The Role of Biologic Therapy in Rotator Cuff Tears and Repairs

Augmentation of a Transosseous-Equivalent Repair in Posterosuperior Nonacute Rotator Cuff Tears With a Bioinductive Collagen Implant Decreases the Retear Rate at 1 Year: A Randomized Controlled Trial

PURPOSE

To determine whether the addition of a bioinductive collagen implant (BCI) over a transosseous equivalent (TOE) repair of medium-to-large posterosuperior rotator cuff tears improves the healing rate determined by magnetic resonance imaging (MRI) at 12-month follow-up.

METHODS

A Level I randomized controlled trial was performed in 124 subjects with isolated, symptomatic, reparable, full-thickness, medium-to-large posterosuperior nonacute rotator cuff tears, with fatty infiltration ≤2. These were randomized to 2 groups in which an arthroscopic posterosuperior rotator cuff tear TOE repair was performed alone (Control group) or with BCI applied over the TOE repair (BCI group). The primary outcome was the retear rate (defined as Sugaya 4-5) determined by MRI at 12 months of follow-up. Secondary outcomes were characteristics of the tendon (Sugaya grade and thickness of the healed tendon) and clinical outcomes (pain levels, EQ-5D-5L, American Shoulder and Elbow Surgeons, and Constant-Murley scores) at 12 months of follow-up.

RESULTS

Of the 124 randomized patients, 122 (60 in the BCI group and 62 in the Control group) were available for MRI evaluation 12.2 ± 1.02 months after the intervention. There were no relevant differences in preoperative characteristics. Adding the BCI reduced the retear rate (8.3% [5/60] in the BCI group vs 25.8% [16/62] in the Control group, P = .010; relative risk of retear of 0.32 [95% confidence interval 0.13-0.83]). Sugaya grade was also better in the BCI group (P = .030). There were no differences between groups in the percentage of subjects who reached the MCID for CMS (76.7% vs 81.7%, P = .654) or American Shoulder and Elbow Surgeons (75% vs 80%, P = .829), in other clinical outcomes or in complication rates at 12.4 ± 0.73 (range 11.5-17) months of follow-up.

CONCLUSIONS

Augmentation with a BCI of a TOE repair in a medium-to-large posterosuperior rotator cuff tear reduces the retear rate at 12-month follow-up by two-thirds, yielding similar improvements in clinical outcomes and without increased complication rates.

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

Effect of Platelet-Rich Plasma Dosing for Healing after Arthroscopic Cuff Repair Compared with Surgery Alone: A Systematic Review and Meta-Analysis

INTRODUCTION

Platelet-rich plasma (PRP) has been used for arthroscopic rotator cuff repairs (aRCR), but no studies have addressed the impact of platelet concentration. The primary aim was to evaluate whether the PRP cell concentration has an effect on tendon healing after aRCR compared with surgery alone. The secondary aim was to assess the functional and pain outcomes.

MATERIALS AND METHODS

A systematic review was performed with searches in the MEDLINE (PubMed), Scopus, Web of Science, and Cochrane (Central) databases according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Metanalytic procedures were performed for randomized controlled trials (RCTs), and a subgroup analysis was used for studies with target (approximately 10 6 cells·μL -1 ) or below-target PRP cellular concentrations (app. 5 × 10 5 cells·μL -1 ) regarding the primary outcome of tendon healing.

RESULTS

This review included 10 studies (8 RCTs) with 342 patients in the aRCR + PRP group and 344 patients with isolated aRCR. The risk of bias was low to intermediate (6/4, respectively). Meta-analysis of the RCT revealed that the aRCR + high-concentration PRP group had an approximately 3.9-fold higher chance of healing than the non-PRP group (odds ratio, 3.89; 95% confidence interval, 1.78-8.44; P = 0.0007). No significant difference in healing was found between the aRCR + low-concentration PRP and non-PRP groups (odds ratio, 2.21; 95% confidence interval, 0.66-7.45; P = 0.2). The Constant-Murley score and University of California Los Angeles scores were significantly improved in the aRCR + PRP groups with more than 12 months of follow-up, and no significant differences were found consistently for the American Shoulder and Elbow Society and visual analog scale scores.

CONCLUSIONS

This study highlights that a PRP cell concentration close to the target (10 6 cells·μL -1 ) of patients with aRCR may improve their healing and functional outcomes and that dosing may be potentially useful in therapy.

Editorial Commentary: Biologic Augmentation of Rotator Cuff Repair: Platelet-Rich Plasma May Be of Significant Benefit, Whereas Atelocollagen Cannot Be Recommended

The field of orthobiologics continues to advance at a rapid pace and theoretically holds some promise to augment the biologic healing response in rotator cuff repair (RCR). However, the clinical evidence for use of substances such as platelet-rich plasma (PRP) for RCR remains inconclusive. Atelocollagen, as a synthetic collagen substitute, has been proposed as another alternative to provide more collagen substrate for healing, but outcomes data with this technique is lacking. In contrast, (biologic) PRP has been well studied, does not show adverse outcomes, and has been shown to improve healing of large to massive tears, as well as RCR outcomes. As biologic augmentation options continue to push the envelope on indications, due diligence is required to carefully examine options for safety and efficacy. Evolutions in RCR should also continue to motivate sports medicine surgeons and researchers to seek out further innovations to improve patient outcomes. That said, PRP outcome improvement for RCR is not definitive and requires further study. RCR can humble even the best of surgeons and demands that we continue to look for ways to improve outcomes.

Arthroscopic Surgery Combined With Platelet-Rich Plasma Does Not Significantly Improve Pain, Function, Complications, and Retear Rate Compared With Arthroscopic Surgery Alone for Full-Thickness Rotator Cuff Tears: A Systematic Review and Meta-analysis

PURPOSE

To evaluate the effectiveness and safety of arthroscopic surgery combined with platelet-rich plasma (PRP) compared with arthroscopic surgery alone in the treatment of patients with full-thickness rotator cuff tears.

METHODS

The Cochrane Library, PubMed, Embase, Scopus, EBSCO, Web of Science, China National Knowledge Infrastructure, and Wanfang Database were systematically searched from inception to November 2023. Subject words combined with free words were used to collect randomized controlled trials focusing on arthroscopic surgery combined with PRP in the treatment of full-thickness rotator cuff tears. The assessment of evidence quality employed the Cochrane Collaboration risk of bias tool, and data analysis was performed using RevMan 5.3 software.

RESULTS

A total of 9 studies with 537 patients were included. The meta-analysis revealed that compared with the arthroscopic surgery alone group, the summary result of University of California Los Angeles score scores in the arthroscopic combined with PRP group was (mean difference [MD] = 1.08, 95% confidence interval [CI] 0.19∼1.97, P = .02), subgroup analysis of surgical suture method visual analog scale (VAS) single-row (MD = -1.00, 95% CI -1.50 to -0.50, P < .0001), VAS double-row (MD = -0.10, 95% CI -0.17 to -0.02, P = .02), and Constant-Murley score single-row (MD = 3.49, 95% CI 0.32∼6.66, P = .03), the difference was statistically significant, and the differences in VAS, Constant-Murley score, and Quick Disabilities of the Arm, Shoulder and Hand, complications, and retear rate were not statistically significant.

CONCLUSIONS

Patients undergoing arthroscopic repair combined with PRP treatment showed no difference in pain, function, complications, and retear rate compared with those treated with arthroscopic surgery alone.

LEVEL OF EVIDENCE

Level II, systematic review and meta-analysis of Level I and II evidence.

The long head of the biceps tendon: a valuable tool in shoulder surgery

ANATOMY AND FUNCTION

The long head of the biceps tendon (LHBT) has different properties and characteristics that render it a valuable tool in the hands of shoulder surgeons. Its accessibility, biomechanical strength, regenerative capabilities, and biocompatibility allow it to be a valuable autologous graft for repairing and augmenting ligamentous and muscular structures in the glenohumeral joint.

SHOULDER SURGERY APPLICATIONS

Numerous applications of the LHBT have been described in the shoulder surgery literature, including augmentation of posterior-superior rotator cuff repair, augmentation of subscapularis peel repair, dynamic anterior stabilization, anterior capsule reconstruction, post-stroke stabilization, and superior capsular reconstruction. Some of these applications have been described meticulously in technical notes and case reports, whereas others may require additional research to confirm clinical benefit and efficacy.

CONCLUSION

This review examines the role of the LHBT as a source of local autograft, with biological and biomechanical properties, in aiding outcomes of complex primary and revision shoulder surgery procedures.

Public Interest in Shoulder Platelet-Rich Plasma Injections Is Increasing: A 10-Year Google Trends Analysis

Purpose

To quantify and analyze public interest trends in platelet-rich plasma (PRP) therapy for shoulder pathology between 2011 and 2020 using Google Trends data.

Methods

Google Trends data were queried for online search data ranging from January 2011 to December 2020. Various combinations of terms related to PRP and shoulder pathology were queried. Terms related to corticosteroid therapy in association with shoulder pathology were also generated for comparative analysis. Analyses were performed regarding trends in online search volumes.

Results

Linear models were generated to evaluated trends in the volume of online searches for PRP and corticosteroid therapy for shoulder pathology. For both the PRP and steroid groups, linear models showed a statistically significant increase in search volume for the period studied (P < .001). The PRP group showed a significantly greater growth rate than the steroid group (P < .001). There were no statistically significant differences in online search volume when compared between different geographic and socioeconomic locations.

Conclusions

This study indicates consistently increasing public interest in PRP injections in the shoulder. The rate of online search volume growth of PRP is significantly greater than that of corticosteroid injections for the period studied.

Clinical Relevance

Awareness of patient perceptions has value in informing shared decision making, aligning patient expectations, and guiding areas of future research. Each of these has an impact on patient care. Being aware of patient interest and expectations is particularly important in areas with controversial or emerging research.

The Number of Surgeons Using Superior Capsular Reconstruction for Rotator Cuff Repair Is Declining

Purpose

To investigate surgeon preferences for graft use, including biologic augmentation and superior capsular reconstruction (SCR) associated with surgical treatment of rotator cuff repair (RCR).

Methods

A 26-question survey was completed by arthroscopic shoulder surgeons. Surgeon demographics were evaluated. Surgeons were queried about shoulder arthroscopic graft use and rationale then responses were analyzed based on demographics.

Results

In total, 260 surgeons completed the survey. Fifty-one percent of surgeons reported a decrease in the volume of SCR use in the past 5 years. Less than 3% of surgeons used SCR in >90% of irreparable RCR cases, compared with 38% using SCR in <10% of irreparable cases (P < .05). Surgeons performing >100 RCR annually (42%; P < .05) and those employed in the hospital setting (44%; P < .05) reported an overall increase in the use of SCR. More international surgeons (67%) decreased their use of SCR compared with U.S. surgeons (44%; P < .05). In contrast, bioinductive graft use is generally on the rise, with 48% of surgeons reporting increased use since first use, although used in <10% of cases by 54% of surgeons. Sixty-eight percent of surgeons performing >100 RCRs annually used bioinductive grafts (P < .05). Fewer international surgeons (30%) performed biologic augmentation (P < .05). Suboptimal published outcomes (40%) and no perceived patient benefit (40%) were most cited for decreased SCR use. Surgeons reporting increased use cited improved personal patient outcomes (72%).

Conclusions

Arthroscopic surgeons report decrease in volume of SCR use in the past 5 years. Surgeon's personal experience of patient outcome and suboptimal published results were the strongest factors impacting decision-making. In contrast, bioinductive graft use is increasing. However, most surgeons use these grafts in a relatively small percentage of cases.

Clinical Relevance

Evaluation of scientific data, personal experience, and influences on surgical practice will give a comprehensive understanding of current RCR practices.

Rotator Cuff Repair With Patch Augmentation: What Do We Know?

BACKGROUND

Repair of massive rotator cuff tears remains a challenging process with mixed success. There is a growing interest in the use of patches to augment the repair construct and the potential to enhance the strength, healing, and associated clinical outcomes. Such patches may be synthetic, xenograft, or autograft/allograft, and a variety of techniques have been tried to biologically enhance their integration and performance. The materials used are rapidly advancing, as is our understanding of their effects on rotator cuff tissue. This article aims to evaluate what we currently know about patch augmentation through a comprehensive review of the available literature.

METHODS

We explore the results of existing clinical trials for each graft type, new manufacturing methods, novel techniques for biological enhancement, and the histological and biomechanical impact of patch augmentation.

RESULTS

There are promising results in short-term studies, which suggest that patch augmentation has great potential to improve the success rate. In particular, this appears to be true for human dermal allograft, while porcine dermal grafts and some synthetic grafts have also had promising results.

CONCLUSION

However, there remains a need for high-quality, prospective clinical trials directly comparing each type of graft and the effect that they have on the clinical and radiological outcomes of rotator cuff repair.

Functional and radiologic results of the crimson duvet procedure in rotator cuff treatment: a randomized controlled clinical trial

BACKGROUND

Rotator cuff tears are one of the more frequent pathologies of the shoulder. Arthroscopic techniques and biologic augmentation have been developed to improve the rate and quality of healing. The crimson duvet procedure (CDP) theoretically provides mesenchymal stem cells through microfracture treatment of the footprint. The aim of this research was to evaluate the effect of CDP in patients who had undergone arthroscopic surgery for complete rotator cuff repair.

METHODS

A prospective randomized clinical trial was performed in a total of 123 patients, consisting of 59 women and 64 men, with a mean age of 58 years. We included patients with a clinical and radiologic diagnosis of a complete rotator cuff tear. All patients were treated with arthroscopic rotator cuff repair. In group 1, the surface of the footprint was débrided; in group 2, the footprint underwent microfracture. The primary outcome was the nonhealing rate, which was detected by magnetic resonance imaging (MRI) or ultrasonography, and the secondary outcome was the functional result. A Sugaya classification of I to III was considered to indicate healing. For clinical evaluation, the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) and Constant scores were evaluated, along with the range of motion. The functional evaluation was performed preoperatively and at 6 months and 1 year postoperatively. The radiologic (MRI or ultrasonography) evaluation was performed at 6 months. Neither the patients nor the radiologists and physical therapists who performed the postoperative evaluations were informed of the random selection.

RESULTS

We observed a healing rate of 85.11% in the control group and 93.7% in the CDP group, which was not significant (P = .19). However, a significant improvement in function was observed in all patients. The ASES score improved from 68.9 (SD 13.8) preoperatively to 92.2 at 6 months and to 96.4 (SD 6.2) at 12 months (P < .05), but no difference was observed between the groups. A similar level of improvement was observed in the Constant score.

CONCLUSION

The arthroscopic repair of complete rotator cuff tears presents good and excellent clinical results in most patients. Nevertheless, nonhealing occurs at a rate that depends mainly on the age of the patient and the size of the tear. The addition of CDP did not improve the functional results or the healing rate.

Leukocyte-Rich and Leukocyte-Poor Platelet-Rich Plasma in Rotator Cuff Repair: A Meta-analysis

To systematically review of randomized controlled trials(RCTs) to compared the effects of leukocyte-rich and leukocyte-poor platelet-rich plasma in arthroscopic rotator cuff repair. Two independent reviewers comprehensively searched PubMed, Embase, and Cochrane library databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Comparison of leukocyte-rich platelet-rich plasma or leukocyte-poor platelet-rich plasma in rotator cuff repair in a level I RCTs. Methodological quality assessment was carried out using Cochrane Review Manager 5.3 software. P<0.05 was considered statistically significant. Nine RCTs with 540 patients were included in this review. Meta-analysis showed that leukocyte-poor platelet-rich plasma in significantly reduced retear rate in rotator cuff repair [RR=0.56 95%CI (0.42,0.75); P＜0.05), and in clinical results, the constant score [MD=3.67, 95%CI (1.62,5.73); P=0.0005], UCLA score [MD=1.60, 95%CI (0.79,2.42); P=0.0001], ASES score [MD=2.16, 95%CI(0.12,4.20);P=0.04] were significantly improved. There was a significant result in favor of PRP for the Constant score [MD=-1.24, 95%CI(-1.50,-0.99); P＜0.00001], while SST scores were not significantly different among all groups [MD=0.21, 95%CI(-0.21,0.64); P=0.32]. In conclusion, leukocyte-poor platelet-rich plasma can improved the clinical function and reduced retear rate in arthroscopic rotator cuff repair. In contrast, the efficacy of leukocyte-rich platelet-rich plasma was not significantly improved with the exception of VAS score.

Autograft Long Head Biceps Tendon Can Be Used as a Scaffold for Biologically Augmenting Rotator Cuff Repairs

PURPOSE

We create a viable, mechanically expanded autograft long head biceps tendon (LHBT) scaffold for biologically augmenting the repair of torn rotator cuffs.

METHODS

The proximal aspect of the tenotomized LHBTs was harvested from patients during rotator cuff repair surgery and was mechanically formed into porous scaffolds using a surgical graft expander. LHBT scaffolds were evaluated for change in area, tensile properties, and tenocyte viability before and after expansion. The ability of endogenous tenocytes derived from the LHBT scaffold to promote tenogenic differentiation of human adipose-derived mesenchymal stromal cells (ADMSCs) was also determined.

RESULTS

Autograft LHBTs were successfully expanded using a modified surgical graft expander to create a porous scaffold containing viable resident tenoctyes from patients undergoing rotator cuff repair. LHBT scaffolds had significantly increased area (length: 24.91 mm [13.91, 35.90] × width: 22.69 mm [1.87, 34.50]; P = .011) compared with the native LHBT tendon (length: 27.16 mm [2.70, 33.62] × width: 6.68 mm [5.62, 7.74]). The structural properties of the autograft were altered, including the ultimate tensile strength (LHBT scaffold: .56 MPa [.06, 1.06] vs. native LHBT: 2.35 MPa [1.36, 3.33]; P = .002) and tensile modulus (LHBT scaffold: 4.72 MPa [-.80, 1.24] versus native LHBT: 37.17 MPa [24.56, 49.78]; P = .001). There was also a reduction in resident tenocyte percent viability (LHBT scaffold: 38.52% [17.94, 59.09] vs. native LHBT: 68.87% [63.67, 74.37]; P =.004). Tenocytes derived from the LHBT scaffold produced soluble signals that initiated ADMSC differentiation into an immature tenocyte-like phenotype, as indicated by an 8.7× increase in scleraxis (P = .040) and a 3.6× increase in collagen type III mRNA expression (P = .050) compared with undifferentiated ADMSC controls.

CONCLUSIONS

The ability to produce a viable autologous scaffold from the proximal biceps tendon having dimensions, porosity, mechanical characteristics, native ECM components, and viable tenocytes that produce bioactive signals conducive to supporting the biologic augmentation of rotator cuff repair surgery has been demonstrated.

CLINICAL RELEVANCE

This biologically active construct may help to improve the quality of healing and regeneration at the repair site of rotator cuff tears, especially those at high risk for retear.

Systematic Review of Platelet-Rich Plasma for Rotator Cuff Repair: Are We Adhering to the Minimum Information for Studies Evaluating Biologics in Orthopaedics?

Background

The therapeutic efficacy of orthobiologic therapies for rotator cuff repair is difficult to evaluate owing to reporting inconsistences. In response, the Minimum Information for Studies Evaluating Biologics in Orthopaedics (MIBO) guidelines were developed to ensure standard reporting on orthobiologic therapies.

Purpose

To systematically review clinical studies evaluating platelet-rich plasma (PRP) for full-thickness rotator cuff repair and adherence to MIBO guidelines.

Study Design

Scoping review; Level of evidence, 4.

Methods

A search was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using PubMed, EMBASE, and the Cochrane Library databases. Inclusion criteria were clinical studies reporting on rotator cuff tears (≥1 cm) surgically repaired with PRP. Patient demographics, biologic intervention, and adherence to the MIBO guidelines were systematically reviewed.

Results

A total of 19 studies (1005 patients) were included in this review. Across all studies, 58.5% of the MIBO checklist items for PRP were reported. Out of 47 checklist items, 19 were reported in over 85% of studies, whereas 22 were reported in less than half of studies. Details of whole-blood processing and characteristics, as well as PRP processing and characteristics, were reported inconsistently, and no study provided adequate information to enable the precise replication of preparation protocols for PRP.

Conclusion

This systematic review highlights the current reporting deficiencies within the scientific literature of important variables for evaluating PRP for full-thickness rotator cuff repair. There was widespread variability among published studies that evaluate PRP for this application and, more specifically, studies were limited by inconsistent universal reporting of whole-blood and PRP processing and postprocessing characteristics. To improve our understanding of biologic efficacy and to promote repeatability, stricter adherence to the MIBO guidelines is necessary. We propose that the checklist limitations be addressed and that modification of the MIBO guidelines be considered to improve the reporting of individual components within certain categories.

The role of MicroRNAs in tendon injury, repair, and related tissue engineering

Tendon injuries are one of the most common musculoskeletal disorders that cause considerable morbidity and significantly compromise the patients' quality of life. The innate limited regenerative capacity of tendon poses a substantial treating challenge for clinicians. MicroRNAs (miRNAs) are a family of small non-coding RNAs that play a vital role in orchestrating many biological processes through post-transcriptional regulation. Increasing evidence reveals that miRNA-based therapeutics may serve as an innovative strategy for the treatment of tendon pathologies. In this review, we briefly present miRNA biogenesis, the role of miRNAs in tendon cell biology and their involvement in tendon injuries, followed by a summary of current miRNA-based approaches in tendon tissue engineering with a special focus on attenuating post-injury fibrosis. Next, we discuss the advantages of miRNA-functionalized scaffolds in achieving sustained and localized miRNA administration to minimize off-target effects, and thus hoping to inspire the development of effective miRNA delivery platforms specifically for tendon tissue engineering. We envision that advancement in miRNA-based therapeutics will herald a new era of tendon tissue engineering and pave a way for clinical translation for the treatments of tendon disorders.

Mesenchymal stem cell-derived exosomes: therapeutic implications for rotator cuff injury

Rotator cuff injuries are a common clinical condition of the shoulder joint. Surgery that involves reattaching the torn tendon to its humeral head bony attachment has a somewhat lower success rate. The scar tissue formed during healing of the rotator cuff leads to poor tendon-related mechanical properties. To promote healing, a range of genetic interventions, as well as cell transplantation, and many other techniques have been explored. In recent years, the therapeutic promise of mesenchymal stem cells (MSCs) has been well documented in animal and clinical studies. Some data have suggested that MSCs can promote angiogenesis, reduce inflammation and cell proliferation and increase collagen deposition. These functions are likely paracrine effects of MSCs, particularly mediated through exosomes. Here, we review the use of MSCs-related exosomes in tissues and organs. We also discuss their potential utility for treating rotator cuff injuries, and explore the underlying mechanisms of their effects.

Footprint preparation with nanofractures in a supraspinatus repair cuts in half the retear rate at 1-year follow-up. A randomized controlled trial

PURPOSE

To evaluate if adding nanofractures to the footprint of a supraspinatus tear repair would have any effect in the outcomes at one-year follow-up.

METHODS

Multicentric, triple-blinded, randomized trial with 12-months follow-up. Subjects with isolated symptomatic reparable supraspinatus tears smaller than 3 cm and without grade 4 fatty infiltration were included. These were randomized to two groups: In the Control group an arthroscopic supraspinatus repair was performed; in the Nanofracture group the footprint was additionally prepared with nanofractures (1 mm wide, 9 mm deep microfractures). Clinical evaluation was done with Constant score, EQ-5D-3L, and Brief Pain Inventory. The primary outcome was the retear rate in MRI at 12-months follow-up. Secondary outcomes were: characteristics of the retear (at the footprint or at the musculotendinous junction) and clinical outcomes.

RESULTS

Seventy-one subjects were randomized. Two were lost to follow-up, leaving 69 participants available for assessment at 12-months follow-up (33 in the Control group and 36 in the Nanofracture Group). The Nanofracture group had lower retear rates than the Control group (7/36 [19.4%] vs 14/33 [42.4%], differences significant, p = 0.038). Retear rates at the musculotendinous junction were similar but the Nanofracture group had better tendon healing rates to the bone (34/36 [94.4%] vs. 24/33 [66.71%], p = 0.014). Clinically both groups had significant improvements, but no differences were found between groups.

CONCLUSION

Adding nanofractures at the footprint during an isolated supraspinatus repair lowers in half the retear rate at 12-months follow-up. This is due to improved healing at the footprint.

LEVEL OF EVIDENCE

Level I.

Current Biological Strategies to Enhance Surgical Treatment for Rotator Cuff Repair

Rotator cuff tear is one of the most common shoulder problems encountered by orthopedic surgeons. Due to the slow healing process and high retear rate, rotator cuff tear has distressed millions of people all around the world every year, especially for the elderly and active athletes. This disease significantly impairs patients' motor ability and reduces their quality of life. Besides conservative treatment, open and arthroscopic surgery contributes a lot to accelerate the healing process of rotator cuff tear. Currently, there are many emerging novel treatment methods to promote rotator cuff repair. A variety of biological stimulus has been utilized in clinical practice. Among them, platelet-rich plasma, growth factors, stem cells, and exosomes are the most popular biologics in laboratory research and clinical trials. This review will focus on the biologics of bioaugmentation methods for rotator cuff repair and tendon healing, including platelet-rich plasma, growth factors, exosomes and stem cells, etc. Relevant studies are summarized in this review and future research perspectives are introduced.

Microfragmented Adipose Tissue With Adjuvant Platelet-Rich Plasma Combination Therapy for Partial-Thickness Supraspinatus Tear

A 50-year-old male presented with acute, sharp, right shoulder pain. Ultrasound of the right shoulder revealed a partial thickness tear of the supraspinatus. After conservative management failed to provide any relief, he was treated with microfragmented adipose tissue (MFAT) injection followed by platelet-rich plasma (PRP) at 14 weeks. At the 28-week follow-up, he showed significant improvement in pain and mobility with a resolution of the tear on ultrasound. While PRP has been shown to confer some protection against retears, very few studies have investigated the efficacy of MFAT use in rotator cuff pathology. In this case, we used a combination of MFAT and PRP to successfully treat a partial thickness supraspinatus tear. These agents may function in a synergistic manner, with MFAT providing a cell scaffold and PRP modulating the cellular environment to optimize healing. Further studies are needed to better understand the mechanism of this treatment modality in treating similar conditions.

Hip abductor tendon tears: where are we now?

Hip abductor tendon tear is a difficult problem to manage. The hip abductor mechanism is made up of the gluteus medius and minimus muscles, both of which contribute to stabilising the pelvis through the gait cycle. Tears of these tendons are likely due to iatrogenic injury during arthroplasty and chronic degenerative tendinopathy. Ultrasound and magnetic resonance imaging have provided limited clues regarding the pattern of disease and further work is required to clarify both the macro and microscopic pattern of disease. While surgery has been attempted over the last 2 decades, the outcomes are variable and the lack of high-quality studies have limited the uptake of surgical repair. Hip abductor tendon tears share many features with rotator cuff tears, hence, innovations in surgical techniques, materials and biologics may apply to both pathologies.

Bony Ingrowth of Coil-Type Open-Architecture Anchors Compared With Screw-Type PEEK Anchors for the Medial Row in Rotator Cuff Repair: A Randomized Controlled Trial

PURPOSE

To evaluate outcomes of screw-type and coil-type open-architecture suture anchors with respect to bony ingrowth, release of biological markers, and patient-reported outcome measures when used in rotator cuff repair (RCR).

METHODS

Forty patients undergoing arthroscopic RCR for full-thickness rotator cuff tears were enrolled and prospectively randomized to receive a screw-type (19 patients) or coil-type (21 patients) suture anchor for the medial row during repair. All repairs used a transosseous-equivalent configuration with footprint anchors laterally. Marrow elements released during surgery were evaluated for 9 cytokine markers (insulin-like growth factor 1, fibroblast growth factor 2, bone morphogenetic proteins 7 and 2, platelet-derived growth factors AA and BB, epidermal growth factor, transforming growth factor beta1, and vascular endothelial growth factor). Postoperative computed tomography scans were performed at 6 months. Range of motion, strength, and validated patient-reported outcome measures (Simple Shoulder Test, Single Assessment Numeric Evaluation, visual analog scale, and American Shoulder and Elbow Surgeons scores) were gathered before the operation and at 6 months and 1 year postoperatively.

RESULTS

Bone mineral density surrounding the coil-type anchor was significantly greater than that surrounding the screw-type anchor (P = .005). Bone mineral density values within the coil-type and screw-type anchors were comparable (P = .527); however, a larger amount of total bone mineral mass (in milligrams) was shown within the coil-type anchor owing to its larger volume (P < .01). Marrow elements released at the repair site were similar between groups (P > .05). Postoperatively, no statistically significant difference was found between groups for clinical outcome measures at 6 months or 1 year. Retear and complication rates were similar between groups (P > .05).

CONCLUSIONS

Both the coil-type and screw-type anchors can be reliably used for RCR and produce similar clinical outcomes. The coil-type anchor resulted in superior bony growth surrounding the anchor and a larger total bone mineral mass within the anchor owing to its larger volume.

LEVEL OF EVIDENCE

Level II, randomized prospective comparative study.

Editorial Commentary: Innovations in Anchor Design-Are Patients Really Benefiting?

Vented open-architecture suture anchors provide theoretical benefits over traditional screw-in solid anchors to include improved osseous ingrowth, elution of marrow elements to enhance biology at the repair site, and easier revision because of reduced anchor material. However, there is no evidence that open-architecture anchors result in improvements in patient-reported outcomes or early cytokine and marrow element release into the subacromial space compared with traditional screw-in solid anchors. Although innovation and evaluation of new technologies are paramount to surgical progress, decisions on implant use should be based on factors including cost, impact on revision, and surgeon familiarity because frequently, clinical differences based on patient-reported outcomes are not appreciated between anchor types or designs.

The role of biologic agents in the management of common shoulder pathologies: current state and future directions

The field of orthopedic surgery has seen a rapid increase in the use of various biologic agents for the treatment of common musculoskeletal injuries. Most biologic agents attempt to harness or mimic naturally occurring growth factors, cytokines, and anti-inflammatory mediators to improve tissue healing and recovery. The most commonly used biologic agents are platelet-rich plasma and cells derived from bone marrow aspirate and adipose tissue. These agents have become increasingly popular despite a relative dearth of clinical data to support their use. Much confusion exists among patients and physicians in determining the role of these agents in treating common shoulder pathologies, such as glenohumeral osteoarthritis, rotator cuff tears, and tendinopathy. This article reviews the basic science and clinical evidence for the most commonly used biologic agents in the management of common shoulder pathology.

No healing improvement after rotator cuff reconstruction augmented with an autologous periosteal flap

PURPOSE

To show descriptive clinical and magnetic resonance (MR) imaging results after an additional periosteal flap augmentation in mini-open rotator cuff reconstruction and to evaluate potential healing improvement at long-term follow-up.

METHODS

Twenty-three patients with degenerative rotator cuff tears were followed after receiving a mini-open single-row repair with a subtendinous periosteal flap augmentation. Data were collected preoperatively, after 12 months and after 11 years. Clinical examination, simple shoulder test (SST), Constant-Murley Score (CS), ultrasonography examination and 3T MR imaging were performed.

RESULTS

Out of 23 patients, 20 were available for short-term and 19 for final follow-up at a median of 11.5 years (range 10.4-13.0). Questions answered with "yes" in SST improved from baseline 5.0 (range 1.0-8.0) to short 10.5 (range 8.0-12.0) and final follow-up 12.0 (range 7.0-12.0). CS improved from 53.5 (range 25.0-66.0) to 80.8 (range 75.9-89.3) and finally to 79.8 points (range 42.3-95.4). Improvement was highly significant (p < 0.05). Severe retears were found in 9/19 patients. Ossifications along the refixed tendon were noticed in 8/19 cases. Ossifications did not correlate with clinical outcome. At final follow-up, patients with retears seemed likely to have lower strength values in CS (mean ± SD) than patients without retears (7.3 ± 4.1 vs. 12.8 ± 5.3; p < 0.05).

CONCLUSION

No positive effect on improving healing response in rotator cuff refixation with a periosteal flap augmentation could be found. Retear rate is comparable to that of conventional rotator cuff refixation in the published literature. Ossifications along the tendon, without negatively affecting the clinical outcome, were seen. This invasive technique cannot be advised and should not be used anymore.

LEVEL OF EVIDENCE

IV.

Efficacy of Platelet-Rich Plasma for the Treatment of Interstitial Supraspinatus Tears: A Double-Blinded, Randomized Controlled Trial

BACKGROUND

The benefits of platelet-rich plasma (PRP) for the treatment of rotator cuff tears remain inconclusive, as it is administered either as an adjuvant to surgical repair or as a primary infiltration without targeting the index lesion, which could dilute its effect.

PURPOSE

To determine whether PRP infiltrations are superior to saline solution infiltrations (placebo) at improving healing, pain, and function when injected under ultrasound guidance within isolated interstitial supraspinatus tears.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

In this single-center, double-blinded, randomized controlled trial, 80 adults with symptomatic isolated interstitial tears of the supraspinatus, confirmed by magnetic resonance arthrography, were randomized to PRP or saline injections. Each patient received 2 injections with a 1-month interval. The primary outcome was the change in lesion volume, calculated on magnetic resonance arthrography, at 7 months. The secondary outcomes were improvements in shoulder pain and the Single Assessment Numerical Evaluation (SANE) score at >12 months.

RESULTS

Preoperative patient characteristics did not differ between the 2 groups. At 7 months, there were no significant differences between the PRP and control groups in terms of a decrease in lesion size (-0.3 ± 23.6 mm³ vs -8.1 ± 84.7 mm³, respectively; P = .175); reduction of pain on a visual analog scale (VAS) (-2.3 ± 3.0 vs -2.0 ± 3.0, respectively; P = .586); and improvement in SANE (16.7 ± 20.0 vs 14.9 ± 29.0, respectively; P = .650), Constant (8.6 ± 13.0 vs 10.7 ± 19.0, respectively; P = .596), and American Shoulder and Elbow Surgeons (19.5 ± 20.0 vs 21.9 ± 28.0, respectively; P = .665) scores. At >12 months, there were no significant differences between the PRP and control groups in terms of a reduction of pain on a VAS (-3.3 ± 2.6 vs -2.3 ± 3.2, respectively; P = .087) or improvement in the SANE score (24.4 ± 27.5 vs 23.4 ± 24.9, respectively; P = .846). At 19.5 ± 5.3 months, the incidence of adverse effects (pain >48 hours, frozen shoulder, extension of lesion) was significantly higher in the PRP group than the control group (54% vs 26%, respectively; P = .020).

CONCLUSION

PRP injections within interstitial supraspinatus tears did not improve tendon healing or clinical scores compared with saline injections and were associated with more adverse events.

REGISTRATION

NCT02672085 (ClinicalTrials.gov identifier).

Graft use in the treatment of large and massive rotator cuff tears: an overview of techniques and modes of failure with MRI correlation

Despite technical advances, repair of large or massive rotator cuff tears continues to demonstrate a relatively high rate of failure. Rotator cuff repair or superior capsular reconstruction (SCR) using a variety of commercially available grafts provides a promising option in patients with tears that may be at high risk for failure or otherwise considered irreparable. There are three major graft constructs that exist when utilizing graft in rotator cuff repair or reconstruction: augmentation at the rotator cuff footprint, bridging, and SCR. Each construct has a unique appearance when evaluated using postoperative magnetic resonance imaging (MRI), and each construct has unique sites that are predisposed to failure. Understanding the basic principles of these constructs can help the radiologist better evaluate the postoperative MRI appearance of these increasingly utilized procedures.

Platelet-rich plasma: myth or reality?

Platelet-rich plasma (PRP) is a preparation for therapeutic purposes that is increasingly accepted for various musculoskeletal disorders, due to its theoretical potential to repair tissues with poor healing capacity. Several randomised clinical trials have investigated the capacity of PRP to repair tendons, ligaments, muscles and cartilage, and to date there is level 1a evidence to support its use for lateral epicondylitis, osteoarthritis of the knee, plantar fasciitis and rotator cuff tendinopathy; and level 1b for patellar tendinopathy and osteoarthritis of the hip. Retrospective cohort studies and case series describe promising results with PRP for treating other musculoskeletal disorders. Since its side effects are fewer than those of the control groups, the treatment is considered practically harmless and is being increasingly used. Further randomised clinical trials are necessary to establish future indications, and to confirm effectiveness and safety.

Platelet-rich plasma and the shoulder: clinical indications and outcomes

PURPOSE OF REVIEW

The orthopedic community has seen a rapid rise in the clinical use of platelet-rich plasma (PRP) in the management of shoulder pathologies over the past decade. The purpose of this paper is to review the current literature regarding the indications and outcomes of PRP for the surgical and non-surgical management of common shoulder pathologies, including rotator cuff tears.

RECENT FINDINGS

Multiple studies have been published recently regarding the use of PRP for the operative and non-operative treatment of rotator cuff tears. There has been less research published on the use of PRP in the management of other conditions of the shoulder. Despite attempts to standardize and classify PRP formulations, there remains great variation in the inter- and intra-subjection composition, preparation, and administration techniques of PRP, limiting the conclusions that can be drawn regarding the utility and effectiveness of this biologic treatment as reported by Mazzocca et al. (J Bone Joint Surg Am. 94(4):308-16, 2012). Recent literature has shown equivocal to minor benefit of PRP use for shoulder pain, function, and healing. While few complications have been reported and PRP administration appears to carry little risk to the patient, the body of literature is currently inconclusive regarding the clinical benefit and cost-effectiveness of PRP in the treatment of shoulder pathology. As for PRP use specifically as an adjunct to surgical rotator cuff repairs, there is no clear consensus on its effectiveness in either clinical or structural outcomes. To further delineate the efficacy of PRP for shoulder pathology, it is essential that more double-blinded, randomized controlled investigations with large sample sizes and standardized PRP preparations be performed.

Biologics and stem cell-based therapies for rotator cuff repair

The rotator cuff is composed of several distinct muscles and tendons that function in concert to coordinate shoulder motion. Injuries to these tendons frequently result in permanent dysfunction and persistent pain. Despite considerable advances in operation techniques, surgical repair alone still does not fully restore rotator cuff function. This review focuses on recent research in the use of biologics and stem cell-based therapies to augment repair, highlighting promising avenues for future work and remaining challenges. While a number of animal models are used for rotator cuff studies, the anatomy of the rotator cuff varies dramatically between species. Since the rodent rotator cuff shares the most anatomical features with the human, this review will focus primarily on rodent models to enable consistent interpretation of outcome measures.