Rotator Cuff Matrix Augmentation and Interposition: A Systematic Review and Meta-analysis

3-Dimensional Bioprinting of a Tendon Stem Cell-Derived Exosomes Loaded Scaffold to Bridge the Unrepairable Massive Rotator Cuff Tear

BACKGROUND

Unrepairable massive rotator cuff tears (UMRCTs) are challenging to surgeons owing to the severely retracted rotator cuff musculotendinous tissues and extreme defects in the rotator cuff tendinous tissues.

PURPOSE

To fabricate a tendon stem cell-derived exosomes loaded scaffold (TSC-Exos-S) and investigate its effects on cellular bioactivity in vitro and repair in a rabbit UMRCT model in vivo.

STUDY DESIGN

Controlled laboratory study.

METHODS

TSC-Exos-S was fabricated by loading TSC-Exos and type 1 collagen (COL-I) into a 3-dimensional bioprinted and polycaprolactone (PCL)-based scaffold. The proliferation, migration, and tenogenic differentiation activities of rabbit bone marrow stem cells (BMSCs) were evaluated in vitro by culturing them in saline, PCL-based scaffold (S), COL-I loaded scaffold (COL-I-S), and TSC-Exos-S. In vivo studies were conducted on a rabbit UMRCT model, where bridging was repaired with S, COL-I-S, TSC-Exos-S, and autologous fascia lata (FL). Histological and biomechanical analyses were performed at 8 and 16 weeks postoperatively.

RESULTS

TSC-Exos-S exhibited reliable mechanical strength and subcutaneous degradation, which did not occur before tissue regeneration. TSC-Exos-S significantly promoted the proliferation, migration, and tenogenic differentiation of rabbit BMSCs in vitro. In vivo studies showed that UMRCT repaired with TSC-Exos-S exhibited significant signs of tendinous tissue regeneration at the bridging site with regard to specific collagen staining. Moreover, no significant differences were observed in the histological and biomechanical properties compared with those repaired with autologous FL.

CONCLUSION

TSC-Exos-S achieved tendinous tissue regeneration in UMRCT by providing mechanical support and promoting the trend toward tenogenic differentiation.

CLINICAL RELEVANCE

The present study proposes a potential strategy for repairing UMRCT with severely retracted musculotendinous tissues and large tendinous tissue defects.

Surgical Treatment and Outcomes for Gluteal Tendon Tears

PURPOSE OF REVIEW

Gluteus medius and minimus tears, or hip abductor tendon tears, are increasingly identified as a source of lateral hip pain. Once underappreciated and undertreated, they are now recognized as a cause of greater trochanteric pain syndrome and a pathology amenable to both nonoperative and operative modalities. This review summarizes relevant anatomy, clinical presentation, and treatment options for gluteus medius tears, focusing on surgical options.

RECENT FINDINGS

When surgical intervention is indicated, repair, reconstruction, or tendon transfer may be considered. Open and endoscopic repair techniques demonstrate similar outcomes with improvements in patient-reported outcomes and low complication and retear rates for both partial and full thickness tears. Variations in fixation construct and graft augmentations have been described, though clinical evidence remains limited to support specific techniques. Gluteus maximus transfer via open approach is a salvage option for the severely atrophied, retracted, or revision gluteus tendon; however, persistent limitations in abduction strength and gait abnormalities are common. Emerging evidence continues to evolve our understanding of surgical decision-making for gluteus tendon tears. The current literature supports either open or endoscopic repair techniques and open tendon transfer as a salvAage option. Further study is needed to determine the optimal fixation construct, the role of graft augmentation, and patient-related factors that influence postoperative outcomes.

Rotator Cuff Repair With Patch Augmentation Is Associated With Lower Retear Rates for Large Tears: A Systematic Review of Randomized Controlled Trials

PURPOSE

To perform a systematic review of randomized controlled trials comparing clinical outcomes of rotator cuff repair with and without patch augmentation.

METHODS

A systematic review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines by searching PubMed, the Cochrane Library, and Embase to identify randomized controlled trials that directly compared outcomes between rotator cuff repair (RCR) with versus without patch augmentation. Patients were evaluated based on retear rate, histological outcomes, radiological outcomes, and patient-reported outcomes (Constant score; American Shoulder and Elbow Surgeons [ASES] score; University of California-Los Angeles shoulder scale; Simple Shoulder Test; EuroQol-visual analog scale; Disabilities of the Arm, Shoulder and Hand score; and PENN shoulder score questionnaire).

RESULTS

Six studies (1 level I, 5 level II) met inclusion criteria, including 188 patients undergoing RCR alone (Control) and 193 patients undergoing RCR with patch augmentation (Patch). Patient age ranged from 56.0 to 68.0 years. The mean follow-up time ranged from 14.0 to 68.4 months. The average body mass index ranged from 24.4 to 29.4, and the overall percentage of males ranged from 32.5% to 82.3%. Three studies found significantly decreased retear rates with patch augmentation. The retear rate ranged from 34.0% to 65.4% in the Control group and 9.1% to 52.9% in the Patch group. One study found a significant difference for the Constant score favoring the Patch group. Two studies found a significant difference for the ASES score favoring the Patch group. One study found significantly better results with patch augmentation in terms of repaired tendon thickness and footprint coverage, based on magnetic resonance imaging.

CONCLUSIONS

Patch augmentation of rotator cuff repairs may be associated with lower retear rates for large tears. There is limited evidence to suggest that patch augmentation is associated with improved patient-reported outcomes.

LEVEL OF EVIDENCE

Level II, systematic review of level I and II studies.

Dermal Allograft Augmentation for Large and Massive Rotator Cuff Tears and Revisions: A Case Series

Introduction Arthroscopic advancements have notably improved rotator cuff repair, yet the healing of tendons and retear risks still pose significant challenges, especially with massive and large tears. These larger tears have shown a quadruple increase in retear rate when the tear size grows from 1-3 cm. The prevalent cause of failure, particularly in tears with fatty degeneration, is suture tearing. As such, techniques that enhance tendon healing are pivotal due to their correlation with improved functional outcomes. Dermal allograft augmentation (DAA) is one method that has demonstrated improvements in rotator cuff repair biomechanics, as well as the promotion of vascularization and neotendon formation. This study evaluates the efficacy of DAA in the postoperative healing of large and massive rotator cuff tears, assessed through patient-reported outcomes and functional range of motion. Methods This retrospective study reviewed a single surgeon's database, selecting patients who underwent arthroscopic surgery for full-thickness rotator cuff tears measuring at least 3 cm, or those with maximum stage II fatty infiltration of the supraspinatus or infraspinatus muscle on MRI. We used three validated patient-reported outcome (PRO) measures, American Shoulder and Elbow Surgeon Score (ASES), Single Assessment Numeric Evaluation (SANE), and Simple Shoulder Test (SST), alongside a range of motion metrics, external rotation (ER), and forward flexion (FF). These were recorded pre-operatively and, at minimum, one year post-operatively, with a standard student t-test employed for comparative analysis. Results Out of 18 total patients, the average age was 61 years, and 83% were male. The cause of injury was mostly traumatic in nature (n=11), with the remainder being chronic (n=7). All three PROs (n=11) demonstrated a statistically significant increase in score including ASES (p=0.003), SANE (p=0.004), and SST (p=0.039). External rotation also significantly improved pre- to post-operative function (46 vs 58, p=0.049). Three patients (17%) suffered from a retear within three months of their rotator cuff repair. Two patients (11%) required a reverse shoulder arthroplasty within a year. Conclusion Our study demonstrated that DAA in rotator cuff repair yielded notable functional and clinical advancements, with a moderately low retear rate as confirmed by ultrasound. These outcomes suggest that DAA is a promising intervention for large and historically difficult rotator cuff tears, offering significant implications for future treatment protocols.

Acellular Collagen Matrix Patch Augmentation of Arthroscopic Rotator Cuff Repair Reduces Re-Tear Rates: A Meta-analysis of Randomized Control Trials

PURPOSE

To perform a meta-analysis of randomized controlled trials (RCTs) to compare the outcomes of arthroscopic rotator cuff repair (ARCR) with and without acellular collagen matrix patch (ACMP) augmentation.

METHODS

A literature search of 3 databases was performed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RCTs comparing ACMP augmentation and a control for ARCR were included. Clinical outcomes were compared using Revman, and a P value < .05 was considered to be statistically significant.

RESULTS

Five RCTs with 307 patients were included. Overall, 11% of patients treated with ACMP augmentation and 34% of patients in the control group had a re-tear (P = .0006). The mean Constant score was 90.1 with ACMP augmentation, and 87.3 in controls (P = .02). Additionally, there was a significant higher American Shoulder and Elbow Surgeons score with ACMP augmentation (87.7 vs 82.1, P = .01).

CONCLUSIONS

The RCTs in the literature support the use of ACMP augment as a modality to reduce re-tear rates and improve outcomes after ARCR.

LEVEL OF EVIDENCE

Level II, Meta-Analysis of Level II Studies meta-analysis of Level II studies.

Mini-Open Fascia Lata Interposition Graft Results In Superior 2-Year Clinical Outcomes When Compared to Arthroscopic Partial Repair for Irreparable Rotator Cuff Tear: A Single-Blind Randomized Controlled Trial

PURPOSE

To evaluate and compare the results of surgical treatment for irreparable rotator cuff tear (IRCT) by the mini-open interposition procedure using fascia lata autograft against outcomes of the arthroscopic partial repair technique.

METHODS

An interventional, prospective, controlled, randomized, single-blinded study involving 2 study groups was conducted. The graft group (n = 20) underwent the mini-open interposition procedure using fascia lata autograft. The control group (n = 22) underwent arthroscopic partial repair. Patients were evaluated using the University of California Los Angeles (UCLA) Shoulder scale, the American Shoulder and Elbow Surgeons (ASES) score, the Constant-Murley (Constant) score, the visual analogue scale (VAS) pain score, active range of motion, frontal flexion strength, retear rates evaluated by magnetic resonance imaging analysis, occurrence of complications, and the minimal clinically important difference (MCID).

RESULTS

The graft group had better UCLA (31.5 vs 28.18, P = .035) (100% exceeded the MCID for the graft group and 95% for the control group), ASES (88.62 vs 77.06, P = .016) (100% exceeded the MCID for both groups), Constant (78.85 vs 61.68, P < .001), and VAS (0.95 vs 2.59, P = .01) scores at the 24-month follow-up. For active forward elevation range, both groups showed no statistically significant differences (168.5 vs 164.54, P = .538). The results for active external and internal rotation were better in the graft group (60.25 vs 40, and 9.1 vs 6.9, P < .001), as was frontal flexion strength (4.24 vs 2.67, P = .005). The graft group also had lower retear rates (15% vs 45.5%, P = .033). No complications were reported.

CONCLUSIONS

Outcomes of surgeries for IRCT by the mini-open interposition procedure using fascia lata autograft and by the arthroscopic partial repair technique showed good results in both groups over time and exceeded the MCID. However, most comparative outcomes between groups showed better results for the interposition procedure.

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

No Difference In Clinical Outcomes Following Repair of Large Retracted Anterior Rotator Cuff Tears Using Patch Augmentation With Human Dermal Allograft Versus Anterior Cable Reconstruction With Biceps Tendon Autograft

PURPOSE

To compare the clinical outcomes and tendon integrity after rotator cuff repair combined with anterior cable reconstruction (ACR) using the proximal biceps tendon and patch augmentation (PA) using a human dermal allograft (HDA) in a large retracted anterior rotator cuff tear.

METHODS

Patients who underwent arthroscopic rotator cuff repair with 2 different augmentation procedures between January 2017 and December 2020 were enrolled. The inclusion criteria were patients who were treated by arthroscopic rotator cuff repair with ACR using the proximal biceps tendon (ACR group) or patch augmentation using a an HDA (PA group) and follow-up for at least 2 years. Clinical outcomes were assessed using American Shoulder and Elbow Surgeons (ASES) score, Constant score, and the number of patients who achieved minimal clinically important differences (MCID). Magnetic resonance imaging was performed to evaluate tendon integrity after surgery.

RESULTS

A total of 92 patients were enrolled (ACR group = 55 patients and PA group = 37 patients). The mean ASES and Constant scores significantly improved in the ACR group (68.8 ± 15.3 and 58.4 ± 16.9 before surgery vs 91.4 ± 6.3 and 87.8 ± 6.0 after surgery, P < .001) and in the PA group (63.7 ± 16.7 and 57.9 ± 15.4 before surgery vs 93.1 ± 6.3 and 88.3 ± 6.2 after surgery, P < .001). Overall, 78 patients (84.8%) achieved the MCID with 81.8% in the ACR group and 89.2% in the PA group, with no significant differences between the 2 groups (P = .638). Ten patients (18.2%) had retear in the ACR group, and three patients (8.1%) had retear in the PA group (P = .174).

CONCLUSIONS

In large retracted anterior rotator cuff tears, both augmentation techniques using biceps tendon autograft and HDA provided satisfactory clinical outcomes that achieved the MCID in 84.8%, range of motion restoration, and lower retear rates with no significant differences between the two groups.

LEVEL OF EVIDENCE

Level III, retrospective case-control study.

Augmentation of Rotator Cuff Repair Using Umbilical Cord Graft: A Preliminary Observational Study

Due to the high rate of rotator cuff re-tear there is an extensive research on augmentation of rotator cuff repairs. The purpose of this single center, prospective study was to evaluate the results of augmentation of the rotator cuff repair with an umbilical cord allograft. The graft group in which the rotator cuff repair was augmented with the graft as an on-lay patch was consisted of 14 patients, while the control group was consisted of 10 patients. The primary outcome of the study was incidence of rotator cuff retears, while secondary outcomes included functional and pain scores. At 6 mo there was a significantly higher incidence of retears in the control group (30%) compared to the graft group (0%; P = 0.028), while at 12 mo the retear rates were statistically similar for the two groups (P = 0.46). The Constant-Murley scores, the ASES scores and the VAS score were similar (P > 0.05) for the two groups at all study times. The results of the study indicated that augmentation of the cuff repair with human umbilical cord graft can result in similar patient reported outcomes compared to a cuff repair without augmentation, but with a lower re-tear rate at 6 mo.

MESENCHYMAL CELLS IN ROTATOR CUFF REPAIR - TECHNIQUE DESCRIPTION AND CASE REPORTS

Objective

To describe a protocol of obtention of mesenchymal stem cells and to report their use as a biological adjuvant in three patients undergoing arthroscopic rotator cuff repair.

Methods

Case series of patients who underwent arthroscopic repair of isolated full-thickness supraspinatus tear using mesenchymal stem cells obtained from the bone marrow as a biological adjuvant. All patients were operated on at the same institution, by a surgeon with 13 years of experience. The cells were applied at the end of the procedure, at the tendon-bone interface, at an approximate concentration of 2,000,000 mesenchymal cells/mm3 and a total volume of 5 ml.

Results

All patients improved with the procedure, with one excellent and two good results. All cases overcame the minimally important clinical difference. All cases reached tendon healing, without partial or complete re-tears. We observed no complications.

Conclusion

Arthroscopic rotator cuff repair with added mesenchymal cells obtained from bone marrow and submitted to a cell expansion process led to good functional results and healing in all cases in the sample, with no complications. Level of Evidence IV, Case Series.

Tendon-derived matrix crosslinking techniques for electrospun multi-layered scaffolds

Tendon tears are common and healing often occurs incompletely and by fibrosis. Tissue engineering seeks to improve repair, and one approach under investigation uses cell-seeded scaffolds containing biomimetic factors. Retention of biomimetic factors on the scaffolds is likely critical to maximize their benefit, while minimizing the risk of adverse effects, and without losing the beneficial effects of the biomimetic factors. The aim of the current study was to evaluate cross-linking methods to enhance the retention of tendon-derived matrix (TDM) on electrospun poly(ε-caprolactone) (PCL) scaffolds. We tested the effects of ultraviolet (UV) or carbodiimide (EDC:NHS:COOH) crosslinking methods to better retain TDM to the scaffolds and stimulate tendon-like matrix synthesis. Initially, we tested various crosslinking configurations of carbodiimide (2.5:1:1, 5:2:1, and 10:4:1 EDC:NHS:COOH ratios) and UV (30 s 1 J/cm2 , 60 s 1 J/cm2 , and 60 s 4 J/cm2 ) on PCL films compared to un-crosslinked TDM. We found that no crosslinking tested retained more TDM than coating alone (Kruskal-Wallis: p > .05), but that human adipose stem cells (hASCs) spread most on the 60 s 1 J/cm2 UV- and 2.5:1:1 EDC-crosslinked films (Kruskal-Wallis: p < .05). Next, we compared the effects of 60 s 1 J/cm2 UV- and 2.5:1:1 EDC-crosslinked to TDM-coated and untreated PCL scaffolds on hASC-induced tendon-like differentiation. UV-crosslinked scaffolds had greater modulus and stiffness than PCL or TDM scaffolds, and hASCs spread more on UV-crosslinked scaffolds (ANOVA: p < .05). Fourier transform infrared spectra revealed that UV- or EDC-crosslinking TDM did not affect the peaks at wavenumbers characteristic of tendon. Crosslinking TDM to electrospun scaffolds improves tendon-like matrix synthesis, providing a viable strategy for improving retention of TDM on electrospun PCL scaffolds.

Rotator Cuff Augmentation: Its Role and Best Practices

Rotator cuff tears are a common source of pain and impairment in the shoulder. Healing of the rotator cuff tendons following repair has been associated with improved patient outcomes. While there have been many technical improvements in surgical techniques for rotator cuff repair, failure rates are still surprisingly high. Augmentation of these repairs has been shown to help with fixation biomechanics as well as healing rates. The described types of augments include autograft, allograft, xenograft, and synthetic options. This report reviews the commonly available types of augments and some of the outcomes associated with their use.

Radiologic and clinical outcomes of an arthroscopic bridging graft for irreparable rotator cuff tears with a modified MasonAllen stitch using a plantaris tendon autograft: a case series with minimum 2-year outcomes

BACKGROUND

Surgical management of a massive rotator cuff tear (RCT) is always challenging. This study describes the clinical and radiological outcomes of patients who underwent bridging grafts using a plantaris tendon for an irreparable RCT.

METHODS

Thirteen patients with a massive RCT were treated with arthroscopic interposition of a folded plantaris tendon autograft between June 2017 and January 2020. For clinical evaluation, a visual analog scale (VAS), American Shoulder and Elbow Surgeons (ASES) score, Disabilities of the Arm, Shoulder, and Hand (DASH) score, Constant-Murley score, and range of motion values were collected. For radiographic evaluation, standardized magnetic resonance imaging and ultrasonography were performed to check the integrity of the interposed tendon.

RESULTS

A statistically significant improvement at the final follow-up was evident in scores for the VAS (-3.0, P=0.003), ASES (24.9, P=0.002), D ASH (-20.6, P=0.001), and Constant-Murley values (14.2, P=0.010). In addition, significant improvement was shown in postoperative flexion (17.3°, P=0.026) and external rotation (27.7°, P<0.001). In postoperative radiologic evaluations, the interposed tendons were intact at the last examination in 12 of the 13 patients. No complications related to donor sites were reported.

CONCLUSIONS

An arthroscopic bridging graft for irreparable RCTs using a modified Mason-Allen stitch and a plantaris autograft resulted in improved short-term radiological and clinical outcomes. Graft integrity was maintained for up to 2 years in most patients. Level of evidence: IV.

Extreme Medialized Repair for Challenging Large and Massive Rotator Cuff Tears Reveals Healing and Significant Functional Improvement

PURPOSE

To evaluate range of motion, muscle strength, clinical outcomes, and radiographic results of the extreme medialized procedure on rotator cuff tears that were initially irreparable.

METHODS

From arthroscopic rotator cuff repair cases performed at our institution (June 2017 and August 2020), we retrospectively reviewed cases in which the rotator cuff was (1) unable to be withdrawn to the greater tuberosity, (2) repaired using the extreme medialized procedure, and (3) followed up for a minimum of 2 years. Patients with a history of previous surgery were excluded. Preoperative and postoperative scores were used for clinical evaluation. Imaging evaluation used 2-year postoperative magnetic resonance (MR) images.

RESULTS

Sixty-four patients met the criteria; mean age 68.2 ± 7.9 (range 51-82) years; mean follow-up period 26 ± 2 (24-37) months. Tear size: 45 ± 7.1 (30-70) mm in medial to lateral diameters, 40 ± 9.3 (30-60) mm in anteroposterior diameter; suture anchor number: 5.5 ± 1.2 (4-8). The visual analog scale score (50.7 to 11.8), the University of California, Los Angeles, score (12 to 31), constant score (45 to 31), and the American Shoulder and Elbow Surgeons score (53 to 31) at the final follow-up improved compared with preoperative values (all P < .0001). Preoperative and postoperative changes in range of motion also showed improvement in anterior elevation (107° to 151°, P < .0001), abduction (100° to 154°, P < .0001), external rotation (41° to 47°, P = .0238), and internal rotation (L1 to Th10, P < .0001). Muscle strength was also improved in abduction (from 1.9 kg to 5.0 kg, P < .0001) and external rotation (from 3.5 kg to 7.7 kg, P < .0001). MR imaging evaluation revealed 2 cases (3.1%) of retears that fell into type 4 Sugaya classification.

CONCLUSIONS

Extremely medialized repair of large and massive tears not able to be repaired using conventional techniques led to improved clinical outcomes compared to preoperative conditions.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Graft Augmentation of Rotator Cuff Repair Improves Load to Failure But Does Not Affect Stiffness or Gap Formation: A Meta-analysis of Biomechanical Studies

PURPOSE

To examine the biomechanical properties of rotator cuff repair with graft augmentation (RCR-G) with regard to ultimate load to failure, gap displacement, and stiffness.

METHODS

A systematic review was performed by searching PubMed, the Cochrane library, and Embase using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify studies that analyzed the biomechanical properties of RCR-G. The search string implemented used the concepts "rotator cuff" and "graft," and "biomechanical" OR "cadaver." Meta-analysis was performed to provide a quantitative comparison of the 2 techniques. Primary outcome measures were ultimate load to failure (N), gap displacement (mm), and stiffness (N/mm).

RESULTS

Our initial search yielded 1,493 articles for review. Following screening for inclusion criteria, 8 studies were included in the meta-analysis, including a total of 191 cadaveric specimens (106 RCR-G, 85 RCR). The pooled analysis from 6 studies reporting on ultimate load to failure revealed a statistically significant difference in favor of RCR-G compared with RCR (P < .001). Pooled analysis from 6 studies reporting on gap displacement failed to reveal a difference between RCR-G and RCR (P = .719). Pooled analysis from 4 studies reporting on stiffness failed to reveal a difference between RCR-G and RCR (P = .842).

CONCLUSIONS

Graft augmentation of RCR in vitro resulted in significantly increased ultimate load to failure, with no influence on gap formation or stiffness.

CLINICAL RELEVANCE

The biomechanical advantage of RCR with graft augmentation demonstrated via increased ultimate load to failure in cadaveric studies may provide an explanation for the decreased RCR retear rates and improved patient reported outcomes reported in the clinical literature regarding graft augmentation.

Biphasic Interpositional Allograft for Rotator Cuff Repair Augmentation Is Safe in an Ovine Model

PURPOSE

To perform a preclinical histologic assessment of a biphasic acellular interpositional cancellous allograft in an ovine model of rotator cuff repair (RCR) designed to better understand its safety profile and effects on tendon healing after RCR.

METHODS

Thirty skeletally mature sheep with clinically normal shoulders with an artificially created degenerative infraspinatus tendon tear were randomized to control and treatment groups. Animals were euthanized at 3 weeks, 6 weeks, and 12 weeks. After gross dissection, rotator cuff specimens were fixed with formalin and polymerized for sectioning and staining. Blinded histologic scores evaluated inflammatory cell infiltrates, signs of degradation, particulate debris, collagen arrangement, neovascularization, and enthesis qualitative measures.

RESULTS

There were no treatment specimens that exhibited histologic signs of a significant infection, inflammatory infiltrate, or foreign body reaction such as granuloma or fibrous capsule formation. Histologic scores in all categories were not significantly different at all time points, including the primary end point mean cumulative inflammatory score (control: 3.66 ± 1.21 vs treated: 4.33 ± 1.51, P = .42), when comparing the treatment and control RCR groups. In general, the degree of tendon healing and host tissue response was essentially equivalent between the 2 groups with observation of low overall levels of inflammation and progressive improvements in collagen organization, reduced tenocyte activity, and fibrocartilaginous enthesis reformation.

CONCLUSIONS

This histologic study demonstrated the use of a biphasic interpositional allograft for RCR augmentation in an ovine model does not generate an inflammatory response or foreign body reaction. Use of the biphasic interpositional allograft resulted in a histological profile that was essentially equivalent to that of a standard RCR at 3-, 6-, and 12-week postoperative timepoints. These findings suggest that a biphasic interpositional allograft is safe for further clinical investigation in humans before broader clinical application.

CLINICAL RELEVANCE

Patch augmentation of RCR is a popular technique that has shown clinical success in improving the likelihood of a successful repair in patients at elevated risk for retear. Newer augmentation technologies are being developed to address the biology at the interface between the bone and soft tissue where failure typically occurs.

The statistical fragility of studies on rotator cuff repair with graft augmentation

BACKGROUND

Clinical decision-making often relies on evidence-based medicine. Our purpose was to determine the fragility index (FI) and fragility quotient (FQ) for studies evaluating rotator cuff repair (RCR) with graft augmentation. A lost to follow-up (LTF) value greater than the FI indicates statistical instability for the reported outcomes and conclusions.

METHODS

We performed a systematic review using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines by searching PubMed, the Cochrane library, and Embase in June 2022 to identify studies of RCR with graft augmentation. Comparative studies with at least 1 statistically analyzed dichotomous outcome were included. Seventeen studies published in seven peer-reviewed journals from 2003 to 2019 were subsequently evaluated. The FI was determined by changing each reported outcome event within 2 × 2 contingency tables until statistical significance or nonsignificance was reversed. The associated FQ was determined by dividing the FI by the sample size. LTF values were also extracted from each included study.

RESULTS

The included studies had a total of 1098 patients with 36 dichotomous outcomes. The associated median FI was 4 (interquartile range 2-5), indicating that the reversal of 4 patients' outcomes would have reversed the finding of significant difference. The median FQ was 0.08 (interquartile range 0.04-0.15), indicating that in a sample of 100 patients, reversal of 8 patients' outcomes would reverse statistical significance. The median number of patients LTF was 3 (range 0-25), with 56% of reported outcomes having LTF greater than their respective FI.

CONCLUSION

Studies of RCR with graft augmentation lack statistical stability, with few altered outcome events required to reverse statistical significance. Larger comparative studies with better follow-up will strengthen the statistical stability of the evidence for RCR with graft augmentation. For future investigations and reports, we recommend including FI and FQ along with traditional statistical significance analyses to provide better context on the strength of conclusions.

Development of a full-thickness acellular dermal graft from human skin: Case report of first patient rotator cuff patch augmentation repair

The processing and initial testing of a new human tissue preparation is described. Full-thickness Acellular Dermal Matrix (ftADM) is the extracellular matrix (ECM) obtained by decellularization of full-thickness human skin from cadaveric donors. The safety, stability and usability of the graft are discussed with respect to the results of the residual cellular content, maintenance of ECM components, and biomechanical properties. Quantitative and qualitative analysis of the ECM demonstrated the absence of cell debris, while the native structure of human dermis was maintained. Biomechanical testing showed stiffness values comparable to other commercial products used for tendon reinforcement, suggesting that our ftADM could be successfully used not only in soft tissue regeneration surgeries, but also in tendon reinforcement. First case of ftADM in rotator cuff augmentation is described. Technical management of the patch during surgery and clinical outcomes are discussed.

A Knitted PET Patch Enhances the Maturation of Regenerated Tendons in Bridging Reconstruction of Massive Rotator Cuff Tears in a Rabbit Model

BACKGROUND

Although nondegradable synthetic grafts for bridging reconstruction of massive rotator cuff tears (MRCTs) have shown satisfactory clinical outcomes, their function and details on graft-tendon healing and enthesis regeneration have not been fully studied.

HYPOTHESIS

The knitted polyethylene terephthalate (PET) patch as a nondegradable synthetic graft could provide sustained mechanical support, facilitating enthesis and tendon regeneration in the treatment of MRCTs.

STUDY DESIGN

Controlled laboratory study.

METHODS

A knitted PET patch was fabricated for bridging reconstruction (PET group) in a New Zealand White rabbit model of MRCTs (negative control group), and an autologous Achilles tendon was used as a control (autograft group). The animals were sacrificed, and tissue samples were harvested for gross observation as well as histological and biomechanical analyses at 4, 8, and 12 weeks postoperatively.

RESULTS

Histological analysis showed no significant difference in the graft-bone interface score between the PET and autograft groups at 4, 8, and 12 weeks postoperatively. Interestingly, in the PET group, Sharpey-like fibers were observed at 8 weeks, while fibrocartilage formation and the ingrowth of chondrocytes were recognized at 12 weeks. Meanwhile, the tendon maturing score was significantly higher in the PET group than in the autograft group (19.7 ± 1.5 vs 15.3 ± 1.2, respectively; P = .008) at 12 weeks, with parallel-oriented collagen fibers around the knitted PET patch. Moreover, the ultimate failure load of the PET group was similar to that of a healthy rabbit tendon at 8 weeks (125.6 ± 13.6 vs 130.8 ± 28.6 N, respectively; P > .05) and no different from that of the autograft group at 4, 8, and 12 weeks.

CONCLUSION

The knitted PET patch could not only immediately reconstruct the mechanical support for the torn tendon postoperatively in the rabbit model of MRCTs but also enhanced maturation of the regenerated tendon by fibrocartilage formation and improved the organization of collagen fibers. Herein, the knitted PET patch could be a promising candidate graft adopted in bridging reconstruction of MRCTs.

CLINICAL RELEVANCE

A nondegradable knitted PET patch can safely bridge MRCTs with satisfactory mechanical strength and the promotion of tissue regeneration.

Automated Assessment of Cell Infiltration and Removal in Decellularized Scaffolds - Experimental Study in Rabbits

Objective  Semiquantitative and automated measurement of nuclear material removal and cell infiltration in decellularized tendon scaffolds (DTSs). Method  16 pure New Zealand rabbits were used, and the gastrocnemius muscle tendon was collected bilaterally from half of these animals (16 tendons collected); 4 were kept as control and 12 were submitted to the decellularization protocol (DTS). Eight of the DTSs were used as an in vivo implant in the experimental rotator cuff tear (RCT) model, and the rest, as well as the controls, were used in the semiquantitative and automated evaluation of nuclear material removal. The eight additional rabbits were used to make the experimental model of RCT and subsequent evaluation of cellular infiltration after 2 or 8 weeks, within the DTS. Results  The semiquantitative and automated analysis used demonstrated a removal of 79% of nuclear material ( p  < 0.001 and power > 99%) and a decrease of 88% (p < 0.001 and power >99%) in the area occupied by nuclear material after the decellularization protocol. On cell infiltration in DTS, an increase of 256% (p < 0.001 and power >99%) in the number of cells within the DTS was observed in the comparison between 2 and 8 weeks postoperatively. Conclusion  The proposed semiquantitative and automated measurement method was able to objectively measure the removal of nuclear material and cell infiltration in DTS.

Double-Row Rotator Cuff Repair Technique With Dermal Allograft Augmentation

Rotator cuff tears are common and debilitating injuries in the orthopaedic patient population. Although arthroscopic repair of the rotator cuff generally leads to satisfactory outcomes, some tears would benefit from augmentation with allograft to supplement the native tissue. This biological augmentation has been shown to decrease retear rates and can be beneficial in certain cases based on the size of the tear, amount of retraction, age of the patient, and chronicity. In this technical note, we describe a simple and effective technique for arthroscopic rotator cuff repair with biological augmentation.

Human Dermal Allograft Patch Augmentation of Degenerate Rotator Cuff Tendon Using a Single Lateral-Row Technique

The role of biological augmentation in arthroscopic rotator cuff repair surgery has increased over the years. It has shown favorable healing rates and functional outcomes. Patch augmentation is commonly applied in repairs of massively retracted cuff tears, full-thickness tears, revision repair, or open cuff surgery. There is a paucity of literature on the use of patch augmentation when dealing with a chronic degenerate tendon associated with small-sized cuff tears. In recent years, the resorbable bioinductive bovine collagen implant has gained popularity for its application in partial-thickness tears via an isolated bioinductive repair fashion, without traditional rotator cuff repair. These bioinductive implants, albeit promising in their biological properties for tendon repair, lack structural strength and do not confer similar biomechanical advantages as human dermal allograft. We share our surgical technique for an arthroscopic patch augmentation involving human dermal allograft, using a single-lateral row surgical fixation, to address a degenerate cuff tendon with small-sized rotator cuff tear. We believe that our use of a human dermal patch augmentation conferred increased biomechanical advantage and reduced costs while delivering favorable outcomes for patients in our value-driven care.

Decellularized Bovine Pericardial Patch Loaded With Mesenchymal Stromal Cells Enhance the Mechanical Strength and Biological Healing of Large-to-Massive Rotator Cuff Tear in a Rat Model

PURPOSE

The purpose of this study was to determine whether the addition of decellularized bovine pericardial patch loaded with mesenchymal stromal cells enhanced bone-to-tendon healing and improved the biomechanical strength of large-to-massive rotator cuff tears in a small animal model.

METHODS

Adipose-derived mesenchymal stromal cells (MSCs) from rat inguinal fat were isolated, cultured, and loaded onto decellularized bovine pericardium patches. To simulate large-to-massive tears, rats were managed with free cage activity for 6 weeks after tear creation. A total of 18 rats were randomly allocated to repair-only (control), repair with pericardial patch augmentation (patch), or repair with MSC loaded pericardial patch augmentation (patch-MSC). Each group had 6 rats (one shoulder of each rat was used for histological evaluation and another for biomechanical evaluation). MSCs seeded on the pericardial patches were traced on four shoulders from 2 other rats at 4 weeks after surgery. Histological evaluation for bone-to-tendon healing and biomechanical testing was carried out at 8 weeks after repair.

RESULTS

MSCs tagged with a green fluorescent protein were observed in the repair site 4 weeks after the repair. One shoulder each in the control and patch groups showed complete discontinuity between the bone and tendon. One shoulder in the control group showed attenuation with only a tenuous connection. Fibrocartilage and tidemark formation at the bone-to-tendon interface (P = .002) and collagen fiber density (P = .040) and orientation (P = .003) were better in the patch-MSC group than in the control or patch group. Load-to-failure in the patch-MSC and patch groups was higher than that in the control group (P = .001 and .009, respectively).

CONCLUSION

Decellularized bovine pericardial patches loaded with adipose-derived and cultured mesenchymal stromal cells enhanced healing in terms of both histology and mechanical strength at 8 weeks following rotator cuff repair in a rat model.

CLINICAL RELEVANCE

Large-to-massive rotator tears need a strategy to prevent retear and enhance healing. The addition of decellularized bovine pericardial patch loaded with MSCs can enhance bone-to-tendon healing and improve biomechanical healing of large-to-massive rotator cuff tears following repair.

Dermal Allograft Augmentation for Rotator Cuff Tears

Large and massive rotator cuff tears continue to be challenging for shoulder surgeons. Given the high percentage of retears after repair of these tears, several surgical technical advancements have been proposed. The use of grafts (xenograft, synthetic, and allograft) as an augmentation of the repair has been growing over the last several years in an attempt to improve structural integrity and postoperative outcomes. Patch augmentation with dermal allografts is the most commonly used, showing promising biomechanical, structural, and functional outcomes. Several factors have been associated with healing outcomes, including age, tear size, and fatty degeneration. The rotator cuff healing index can be used to assess for patients with Hamada grades 1 and 2 with elevated retear risk and potential indications for repair with graft augmentation. A score of 7 points represents a reasonable threshold for the addition of a dermal allograft due to a significant reduction in healing rates when comparing patients with a score of 6 points (66%) to 7 points (only 38%) without augmentation of the repair. Biomechanical studies have demonstrated a greater maximum failure load compared with standard repair. The healing rates of rotator cuff repairs using scaffolds range between 60% and 85%, compared with 40% with nonaugmented repairs. Moreover, the use of repair augmentation has been associated with improved range of motion and functional scores compared with nonaugmented repairs, with allografts showing the best visual analog scale pain score and postoperative external rotation results. Given these favorable healing rates, functional outcomes, and low complication rates, augmenting rotator cuff repairs with a dermal allograft may be a suitable option in active patients with a diminished chance of postoperative healing.

Patch augmentation does not provide better clinical outcomes than arthroscopic rotator cuff repair for large to massive rotator cuff tears

PURPOSE

Patch augmentation for large and massive rotator cuff tears (LMRCTs) has been suggested as a repair strategy that can mechanically reinforce tendons and biologically enhance healing potential. The purpose of this study was to determine whether patients who underwent patch augmentation would have lower rates of retears and superior functional outcomes.

METHODS

Patients who underwent arthroscopic rotator cuff repair (ARCR) with patch augmentation (group A) were matched by age, sex, degree of retraction, and supraspinatus muscle occupation ratio to those treated with ARCR without using a patch (group B) with a minimum follow-up of 24 months. The retear (Sugaya IV or V) rates were evaluated by magnetic resonance imaging at 3 and 12 months post-surgery. The Constant- Murley Score (CMS), Korean Shoulder Score (KSS), and University of California-Los Angeles Shoulder Rating Scale (UCLA) score were retrospectively analyzed.

RESULTS

This study included 34 patients (group A, n = 17; group B, n = 17). The mean follow-up period was 46.5 ± 17.4 months. At postoperative 1-year follow-up, group B (6 patients, 35.3%) showed higher rates of retears than group A (1 patient, 5.9%), which was statistically significant (P = 0.034). However, the postoperative CMS, KSS, and UCLA scores did not differ between the two groups at 3 months, 12 months, and the final follow-up. Additionally, the clinical outcomes of patients with retear were not significantly different from those of the healed patients in both groups.

CONCLUSION

The use of an allodermal patch for LMRCT is effective in preventing retears without complications. However, the clinical outcomes of ARCR using allodermal patch augmentation were not superior to those of only ARCR.

LEVEL OF EVIDENCE

III.

Satisfactory functional and structural outcomes of anterior cable reconstruction using the proximal biceps tendon for large retracted rotator cuff tears

PURPOSE

Large retracted anterior L-shaped tear characterized by a retracted supraspinatus tendon to the glenoid level combined with a relatively preserved infraspinatus tendon is one of the challenging tear patterns in achieving complete repair to the anatomic footprint. The purpose of this study was to evaluate clinical outcomes and tendon integrity of rotator cuff repair combined with anterior cable reconstruction using the proximal biceps tendon in patients with large retracted anterior L-shaped rotator cuff tear.

METHODS

This study prospectively enrolled patients who underwent arthroscopic anterior cable reconstruction using the proximal biceps tendon for large retracted anterior L-shaped rotator cuff tears between 2018 and 2020 with a minimum 2-year follow-up. The anterior portion of the rotator cable was reconstructed using tenotomized proximal biceps tendon fixed with two suture anchors at the footprint. The retracted supraspinatus tendon was repaired on the biceps tendon without undue tension. The proximal portion of the infraspinatus tendon was repaired with the biceps tendon-supraspinatus tendon complex. Clinical outcomes was assessed during the follow-up period. Tendon integrity and retear size were evaluated by postoperative MRI.

RESULTS

A total of 32 consecutive patients were included. The ASES score was significantly improved from 66.6 ± 16.6 preoperatively to 94.1 ± 6.1 postoperatively (P < 0.001), and the VAS for pain was significantly relieved from 2.8 ± 1.9 preoperatively to 0.5 ± 0.4 postoperatively (P < 0.001). All patients were satisfied postoperatively regardless of tendon integrity (P = 0.015). Postoperative ROM was increased continuously during the follow-up period (P < 0.001). The Popeye sign was found in 4 patients (12.5%). Six patients (18.7%) had rotator cuff retears. However, the ASES score of patients with retear was significantly improved from 72.8 ± 13.3 preoperatively to 91.1 ± 6.7 postoperatively (P < 0.001). Relative changes in the retear size compared with the primary tear size were -56.8 ± 14.4% for the anteroposterior diameter and - 70.6 ± 6.1% for the mediolateral diameter.

CONCLUSIONS

Rotator cuff repair combined with anterior cable reconstruction using the proximal biceps tendon provided satisfactory clinical and radiological outcomes for large retracted anterior L-shaped tears. Anterior cable reconstruction using the proximal biceps tendon is a sound surgical option for the patients with large retracted anterior rotator cuff tear.

LEVEL OF EVIDENCE

IV.

Editorial Commentary: Rotator Cuff Repair: Graft Augmentation Provides Promising Clinical Outcomes

Rotator cuff repair has benefitted from many technologic advances including the advent of arthroscopy, improved implant materials, and refined repair techniques. Despite our efforts to improve the science of rotator cuff repair, clinical advances have lagged far behind. Graft augmentation of rotator cuff repairs is an emerging and heterogeneous field that has significantly improved both healing rates and patient-reported metrics in initial data reporting. Treatment algorithms that guide the use of this novel surgical modality are of benefit to practicing orthopaedic surgeons.

Loading Mesenchymal Stem Cell-Derived Exosomes Into a Traditionally Designed Rotator Cuff Patch: A Potential Strategy to Enhance the Repair of Chronic Rotator Cuff Tear Associated With Degenerative Changes

BACKGROUND

Retraction and degenerative changes of chronic rotator cuff tears limit the healing capacity after routine surgical repair.

PURPOSE

To fabricate a mesenchymal stem cell-derived exosome (MSC-Exos) loaded patch and evaluate the effect of this patch on the activity of rabbit tenocytes in vitro and on the repair of chronic rotator cuff tears associated with degenerative changes in vivo.

STUDY DESIGN

Controlled laboratory study.

METHODS

The MSC-Exos loaded patch was fabricated using a dynamic wet-spinning system. In the in vitro studies, the proliferation and migration activities of tenocytes were evaluated by culturing tenocytes with saline, a fiber-aligned patch, or an MSC-Exos loaded patch. In the in vivo studies, a rabbit model of chronic rotator cuff tear was established and directly repaired, repaired with fiber-aligned patch augmentation (RFPA group), and repaired with MSC-Exos loaded patch augmentation (REPA group). Histological and biomechanical analyses were performed at 4, 8, and 12 weeks after surgery.

RESULTS

An MSC-Exos loaded patch with inner aligned fibers, a loose microstructure, and reliable initial strength was fabricated using a dynamic wet-spinning system. The MSC-Exos loaded patch significantly promoted tenocyte proliferation and migration activities in vitro. In vivo, the REPA group exhibited significantly higher tendon maturing scores at 8 and 12 weeks after surgery compared with both the control and the RFPA groups. Fatty infiltration was significantly reduced in the REPA group at 4, 8, and 12 weeks compared with both the control and the RFPA groups. Biomechanical properties, including load to failure and stress, were also significantly improved at 12 weeks in the REPA group compared with both the control and the RFPA groups.

CONCLUSION

Results in the present study suggested that an MSC-Exos loaded patch was able to enhance the repair of a chronic rotator cuff tear by providing mechanical support and minimizing degeneration.

CLINICAL RELEVANCE

This work supported the idea that loading bioactive MSC-Exos into a traditionally designed rotator cuff patch might exert a better effect on the repair of chronic rotator cuff tears than augmented patch repair alone.

Graft Augmentation of Repairable Rotator Cuff Tears: An Algorithmic Approach Based on Healing Rates

We provide our algorithm for tissue augmentation of rotator cuff repairs based on the current available evidence regarding rotator cuff healing. A variety of factors are associated with healing following rotator cuff repair. Increasing tear size and retraction as well as severe fatty degeneration have been associated with worsening rates of tendon healing. Given the correlation between tendon healing and postoperative outcomes, it is important to identify patients at high risk for failure and to modify their treatment accordingly to minimize the risk of early biomechanical failure and maximize the potential for structural healing. One approach that may be used to improve healing is tissue augmentation. Tissue augmentation is the use of tissue patches and scaffolds to provide rotator cuff reinforcement. Surgical management for rotator cuff tears (RCTs) continues to be a challenging task in orthopaedic surgery today. Appropriate treatment measures require an in depth understanding and consideration of the patient's prognostic factors such as age, fatty infiltration of the rotator cuff muscles, bone mineral density, rotator cuff retraction, anteroposterior tear size, work activity, and degenerative changes of the joint. Using these factors within the Rotator Cuff Healing Index, we can determine a patient's surgical treatment that will yield the maximum healing rate. For nonarthritic RCTs, joint-preserving strategies should be first-line treatment options. For young, active patients with a reparable RCT and minimal fatty infiltration, a complete repair can be effective. For young patients with irreparable RCTs, superior capsular reconstructions, and tendon transfers are viable options. For elderly patients with low work activity, an irreparable RCT and significant fatty infiltration, a partial repair with or without graft augmentation can be attempted if minimal to no arthritic changes are seen. LEVEL OF EVIDENCE: Level V, expert opinion.

Rotator Cuff Repair with Graft Augmentation Improves Function, Decreases Revisions, and Is Cost-Effective

PURPOSE

The purpose of this study is to evaluate the cost effectiveness of the use of extracellular matrix (ECM) augment at the time of primary rotator cuff repair utilizing a decision tree analysis.

METHODS

A decision tree model was created utilizing the existing literature for retear rates with and without dermal graft augmentation. Costs for rotator cuff repair (hospital and surgeon fees) were based on published studies and the cost for graft augmentation was based on institutional data. Utility measures were based upon EQ-5D (European Quality of Life 5 Dimension) scores to assess for improvement in quality adjusted life years (QALY) over a 10-year postoperative period with and without graft augmentation. Cost effectiveness was assessed using the incremental cost effectiveness ratio (ICER), or the incremental cost for per QALY with graft augmentation. Cost effectiveness is based on previous literature whereby an intervention is considered cost effective if the ICER is less than $50,000/QALY.

RESULTS

On the basis of our decision tree analysis, total cost for rotator cuff tear without augmentation was $12,763, while the cost increased to $16,039 with ECM augmentation. With graft augmentation there was an improvement in 2.29 QALY, while there was an improvement of 2.05 without graft augmentation. The ICER of graft augmentation is $14,000/QALY, well below the cost effectiveness cut-off of $50,000/QALY. Sensitivity analysis showed the maximum cost of the ECM augment to be cost effective is $11,921.

CONCLUSION

Graft augmentation does come with a significant upfront cost; however, on the basis of our decision-tree analysis, it may represent a cost-effective procedure. There is evidence to potentially consider more routine use in rotator cuff repairs, while being cost effective.

LEVEL OF EVIDENCE

Economic: Level IV: computer simulation model (Monte Carlo simulation, Markov model) with inputs derived from Level IV studies.

Allograft and autograft provide similar retear rates for the management of large and massive rotator cuff tears: a review and meta-analysis

PURPOSE

Currently, autografts and allografts are largely used to treat large or massive rotator cuff tear (RCT), without any evidence in favour of one graft or the other. The purpose of this study was to determine the rate of retear of autograft and allograft in the treatment of large or massive posterosuperior RCT.

METHOD

The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed to perform this systematic review and meta-analysis of the results in the literature as well as the presentation of results. A search of the literature was performed in the electronic databases MEDLINE, Scopus, Embase, and the Cochrane Library. The quality of the included studies was evaluated according to the MINORS (Methodological Index for Nonrandomized Studies) score. Inclusion criteria were studies in English evaluating clinical and radiological results of surgical treatment with autograft or allograft for large or massive RCT since 2008. The main criterion was the retear rate of the graft assessed on MRI or US scan at 1-year minimum follow-up. Partial tear were classified as "tear".

RESULTS

The overall retear rate was 23.6% (15.5-32.7) at a mean follow-up of 18.4 ± 7.8 (12-36) months. There was no significant difference between the two kinds of graft, with a retear rate of 27.0% (15.4-40.2) and 20.9% (9.9-34.2) with autograft and allograft respectively (n.s.). Similar improvements of functional scores (+ 28.8 to 38.4 points for the Constant score, + 33.6 to 38.4 points for the ASES, and - 4.0 to - 4.1 points for pain-VAS) were reported in the two groups after at 27.2 ± 11.1 (12-48) months. The rate of complications except retear was 1.8% (0.2, 3.7) with autograft and 0.5% (0.8, 1.8) with allograft (n.s.).

CONCLUSION

The use of autograft and allograft for the treatment of large or massive RCT leads to similar retear rate and clinical outcomes at short to medium terms.

LEVEL OF EVIDENCE

Level IV.

Clinical Outcomes following Biologically Enhanced Demineralized Bone Matrix Augmentation of Complex Rotator Cuff Repair

Complex rotator cuff tears provide a significant challenge for treating surgeons, given their high failure rate following repair and the associated morbidity. The purpose of this study is to evaluate the clinical outcomes of patients who underwent biologically enhanced demineralized bone matrix augmentation of rotator cuff repairs. Twenty patients with complex rotator cuff tears underwent arthroscopic rotator cuff repair by a single surgeon with demineralized bone matrix (DBM) augmentation that was biologically enhanced with platelet-rich plasma and concentrated bone marrow aspirate. Post-operative MRI was used to determine surgical success. Patient reported outcome measures and range of motion data were collected pre-operatively and at the final post-operative visit for each patient. Ten patients (50%) with DBM augmentation of their arthroscopic rotator cuff repair were deemed non-failures. The failure group had less improvement of visual analogue pain scale (p = 0.017), Simple Shoulder Test (p = 0.032), Single Assessment Numerical Evaluation (p = 0.006) and abduction (p = 0.046). There was no difference between the groups for change in American Shoulder and Elbow Society score (p = 0.096), Constant-Murley score (p = 0.086), forward elevation (p = 0.191) or external rotation (p = 0.333). The present study found that 50% of patients who underwent biologically enhanced DBM augmentation of their rotator cuff repair demonstrated MRI-determined failure of supraspinatus healing.

Prospective 1-Year Outcomes Are Maintained at Short-Term Final Follow-Up After Superior Capsular Reconstruction Augmentation of Complete Rotator Cuff Repair

PURPOSE

To evaluate the outcomes of arthroscopic superior capsular reconstruction (SCR) augmentation of complete, massive rotator cuff repair (RCR).

METHODS

A retrospective study of dermal allograft SCR-augmented RCRs performed by a single surgeon from June 2016 through December 2017 was performed with the following inclusion criteria: massive rotator cuff tear amenable to complete repair but with poor-quality native rotator cuff tissue. Radiographic follow-up was performed at 1 year, and clinical follow-up was performed at both 1 year and a minimum 2 years after surgery. Clinical follow-up included the American Shoulder and Elbow Surgeons score, visual analog scale score for pain, Subjective Shoulder Value score, active forward elevation, and external rotation. Radiographs and magnetic resonance imaging (MRI) scans were assessed for muscle quality using the Goutallier classification, and graft and cuff integrity was assessed according to the Sugaya classification.

RESULTS

The inclusion criteria were met by 24 patients at 1 year and by 18 (75%) at a minimum of 2 years postoperatively. Patient-reported outcomes were improved compared with preoperative data and were maintained at minimum 2-year follow-up, with median American Shoulder and Elbow Surgeons scores of 42.5 (interquartile range [IQR], 30.8-58.7) versus 93.9 (IQR, 82.4-100) (P < .001); median Subjective Shoulder Value scores of 30 (IQR, 20-50) versus 90 (IQR, 86.2-97.2) (P < .001); and median visual analog scale pain scores of 5.5 (IQR, 1-9) versus 0 (IQR, 0-0.8) (P = .001). Evaluation of graft and tendon healing on postoperative MRI revealed poor interobserver agreement and showed 10 completely healed grafts (42%), 9 partially healed grafts (38%), and 5 completely disrupted grafts (21%), with 42% of supraspinatus tendons and 54% of infraspinatus tendons healed.

CONCLUSIONS

SCR with dermal allograft augmentation of complete RCR with poor-quality tissue shows very good clinical outcomes at minimum 2-year follow-up. Poor interobserver agreement regarding postoperative graft and rotator cuff integrity by MRI was found. The healing rate for the SCR grafts was 79%. The rates of healing of the native supraspinatus and infraspinatus tendons were 42% and 54%, respectively.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Use of an Arthroscopic Bridging Graft for Irreparable Rotator Cuff Tears With the Modified Mason-Allen Stitch Using a Tendon Autograft

We describe a technique for treating irreparable rotator cuff tears (RCTs) by bridging grafts with a long tendon autograft. In this technique, the plantaris tendon is harvested and prepared in a Y-shaped graft. The folded end of the graft is anchored to the greater tubercle and the other 2 limbs are fixed to rotator cuff tissue using modified Mason-Allen stitches. The autograft can decrease the tension on the repair of irreparable RCTs and has biological superiority. Our clinical experience indicates this technique will bring superior integrity to irreparable RCT repairs.

Benefits of Patch Augmentation on Rotator Cuff Repair: A Systematic Review and Meta-analysis

Background:

Despite technological advances, the overall retear rate on rotator cuff repair is still high. Patches have shown significant reduction in retear rate and pain scores; however, this is not a universal finding and conflicting results have been shown among functional shoulder scales.

Purpose:

To analyze previous controlled trials of the literature to bring a consensus about the effectiveness of patch use on rotator cuff repair.

Study Design:

Systematic review; Level of evidence, 1.

Methods:

The search was conducted in PubMed, Web of Science, EMBASE, Scopus, and Cochrane in April 2020. The results of rotator cuff repair with patch augmentation versus without augmentation (control) were compared through odds ratio (OR), raw mean difference (RMD), and standardized mean difference (SMD) of retear rate; functional shoulder scales; strength; and range of motion (ROM).

Results:

Of 733 initial studies, 7 of them met the criteria to be included in the analysis. Compared with the control group, the patch augmentation group had a significantly lower retear rate (OR, 0.32 [95% CI, 0.18 to 0.55]; P < .001), lower pain (SMD, –0.42 [–0.71 to –0.12]; P < .01), a higher University of California Los Angeles Shoulder Rating Scale (RMD, 0.87 [0.15 to 1.60], P = .017), and a trend toward higher strength (SMD, 0.95 [–0.03 to 1.94], P = .05) and lower forward elevation ROM (RMD, –10.50 [–21.86 to 0.67]; P = .06), while no changes were noted for other functional scales or for internal and external rotation ROM.

Conclusion:

The results point to benefits of patch augmentation in rotator cuff repair, particularly a reduction in retear rate. More interventional studies with better methodological quality should be conducted to confirm the results of this initial review.

Arthroscopic Rotator Cuff Repair with Biphasic Interpositional Allograft Augmentation

Rotator cuff repair in the setting of a chronic tear or poor tissue quality presents a surgical challenge because of the high risk of structural failure. Patients with an increased risk of retear may be candidates for enthesis augmentation with a novel, biphasic allograft, composed of a demineralized cancellous matrix with a layer of mineralized bone. This interpositional graft was designed with the intention to promote both soft-tissue and osseous integration into the matrix, thereby conferring greater stability and regeneration of the transitional zone of the rotator cuff enthesis. Here, we describe a technique for a transosseous-equivalent supraspinatus repair with placement of a biphasic interpositional allograft.

Achilles Tendon–Bone Block Allograft for Massive Rotator Cuff Tears With Bony Deficiency of the Greater Tuberosity: A Minimum 2-Year Follow-up Study

Background:

Massive rotator cuff tears associated with greater tuberosity bone loss are challenging to treat. Repairing the rotator cuff without addressing the greater tuberosity deficiency may result in poorer clinical outcomes.

Hypothesis:

Utilizing an Achilles tendon–bone block allograft to address both the massive rotator cuff tear and greater tuberosity bone loss concurrently can result in improved clinical outcomes.

Study Design:

Case series; Level of evidence, 4.

Methods:

The authors performed a retrospective study of patients treated between January 2011 and December 2018 with Achilles tendon–bone block allograft for massive rotator cuff tears associated with greater tuberosity bone loss. The inclusion criteria were massive rotator cuff tear and bony deficiency of the greater tuberosity; patients with a history of bony metabolism disease, connective tissue disease, and previous surgery to the wrist or elbow of the affected limb were excluded. Range of motion, visual analog scale for pain, Constant score, and Single Numeric Assessment Evaluation score were assessed preoperatively and at a minimum of 2 years postoperatively. Radiographs and ultrasound images were evaluated to assess allograft union and rotator cuff integrity.

Results:

Five patients (3 male and 2 female; mean age, 54.0 ± 12.2 years) were included in the study. The mean follow-up was 80.6 ± 33.7 months. Preoperative to postoperative values improved significantly on the visual analog scale (from 45.8 ± 25.5 to 14.5 ± 14.1; P = .04), Constant score (from 36.8 ± 7.9 to 73.5 ± 3.1; P < .001), and Single Numeric Assessment Evaluation score (from 42.5 ± 26.3 to 82.5 ± 10.4; P = .04). Forward flexion improved significantly from 53° ± 47° to 149° ± 17° (P = .03). Four of the 5 patients achieved bony union. One patient required removal of symptomatic hardware at 6 months postoperatively, and 1 patient required revision surgery at 1 year postoperatively because of progressive osteonecrosis of the humeral head.

Conclusion:

In patients with massive rotator cuff tears and a greater tuberosity bony deficiency, utilizing an Achilles tendon–bone block allograft to restore the bony defect and reinforce the rotator cuff repair was safe and effective. At a minimum of 2 years postoperatively, most patients demonstrated improved clinical outcomes, tendon healing, and graft incorporation.

Rotator Cuff Repair Using Coracoacromial Ligament Autograft for Supraspinatus Footprint Augmentation

Failure of rotator cuff repair can be a disastrous clinical outcome. Although failure is a multifactorial issue, recent interest has piqued in understanding the biology of the insertional components of the supraspinatus and infraspinatus at the footprint. When the torn tendon is of poor quality, especially if it is diminutive or thin, rotator cuff repair augmentation should be considered to aid in long-term healing. Various allograft options have been described in the past, and more recently, xenografts and synthetics have become more commonly used. The use of autografts in the treatment of insertional footprint deficiency has great potential; however, few grafts have been described. This study describes the surgical technique for footprint augmentation in arthroscopic supraspinatus repair using harvested autologous coracoacromial ligament tissue.

Technical Note: Arthroscopic Rotator Cuff Repair with Patch Augmentation with Acellular Dermal Allograft

Rotator cuff tears are one of the most common causes of shoulder pain and dysfunction seen by orthopaedic surgeons. Although rotator cuff repair (RCR) has been shown to provide optimal outcomes, retear rates average roughly 60% and have been reported to exceed 90%. Retear after RCR is especially prevalent in patients with large, multitendon tears with poor tissue quality. Allograft augmentation of RCR may reinforce anatomically reparable tears, particularly in patients with poor tissue quality. Although various techniques of patch augmented RCR have been described, the procedure remains challenging. This Technical Note describes RCR augmented with acellular dermal allograft using the CuffMend system (Arthrex Inc, Naples, FL), which significantly decreases surgeon demand and helps avoid the pitfalls common with this procedure.

Diagnosis and Management of Partial Thickness Rotator Cuff Tears: A Comprehensive Review

Partial thickness rotator cuff tears (PRCTs) are a challenging disease entity. Optimal management of PRCTs continues to be controversial. Although advances in magnetic resonance imaging and ultrasonography have aided in early diagnosis, arthroscopic evaluation remains the benchmark for diagnosis. Conservative treatment is often the first line of management for most patients; however, evidence suggests that surgical intervention may limit tear progression and the long-term sequelae. Surgical decision making is driven by factors such as age, arm dominance, etiology, activity level, tear thickness, and tear location. Many surgical options have been described in the literature to treat PRCTs including arthroscopic débridement, transosseous, in situ repair techniques, and tear completion and repair. Biologic supplements have also become an attractive alternative to aid in healing; however, the long-term efficacy of these modalities is largely unknown. This article will provide a detailed review of the etiology and natural history of PRCTs, as well as diagnosis, and current management to guide clinical decision-making and formulate an algorithm for management of PRCTs for the orthopaedic surgeon.

The Evolution of Arthroscopic Rotator Cuff Repair

Over the past 30 years, arthroscopic rotator cuff repair (ARCR) has evolved to become the gold standard in treating rotator cuff pathology. As procedural concepts of ARCR continue to improve, it is also continually compared with the open rotator cuff repair as the historical standard of care. This review highlights the evolution of ARCR, including a historical perspective; the anatomic, clinical, and surgical implications of the development of an arthroscopic approach; how arthroscopy improved some of the problems of the open approach; adaptations in techniques and technologies associated with ARCR; future perspectives in orthobiologics as they pertain to ARCR; and lastly, the clinical improvements, or lack of improvements, with all of these adaptations.

Treatment Options for Massive Irreparable Rotator Cuff Tears

PURPOSE OF REVIEW

Massive irreparable rotator cuff tears present a significant challenge to the orthopedic surgeon. No single treatment, particularly among joint-preserving options, has been shown to be superior. The purpose of this review is to discuss recent advances in the treatment of massive irreparable rotator cuff tears, including partial repair with and without graft augmentation, interposition grafts, superior capsule reconstruction, subacromial balloon spacers, tendon transfer, and reverse total shoulder arthroplasty. We will also offer guidance on surgical indications based on our clinical experience.

RECENT FINDINGS

Partial repair may offer reasonable clinical improvement for patients with lower preoperative function despite high re-tear rates. Additionally, several types of interposition grafts have shown promising short-term results and may outperform repair alone. Subacromial balloon spacers may lead to clinical improvement, especially in patients without glenohumeral osteoarthritis or pseudoparalysis, and recently received FDA approval for use in the USA. Superior capsule reconstruction is a technically demanding procedure that appears to produce excellent short-term results particularly when performed at high volume, but long-term studies in heterogeneous study groups are needed. Tendon transfers improve function by restoring force coupling in the shoulder, offering a promising option for younger patients. Reverse total shoulder arthroplasty (RTSA) is a reliable option for treatment of irreparable cuff tears in elderly patients with lower functional demands. Irreparable cuff tears remain a difficult condition to treat. Recommended treatment for younger patients without glenohumeral osteoarthritis is particularly controversial. For older patients with low-demand lifestyles and glenohumeral osteoarthritis, RTSA is an effective treatment option. For all discussed procedures, patient selection appears to play a critical role in clinical outcomes.

Treatment of Partial-Thickness Rotator Cuff Tears With a Resorbable Bioinductive Bovine Collagen Implant: 1-Year Results From a Prospective Multicenter Registry

Background:

Surgical treatment of partial-thickness rotator cuff tears remains challenging and controversial, with several traditional options including debridement with acromioplasty, transtendon or in situ repair, and take-down and repair. A resorbable bioinductive bovine collagen implant has shown promise as an alternative treatment option for partial-thickness tears.

Purpose:

Data from a registry were analyzed to further establish that the implant contributes to improved patient-reported outcome (PRO) scores across a large number of patients treated for partial-thickness rotator cuff tears.

Study Design:

Case series; Level of evidence, 4.

Methods:

A total of 19 centers in the United States enrolled patients >21 years old with partial-thickness tears of the rotator cuff in a comprehensive prospective multicenter registry. PRO scores were recorded preoperatively and postoperatively at 2 and 6 weeks, 3 and 6 months, and 1 year: American Shoulder and Elbow Surgeons, Single Assessment Numeric Evaluation, Veterans RAND 12-Item Health Survey (physical and mental component scores), and Western Ontario Rotator Cuff scores. Revisions were reported throughout the study.

Results:

The registry included 272 patients with partial-thickness tears (49 grade 1 tears, 101 grade 2 tears, and 122 grade 3 tears), 241 who underwent isolated bioinductive repair (IBR; collagen implant placed after bursectomy without a traditional rotator cuff repair), and 31 who had take-down and repair with bioinductive augmentation. Patients experienced statistically significant and sustained improvement from baseline for all PRO scores beginning at 3 months. Among patients with grade ≥2 tears, those with take-down and repair had significantly inferior scores at 2 and 6 weeks for most PRO scores as compared with those who underwent IBR, but the difference was no longer significant at 1 year for all but the physical component score of the Veterans RAND 12-Item Health Survey. There were 11 revisions, which occurred at a mean ± SD of 188.7 ± 88.0 days after the index surgery. There were no infections.

Conclusion:

This registry analysis further establishes across a large data set that this resorbable bioinductive bovine collagen implant improves PROs in all grades of partial-thickness tears, whether used as IBR or in conjunction with take-down and repair. IBR may offer improved early clinical outcomes (≤6 weeks) and comparable outcomes at 1 year when compared with a more invasive “take-down and repair” approach.

Healing and Functional Results of Dermal Allograft Augmentation of Complex and Revision Rotator Cuff Repairs

BACKGROUND

Primary rotator cuff repairs in complex cases (older patient age, larger tear sizes, chronic tears) and revision repairs are at high risk for failure of healing.

PURPOSE

To examine clinical outcomes and healing rates in complex and revision rotator cuff repairs with dermal allograft augmentation.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A retrospective study was made of cases performed by 3 fellowship-trained surgeons via a uniform technique involving rotator cuff repairs with allograft augmentation. In all cases, a 1.5-mm, human, decellularized dermal graft was tied on top of the tendon at the medial row and compressed to the rotator cuff footprint using a double-row technique. Postoperative magnetic resonance imaging (MRI) was performed at a minimum of 6 months and American Shoulder and Elbow Surgeons (ASES), Single Assessment Numeric Evaluation (SANE), and 12-Item Short Form Health Survey scores were collected at a minimum of 2 years postoperatively.

RESULTS

A total of 35 patients (23 revision repairs, 12 primary complex repairs) were included. The mean patient age was 57.9 years (range, 41.0-70.5 years). All shoulders had 2-tendon tears (supraspinatus and infraspinatus), and 8 included the upper 50% of the subscapularis. At a minimum of 2 years after surgery (mean, 3.2 years), mean ASES and SANE scores improved from 42.4 and 35.3 to 77.6 and 73.5, respectively (P < .001). In the 23 patients (66%) with postoperative MRI evaluation, 11 (48%) had images showing the tendons were retorn. ASES (89.7 vs 66.4; P = .04) and SANE (84.1 vs 50.5; P = .02) scores were higher in healed patients than those with retears. The retear group had a higher degree of preoperative fatty atrophy of the infraspinatus (P = .024).

CONCLUSION

Double-row arthroscopic repair with dermal allograft augmentation of complex and revision rotator cuff tears led to improved functional outcomes. Approximately half of patients experienced a failure of healing, which was associated with poorer functional results.

Does Margin Convergence Reverse Pseudoparalysis in Patients with Irreparable Rotator Cuff Tears?

BACKGROUND

Margin convergence has been shown to restore muscle tension in a cadaveric model of a rotator cuff tear. However, the clinical utility of this technique remains uncertain for patients with pseudoparalysis caused by an irreparable rotator cuff tear.

QUESTIONS/PURPOSES

(1) For patients with massive irreparable rotator cuff tears, in what proportion of patients does margin convergence reverse pseudoparalysis? (2) In patients with massive irreparable rotator cuff tears, does margin convergence improve American Shoulder and Elbow Surgeons (ASES) scores? (3) What is the survivorship free from MRI evidence of retear after margin convergence?

METHODS

Between 2000 and 2015, we treated 203 patients for pseudoparalysis with a rotator cuff tear. Pseudoparalysis was defined as active elevation less than 90° with no stiffness, which a physical therapist evaluated in the sitting position using a goniometer after subacromial injection of 10 cc lidocaine to eliminate pain. Of those, we considered patients who underwent at least 3 weeks of unsuccessful nonoperative treatment in our hospital as potentially eligible. Twenty-one percent (43 of 203) who either improved or were lost to follow-up within 3 weeks of nonoperative treatment were excluded. A further 12% (25 of 203) were excluded because of cervical palsy, axillary nerve palsy after dislocation or subluxation, and development of severe shoulder stiffness (passive shoulder elevation < 90°). Repair was the first-line treatment, but if tears were considered irreparable with the torn tendon unable to reach the original footprint after mobilizing the cuff during surgery, margin convergence was used. When margin convergence failed, the procedure was converted to hemiarthroplasty using a small humeral head to help complete the repair. Therefore, 21% (42 of 203) of patients treated with regular repair (18% [36 of 203]) or hemiarthroplasty (3% [6 of 203]) were excluded. That left 93 patients eligible for consideration. Of those, 13 patients were lost before the minimum study follow-up of 2 years or had incomplete datasets, and 86% (80 of 93) were analyzed (49 men and 31 women; mean age 68 ± 9 years; mean follow-up 26 ± 4 months). Seventy-six percent (61 of 80) were not evaluated in the last 5 years. We considered reversal of pseudoparalysis as our primary study outcome of interest; we defined this as greater than 90° active forward elevation; physical therapists in care measured this in the sitting position by using goniometers. Clinical outcomes were evaluated based on the ASES score from chart review, active ROM in the shoulder measured by the physical therapists, and the 8-month Kaplan-Meier survivorship free from MRI evidence of retear graded by the first author.

RESULTS

Pseudoparalysis was reversed in 93% (74 of 80) patients, and improvement in ASES scores was observed at the final follow-up (preoperative 22 ± 10 to postoperative 62 ± 21, mean difference 40 [95% CI 35 to 45]; p < 0.01). The 8-month Kaplan-Meier survivorship free from MRI evidence of retear after surgery was 72% (95% CI 63% to 81%). There were no differences in clinical scores between patients with and without retears (intact ASES 64 ± 24, re-tear ASES 59 ± 10, mean difference 6 [95% CI -5 to 16]; p = 0.27).

CONCLUSION

Margin convergence can be a good option for treating patients with pseudoparalysis and irreparable rotator cuff tears despite the relatively high retear rates. The proportion of pseudoparalysis reversal was lower in patients with three-tendon involvement. Further studies will be needed to define the appropriate procedure in this group.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Cost of Arthroscopic Rotator Cuff Repairs Is Primarily Driven by Procedure-Level Factors: A Single-Institution Analysis of an Ambulatory Surgery Center

PURPOSE

To identify intraoperative drivers of cost associated with arthroscopic rotator cuff repairs (RCRs) through analysis of an institutional database.

METHODS

This was a single-institution retrospective review of arthroscopic RCRs performed at an ambulatory surgical center between November 2016 and July 2019. Patient-level factors analyzed included age, sex, insurance type (private, Medicare, Medicaid, self-pay, and other government), American Society of Anesthesiologists grade (I, II, III, and missing), and Charlson comorbidity index (0, 1, 2, and ≥3). Procedure-level factors included use of biologics (decellularized dermal allograft or bioinductive healing implant), anesthesia type (regional block, monitored anesthesia care, or general), number of anchors and sutures, additional procedures (biceps tenodesis, distal clavicle resection, subacromial decompression), and operative time. Multivariate linear regression analysis was used to identify factors significantly associated with higher or lower charges.

RESULTS

A total of 712 arthroscopic RCRs were included. The risk-adjusted operative charges were $19,728 (95% confidence interval $16,543 to $22,913). The above factors predicted nearly 65% of the variability in operative charges. The only patient-level factor significantly associated with lower charges was female sex (- $1,339; P = .002). Procedure-level factors significantly associated with higher charges were use of biologics (+ $17,791; P < .001), concurrent open biceps tenodesis (+ $4,027; P < .001), distal clavicle resection (+ $2,266; P = .039), use of regional block (+ $1,256; P = .004), number of anchors (+ $2,245/anchor; P < .001), and increasing operative time ($26/min). Other factors had no significant association.

CONCLUSIONS

Procedural factors are the most significant drivers of operative cost in arthroscopic RCRs, such as quantity and type of implants; additional procedures such as biceps tenodesis and distal clavicle resection; and perioperative conditions such as type of anesthesia and total operating room time. Overall, patient-level factors were not shown to correlate well with operative costs, other than lower charges with female sex.

LEVEL OF EVIDENCE

IV, economic study.

Surgical Technique for Arthroscopic Rotator Cuff Augmentation With Human Acellular Dermal Matrix

Arthroscopic repair is probably the gold standard for treating large rotator cuff tears. Although positive, the results of this type of intervention depend on many factors such as the size of the tear, the age of the patient, and the number of previous surgeries. To decrease the rate of recurrence, we propose a surgical technique for augmenting the repair using an acellular dermal matrix (ArthroFlex, LifeNet Health). Our technique allows the surgeon to initially suture the tear in a regular fashion without visual interference. Once the tear is repaired, the augmentation is performed in a simple, all-arthroscopic, reproducible, and safe way. Also, we do not use extra implants for the fixation of the graft, so it does not increase the cost of the procedure (leaving aside the cost of the matrix itself).

[Irreparable rotator cuff tear-reverse shoulder arthroplasty and alternative procedures]

Irreparable rotator cuff tears represent a significant everyday clinical challenge. A high degree of tendon retraction and muscle degeneration means that a direct reconstruction is impossible. Patients often suffer from pain and pseudoparalysis. In older patients this can reliably be resolved by the implantation of a semiconstrained inverse shoulder prosthesis; however, for younger patients joint-preserving techniques should be employed. Furthermore, for frail older patients who may not be suitable for a joint replacement operation, alternative treatment strategies are required. Management options include physiotherapy and pain relieving or reconstructive operations. Minimally invasive arthroscopic treatment approaches can lead to pain relief and slight functional improvements in selected patients; however, to restore the active movement of the joint a partial cuff repair, augmentation with a graft or replacement with muscle transfer is necessary. This article presents the various treatment options and the results reported in the literature. Through this a treatment algorithm is suggested in order to facilitate management decisions.