Extracorporeal shock waves promote healing of collagenase-induced Achilles tendinitis and increase TGF-beta1 and IGF-I expression

Staying in the Game: Interventions for Managing Achilles Tendinopathy in the In-Season Athlete

ABSTRACT

Achilles tendinopathy is a common overuse injury that is traditionally managed with activity modification and a progressive eccentric strengthening program. This narrative review describes the available evidence for adjunctive procedural interventions in the management of midportion and insertional AT, specifically in the athletic population. Safety and efficacy data from available literature on extracorporeal shockwave therapy, platelet-rich plasma, high-volume injectate with or without tendon scraping, and percutaneous needle tenotomy are used to propose an algorithm for treatment of Achilles tendinopathy for the in-season athlete.

Predictive Prognostic Factors in Non-Calcific Supraspinatus Tendinopathy Treated with Focused Extracorporeal Shock Wave Therapy: An Artificial Neural Network Approach

The supraspinatus tendon is one of the most involved tendons in the development of shoulder pain. Extracorporeal shockwave therapy (ESWT) has been recognized as a valid and safe treatment. Sometimes the symptoms cannot be relieved, or a relapse develops, affecting the patient's quality of life. Therefore, a prediction protocol could be a powerful tool aiding our clinical decisions. An artificial neural network was run, in particular a multilayer perceptron model incorporating input information such as the VAS and Constant-Murley score, administered at T0 and at T1 after six months. It showed a model sensitivity of 80.7%, and the area under the ROC curve was 0.701, which demonstrates good discrimination. The aim of our study was to identify predictive factors for minimal clinically successful therapy (MCST), defined as a reduction of ≥40% in VAS score at T1 following ESWT for chronic non-calcific supraspinatus tendinopathy (SNCCT). From the male gender, we expect greater and more frequent clinical success. The more severe the patient's initial condition, the greater the possibility that clinical success will decrease. The Constant and Murley score, Roles and Maudsley score, and VAS are not just evaluation tools to verify an improvement; they are also prognostic factors to be taken into consideration in the assessment of achieving clinical success. Due to the lower clinical improvement observed in older patients and those with worse clinical and functional scales, it would be preferable to also provide these patients with the possibility of combined treatments. The ANN predictive model is reasonable and accurate in studying the influence of prognostic factors and achieving clinical success in patients with chronic non-calcific tendinopathy of the supraspinatus treated with ESWT.

Use of extracorporeal shockwave therapies for athletes and physically active individuals: a systematic review

OBJECTIVE

To determine the efficacy of extracorporeal shockwave therapy (ESWT) and investigate outcomes following the use of ESWT for athletes and physically active individuals.

DESIGN

Systematic review.

DATA SOURCES

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and searched four databases: PubMed (NLM), Embase (Elsevier), CINAHL Complete (EBSCO) and Web of Science (Clarivate).

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Included studies were randomised controlled trials, cohort and case-control studies, cases series and reports that evaluated outcomes following ESWT for athletes, physically active individuals and occupational groups requiring regular physical activity such as military cadets.

RESULTS

56 studies with 1874 athletes or physically active individuals were included. Using the Oxford level of evidence rating, included studies were 18 level I (32.1%), 3 level II (5.4%), 10 level III (17.9%), 13 level IV (23.2%) and 12 level V (21.4%). Based on the level I studies, ESWT may be effective alone in plantar fasciitis, lateral epicondylitis and proximal hamstring tendinopathy and as an adjunct to exercise treatment in medial tibial stress syndrome and osteitis pubis in athletes or physically active individuals. In most studies, athletes were allowed to continue activities and training and tolerated ESWT with minimal side effects.

CONCLUSION

ESWT may offer an efficacious treatment alone or as an adjunct to concurrent exercise therapy in selected sports-related injuries and without major adverse events. Further high-level research is needed to better define the role and clinical outcomes of ESWT.

Efficacy of radial shock wave therapy on rat models of adjuvant arthritis

BACKGROUND

Extracorporeal shock wave therapy (ESWT) is an effective treatment for musculoskeletal pain, tendinopathy, and fasciitis with an anti-inflammatory effect. ESWT can be categorized into two groups: radial pressure wave (RPW) and focused shock wave (FSW). Although there have been several studies on the inflammation and pain-improvement mechanisms of FSW, there are few studies on the pain-improvement mechanisms of RPW. This study aimed to elucidate the efficacy of RPW in a rat model of adjuvant arthritis.

METHODS

Ninety-six rats were randomly categorized into three groups: RPW, control, and sham as follows: (I) RPW group, which received RPW application after complete Freund's adjuvant (CFA) injection; (II) Control group, which received only CFA injection; and (III) Sham group, which received only saline injection. All rats were evaluated at 0, 4, 7, 14, 28, and 56 days post-RPW application based on foot circumference, von Frey test, and immunohistochemistry of nerve fibers for calcitonin gene-related peptide (CGRP) and protein gene product (PGP) 9.5 in plantar skins.

RESULTS

There were no significant differences in foot circumference between the RPW and control groups at any time point. The RPW group showed significant improvements in the von Frey test results on days 7 and 14. The total CGRP-immunoreactive (ir) and PGP9.5-ir nerve fiber lengths in the RPW group decreased on day 0; however, both were increased in the control group. The CGRP-ir and PGP9.5-ir nerve fibers in the RPW group were significantly shorter than those in the control group until day 14 after RPW.

CONCLUSIONS

RPW improved the mechanical hypersensitivity between days 7 and 14 after application. Like FSW, RPW also induced the degeneration of sensory nerve fibers in the skin in the early period after irradiation, and reinnervation occurred between 14 and 28 days. Thus, our results demonstrate one of the pain relief mechanisms after RPW application.

Polydeoxyribonucleotide and Shock Wave Therapy Sequence Efficacy in Regenerating Immobilized Rabbit Calf Muscles

This study primarily aimed to investigate the combined effects of polydeoxyribonucleotide (PDRN) and extracorporeal shock wave therapy (ESWT) sequences on the regenerative processes in atrophied animal muscles. Thirty male New Zealand rabbits, aged 12 weeks, were divided into five groups: normal saline (Group 1), PDRN (Group 2), ESWT (Group 3), PDRN injection before ESWT (Group 4), and PDRN injection after ESWT (Group 5). After 2 weeks of cast immobilization, the respective treatments were administered to the atrophied calf muscles. Radial ESWT was performed twice weekly. Calf circumference, tibial nerve compound muscle action potential (CMAP), and gastrocnemius (GCM) muscle thickness after 2 weeks of treatment were evaluated. Histological and immunohistochemical staining, as well as Western blot analysis, were conducted 2 weeks post-treatment. Staining intensity and extent were assessed using semi-quantitative scores. Groups 4 and 5 demonstrated significantly greater calf muscle circumference, GCM muscle thickness, tibial nerve CMAP, and GCM muscle fiber cross-sectional area (type I, type II, and total) than the remaining three groups (p < 0.05), while they did not differ significantly in these parameters. Groups 2 and 3 showed higher values for all the mentioned parameters than Group 1 (p < 0.05). Group 4 had the greatest ratio of vascular endothelial growth factor (VEGF) to platelet endothelial cell adhesion molecule-1 (PECAM-1) in the GCM muscle fibers compared to the other four groups (p < 0.05). Western blot analysis revealed significantly higher expression of angiogenesis cytokines in Groups 4 and 5 than in the other groups (p < 0.05). The combination of ESWT and PDRN injection demonstrated superior regenerative efficacy for atrophied calf muscle tissue in rabbit models compared to these techniques alone or saline. In particular, administering ESWT after PDRN injection yielded the most favorable outcomes in specific parameters.

Ultrasonographic appearance of supraspinatus and biceps tendinopathy improves in dogs treated with low-intensity extracorporeal shock wave therapy: a retrospective study

Objective

This study aimed to determine whether dogs with shoulder tendinopathy diagnosed via musculoskeletal ultrasound would show improvement in imaging after treatment using piezoelectric shockwave therapy and rest.

Methods

Medical records were reviewed for dogs diagnosed with biceps and/or supraspinatus tendinopathy via musculoskeletal ultrasound, treated using piezowave shockwave, and re-imaged post-treatment. Data collected included patient signalment, duration and grade of lameness, prior rest, piezowave dose, and patient outcome, including a return to sport where applicable. Images were scored using an adapted ultrasound grading scale, in addition to obtaining cross-sectional area measurements. Statistics included Shapiro-Wilk tests (normality), Wilcoxon matched pairs signed rank tests (pre- vs. post-treatment comparisons), and Spearman's correlation coefficients (lameness grade vs. ultrasound score) (significant at P < 0.05).

Results

In total, 26 of 30 dogs had pathology involving both the biceps and supraspinatus tendons in one limb, with 27 of 30 having tendon/s affected bilaterally. For both tendons, post-treatment cross-sectional area and ultrasound score were significantly lower than pre-treatment (P < 0.001). Lameness decreased clinically (P < 0.0001) following piezowave shockwave treatment regardless of the tendons involved, but the lameness score did not correlate with the ultrasound score for either tendon.

Conclusion

Dogs with tendinopathy of the biceps brachii and supraspinatus showed significant improvement on follow-up musculoskeletal ultrasound and lameness evaluation after the treatment of their tendons using piezoelectric shockwave therapy with rest.

Clinical significance

Canine biceps brachii and supraspinatus tendinopathy can cause variable lameness and ultrasonographic appearance, which improves after shockwave therapy and rest. The ultrasound scoring system and cross-sectional area assessment provide useful outcome measures for clinical cases.

The effects and underlying mechanism of extracorporeal shockwave therapy on fracture healing

The clinical efficacy of ESWT in treating bone non union has been widely recognized, but the biological mechanism of ESWT promoting bone non union healing is still unclear. ESWT can make old callus micro fracture through mechanical conduction, form subperiosteal hematoma, promote the release of bioactive factors, reactivate the fracture healing mechanism, rebalance the activities of osteoblasts and osteoclast, promote the angiogenesis of fracture site, and accelerate the healing of bone nonunion.Over recent years, great efforts have been made by both scientists and clinicians to explore the underlying mechanism behind the healing effect of ESWT on bone fractures. In this review, we introduced the growth factors during osteogenesis induced by ESWT hoping to provide new insights in the clinical use of ESWT.

Analysis of the 50 Most Cited Articles on Achilles Tendon Injury

Background

Achilles tendon injuries represent one of the most common reasons for referral to orthopaedic surgeons.

Purpose

To outline the characteristics, examine trends in publication, and evaluate the correlation between citations and study quality of the 50 most cited articles on Achilles tendon injury.

Study Design

Cross-sectional study.

Methods

After searching the Web of Science for articles published in orthopaedic journals, we identified the 50 most cited articles on Achilles tendon injury and abstracted their characteristics. Risk of bias was assessed using the modified Coleman Methodology Score (mCMS). Multiple bivariate analyses (Pearson or Spearman correlation coefficient) were used to evaluate the association among number of citations, citation rate (citations/year), 2020 journal impact factor (JIF), year of publication, level of evidence (LoE), study type (tendon rupture or chronic tendinopathy), sample size, and mCMS.

Results

The top 50 articles were cited 12,194 times. Each article had a mean ± SD 244 ± 88.8 citations (range, 157-657) and a citation rate of 12.6 ± 5.4 per year (range, 3-28). A total of 35 studies (70%) were published between 2000 and 2010. The citation rate of the 16 most recent studies was almost double that of the 16 oldest studies (17.5 vs 9.9; P < .001). Nineteen studies (49%) were classified as having poor quality (mCMS <50 points). The mean JIF of the 9 journals that published the studies was 5.1. The citation rate correlated with the number of citations (r = 0.56; P < .001), publication year (r = 0.60; P < .001), and LoE (r = -0.44; P = .005). The publication year correlated with the LoE (r = -0.40; P = .01). Study quality in terms of mCMS correlated with the JIF (r = 0.35; P = .03) and LoE (r = -0.48; P = .003) but not the citation rate (P = .15).

Conclusion

The mean LoE and the citation rate of the most cited articles on Achilles tendon injury both significantly increased over time. Although the JIF was positively correlated with study quality, almost half of the studies had poor-quality methodology.

Utilizing Extracorporeal Shockwave Therapy for in-Season Athletes

An athlete’s health and availability to train and compete at an optimal performance level is a growing focus for professional sports organizations [...]

External stimulation: A potential therapeutic strategy for tendon-bone healing

Injuries at the tendon-bone interface are very common in the field of sports medicine, and healing at the tendon-bone interface is complex. Injuries to the tendon-bone interface can seriously affect a patient’s quality of life, so it is essential to restore stability and promote healing of the tendon-bone interface. In addition to surgical treatment, the healing of tendons and bones can also be properly combined with extracorporeal stimulation therapy during the recovery process. In this review, we discuss the effects of extracorporeal shock waves (ESWs), low-intensity pulsed ultrasound (LIPUS), and mechanical stress on tendon-bone healing, focusing on the possible mechanisms of action of mechanical stress on tendon-bone healing in terms of transcription factors and biomolecules. The aim is to provide possible therapeutic approaches for subsequent clinical treatment.

Leucine rich repeat containing 32 accelerates tenogenic differentiation of tendon-derived stem cells and promotes Achilles tendon repair in rats

Although many surgical or non-operative therapies have been developed to treat Achilles tendon injuries, the prognosis of which is often unsatisfactory. Recently, biologic approaches using multipotent stem cells like tendon-derived stem cells (TDSCs) pose a possible treatment option. To evaluate whether the Leucine rich repeat containing 32 (Lrrc32) affects the tenogenic differentiation of TDSCs and thus promotes Achilles tendon healing. TDSCs were infected with the recombinant Lrrc32-overexpressing lentivirus (LV-Lrrc32) and then locally injected into the injured site of rat. Four weeks after surgery, the Achilles tendon tissue (~0.5 cm) around the injured area was harvested for analysis. Pathological results showed that Lrrc32-overexpressing TDSCs significantly improved the morphological changes of the injured tendons. Specifically, the increased collagen-I expression and hydroxyproline content in extracellular matrix, and more orderly arrangement of the regenerated collagen fibers were observed in the Lrrc32 overexpression group. Moreover, 4 weeks after injection of Lrrc32-overexpressing TDSCs, the expression of tenocyte-related genes such as tenomodulin (Tnmd), scleraxis (Scx) and decorin (Dcn) were upregulated in the area of the healing tendon. These findings indicated that Lrrc32 promoted the tenogenic differentiation of TDSCs in vivo. Additionally, Lrrc32 overexpression also increased the expression of TGF-β1 and p-SMAD2/3, suggesting that the beneficial effects of Lrrc32 on tendon repair might be associated with the expression of TGF-β1 and p-SMAD2/3. Our findings collectively revealed that Lrrc32-overexpressed TDSCs promoted tendon healing more effectively than TDSCs alone.

Biological effects of extracorporeal shockwave therapy in tendons: A systematic review

Extracorporeal shockwave therapy was initially used for kidney stone disintegration and its application was then extended to calcific tendinitis. The therapeutic field expanded and included numerous types of tendinopathies, from shoulder to plantar fascia. The clinical benefits were documented in trials and the effects and mechanisms were studied on models including animal and human tendons. The present systematic review outlines a large spectrum of biological effects. First, an optimal dose is adapted for each species and each tendon; exceeding the optimal dose may lead to structural injury. Furthermore, the biological effects may be grouped into neovascularization induction, cellularity and extracellular matrix changes, metalloprotease and cytokine modulation, as well as lubricin production. As a result, the remodeled tendon displays improved biomechanical properties to resist stress.

Hamstring Injuries: Critical Analysis Review of Current Nonoperative Treatments

➢

Hamstring injuries are common among active and athletic individuals, especially those involved in high-speed running, distance running, or sports requiring sudden directional changes. Acute hamstring strains often occur as an eccentric strain during running or a stretch-type injury caused by simultaneous hip flexion and knee extension. Proximal hamstring tendinopathy is an overuse injury of the hamstring tendon as a result of chronic cicatrization of the musculotendinous unit.

➢

Repeated stress to the hamstring tendon leads to increased cellularity of tendon fibers, disruption of collagen, and subsequent microinjury of the tissue that attaches the tendon to bone.

➢

Management of hamstring injuries generally begins with nonoperative modalities consisting of eccentric rehabilitative exercise programs. Although various other treatment modalities are available, the comparative efficacy of these supportive measures is not well differentiated at this time.

➢

In this article, we review the current literature with regard to the nonoperative treatment of hamstring injuries, specifically focusing on acute hamstring muscle strains and proximal hamstring tendinopathy in order to provide supplementary insight on the effectiveness of current modalities.

Case study: Treating infraspinatus and supraspinatus trigger points and supraspinatus tendinopathy utilizing piezoelectric shockwave

Two individual case studies demonstrate piezoelectric shockwave treatment for the resolution of a supraspinatus tendinopathy and supraspinatus and infraspinatus myofascial trigger points (MTPs) via musculoskeletal ultrasound. This is the first documentation of improvement of both tendon and muscle fiber patterns in canine patients treated with piezoelectric shockwave. These cases validate the use of piezoelectric shockwave during the rehabilitation of common canine shoulder injuries.

Biological response of extracorporeal shock wave therapy to tendinopathy in vivo (review)

Tendinopathy is a degenerative disease of the tendons caused by prolonged overstretching or overuse of the tendons. It accounts for a large proportion of musculoskeletal disorders which can occur in all age groups. The management of tendinopathy is typically conservative. In clinical practice, when other conservative treatments fail, extracorporeal shock wave therapy (ESWT) is normally used as an efficient alternative to surgical management. Several basic studies have shown that ESWT with lower energy flux densities can produce some biological responses in vivo to tendinopathy and may accelerate the initiation of the healing process in injured tendons. ESWT has a positive impact on the interactive chain of biological response, enhancing the signaling pathways of angiogenesis through mechanical conduction, and promoting cell proliferation and collagen formation. Finally, it helps tissue regeneration by controlling inflammation. The purpose of this review is to summarize the biological responses generated by ESWT in tendinopathy through a comprehensive review of the published literature. Although ESWT has been used clinically for the treatment of tendinopathies for nearly decades, less is known about the experimental studies of its biological effects on tendon tissue. Further studies on the biological response of ESWT for tendon injuries in vivo are needed in the future in order to provide better management to patients.

Comparative Efficacy of Nonoperative Treatments for Greater Trochanteric Pain Syndrome: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

An evolved understanding of the pathophysiology of greater trochanteric pain syndrome has led to a number of proposed nonoperative management strategies. The objective of this review was to compare the efficacy of the various nonoperative treatments for greater trochanteric pain syndrome (GTPS).

DESIGN

Systematic review and network meta-analysis.

SETTING

PubMed, Embase, CENTRAL, SCOPUS, and Web of Science were searched to January 2020.

PATIENTS

Patients undergoing nonoperative treatment for GTPS.

INTERVENTIONS

Nonoperative treatment strategies for GTPS including injections of corticosteroids, platelet-rich plasma, hyaluronic acid, dry needling, and structured exercise programs and extracorporeal shockwave therapy.

MAIN OUTCOME MEASURES

Pain and functional outcomes. Bayesian random-effects model was performed to assess the direct and indirect comparison of all treatment options.

RESULTS

Thirteen randomized controlled trials and 1034 patients were included. For pain scores at 1 to 3 months follow-up, both platelet-rich plasma (PRP) and shockwave therapy demonstrated significantly better pain scores compared with the no treatment control group with PRP having the highest probability of being the best treatment at both 1 to 3 months and 6 to 12 months. No proposed therapies significantly outperformed the no treatment control group for pain scores at 6 to 12 months. Structured exercise had the highest probability of being the best treatment for improvements in functional outcomes and was the only treatment that significantly improved functional outcome scores compared with the no treatment arm at 1 to 3 months.

CONCLUSION

Current evidence suggests that PRP and shockwave therapy may provide short-term (1-3 months) pain relief, and structured exercise leads to short-term (1-3 months) improvements in functional outcomes.

Molecular Mechanisms Underlying the Pain-Relieving Effects of Extracorporeal Shock Wave Therapy: A Focus on Fascia Nociceptors

In recent years, extracorporeal shock wave therapy (ESWT) has received increasing attention for its potential beneficial effects on various bone and soft-tissue pathologies, yielding promising outcomes for pain relief and functional recovery. In fact, ESWT has emerged as an alternative, non-invasive, and safe treatment for the management of numerous musculoskeletal disorders, including myofascial pain syndrome (MPS). In particular, MPS is a common chronic painful condition, accounting for the largest proportion of patients affected by musculoskeletal problems. Remarkably, sensory innervation and nociceptors of the fascial system are emerging to play a pivotal role as pain generators in MPS. At the same time, increasing evidence demonstrates that application of ESWT results in selective loss of sensory unmyelinated nerve fibers, thereby inducing long-lasting analgesia. The findings discussed in the present review are supposed to add novel viewpoints that may further enrich our knowledge on the complex interactions occurring between disorders of the deep fascia including changes in innervation, sensitization of fascial nociceptors, the pathophysiology of chronic musculoskeletal pain of MPS, and EWST-induced analgesia. Moreover, gaining mechanistic insights into the molecular mechanisms of pain-alleviating effects of ESWT may broaden the fields of shock waves clinical practice far beyond the musculoskeletal system or its original application for lithotripsy.

Cardiac Shockwave Therapy – A Novel Therapy for Ischemic Cardiomyopathy?

Over the past decades, shockwave therapy (SWT) has gained increasing interest as a therapeutic approach for regenerative medicine applications, such as healing of bone fractures and wounds. More recently, pre-clinical studies have elucidated potential mechanisms for the regenerative effects of SWT in myocardial ischemia. The mechanical stimulus of SWT may induce regenerative effects in ischemic tissue via growth factor release, modulation of inflammatory response, and angiogenesis. Activation of the innate immune system and stimulation of purinergic receptors by SWT appears to enhance vascularization and regeneration of injured tissue with functional improvement. Intriguingly, small single center studies suggest that SWT may improve angina, exercise tolerance, and hemodynamics in patients with ischemic heart disease. Thus, SWT may represent a promising technology to induce cardiac protection or repair in patients with ischemic heart disease.

The Effects of the Exposure of Musculoskeletal Tissue to Extracorporeal Shock Waves

Extracorporeal shock wave therapy (ESWT) is a safe and effective treatment option for various pathologies of the musculoskeletal system. Many studies address the molecular and cellular mechanisms of action of ESWT. However, to date, no uniform concept could be established on this matter. In the present study, we perform a systematic review of the effects of exposure of musculoskeletal tissue to extracorporeal shock waves (ESWs) reported in the literature. The key results are as follows: (i) compared to the effects of many other forms of therapy, the clinical benefit of ESWT does not appear to be based on a single mechanism; (ii) different tissues respond to the same mechanical stimulus in different ways; (iii) just because a mechanism of action of ESWT is described in a study does not automatically mean that this mechanism is relevant to the observed clinical effect; (iv) focused ESWs and radial ESWs seem to act in a similar way; and (v) even the most sophisticated research into the effects of exposure of musculoskeletal tissue to ESWs cannot substitute clinical research in order to determine the optimum intensity, treatment frequency and localization of ESWT.

Comparison of Extracorporeal Shockwave Therapy and Blind Steroid Injection in Patients With Coccydynia: A Randomized Clinical Trial

OBJECTIVE

Extracorporeal shockwave therapy (ESWT) emerged recently for the treatment of musculoskeletal conditions owing to its regenerative and anti-inflammatory effects. In this study, the aim was to compare the efficacies of ESWT and steroid injection in patients with coccydynia.

DESIGN

Thirty-four patients with coccydynia were randomized into two groups. In the ESWT group, patients received radial shockwave for three weekly sessions. The second treatment group received an injection of steroid in the tip of the coccyx or sacrococcygeal junction. Outcome measures were visual analog scale, Short-Form Health Survey, and Dallas Pain Questionnaire. Visual analog scale was measured at baseline and 1 wk, 1 mo, 2 mos, and 6 mos after the intervention. Short-Form Health Survey and Dallas Pain Questionnaire were assessed before and 1 mo after treatment.

RESULTS

The visual analog scale score was significantly decreased in all follow-ups in both groups. There was also a significant decrease between 1 wk and three other posttreatment visits in the ESWT treatment group. Time and group interaction effect was significant on the visual analog scale (F2.64, 84.63 = 2.95, P = 0.043), in favor of ESWT. Concerning the Short-Form Health Survey and Dallas Pain Questionnaire, only some dimensions improved.

CONCLUSIONS

ESWT is an effective intervention in patients with coccydynia and had more long-lasting efficacy than steroid in terms of pain relief over 6 mos of observation.

17β-Estradiol attenuates inflammation and tendon degeneration in a rat model of Achilles tendinitis

INTRODUCTION

17β-Estradiol (E2) is an immune-regulatory agent with anti-inflammatory effects. However, it is still unknown whether E2 exerts pharmacological properties against Achilles tendinitis (AT). This study aims to investigate the effects of E2 on AT and its underlying mechanisms.

MATERIALS AND METHODS

The established model of Achilles tendinitis was intraperitoneally injected with E2 (10, 20, or 30 μg/kg/d). After 8 weeks, biomechanical properties of the Achilles tendon were determined. Hydroxyproline content and tendon degeneration-related biomarkers were determined. The levels of inflammatory cytokines and apoptotic-related biomarkers in tendon tissues were determined. Furthermore, western blotting was determined to detect the expressions of ER-α and the PI3K/Akt pathway in tendon tissues.

RESULTS

E2 relieved AT-related symptoms in a dose-dependent manner. E2 ameliorated tendon degeneration by regulating tendon degeneration-related biomarkers (e.g., collagen type I and III, Decorin (DCN), and tenascin-C). Besides, treatment with E2 suppressed inflammatory cytokines and increased anti-inflammatory cytokines. Treatment with E2 also regulated cell apoptosis in tendon tissues. The underlying mechanism study revealed that treatment with E2 activated ER-α and upregulated the PI3K/Akt pathway.

CONCLUSION

The regulatory effects of E2 on inflammation and tendon degeneration in a rat model of AT were associated with the ER-α and the PI3K/Akt signaling pathways.

Analgesic Effect of Extracorporeal Shock-Wave Therapy in Individuals with Lateral Epicondylitis: A Randomized Controlled Trial

This study was conducted to investigate the effect of extracorporeal shock-wave therapy (ESWT) on pain, grip strength, and upper-extremity function in lateral epicondylitis. A sample of 40 patients with LE (21 males) was randomly allocated to either the ESWT experimental (n = 20) or the conventional-physiotherapy control group (n = 20). All patients received five sessions during the treatment program. The outcome measures used were the Visual Analog Scale (VAS), the Taiwan version of the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire, and a dynamometer (maximal grip strength). Forty participants completed the study. Participants in both groups improved significantly after treatment in terms of VAS (pain reduced), maximal grip strength, and DASH scores. However, the pain was reduced and upper-extremity function and maximal grip strength were more significantly improved after ESWT in the experimental group. ESWT has a superior effect in reducing pain and improving upper-extremity function and grip strength in people with lateral epicondylitis. It seems that five sessions of ESWT are optimal to produce a significant difference. Further studies are strongly needed to verify our findings.

Patellar Tendinopathy: Critical Analysis Review of Current Nonoperative Treatments

»

Patellar tendinopathy is an attritional injury of the patellar tendon that is frequently identified in jumping athletes. Through repetitive or explosive movements, considerable loads and high peak strains are generated across the patellar tendon.

»

This leads to microinjury of tendon fibers, local mucoid degeneration, and loss of the fibrocartilaginous tissue that attaches tendon to bone.

»

Management of patellar tendinopathy often begins with nonoperative modalities: progressive tendon loading and eccentric rehabilitative exercise programs are the most effective. While a variety of additional treatment modalities are available, the comparative efficacy of these supportive treatments is not well differentiated at this time.

»

In this article, we analyze the existing literature regarding nonoperative treatment of patellar tendinopathy and provide additional insight on the effectiveness of current modalities.

Mechanical Properties of Animal Tendons: A Review and Comparative Study for the Identification of the Most Suitable Human Tendon Surrogates

The mechanical response of a tendon to load is strictly related to its complex and highly organized hierarchical structure, which ranges from the nano- to macroscale. In a broader context, the mechanical properties of tendons during tensile tests are affected by several distinct factors, due in part to tendon nature (anatomical site, age, training, injury, etc.) but also depending on the experimental setup and settings. This work aimed to present a systematic review of the mechanical properties of tendons reported in the scientific literature by considering different anatomical regions in humans and several animal species (horse, cow, swine, sheep, rabbit, dog, rat, mouse, and foal). This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method. The literature research was conducted via Google Scholar, PubMed, PicoPolito (Politecnico di Torino’s online catalogue), and Science Direct. Sixty studies were selected and analyzed. The structural and mechanical properties described in different animal species were reported and summarized in tables. Only the results from studies reporting the strain rate parameter were considered for the comparison with human tendons, as they were deemed more reliable. Our findings showed similarities between animal and human tendons that should be considered in biomechanical evaluation. An additional analysis of the effects of different strain rates showed the influence of this parameter.

Current understanding of the diagnosis and management of the tendinopathy: An update from the lab to the clinical practice

Tendinopathy is labeled by many authors as a troublesome, common pathology, present in up to 30% medical care consultations involving musculoskeletal conditions. Despite the lasting interest for addressing tendon pathology, current researchers agree that even the exact definition of the term tendinopathy is unclear. Tendinopathy is currently diagnosed as a clinical hypothesis based on the patient symptoms and physical context. One of the main goals of current clinical management is to personalize treatment approaches to adapt them to the many different needs of the population. Tendons are complex structures that unite muscles and bones with two main objectives: to transmit forces and storage and release energy. Regarding the tensile properties of the tendons, several authors argued that tendons have higher tensile strength compared with muscles, however, are considered less flexible. Tendinopathy is an accepted term which is used to indicated a variety of tissue conditions that appear in injured tendons and describes a non-rupture damage in the tendon or paratendon, which is intensified with mechanical loading Even when the pathoetiology of tendinopathy is unclear, there is a wide array of treatments available to treat and manage tendinopathy. Although tendinitis usually debuts with an inflammatory response, the majority of chronic tendinopathies do not present inflammation and so the choosing of treatment should vary depending on severity, compliance, pain and duration of symptoms. The purpose of this article is to review and provide an overview about the currently research of the tendon diagnosis, management and etiology.

Cell autonomous TGFβ signaling is essential for stem/progenitor cell recruitment into degenerative tendons

Understanding cell recruitment in damaged tendons is critical for improvements in regenerative therapy. We recently reported that targeted disruption of transforming growth factor beta (TGFβ) type II receptor in the tendon cell lineage (Tgfbr2^ScxCre) resulted in resident tenocyte dedifferentiation and tendon deterioration in postnatal stages. Here we extend the analysis and identify direct recruitment of stem/progenitor cells into the degenerative mutant tendons. Cre-mediated lineage tracing indicates that these cells are not derived from tendon-ensheathing tissues or from a Scleraxis-expressing lineage, and they turned on tendon markers only upon entering the mutant tendons. Through immunohistochemistry and inducible gene deletion, we further find that the recruited cells originated from a Sox9-expressing lineage and their recruitment was dependent on cell autonomous TGFβ signaling. The cells identified in this study thus differ from previous reports of cell recruitment into injured tendons and suggest a critical role for TGFβ signaling in cell recruitment, providing insights that may support improvements in tendon repair.

•

Targeted deletion of TGFβ signaling led to degenerative changes in mouse tendons

•

Stem/progenitor cells were recruited into the degenerative mutant tendons

•

The recruited cells are different from the ones so far reported in tendon injury

•

Recruitment was dependent on cell autonomous TGFβ signaling in the recruited cells

Extracorporeal Shockwave Therapy in the Management of Sports Medicine Injuries

ABSTRACT

Treatment of musculoskeletal conditions in athletes with extracorporeal shockwave therapy (ESWT) is gaining popularity as greater evidence supports its use. ESWT protocols (describing energy flux density, number of impulses, type of shockwave (focused or radial), number/frequency/duration of treatment session, area of application, and postprocedural therapy protocols) can be adjusted in the clinical setting. Protocols vary across studies, and optimal protocols for most indications are yet to be determined. ESWT can safely be used to treat various musculoskeletal conditions in athletes, including rotator cuff tendinopathy, lateral elbow epicondlyopathy, greater trochanteric pain syndrome, hamstring tendinopathy, patellar tendinopathy, Achilles tendinopathy, other tendinopathies, plantar fasciopathy, bone stress injuries, and medial tibial stress syndrome. ESWT can be used to treat in-season athletes, as it often requires no/minimal time away from sport and may result in rapid benefits. ESWT should be used in conjunction with physical therapy to facilitate longer-term gains in function and to optimize healing.

Overexpression of mechanical sensitive miR-337-3p alleviates ectopic ossification in rat tendinopathy model via targeting IRS1 and Nox4 of tendon-derived stem cells

Tendinopathy, which is characterized by the ectopic ossification of tendon, is a common disease occurring in certain population, such as athletes that suffer from repetitive tendon strains. However, the molecular mechanism underlying the pathogenesis of tendinopathy caused by the overuse of tendon is still lacking. Here, we found that the mechanosensitive miRNA, miR-337-3p, had lower expression under uniaxial cyclical mechanical loading in tendon-derived stem cells (TDSCs) and negatively controlled chondro-osteogenic differentiation of TDSCs. Importantly, downregulation of miR-337-3p expression was also observed in both rat and human calcified tendons, and overexpressing miR-337-3p in patellar tendons of rat tendinopathy model displayed a robust therapeutic efficiency. Mechanistically, we found that the proinflammatory cytokine interleukin-1β was the upstream factor of miR-337-3p that bridges the mechanical loading with its downregulation. Furthermore, the target genes of miR-337-3p, NADPH oxidase 4, and insulin receptor substrate 1, activated chondro-osteogenic differentiation of TDSCs through JNK and ERK signaling, respectively. Thus, these findings not only provide novel insight into the molecular mechanisms underlying ectopic ossification in tendinopathy but also highlight the significance of miR-337-3p as a putative therapeutic target for clinic treatment of tendinopathy.

Predictive factors of response in radial Extracorporeal Shock-waves Therapy for Myofascial and Articular Pain: A retrospective cohort study

BACKGROUND

Myofascial Pain Syndrome causes disability in daily life activities and despite all efforts, it continues to be a challenge, perpetuating suffering, overloading services and costs. New treatment options need to be tested.

OBJECTIVE

We aimed to quantify the rESWT short-term analgesic effect and identify the predictors of success through comparing results achieved in MPS and Articular Pain (AP).

METHOD

Retrospective cohort study of 1,580 patients with Myofascial Pain Syndrome or Articular Pain underwent two weekly radial Extracorporeal Shock-wave Therapy sessions. The pain intensity was measured by Visual Analog Scale before and one week after the end of the treatment (3 weeks).

RESULTS

The therapy decreases pain by 62.50% (p< 0.0001), with a high success rate (91.59%) and a low worsening of baseline conditions rate (2.1%). The best recommendation is for patients with intense myofascial pain (Visual Analog Scale ⩾ 70 mm), using high shock-wave frequency (⩾ 15 Hz).

CONCLUSIONS

Two rESWT sessions promote pain relief, with a high success rate and low rates of treatment abandonment and worsening. The best results are obtained in myofascial pain patients with high pain intensity, treated with high-frequency dosage.

Gene transcripts expressed in equine white blood cells are potential biomarkers of extracorporeal shock wave therapy

Extracorporeal shockwave therapy (ESWT) is a treatment applied to musculoskeletal injuries in equine athletes to alleviate pain and accelerate healing. ESWT also causes acute tissue damage. Therefore, its ability to act as an analgesic and cause tissue damage potentially increases the risk of a catastrophic event if used shortly before a strenuous competition such as horseracing. While ESWT is prohibited by many racing jurisdictions within 10 days prior to competition, a test to detect whether a horse has received ESWT is needed. ESWT changes the protein levels of inflammatory mediators in blood, and white blood cells (WBC) typically produce these proteins. Changes in gene expression precede changes in protein production; thus, it was hypothesized that WBC gene transcripts might serve as biomarkers of ESWT. To test this hypothesis, six thoroughbred horses received a single administration of ESWT to the distal limb, and WBC RNA was extracted from blood samples collected before (0 h) and after ESWT (2, 4, 6, 24, 48, and 72 h). Targeted and untargeted analyses evaluated the transcriptome using quantitative PCR (qPCR) and microarray. The expression of IL-1α, IL-1β, TNF-α, IL-1Ra1, IL-1Ra2 and TGF-β1, and BMPR1A in circulating WBCs was significantly up-regulated, while IFN-γ, ZNF483, TMEM80, CAH6, ENPP, and S8723 were significantly down-regulated at various time points following ESWT. These data support the hypothesis that changes in WBC gene transcripts could serve as biomarkers for ESWT.

Achilles tendinopathy: Exploring injury characteristics and current treatment modalities

Achilles tendinopathy is a prevalent overuse injury to the Achilles tendon causing prominent pain and reduction in quality of life. Several biomechanical and anatomical properties govern the pathology of the Achilles tendinopathy, and as a result, choosing the optimal treatment option is challenging. The aim of this review is to study the anatomical and biomechanical characteristics of this injury and explore the available treatment options in order to extrapolate the most suitable option with the best prognosis. Treatment modalities for Achilles tendinopathy vary and include non-operative and operative options. Non-operative treatment modalities include physical therapy, extracorporeal shockwave therapy, injectable agents, and bracing and taping. Operative treatment modalities include surgical procedures, both percutaneous and open. Treatment should be catered to the individual patient. Further research is required in order to confirm the efficacy of the available treatment options, test the viability of novel techniques and approaches, and discover possible new therapeutic modalities.

Effect of extracorporeal shock wave therapy for burn scar regeneration: A prospective, randomized, double-blinded study

PURPOSE

This study aimed to investigate the regeneration effect of extracorporeal shock wave therapy (ESWT) on hypertrophic scar regeneration using objective measurements.

METHODS

This was a double-blinded, randomized, controlled trial of 48 participants who had undergone autologous split-thickness skin grafting (STSG) with same artificial dermis. The ESWT group (n=25) received shock waves with low-energy flux density (0.05-0.30mJ/mm²). The interval between treatments is a 1-week. The ESWT group also received recommended treatment. The control group (n=23) only received standard treatment. We measured skin characteristics before treatment and after 6 weeks for both groups.

RESULTS

No significant intergroup difference was noted at the initial evaluations (p>0.05). The pre- to post-treatment change in the scar thickness (p=0.03) and erythema (p=0.03), greater reduction was found in the ESWT group than control group. The pre- to post-treatment change in the sebum level (p=0.02), more increase was found in the ESWT group. We found no significant differences in the change measurements between the two groups for melanin levels (p=0.62) and transepidermal water loss (TEWL) (p=0.94). The changes (skin distensibility, biological skin elasticity, gross skin elasticity, and skin viscoelasticity) measured with the Cutometer showed no significant differences between the two groups (p=0.87, p=0.32, p=0.37, and p=0.29, respectively).

CONCLUSION

This is the first report of ESWT on hypertrophic scar after burn using objective tools (melanin, erythema, sebum, TEWL, elasticity and thickness). ESWT has objective beneficial effects on burn-associated scar characteristics.

Extracorporeal shock wave promotes activation of anterior cruciate ligament remnant cells and their paracrine regulation of bone marrow stromal cells' proliferation, migration, collagen synthesis, and differentiation

Aims

Proliferation, migration, and differentiation of anterior cruciate ligament (ACL) remnant and surrounding cells are fundamental processes for ACL reconstruction; however, the interaction between ACL remnant and surrounding cells is unclear. We hypothesized that ACL remnant cells preserve the capability to regulate the surrounding cells' activity, collagen gene expression, and tenogenic differentiation. Moreover, extracorporeal shock wave (ESW) would not only promote activity of ACL remnant cells, but also enhance their paracrine regulation of surrounding cells.

Methods

Cell viability, proliferation, migration, and expression levels of Collagen-I (COL-I) A1, transforming growth factor beta (TGF-β), and vascular endothelial growth factor (VEGF) were compared between ACL remnant cells untreated and treated with ESW (0.15 mJ/mm², 1,000 impulses, 4 Hz). To evaluate the subsequent effects on the surrounding cells, bone marrow stromal cells (BMSCs)' viability, proliferation, migration, and levels of Type I Collagen, Type III Collagen, and tenogenic gene (Scx, TNC) expression were investigated using coculture system.

Results

ESW-treated ACL remnant cells presented higher cell viability, proliferation, migration, and increased expression of COL-I A1, TGF-β, and VEGF. BMSC proliferation and migration rate significantly increased after coculture with ACL remnant cells with and without ESW stimulation compared to the BMSCs alone group. Furthermore, ESW significantly enhanced ACL remnant cells' capability to upregulate the collagen gene expression and tenogenic differentiation of BMSCs, without affecting cell viability, TGF-β, and VEGF expression.

Conclusion

ACL remnant cells modulated activity and differentiation of surrounding cells. The results indicated that ESW enhanced ACL remnant cells viability, proliferation, migration, and expression of collagen, TGF-β, VEGF, and paracrine regulation of BMSC proliferation, migration, collagen expression, and tenogenesis.Cite this article: Bone Joint Res 2020;9(8):458-468.

Extracorporeal shock wave therapy mechanisms in musculoskeletal regenerative medicine

Extracorporeal shockwave therapy (ESWT) is a popular non-invasive therapeutic modality in the medical field for the treatment of numerous musculoskeletal disorders. This technique first emerged around the 1980s as extracorporeal shockwave lithotripsy and has been studied since then for its application towards orthopedics and traumatology. ESWT works by the emission of acoustic waves (shockwaves) that carry energy and can propagate through tissues. Shockwaves can generate interstitial and extracellular responses, producing many beneficial effects such as: pain relief, vascularization, protein biosynthesis, cell proliferation, neuro and chondroprotection, and destruction of calcium deposits in musculoskeletal structures. The combination of these effects can lead to tissue regeneration and significant alleviation of pain, improving functional outcomes in injured tissue. Considering these facts, ESWT shows great potential as a useful regenerative medicine technique for the treatment of numerous musculoskeletal injuries.

Extracorporeal Shock Wave Therapy Immediately Affects Achilles Tendon Structure and Widespread Pressure Pain Thresholds in Healthy People: A Repeated-Measures Observational Study

OBJECTIVE

Extracorporeal shockwave therapy is a common clinical treatment for tendinopathy, yet negative effects on tendon structure have been shown in animal studies. This study aimed to investigate the effect of extracorporeal shockwave therapy in healthy participants (i.e., no Achilles tendon pain or pathology).

DESIGN

This study examined the effect of three bouts of weekly extracorporeal shockwave therapy for 3 wks in 13 healthy participants. Outcomes measures assessed were as follows: (a) Achilles tendon structure, quantified using ultrasound tissue characterization (before and 3 hrs after extracorporeal shockwave therapy), (b) pressure pain thresholds, over the Achilles tendon and common extensor tendon origin (before, immediately after, and 3 hrs after extracorporeal shockwave therapy), and (c) hop pain (before and immediately after extracorporeal shockwave therapy).

RESULTS

There was a significant reduction in echo type I (P < 0.05) and increase in echo type II (P < 0.05) at 3 hrs after the first extracorporeal shockwave therapy session that recovered to baseline levels before week 2. There were no significant changes in ultrasound tissue characterization echo pattern observed in subsequent sessions. There were increased pressure pain thresholds immediately after extracorporeal shockwave therapy at the common extensor tendon origin but no significant change at the Achilles tendon. Pressure pain thresholds returned to baseline at 3 hrs after extracorporeal shockwave therapy. There were no significant changes in pressure pain threshold in subsequent sessions.

CONCLUSIONS

Extracorporeal shockwave therapy resulted in transient changes to tendon structure and widespread hyperalgesia.

The Basic Science Behind Low-Intensity Extracorporeal Shockwave Therapy for Erectile Dysfunction: A Systematic Scoping Review of Pre-Clinical Studies

INTRODUCTION

Despite recent promising clinical results, the underlying mechanism of action of low-intensity extracorporeal shockwave therapy (Li-ESWT) for erectile dysfunction (ED) is mostly unclear and currently under investigation.

AIM

To systematically identify and evaluate evidence regarding the basic science behind Li-ESWT for ED, discuss and propose a putative mechanism of action, address the limitations, and imply insights for further investigation in the field.

METHODS

Using Cochrane's methodologic recommendations on scoping studies and systematic reviews, we conducted a systematic scoping review of the literature on experimental research regarding Li-ESWT for ED and other pathologic conditions. The initial systematic search was carried between January and November 2017, with 2 additional searches in April and August 2018. All studies that applied shockwave treatment at an energy flux density >0.25 mJ/mm² were excluded from the final analysis.

MAIN OUTCOME MEASURE

We primarily aimed to clarify the biological responses in erectile tissue after Li-ESWT that could lead to improvement in erectile function.

RESULTS

59 publications were selected for inclusion in this study. 15 experimental research articles were identified on Li-ESWT for ED and 44 on Li-ESWT for other pathologic conditions. Li-ESWT for ED seems to improve erectile function possibly through stimulation of mechanosensors, inducing the activation of neoangiogenesis processes, recruitment and activation of progenitor cells, improving microcirculation, nerve regeneration, remodeling of erectile tissue, and reducing inflammatory and cellular stress responses.

CLINICAL IMPLICATIONS

Improving our understanding of the mechanism of action of Li-ESWT for ED can help us improve our study designs, as well as suggest new avenues of investigation.

STRENGTHS & LIMITATIONS

A common limitation in all these studies is the heterogeneity of the shockwave treatment application and protocol.

CONCLUSION

Li-ESWT for ED, based on current experimental studies, seems to improve erectile function by inducing angiogenesis and reversing pathologic processes in erectile tissue. These studies provide preliminary insights, but no definitive answers, and many questions remain unanswered regarding the mechanism of action, as well as the ideal treatment protocol. Sokolakis I, Dimitriadis F, Teo P, et al. The Basic Science Behind Low-Intensity Extracorporeal Shockwave Therapy for Erectile Dysfunction: A Systematic Scoping Review of Pre-Clinical Studies. J Sex Med 2019;16:168-194.

Sonoelastographic evaluation of plantar fascia after shock wave therapy for recalcitrant plantar fasciitis: A 12-month longitudinal follow-up study

Extracorporeal shockwave therapy (ESWT) is proposed to be effective in reducing pain and improving functional outcome in chronic plantar fasciitis. However, no long-term reports exist on the changes in plantar fascia (PF) elasticity after ESWT. We aimed to evaluate the changes in PF stiffness in patients with plantar fasciitis undergoing ESWT. The visual analogue scale (VAS, 0–100) was used for evaluating heel pain severity. B-mode sonography and strain sonoelastography were used for evaluating the PF thickness and stiffness. The sonoelastogram was analyzed using hue histogram analysis (value: 0–255, from stiffer to softer). All evaluations were recorded before ESWT, and 1 week, 1 month, 3 months, 6 months, and 12 months after ESWT. Repeated measures ANOVA was used to compare pain VAS, PF thickness, and PF hue value at different follow-up time-points. Twenty-two participants (8 men, 14 women) completed all measurements for 12 months. The VAS of heel pain, PF thickness, and PF hue values at pre-ESWT, and 1-week, 1-month, 3-month, 6-month, and 12-month evaluations after ESWT were 62.4 ± 4.2, 49.3 ± 5.8, 38.3 ± 5.7, 27.9 ± 5.3, 18.9 ± 4.7, and 13.2 ± 3.0 (p < 0.01 in all measurements post ESWT versus pre-ESWT); 5.57 ± 0.22 mm, 5.64 ± 0.18 mm, 5.45 ± 0.24 mm, 5.37 ± 0.20 mm, 5.08 ± 0.20 mm, and 4.62 ± 0.15 mm (p < 0.01 at 6-month; otherwise p > 0.05); and 24.5 ± 2.4, 35.2 ± 3.1, 31.0 ± 4.1, 30.5 ± 3.9, 21.4 ± 2.1, and 15.9 ± 1.6 (p < 0.01 at 1-week and 6-month; otherwise p > 0.05), respectively. In conclusion, the heel pain intensity and PF thickness reduced gradually over 12 months after ESWT. The PF stiffness decreased during the first week and increased thereafter; at the 12-month follow-up, stiffness was more than at pre-ESWT.

Thermosensitive Chitosan-Gelatin-Glycerol Phosphate Hydrogels as Collagenase Carrier for Tendon-Bone Healing in a Rabbit Model

Healing of an anterior cruciate ligament graft in bone tunnel yields weaker fibrous scar tissue, which may prolong an already prolonged healing process within the tendon-bone interface. In this study, gelatin molecules were added to thermosensitive chitosan/β-glycerol phosphate disodium salt hydrogels to form chitosan/gelatin/β-glycerol phosphate (C/G/GP) hydrogels, which were applied to 0.1 mg/mL collagenase carrier in the tendon-bone junction. New Zealand white rabbit's long digital extensor tendon was detached and translated into a 2.5-mm diameter tibial plateau tunnel. Thirty-six rabbits underwent bilateral surgery and hydrogel injection treatment with and without collagenase. Histological analyses revealed early healing and more bone formation at the tendon-bone interface after collagenase partial digestion. The area of metachromasia significantly increased in both 4-week and 8-week groups after collagenase treatment (p < 0.01). Micro computed tomography showed a significant increase in total bone volume and bone volume/tissue volume in the 8 weeks after collagenase treatment, compared with the control group. Load-to-failure was significantly higher in the treated group at 8 weeks (23.8 ± 8.13 N vs 14.3 ± 3.9 N; p = 0.008). Treatment with collagenase digestion resulted in a 66% increase in pull-out strength. In conclusion, injection of C/G/GP hydrogel with collagenase improves tendon-to-bone healing in a rabbit model.

Shockwaves Suppress Adipocyte Differentiation via Decrease in PPARγ

Adipogenesis is a crucial cellular process that contributes to the expansion of adipose tissue in obesity. Shockwaves are mechanical stimuli that transmit signals to cause biological responses. The purpose of this study is to evaluate the effects of shockwaves on adipogenesis. We treated 3T3L-1 cells and human primary preadipocytes for differentiation with or without shockwaves. Western blots and quantitative real-time reverse transcriptase PCR (qRT-PCR) for adipocyte markers including peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT-enhancer-binding proteins (C/EBPα) were performed. Extracellular adenosine triphosphate (ATP) and intracellular cyclic adenosine monophosphate (cAMP) levels, which are known to affect adipocyte differentiation, were measured. Shockwave treatment decreased intracellular lipid droplet accumulation in primary human preadipocytes and 3T3-L1 cells after 11–12 days of differentiation. Levels of key adipogenic transcriptional factors PPARγ and/or C/EBPα were lower in shockwave-treated human primary preadipocytes and 3T3L-1 cells after 12–13 days of differentiation than in shockwave-untreated cells. Shockwave treatment induced release of extracellular ATP from preadipocytes and decreased intracellular cAMP levels. Shockwave-treated preadipocytes showed a higher level of β-catenin and less PPARγ expression than shockwave-untreated cells. Supplementation with 8-bromo-cAMP analog after shockwave treatment rescued adipocyte differentiation by preventing the effect of shockwaves on β-catenin, Wnt10b mRNA, and PPARγ expression. Low-energy shockwaves suppressed adipocyte differentiation by decreasing PPARγ. Our study suggests an insight into potential uses of shockwave-treatment for obesity.

Shockwave Therapy Associated With Eccentric Strengthening for Achilles Insertional Tendinopathy: A Prospective Study

Background. The usual initial treatment for insertional Achilles tendinopathy is nonsurgical. Yet there is no standard conservative treatment for Achilles insertional tendinopathy. Shockwave therapy (SWT) has become a reliable option for the management of this illness over the past years. The aim of this study is to report the effectiveness of low-energy SWT associated with an eccentric strengthening protocol in 19 consecutive patients. Methods. This is a prospective study with 19 patients aged between 26 and 72 years diagnosed with insertional Achilles tendinopathy. The protocol consisted of SWT associated with eccentric exercises for 12 weeks. All patients were evaluated on the first day and after 24 weeks (final follow-up) with the Victorian Institute of Sports Assessment-Achilles (VISA-A) score, visual analogue scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) questionnaire, and by algometry. At the last follow-up, patients were also assessed for adherence to the protocol, complications and final outcome (in their perception as success or fail). Results and Conclusion. Fifteen (79%) patients were fully adherent to the Alfredson protocol, and 13 (68%) patients considered the treatment protocol successful. At the last evaluation, patients demanded higher pressure on calcaneus to trigger pain (algometry 1), reported less pain when the algometer was applied with 3 kg (algometry 2), had less global pain (VAS), and had higher AOFAS and VISA-A scores. This study evidences that eccentric loading associated with SWT can dramatically improve patients' symptoms. We can conclude that eccentric loading associated with SWT is an effective treatment for Achilles insertional tendinopathy. Levels of Evidence: Therapeutic, Level III: Prospective cohort.

Revolving doors of tendinopathy: definition, pathogenesis and treatment

The ultimate cure for the tendon pathology continues to elude current science. Despite great steps in technology, the causation and treatment is still not clear. The number of different theories and treatment modalities in the literature may confuse clinicians and patients. In this paper we outline the definitions, evolution of pathogenesis and treatment for tendinopathy. By highlighting these, the aim of this paper is to guide the practitioner in counselling and treating their patients.

Comparative Effectiveness of Different Nonsurgical Treatments for Patellar Tendinopathy: A Systematic Review and Network Meta-analysis

PURPOSE

To investigate the functional improvement and pain reduction of different nonsurgical treatments for patellar tendinopathy (PT), a systematic review with network meta-analysis was performed.

METHODS

Studies were comprehensively searched for without language restrictions in the CENTRAL, MEDLINE, EMBASE, Web of Science, Physiotherapy Evidence Database, and SPORTDiscus databases from inception to May 2018. Randomized controlled trials about nonsurgical treatments for PT were included. The outcome measurements were the Victorian Institute of Sports Assessment (VISA) scale and pain scores (such as the visual analog scale or Numerical Rating Scale). Study quality was evaluated using the Physiotherapy Evidence Database score. Direct comparisons were performed using pairwise meta-analysis, whereas network meta-analysis was performed using a frequentist method in a multivariate random-effects model.

RESULTS

Eleven studies with 430 affected patellar tendons were included in the systematic review. The summary mean difference of improvement in the VISA scale versus the control group for corticosteroid injection was -23.00 (95% confidence interval [CI] -36.73 to -9.27), for leukocyte-rich platelet-rich plasma (LR-PRP) was 13.22 (95% CI 2.37-24.07), for focused extracorporeal shockwave therapy (ESWT) was -1.28 (95% CI -6.25 to 3.68), for radial ESWT was -6.68 (95% CI -20.20 to 6.84), for ultrasound was -0.70 (95% CI -11.23 to 9.83), for autologous blood injection was -0.60 (95% CI -9.30 to 8.10), for dry needling was 17.51 (95% CI -2.57 to 37.60), for topical glyceryl trinitrate was -0.90 (95% CI -13.07 to 11.27), and for skin-derived tendon-like cells was 10.40 (95% CI -1.59 to 22.39). LR-PRP (Surface Under the Cumulative Ranking curve [SUCRA] = 87.5%) or dry needling (SUCRA = 90.5%) was most likely to be ranked the best in terms of improvement on the VISA scale. Compared with the control group, the summary mean difference of the change in pain score for corticosteroid injection was 0.80 (95% CI -3.48 to 5.08), for LR-PRP was -1.87 (95% CI -3.28 to -0.46), for focused ESWT was 0.13 (95% CI -0.68 to 0.93), for radial ESWT was 0.03 (95% CI -1.92 to 1.98), for ultrasound was -0.20 (95% CI -1.49 to 1.09), for autologous blood injection was 0.60 (95% CI -0.73 to 1.93), for dry needling was -0.37 (95% CI -2.71 to 1.97), and for topical glyceryl trinitrate was -0.50 (95% CI -2.55 to 1.55). The treatment most likely to be ranked the best in terms of change in pain score was LR-PRP (SUCRA = 94.9%).

CONCLUSIONS

The network meta-analysis demonstrated that LR-PRP has the greatest functional improvement and pain reduction for PT compared with other treatment options. However, the treatment effect estimates can be biased by the possible intransitivity and should not be overestimated.

LEVEL OF EVIDENCE

Level I, meta-analysis of Level I studies.

Aspirin promotes tenogenic differentiation of tendon stem cells and facilitates tendinopathy healing through regulating the GDF7/Smad1/5 signaling pathway

Tendinopathy is a common musculoskeletal system disorder in sports medicine, but regeneration ability of injury tendon is limited. Tendon stem cells (TSCs) have shown the definitive treatment evidence for tendinopathy and tendon injuries due to their tenogenesis capacity. Aspirin, as the representative of nonsteroidal anti-inflammatory drugs for its anti-inflammatory and analgestic actions, has been commonly used in treating tendinopathy in clinical, but the effect of aspirin on tenogenesis of TSCs is unclear. We hypothesized that aspirin could promote injury tendon healing through inducing TSCs tenogenesis. The aim of the present study is to make clear the effect of aspirin on TSC tenogenesis and tendon healing in tendinopathy, and thus provide new treatment evidence and strategy of aspirin for clinical practice. First, TSCs were treated with aspirin under tenogenic medium for 3, 7, and 14 days. Sirius Red staining was performed to observe the TSC differentiation. Furthermore, RNA sequencing was utilized to screen out different genes between the induction group and aspirin treatment group. Then, we identified the filtrated molecules and compared their effect on tenogenesis and related signaling pathway. At last, we constructed the tendinopathy model and compared biomechanical changes after aspirin intake. From the results, we found that aspirin promoted tenogenesis of TSCs. RNA sequencing showed that growth differentiation factor 6 (GDF6), GDF7, and GDF11 were upregulated in induction medium with the aspirin group compared with the induction medium group. GDF7 increased tenogenesis and activated Smad1/5 signaling. In addition, aspirin increased the expression of TNC, TNMD, and Scx and biomechanical properties of the injured tendon. In conclusion, aspirin promoted TSC tenogenesis and tendinopathy healing through GDF7/Smad1/5 signaling, and this provided new treatment evidence of aspirin for tendinopathy and tendon injuries.

Aspirin inhibits adipogenesis of tendon stem cells and lipids accumulation in rat injury tendon through regulating PTEN/PI3K/AKT signalling

Tendon injury repairs are big challenges in sports medicine, and fatty infiltration after tendon injury is very common and hampers tendon injury healing process. Tendon stem cells (TSCs), as precursors of tendon cells, have shown promising effect on injury tendon repair for their tenogenesis and tendon extracellular matrix formation. Adipocytes and lipids accumulation is a landmark event in pathological process of tendon injury, and this may induce tendon rupture in clinical practice. Based on this, it is important to inhibit TSCs adipogenesis and lipids infiltration to restore structure and function of injury tendon. Aspirin, as the representative of non‐steroidal anti‐inflammatory drugs (NSAIDs), has been widely used in tendon injury for its anti‐inflammatory and analgesic actions, but effect of aspirin on TSCs adipogenesis and fatty infiltration is still unclear. Under adipogenesis conditions, TSCs were treated with concentration gradient of aspirin. Oil red O staining was performed to observe changes of lipids accumulation. Next, we used RNA sequencing to compare profile changes of gene expression between induction group and aspirin‐treated group. Then, we verified the effect of filtrated signalling on TSCs adipogenesis. At last, we established rat tendon injury model and compared changes of biomechanical properties after aspirin treatment. The results showed that aspirin decreased lipids accumulation in injury tendon and inhibited TSCs adipogenesis. RNA sequencing filtrated PTEN/PI3K/AKT signalling as our target. After adding the signalling activators of VO‐Ohpic and IGF‐1, inhibited adipogenesis of TSCs was reversed. Still, aspirin promoted maximum loading, ultimate stress and breaking elongation of injury tendon. In conclusion, by down‐regulating PTEN/PI3K/AKT signalling, aspirin inhibited adipogenesis of TSCs and fatty infiltration in injury tendon, promoted biomechanical properties and decreased rupture risk of injury tendon. All these provided new therapeutic potential and medicine evidence of aspirin in treating tendon injury and tendinopathy.

Extracorporeal shock wave therapy role in the treatment of burn patients. A systematic literature review

INTRODUCTION

Extracorporeal shock wave therapy (ESWT), first described in the eighties for the treatment of urolithiasis, has also been applied in other fields such as orthopaedics and chronic wound care. Recently it has also been used in the treatment of burns and its sequelae since several studies suggest it could be an important tool in the conservative management of these conditions. The aim of this article is to review the literature for published evidence on the use of ESWT for the treatment of acute burn patients and its sequelae and to elaborate a brief report on the current state of the matter.

MATERIAL AND METHODS

We carried on a search on PUBMED database and Cochrane database with the following terms: ('burns' [title/abstract] OR 'burn' [title/abstract]) AND "shock wave" ([title/abstract]). For an optimal reporting of the studies found we followed the PRISMA statement.

RESULTS

This search found 34 articles from which only 15 were actually related to the use of ESWT in burn patients. From these 15 articles, 7 involved the use of ESWT in the treatment of acute burns, 6 related to its application in post-burn scars, 1 in the treatment of heterotopic ossification and 1 was about the use of ESWT in skin-graft donor site. Except for the latter, all of them were carefully reviewed.

CONCLUSION

Scientific evidence on the use of ESWT for the treatment of burn patients is weak due to the paucity of studies and their low quality. However, ESWT seems to be a promising tool in this field and therefore more high-quality trials should be conducted.

Use of Human Placenta-Derived Cells in a Preclinical Model of Tendon Injury

BACKGROUND

Emerging data suggest that human cells derived from extraembryonic tissues may have favorable musculoskeletal repair properties. The purpose of this study was to determine whether the injection of human placenta-derived mesenchymal-like stromal cells, termed placental expanded cells (PLX-PAD), would improve tendon healing in a preclinical model of tendinopathy.

METHODS

Sixty male Sprague-Dawley rats underwent bilateral patellar tendon injection with either saline solution (control) or PLX-PAD cells (2 × 10 cells/100 µL) 6 days after collagenase injection to induce tendon degeneration. Animals were killed at specific time points for biomechanical, histological, and gene expression analyses of the healing patellar tendons.

RESULTS

Biomechanical testing 2 weeks after the collagenase injury demonstrated better biomechanical properties in the tendons treated with PLX-PAD cells. The load to failure of the PLX-PAD-treated tendons was higher than that of the saline-solution-treated controls at 2 weeks (77.01 ± 10.51 versus 58.87 ± 11.97 N, p = 0.01). There was no significant difference between the 2 groups at 4 weeks. There were no differences in stiffness at either time point. Semiquantitative histological analysis demonstrated no significant differences in collagen organization or cellularity between the PLX-PAD and saline-solution-treated tendons. Gene expression analysis demonstrated higher levels of interleukin-1β (IL-1β) and IL-6 early in the healing process in the PLX-PAD-treated tendons.

CONCLUSIONS

Human placenta-derived cell therapy induced an early inflammatory response and a transient beneficial effect on tendon failure load in a model of collagenase-induced tendon degeneration.

CLINICAL RELEVANCE

Human extraembryonic tissues, such as the placenta, are an emerging source of cells for musculoskeletal repair and may hold promise as a point-of-care cell therapy for tendon injuries.

Thermal pretreatment promotes the protective effect of HSP70 against tendon adhesion in tendon healing by increasing HSP70 expression

Tendon adhesion is a substantial challenge for tendon repair. Thermal pretreatment (TP) may decrease inflammation by upregulating heat shock proteins (HSPs). The present study intends to identify the function that TP serves when combined with HSP70 overexpression in tendon healing and adhesion in rats. Sprague‑Dawley male rats were used to establish a surgically ablative tendon postoperative suture model, and the positive expression of the HSP70 protein was measured using immunohistochemistry. Changes to the blood vessels and collagenous fiber, in addition to the maximum tensile strength and the tendon sliding distance, were detected under a microscope. Finally, HSP70, tumor growth factor β (TGF‑β), and insulin‑like growth factor 1 (IGF‑1) mRNA and protein levels were all determined by employing reverse transcription‑quantitative polymerase chain reaction and western blot analysis methods. The positive expression of the HSP70 protein increased following TP. Furthermore, TP reduced the infiltration of inflammatory cells and improved the collagenous arrangement, accompanied by an increased maximum tensile force and tendon gliding distance following surgery. In addition, TP increased the mRNA and protein expression levels of HSP70, TGF‑β and IGF‑1. Altogether, TP increases HSP70 expression, thereby reducing postoperative traumatic inflammation and establishing tendon adhesion and promoting tendon healing. Thus, TP may be a potential strategy for the treatment of tendon adhesion.