Biologic Treatments for Sports Injuries II Think Tank-Current Concepts, Future Research, and Barriers to Advancement, Part 2: Rotator Cuff

Leukocyte-Poor Platelet-Rich Plasma as an Adjuvant to Arthroscopic Rotator Cuff Repair Reduces the Retear Rate But Does Not Improve Functional Outcomes: A Double-Blind Randomized Controlled Trial

BACKGROUND

Whether the use of PRP as an adjuvant of rotator cuff repairs leads to improved tendon healing and better functional outcomes remains unclear in clinical evidence.

PURPOSE

The main purpose of this study was to assess whether the use of leukocyte-poor platelet-rich plasma (LP-PRP) as an adjuvant to arthroscopic rotator cuff repair (ARCR) decreases the rate of retears compared with a control group. The secondary objective was to analyze whether LP-PRP improves patient-reported outcomes.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

This was a double-blind randomized controlled trial at a single center. A consecutive series of 96 patients with rotator cuff tears <3 cm were enrolled and randomly allocated to the control group (double-row suture-bridge ARCR alone [n = 48]) and the PRP group (double-row suture-bridge repair, followed by 1 LP-PRP injection during surgery [n = 48]). The visual analog scale (VAS) for pain, the American Shoulder and Elbow Surgeons (ASES) score, the Single Assessment Numeric Evaluation (SANE), and the Pittsburgh Sleep Quality Index (PSQI) were administered preoperatively and at 6- and 12-month follow-up. Magnetic resonance imaging (MRI) was performed to evaluate tendon integrity at 6-month follow-up. Both patients and assessors were blinded to the intervention received during surgery.

RESULTS

The mean patient age was 56.1 ± 2.98 years. Of the 96 patients, 90 had MRI performed at 6 months after surgery (94% radiological follow-up). The retear rate in the PRP group was 15.2% (7/46 [95% CI, 6%-28%]), which was lower than that in the control group of 34.1% (15/44 [95% CI, 20%-49%]) (P = .037). Therefore, the risk ratio of ruptures in patients exposed to LP-PRP was 0.44 (95% CI, 0.2-0.9; P = .037). Overall, the ASES, VAS, SANE, and PSQI scores showed a statistical improvement after surgery (P < .001). There were no significant differences in functional scores between the groups. Most of the patients exceeded the minimal clinically important difference for the ASES, SANE, and VAS without significant differences between the groups.

CONCLUSION

In patients with rotator cuff tears <3 cm undergoing double-row suture-bridge repair, a 5-mL dose of LP-PRP injected at the tendon-bone interface significantly reduced the retear rate. However, the use of LP-PRP in terms of postoperative pain and patient-reported outcomes failed to show clinically meaningful effects.

REGISTRATION

NCT04703998 (ClinicalTrials.gov identifier).

Most Publications Regarding Platelet-Rich Plasma Use in the Knee Are From Asia, Investigate Injection for Osteoarthritis, and Show Outcome Improvement: A Scoping Review

PURPOSE

To evaluate and synthesize the available literature related to platelet-rich plasma (PRP) treatment of knee pathologies and to provide recommendations to inform future research in the field.

METHODS

PubMed, CINAHL, and Scopus databases were queried on October 6, 2023. All identified citations were collated and uploaded into Covidence for screening and data extraction. Studies were included if they were human studies published in English with adult cohorts that received PRP as a procedural injection or surgical augmentation for knee pathologies with patient-reported outcome measures (PROMs) and level of evidence Levels I-IV.

RESULTS

Our search yielded 2,615 studies, of which 155 studies from 2006 to 2023 met the inclusion criteria. Median follow-up was 9 months (±11.2 months). Most studies (75.5%) characterized the leukocyte content of PRP, although most studies (86%) did not use a comprehensive classification scheme. In addition, most studies were from Asia (50%) and Europe (32%) and were from a single center (96%). In terms of treatment, 74% of studies examined PRP as a procedural injection, whereas 26% examined PRP as an augmentation. Most studies (68%) examined treatment of knee osteoarthritis. Many studies (83%) documented significant improvements in PROMs, including 93% of Level III/IV evidence studies and 72% of Level I/II evidence studies, although most studies (70%) failed to include minimal clinically important difference values. The visual analog scale was the most-used PROM (58% of studies), whereas the Short Form Health Survey 36-item was the least-used PROM (5% of studies).

CONCLUSIONS

Most published investigations of knee PRP are performed in Asia, investigate procedural injection for osteoarthritis, and show significant outcome improvements. In addition, this review highlights the need for better classification of PRP formulations.

LEVEL OF EVIDENCE

Level IV, scoping Review of level I-IV studies.

An Update on Orthobiologics: Cautious Optimism

Orthobiologics are rapidly growing in use given their potential to augment healing for multiple musculoskeletal conditions. Orthobiologics consist of a variety of treatments including platelet-rich plasma and stem cells that provide conceptual appeal in providing local delivery of growth factors and inflammation modulation. The lack of standardization in nomenclature and applications within the literature has led to a paucity of high-quality evidence to support their frequent use. The purpose of this review was to describe the current landscape of orthobiologics and the most recent evidence regarding their use.

Bone channeling in arthroscopic rotator cuff repair: a systematic review and meta-analysis of level I studies

BACKGROUND

There is ongoing controversy regarding the effect of bone channeling in arthroscopic rotator cuff repair. Since the most recent systematic reviews in 2019, several large high-level trials have been completed. This study assessed all available level I randomized controlled trials (RCTs) that compared arthroscopic rotator cuff repair with and without bone marrow channeling.

METHODS

A systematic search of the Ovid MEDLINE, Embase, and Cochrane Library databases was conducted through mid January 2023. Two reviewers performed screening of studies meeting the eligibility criteria: English-language RCTs in patients aged ≥18 years comparing arthroscopic rotator cuff repair of full-thickness tears with and without bone marrow channeling (channeling group and control group, respectively). Functional scores, pain, healing rates, and reoperations were reviewed using pooled analysis where appropriate. The methodologic quality of included studies was assessed using the Cochrane risk-of-bias tool and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

RESULTS

A total of 6 randomized studies (N = 593) met the inclusion criteria. Pooled analysis of all 6 studies showed no significant mean difference in function (1.32; 95% confidence interval [CI], -0.63 to 3.26), as measured by the Constant-Murley score. Retear rates were also not statistically different between groups (risk ratio, 0.99; 95% CI, 0.57 to 1.71), with pooled retear rates of 19.6% (48 of 245) with channeling and 19.8% (51 of 257) without. The other outcomes of interest were only available for analysis in a subset of studies. There were no standardized mean differences in pain (0.09; 95% CI, -0.18 to 0.36), and there were similar reoperation rates (risk ratio, 1.19; 95% CI, 0.43 to 3.34) in the channeling and control groups. For the included studies, the overall quality of evidence by outcome was judged to be moderate (function, pain, and reoperations) or low (retear rates), mainly owing to risk of bias (all outcomes) and inconsistency (retear rates).

CONCLUSION

The results of this study refute the findings of prior systematic reviews that showed that channeling reduces the retear rate when combined with arthroscopic rotator cuff repair. This meta-analysis of level I evidence, including recent larger RCTs, demonstrates that bone marrow stimulation in the setting of primary arthroscopic rotator cuff repair has no significant effect on functional outcomes, healing, pain, or reoperation rates.

Orthobiologics: a review

PURPOSE

The use of biologic materials in orthopaedics (orthobiologics) has gained significant attention over the past years. To enhance the body of the related literature, this review article is aimed at summarizing these novel biologic therapies in orthopaedics and at discussing their multiple clinical implementations and outcomes.

METHODS

This review of the literature presents the methods, clinical applications, impact, cost-effectiveness, and outcomes, as well as the current indications and future perspectives of orthobiologics, namely, platelet-rich plasma, mesenchymal stem cells, bone marrow aspirate concentrate, growth factors, and tissue engineering.

RESULTS

Currently available studies have used variable methods of research including biologic materials as well as patient populations and outcome measurements, therefore making comparison of studies difficult. Key features for the study and use of orthobiologics include minimal invasiveness, great healing potential, and reasonable cost as a nonoperative treatment option. Their clinical applications have been described for common orthopaedic pathologies such as osteoarthritis, articular cartilage defects, bone defects and fracture nonunions, ligament injuries, and tendinopathies.

CONCLUSIONS

Orthobiologics-based therapies have shown noticeable clinical results at the short- and mid-term. It is crucial that these therapies remain effective and stable in the long term. The optimal design for a successful scaffold remains to be further determined.

Editorial Commentary: Rotator Cuff Repairs Fail at an Alarmingly High Rate During Long-Term Follow-Up: Graft Augmentation and Biologics May Improve Future Outcomes

Rotator cuff repairs (RCR) frequently fail to heal, particularly those with advanced fatty infiltration, supraspinatus and infraspinatus atrophy, narrowed acromiohumeral distance, and large-to-massive tear size. Unfortunately, the longer the follow up, the more sobering the statistics, with some reported retear rates ranging up to 94%. Importantly, recent long-term radiographic assessments after primary RCR reveal direct correlations between failure and patient-reported outcomes, functional deterioration, and ultimately, progression of glenohumeral arthritis and/or frank cuff tear arthropathy. As shoulder surgeons, we must continue to seek out novel approaches to improve tendon to bone healing and recapitulate the native rotator cuff enthesis. In doing so, we hope to engender more sustained subjective and objective results for our patients over time. Investigations are ongoing into several biomechanical and biological or structural adjuncts, from platelet-rich plasma and bone marrow aspirate concentrate to autograft or allograft structural augments. We must continue to push the envelope and refuse to settle for the current reality and alarmingly high failure rates following RCR.

The Quality and Accuracy of Direct-to-Consumer Biologic Marketing for Shoulder Pathology is Poor

Background

The growing role of biologic therapies as adjunct or standalone procedures in orthopedic practice has led to greater levels of direct-to-consumer biologic marketing. The present study aims to assess the quality, accuracy, and readability of online educational resources available to patients regarding biologic therapies for shoulder pathology.

Methods

Eight search terms relevant to shoulder biologic therapies (shoulder + BMAC, Bone Marrow Aspirate Concentrate, PRP, Platelet Rich Plasma, Lipogems, Adipose Tissue, Biologic therapy, and Stem cell therapy) were searched across three separate search engines. The first 25 websites of each search were recorded. Duplicate websites and those not specific to shoulder pathology were excluded. Three evaluators independently assessed quality using an author-derived scoring rubric for a total of 25 possible points and accuracy for a total of 12 possible points. The Flesch-Kincaid readability test was used to quantify reading levels. Websites were further characterized by authorship and the presence of commercial bias.

Results

Of the 600 results from the initial search, 59 met inclusion criteria. The mean quality of the websites was poor, with 7.97 ± 2.3 of 25 points (32%). The mean accuracy was low, with 8.47 ± 1.52 of 12 points (71%). The average reading level was 11.2 ± 1.93, with 32% of websites' reading at greater than 12^th grade reading level. The search terms of “shoulder PRP” and “shoulder Platelet Rich Plasma” yielded the highest quality results (mean = 8.14 ± 2.63). “shoulder Lipogems” and “shoulder Adipose tissue” yielded the most accurate results (mean = 9.25 ± 0.96). “shoulder BMAC” and “shoulder bone marrow aspirate concentrate” were most difficult to read (mean = 12.54 ± 3.73). Sixty-four percent of websites were authored by physicians, hospitals, or medical groups. The accuracy of websites authored by health care professionals was significantly higher than the accuracy of those authored by other industry sources (P = .01). Fifteen percent of websites demonstrated commercial bias.

Discussion

The online resources available to patients seeking information about biologic therapies for the treatment of shoulder pathologies are of very poor quality, moderately poor accuracy, and advanced readability. Providers should caution patients about the reliability of direct-to-consumer biologic marketing for shoulder pathology.

Conclusion

The information available to patients online regarding the diagnosis, evaluation, and treatment of shoulder pathology with biologic therapies is of poor quality and accuracy and difficult readability.

Subacromial Platelet-Rich Plasma Injections Decrease Pain and Improve Functional Outcomes in Patients With Refractory Rotator Cuff Tendinopathy

PURPOSE

The purpose of this study was to evaluate the effect of subacromial platelet-rich plasma (PRP) injections in patients with refractory rotator cuff tendinopathies based on pain improvement, functional outcomes, sleep disturbances, and return to sports to the same level as before the injury.

METHODS

Between March 2019 and October 2019, 50 patients with rotator cuff tendinopathy refractory to conservative treatment were treated with one subacromial PRP injection in our institution. Magnetic resonance imaging was performed in all patients to confirm diagnosis. The visual analog scale (VAS) was used to evaluate pain. Range of motion, the American Shoulder and Elbow Surgeons (ASES) score, and the Constant score were used to assess functional outcomes. Eighty percent of the patients (40 of 50 patients) and 86% of the patients (43 of 50 patients) achieved a clinically significant improvement that exceeded the substantial clinical benefit for the ASES and Constant scores, respectively. The Pittsburgh Sleep Quality Index was used to assess sleep disorders. Return to sports was also evaluated. The mean follow-up was 12 months, and the mean (SD) age was 37.3 (9.3) years.

RESULTS

All mobility parameters evaluated improved significantly after treatment. The VAS, ASES, and Constant scores showed statistical improvement after the injection (P < .001). Sleep disturbances were resolved in 86% of the patients. Of the 32 patients who practiced sports before the injury, 84% returned to sports and 78% returned to the same level. There were no complications associated with the procedure.

CONCLUSIONS

In most patients with refractory rotator cuff tendinopathy, subacromial injections of leukocyte-rich PRP significantly decreased pain, improved functional outcomes, and resolved sleep disturbances. Moreover, most of the athletes returned to sports at the same level they had before the injury.

LEVEL OF EVIDENCE

Level II, prospective cohort study.

Biologics in professional and Olympic sport: a scoping review

AIMS

The aim of this study was to prepare a scoping review to investigate the use of biologic therapies in the treatment of musculoskeletal injuries in professional and Olympic athletes.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for scoping reviews and Arksey and O'Malley frameworks were followed. A three-step search strategy identified relevant published primary and secondary studies, as well as grey literature. The identified studies were screened with criteria for inclusion comprising clinical studies evaluating the use of biologic therapies in professional and Olympic athletes, systematic reviews, consensus statements, and conference proceedings. Data were extracted using a standardized tool to form a descriptive analysis and a thematic summary.

RESULTS

A total of 202 studies were initially identified, and 35 met criteria for the scoping review; 33 (94.3%) were published within the last eight years, and 18 (51.4%) originated from the USA. Platelet rich plasma was the most studied biologic therapy, being evaluated in 33 (94.3%) studies. Ulnar collateral ligament and hamstring injuries were the conditions most studied (nine (25.7%) studies and seven (20.0%) studies, respectively). Athletes most frequently participated in baseball, soccer, and American football. Only two (5.7%) studies were level 1 evidence, with interpretation and comparison between studies limited by the variations in the injury profile, biologic preparations, and rehabilitation protocols.

CONCLUSION

There is diverse use of biologic therapies in the management of musculoskeletal injuries in professional and Olympic athletes. There is currently insufficient high-level evidence to support the widespread use of biologic therapies in athletes. Further research priorities include the development of condition/pathology-specific preparations of biologic therapies, and of outcome measures and imaging modalities sufficiently sensitive to detect differences in outcomes, should they exist. Cite this article: Bone Joint J 2021;103-B(7):1189-1196.

The future of meniscus science: international expert consensus

Purpose

The purpose of this study was to evaluate the main focus areas for research and development for furthering the state of meniscus science in 2021.

Methods

An electronic survey including 10 questions was sent in a blind fashion to the faculty members of the 5^th International Conference on Meniscus Science and Surgery. These faculty served as an expert consensus on the future of research and development areas of meniscus science. Survey responses were analyzed using descriptive statistics and ranking weighted averages were calculated to score survey questions.

Results

Of the 82 faculty, 76 (93%) from 18 different countries completed the survey (84% male, 16% female). The highest ranked future research and development focus areas were meniscus repair, biologics, osteotomy procedures, addressing meniscus extrusion, and the development of new therapies for the prevention of posttraumatic osteoarthritis. Currently, the most ‘valuable’ type of biologic reported for meniscus treatment was platelet-rich plasma. The main reported global research limitation was a lack of long-term clinical outcomes data. The most promising emerging medical technologies for improving meniscus science were 3-D printing, personalized medicine, and artificial implants.

Conclusions

This survey suggests that the future of meniscus science should be focused on meniscal preservation techniques through meniscus repair, addressing meniscal extrusion, and the use of orthobiologics. The lack of long-term clinical outcomes was the main reported research limitation globally for meniscus treatment. Future product development utilizing emerging medical technologies suggest the use of 3-D printing for meniscal transplants/scaffolds, personalized treatment, and bioengineering for artificial implants.

Level of Evidence

Level V.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40634-021-00345-y.

Rotator Cuff Retears

» Regardless of recent advances in rotator cuff repair techniques, the rate of unhealed or recurrent rotator cuff tears remains high, with most recurrent rotator cuff tears occurring within the first 6 months after surgery. » Factors that can negatively affect tendon healing include older age, greater tear size, tendon retraction, and fatty infiltration. However, several clinical features that are often underestimated, including osteoporosis, diabetes, smoking, and hyperlipidemia, have proven to have an important influence on rotator cuff healing. » Recent meta-analyses that evaluated studies with Level-I and Level-II evidence have shown an overall increase in retear rates after single-row repair compared with double-row repair. However, to our knowledge, there are no Level-I clinical studies comparing different double-row configurations and, to date, no double-row repair technique has proven to be superior to the others. » The influence of postoperative rotator cuff healing on clinical outcomes is controversial. Although clinical differences may not be apparent in the short term, healed tendons have had better functional outcomes and greater strength in the midterm. » In general, a period of immobilization for 2 to 4 weeks, depending on tear size, is recommended. Graded supervised rehabilitation has proven to facilitate tendon healing without associated stiffness compared with early unprotected range of motion.

Platelet-Rich Plasma in Patients With Partial-Thickness Rotator Cuff Tears or Tendinopathy Leads to Significantly Improved Short-Term Pain Relief and Function Compared With Corticosteroid Injection: A Double-Blind Randomized Controlled Trial

PURPOSE

To perform a randomized controlled trial comparing platelet-rich plasma (PRP) with standard corticosteroid (CS) injection in providing pain relief and improved function in patients with rotator cuff tendinopathy and partial-thickness rotator cuff tears (PTRCTs).

METHODS

This double-blind randomized controlled trial enrolled patients with ultrasound-proven or magnetic resonance imaging-proven PTRCTs who received either an ultrasound-guided PRP or CS injection. Patients completed patient-reported outcome assessments at baseline and at 6 weeks, 3 months, and 12 months after injection. The primary outcome was improvement in the visual analog scale (VAS) score for pain. Secondary outcomes included changes in American Shoulder and Elbow Surgeons (ASES) and Western Ontario Rotator Cuff Index (WORC) scores. Treatment failure was defined as subsequent injection, consent to undergo surgery, or operative intervention.

RESULTS

We followed up 99 patients (47 in the PRP group and 52 in the CS group) until 12 months after injection. There were no differences in baseline patient demographic characteristics including age, sex, or duration of symptoms. Despite randomization, patients in the PRP group had worse baseline VAS (46.0 vs 34.7, P = .01), ASES (53.9 vs 61.8, P = .02), and WORC (42.2 vs 49.5, P = .03) scores. At 3 months after injection, the PRP group had superior improvement in VAS (-13.6 vs 0.4, P = .03), ASES (13.0 vs 2.9, P = .02), and WORC (16.8 vs 5.8, P = .03) scores. There were no differences in patient-reported outcomes at 6 weeks or 12 months. There was no difference in the rate of failure (P = .31) or conversion to surgery (P = .83) between groups.

CONCLUSIONS

Patients with PTRCTs or tendinopathy experienced clinical improvement in pain and patient-reported outcome scores after both ultrasound-guided CS and PRP injections. Patients who received PRP obtained superior improvement in pain and function at short-term follow-up (3 months). There was no sustained benefit of PRP over CS at longer-term follow-up (12 months).

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

Platelet Rich Plasma in Orthopedic Surgical Medicine

There is a global interest in optimizing post-surgical tissue repair strategies, leading to better patient outcomes and fewer complications, most ideally with reduced overall cost. In this regard, in recent years, the interest in autologous biological treatments in orthopedic surgery and sports medicine has increased greatly, and the addition of platelet-rich plasma (PRP) to the surgical armamentarium is of particular note. Unfortunately, the number of PRP preparation devices has also grown immensely over the recent decades, raising meaningful concern for the considerable variation in the qualities of currently available PRP preparations. The lack of consensus on the standardization of PRP preparation and of agreement on condition specific PRP formulations is largely responsible for the sometimes contradictory outcomes in the literature. Furthermore, the full potential of PRP technology, the concept of individualized treatment protocols based on bioformulation options, and platelet dosing, angiogenesis, and antimicrobial and painkilling effects of PRP relevant to orthopedic surgery have rarely been addressed. In this review, we will discuss recent developments regarding PRP preparations and potential therapeutic effects. Additionally, we present a synopsis of several published data regarding PRP applications in orthopedic surgery for treating tendon injuries, inducing bone repair, strengthening spinal fusion outcomes, and supporting major joint replacements.

The use of biologics in professional and Olympic sport: a scoping review protocol

Aims

The use of biologics in the treatment of musculoskeletal injuries in Olympic and professional athletes appears to be increasing. There are no studies which currently map the extent, range, and nature of existing literature concerning the use and efficacy of such therapies in this arena. The objective of this scoping review is to map the available evidence regarding the use of biologics in the treatment of musculoskeletal injuries in Olympic and professional sport.

Methods

Best-practice methodological frameworks suggested by Arksey and O’Malley, Levac et al, and the Joanna Briggs Institute will be used. This scoping review will aim to firstly map the current extent, range, and nature of evidence for biologic strategies to treat injuries in professional and Olympic sport; secondly, to summarize and disseminate existing research findings; and thirdly, to identify gaps in existing literature. A three-step search strategy will identify peer reviewed and non-peer reviewed literature, including reviews, original research, and both published and unpublished (‘grey’) literature. An initial limited search will identify suitable search terms, followed by a search of five electronic databases (MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Web of Science, and Google Scholar) using keyword and index terms. Studies will be screened independently by two reviewers for final inclusion.

Dissemination

We will chart key concepts and evidence, and disseminate existing research findings to practitioners and clinicians, through both peer reviewed and non-peer reviewed literature, online platforms (including social media), conference, and in-person communications. We will identify gaps in current literature and priorities for further study.

Stem Cells for Treatment of Musculoskeletal Conditions - Orthopaedic/Sports Medicine Applications

A myriad of musculoskeletal conditions afflicts a vast number of the world's population from birth to death. Countless pathological diseases and traumatic injuries (acute and chronic) contribute to different human disabilities, causing a tremendous financial toll on the economy of healthcare. The medical field is continually searching for novel ways to combat orthopedically related conditions. The immediate goal is the restoration of anatomy then ultimately return of function in hopes of enhancing quality if not the quantity of life. Traditional methods involve surgical correction/reconstruction of skeletal deformities from fractures/soft tissue damage/ruptures or replacement/resection of degenerated joints. Modern research is currently concentrating on innovative procedures to replenish/restore the human body close to its original/natural state [1, 2].

Safety and efficacy of treating symptomatic, partial-thickness rotator cuff tears with fresh, uncultured, unmodified, autologous adipose-derived regenerative cells (UA-ADRCs) isolated at the point of care: a prospective, randomized, controlled first-in-human pilot study

Background

This study tested the hypothesis that treatment of symptomatic, partial-thickness rotator cuff tears (sPTRCT) with fresh, uncultured, unmodified, autologous adipose-derived regenerative cells (UA-ADRCs) isolated from lipoaspirate at the point of care is safe and more effective than corticosteroid injection.

Methods

Subjects aged between 30 and 75 years with sPTRCT who did not respond to physical therapy treatments for at least 6 weeks were randomly assigned to receive a single injection of an average 11.4 × 10⁶ UA-ADRCs (in 5 mL liquid; mean cell viability: 88%) (n = 11; modified intention-to-treat (mITT) population) or a single injection of 80 mg of methylprednisolone (40 mg/mL; 2 mL) plus 3 mL of 0.25% bupivacaine (n = 5; mITT population), respectively. Safety and efficacy were assessed using the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), RAND Short Form-36 Health Survey, and pain visual analogue scale (VAS) at baseline (BL) as well as 3 weeks (W3), W6, W9, W12, W24, W32, W40, and W52 post treatment. Fat-saturated T2-weighted magnetic resonance imaging of the shoulder was performed at BL as well as at W24 and W52 post treatment.

Results

No severe adverse events related to the injection of UA-ADRCs were observed in the 12 months post treatment. The risks connected with treatment of sPTRCT with UA-ADRCs were not greater than those connected with treatment of sPTRCT with corticosteroid injection. However, one subject in the corticosteroid group developed a full rotator cuff tear during the course of this pilot study. Despite the small number of subjects in this pilot study, those in the UA-ADRCs group showed statistically significantly higher mean ASES total scores at W24 and W52 post treatment than those in the corticosteroid group (p < 0.05).

Discussion

This pilot study suggests that the use of UA-ADRCs in subjects with sPTRCT is safe and leads to improved shoulder function without adverse effects. To verify the results of this initial safety and feasibility pilot study in a larger patient population, a randomized controlled trial on 246 patients suffering from sPTRCT is currently ongoing.

Trial registration

Clinicaltrials.gov ID NCT02918136. Registered September 28, 2016, https://clinicaltrials.gov/ct2/show/NCT02918136.

Level of evidence

Level I; prospective, randomized, controlled trial.

Arthroscopic partial repair with versus without biodegradable subacromial spacer for patients with massive rotator cuff tears: a case-control study

BACKGROUND

To investigate whether arthroscopic partial repair with the additional use of a biodegradable subacromial spacer would be proven better treatment for irreparable massive rotator cuff tears (MRCT) compared to single arthroscopic partial repair.

METHODS

A matched-pairs case-control study of 32 patients suffering from irreparable MRCT who underwent an arthroscopic partial repair with (Group B: 16 patients) or without (Group A: 16 patients) InSpace Balloon (ISB^®; Orthospace, Caesarea, Israel) implantation was conducted. For the clinical and functional assessment of the patients, the visual analog scale, Constant score, American Shoulder and Elbow Surgeons Shoulder Score (ASES), Range of Motion (RoM), and patients' satisfaction were obtained.

RESULTS

The two groups were matched in all baseline demographic and clinical characteristics (n.s.). All mean final quantitative postoperative clinical and functional scores of group A (partial repair and ISB) and group B (single partial repair), as well as active RoM, were significantly improved (t test) in comparison with the mean preoperative values (p < 0.05). No significant differences were observed between the two groups in relation to the two success rate criteria (ASES minimal clinically important difference or MCID > 17, Constant score MCID > 10.4), as well as pain relief and RoM 12 months after surgery.

CONCLUSION

Arthroscopic partial repair, either with or without ISB implantation, resulted in significantly improved clinical and functional short-term outcomes for the treatment of MRCT. Patients who were treated with combined partial repair and ISB implantation had a potential propensity toward better functional outcomes and higher patient satisfaction compared to the single-partial-repair-treated group. However, given that these differences were not significant, we feel that further studies are required to clarify the potential therapeutic value of ISB implantation in the treatment of irreparable MRCT.

LEVEL OF EVIDENCE

Level III.

CLINICAL TRIALS' REGISTRY

German Clinical Trials Register (WHO International Clinical Trials Registry Platform). ID number: DRKS00014725. Date of registration: 07/05/2018.

A 3-Dimensional Bioprinted Scaffold With Human Umbilical Cord Blood-Mesenchymal Stem Cells Improves Regeneration of Chronic Full-Thickness Rotator Cuff Tear in a Rabbit Model

BACKGROUND

Chronic full-thickness rotator cuff tears (FTRCTs) represent a major clinical concern because they show highly compromised healing capacity.

PURPOSE

To evaluate the efficacy of using a 3-dimensional (3D) bioprinted scaffold with human umbilical cord blood (hUCB)-mesenchymal stem cells (MSCs) for regeneration of chronic FTRCTs in a rabbit model.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 32 rabbits were randomly assigned to 4 treatment groups (n = 8 per group) at 6 weeks after a 5-mm FTRCT was created on the supraspinatus tendon. Group 1 (G1-SAL) was transplanted with normal saline. Group 2 (G2-MSC) was transplanted with hUCB-MSCs (0.2 mL, 1 × 10⁶) into FTRCTs. Group 3 (G3-3D) was transplanted with a 3D bioprinted construct without MSCs, and group 4 (G4-3D+MSC) was transplanted with a 3D bioprinted construct containing hUCB-MSCs (0.2 mL, 1 × 10⁶ cells) into FTRCTs. All 32 rabbits were euthanized at 4 weeks after treatment. Examination of gross morphologic changes and histologic results was performed on all rabbits after sacrifice. Motion analysis was also performed before and after treatment.

RESULTS

In G4-3D+MSC, newly regenerated collagen type 1 fibers, walking distance, fast walking time, and mean walking speed were greater than those in G2-MSC based on histochemical and motion analyses. In addition, when compared with G3-3D, G4-3D+MSC showed more prominent regenerated tendon fibers and better parameters of motion analysis. However, there was no significant difference in gross tear size among G2-MSC, G3-3D, and G4-3D+MSC, although these groups showed significant decreases in tear size as compared with the control group (G1-SAL).

CONCLUSION

Findings of this study show that a tissue engineering strategy based on a 3D bioprinted scaffold filled with hUCB-MSCs can improve the microenvironment for regenerative processes of FTRCT without any surgical repair.

CLINICAL RELEVANCE

In the case of rotator cuff tear, the cell loss of the external MSCs can be increased by exposure to synovial fluid. Therefore, a 3D bioprinted scaffold in combination with MSCs without surgical repair may be effective in increasing cell retention in FTRCT.

Anterior cruciate ligament repair versus reconstruction: A kinematic analysis

BACKGROUND

The purpose of this study was to compare the biomechanical properties of an anterior cruciate ligament (ACL) anatomic repair of a true femoral avulsion to an anatomic ACL reconstruction. It was hypothesized that the ACL repair and ACL reconstruction would have comparable biomechanical behavior when compared to the native knee.

METHODS

Ten paired fresh-frozen cadaveric knees (n = 20) were used to investigate knee kinematics when an anterior drawer force, varus, valgus, internal, and external rotational moment were applied at 0, 15, 30, 45, 60, and 90 degrees of flexion. Displacement and rotation were recorded in the following conditions: ACL-intact, ACL-deficient, and ACL-repaired vs reconstructed.

RESULTS

Sectioning of the ACL significantly increased anterior tibial translation (0°, 15°, 30° and 45°) compared to the intact state. The mean anterior displacement difference from intact was lower in the ACL-repaired knees compared to reconstructed knees at 30° and 90°. There were no significant differences between conditions in varus, valgus, internal, or external rotations.

CONCLUSION

ACL repair and ACL reconstruction procedures restored knee anterior tibial translation in matched paired specimens. There were no differences in valgus, varus, internal, or external rotation. Although, ACL-repaired knees (avulsion model) demonstrated less anterior tibial translation when compared to ACL-reconstructed knees, this difference was less than one millimeter. Based on the findings of this study, repair and reconstruction procedures both restored anterior tibial translation in matched-pair specimens. This suggests that the initial functionality of both techniques is similar and that further clinical studies are needed to compare the long-term stability.

Rogue stem cell clinics

Cell therapies hold significant promise for the treatment of injured or diseased musculoskeletal tissues. However, despite advances in research, there is growing concern about the increasing number of clinical centres around the world that are making unwarranted claims or are performing risky biological procedures. Such providers have been known to recommend, prescribe, or deliver so called ‘stem cell’ preparations without sufficient data to support their true content and efficacy. In this annotation, we outline the current environment of stem cell-based treatments and the strategies of marketing directly to consumers. We also outline the difficulties in the regulation of these clinics and make recommendations for best practice and the identification and reporting of illegitimate providers.

Cite this article: Bone Joint J 2020;102-B(2):148–154

A Practical Guide for the Current Use of Biologic Therapies in Sports Medicine

Over the past decade, there has been an increased interest in the use of biologic therapies in sports medicine. Although these technologies are in relatively early stages of development, there have been substantial increases in marketing, patient demand, and clinical utilization of biologics, including platelet-rich plasma, bone marrow aspirate concentrate, and other cell-derived therapies. Direct-to-consumer marketing of biologics has also proliferated but is largely unregulated, and clinicians must accurately convey the safety and efficacy profiles of these therapies to patients. Because most insurance companies consider biologic treatments to be experimental or investigational for orthopaedic applications given the lack of high-quality evidence to support their efficacy, patients receiving these treatments often make substantial out-of-pocket payments. With a range of treatment costs among centers offering biologics, there is a need for appropriate and sustainable pricing and reimbursement models. Clinicians utilizing biologics must also have a thorough understanding of the recently clarified Food and Drug Administration guidelines that regulate the clinical use of cell and tissue products. There is a lack of consensus on the optimal preparation, source, delivery method, and dosing of biologic therapies, which has been exacerbated by a lack of sufficient experimental detail in most published studies. Future research must better identify the biologic target of treatment, adhere to better standards of reporting, and better integrate researchers, industry, and regulatory bodies to optimize applications.

A Randomized Controlled Trial of the Treatment of Rotator Cuff Tears with Bone Marrow Concentrate and Platelet Products Compared to Exercise Therapy: A Midterm Analysis

Injectable regenerative therapies such as bone marrow concentrate (BMC) and platelet-rich plasma (PRP) may represent a safe alternative in the treatment of rotator cuff tears. This is a midterm review of a randomized, crossover trial comparing autologous BMC and platelet product injections versus exercise therapy in the treatment of partial and full-thickness supraspinatus tears. Patients enrolled into the study were between 18 and 65 years of age presenting to an outpatient orthopedic clinic with partial to full thickness, nonretracted supraspinatus tendon tears. Enrolled patients were randomized to either ultrasound-guided autologous BMC with PRP and platelet lysate (PL) percutaneous injection treatment or exercise therapy. Patients could cross over to BMC treatment after at least 3 months of exercise therapy. Patients completed the Disability of the Arm, Shoulder and Hand (DASH) scores as the primary outcome measure. Secondary outcomes included the numeric pain scale (NPS), a modified Single Assessment Numeric Evaluation (SANE), and a blinded MRI review. At this midterm review, results from 25 enrolled patients who have reached at least 12-month follow-up are presented. No serious adverse events were reported. Significant differences were seen in patient reported outcomes for the BMC treatment compared to exercise therapy at 3 and 6 months for pain, and for function and reported improvement (SANE) at 3 months (p < .05). Patients reported a mean 89% improvement at 24 months, with sustained functional gains and pain reduction. MRI review showed a size decrease of most tears post-BMC treatment. These findings suggest that ultrasound-guided BMC and platelet product injections are a safe and useful alternative to conservative exercise therapy of torn, nonretracted supraspinatus tendons. This trial is registered with NCT01788683.

Cryopreserved amniotic membrane and umbilical cord particulate matrix for partial rotator cuff tears: A case series

Amniotic membrane (AM) and umbilical cord (UC) are well known to have anti-inflammatory properties and have been shown to promote healing in various orthopedic indications. This study investigated whether intra-articular injection of AM/UC particulate matrix promotes healing of partial rotator cuff tears (RCTs).A case series was performed on 10 patients that received injection of 50 mg AM/UC for partial RCTs that were refractory to conservative treatment. Outcomes included Penn Shoulder Score (PSS) questionnaire, range of motion examination, and magnetic resonance imaging (MRI) analysis before and at 6 months. Final MRI analysis was performed by a musculoskeletal radiologist in a blinded fashion.Average PSS score (out of 100) increased from 46.8 ± 23.7 at baseline to 82.0 ± 19.1 at 6 months. The average PSS sub-scores of pain, satisfaction, and function increased 78.4%, 37.1%, and 82.3% from baseline, respectively. The subject's range of motion was 77.9% at baseline and increased to 99.9% at 6-months. Follow-up MRI scans did not demonstrate any significant change in RCT size. No adverse events were noted.This small case series provides preliminary data for use of cryopreserved AM/UC particulate matrix in patients with refractory partial RCTs.

International Expert Consensus on a Cell Therapy Communication Tool: DOSES

BACKGROUND

The lack of a standardized system for describing cell therapies acts as a barrier to advancement in clinical and basic research and practice. The aim of this study was to establish an international expert consensus on strategies to improve standardization and transparency when describing cell therapies. The secondary aim was to develop a consensus among experts on the contents of a standardized tool for describing cell therapies.

METHODS

The need for expert consensus on strategies to improve cell therapy communication was confirmed at the American Academy of Orthopaedic Surgeons/National Institutes of Health Optimizing Clinical Use of Biologics Symposium in 2018. A working group of 6 experts convened an international consensus process involving clinicians and basic scientists using validated Delphi methodology. This iterative process was used to define statements on communication of cell therapies and develop a standardized tool for describing cell therapies.

RESULTS

Thirty-four experts completed 3 rounds survey with use of the Delphi process. After 3 rounds, 27 statements relating to existing nomenclature, solutions to improve communication, ideal characteristics of a framework, mandatory elements of a new framework, and future work to facilitate application reached consensus with >80% agreement and <5% disagreement. Consensus was reached on the contents of a tool for improving standardization and transparency when describing cell therapies. This tool, dubbed "DOSES," is based on the reporting of 5 core items: donor (i.e., autologous, allogeneic, xenogeneic), origin of tissue, separation from other cell types/preparation method, exhibited cell characteristics associated with behavior, and the site of delivery.

CONCLUSIONS

This study has established expert consensus on the communication of cell therapies. The DOSES tool has been developed to improve standardization and transparency in describing cell therapies.

CLINICAL RELEVANCE

The DOSES tool for describing cell therapies can be utilized by researchers, clinicians, regulators, and industry professionals to improve standardization and transparency when describing cell therapies. The use of this tool may allow clinicians and patients to better understand the characteristics of current and future cell preparations.

Reporting of Mesenchymal Stem Cell Preparation Protocols and Composition: A Systematic Review of the Clinical Orthopaedic Literature

BACKGROUND

Mesenchymal stem cells (MSCs) are increasingly being used in the treatment of a wide variety of sports-related conditions. Despite this enthusiasm, the biological properties of MSCs and their effects on musculoskeletal tissue healing remain poorly understood. MSC-based strategies encompass cell populations with heterogeneous phenotypes isolated from multiple tissues and using different methods. Therefore, comprehensive reporting of the source, preparation methods, and characteristics of MSC strategies is essential to enable interpretation of results.

PURPOSE

To perform a systematic review of levels of reporting of key variables in MSC preparation and composition for clinical studies evaluating MSC-based therapies in the treatment of musculoskeletal conditions.

STUDY DESIGN

Systematic review.

METHODS

A systematic review of the clinical orthopaedic and sports medicine literature from 2002 to 2017 was performed. The following inclusion criteria were used: human clinical trials, published in the English language, involving the administration of MSC-based therapies for orthopaedic or sports medicine applications. In vitro or ex vivo studies, editorials, letters to the editor, and studies relating to cosmetic, neurological, or dental applications were excluded.

RESULTS

Of the 1259 studies identified on the initial search, 36 studies were found to satisfy the inclusion criteria for analysis on comprehensive review. Fifty-seven percent of studies evaluated bone marrow-derived MSCs, 41% evaluated adipose-derived MSCs, and 2% evaluated synovium-derived MSCs. Considerable deficiencies in the reporting of key variables, including the details of stem cell processing, culture conditions, and the characteristics of cell populations delivered, were noted. Overall, studies reported only 52% (range, 30%-80%) of variables that may critically influence outcome. No study provided adequate information relating to all of these variables.

CONCLUSION

All existing clinical studies evaluating MSCs for orthopaedic or sports medicine applications are limited by inadequate reporting of both preparation protocols and composition. Deficient reporting of the variables that may critically influence outcome precludes interpretation, prevents others from reproducing experimental conditions, and makes comparisons across studies difficult. We encourage the adoption of emerging minimum reporting standards for clinical studies evaluating the use of MSCs in orthopaedics.

The Influence of Naproxen on Biological Factors in Leukocyte-Rich Platelet-Rich Plasma: A Prospective Comparative Study

PURPOSE

To quantify and compare normative catabolic and anabolic factor concentrations in leukocyte-rich platelet-rich plasma (LR-PRP) at various time points, including baseline, 1 week after initiating naproxen use, and after a 1-week washout period.

METHODS

Asymptomatic healthy donors aged between 18 and 70 years were recruited (average age, 36.6 years; range, 25-64 years). Subjects were excluded from the study if they were actively taking any prescribed medications or nonsteroidal anti-inflammatory drugs (NSAIDs) or if they had any of the following at present or previously: blood or immunosuppression disorders, cancer, osteonecrosis, rheumatoid arthritis, avascular necrosis, NSAID intolerance, gastrointestinal or peptic ulcer disease, or kidney dysfunction. The anabolic factors vascular endothelial growth factor, fibroblast growth factor 2, platelet-derived growth factor AB (PDGF-AB), and platelet-derived growth factor AA (PDGF-AA) and the catabolic factors interleukin (IL) 1β, IL-6, IL-8, and tumor necrosis factor α in LR-PRP were measured. Peripheral blood was drawn at 3 time points: baseline, after 1 week of naproxen use, and after a 1-week washout period.

RESULTS

The angiogenic factors PDGF-AA (44% decrease in median) and PDGF-AB (47% decrease) significantly declined from baseline (P < .05) after 1 week of naproxen use. There was a significant recovery (P < .05) of PDGF-AA (94% increase) and PDGF-AB (153% increase) levels after the 1-week washout period, with a return to baseline levels. The catabolic factor IL-6 also had a significant decline from baseline (77% decrease in median, P < .05) after 1 week of naproxen use. After a 1-week washout period, the IL-6 level was similar to the baseline level (130% increase, P < .05).

CONCLUSIONS

Naproxen use diminished several biological factors in LR-PRP; however, a 1-week washout period was sufficient for the recovery of PDGF-AA, PDGF-AB, and IL-6 to return to baseline levels. Tumor necrosis factor α, IL-1β, IL-8, vascular endothelial growth factor, and fibroblast growth factor 2 did not show differences between the 3 time points of data collection. Discontinuing NSAIDs for a minimum of 1 week before LR-PRP treatment may improve certain biological factor levels.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

The Economics and Regulation of PRP in the Evolving Field of Orthopedic Biologics

PURPOSE OF REVIEW

This review provides an update on the current status of platelet-rich plasma (PRP). Topics covered include the current regulatory environment, economic outlook, and current clinical evidence.

RECENT FINDINGS

The global PRP market is expected to grow to between 380 million and 4.5 billion (USD) over the next 5-10 years. The cost of a single treatment, which is not covered by most insurance, is roughly $500-$2500, with patients often returning for additional treatments. While PRP is not 'FDA-approved', it can be legally offered in the clinic 'off-label' in the USA for a myriad of musculoskeletal indications. Recently published meta-analyses have demonstrated statistically significant improvements that, in some cases, suggest that PRP may have clinically meaningful effects. However, given the fact that clearance is not synonymous with approval, PRP is a costly treatment not covered by insurance, and clinical trials have not demonstrated definitive efficacy, we recommend informing patients when providing PRP 'off-label'.

Biological Treatment for Osteoarthritis of the Knee: Moving from Bench to Bedside-Current Practical Concepts

Biological-based therapies for cartilage pathology have gained considerable recognition in the last few decades due to their potential benefits including their minimal invasiveness, capacity for unprecedented healing, and potential for rapid recovery. Consequently, these therapies are likely to have the most noteworthy impact on patients with degenerative joint changes who want to remain active. Currently, the most researched treatments include platelet-rich plasma (PRP), bone marrow aspirate concentrate (BMAC), and cell-based therapies. Although further basic science research and well-designed randomized clinical trials are needed to elucidate the long-term role of these therapies in the treatment of osteoarthritis, there is compelling evidence for their use for certain indications. This article aims to review the existing literature for biological-based treatment options for osteoarthritis, critically assessing the current evidence-based recommendations and identify potential avenues for development.

Use of Platelet-Rich Plasma Immediately After an Injury Did Not Improve Ligament Healing, and Increasing Platelet Concentrations Was Detrimental in an In Vivo Animal Model

BACKGROUND

Limited information in basic science and clinical trials exists to determine if ligament healing may be accelerated with the use of biological adjuvants, such as platelet-rich plasma (PRP). However, there has been widespread acceptance of PRP for use in clinical practice, despite an inadequate understanding of its biological mechanism of action.

PURPOSE

To determine whether a single dose of PRP could accelerate ligament healing and correspondingly improve histological characteristics and biomechanical properties when injected immediately postoperatively into the injured medial collateral ligament (MCL) of New Zealand White rabbits.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eighty skeletally mature New Zealand White rabbits (160 knees) were used. The MCL was torn midbody to simulate a grade 3 tear. After an acute injury of the MCL, the administration of autologous PRP at 3 different platelet concentrations (0 million/uL, platelet-poor plasma [PPP]; 0.6 million/uL, 2 times the baseline [2× PRP]; and 1.2 million/uL, 4 times the baseline [4× PRP]) was performed and compared with a saline injection control in the contralateral knee. Histological analysis and a biomechanical endpoint characterization were utilized to assess ligamentous healing and compare it to a sham surgery group.

RESULTS

The PPP ( P = .001) and 4× PRP ( P = .002) groups had a significantly lower collagen subscore than the sham surgery group. No other differences were observed among the treatment groups, including the vascularity subscore and overall ligament tissue maturity index score. Compared with saline-injected contralateral knees, the maximum load for PPP and 2× PRP was not significantly different ( P = .788 and .325, respectively). The maximum load and stiffness for knees treated with 4× PRP were significantly less than for the saline-treated contralateral knees ( P = .006 and .001, respectively).

CONCLUSION

One single dose of PPP or 2× PRP at the time of injury did not improve ligament healing. In addition, 4× PRP negatively affected ligament strength and histological characteristics at 6 weeks after the injury.

CLINICAL RELEVANCE

The current practice of treating knee ligament injuries with PRP may not improve healing at low doses of PRP. The decreased mechanical properties and histological appearance of the torn MCL suggest that high doses of PRP decrease the quality of repair tissue. Further in vivo studies are necessary to determine the dosing and timing of PRP administration after a ligament injury before the widespread use of PRP to treat ligament injuries is recommended.

Effects of bone marrow aspirate concentrate and platelet-rich plasma on patients with partial tear of the rotator cuff tendon

Background

We compared the clinical course of rotator cuff tears between rotator cuff exercise and bone marrow aspirate concentration (BMAC)-platelet rich plasma (PRP) injection to identify the therapeutic effects of BMAC-PRP on partial tear of the rotator cuff tendon.

Methods

Twenty-four patients with partial tear of the rotator cuff tendon participated in this study. Twelve patients underwent extraction of BMACs and PRP and received the injection of BMAC-PRP at the tear site under ultrasound guidance. Twelve patients in the control group were asked to perform the rotator cuff exercise for 3 months. Visual analog scale (VAS) and manual muscle test (MMT) scores of the supraspinatus muscle were measured, and the American Shoulder and Elbow Surgeons (ASES) score was recorded before, 3 weeks, and 3 months after injection. Tear size was measured by the greatest longitudinal tear length.

Results

The change in the VAS differed between groups at 3 months (P = 0.039) but not at 3 weeks (P = 0.147). The ASES scores in the BMAC-PRP group changed from 39.4 ± 13.0 to 54.5 ± 11.5 at 3 weeks and 74.1 ± 8.5 at 3 months while those in the control group changed from 45.9 ± 12.4 to 56.3 ± 12.3 at 3 weeks (P = 0.712) and 62.2 ± 12.2 at 3 months (P = 0.011). The tear size decreased at 3 weeks or 3 months after the BMAC-PRP injection but was not significantly different from that in the control group.

Conclusions

BMAC-PRP improved pain and shoulder function in patients with partial tear of the rotator cuff tendon.

Trial registration

The patients were registered in the institutional board registry of Samsung Medical Center (registry number 2014-07-173).

Electronic supplementary material

The online version of this article (10.1186/s13018-017-0693-x) contains supplementary material, which is available to authorized users.

A Call for Standardization in Platelet-Rich Plasma Preparation Protocols and Composition Reporting: A Systematic Review of the Clinical Orthopaedic Literature

BACKGROUND

Platelet-rich plasma (PRP) is a blood-derived preparation whose use has grown exponentially in orthopaedic practice. However, there remains an unclear understanding of the biological properties and effects of PRP on musculoskeletal healing. Heterogeneous processing methods, unstandardized nomenclature, and ambiguous classifications make comparison among studies challenging. A comprehensive assessment of orthopaedic clinical PRP trials is key to unraveling the biological complexity of PRP, while improving standardized communication. Toward this goal, we performed a systematic review of the PRP preparation protocols and PRP composition utilized in clinical trials for the treatment of musculoskeletal diseases.

METHODS

A systematic review of the literature was performed from 2006 to 2016. Inclusion criteria were human clinical trials, English-language literature, and manuscripts that reported on the use of PRP in musculoskeletal/orthopaedic conditions. Basic-science articles, editorials, surveys, special topics, letters to the editor, personal correspondence, and nonorthopaedic applications (including cosmetic use or dental application studies) were excluded.

RESULTS

A total of 105 studies (in 104 articles) met the inclusion criteria for analysis. Of these studies, only 11 (10%) provided comprehensive reporting that included a clear description of the preparation protocol that could be used by subsequent investigators to repeat the method. Only 17 studies (16%) provided quantitative metrics on the composition of the final PRP product.

CONCLUSIONS

Reporting of PRP preparation protocols in clinical studies is highly inconsistent, and the majority of studies did not provide sufficient information to allow the protocol to be reproduced. Furthermore, the current reporting of PRP preparation and composition does not enable comparison of the PRP products being delivered to patients. A detailed, precise, and stepwise description of the PRP preparation protocol is required to allow comparison among studies and provide reproducibility.

Minimum Information for Studies Evaluating Biologics in Orthopaedics (MIBO): Platelet-Rich Plasma and Mesenchymal Stem Cells

BACKGROUND

A comprehensive approach to the evaluation of biologic therapies for musculoskeletal conditions is required to guide appropriate future use. Clinical studies evaluating platelet-rich plasma (PRP) and mesenchymal stem cells (MSCs) are limited by inadequate reporting of scientific details critical to outcome. We developed minimum reporting requirements for clinical studies evaluating PRP and MSCs using Delphi consensus methods.

METHODS

The need for consensus on the minimum reporting requirements for studies evaluating biologics was identified at the American Academy of Orthopaedic Surgeons/Orthopaedic Research Society (AAOS/ORS) Biologic Treatments for Orthopaedic Injuries Symposium in 2015 and the American Orthopaedic Society for Sports Medicine (AOSSM) Biologic Treatments for Sports Injuries II Think Tank in 2015. A working group facilitated the development of 2 expert consensus statements for PRP and MSCs using Delphi techniques. Exhaustive lists of items that could be reported on by clinical studies evaluating PRP or MSCs were generated by searching the published literature and protocols. PRP and MSC expert groups, each made up of 24 invited speakers at the AAOS and AOSSM symposia, were surveyed on 3 occasions to establish consensus on the inclusion of each item within minimum reporting guidelines. In addition to rating their agreement, the experts were encouraged to propose further items or modifications. Predefined criteria were used to refine item lists after each survey. Final lists were compiled into checklist statements by the working group.

RESULTS

For PRP, the working group identified 93 experimental information items from the literature. Twenty-three experts (96%) completed 3 rounds of surveys. After 3 rounds, 58 items generated consensus with >75% agreement and <5% disagreement. These items were compiled into a 23-statement checklist. For MSCs, 103 items were identified from the published literature. Twenty-three experts (96%) completed 3 rounds of surveys. After 3 rounds, the 61 items for which consensus was reached were compiled into a 25-statement checklist.

CONCLUSIONS

This study has established expert consensus on the minimum reporting requirements for clinical studies evaluating PRP and MSCs.

CLINICAL RELEVANCE

These checklists provide specifications for the minimum information that should be reported by clinical studies evaluating PRP or MSCs.

Could Disruption of the Shoulder Superior Capsule Be the "Essential Lesion" of Rotator Cuff Disease? Possibly, but Questions Remain…

Rotator cuff disease remains a complex clinical problem with significant variation in pathology, clinical presentation, and management options. Functionally, humeral head depression is critical in restoring or maintaining arm elevation, and the shoulder superior capsule serves in this important function. Could disruption of the shoulder superior capsule be the "essential lesion" of rotator cuff disease? Possibly, but many questions remain unanswered, and substantial scientific evidence is required before we can assert with certainty that disruption of the superior capsule with resultant superior instability of the humeral head is the essential lesion of rotator cuff disease.