Rotator cuff repair: the effect of double-row fixation on three-dimensional repair site

Arthroscopic evaluation of the rotator cuff vasculature: inferences into the pathogenesis of cuff tear and re-tear

BACKGROUND

Little is known about alterations of the rotator cuff (RC) macroscopic vasculature associated with medical conditions and/or habits that predispose a person to diseases of the peripheral microcirculation. The high frequency of cuff tear and re-tear in patients with diabetes, hypercholesterolemia, uncontrolled arterial hypertension, or metabolic syndrome may be due to tissue hypovascularity.

METHODS

The macroscopic vasculature of both the articular and bursal sides of the posterosuperior RC was evaluated arthroscopically in 107 patients (mean age, 58.2 years) with no RC tear. Patients were divided into three groups according to medical comorbidities and lifestyle factors (group I, none; group II, smokers and/or drinkers and one comorbidity; and group III, two or more comorbidities). Pulsating vessels originating from both the myotendinous and osteotendinous junctions were assessed as "clearly evident," "poorly evident," or "not evident."

RESULTS

Groups I, II, and III comprised 36, 45, and 26 patients, respectively. Within the myotendinous junction, vessels were visualized in 22 group I patients (61%), 25 group II patients (55%), and 6 group III patients (23%) (P=0.007). Pulsating arterial vessels originating from the osteotendinous junction were seen in 42%, 36%, and 0% of patients, respectively (P<0.001). Within the bursal side of the RC, a dense anastomotic network was visualized (either clearly or poorly) in 94% (34), 80% (36), and 35% (9) of patients, respectively (P<0.001).

CONCLUSIONS

The macroscopic vasculature of the RC is influenced by pre-existing diseases and lifestyle factors, which may impair peripheral microcirculation. Level of evidence: III.

Healthcare costs of failed rotator cuff repairs

Background

The goal of this study was to estimate the short-term (∼2 years) healthcare costs of failed primary arthroscopic rotator cuff repair (RCR) in the United States.

Methods

A review of current literature was performed to estimate the number of RCR performed in the United States in the year 2022 and the rate of progression of these patients to lose repair continuity, reach clinical failure, and progress to nonoperative intervention and revision procedures. A review of the current literature was performed to estimate the costs incurred by these failures over the ensuing 2-year postoperative time period.

Results

The direct and indirect healthcare costs of structural and clinical failure of primary RCR performed in 2022 are estimated to reach $438,892,670 in the short-term postoperative period. The majority of the costs come from the estimated $229,390,898 in nonoperative management that these patients undergo after they reach clinical failure.

Conclusion

The short-term healthcare costs of failed arthroscopic RCR performed in the United States in 2022 are predicted to be $438,892,670. Although RCR improves quality of life, pain, function, and is cost-effective, there remains great potential for reducing the economic burden of failed RCR repairs on the US society. Investments into research aimed to improve RCR healing rates are warranted.

Clinical Relevance

Although RCR improves quality of life, pain, function, and is cost-effective, this study provides evidence that there remains great potential for reducing the economic burden of failed RCR repairs on the US society. Investments into research aimed to improve RCR healing rates are warranted.

Arthroscopic Double-Row Repair of Posterosuperior Rotator Cuff Tears: Suture Bridge Technique Reinforced With Modified Mason-Allen and Simple Sutures

Rotator cuff (RC) tears represent one of the most common causes of pain and dysfunction of the shoulder. Numerous RC repair techniques have been reported. In this Technical Note, we introduce an arthroscopic double-row repair technique that combines a suture bridge construct with modified Mason-Allen and simple suture fixation to optimize load-sharing and compression of the RC to the footprint. The described technique is ideal for crescent-shaped and large reparable U-shaped posterosuperior RC tears.

Superior Capsular Reconstruction With Autologous Fascia Lata Using a Single Lateral-Row Technique Is an Effective Option in Massive Irreparable Rotator Cuff Tears: Minimum 2-Year Follow-Up

PURPOSE

The purpose of this study was to evaluate clinical and radiologic outcomes of arthroscopic superior capsular reconstruction (ASCR) with fascia lata autograft in patients with irreparable rotator cuff tears (IRCTs) performed using a single lateral-row fixation technique.

METHODS

We studied a retrospective case series of patients with large or massive IRCTs for ASCR with fascia lata autograft. Clinical outcomes were evaluated using the Visual Analog Scale (VAS) and the Constant score. Healing of the graft was assessed by magntic resonance imaging or ultrasound. Acromiohumeral distance was evaluated by radiographs.

RESULTS

Thirty-one patients with an average age of 61 years and an average follow-up of 35 months (24-51 months) underwent ASCR with fascia lata autograft. There was a significant improvement in VAS (7.7-0.7), Constant score (36.0-78.7), forward elevation (115°-171°), external rotation (33°-50°), strength (0.3 kg-2.3 kg), and acromiohumeral distance (6.1 mm-8.6 mm) (P < 0.001). Graft failure was present in 13.8% of patients, as shown by magnetic resonance imaging (26 patients) or ultrasound (3 patients). Patients with failed ASCR showed worse Constant scores (68.5.8 vs 80.2, P = 0.007), worse VAS (2.5 vs 0.4, P = 0.00002), worse external rotation (20° vs 54°, P = 0.004), lower acromiohumeral distance (5mm vs 9mm, P = 0.007), and a high association with the presence of os acromiale (χ²P = 0.003). No revision or subsequent surgical procedures were required.

CONCLUSIONS

ASCR, with autologous fascia lata and single lateral row configuration, is an effective option in irreparable rotator cuff tears and results in clinical and radiologic improvement.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Difference in the results of repair made with single or double rows according to the shape and size of the tear in arthroscopic rotator cuff surgery

The aim of this study was to evaluate the effect on the results of patients applied with arthroscopic full layer total layer rotator cuff repair made according to the shape and size of the tear.The study included a total of 120 patients applied with arthroscopic full layer rotator cuff repair as single or double row repair. The patients were separated into 3 groups of 40 according to the shape of the tear, as Group A (crescent type), Group B (U type), and Group C (L type).The mean age of the whole sample was 66.68 ± 6.86 years (range, 50-81 years). A statistically significant difference was determined between the groups in respect of constant murley (CM), American shoulder and elbow surgeons score (ASES), and University of California Los Angeles score (UCLA) scores (P < .05). The scores of Group A of all the scales were found to be higher than those of Group C (P < .05). In single row and double row repair of small and medium-sized tears of all shapes, no significant difference was determined in respect of the CM and UCLA scores (P > .05).No significant difference was determined between single and double row repair of crescent type tears of all sizes. In large U-shaped tears, the CM, ASES, and UCLA scores were determined to be high in double row repair.

Intratendinous Strain Variations of the Supraspinatus Tendon Depending on Repair Technique: A Biomechanical Analysis Regarding the Cause of Medial Cuff Failure

BACKGROUND

Double-row (DR) and transosseous-equivalent (TOE) techniques for rotator cuff repair offer more stability and promote better tendon healing compared with single-row (SR) repairs and are preferred by many surgeons. However, they can lead to more disastrous retear patterns with failure at the medial anchor row or the musculotendinous junction. The biomechanics of medial cuff failure have not been thoroughly investigated thus far.

PURPOSE

To investigate the intratendinous strain distribution within the supraspinatus tendon depending on repair technique.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twelve fresh-frozen cadaveric shoulders were used. The intratendinous strain within the supraspinatus tendon was analyzed in 2 regions-(1) at the footprint at the greater tuberosity and (2) medial to the footprint up to the musculotendinous junction-using a high-resolution 3-dimensional camera system. Testing was performed at submaximal loads of 40 N, 60 N, and 80 N for intact tendons, after SR repair, after DR repair, and after TOE repair.

RESULTS

The tendon strain of the SR group differed significantly in both regions from that of the intact tendons and the TOE group at 40 N (P≤ .043) and from the intact tendons, the DR group, and the TOE group at 60 N and 80 N (P≤ .048). SR repairs showed more tendon elongation at the footprint and less elongation medial to the footprint. DR and TOE repairs did not provide significant differences in tendon strain when compared with the intact tendons. However, the increase in tendon strain medial to the footprint from 40 N to 80 N was significantly more pronounced in the DR and TOE group (P≤ .029).

CONCLUSION

While DR and TOE repair techniques more closely reproduced the strains of the supraspinatus tendon than did SR repair in a cadaveric model, they showed a significantly increased tendon strain at the musculotendinous junction with higher loads in comparison with the intact tendon.

CLINICAL RELEVANCE

DR and TOE rotator cuff reconstructions lead to a more anatomic tendon repair. However, their use has to be carefully evaluated whenever tendon quality is diminished, as they lead to a more drastic increase in tendon strain medial to the footprint, putting these repairs at risk of medial cuff failure.

Fixationssysteme und Techniken zur arthroskopischen Rotatorenmanschettenrekonstruktion

Arthroskopische Rotatorenmanschettenrekonstruktionen wurden initial mit einer einreihigen („single row“) Technik beschrieben. Im Rahmen technischer Weiterentwicklungen der arthroskopischen Chirurgie wurden diverse Techniken zur zweireihigen („double row“), transossären und transossär-äquivalenten Sehnenfixation entwickelt, nicht zuletzt durch eine zunehmende Verbreitung knotenloser Anker. Die klinischen Ergebnisse zeigen keine relevanten Unterschiede zwischen den jeweiligen Techniken. Biomechanisch sind zweireihige Rekonstruktionen jedoch durch Vergrößerung der Kontaktfläche an der Insertionsstelle und der erreichten Stabilität überlegen, insbesondere mit medial geknoteten Fäden, welche in eine laterale Reihe als sog. Suture-Bridge abgespannt werden. Klassischerweise wurden Schraubanker aus Metall für eine arthroskopische Sehnenfixierung verwendet. Im Laufe der letzten Jahre wurde das Anker-Portfolio jedoch durch moderne bioresorbierbare und nichtresorbierbare (PEEK) Schraub- und Einschlaganker sowie auch um reine Fadenanker (All-suture) erweitert. Ein allgemeingültiger Goldstandard für die Ankerverwendung existiert bis dato nicht, wobei die meisten gängigen Anker – zumindest bei guter Knochenqualität – ausreichende Stabilität gewährleisten. Beim Nahtmaterial kam es ebenso zu relevanten Weiterentwicklungen, sodass dem Versagen der Nähte heutzutage weniger Bedeutung zukommt. Das Aufkommen von bandartigem Nahtmaterial (Tapes) konnte in diversen biomechanischen Studien seine Überlegenheit nachweisen, jedoch ist bei geknoteten Techniken mit Tapes aufgrund des womöglich negativen Einflusses durch größere Knoten Vorsicht geboten. Nicht zuletzt ist die mediale Stichposition möglichst nahe des Rotatorenkabels von großer Bedeutung, da der häufigste Versagensmechanismus einer Rotatorenmanschettenrekonstruktion mit modernem Naht- und Ankermaterial weiterhin ein Hindurchschneiden der Fäden durch das vorgeschädigte Sehnengewebe ist.

Update on all-arthroscopic vs. mini-open rotator cuff repair: A systematic review and meta-analysis

Purpose

To provide an updated comparison between modern arthroscopic and mini-open repairs for treating rotator cuff tears.

Methods

Multiple online databases were searched from 2010 to October 1st, 2020. A meta-analysis was conducted for patient-reported outcomes and complications.

Results

Eleven studies were included. Majority of patients underwent mini-open repair (MOR) compared to arthroscopic repair (AR) (57.4% vs 42.6%). A meta-analysis found statistically significant differences (p < 0.05) in patient-reported outcomes favouring AR. While retear rates were higher in AR (p = 0.03) analysis of retear rates for arthroscopic double row and mini-open repairs, yielded no differences between groups (p = 0.48).

Conclusion

Patients undergoing AR for rotator cuff tears had improved post-operative clinical outcomes in some functional outcomes compared to MOR. Modern arthroscopic double row repair result in similar failure rates to open repair techniques.

Level of evidence

Level III, Systematic Review of Level I-III studies.

Arthroscopic Reduction and Fixation With a Knotless Double-Row Construct Provides Good Results for Displaced Greater Tuberosity Fractures

Purpose

The purpose of the study is to describe the functional and structural outcomes of the arthroscopic 4-strand, knotless, double-row construct with suture tapes for the surgical treatment of displaced and/or comminuted greater tuberosity fractures of the humerus.

Methods

Patients were enrolled between December 2012 and January 2018. The main inclusion criteria were a comminuted and/or displaced tuberosity fracture with a displacement of at least 5 mm in any plane fixed under arthroscopy using a 4-strand, knotless, double-row construct. The technique involves reducing the displaced fragment with 2 medially placed, transtendinous anchors and compressing the greater tuberosity using the tapes from these medial anchors in 2 laterally placed anchors. The exclusion criteria were a fracture that was more than 10 days old at the time of surgery or a history of shoulder surgery and 3- or 4-part fractures. The postoperative rehabilitation protocol was similar for all patients. Constant scores, Quick Dash, return to work and sport, and complications were reported after a minimum follow-up period of 24 months. Bone healing was systematically evaluated on standardized radiographs, including lateral scapula view and anteroposterior views.

Results

Twenty-one patients were enrolled in this study. One patient did not complete the follow-up examination period and thus was excluded, leaving 20 patients in this study. At a median (SD) follow-up of 32 (9) months, the median (SD) Constant score was 94.7 (7.3) points, the median (SD) Quick Dash was 1.7 (4) points, and median (SD) visual analog scale score was 0.5 (1.4). All patients returned to previous work and sport level. No malunions or nonunions were seen. One conversion to open surgery was required for failure of the lateral row during surgery in a 62-year-old woman with osteopenic bone. Two patients experienced complex regional pain syndrome in the postoperative period that resolved after nonoperative treatment.

Conclusions

In this series, the use of arthroscopy combined with the biomechanical properties of knotless double-row constructs contributed to postoperative satisfactory functional results and healing of greater tuberosity fracture. In addition, range of motion was early, and no hardware removal was required. However, care should be taken with osteopenic bone where anchorage can fail.

Level of Evidence

Level IV, case series.

Biomechanical comparison between single-row with triple-loaded suture anchor and suture-bridge double-row rotator cuff repair

BACKGROUND

Numerous biomechanical and clinical studies comparing different techniques for rotator cuff repair have been reported, yet universal consensus regarding the superior technique has not achieved. A medially-based single-row with triple-loaded suture anchor (also referred to as the Southern California Orthopedic Institute [SCOI] row) and a suture-bridge double-row (SB-DR) with Push-Locks have been shown to result in comparable improvement in treating rotator cuff tear, yet the biomechanical difference is unknown. The purpose of the current study was to determine whether a SCOI row repair had comparable initial biomechanical properties to a SB-DR repair.

METHODS

Six matched pairs of fresh-frozen cadaveric shoulders with full-thickness supraspinatus tendon tears we created were included. Two different repairs were performed for each pair (SCOI row and SB-DR methods). Specimens were mounted on a material testing machine to undergo cyclic loading, which was cycled from 10 to 100 N at 1 Hz for 500 cycles. Construct gap formation was recorded at an interval of 50 cycles. Samples were then loaded to failure and modes of failure were recorded. Repeated-measures analysis of variance and pair-t test were used for statistical analyses.

RESULTS

The construct gap formation did not differ between SCOI row and SB-DR repairs (P = 0.056). The last gap displacement was 1.93 ± 0.37 mm for SCOI row repair, and 1.49 ± 0.55 mm for SB-DR repair. The tensile load for 5 mm of elongation and ultimate failure were higher for SCOI row repair compared to SB-DR repair (P = 0.011 and 0.028, respectively). The ultimate failure load was 326.34 ± 11.52 N in the SCOI row group, and 299.82 ± 27.27 N in the SB-DR group. Rotator cuff repair with the SCOI row method failed primarily at the suture- tendon interface, whereas pullout of the lateral row anchors was the primary mechanism of failure for repair with the SB-DR method.

CONCLUSION

Rotator cuff repair with the SCOI row method has superior biomechanical properties when compared with the SB-DR method. Therefore, SCOI row repair using a medially-based single-row technique with triple-loaded suture anchor is recommended to improve the initial strength in treating full-thickness rotator cuff tears.

Linked Double-Row Equivalent Arthroscopic Rotator Cuff Repair Leads to Significantly Improved Patient Outcomes

Background:

Biomechanical studies have demonstrated that arthroscopic rotator cuff repair using a linked double-row equivalent construct results in significantly higher load to failure compared with conventional transosseous-equivalent constructs.

Purpose:

To determine the patient-reported outcomes (PROs), reoperation rates, and complication rates after linked double-row equivalent rotator cuff repair for full-thickness rotator cuff tears.

Study Design:

Case series; Level of evidence, 4.

Methods:

Consecutive patients who underwent linked double-row equivalent arthroscopic rotator cuff repair with minimum 2-year follow-up were included. The primary outcome was the American Shoulder and Elbow Surgeons (ASES) score at final follow-up. Secondary outcomes included the Simple Shoulder Test (SST), shortened Disabilities of the Arm, Shoulder and Hand (QuickDASH) questionnaire, visual analog scale (VAS), reoperations, and complications. Clinical relevance was defined by the minimally clinically important difference (MCID). Comparisons on an individual level that exceeded MCID (individual-level scores) were deemed clinically relevant. Comparisons between preoperative and postoperative scores were completed using the Student t test. All P values were reported with significance set at P < .05.

Results:

A total of 42 shoulders in 41 consecutive patients were included in this study (21 male patients [51.2%]; mean age, 64.5 ± 11.9 years; mean follow-up, 29.7 ± 4.5 months). All patients (100%) completed the minimum 2-year follow-up. The rotator cuff tear measured on average 15.2 ± 8.9 mm in the coronal plane and 14.6 ± 9.8 mm in the sagittal plane. The ASES score improved significantly from 35.5 ± 18.2 preoperatively to 93.4 ± 10.6 postoperatively (P < .001). The QuickDASH (P < .001), SST (P < .001), and VAS (P < .001) scores also significantly improved after surgery. All patients (42/42 shoulders; 100%) achieved clinically relevant improvement (met or exceeded MCID) on ASES and SST scores postoperatively. There were no postoperative complications (0.0%) or reoperations (0.0%) at final follow-up.

Conclusion:

Arthroscopic repair of full-thickness rotator cuff tears with the linked double-row equivalent construct results in statistically significant and clinically relevant improvements in PRO scores with low complication rates (0.0%) and reoperation rates (0.0%) at short-term follow-up.

Improved Rotator Cuff Footprint Contact Characteristics With an Augmented Repair Construct Using Lateral Edge Fixation

BACKGROUND

The transosseous-equivalent (TOE) rotator cuff repair construct has become the gold standard for the repair of medium and large rotator cuff tears. Repair failure, however, continues to be a problem. One contributing factor may be the inability of the TOE repair to replicate the native footprint contact characteristics during shoulder movement, especially in rotation. This results in higher strain across the repair, which leads to gapping and predisposes the construct to failure. In an effort to better reproduce the native compression forces throughout the footprint, an augmented TOE construct supplemented with lateral edge fixation is proposed, and the contact characteristics were compared with those of the gold standard TOE construct.

HYPOTHESIS

The augmented TOE repair will demonstrate improved footprint contact characteristics when compared with the classic TOE repair.

STUDY DESIGN

Controlled laboratory study.

METHODS

Ten fresh-frozen cadaveric shoulders underwent supraspinatus repair using both the classic TOE double-row construct and the augmented TOE repair. For the augmented repair, 2 luggage tag sutures were used to secure the lateral edge and incorporated into the lateral row anchors. A Tekscan pressure sensor (Tekscan Inc) placed under the repaired tendon was used to collect footprint contact area, force, peak pressure, and contact pressure data for each construct.

RESULTS

The augmented construct demonstrated significantly greater contact forces (average difference, 4.9 N) and significantly greater contact pressures (average difference, 23.1 kPa) at all degrees of abduction and all degrees of rotation. At 30° of internal and 30° of external rotation at both 0° and 30° of shoulder abduction, the augmented construct demonstrated significantly greater peak contact pressures.

CONCLUSION

The augmented construct showed superior contact characteristics when compared with the classic TOE technique. The addition of lateral edge fixation to the classic TOE repair significantly improves bone-tendon contact characteristics with minimal additional surgical effort.

CLINICAL RELEVANCE

The results of this study indicate that lateral augmentation of the classic TOE repair produces a biomechanically superior construct that may optimize tendon healing.

Medialization of medial row anchor via the Nevasier portal yield enhanced footprint and outcomes in medium-to-large rotator cuff tears

PURPOSE

To evaluate clinical and radiological outcomes of medial row anchor insertion between 90° or 45° (deadman) angle in the suture-bridge rotator cuff repair of medium-to-large rotator cuff tears.

METHODS

This retrospective analysis included 113 consecutive patients undergoing arthroscopic suture-bridge repair for medium-to-large rotator cuff tears (mean tear size: 2.8 × 2.3 cm) between 2010 and 2013. The patients were divided into two groups: group I (53 patients) and group II (60 patients) involving 90° and 45° medial row anchors, respectively. The conventional lateral row anchors were inserted in the suture-bridge repair. The clinical outcomes at 2 years and radiological outcomes including re-tear or footprint coverage (anteroposterior length and mediolateral width) of the repaired tendon using postoperative MRI were evaluated.

RESULTS

Clinical outcome scores were significantly improved in both groups. However, Group I (90° anchor insertion group) showed better clinical scores without the difference of range of motion. The postoperative MRI revealed enlarged footprint coverage with 90° medial row anchor. The repaired footprint cuff size (mediolateral width) in the coronal plane MRI showed a statistically significant difference (45°: 19 mm vs. 90°: 24 mm) (p < 0.05).

CONCLUSIONS

Enhanced clinical outcomes and additional anatomical footprint coverage (coronal width of repaired tendon) in the suture-bridge repair are obtained with the 90° medial row anchors compared with the 45° medial row anchors. These findings would guide clinical application of 90° medial row anchor insertion for further medialization in the medium-to-large rotator cuff tears.

LEVEL OF EVIDENCE

Level III (retrospective comparative trial).

Current Concepts in Rotator Cuff Repair Techniques: Biomechanical, Functional, and Structural Outcomes

There is substantial evidence indicating that double-row (DR) repair restores more of the anatomic rotator cuff footprint and is biomechanically superior to single-row (SR) repair. Transosseous-equivalent (TOE) techniques have shown biomechanical advantages when compared with traditional DR, including increased contact at the rotator cuff footprint, higher pressure at the tendon-bone interface, and increased failure strength. Several meta-analyses of evidence level 1 and 2 studies have shown a lower rate of failed/incomplete healing when DR repair was compared with SR repair types. There is some limited evidence that TOE techniques improve healing rates in large and massive tears as compared with SR and DR. Overall, most level 1 and 2 studies have failed to prove a significant difference between SR and DR repairs in terms of clinical outcomes. However, most studies include only short-term follow-up, minimizing the impact that the higher rate of retears/failed healing seen with SR repairs can have in the long term. There are no high-quality clinical studies comparing different DR configurations, and there are currently not enough clinical data to determine the functional advantages of various DR technique modifications over one another. Although numerous biomechanical and clinical studies comparing different rotator cuff repair techniques have been published in the past decade, none has achieved universal acceptance. It is essential for the orthopaedic surgeon to know in detail the available literature to be able to apply the most appropriate and cost-effective technique in terms of healing and functional outcomes. This review provides a critical analysis of the comparative biomechanical and clinical studies among SR, DR, and TOE techniques reported in the literature in the past decade.

Is Arthroscopic Transosseous Rotator Cuff Repair Strength Dependent on the Tunnel Angle?

Background

Previous studies have aimed to biomechanically improve the transosseous tunnel technique of rotator cuff repair. However, no previous work has addressed tunnel inclination at the time of surgery as an influence on the strength of the repair construct.

Hypothesis

We hypothesized that the tunnel angle and entry point would influence the biomechanical strength of the transosseous tunnel in rotator cuff repair. Additionally, we investigated how tunnel length and bone quality affect the strength of the repair construct.

Study Design

Controlled laboratory study.

Methods

Mechanical testing was performed on 10 cadaveric humeri. Variations in the bone tunnel angle were imposed in the supraspinatus footprint to create lateral tunnels with inclinations of 30°, 45°, and 90° relative to the longitudinal axis of the humeral shaft. A closed loop of suture was passed through the bone tunnel, and cyclic loading was applied until failure of the construct. Load to failure and distance between entry points were the dependent variables. Analysis of variance, post hoc paired t tests, and the Bonferroni correction were used to analyze the relationship between the tunnel angle and failure load. The Pearson correlation coefficient was then used to evaluate the correlation of the distance between entry points to the ultimate failure load, and t tests were used to compare failure loads between healthy and osteoporotic bone.

Results

Tunnels drilled perpendicularly to the longitudinal axis (90°) achieved the highest mean failure load (167.51 ± 48.35 N). However, there were no significant differences in the failure load among the 3 tested inclinations. Tunnels drilled perpendicularly to the longitudinal axis (90°) measured 13.86 ± 1.35 mm between entry points and were significantly longer (P = .03) than the tunnels drilled at 30° and 45°. We found no correlation of the distance between entry points and the ultimate failure load. Within the scope of this study, we could not identify a significant effect of bone quality on failure load.

Conclusion

The tunnel angle does not influence the strength of the bone-suture interface in the transosseous rotator cuff repair construct.

Clinical Relevance

The transosseous technique has gained popularity in recent years, given its arthroscopic use. These findings suggest that surgeons should not focus on the tunnel angle as they seek to maximize repair strength.

Evaluating strategies and outcomes following rotator cuff tears

INTRODUCTION

Rotator cuff tear surgical repair techniques have significantly progressed. However, tendon retear following primary repair persistently occurs at high rates. Rehabilitation protocols, surgical fixation techniques, biologic therapy with scaffolds, platelet-rich plasma, and even stem cell applications are under study to promote adequate tendon healing.

METHODS

A nonsystematic query of the PubMed database was conducted in July 2016 utilizing the search terms "rotator cuff repair," "tear," "rehabilitation," "scaffold," "platelet-rich plasma," and "stem cell" to identify, analyze, and summarize relevant studies.

CONCLUSION

Individualized rehabilitation protocols may be the best approach for small to medium sized tears. Surgical fixation will continue to be debated as modifications to single-row technique and increases in suture number have improved tensile strength. Double-row repairs have been associated with higher costs. Transosseous equivalent technique exhibits comparable subjective and objective outcomes to single- and double-row repair at two-year follow-up. Biocompatible scaffold augmentation has showed inconsistent short-term results. Platelet-rich plasma has lacked uniformity in treatment preparation, administration, and outcome measurement with mixed results. Few human studies have suggested decreased retear rates and improved repair maintenance following bone marrow-derived mesenchymal stem cell augmentation. This review reiterated the necessity of additional high-quality, large-sample studies to develop any final verdict regarding efficacy.

Arthroscopic double-row rotator cuff repair: a comprehensive review of the literature

Rotator cuff repairs seek to achieve adequate tendon fixation and to secure the fixation during the process of biological healing. Currently, arthroscopic rotator cuff repair has become the gold standard. One of the earliest defined techniques is single-row repair but the inadequacy of single-row repair to precisely restore the anatomical footprint as well as the significant rates of retear especially in large tears have led surgeons to seek other techniques. Double-row repair techniques, which have been developed in response to these concerns, have various modifications like the number and placement of anchors and suture configurations.

When the literature is reviewed, it is possible to say that double-row repairs demonstrate superior biomechanical properties. In regard to retear rates, both double row and transosseous equivalent (TOE) techniques have also yielded more favorable outcomes compared to single-row repair. But the clinical results are conflicting and more studies have to be conducted. However, it is more probable that superior structural integrity will yield better structural and functional results in the long run. TOE repair technique is regarded as promising in terms of better biomechanics and healing since it provides better footprint contact. Knotless TOE structures are believed to reduce impingement on the medial side of tendons and thus aid in tendon nutrition; however, there are not enough studies about its effectiveness.

It is important to optimize the costs without endangering the treatment of the patients. We believe that the arthroscopic TOE repair technique will yield superior results in regard to both repair integrity and functionality, especially with tears larger than 3 cm. Although defining the pattern of the tear is one of the most important guiding steps when selecting the repair technique, the surgeon should not forget to evaluate every patient individually for tendon healing capacity and functional expectations.

Rotator Cuff Repair: Single Row Repair Versus Double Row Repair and Superior Capsular Reconstruction

The surgical management of rotator cuff (RC) tears has progressed considerably in recent decades. Arthroscopic procedures now represent the mainstay of contemporary treatment approaches. The success of repair is predicated upon the achievement of a secure, durable repair that promotes tendon-to-bone healing. Both single and double row (DR) suture anchor configurations have been described to achieve stable fixation. Although consensus is lacking with regard to the clinical superiority of one configuration over another, trends in the literature suggest that DR repairs may optimize the likelihood of tendon healing and restoration of shoulder strength. In cases of truly irreparable RC tears, superior capsular reconstruction is a promising alternative to open tendon transfer and arthroplasty procedures. The purposes of this concise review are to: (1) explain our preference for a DR repair configuration in almost all circumstances; and (2) advocate superior capsular reconstruction as a viable treatment tactic for truly irreparable RC tears in the absence of significant glenohumeral arthritis.

Double-Layer Rotator Cuff Repair: Anatomic Reconstruction of the Superior Capsule and Rotator Cuff Improves Biomechanical Properties in Repairs of Delaminated Rotator Cuff Tears

BACKGROUND

Delamination in rotator cuff tears has been identified as a prognostic factor for negative outcome after repair, with a reported prevalence between 38% and 88%.

PURPOSE

To compare biomechanical properties of 3 repair techniques for delaminated rotator cuff tears.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eighteen fresh-frozen cadaveric shoulders were used to evaluate rotator cuff footprint reconstruction, contact area and pressure, displacement under cyclical loading, and load to failure of 3 double-row repair configurations: double-row suture repair with medial row knots (medially knotted bridge, mkB); knotless double-row repair using suture tapes (knotless bridge, klB); and knotless double-row, double-layer-specific repair (double-layer, DL). Dynamic pressure sensors were used to assess contact patterns at the footprint region in 0°, 30°, and 60° of glenohumeral abduction and 5 rotational positions (0°, 30° of internal rotation, 30° of external rotation, 60° of internal rotation, 60° of external rotation). Optical markers were used to document whole tendon and individual layer displacement after rotator cuff repair under cyclical loading for 200 cycles (10 N to 100 N at 1 Hz). Specimens were then loaded monotonically to failure at a rate of 33 mm/min.

RESULTS

Mean contact area and footprint restoration were highest in the DL group at 60° of glenohumeral abduction for all rotational positions (mkB mean ± SD, 195.4 ± 54.3 mm², 66.7% ± 19.7%; klB, 250.6 ± 34.9 mm², 76.2% ± 10.3%; DL, 318.4 ± 36.6 mm², 109.1% ± 24.0%; P < .001). The double-layer-specific repair showed the least displacement under cyclical loading (mkB mean ± SD, 0.53 ± 0.18 mm; klB, 0.79 ± 0.37 mm; DL, 0.31 ± 0.24 mm; P = .029), most closely resembling the native tendon. Peak loads at failure were comparable between repair groups (mkB mean ± SD, 366.92 ± 70.59 N; klB, 280.05 ± 77.66 N; DL, 398.35 ± 109.04 N; P = .083).

CONCLUSION

Anatomic restoration of the superior capsular and tendon insertion in delaminated rotator cuff tears with a double-layer-specific repair configuration demonstrated superior footprint restoration with increasing abduction, while providing construct displacement comparable to the native tendon under cyclical loading. Peak load at failure was comparable between repair constructs.

CLINICAL RELEVANCE

The prevalence and clinical importance of delaminated rotator cuff tears have long been underestimated. Anatomically correct individual reconstruction of the superior capsule and rotator cuff could restore near-native biomechanics and potentially reduce the risk of rotator cuff repair failure.

Comparison of functional results of two fixation systems using single-row suturing of rotator cuff

INTRODUCTION

Arthroscopic repair of rotator cuff disorders is a technically demanding but successful procedure. Many anchor and suture alternatives are now available. The choice of the implant by the surgeon is less important than the configuration of the suture used to fix the tendon, however it is necessary to know if there are differences in the results, using each one of them. The aim of the study is to evaluate if there are differences between the knotted and non-knotted implant in terms of functional and satisfaction results.

MATERIAL AND METHODS

A retrospective study was carried out on 83 patients operated between 2010 and 2014 in our center using 2anchoring systems with and without knotting (39 versus 44 patients respectively), with single row in complete rupture of the rotator cuff.

RESULTS

At the end of the follow-up, an average score was obtained on the Constant scale of 74.6 points. 98% of the patients considered the result of the surgery satisfactory. Statistically, there were no significant differences between the 2groups in terms of functionality, satisfaction or reincorporation to activities.

DISCUSSION AND CONCLUSIONS

The functional results of the single-row cuff suture are satisfactory, although biomechanical studies show advantages in favor of sutures that reproduce a transoseo system. It our series of patients the presence of knotting does not show per se a significant functional difference being both superimposable techniques in absolute values of functionality and patient satisfaction.

[Arthroscopic rotator cuff surgery : New and established methods]

This present article summarizes established and current developments and aspects of rotator cuff surgery. Achieved milestones as well as current approaches are presented and assessed with respect to their clinical and radiographic impact. Despite biomechanical and technical improvements in modern rotator cuff repair techniques, re-defect and re-tearing rates could not be fully eliminated. Meanwhile, the importance of biological processes around successful tendon-bone reintegration has been increasingly recognized. Hence, this article presents the current scientific standing regarding biological growth factors, platelet-rich plasma and rotator cuff augmentation techniques (with allogenic/autologous grafts). In summary, there are clear biomechanical advantages as well as many promising approaches to biological augmentation; however, the latter have not yet been transferred into regular clinical application.

Arthroscopic Single-Row Versus Double-Row Suture Bridge Technique for Rotator Cuff Tears in Patients Younger Than 55 Years: A Prospective Comparative Study

BACKGROUND

When arthroscopic rotator cuff repair is performed on a young patient, long-lasting structural and functional tendon integrity is desired. A fixation technique that potentially provides superior tendon healing should be considered for the younger population to achieve long-term clinical success. Hypothesis/Purpose: The purpose was to compare the radiological and clinical midterm results between single-row and double-row (ie, suture bridge) fixation techniques for arthroscopic rotator cuff repair in patients younger than 55 years. We hypothesized that a double-row technique would lead to improved tendon healing, resulting in superior mid- to long-term clinical outcomes.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A consecutive series of 66 patients younger than 55 years with a medium to large full-thickness tear of supraspinatus and infraspinatus tendons who underwent arthroscopic single-row or double-row (ie, suture bridge) repair were enrolled and prospectively observed. Thirty-four and 32 patients were assigned to single-row and double-row groups, respectively. Postoperatively, tendon integrity was assessed by MRI following Sugaya's classification at a minimum of 12 months, and clinical outcomes were assessed with the Constant score and the University of California, Los Angeles (UCLA) score at a minimum of 2 years.

RESULTS

Mean follow-up time was 46 months (range, 28-50 months). A higher tendon healing rate was obtained in the double-row group compared with the single-row group (84% and 61%, respectively [ P < .05]). Although no difference in outcome scores was observed between the 2 techniques, patients with healed tendon demonstrated superior clinical outcomes compared with patients who had retorn tendon (UCLA score, 34.2 and 27.6, respectively [ P < .05]; Constant score, 94 and 76, respectively [ P < .05]).

CONCLUSION

The double-row repair technique potentially provides superior tendon healing compared with the single-row technique. Double-row repair should be considered for patients younger than 55 years with medium to large rotator cuff tears.

V-shaped double-row distal triceps tendon repair: a novel technique using unicortical button fixation

Background

This report was designed to present a novel technique combining suture anchor and unicortical button fixation for distal triceps tendon repair.

Technical description

For anatomical reinsertion of an acute distal triceps tendon rupture, two suture anchors and one unicortical button forming a V-shaped configuration were used. The operative approach is described in detail.

Results

Excellent clinical and functional results were achieved in the early postoperative phase. The patient reached full elbow range of motion and extension muscle strength (5/5) compared to the uninjured arm 12 weeks after surgery. Complications did not occur.

Conclusion

This is the first report using unicortical button fixation in distal triceps tendon repair with promising preliminary results.

Level of evidence

Technical description, case report, Level V

Perfusion of the Rotator Cuff Tendon According to the Repair Configuration Using an Indocyanine Green Fluorescence Arthroscope: A Preliminary Report

BACKGROUND

The disturbance of rotator cuff tendon perfusion has been connected with the suture-bridge configuration repair (SBCR) technique; however, in vivo assessments of the tendon blood supply have been problematic with other modalities. An evaluation of tissue perfusion by an indocyanine green (ICG) fluorescence arthroscope has been developed to counteract this difficulty.

PURPOSE

To verify the hindrance of perfusion in SBCR, we used an ICG fluorescence camera to compare parallel-type transosseous repair (PTR) and SBCR in rabbits immediately and at 3 days after rotator cuff repair.

STUDY DESIGN

Controlled laboratory study.

METHODS

Acute rotator cuff repair was performed on the shoulders of 10 rabbits. Both shoulders were repaired using either PTR or SBCR. For PTR, simple repair was performed through 2 parallel transosseous tunnels created using a microdrill. For SBCR, 2 additional crisscross transosseous tunnels were added to mimic arthroscopic SBCR. Immediately after repair, ICG was injected through the ear vein, and images were recorded using an ICG fluorescence camera. Tendon perfusion was compared by measuring fluorescence intensity using ImageJ software in both methods. At 3 days after rotator cuff repair, a reassessment of ICG fluorescence was performed. In addition, as a subsidiary study, a comparison of each repair method and a healthy tendon was performed (PTR vs healthy tendon and SBCR vs healthy tendon). Six rabbits (3 for each comparison) were included.

RESULTS

Immediately after rotator cuff repair, the mean (±SD) grayscale intensity of ICG fluorescence was weaker in SBCR than PTR in 10 specimens (65.9 ± 47.6 vs 84.3 ± 53.4 per pixel, respectively; P = .003). At 3 days after repair, 8 specimens were included in the analysis because suture strands failed in 2 specimens in SBCR. The mean intensity of fluorescence was still weaker in SBCR compared with PTR (52.5 ± 13.7 vs 60.2 ± 22.7 per pixel, respectively; P = .077). The mean fluorescence intensity compared with a healthy tendon was 83.2% ± 9.5% in PTR and 63.2% ± 13.2% in SBCR.

CONCLUSION

Our ICG fluorescence camera system was able to detect ICG fluorescence in an acute rabbit rotator cuff repair model. SBCR showed inferior tendon perfusion immediately after repair. At 3 days after repair, SBCR still showed inferior fluorescence intensity, although it did not reach statistical significance.

CLINICAL RELEVANCE

In this study, SBCR hindered perfusion at the tendon in the compressed area. This finding may affect rotator cuff tendon healing and failure mode.

Evaluation and treatment of internal impingement of the shoulder in overhead athletes

One of the most common pathologic processes seen in overhead throwing athletes is posterior shoulder pain resulting from internal impingement. “Internal impingement” is a term used to describe a constellation of symptoms which result from the greater tuberosity of the humerus and the articular surface of the rotator cuff abutting the posterosuperior glenoid when the shoulder is in an abducted and externally rotated position. The pathophysiology in symptomatic internal impingement is multifactorial, involving physiologic shoulder remodeling, posterior capsular contracture, and scapular dyskinesis. Throwers with internal impingement may complain of shoulder stiffness or the need for a prolonged warm-up, decline in performance, or posterior shoulder pain. On physical examination, patients will demonstrate limited internal rotation and posterior shoulder pain with a posterior impingement test. Common imaging findings include the classic “Bennett lesion” on radiographs, as well as articular-sided partial rotator cuff tears and concomitant SLAP lesions. Mainstays of treatment include intense non-operative management focusing on rest and stretching protocols focusing on the posterior capsule. Operative management is variable depending on the exact pathology, but largely consists of rotator cuff debridement. Outcomes of operative treatment have been mixed, therefore intense non-operative treatment should remain the focus of treatment.

Optimal Lateral Row Anchor Positioning in Posterior-Superior Transosseous Equivalent Rotator Cuff Repair: A Micro-Computed Tomography Study

Background:

The optimal placement of suture anchors in transosseous-equivalent (TOE) double-row rotator cuff repair remains controversial.

Purpose:

A 3-dimensional (3D) high-resolution micro–computed tomography (micro-CT) histomorphometric analysis of cadaveric proximal humeral greater tuberosities (GTs) was performed to guide optimal positioning of lateral row anchors in posterior-superior (infraspinatus and supraspinatus) TOE rotator cuff repair.

Study Design:

Descriptive laboratory study.

Methods:

Thirteen fresh-frozen human cadaveric proximal humeri underwent micro-CT analysis. The histomorphometric parameters analyzed in the standardized volumes of interest included cortical thickness, bone volume, and trabecular properties.

Results:

Analysis of the cortical thickness of the lateral rows demonstrated that the entire inferior-most lateral row, 15 to 21 mm from the summit of the GT, had the thickest cortical bone (mean, 0.79 mm; P = .0001), with the anterior-most part of the GT, 15 to 21 mm below its summit, having the greatest cortical thickness of 1.02 mm (P = .008). There was a significantly greater bone volume (BV; posterior, 74.5 ± 27.4 mm³; middle, 55.8 ± 24.9 mm³; anterior, 56.9 ± 20.7 mm³; P = .001) and BV as a percentage of total tissue volume (BV/TV; posterior, 7.3% ± 2.7%, middle, 5.5% ± 2.4%; anterior, 5.6% ± 2.0%; P = .001) in the posterior third of the GT than in intermediate or anterior thirds. In terms of both BV and BV/TV, the juxta-articular medial row had the greatest value (BV, 87.3 ± 25.1 mm³; BV/TV, 8.6% ± 2.5%; P = .0001 for both) followed by the inferior-most lateral row 15 to 21 mm from the summit of the GT (BV, 62.0 ± 22.7 mm³; BV/TV, 6.1% ± 2.2%; P = .0001 for both). The juxta-articular medial row had the greatest value for both trabecular number (0.3 ± 0.06 mm^–1; P = .0001) and thickness (0.3 ± 0.08 μm; P = .0001) with the lowest degree of trabecular separation (1.3 ± 0.4 μm; P = .0001). The structure model index (SMI) has been shown to strongly correlate with bone strength, and this was greatest at the inferior-most lateral row 15 to 21 mm from the summit of the GT (2.9 ± 0.9; P = .0001).

Conclusion:

The inferior-most lateral row, 15 to 21 mm from the tip of the GT, has good bone stock, the greatest cortical thickness, and the best SMI for lateral row anchor placement. The anterior-most part of the GT 15 to 21 mm below its summit had the greatest cortical thickness of all zones. The posterior third of the GT also has good bone stock parameters, second only to the medial row. The best site for lateral row cortical anchor placement is 15 to 21 mm below the summit of the GT.

Clinical Relevance:

Optimal lateral anchor positioning is 15 to 21 mm below the summit of the greater tuberosity in TOE.

Biomechanical study comparing 3 fixation methods for rotator cuff massive tear: Transosseous No. 2 suture, transosseous braided tape, and double-row

BACKGROUND

Important rotator cuff repair failure rates have prompted this study of the techniques and materials used in order to optimize clinical results.

QUESTIONS/PURPOSES

Is the reconstruction of the rotator cuff biomechanically stronger when using: 1) transosseous with 2 mm braided tape suture (TOT), 2) transosseous with multi-strand No. 2 sutures (TOS), or 3) double row suture bridge with suture anchors loaded with No. 2 braided sutures (DRSB)?

METHODS

Twenty-four cadaveric pig shoulders were randomized in the three repair constructs. The infraspinatus muscle was detached to mimic a complete laceration, repaired with one of the three repair groups and tested with a traction machine. Cameras recorded tendon displacement during trials. The ultimate strength (US), failure mode, and tendon displacement, qualified by the bare footprint area (BFA), during cycling phases were compared.

RESULTS

The US for DRSB was 175 ± 82 Newton (N), 91 ± 51 N for TOS, and 147 ± 63 N for TOT. The BFA after 200 cycles was 81 ± 34% for TOS, 57 ± 41% for TOT, and 26 ± 27% for DRSB repairs. No significant difference was observed between the DRSB and TOT results for US or BFA percentage of loss during all the cycling phases. TOS proved to be weaker than TOT and DRSB.

CONCLUSION

All the ruptures occurred in the tendon, which seems to be the weakness of rotator cuff repairs. The use of braided tape suture with a transosseous technique seems to be a cost effective, equivalent alternative implant compared to anchor fixation.

Rotator cuff rehabilitation: current theories and practice

A fully functioning, painless shoulder joint is essential to maintain a healthy, normal quality of life. Disease of the rotator cuff tendons (RCTs) is a common issue that affects the population, increasing with age, and can lead to significant disability and social and health costs. RCT injuries can affect younger, healthy patients and the elderly alike, and may be the result of trauma or occur as a result of chronic degeneration. They can be acutely painful, limited to certain activities or completely asymptomatic and incidental findings. A wide variety of treatment options exists ranging from conservative local and systemic pain modalities, to surgical fixation. Regardless of management ultimately chosen, physiotherapy of the RCT, rotator cuff muscles and surrounding shoulder girdle plays an essential role in proper treatment. Length of treatment, types of therapy and timing may vary if therapy is definitive care or part of a postoperative protocol. Allowing time for adequate RCT healing must always be considered when implementing ROM and strengthening after surgery. With current rehabilitation methods, patients with all spectrums of RCT pathology can improve their function, pain and quality of life. This manuscript reviews current theories and practice involving rehabilitation for RCT injuries.

Pull-out stability of anchors for rotator cuff repair is also increased by bio-absorbable augmentation: a cadaver study

INTRODUCTION

Osteoporosis is a highly focused issue in current scientific research and clinical treatment. Especially in rotator cuff repair, the low bone quality of patients suffering from osteoporosis is an important issue. In this context, non-biological solutions using PMMA for anchor augmentation have been developed in the recent past. The aim of this study was to evaluate whether augmentation of suture anchors using bio-absorbable osteoconductive fiber-reinforced calcium phosphate results in improved failure load of suture anchors as well.

MATERIALS AND METHODS

Altogether 24 suture anchors (Corkscrew FT 1 Suture Anchors, Arthrex, Naples, FL, USA) were evaluated by applying traction until pullout in 12 paired fresh frozen human cadaver humeri using a servo-hydraulic testing machine. Inclusion criteria were an age of more than 64 years, a macroscopically intact RC and an intact bone. The anchors were evaluated at the anterolateral and posteromedial aspect of the greater tuberosity. 12 suture anchors were augmented and 12 suture anchors were conventionally inserted.

RESULTS

The failure load was significantly enhanced by 66.8 % by the augmentation method. The fiber-reinforced calcium phosphate could be easily injected and applied.

CONCLUSION

The bio-absorbable cement in this study could be a promising augmentation material for RC reconstructions, but further research is necessary-the material has to be evaluated in vivo.

Rotator cuff tears: Review of epidemiology, clinical assessment and operative treatment

Rotator cuff tears (RTCs) are the most common cause of shoulder disability. There has been a proportional increase in the prevalence of RCT in accordance with the rising trend of an ageing population. In this article we review the current literature encompassing RCT epidemiology, risk factors and aetiopathogenesis. We also summarize the current diagnostic modalities, treatment options, rehabilitation and outcomes.

A 3D finite element model for geometrical and mechanical comparison of different supraspinatus repair techniques

BACKGROUND

Contact pressure and contact area are among the most important mechanical factors studied to predict the effectiveness of a rotator cuff repair. The suture configurations can strongly affect these factors but are rarely correlated with each other. For example, there is a significant difference between the single-row technique and the transosseous or transosseous-like approaches in terms of footprint contact area coverage. A finite element model-based approach is presented and applied to account for various parameters (eg, suture pretension, geometry of the repair, effect of the sutures, geometry of the lesion) and to compare the efficacy of different repair techniques in covering the original footprint.

METHODS

The model allows us to evaluate the effect of parameters such as suture configuration and position and suture pretension. The validity of such an approach was assessed in comparing 3 different repair techniques: single row, transosseous equivalent, and double row.

RESULTS

Results from the application of the models show that the double-row and transosseous-equivalent techniques lead to progressive increase of the contact area compared with the single-row approach, supporting the conclusion that transosseous-equivalent fixation leads to an increase of the contact area and a better distribution of the pressure coverage.

CONCLUSION

The 3-dimensional finite element model approach allows multiple variables to be assessed singularly, weighing the specific influence. Moreover, the approach presented in this study could be a valid tool to predict and to reproduce different configurations, identifying how to reduce the stress over the tendon and when a repair could be effective or not.

Healing disturbance with suture bridge configuration repair in rabbit rotator cuff tear

BACKGROUND

Medial row failure has been reported in the suture bridge technique of rotator cuff repair. This study compared the healing response of suture bridge configuration repair (SBCR) and parallel type transosseous repair (PTR).

METHODS

Acute rotator cuff repair was performed in 32 rabbits. Both shoulders were repaired using PTR or SBCR. In PTR, simple PTR was performed through 2 parallel transosseous tunnels created using a microdrill. In SBCR, 2 additional crisscross transosseous tunnels were added to mimic arthroscopic SBCR. At 1, 2, and 5 weeks postoperatively, comparative biomechanical testing was performed in 8 rabbits, and histologic analysis, including immunohistochemical staining for CD31, was performed in 4 rabbits.

RESULTS

Failure loads at 1 week (38.12 ± 20.43 N vs 52.00 ± 27.23 N; P = .284) and 5 weeks (97.93 ± 48.35 N vs 119.60 ± 60.81 N; P = .218) were not statistically different between the SBCR and PTR groups, respectively, but were significantly lower in the SBCR group than in the PTR group (23.56 ± 13.56 N vs. 44.25 ± 12.53 N; P = .009), respectively, at 2 weeks. Markedly greater fibrinoid deposition was observed in the SBCR group than in the PTR group at 2 weeks. For vascularization, there was a tendency that more vessels could be observed in PTR than in SBCR at 2 weeks (15.9 vs 5.6, P = .068).

CONCLUSIONS

In a rabbit acute rotator cuff repair model, SBCR exhibited inferior mechanical strength, and fewer blood vessels were observed at the healing site at 2 weeks postoperatively. Medial row tendon failure was more common in SBCR. Surgeons should consider the clinical effect of SBCR when performing rotator cuff repair.

Outcomes following arthroscopic transosseous equivalent suture bridge double row rotator cuff repair: a prospective study and short-term results

Background: The transosseous-equivalent cross bridge double row (TESBDR) rotator cuff (RC) repair technique has been developed to optimize healing biology at a repaired RC tendon insertion. It has been shown in the laboratory to improve pressurized contact area and mean foot print pressure when compared with a double row anchor technique. Pressure has been shown to influence healing between tendon and bone, and the tendon compression vector provided by the transosseous-equivalent suture bridges may enhance healing. The purpose was to prospectively evaluate the outcomes of arthroscopic TESBDR RC repair.

Methods: Single center prospective case series study. Sixty-nine patients were selected to undergo arthroscopic TESBDR RC repair and were included in the current study. Primary outcome measures included the Oxford Shoulder Score (OSS), the University of California, Los Angeles (UCLA) score, the Constant-Murley (CM) Score and Range of motion (ROM). Secondary outcome measures included a Visual Analogue Scale (VAS) for pain, another VAS for patient satisfaction from the operative procedure, EuroQoL 5-Dimensions Questionnaire (EQ-5D) for quality of life assessment.

Results: At 24 months post-operative, average OSS score was 44, average UCLA score was 31, average CM score was 88, average forward flexion was 145°, average internal rotation was 35°, average external rotation was 79°, average abduction was 150°, average EQ-5D score was 0.73, average VAS for pain was 2.3, and average VAS for patient satisfaction was 9.2.

Conclusion: Arthroscopic TESBDR RC repair is a procedure with good post-operative functional outcome and low re-tear rate based on a short term follow-up.

Primary stability of rotator cuff repair: can more suture materials yield more strength?

INTRODUCTION

It remains unclear if the increased biomechanical stability of the double-row repair is solely a result of the technique itself or due to the greater number of utilized materials. This study analyses the various rotator cuff (RC) repair interfaces and the influence of doubling the number of suture knots, stitch techniques and suture anchors on the primary stability of the RC reconstruction.

MATERIALS AND METHODS

Established cyclic testing protocols were used to test the primary stability of the knot interface with a Duncan loop and Roeder knot, the tendon-to-suture interface with a single-stitch and Mason-Allen-stitch and the anchor-to-bone interface with OPUS Magnum 2® and BioCorkscrew® anchors. After doubling the materials, the interfaces were tested again and compared to the yielded solitary values. The maximum failure loads (Fmax), clinical failure (CF), system displacement (SD) and modes of failure were recorded.

RESULTS

Doubling the amount of knots, stitches and suture anchors improved almost all interface parameters. For example, Fmax, CF and SD of the Roeder knot could be significantly improved from 142.5 N to 256.7 N, from 82.5 N to 155.0 N and from 0.45 mm to 0.20 mm, respectively. The Mason-Allen stitch's Fmax improved from 196.4 N to 324.9 N, and CF from 94.25 N to 139.8 N, with almost identical SD of 0.81 mm and 0.84 mm. Bio-Corkscrew® Fmax improved from 232.5 N to 317.5 N, CF from 182.5 N to 210 N, and SD from 0.85 mm to 0.64 mm.

CONCLUSION

Doubling the number of knots, stitches and suture anchors increases the primary stability of the various RC repair interfaces and may result in RC rerupture rate reduction. Furthermore, this study suggests that a suture anchor loaded with two or three sutures may yield the same primary stability as two or three suture anchors loaded with a single suture. This in vitro biomechanical study focuses solely on the rotator cuff interfaces at time zero; the biological healing process was therefore not analysed and requires further investigation.

CLINICAL RELEVANCE

Improved primary stability by increased number of suture materials may reduce rate of RC rerupture.

Arthroscopic single-row versus double-row technique for repairing rotator cuff tears: a systematic review and meta-analysis

OBJECTIVE

The purpose of this study was to systematically review published reports that compare the outcomes of single-row and double-row suture anchor fixation in arthroscopic rotator cuff repair.

METHODS

Combined data regarding relevant patient characteristics, rotator cuff pathology, surgical techniques, postoperative rehabilitation regimens, University of California at Los Angeles (UCLA) Scores, Constant scores, American Shoulder and Elbow Society (ASES) scores, tendon healing, incidence of recurrent rotator cuff defects, shoulder muscle strength, range of motion, surgical time and patient satisfaction were assessed.

RESULTS

Seven eligible randomized controlled studies and four prospective cohort studies were identified. There were no significant differences between the single-row and double-row groups in terms of Constant or ASES scores. However, UCLA scores, tendon healing, abduction shoulder strength index (SSI), external rotation SSI and internal rotation SSI were significantly better for double-row technique than for single-row technique. A statistically significant advantage for double-row repair according to UCLA score and external rotation SSI was found in the subgroup with tears greater than 3 cm.

CONCLUSION

No definite conclusion could be drawn about differences in overall outcomes of double- and single-row techniques for repairing for small to medium (<3 cm) or large to massive (>3 cm) rotator cuff tears, even though some measures of clinical outcome showed significant differences between these two techniques.

Factors affecting healing after arthroscopic rotator cuff repair

Rotator cuff repair has been shown to have good long-term results. Unfortunately, a significant proportion of repairs still fail to heal. Many factors, both patient and surgeon related, can influence healing after repair. Older age, larger tear size, worse muscle quality, greater muscle-tendon unit retraction, smoking, osteoporosis, diabetes and hypercholesterolemia have all shown to negatively influence tendon healing. Surgeon related factors that can influence healing include repair construct-single vs double row, rehabilitation, and biologics including platelet rich plasma and mesenchymal stem cells. Double-row repairs are biomechanically stronger and have better healing rates compared with single-row repairs although clinical outcomes are equivalent between both constructs. Slower, less aggressive rehabilitation programs have demonstrated improved healing with no negative effect on final range of motion and are therefore recommended after repair of most full thickness tears. Additionally no definitive evidence supports the use of platelet rich plasma or mesenchymal stem cells regarding improvement of healing rates and clinical outcomes. Further research is needed to identify effective biologically directed augmentations that will improve healing rates and clinical outcomes after rotator cuff repair.

Increasing pullout strength of suture anchors in osteoporotic bone using augmentation--a cadaver study

BACKGROUND

Rotator cuff tears are of increasing clinical impact in the physically active elderly patients. Recent research revealed, that a high percentage of these patients present with significant loss of bone mineral density at the insertion site of the rotator cuff, thereby compromising suture anchorage for operative repair. We therefore hypothesized that augmentation of suture anchors improves biomechanical properties in low bone quality.

METHODS

28 osteoporotic humeral heads were included in this biomechanical study. Bone quality at the anchor insertion sites (group 1: posterior-medial; group 2: anterior-lateral) within the greater tuberosity was analyzed using HR-pQCT (voxel size: 82μm). Anchor positions of identical quality were then randomized to either conventional screw anchorage or polymethylmethacrylat augmented screw anchorage. All anchors were cyclically ramp-loaded until pullout.

FINDINGS

Pullout strength accounted for 226N in group I for conventional anchorage and for 332N in augmented technique. In group 2 (anterior-lateral) the pullout strength was 209N (conventional) and 304N (augmented). Pull-out strength of augmented screw anchors was significantly higher in both groups (p<0.05).

INTERPRETATION

Compared to conventional insertion techniques, the cement augmentation technique increases the pullout strength of suture anchors in low bone quality significantly. Cement augmentation could therefore be a helpful tool for improved suture anchor stability, especially in locations of low bone quality.

Arthroscopic double-row cuff repair with suture-bridging: a structural and functional comparison of two techniques

PURPOSE

The aim of this study was to compare the functional and structural outcomes of 2 techniques for double-row, suture-bridging cuff repair.

METHODS

A consecutive series of 73 patients who underwent arthroscopic, double-row, suture-bridge primary rotator cuff repair of full-thickness supraspinatus tear were evaluated. Thirty-eight shoulders were repaired by the arthroscopic, tied, suture-bridging technique (group A), and 35 shoulders by knot-less bridging with suture tape material (group B). Constant scores, pain, range of motion, strength, and complications were measured after a minimum follow-up period of 12 months post-operatively. Structural integrity of the repairs was evaluated systematically by either magnetic resonance imaging or computed tomography arthrography.

RESULTS

Median follow-up after surgery was 29 (23-32) months in group A, and 21 (12-23) months in group B. Mean pain relief, range of motion, strength, and constant score improved significantly in both groups. No statistical differences were found between groups in the post-operative period. According to control imaging, the re-tear rate trended to be higher in group A (23.4 %) than in group B (17.1 %), although not significantly.

CONCLUSION

Both bridging repair techniques achieved successful functional outcomes. In terms of structural outcome, the knot-less tape-bridging construct showed a lower but not significant re-tear rate. Longer follow-up is needed to confirm these results and to evaluate potential differences between the two techniques.

LEVEL OF EVIDENCE

A prospective, non-randomized, comparative study, Level III.

A cruciate suture technique for rotator cuff repair

PURPOSE

Re-establishment of the native footprint during rotator cuff repair is important for maximizing healing potential and fixation strength. The purpose of this study was to evaluate the contact area, contact pressure, stiffness and tensile strength of a new single-row cruciate suture repair and to compare these results to those of the Mason-Allen, double-row and transosseous repairs.

METHODS

Infraspinatus tendons from fifty-six lamb shoulders were harvested and randomly assigned to cruciate suture, Mason-Allen, double-row and transosseous repair groups. Repairs were performed over pressure-sensitive film and footprint contact area and pressure measured. Repaired tendon specimens were also loaded in uniaxial tension, and ultimate tensile strength and stiffness measured.

RESULTS

The cruciate suture repair established significantly greater footprint contact area compared to the Mason-Allen repair (mean difference = 101 mm(2), p = 0.003). The ultimate tensile strength and stiffness of the double-row repair was significantly higher than that of all other repair groups (p < 0.05). The average footprint contact pressure of the cruciate suture repair (0.78 MPa) was similar to that of the Mason-Allen (0.74 MPa) and double-row repairs (0.79 MPa). The ultimate tensile strength of the cruciate suture repair was significantly greater than that of the transosseous repair (mean difference 62.4 N, p = 0.002).

CONCLUSION

The cruciate suture repair may improve strength and healing at the repaired tendon rotator cuff insertion relative to other single-row repair techniques. It may represent a faster, easier and more cost-effective alternative to double-row repairs.

Incidence of retear with double-row versus single-row rotator cuff repair

Rotator cuff tears have a high recurrence rate, even after arthroscopic rotator cuff repair. Although some biomechanical evidence suggests the superiority of the double-row vs the single-row technique, clinical findings regarding these methods have been controversial. The purpose of this study was to determine whether the double-row repair method results in a lower incidence of recurrent tearing compared with the single-row method. Electronic databases were systematically searched to identify reports of randomized, controlled trials (RCTs) comparing single-row with double-row rotator cuff repair. The primary outcome assessed was retear of the repaired cuff. Secondary outcome measures were the American Shoulder and Elbow Surgeons (ASES) shoulder score, the Constant shoulder score, and the University of California, Los Angeles (UCLA) score. Heterogeneity between the included studies was assessed. Six studies involving 428 patients were included in the review. Compared with single-row repair, double-row repair demonstrated a lower retear incidence (risk ratio [RR]=1.71 [95% confidence interval (CI), 1.18-2.49]; P=.005; I(2)=0%) and a reduced incidence of partial-thickness retears (RR=2.16 [95% CI, 1.26-3.71]; P=.005; I(2)=26%). Functional ASES, Constant, and UCLA scores showed no difference between single- and double-row cuff repairs. Use of the double-row technique decreased the incidence of retears, especially partial-thickness retears, compared with the single-row technique. The functional outcome was not significantly different between the 2 techniques. To improve the structural outcome of the repaired rotator cuff, surgeons should use the double-row technique. However, further long-term RCTs on this topic are needed.

Meta-analysis comparing single-row and double-row repair techniques in the arthroscopic treatment of rotator cuff tears

BACKGROUND

Rotator cuff tears are among the most common shoulder injuries and can be a source of persistent pain, disability, and decreased range of motion and strength. Our hypothesis was to conduct a meta-analysis of recently published studies to compare the clinical results of a double-row technique with the results of a single-row technique for different tear sizes.

METHODS

A search was performed in the MEDLINE, EMBASE, and Ovid databases. All randomized and quasi-randomized clinical trials that reported the outcome of single-row repair and double-row repair techniques were included in our meta-analysis. Two subgroups were set according to the tear size. The outcomes were the Constant score, American Shoulder and Elbow Surgeons (ASES) score, UCLA score, re-tear rate, range of motion, and muscle strength.

RESULTS

We included 9 studies in this meta-analysis, 5 of which were randomized prospective studies. There was a statistically significant difference in favor of double-row repair for the overall ASES score, re-tear rate, and internal rotation range of motion. In subgroup 2 (tear size > 30 mm in the anteroposterior dimension), double-row techniques produced better outcomes than single-row techniques. There were no statistically significant differences in the overall Constant score, UCLA score, external rotation and forward elevation range of motion, or muscle strength.

CONCLUSION

Double-row rotator cuff repair techniques have a significantly lower re-tear rate, higher ASES score, and greater range of motion of internal rotation compared with single-row repair techniques. Especially in those rotator cuff tears with a size >30 mm, the double-row technique is recommended for repair.

Rehabilitation following arthroscopic rotator cuff repair: a review of current literature

Physical rehabilitation following arthroscopic rotator cuff repair has conventionally involved a 4- to 6-week period of immobilization; there are two schools of thought regarding activity level during this period. Some authors encourage early, more aggressive rehabilitation along with the use of a continuous passive motion device; others propose later, more conservative rehabilitation. Although some studies report trends in improved early range of motion, pain relief, and outcomes scores with aggressive rehabilitation following rotator cuff repair, no definitive consensus exists supporting a clinical difference resulting from rehabilitation timing in the early stages of healing. Rehabilitation timing does not affect outcomes after 6 to 12 months postoperatively. Given the lack of information regarding which patient groups benefit from aggressive rehabilitation, individualized patient care is warranted.

An in-vitro study of rotator cuff tear and repair kinematics using single- and double-row suture anchor fixation

Purpose:

Double-row suture anchor fixation of the rotator cuff was developed to reduce repair failure rates. The purpose of this study was to determine the effects of simulated rotator cuff tears and subsequent repairs using single- and double-row suture anchor fixation on three-dimensional shoulder kinematics. It was hypothesized that both single- and double-row repairs would be effective in restoring active intact kinematics of the shoulder.

Materials and Methods:

Sixteen fresh-frozen cadaveric shoulder specimens (eight matched pairs) were tested using a custom loading apparatus designed to simulate unconstrained motion of the shoulder. In each specimen, the rotator cuff was sectioned to create a medium-sized (2 cm) tear. Within each pair, one specimen was randomized to a single-row suture anchor repair, while the contralateral side underwent a double-row suture anchor repair. Joint kinematics were recorded for intact, torn, and repaired scenarios using an electromagnetic tracking device.

Results:

Active kinematics confirmed that a medium-sized rotator cuff tear affected glenohumeral kinematics when compared to the intact state. Single- and double-row suture anchor repairs restored the kinematics of the intact specimen.

Conclusions:

This study illustrates the effects of medium-sized rotator cuff tears and their repairs on active glenohumeral kinematics. No significant difference (P ≥ 0.10) was found between the kinematics of single- and double-row techniques in medium-sized rotator cuff repairs.

Clinical Relevance:

Determining the relative effects of single- and double-row suture anchor repairs of the rotator cuff will allow physicians to be better equipped to treat patients with rotator cuff disease.

Rotator cuff tendon repair morphology comparing 2 single-anchor repair techniques

PURPOSE

To compare the effect of 2 common rotator cuff repair techniques, for smaller tears limited to the use of a single anchor, on tendon morphology in relation to the footprint.

METHODS

Six matched pairs of human shoulders were dissected, and a standardized 10-mm supraspinatus tendon tear was created. Two single-anchor repairs were performed: simple repair with the anchor on the footprint or inverted-mattress repair with the anchor 1 cm distal-lateral to the footprint. The repaired specimens were frozen in situ with liquid nitrogen. Coronal cross sections through the intact and repaired tendon were made. A digitizer was used to measure variables including tendon area and radius of tendon curvature.

RESULTS

Comparing between repairs, we found significantly more gap formation for the simple repair at the repair cross section (3.67 ± 0.32 mm v 0.68 ± 0.10 mm, P = .00050). The simple repair had less tendon area (38.28 ± 2.50 mm(2)v 58.65 ± 4.06 mm(2), P = .0036) and a smaller radius of curvature (8.47 ± 1.39 mm v 32.51 ± 3.94 mm, P = .0046). For the simple repair, there was significantly more gap formation, less tendon area, and a smaller radius of tendon curvature for all repair cross sections compared with the intact cross sections (P < .05). For the inverted-mattress repair, there was more gap formation compared with the intact condition (P < .05), although it was less than 1 mm on average; for tendon area, radius of curvature, and tendon height, the cross section centered on the repair showed no differences compared with the intact control.

CONCLUSIONS

For rotator cuff tears that are 10 mm or smaller and limited to the use of a single anchor, using a distal-lateral anchor position with tape-type suture can provide better maintenance of native tendon morphology and footprint dimensions when compared with repair that uses standard sutures and places the anchor on the footprint.

CLINICAL RELEVANCE

For smaller tears, the inverted-mattress repair described in this article may provide a relatively improved healing environment compared with a simple repair on the footprint, potentially optimizing the prevention of early tear progression.

Current biomechanical concepts for rotator cuff repair

For the past few decades, the repair of rotator cuff tears has evolved significantly with advances in arthroscopy techniques, suture anchors and instrumentation. From the biomechanical perspective, the focus in arthroscopic repair has been on increasing fixation strength and restoration of the footprint contact characteristics to provide early rehabilitation and improve healing. To accomplish these objectives, various repair strategies and construct configurations have been developed for rotator cuff repair with the understanding that many factors contribute to the structural integrity of the repaired construct. These include repaired rotator cuff tendon-footprint motion, increased tendon-footprint contact area and pressure, and tissue quality of tendon and bone. In addition, the healing response may be compromised by intrinsic factors such as decreased vascularity, hypoxia, and fibrocartilaginous changes or aforementioned extrinsic compression factors. Furthermore, it is well documented that torn rotator cuff muscles have a tendency to atrophy and become subject to fatty infiltration which may affect the longevity of the repair. Despite all the aforementioned factors, initial fixation strength is an essential consideration in optimizing rotator cuff repair. Therefore, numerous biomechanical studies have focused on elucidating the strongest devices, knots, and repair configurations to improve contact characteristics for rotator cuff repair. In this review, the biomechanical concepts behind current rotator cuff repair techniques will be reviewed and discussed.