Chronic Tendinopathy Research Articles

Global research trends on platelet-rich plasma for tendon and ligament injuries from the past two decades: A bibliometric and visualized study.

In sports medicine, tendon and ligament injuries are the most prevalent conditions, and with the booming of sports competition, the incidence of sports injuries is gradually increasing, investigating more potent therapeutic options is therefore becoming increasingly crucial. Platelet-rich plasma therapy has gained popularity as an effective and secure treatment in recent years. Currently, a faceted systematic and clear visual analysis is lacking in this research area. The literature related to using platelet-rich plasma to treat ligament and tendon injuries from 2003 to 2022 in the core dataset of the Web of Science database was collected and analyzed visually using Citespace 6.1 software. Research hotspots and development trends were analyzed in terms of high-impact countries or regions, authors, research institutions, keywords, and cited literature. The literature comprised a total of 1,827 articles. The annual publication volume of relevant literature has demonstrated a significant development tendency as the field of platelet-rich plasma research for tendon and ligament injuries has heated up in recent years. With 678 papers, the United States came in top place, followed by China with 187 papers. Hosp Special Surg ranked first with 56 papers. The hot research topics analyzed by keywords were tennis elbow, anterior cruciate ligament, rotator cuff repair, achilles tendon, mesenchymal stem cells, guided tissue regeneration, network meta analysis, chronic patellar tendinopathy, and follow up. Analysis of the research literature over the past 20 years shows that the United States and China will continue to dominate in terms of volume of publications based on annual volume and trends, with some collaboration among high-impact authors and further collaboration still needed in different countries and institutions. Platelet-rich plasma is widely used in the treatment of tendon ligament injuries. Its clinical efficacy is influenced by a number of factors, the main ones being the inconsistency in the preparation and composition of platelet-rich plasma and its related preparations, and the differences in efficacy due to different activation methods of platelet-rich plasma, as well as factors such as injection time, injection site, administration method, number of administrations, acidity and evaluation methods, In addition, the applicability to different injury diseases remains controversial. In recent years, the molecular biology of platelet-rich plasma for tendon ligament therapy has received increasing attention.

Optimal Injection Volume in Treatment of Tendinopathy

Background: Tendinopathy, a pathology of tendons characterized by inflammation and or degeneration, is a prevalent cause of disease and disability in active and working patients. Within the past decade, orthobiologic injections such as Platelet Rich Plasma (PRP) have become increasingly popular within the musculoskeletal physician’s practice for treatment of chronic tendinopathies. However, there is a lack of standardization of PRP preparation and injection protocols, leading to gaps in our knowledge regarding the optimal administration dosages to maximize treatment efficacy. Purpose: This review aims to compile and evaluate the existing data for PRP injection volumes for various tendinopathies in hopes of contributing to standardization of PRP protocols, with a further goal of minimiz-ing waste of a costly therapeutic. Study Design: Systematic Review Methods: In June 2020, comprehensive electronic database searches were conducted by a medical librarian in Medline via PubMed, EMBASE (embase.com), CINAHL (EbscoHost), CENTRAL and Scopus according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data was extracted from studies meeting inclusion criteria on injection volumes and outcomes and grouped based on anatomic injection location. Results: Twenty-eight studies were identified for inclusion in which ultrasound-guided intra-tendinous PRP injections were administered to patients to treat various tendinopathies. For all tendon locations, the mini-mum volume of injectate reported achieved positive clinical outcomes in patients compared to baseline. Conclusions: Despite its many benefits—tendon healing, pain relief, increased function—PRP can pose a significant financial burden to patients, with patients often having to pay for the full cost out-of-pocket due to lack of insurance coverage. This study provides evidence that PRP can be effective at smaller volumes, minimizing waste and the out-of-pocket cost to the patient. In addition, this study further stresses the impor-tance of protocol standardization. Clinical Relevance: Though more data is needed, it is apparent that the minimum amount of injectate used clinically for various anatomic locations is enough for overall positive outcomes, and therefore can be the recommended dose given. As such, the authors have incorporated the minimum injection volume into their practice using the following volumes: Rotator Cuff-1 mL, Lateral or Medial Epicondyle-1.5 mL, Gluteal or Hamstring-3 mL, Patella-2 mL, Achilles-3 mL. Unfortunately, without more data available in the literature, the authors cannot make stronger recommendations at this time. What is known about the subject: Among intralesional injections for the treatment of tendinopathy, PRP has shown positive results in multiple trials and has made its way into many musculoskeletal physicians’ practice. However, there is a significant lack of standardization in PRP protocols. What this study adds to existing knowledge: While other reviews have highlighted the discrepancies amongst PRP protocols, our review is the first to examine injection volume and its effect on outcomes. We were able to suggest a minimum injectate amount for positive outcomes, either pain relief or improvement in the tendon appearance on imaging.

Optimizing repair of tendon ruptures and chronic tendinopathies: Integrating the use of biomarkers with biological interventions to improve patient outcomes and clinical trial design.

Tendons are dense connective tissues of the musculoskeletal system that link bones with muscles to foster mobility. They have complex structures and exist in varying biomechanical, metabolic and biological environments. In addition, tendon composition and mechanical properties can change over the lifespan as an individual ages. Many tendons function in high stress conditions with a low vascular and neuronal supply, conditions often leading to development of chronic tendinopathies, and in some cases, overt rupture of the tissues. Given their essential nature for human mobility and navigation through the environment, the effective repair and regeneration of different tendons after injury or damage is critical for quality of life, and for elite athletes, the return to sport participation at a high level. However, for mainly unknown reasons, the outcomes following injury are not always successful and lead to functional compromise and risk for re-injury. Thus, there is a need to identify those patients who are at risk for developing tendon problems, as well those at risk for poor outcomes after injury and to design interventions to improve outcomes after injury or rupture to specific tendons. This review will discuss recent advances in the identification of biomarkers prognostic for successful and less successful outcomes after tendon injury, and the mechanistic implications of such biomarkers, as well as the potential for specific biologic interventions to enhance outcomes to improve both quality of life and a return to participation in sports. In addition, the implication of these biomarkers for clinical trial design is discussed, as is the issue of whether such biomarkers for successful healing of one tendon can be extended to all tendons or are valid only for tendons in specific biomechanical and biological environments. As maintaining an active lifestyle is critical for health, the successful implementation of these advances will benefit the large number of individuals at risk.

High intensity focused ultrasound atomization and erosion in healthy and tendinopathic tendons

Objective. High-intensity focused ultrasound (HIFU) can induce thermal and mechanical mechanisms in a well-defined focal volume of tissues. Histotripsy is a form of mechanical HIFU that can initiate and interact with bubble(s) to cause shock scattering and perhaps atomization within the bubble(s) to fractionate most soft tissues. Ultrasonic atomization, or the ejection of fine droplets from an acoustically-excited liquid exposed to air, has been shown to erode planar soft tissue surfaces, which has led to theories that atomization is a mechanism in histotripsy. However, healthy tendons show resistance to conventional histotripsy; pre-treatment of tendons with heat increases susceptibility to histotripsy fractionation. This study investigates ultrasonic atomization and erosion from planar healthy and tendinopathic tendon surfaces as we evaluate HIFU parameters for histotripsy in tendons. Approach. Forty-six ex vivo bovine tendon-air interfaces were pre-conditioned to surface wetting, heat baths of 20 °C (unaltered), 37 °C (body temperature), and 58 °C (collagen degradation), collagenase soaks for 1, 3, 5, and 24 h (mimicking tendinopathic tendons), and phosphate buffered saline soaks for 24 h. Ejected fragments, histology, and gross analysis determined erosion success. Tissue displacement from the HIFU radiation force was monitored with high-speed photography, and tissue relaxation was pixel-tracked and fit to a Kelvin–Voigt model to evaluate changes in viscoelastic properties. Main results. Results showed that atomization produced holes in 24 h collagenase tendons and surface pitting in 58 °C, 3 h, and 5 h collagenase tendons. Increased mound heights and viscoelastic constants in pre-heated (to 58 °C) and collagenase-soaking (3+ hours) tendinopathic models caused a decrease in elasticity and/or increase in viscosity, increasing susceptibility to erosion by HIFU atomization. Significance. Therefore, tendons with chronic tendinopathies may be more susceptible than healthy tendons to histotripsy fractionation.

Blood Flow Restriction Training for Tendinopathy Rehabilitation: A Potential Alternative to Traditional Heavy-Load Resistance Training

Tendinopathy is a chronic tendon disease which can cause significant pain and functional limitations for individuals, and which collectively places a tremendous burden on society. Resistance training has long been considered the treatment of choice in the rehabilitation of chronic tendinopathies, with both eccentric and heavy slow resistance training demonstrating positive clinical effects. The application of progressive tendon loads during rehabilitation is essential to not compromise tendon healing, with the precise dosage parameters of resistance training and external loading a critical consideration. Blood-flow restriction training (BFRT) has become an increasingly popular method of resistance training in recent years and has been shown to be an effective method for enhancing muscle strength and hypertrophy in healthy populations and in musculoskeletal rehabilitation. Traditional resistance training for tendinopathy requires the application of heavy training loads, whereas BFRT utilises significantly lower loads and training intensities, which may be more appropriate for certain clinical populations. Despite evidence confirming the positive muscular adaptations derived from BFRT and the clinical benefits found for other musculoskeletal conditions, BFRT has received a dearth of attention in tendon rehabilitation. Therefore, the purpose of this narrative review was threefold: firstly, to give an overview and analysis of the mechanisms and outcomes of BFRT in both healthy populations and in musculoskeletal rehabilitation. Secondly, to give an overview of the evidence to date on the effects of BFRT on healthy tendon properties and clinical outcomes when applied to tendon pathology. Finally, a discussion on the clinical utility of BFRT and its potential applications within tendinopathy rehabilitation, including as a compliment to traditional heavy-load training, is presented.

Comparison of ultrasound-guided subacromial corticosteroid and ozone (O2-O3) injections in the treatment of chronic rotator cuff tendinopathy: a randomized clinical trial.

: The authors aimed to compare the effects of a one-time ultrasound (US)-guided subacromial corticosteroid injection and three-time ozone (O2-O3) injection in patients with chronic supraspinatus tendinopathy. : Participants were randomly assigned to the corticosteroid group (n = 22) or ozone group (n = 22). Injections in both groups were administered into subacromial bursa with an US-guided in-plane posterolateral approach. Primary outcome measure was the change in the Western Ontario Rotator Cuff Index (WORC) score between baseline and 12-weeks post-injection. Secondary outcome measures included visual analog scale and Shoulder Pain and Disability Index scores. Assessments were recorded at baseline, and 4-weeks and 12-weeks post-injection. : Forty participants completed this study. Based on repeated measurement analysis of variance, a significant effect of time was found for all outcome measures in both groups. Both the groups showed clinically significant improvements in shoulder pain, quality of life, and function. Baseline, 4-week post-injection, and 12-week post-injection WORC scores (mean ± standard deviation) were 57.91 ± 18.97, 39.10 ± 20.50 and 37.22 ± 27.31 in the corticosteroid group, respectively and 69.03 ± 15.89, 39.11 ± 24.36, and 32.26 ± 24.58 in the ozone group, respectively. However, no significant group × time interaction was identified regarding all outcome measures. : Three-time ozone injection was not superior to a one-time corticosteroid injection in patients with chronic supraspinatus tendinopathy. It might be as effective as corticosteroid injection at 4-weeks and 12-weeks post-injection in terms of relieving pain and improving quality of life and function.

Dextrose prolotherapy for chronic tendinopathy: A scoping review

Tendinopathy is a frequent source of musculoskeletal pain and disability. Between treatment options, prolotherapy, an injection treatment that aims to promote tissue healing, could play a role in symptomatic and functional improvement. The purpose of the study is to analyze current evidence about the effect of dextrose injections on clinical outcomes in patients with chronic tendinopathy. A literature search on MEDLINE (PubMed) and PEDro databases was conducted. All randomized controlled trials (RCTs) published in the last 10 years, with available abstracts, in English language, analyzing the effect of prolotherapy in human subjects with a diagnosis of chronic tendinopathy were considered. Methodological quality was assessed by PEDRO scale quality assessment tool. Sixteen papers were included. Most of the RCTs were of medium to high quality. Based on the analyzed data, prolotherapy could represent an easy to access, cheap, safe and effective conservative treatment in rotator cuff tendinopathy and in epiconodylosis and could improve pain control in the medium to long-term, with encouraging data on function restoring in the long term. However, solutions preparation, procedural aspects and comparators were highly heterogeneous. Current evidence suggests that prolotherapy can results in improving symptoms in patients with tendinopathy, with no observed adverse reactions. However, few RCTs have been conducted; the results are not enough consistent and a wide heterogeneity in protocols makes comparing data not always possible. Therefore, further studies requiring, first, a proposal of a repeatable standardized procedure are needed to confirm the positive preliminary results.

Comparison of Clinical and Ultrasound Imaging Outcomes Between Corticosteroid and Hypertonic Dextrose Injections for Chronic Supraspinatus Tendinopathy

Both corticosteroids and hypertonic dextrose injections are commonly used for chronic supraspinatus tendinopathy. To compare the supraspinatus echogenicity and clinical effects of echo-guided hypertonic dextrose versus corticosteroid injection for treating chronic supraspinatus tendinopathy. Cohort study; Level of evidence, 3. The authors performed a secondary data analysis of a previous clinical trial including patients who received normal saline versus hypertonic dextrose injection; patients who received corticosteroid injection were recruited between August 2017 and July 2021. Baseline patient data were matched among these 3 groups at a 1:1:1 ratio. At baseline and 2, 6, and 12 weeks after the intervention, the authors compared morphological changes (supraspinatus thickness and echogenicity) and clinical parameters (visual analog scale [VAS] for pain, Shoulder Pain and Disability Index [SPADI], and range of motion [ROM]). Analysis of variance was used to compare mean changes from baseline among the groups. A total of 75 patients (25 in each group) were included. At 2-week follow-up, both the dextrose and the steroid groups exhibited improvement in VAS scores (mean difference [MD] from baseline: -2.0 in dextrose group; -3.3 in steroid group (P < .001)), SPADI scores (MD from baseline: -10.6 in dextrose group; -24.6 in steroid group (P < .001)), and flexion ROM (MD from baseline: 13.6° in dextrose group; 21.1° in steroid group) (P =.001). At 6 weeks after injection, the hypertonic dextrose group exhibited more favorable echogenic improvement in supraspinatus tendon morphology compared with the other 2 groups (P < .001). However, the steroid group showed significantly more improvement in clinical parameters compared with the other 2 groups at both week 6 (MD from baseline: VAS, -3.2; SPADI, -26.6; flexion ROM, 21.5°) and week 12 (MD from baseline: VAS, -2.5; SPADI, -20.4; flexion ROM, 15.2°) (P < .001 for all). Hypertonic dextrose injection improved supraspinatus echogenicity after 6 weeks but provided short-term symptomatic relief in the patients with chronic supraspinatus tendinopathy when compared with corticosteroid or saline injections. Steroid injection exerted a more favorable clinical effect at weeks 6 and 12 but demonstrated a negative effect on the supraspinatus.

Whole body vibration for chronic patellar tendinopathy: A randomized equivalence trial.

Purpose: Whole body vibration (WBV) triggers anabolic responses in various tissues, including tendons, without requiring high force production. In this waitlist-controlled equivalence trial, we tested its clinical effectiveness as an alternative treatment for patellar tendinopathy against conventional heavy slow resistance training (HSR). Methods: Thirty-nine patients were randomized to either 3months of WBV training (n = 13), HSR training (n = 11), or a waitlist control (WLC) group (n = 15). In a partly cross-over design, 14 patients of the WLC group were redistributed to one of the two intervention groups (5 in WBV, 9 in HSR). Pre- and post-intervention testing included pain assessments (VAS), functional limitations (VISA-P), knee extension strength and tendon morphological, mechanical and material properties. Follow-up measurements (VAS, VISA-P) were performed in the WBV and HSR groups 6months after the intervention. Results: Comparisons with the WLC group revealed significant improvements in VISA-P and VAS scores after HSR (41%, p = 003; 54%, p = 0.005) and WBV (22%, p = 0.022; 56%, p = 0.031) training. These improvements continued until follow-up (HSR: 43%, 56%; WBV: 24%, 37%). Pre-post improvements in VAS scores were equivalent between WBV and HSR groups but inconclusive for the VISA-P score and all pre-test to follow up comparisons. The mid-tendon cross-sectional area was significantly reduced after WBV (-5.7%, p = 0.004) and HSR (-3.0%, p = 0.004) training compared to WLC although the equivalence test between interventions was inconclusive. Conclusion: Whole body vibration improved symptoms typically associated with patellar tendinopathy. This type of intervention is as effective as HSR against maximum pain, although equivalence could not be confirmed for other variables. The beneficial responses to WBV and HSR treatments persisted for 6 months after the end of the intervention. Clinical Trial Registration: https://www.drks.de/drks_web/setLocale_EN.do, identifier DRKS00011338.

Pathological Tendon Histology in Early and Chronic Human Patellar Tendinopathy.

The present pilot study investigated the extent of histological tissue changes in both chronic tendinopathy and in individuals that display early clinical signs of tendinopathy. The study included 8 individuals of whom 3 were healthy without any tendon symptoms, 2 had early symptoms (1-2 months), and 3 had chronic symptoms (>3 months) from their patellar tendons. Percutaneous needle biopsy samples were obtained from the affected tendon tissue region. Biopsy samples were stained with Haematoxylin & Eosin, and multiplex immunofluorescence staining was performed for markers of inflammation and resolution. Both early and chronic stage patellar tendon biopsy samples from this small patient cohort exhibited expansion of the interfascicular matrix (IFM) and endotenon regions together with increased cellularity and vascularity. These histological observations were moderate in early tendinopathy, whereas they were more pronounced and associated with marked disruption of tissue architecture in chronic tendinopathy. Early stage tendinopathic patellar tendons expressed markers associated with an activated phenotype of fibroblasts (CD90, CD34), macrophages (S100A8), and endothelial cells (ICAM1, VCAM1). These tissues also expressed enzymes implicated in inflammation (PTGS2, 15PGDH) and resolution (ALOX12) and the proresolving receptor ERV1. Immunopositive staining for these markers was predominantly located in the IFM regions. These preliminary findings suggest that mild to moderate structural histological changes including expansion of IFM and endotenon regions are pathological features of early tendinopathy, and support inflammatory and resolving processes are active in early-stage disease. Further investigation of the cellular and molecular basis of early-stage tendinopathy is required to inform therapeutic strategies that prevent the development of irreversible chronic tendon disease.

The effects of percutaneous ultrasound tenotomy on chronic tendinopathy in a rabbit Achilles’ tendon model

Objective: Chronic tendinopathy is debilitating and significantly limits physical function and quality-of-life. For chronic tendinopathy recalcitrant to conservative approaches, percutaneous ultrasound tenotomy (PUT) has become a common minimally-invasive therapy. To clarify the histopathological effects of PUT, we assessed the cellular and tissue-level effects of PUT in an animal model of chronic tendinopathy.Design: This within-subject randomized-controlled study treated the bilateral Achilles’ tendons of 10 skeletally-mature, male New Zealand white rabbits with Kartogenin (KGN) beads to mimic chronic tendinopathy and allowed free cage activity for six weeks. One randomly-selected Achilles’ tendon per rabbit underwent sonographically-guided PUT, using 60 s of ultrasound energy. Six weeks post-procedure, the bilateral Achilles’ tendons were harvested and histologically graded.Results: Treated and untreated sides were compared using paired t-tests and mixed models. There were no statistically-significant differences in collagen arrangement, cellularity, or ground substance deposition (all p>0.16). Bonar scores for the most superficial level (95% CI) and the whole tendon (95% CI) were 1.7 (0.6, 2.8) and 0.9 (0.0, 1.9) points lower on the PUT side compared with the untreated side (p=0.037 and p=0.059 respectively). Conclusion: These findings provide evidence that PUT stimulates Histopathologic improvement in collagen formation and organization in the setting of chronic tendinopathy.

A Citation Analysis Study of the 50 Most-Cited Articles on the Achilles Tendon

Category: Other; Basic Sciences/Biologics Introduction/Purpose: Achilles tendon injuries represent one of the most common reasons of referral to orthopaedic surgeons. The purpose of this study was to determine the 50 most-cited articles on Achilles tendon pathologies in order to outline their characteristics, examine trends in publication and evaluate the correlation between citations and the quality of evidence. Methods: We searched Web of Science papers with the single keyword 'Achill*'. We identified and analyzed the top 50 most- cited articles and abstracted their characteristics. The methodological quality was assessed using the modified Coleman Methodology Score (mCMS). The correlation between the number of citations, the citation rate (citations/y), the impact factor of the journal for the year 2020 (JIF), the year of publication, the Level of Evidence (LoE), the type of study (tendon rupture, acute tendinopathy, chronic tendinopathy), the sample size and the mCMS was assessed through multiple bivariate analyses (Pearson or Spearman correlation coefficient). Results: Mean number of citations (+-SD) was 244 +- 88.8 (range, 657 to 157), with a total number of citations of 12.194 and a mean citation rate of 12.6 +- 5.4 (range, 28 to 3). The mean impact factor for the ten journals in which the 50 manuscripts were published was 5.1. The citation rate correlated with the number of citations (R=0.56, p&lt;0.001), the year of publication (R=0.60, p&lt;0.001) and the LoE (R=-0.37, p=0.022), but not with the citation rate (p=0.15). The year of publication correlated with the LoE as well (R=-0.43, p=0.008). Also, the quality of studies (in terms of mCMS) correlated with the impact factor of journals (R=0.35, p 0.03) and with the LoE (R=-0.48, p=0.003). Only 20 out of 39 primary studies (51%) had a prospective and comparative design, while 19 studies (48%) were classified as of poor quality (&lt; 50 points using the mCMS). Conclusion: Most-cited articles in the field of Achilles tendon injuries have generally been published on high-impact journals. Although the impact factor positively correlates with the quality of studies, their methodology is poor in almost half of cases. The average Level of Evidence provided by studies and their citation rate are both significantly increasing over time. Citation-based indicators do not represent robust measures of quality in studies dealing with Achilles tendon pathologies.

A Comparison of Minimally Invasive Achilles Repair Techniques on Functional Outcome and Failure Rates

Category: Sports; Ankle Introduction/Purpose: The incidence of Achilles tendon ruptures (ATR) is 21.5 per 100,000 people, making it the most common tendon rupture of the lower extremity. Repair methods consist of the traditional open, indirect repair with suture anchors (Midsubstance SpeedBridge, MSB), or jig-assisted technique (Percutaneous Achilles Repair System, PARS) with MSB; the latter two being minimally invasive. Early mobilization is crucial for restoration of tendon strength and function. The available literature shows minimally invasive techniques allow early weight-bearing but lacks the direct comparison of the techniques on clinical recovery duration and patient outcomes. The purpose of the study was to compare safety (i.e., risk of re-rupture) and efficiency (i.e., days to medical clearance) between the traditional open, MSB, and PARS with MSB techniques for ATR repair. Methods: This retrospective study used the CPT code 27650 and yielded 103 patients that underwent a primary ATR between 2017 to 2021 that were managed by three fellowship-trained orthopedic surgeons. After excluding chronic tendinopathy, revisions, patients lost to follow up or non-compliance, 41 acutely injured patients remained. Patients were followed until medical clearance or they reached Maximal Medical Improvement (MMI). The chart review included complications (e.g., infection, healing issues, nerve issues, re-rupture), referral to physical therapy (PT), days non-weight bearing (NWB), physical exam findings, and patient compliance with recommendations. Continuous variables were examined using one-way ANOVAs, one-way ANCOVAs, Independent-Samples Median Tests, or Kruskall-Wallis H Tests for age, body mass index (BMI), recovery duration, days NWB, and days until PT referral. Chi-square tests or Fisher's Exact tests were performed to compare proportions for sex, and complications. Bonferroni adjustments were performed for post hoc testing. Results: 41 patients (39.7 +- 24 years old; 38 males; 7 females) and BMI of 30.3 +- 6.1 kg/m2 underwent an ATR repair. There were no significant differences between groups for re-rupture rates (none reported), complications (P = 0.245), age (P = 0.497), or BMI (P = 0.908). There were significant differences in recovery duration (P = 0.004) and days NWB (P = 0.001). After controlling for days NWB, recovery duration was significantly different between groups [F(2,41) = 6.098, P = 0.005; partial h2 = 0234]. Recovery duration for PARS (119.2 +- 44.0 days) was significantly quicker than both open (169.4 +- 41.6 days; P = 0.019) and MSB (167.2 +- 31.2 days; P = 0.009), but no differences between open and MSB (P = 1.00). Conclusion: The PARS with MSB method had a much shorter recovery duration with clearance occurring 50 days faster than other techniques. It is possible the PARS with MSB technique allowed for earlier mobilization which contributed to an accelerated recovery. Non-weight bearing days and early initiation of PT could be a factor in recovery duration and warrants further exploration. Future prospective research with a more homogenous patient population with a focus on early rehabilitation will provide greater insight.

EFFECTIVENESS OF KINESIO INSTRUMENT ASSISTED SOFT TISSUE MOBILIZATION AND TAPING AMONG SPRINTERS WITH CHRONIC ACHILLES TENDINOPATHY

Background: Achilles tendinopathy is the most frequently reported injury related to the ankle and foot common in runners and other sports activity. Chronic tendinopathy most often characterized by tendon degeneration and the area can be painful to touch. As a result the tendon goes for spasm and joint stiffness due to the force generated during toe off of the ground during running and it is transmitted by achilles tendon. This may lead to affect the performance in sprinters. Aim: The aim of this study is to find the effectiveness of Kinesio instrument assisted soft tissue mobilization and taping among sprinters with chronic achilles tendinopathy. Method: The study included 30 sprinters from Chennai who fulfilled the inclusion criteria. The 20 meter yard test done to check the running performance for each sprinters and the pain was measured using numerical pain rating scale and functional disability was measured using lower extremity functional scale. Result: The results were analyzed using inferential statistics, t-test using intra-group analysis. The mean and standard deviation for 20-meter yard test 4.00 and 0.65. The mean and standard deviation for numeric pain rating scale will be 3.67 &amp;0.88. The mean and standard deviation of lower extremity functional scale will be 68.53 &amp; 6.11. The t- test for 20-meter, numeric pain rating scale &amp; lower extremity functional scale are 11.79, 10.93 &amp; 21.51. These have the significant at the level of p-valve = 0.000 &lt; 0.05. Conclusion: The present study concludes that there is a significant effective in Kinesio instrument assisted soft tissue mobilization followed by taping on ankle range of motion, performance level and functional disability with chronic achilles tendinopathy among sprinters.

Feasibility of Neovessel Embolization in a Large Animal Model of Tendinopathy: Safety and Efficacy of Various Embolization Agents.

Targeting neovessels in chronic tendinopathies has emerged as a new therapeutic approach and several embolization agents have been reported. The aim of this study was to investigate the feasibility of embolization with different agents in a porcine model of patellar tendinopathy and evaluate their safety and efficacy. Eight 3-month-old male piglets underwent percutaneous injection of collagenase type I to induce patellar tendinopathies (n = 16 tendons). They were divided into four groups (2 piglets, 4 tendons/group): the control group, 50–100 µm microspheres group, 100–300 µm microspheres group, and the Imipenem/Cilastatin (IMP/CS) group. Angiography and embolization were performed for each patellar tendon on day 7 (D7). The neovessels were evaluated visually with an angiography on day 14. The pathological analysis assessed the efficacy (Bonar score, number of neovessels/mm2) and safety (off-target persistent cutaneous ischemic modifications and presence of off-target embolization agents). The technical success was 92%, with a failed embolization for one tendon due to an arterial dissection. Neoangiogenesis was significantly less important in the embolized groups compared to the control group angiographies (p = 0.04) but not with respect to histology (Bonar score p = 0.15, neovessels p = 0.07). Off-target cutaneous embolization was more frequently depicted in the histology of the 50–100 µm microspheres group (p = 0.02). Embolization of this animal model with induced patellar tendinopathy was technically feasible with different agents and allowed assessing the safety and efficacy of neovessel destruction. Particles smaller than 100 µm seemed to be associated with more complications.

Opinion: Patient reported motivations for seeking stem cell therapy and considerations for counseling.

Stem cell therapies occupy a unique place in the American public's consciousness which has led to excessive enthusiasm over their potential to cure orthopedic conditions. Much has been written about direct-to-consumer marketing of cell therapies for a myriad of medical conditions. Far less has been studied on the attitudes that drive many patients to seek stem cell and orthobiologic therapies for musculoskeletal conditions. Previously published research on patient motivations for seeking stem cell therapy to treat orthopedic maladies such as osteoarthritis and chronic tendinopathies has shown that some patients were motivated by factors not supported by current medical evidence. These differing responses strongly suggest the need for patient-centered counseling to address misinformation about stem cell therapies for musculoskeletal conditions and increase health literacy about outcomes of orthobiologics.

956 Patient-Reported Outcomes After Platelet Rich Plasma Injections for Elbow Tendinopathies

Abstract Introduction Elbow tendinopathies affect 1–3% of the population, with 35–50 years old most commonly being affected. It is work-related as such can lead to significant morbidity, time off work, and affect the income of patients as well as daily activities. Non-operative management is the recommended first step however, success is influenced by patient compliance. Autologous platelet-rich plasma injections are a novel approach to managing tendinopathies however, evidence of efficacy was determined by NICE to be inadequate as such recommended more research into its use. Aim Assess patient-reported outcomes after PRP injections for management of elbow tendinopathies. Method Retrospective study of 28 patients with chronic elbow tendinopathies treated with PRP injections between 2018–2020. Pre-and Post-procedure outcomes were measured using the Oxford Elbow Score questionnaire. Average f/u duration-234 days. Results 27 patients answered the questionnaire out of 28 total patients that underwent the procedure. Of the 27 patients, 20 patients (74%) reported improvement in symptoms and were satisfied with their outcomes after one injection. Conclusions This study shows PRP injections are reasonable and efficient management for elbow tendinopathies in patients not managed medically. This helps strengthen arguments for PRP injections over steroids for tendinopathies as studies have shown that steroids have potential side effects, usually requires more than 1 injection for symptomatic relief and despite being beneficial in short term, is worse than other treatment options in the intermediate and long term for patients with tendinopathies. Our numbers also coincide with previous larger studies that showed ∼70% of patients reported symptoms improving after 1 injection.

Ex vivo study correlating the stiffness of the ovine patellar tendon to age and weight

ABSTRACT Tendons play a crucial role in the musculoskeletal system. In humans, tendon injuries, especially chronic tendinopathy, are very common and the patellar tendon is a frequent location for tendinopathy or injuries. The biomechanical characteristics of the patellar tendon, such as elasticity and stiffness, are of paramount importance and constitute major outcome measures in research studies. We aimed to assess whether the stiffness of the healthy ovine patellar tendon changes with age and weight in a population of normal animals. Sixty-eight ‘patella-patellar tendon-tibial tuberosity’ units from thirty-four Ile-de-France ewes of body mass 65 to 95 kg, euthanized for reasons other than musculoskeletal diseases, underwent a tensile test providing a measure of the tendon stiffness. Animals were sorted into three categories of age (1–2 yo, 3–5 yo, 6–10 yo). We found a positive but not significant correlation between age category and stiffness (r = 0.22, p = 0.27). There was a significantly positive correlation between weight and stiffness (r = 0.39, p = 0.04). In conclusion, the study characterized biomechanical properties of healthy tendons, provided useful reference values, and established the basis for future biomechanical tests on healing tendons in sheep. The most appropriate sheep population for those future studies would be non-overweight young adults presenting with no lameness.

Single cell multi-omics characterise discrete human tendon cells populations that persist in vitro and on fibrous scaffolds.

Chronic tendinopathy represents a growing healthcare burden in the ageing global population. Curative therapies remain elusive as the mechanisms that underlie chronic inflammation in tendon disease remain unclear. Identifying and isolating key pathogenic and reparative cells is essential in developing precision therapies and implantable materials for improved tendon healing. Multiple discrete human tendon cell populations have been previously described ex vivo. To determine if these populations persist in vitro, healthy human hamstring tenocytes were cultured for 8 d on either tissue culture plastic or aligned electrospun fibres of absorbable polydioxanone. Novel single-cell surface proteomics combined with unbiased single-cell transcriptomics (CITE-Seq) was used to identify discrete tenocyte populations. 6 cell populations were found, 4 of which shared key gene expression determinants with ex vivo human cell clusters: PTX3_PAPPA, POSTN_SCX, DCN_LUM and ITGA7_NES. Surface proteomics found that PTX3_PAPPA cells were CD10+CD26+CD54+. ITGA7_NES cells were CD146+ and POSTN_SCX cells were CD90+CD95+CD10+. Culture on the aligned electrospun fibres favoured 3 cell subtypes (DCN_LUM, POSTN_SCX and PTX3_ PAPPA), promoting high expression of tendon-matrix-associated genes and upregulating gene sets enriched for TNF-a and IL-6/STAT3 signalling. Discrete human tendon cell subpopulations persisted in in vitro culture and could be recognised by specific gene and surface-protein signatures. Aligned polydioxanone fibres promoted the survival of 3 clusters, including pro-inflammatory PTX3-expressing CD10+CD26+CD54+ cells found in chronic tendon disease. These results improved the understanding of preferred culture conditions for different tenocyte subpopulations and informed the development of in vitro models of tendon disease.

The effectiveness of percutaneous ultrasound-guided needle tenotomy compared to alternative treatments for chronic tendinopathy: a systematic review.

To compare percutaneous ultrasound-guided needle tenotomy (PUNT) to alternative treatments for chronic tendinopathy. A systematic literature search was performed with the following combination of keywords: ultrasound-guided, percutaneous, needling, tenotomy, Tenex, tendinopathy, and fasciotomy. Original studies comparing PUNT to alternative treatments for chronic tendinopathy were included in this systematic review. Twelve (n = 12) studies with 481 subjects were included. Two (2/12) articles compared PUNT to surgical tenotomy and concluded that PUNT provides the same outcomes as surgical tenotomy. Six (6/12) studies compared PUNT to platelet-rich plasma (PRP) injections, and two of them found both treatment modalities effective with no significant between-group differences. Three trials claimed that PUNT followed by PRP injections showed superior clinical outcomes compared to PUNT alone. However, the difference at long-term follow-up was statistically significant only in one of them. One study found PUNT superior to PUNT + PRP injection at short-term follow-up, although there were no between-group differences at long-term follow-up. Four (4/12) studies compared PUNT to steroid injection (SI) and showed that SI causes fast (2 weeks) but temporary pain relief, PUNT results in persistent but relatively slower improvement to SI, and the combined procedure has a more rapid and steady reduction in symptoms. PUNT is an effective treatment technique for chronic tendinopathy and should be considered when non-invasive treatments have failed. Effects of PRP and SI are transient and dissipate over time and do not contribute to long-term outcome.