the rotator crescent. As long as the rotator cable attachments are intact, the cuff muscles can produce a distributed load along the cable that is transferred to the bone at the cable attachments. In this way, a torn rotator cuff can still function by load transmission of a distributed load through a construct that is analogous to a suspension bridge. The rotator cable attachments are so important to overhead function and to force transmission that we believe it is important to reinforce their repair during ARCR. The posterior cable attachment corresponds to the attachment of the lower infraspinatus. The anterior cable attachment bifurcates around the top of the bicipital groove, with one part of the anterior cable attachment corresponding to the anterior attachment of the supraspinatus and the other part corresponding to the upper attachment of the subscapularis. Interestingly, a standard suture-bridging repair (2 medial anchors and 2 lateral anchors) of a tear involving the supraspinatus and infraspinatus would frequently leave “dog-ears” at the anterior and posterior margins of the repair. Placing cinch-loop sutures at the anterior and posterior margins to reinforce the repair at the anterior and posterior cable attachments would also eliminate the dog-ears. Once the medial sutures have been placed, the anterior and posterior margins of the tear are assessed for the potential for dog-ears following lateral row fixation. If this is anticipated, FiberLink sutures can be used to create cinch-loops at the apex of each dog-ear. To place a cinch loop, the free end of the suture is loaded onto a Scorpion and passed through the rotator cuff. Then, the free end is retrieved and threaded through the looped end of the suture. Tensioning the free end delivers the loop down to the rotator cuff, creating a cinch-loop stitch.
Linked Lateral Fixation To complete the repair, the FiberTape limbs are crisscrossed and secured laterally with 2 additional SwiveLock anchors. A FiberTape suture limb from the anteromedial anchor, a FiberTape suture limb from the posteromedial anchor, and the anterior dog-ear–reduction suture are retrieved out of a lateral
Figure 4 Left shoulder demonstrating final appearance of a rotator cuff repair using a SpeedBridge (Arthrex, Inc, Naples, FL) technique. (A) Posterior subacromial viewing portal demonstrates the doublerow repair with FiberTape sutures that crisscross the rotator cuff to provide footprint compression. Cinch-loop sutures (blue arrows) are also seen which have been used anteriorly and posteriorly to prevent dog-ears. (B) A close up demonstrates a medial mattress stitch (black arrow) that was tied using a double-pulley technique to seal the medial repair. (C) Intraarticular view from a posterior portal demonstrates restoration of the medial rotator cuff footprint. H, humerus; RC, rotator cuff. Reproduced with permission from Burkhart SS, Lo IK, Brady PC, et al: The Cowboy’s Companion: A Trail Guide for the Arthroscopic Shoulder Surgeon. Philadelphia, Lippincott, Williams, & Wilkins, 2012.
Arthroscopic rotator cuff repair over the lateral edge of the greater tuberosity. A punch is inserted to create a bone socket. Extracorporeally, the FiberTape sutures are fed through the eyelet of the SwiveLock C anchor. The surgeon maintains visualization and holds the anchor, while an assistant holds the cannula firmly in place and removes the punch. This ensures that the position of the bone socket is kept in sight and it allows the anchor to be directly inserted into the bone socket. The anchor is then inserted and the sutures are appropriately tensioned to remove slack from the construct and reduce the tendon to the bone socket. The eyelet of the anchor is seated into the bone socket and advanced until the leading thread of the anchor just contacts the bone socket. While holding the thumb pad on the SwiveLock driver, the anchor is inserted into the bone. The 2 remaining FiberTape suture limbs and the posterior dog-ear– reduction suture are retrieved and the steps are repeated with a posterolateral anchor. The final repair is observed subacromially and intraarticularly. This repair is not only a low-profile transosseous equivalent repair, but it also provides a medial seal from the joint owing to the medial double mattress stitch (Fig. 4).
Postoperative Care Postoperatively, patients are maintained in a sling for 6 weeks. During that time, they are allowed to do active wrist and elbow flexion and extension. Passive external rotation is permitted based on the presence of any associated subscapularis tendon tear. Table slides are initiated immediately after repair of singletendon tears. At 6 weeks, the sling is removed, external rotation is initiated, if not already done, and overhead passive forward flexion begins with a rope and pulley. At 12 weeks postoperation, strengthening and internal rotation are allowed. Strengthening is delayed until 12 weeks postoperation because of the evidence that tendon healing takes approximately 12 weeks and the majority of retears occur within this early postoperative period.14,29,30 Additionally, in our opinion, there is no need to begin aggressive range of motion immediately as the incidence of stiffness after an ARCR is exceeding low.31 Full return to activity including accelerating the arm (tennis, golf, and throwing) are allowed at 6 months postoperation.
Conclusion In the setting of sufficient tendon mobility, double-row suturebridging constructs maximize the restoration of anatomy and biomechanical strength following ARCR. These constructs have substantially improved healing rates and in our opinion should be considered the standard of care for rotator cuff repair.
References 1. Lo IK, Burkhart SS: Double-row arthroscopic rotator cuff repair: Reestablishing the footprint of the rotator cuff. Arthroscopy 19:1035-1042, 2003 2. Brady PC, Arrigoni P, Burkhart SS: Evaluation of residual rotator cuff defects after in vivo single- versus double-row rotator cuff repairs. Arthroscopy 22:1070-1075, 2006
89 3. Ma CB, Comerford L, Wilson J, et al: Biomechanical evaluation of arthroscopic rotator cuff repairs: Double-row compared with single-row fixation. J Bone Joint Surg Am 88:403-410, 2006 4. Meier SW, Meier JD: The effect of double-row fixation on initial repair strength in rotator cuff repair: A biomechanical study. Arthroscopy 22:1168-1173, 2006 5. Park MC, ElAttrache NS, Tibone JE, et al: Footprint contact characteristics for a transosseous-equivalent rotator cuff repair technique compared with a double-row repair technique. J Shoulder Elbow Surg 16:461-468, 2007 6. Park MC, Tibone JE, ElAttrache NS, et al: Biomechanical assessment for a footprint-restoring transosseous-equivalent rotator cuff repair technique compared with a double-row repair technique. J Shoulder Elbow Surg 16:469-476, 2007 7. Burkhart SS, Adams CR, Schoolfield JD: A biomechanical comparison of 2 techniques of footprint reconstruction for rotator cuff repair: The SwiveLock-FiberChain construct versus standard double-row repair. Arthroscopy 25:274-281, 2009 8. Burkhart SS, Cole BJ: Bridging self-reinforcing double-row rotator cuff repair: We really are doing better. Arthroscopy 26:677-680, 2010 9. Burks RT, Crim J, Brown N, et al: A prospective randomized clinical trial comparing arthroscopic single- and double-row rotator cuff repair: Magnetic resonance imaging and early clinical evaluation. Am J Sports Med 37:674-682, 2009 10. Grasso A, Milano G, Salvatore M, et al: Single-row versus double-row arthroscopic rotator cuff repair: A prospective randomized clinical study. Arthroscopy 25:4-12, 2009 11. Franceschi F, Ruzzini L, Longo UG, et al: Equivalent clinical results of arthroscopic single-row and double-row suture anchor repair for rotator cuff tears: A randomized controlled trial. Am J Sports Med 35:1254-1260, 2007 12. Duquin TR, Buyea C, Bisson LJ: Which method of rotator cuff repair leads to the highest rate of structural healing? A systematic review. Am J Sports Med 38:835-841, 2010 13. Harryman DT 2nd, Mack LA, Wang KY, et al: Repairs of the rotator cuff. Correlation of functional results with integrity of the cuff. J Bone Joint Surg Am 73:982-989, 1991 14. Kluger R, Bock P, Mittlbock M, et al: Long-term survivorship of rotator cuff repairs using ultrasound and magnetic resonance imaging analysis. Am J Sports Med 39:2071-2081, 2011 15. Denard PJ, Jiwani AZ, Ladermann A, et al: Long-term outcome of arthroscopic massive rotator cuff repair: The importance of double-row fixation. Arthroscopy 28:909-915, 2012 16. Frank JB, ElAttrache NS, Dines JS, et al: Repair site integrity after arthroscopic transosseous-equivalent suture-bridge rotator cuff repair. Am J Sports Med 36:1496-1503, 2008 17. Toussaint B, Schnaser E, Bosley J, et al: Early structural and functional outcomes for arthroscopic double-row transosseous-equivalent rotator cuff repair. Am J Sports Med 39:1217-1225, 2011 18. Kim KC, Shin HD, Lee WY: Repair integrity and functional outcomes after arthroscopic suture-bridge rotator cuff repair. J Bone Joint Surg Am 94: e48, 2012 19. Mihata T, Watanabe C, Fukunishi K, et al: Functional and structural outcomes of single-row versus double-row versus combined double-row and suture-bridge repair for rotator cuff tears. Am J Sports Med 39:2091-2098, 2011 20. Sethi PM, Noonan BC, Cunningham J, et al: Repair results of 2-tendon rotator cuff tears utilizing the transosseous equivalent technique. J Shoulder Elbow Surg 19:1210-1217, 2010 21. Park JY, Siti HT, Keum JS, et al: Does an arthroscopic suture bridge technique maintain repair integrity? A serial evaluation by ultrasonography. Clin Orthop Relat Res 468:1578-1587, 2010 22. Arrigoni P, Brady PC, Burkhart SS: The double-pulley technique for double-row rotator cuff repair. Arthroscopy 23:e1-e4, 2007 23. Kaplan K, ElAttrache NS, Vazquez O, et al: Knotless rotator cuff repair in an external rotation model: The importance of medial-row horizontal mattress sutures. Arthroscopy 27:471-478, 2011
90 24. Gamradt SC, Gallo RA, Adler RS, et al: Vascularity of the supraspinatus tendon three months after repair: Characterization using contrastenhanced ultrasound. J Shoulder Elbow Surg 19:73-80, 2010 25. Christoforetti JJ, Krupp RJ, Singleton SB, et al: Arthroscopic suture bridge transosseus equivalent fixation of rotator cuff tendon preserves intratendinous blood flow at the time of initial fixation. J Shoulder Elbow Surg 21:523-530, 2012 26. Neyton L, Godeneche A, Nove-Josserand L, et al: Arthroscopic suturebridge repair for small to medium size supraspinatus tear: Healing rate and retear pattern. Arthroscopy 29:10-17, 2013 27. Lo IK, Burkhart SS, Chan KC, et al: Arthroscopic knots: Determining the optimal balance of loop security and knot security. Arthroscopy 20:489-502, 2004
P.J. Denard and S.S. Burkhart 28. Burkhart SS, Esch JC, Jolson RS: The rotator crescent and rotator cable: An anatomic description of the shoulder’s “suspension bridge”. Arthroscopy 9:611-616, 1993 29. Sonnabend DH, Howlett CR, Young AA: Histological evaluation of repair of the rotator cuff in a primate model. J Bone Joint Surg Br 92:586-594, 2010 30. Miller BS, Downie BK, Kohen RB, et al: When do rotator cuff repairs fail? Serial ultrasound examination after arthroscopic repair of large and massive rotator cuff tears. Am J Sports Med 39:2064-2070, 2011 31. Denard PJ, Ladermann A, Burkhart SS: Prevention and management of stiffness following arthroscopic rotator cuff repair: Systematic review and implications for rotator cuff healing. Arthroscopy 27:842-848, 2011
R
otator cuff repair has undergone dramatic advancements over the past 2 decades, progressing from extensile open repairs to arthroscopic repairs that can be performed in a minimally invasive fashion while maximizing restoration of the anatomy. Initially, arthroscopic rotator cuff repair (ARCR) was performed with a single row of medial anchors. Doublerow repairs evolved as surgeons attempted to achieve more anatomical rotator cuff repairs. In an effort to improve footprint restoration and biomechanical strength, repairs have transitioned from a nonlinked double-row repair to a suture-bridging double-row repair. This review highlights our rationale for suture-bridging double-row ARCR and describes our current technique for repair of a standard medium-sized crescent-shaped tear.
Rationale for Double-Row Repair Biomechanically, the goal of a rotator cuff repair is to achieve high initial fixation strength, minimize gap formation, and maximize contact area. In other words, although biology plays an important role in rotator cuff tendon healing, biomechanical factors must be optimized by the surgeon at time zero to provide the best chance for tendon healing. *
Southern Oregon Orthopedics, Medford, OR. †Department of Orthopaedics and Rehabilitation, Oregon Health & Science University, Portland, OR. ‡The San Antonio Orthopaedic Group, San Antonio, TX. Address reprint requests to Stephen S. Burkhart, MD, 150 E Sonterra Blvd, Suite 300, San Antonio, TX 78259. E-mail: [email protected]
84
1048-6666/13/$-see front matter & 2013 Elsevier Inc. All rights reserved. doi:http://dx.doi.org/10.1053/j.oto.2013.05.005
The traditional double-row repair consisted of independent rows of medial and lateral anchors in which the medial sutures were placed as mattress stitches and the lateral sutures were placed as simple sutures.1 This repair improved footprint restoration,2 and fixation strength as compared with singlerow repairs.3,4 The advancement of knotless suture anchors not only simplified the technical demand of ARCR, but more importantly allowed the creation of suture-bridging constructs whereby the medial and lateral rows are linked (Fig. 1). Suturebridging repairs, which link the 2 rows, have improved pressurized footprint contact area and ultimate load to failure compared with a traditional double-row repair.5,6 Moreover, because the medial and lateral rows of the suture-bridging double-row repair are linked, the construct exhibits selfreinforcing properties much like a Chinese finger trap (Fig. 2).7 Although there has been some debate in the literature about clinical outcomes after single-row repair vs double-row repair, several key factors should be considered, and they have been briefly discussed here. For a more extensive review of this debate, the reader is referred elsewhere.8 The initial studies reported on short-term functional outcome of single-row repairs compared with a traditional nonlinked double-row repair.9-11 With patient cohorts between 40 and 80 patients, these studies were underpowered to detect differences between the 2 groups. Meta-analysis, however, has revealed that healing rates are improved with double-row repairs. Duquin et al12 reviewed 23 articles with a total of 1252 rotator cuff repairs. In their pooled analysis, the recurrence rate for tears ≤3 cm was 19% following single-row repair compared with only 7% following double-row repair. For tears larger than 3 cm, the
Arthroscopic rotator cuff repair
85
Figure 1 Comparison of traditional double-row repair and suture-bridging double-row repair. (A) With the original doublerow rotator cuff repair, 2 medial anchors were placed, sutures were individually passed and tied as mattress stitches, and then the suture limbs were cut. Two lateral anchors were also placed, sutures were passed and tied as simple stitches, and the suture limbs were cut. (B) In a suture-bridging double-row repair, the medial and lateral rows are linked. Two medial suture anchors are placed and sutures from these anchors are individually passed and tied as mattress stitches. Rather than cutting the suture limbs however, the sutures are crisscrossed and secured laterally to 2 knotless anchors. This repair mechanically links the 2 rows and provides enhanced footprint compression to encourage rotator cuff healing. Reproduced with permission from Burkhart SS, Lo IK, Brady PC, et al: The Cowboy’s Companion: A Trail Guide for the Arthroscopic Shoulder Surgeon. Philadelphia, Lippincott, Williams, & Wilkins, 2012. (Color version of figure is available online.)
retear rate increased to 45% following single-row repair vs 26% following double-row repair. These improved healing rates are important given that13,14 healing is associated with a superior functional outcome at midterm and long-term follow-up. Moreover, as opposed to the short-term follow-up (1-2 years) of the aforementioned studies, long-term follow-up has demonstrated that functional outcome is also superior following a
double-row repair compared with a single-row repair. Denard et al,15 for instance, demonstrated that a traditional double-row repair of a massive tear was 4.9 times more likely to lead to a good or excellent functional outcome compared with a singlerow repair at a mean of 99 months postoperatively. Excellent outcomes of suture-bridging double-row repairs have also recently been reported in several clinical studies.
Figure 2 Schematic of self-reinforcing suture-bridge technique. (A) Linked double-row construct before loading. Inset: Freebody diagram of the construct. H1, thickness of rotator cuff before loading; L1, length of tendon beneath suture. (B) Loading of the linked double-row construct results in compression of the rotator cuff footprint. Inset: Free-body diagram of the construct. T, tensile loading force; L2, length of tendon beneath suture; a, length of suture between tendon edge and lateral anchor; H2, thickness of compressed rotator cuff under tensile load. (C) Up close view of the linked double-row construct after loading. Inset: Free-body diagram showing distributed normal force (N) resulting from elastic deformation of tendon beneath the suture. The frictional force (f) increases as the normal force (N) increases under load. (D) Linked double-row construct with 2 medial anchors linked to 2 lateral anchors provides maximal footprint compression under loading. Additionally, a medial double mattress stitch in this case provides a seal to joint fluid. Reproduced with permission from Burkhart SS, Lo IK, Brady PC, et al: The Cowboy’s Companion: A Trail Guide for the Arthroscopic Shoulder Surgeon. Philadelphia, Lippincott, Williams, & Wilkins, 2012. (Color version of figure is available online.)
P.J. Denard and S.S. Burkhart
86 Frank et al16 reported an 88% rate of healing in 25 rotator cuff tears repaired with a suture-bridging construct. Toussaint et al17 reported on 154 repairs and observed a 92% rate of healing in small tears as well as an impressive 84% rate of healing among massive tears. Other studies have demonstrated similarly high rates of healing.18-21 Based on these improved healing rates, in our opinion, a suture-bridging double-row repair is the current standard of care for rotator cuff repair.
Surgical Technique In the setting of sufficient tendon mobility, we always perform a suture-bridging repair of medium-sized crescent tears. However, if there is insufficient tendon mobility or tendon loss such that pulling the tendon to the lateral part of the tuberosity would result in overtension of the repair, we do not do a footprint reconstruction. Tissue quality also influences the types of suture-bridging repairs that we perform. For goodquality tissue, we use a knotless SpeedBridge technique with FiberTape and 2 rows of BioComposite SwiveLock-C suture anchors (Arthrex, Inc, Naples, FL). For fair-quality tissue, we utilize a SpeedBridge repair augmented with a medial double mattress suture (double-pulley technique22) as medial mattress sutures enhance the fixation of a knotless repair.23 If the tissue quality is poor, we use more suture passes through the tendon and more knots to strengthen the construct (SutureBridge; Arthrex, Inc). In addition, in keeping with our opinion that the anatomy should be restored as closely as possible, we make every effort to restore the natural rotator cable insertions by placing independent sutures to reinforce the rotator cable attachments at the anterior and posterior margins of the repair. These independent cinch-loop sutures also serve to reduce the dog-ears that typically appear at the anterior and posterior margins of the footprint repair. In the following section, we describe our technique for a SpeedBridge repair (Fig. 3). However, the steps for a SutureBridge repair are essentially the same, with the exception that more suture passes are performed medially and all sutures are tied before linking the sutures to the lateral row.
Prepare the Soft Tissues and Bone Bed Following diagnostic arthroscopy, the soft tissues and bone bed are prepared for repair. A complete bursectomy is performed, allowing the surgeon to see the entire margin of the cuff tear. This is essential, because you must clearly see the tendon so as to accurately repair it. Secondly, it removes the potentially harmful degradative enzymes that reside in the subacromial bursa. In addition to the bursectomy, the surgeon must debride any bursal leaders that attach to the internal deltoid fascia, and he must debride friable tendon edges while retaining robust tendon even if it appears poorly vascularized. Bone bed preparation is critically important to achieving tendon-to-bone healing. Soft tissue is removed from the greater tuberosity with an electrocautery (which creates a charcoallike film on the bone surface) and then a high-speed burr is applied to lightly “burr off the charcoal.” It has been shown that the
greatest blood supply for rotator cuff healing comes from the bone.24 Furthermore, although some have raised the concern that compression from a suture-bridging repair would decrease blood flow to the tendon, it has been shown that blood flow to the tendon is preserved with this type of repair.25 To enhance the amount of blood and bone marrow products that reach the tendon-bone interface, we also prefer to use vented suture anchors that have side vents in addition to the longitudinal cannulation through which blood products from the bone marrow can reach the repair interface at the bone surface. These vents also allow bone formation within the anchor channels.
Medial Anchor Placement Following bone bed preparation, an anteromedial bone socket is prepared adjacent to the articular margin for a SwiveLock-C anchor. Using a spinal needle as a guide, a punch is inserted into the anteromedial aspect of the footprint just lateral to the articular margin through a separate percutaneous incision. A SwiveLock-C anchor is preloaded with FiberTape suture and is placed through the same percutaneous portal used for punch insertion. The eyelet is seated until the anchor contacts the bone and then the anchor is screwed into the bone socket. The insertion sheath is backed off to confirm that the top of the anchor is seated at or just below the bone surface. A posteromedial anchor is then inserted in the same fashion.
Restore Normal Length-Tension Relationships As mentioned previously, it is important to restore the normal length-tension relationship of the tendon. The location of medial suture placement is critical as the position of these passes determines the medial to lateral tension and anterior to posterior position. For instance, if the sutures are placed too far laterally in the tendon, the tendon would be undertensioned and the lateral tendon edge would not cover the footprint. Conversely, placing sutures too far medially in the tendon would result in overtension of the repair. We believe that such medial placement is in large part responsible for the reports of medial tendon failure following double-row repair. While viewing from a posterior portal, a grasper is introduced from an anterior portal and used to temporarily reduce the tendon so that the surgeon can visualize the ideal location for placement of the medial sutures. The ideal anatomical position of suture placement would be 2-3 mm lateral to the musculotendinous junction; visualization of this junction is yet another reason why complete bursectomy is valuable before repair. Neyton et al26 recently reported that when the musculotendinous junction was visualized and the medial sutures of a suture-bridging repair were placed lateral to the musculotendinous junction, the incidence of medial tendon failure was only 1 in 107 cases. Once this medial to lateral location for suture placement is determined, the anterior to posterior suture placement would simply be matched to the corresponding anchor location. In the SpeedBridge repair, sutures from a medial anchor are passed through the rotator cuff all at once. If no medial knots
Arthroscopic rotator cuff repair are to be tied, the FiberTape sutures can simply be retrieved and passed through the rotator cuff with an antegrade suture passer (Scorpion; Arthrex, Inc). A FiberTape suture tapers to the diameter of a number 2 FiberWire. That allows the FiberTape to be passed through the rotator cuff with a standard
87 antegrade passer. In the SutureBridge kit, the 2 ends of the FiberWire are bonded together so that both FiberTape suture limbs can be passed through the rotator cuff with a single pass. However, in most cases, we prefer to also pass the eyelet safety sutures through the same location so that a medial doublepulley repair can also be performed to seal off the medial border of the footprint. This is accomplished with the use of a FiberLink suture that is used to shuttle the FiberTape and the FiberWire eyelet sutures through the rotator cuff. FiberLink is a number 2 FiberWire suture that has a closed loop on one end. The free end of the FiberLink suture is loaded onto a Scorpion (Arthrex, Inc), inserted through a lateral working portal, and passed through the rotator cuff as previously described. The free end of the FiberLink is retrieved out an anterior portal, while the looped end is held outside the lateral portal. The FiberTape and FiberWire sutures from the anteromedial anchor are then retrieved out of the lateral portal and threaded through the looped end of the FiberLink. Finally, by pulling the free end the FiberLink, these sutures are shuttled through the rotator cuff at a single point. This step is repeated for the sutures from the posteromedial anchor. To shuttle the sutures from the posteromedial anchor, we often retrieve the free end of the FiberLink out of the same percutaneous portal used for anchor placement so that there would be a less acute angle of pull and less chance of the sutures cutting the tendons they are being shuttled through. In most cases, before obtaining lateral fixation, we prefer to tie medial mattress stitches with a double-pulley technique using the number 2 FiberWire safety eyelet sutures from the SwiveLock anchors. This medial mattress stitch provides a medial seal between the glenohumeral joint and the rotator cuff and provides independent medial row fixation. In performing this double-pulley repair, a FiberWire suture limb is retrieved from both the anteromedial anchor and posteromedial anchor. Extracorporeally, a 6-throw surgeon’s knot is tied over an instrument. The knot security is checked by pulling on the sutures beneath the knot to ensure that the knot does not slide. The suture limbs are then cut above the knot. The knot is delivered into the subacromial space and seated onto the Figure 3 Schematic of a SpeedBridge (Arthrex, Inc, Naples, FL) rotator cuff repair with medial double-pulley and dog-ear–reduction. (A) Two medial anchors are placed for a SpeedBridge repair. (B) Medial sutures are passed through the rotator cuff in a single pass using a FiberLink (Arthrex, Inc, Naples, FL). Then a mattress stitch is tied between the 2 anchors using the number 2 FiberWire eyelet safety stitches with a double-pulley technique. The FiberLink can then be used for dog-ear reduction. The closed end of the FiberLink is passed through the rotator cuff at the margin of the tear and is retrieved out of the same portal as used for insertion. Inset: Extracorporeally, the closed end of the FiberLink is passed through the looped end to create a cinch loop. (C) The cinch loop, a suture from the anteromedial anchor, and a suture from the posteromedial anchor are secured laterally with a BioComposite SwiveLock C anchor. (D) Final appearance after placement of a posterior FiberLink and a posterolateral anchor. Reproduced with permission from Burkhart SS, Lo IK, Brady PC, et al: The Cowboy’s Companion: A Trail Guide for the Arthroscopic Shoulder Surgeon. Philadelphia, Lippincott, Williams, & Wilkins, 2012. (Color version of figure is available online.)
88 rotator cuff by pulling on the opposite ends of the sutures. Then, the opposite ends of the suture limbs are retrieved and the double mattress stitch is completed by tying a static knot in the subacromial space with a surgeon’s 6th Finger Knot Pusher (Arthrex, Inc). It is important to understand that the second knot must be tied as a static knot. Knot security and loop security are optimized by tying a 6-throw surgeon’s knot in which the fourth and sixth throws are flipped (optimizing knot security) and by tying the knot with a surgeon’s 6th Finger Knot Pusher to optimize loop security.27
P.J. Denard and S.S. Burkhart portal. While maintaining tension on the suture limbs, the lateral cannula is used to determine the appropriate position for an anterolateral anchor. Abduction of the arm would facilitate visualization laterally and rotation of the arm is used to achieve the desired position of insertion that restores the anatomy. It is sometimes necessary to reclear the lateral gutter of soft tissue so as to optimize visualization before retrieving the sutures. A 701 arthroscope is also frequently valuable to see
Reinforce the Rotator Cable A critical biomechanical aspect to rotator cuff repair that is too often overlooked is the importance of a secure repair of both ends of the rotator cable. In 1993, the senior author (S.S.B.) described the cable-crescent complex of the rotator cuff.28 The majority of rotator cuff tears begin within the rotator crescent. As long as the rotator cable attachments are intact, the cuff muscles can produce a distributed load along the cable that is transferred to the bone at the cable attachments. In this way, a torn rotator cuff can still function by load transmission of a distributed load through a construct that is analogous to a suspension bridge. The rotator cable attachments are so important to overhead function and to force transmission that we believe it is important to reinforce their repair during ARCR. The posterior cable attachment corresponds to the attachment of the lower infraspinatus. The anterior cable attachment bifurcates around the top of the bicipital groove, with one part of the anterior cable attachment corresponding to the anterior attachment of the supraspinatus and the other part corresponding to the upper attachment of the subscapularis. Interestingly, a standard suture-bridging repair (2 medial anchors and 2 lateral anchors) of a tear involving the supraspinatus and infraspinatus would frequently leave “dog-ears” at the anterior and posterior margins of the repair. Placing cinch-loop sutures at the anterior and posterior margins to reinforce the repair at the anterior and posterior cable attachments would also eliminate the dog-ears. Once the medial sutures have been placed, the anterior and posterior margins of the tear are assessed for the potential for dog-ears following lateral row fixation. If this is anticipated, FiberLink sutures can be used to create cinch-loops at the apex of each dog-ear. To place a cinch loop, the free end of the suture is loaded onto a Scorpion and passed through the rotator cuff. Then, the free end is retrieved and threaded through the looped end of the suture. Tensioning the free end delivers the loop down to the rotator cuff, creating a cinch-loop stitch.
Linked Lateral Fixation To complete the repair, the FiberTape limbs are crisscrossed and secured laterally with 2 additional SwiveLock anchors. A FiberTape suture limb from the anteromedial anchor, a FiberTape suture limb from the posteromedial anchor, and the anterior dog-ear–reduction suture are retrieved out of a lateral
Figure 4 Left shoulder demonstrating final appearance of a rotator cuff repair using a SpeedBridge (Arthrex, Inc, Naples, FL) technique. (A) Posterior subacromial viewing portal demonstrates the doublerow repair with FiberTape sutures that crisscross the rotator cuff to provide footprint compression. Cinch-loop sutures (blue arrows) are also seen which have been used anteriorly and posteriorly to prevent dog-ears. (B) A close up demonstrates a medial mattress stitch (black arrow) that was tied using a double-pulley technique to seal the medial repair. (C) Intraarticular view from a posterior portal demonstrates restoration of the medial rotator cuff footprint. H, humerus; RC, rotator cuff. Reproduced with permission from Burkhart SS, Lo IK, Brady PC, et al: The Cowboy’s Companion: A Trail Guide for the Arthroscopic Shoulder Surgeon. Philadelphia, Lippincott, Williams, & Wilkins, 2012.
Arthroscopic rotator cuff repair over the lateral edge of the greater tuberosity. A punch is inserted to create a bone socket. Extracorporeally, the FiberTape sutures are fed through the eyelet of the SwiveLock C anchor. The surgeon maintains visualization and holds the anchor, while an assistant holds the cannula firmly in place and removes the punch. This ensures that the position of the bone socket is kept in sight and it allows the anchor to be directly inserted into the bone socket. The anchor is then inserted and the sutures are appropriately tensioned to remove slack from the construct and reduce the tendon to the bone socket. The eyelet of the anchor is seated into the bone socket and advanced until the leading thread of the anchor just contacts the bone socket. While holding the thumb pad on the SwiveLock driver, the anchor is inserted into the bone. The 2 remaining FiberTape suture limbs and the posterior dog-ear– reduction suture are retrieved and the steps are repeated with a posterolateral anchor. The final repair is observed subacromially and intraarticularly. This repair is not only a low-profile transosseous equivalent repair, but it also provides a medial seal from the joint owing to the medial double mattress stitch (Fig. 4).
Postoperative Care Postoperatively, patients are maintained in a sling for 6 weeks. During that time, they are allowed to do active wrist and elbow flexion and extension. Passive external rotation is permitted based on the presence of any associated subscapularis tendon tear. Table slides are initiated immediately after repair of singletendon tears. At 6 weeks, the sling is removed, external rotation is initiated, if not already done, and overhead passive forward flexion begins with a rope and pulley. At 12 weeks postoperation, strengthening and internal rotation are allowed. Strengthening is delayed until 12 weeks postoperation because of the evidence that tendon healing takes approximately 12 weeks and the majority of retears occur within this early postoperative period.14,29,30 Additionally, in our opinion, there is no need to begin aggressive range of motion immediately as the incidence of stiffness after an ARCR is exceeding low.31 Full return to activity including accelerating the arm (tennis, golf, and throwing) are allowed at 6 months postoperation.
Conclusion In the setting of sufficient tendon mobility, double-row suturebridging constructs maximize the restoration of anatomy and biomechanical strength following ARCR. These constructs have substantially improved healing rates and in our opinion should be considered the standard of care for rotator cuff repair.
References 1. Lo IK, Burkhart SS: Double-row arthroscopic rotator cuff repair: Reestablishing the footprint of the rotator cuff. Arthroscopy 19:1035-1042, 2003 2. Brady PC, Arrigoni P, Burkhart SS: Evaluation of residual rotator cuff defects after in vivo single- versus double-row rotator cuff repairs. Arthroscopy 22:1070-1075, 2006
89 3. Ma CB, Comerford L, Wilson J, et al: Biomechanical evaluation of arthroscopic rotator cuff repairs: Double-row compared with single-row fixation. J Bone Joint Surg Am 88:403-410, 2006 4. Meier SW, Meier JD: The effect of double-row fixation on initial repair strength in rotator cuff repair: A biomechanical study. Arthroscopy 22:1168-1173, 2006 5. Park MC, ElAttrache NS, Tibone JE, et al: Footprint contact characteristics for a transosseous-equivalent rotator cuff repair technique compared with a double-row repair technique. J Shoulder Elbow Surg 16:461-468, 2007 6. Park MC, Tibone JE, ElAttrache NS, et al: Biomechanical assessment for a footprint-restoring transosseous-equivalent rotator cuff repair technique compared with a double-row repair technique. J Shoulder Elbow Surg 16:469-476, 2007 7. Burkhart SS, Adams CR, Schoolfield JD: A biomechanical comparison of 2 techniques of footprint reconstruction for rotator cuff repair: The SwiveLock-FiberChain construct versus standard double-row repair. Arthroscopy 25:274-281, 2009 8. Burkhart SS, Cole BJ: Bridging self-reinforcing double-row rotator cuff repair: We really are doing better. Arthroscopy 26:677-680, 2010 9. Burks RT, Crim J, Brown N, et al: A prospective randomized clinical trial comparing arthroscopic single- and double-row rotator cuff repair: Magnetic resonance imaging and early clinical evaluation. Am J Sports Med 37:674-682, 2009 10. Grasso A, Milano G, Salvatore M, et al: Single-row versus double-row arthroscopic rotator cuff repair: A prospective randomized clinical study. Arthroscopy 25:4-12, 2009 11. Franceschi F, Ruzzini L, Longo UG, et al: Equivalent clinical results of arthroscopic single-row and double-row suture anchor repair for rotator cuff tears: A randomized controlled trial. Am J Sports Med 35:1254-1260, 2007 12. Duquin TR, Buyea C, Bisson LJ: Which method of rotator cuff repair leads to the highest rate of structural healing? A systematic review. Am J Sports Med 38:835-841, 2010 13. Harryman DT 2nd, Mack LA, Wang KY, et al: Repairs of the rotator cuff. Correlation of functional results with integrity of the cuff. J Bone Joint Surg Am 73:982-989, 1991 14. Kluger R, Bock P, Mittlbock M, et al: Long-term survivorship of rotator cuff repairs using ultrasound and magnetic resonance imaging analysis. Am J Sports Med 39:2071-2081, 2011 15. Denard PJ, Jiwani AZ, Ladermann A, et al: Long-term outcome of arthroscopic massive rotator cuff repair: The importance of double-row fixation. Arthroscopy 28:909-915, 2012 16. Frank JB, ElAttrache NS, Dines JS, et al: Repair site integrity after arthroscopic transosseous-equivalent suture-bridge rotator cuff repair. Am J Sports Med 36:1496-1503, 2008 17. Toussaint B, Schnaser E, Bosley J, et al: Early structural and functional outcomes for arthroscopic double-row transosseous-equivalent rotator cuff repair. Am J Sports Med 39:1217-1225, 2011 18. Kim KC, Shin HD, Lee WY: Repair integrity and functional outcomes after arthroscopic suture-bridge rotator cuff repair. J Bone Joint Surg Am 94: e48, 2012 19. Mihata T, Watanabe C, Fukunishi K, et al: Functional and structural outcomes of single-row versus double-row versus combined double-row and suture-bridge repair for rotator cuff tears. Am J Sports Med 39:2091-2098, 2011 20. Sethi PM, Noonan BC, Cunningham J, et al: Repair results of 2-tendon rotator cuff tears utilizing the transosseous equivalent technique. J Shoulder Elbow Surg 19:1210-1217, 2010 21. Park JY, Siti HT, Keum JS, et al: Does an arthroscopic suture bridge technique maintain repair integrity? A serial evaluation by ultrasonography. Clin Orthop Relat Res 468:1578-1587, 2010 22. Arrigoni P, Brady PC, Burkhart SS: The double-pulley technique for double-row rotator cuff repair. Arthroscopy 23:e1-e4, 2007 23. Kaplan K, ElAttrache NS, Vazquez O, et al: Knotless rotator cuff repair in an external rotation model: The importance of medial-row horizontal mattress sutures. Arthroscopy 27:471-478, 2011
90 24. Gamradt SC, Gallo RA, Adler RS, et al: Vascularity of the supraspinatus tendon three months after repair: Characterization using contrastenhanced ultrasound. J Shoulder Elbow Surg 19:73-80, 2010 25. Christoforetti JJ, Krupp RJ, Singleton SB, et al: Arthroscopic suture bridge transosseus equivalent fixation of rotator cuff tendon preserves intratendinous blood flow at the time of initial fixation. J Shoulder Elbow Surg 21:523-530, 2012 26. Neyton L, Godeneche A, Nove-Josserand L, et al: Arthroscopic suturebridge repair for small to medium size supraspinatus tear: Healing rate and retear pattern. Arthroscopy 29:10-17, 2013 27. Lo IK, Burkhart SS, Chan KC, et al: Arthroscopic knots: Determining the optimal balance of loop security and knot security. Arthroscopy 20:489-502, 2004
P.J. Denard and S.S. Burkhart 28. Burkhart SS, Esch JC, Jolson RS: The rotator crescent and rotator cable: An anatomic description of the shoulder’s “suspension bridge”. Arthroscopy 9:611-616, 1993 29. Sonnabend DH, Howlett CR, Young AA: Histological evaluation of repair of the rotator cuff in a primate model. J Bone Joint Surg Br 92:586-594, 2010 30. Miller BS, Downie BK, Kohen RB, et al: When do rotator cuff repairs fail? Serial ultrasound examination after arthroscopic repair of large and massive rotator cuff tears. Am J Sports Med 39:2064-2070, 2011 31. Denard PJ, Ladermann A, Burkhart SS: Prevention and management of stiffness following arthroscopic rotator cuff repair: Systematic review and implications for rotator cuff healing. Arthroscopy 27:842-848, 2011