Mechanical Stimulation (Pulsed Electromagnetic Fields "PEMF" and Extracorporeal Shock Wave Therapy "ESWT") and Tendon Regeneration: A Possible Alternative

Experimental study of radial extracorporeal shock wave therapy for periprosthetic osteolysis induced by wear particles

Radial Extracorporeal Shock Wave Therapy (rESWT) is applied as a conservative treatment modality in orthopedics, yet its effectiveness in addressing aseptic loosening of cementless joint prostheses remains unclear. Through animal experimentation, we have revealed that in a titanium particle-induced osteolysis rat model, rESWT intervention significantly increased periprosthetic bone density compared to untreated controls, concurrently reducing osteolytic lesion area and lowering serum IL-1β levels. Histological analyses demonstrated a relative decrease in osteoclast counts within the treatment group versus non-treated controls. These findings indicate that rESWT, through mechanisms involving anti-inflammatory actions and suppression of osteoclastogenesis, may serve as a non-invasive therapeutic strategy for preventing and managing periprosthetic bone loss, demonstrating clinical potential to delay or eliminate the necessity for revision surgeries.

Extracorporeal Shockwave Therapy for Greater Trochanteric Pain Syndrome: A Systematic Review with Meta-Analysis of Randomized Clinical Trials

BACKGROUND

Greater trochanteric pain syndrome (GTPS) affects 17.6% of adults aged 50 to 79 years, particularly women. While exercise therapy and corticosteroid injections (CSIs) are common treatments, their limitations include inadequate pain control and potential tendon weakening. Extracorporeal shockwave therapy (ESWT) is an emerging alternative for GTPS. This systematic review assessed ESWT's efficacy in GTPS by evaluating pain and functional outcomes at different follow-up intervals.

METHODS

A literature search of PubMed, Embase, and Web of Science for randomized clinical trials (RCTs) was conducted comparing ESWT with other GTPS treatments up to March 1, 2024. Two reviewers independently extracted data, assessing study quality using the Cochrane risk-of-bias tool. A random-effects pairwise meta-analysis compared ESWT with other treatments.

RESULTS

Eight RCTs involving 754 patients (169 male, 585 female patients) were included. Seven RCTs were deemed high risk of bias, and 1 RCT had some concerns. Five RCTs investigated focused on focused ESWT, and 3 examined radial ESWT. ESWT provided significantly lower pain scores than other treatments at 2 to 4 months (standardized mean difference = -0.431; 95% confidence interval [CI], -0.82 to -0.039; I2 = 83%). Functional improvement (Lower Extremity Functional Scale) was significantly higher at 6 months (weighted mean difference = 6.68; 95% CI, 3.11-10.25; I2 = 0%) but did not exceed the minimal clinically important difference. Focused ESWT provided greater pain reduction than radial ESWT.

CONCLUSION

Three weekly ESWT sessions offer short-term pain relief at 2 to 4 months for patients with GTPS, especially with focused ESWT. Functional improvements at 6 months were notable but not clinically significant. These findings suggest ESWT may complement or serve as an alternative to CSIs and exercise. However, caution is needed when interpreting these results due to high risk of bias with the included RCTs and heterogeneity across the studies. Further high-quality trials are needed to confirm ESWT's long-term benefits over other treatments.

LEVEL OF EVIDENCE

Level II. See Instructions for Authors for a complete description of levels of evidence.

Efficacy of Extracorporeal Shock Wave and Pulse Electromagnetic Field Therapies in Calcaneal Spurs

BACKGROUND

Various treatment methods are available for calcaneal spur, which can cause disability. Objective: To evaluate the efficacy of pulsed electromagnetic field therapy (PEMFT) added to extracorporeal shock wave therapy (ESWT) on pain and functional capacity in treating calcaneal spurs.

METHODS

Patients with calcaneal spurs who were recommended ESWT or ESWT+PEMFT and whose Foot Function Index (FFI) and visual analogue scale (VAS) values were available in their records were retrospectively analyzed. The two groups were ESWT (n=35) and ESWT+PEMFT (n=40). FFI and VAS scores were obtained from their records before treatment, after treatment, and in the third month after treatment.

RESULTS

The two groups were similar regarding their pre-treatment FFI and VAS scores. In intra-group evaluation, statistically significant decreases were found in terms of the FFI pain, disability, and activity limitation and VAS scores in both groups after treatment and in the third month after treatment compared to the pre-treatment period. In the comparison between the groups, the post-treatment and post-treatment third-month FFI pain, disability, and activity limitation and VAS scores were significantly lower in the PEMFT+ESWT group than the ESWT group (P<0.001).

CONCLUSION

A calcaneal spur is a condition that can cause pain and functional limitation in patients. Various studies have demonstrated the efficacy of ESWT in the treatment of calcaneal spurs. In our study, we observed that PEMFT added to ESWT significantly improved the pain and functionality of the patients. Further studies are needed to evaluate the efficacy of PEMFT in calcaneal spurs.

Gluteal Tendinopathy: Critical Analysis Review of Current Nonoperative Treatments

» Gluteal tendinopathy/greater trochanteric pain syndrome (GTPS) is the most prevalent of all lower limb tendinopathies, affecting 1 in 4 women older than 50 years and commonly individuals within their fifth and sixth decades of life regardless of activity level.» The condition is believed to originate from age-related degenerative changes about the hip abductor tendon insertions and the surrounding bursae, and is exacerbated by congenital and acquired abnormal hip biomechanics.» Treatment of gluteal tendinopathy/GTPS often begins with noninvasive nonoperative modalities such as activity modifications, nonsteroidal anti-inflammatory drugs, and physical therapy. For recalcitrant symptoms, additional nonoperative therapies have been used; however, there remains a lack of comparative efficacy between these adjunct treatments.» In this article, we examine the available literature regarding the nonoperative management of gluteal tendinopathy/GTPS and provide insight into the effectiveness of current treatment modalities.

Pro-inflammatory activity of long noncoding RNA FOXD2-AS1 in Achilles tendinopathy

Achilles tendinopathy is a prevalent clinical problem that plagues athletes and general populations. Achilles tendon healing is a complex process, and so far, there is no successful long-term solution to Achilles tendinopathy in the field of microsurgery due to its poor natural regeneration ability. Limitations in understanding the pathogenesis of Achilles tendon development and Achilles tendon injury hinder clinical treatment developments. There is an increasing demand for innovative conservative treatments that can improve Achilles tendon injury. In this study, a Sprague-Dawley rat model of Achilles tendinopathy was established. Lentiviral vectors that interfere with the expression of FOXD2-AS1, miR-21-3p, or PTEN were injected every 3 days. Rats were euthanized after 3 weeks, and the effect of FOXD2-AS1, miR-21-3p, or PTEN on Achilles tendon healing was analyzed by histological observation, biomechanical test, and examinations of inflammatory factors and tendon markers. As measured, downregulating FOXD2-AS1 or upregulating miR-21-3p improved histological structure, suppressed inflammation, promoted the expression of tendon markers, and optimized the biomechanical properties of Achilles tendon. Upregulating PTEN was capable of reversing the promoting effect of inhibition of FOXD2-AS1 on Achilles tendon healing. As concluded, deficiency of FOXD2-AS1 accelerates the healing of Achilles tendon injury and improves tendon degeneration by regulating the miR-21-3p/PTEN axis and promoting the activation of the PI3K/AKT signaling pathway.

Global trends in research on extracorporeal shock wave therapy (ESWT) from 2000 to 2021

BACKGROUND

This study intended to analyze the application of extracorporeal shock wave therapy in medicine and to evaluate the quality of related literature.

METHODS

All publications were extracted from 2000 to 2021 from the Web of Science Core Collection (WoSCC). The literature characteristics were depicted by VOSviewer (version 1.6.15) and the online bibliometric website ( http://bibliometric.com/ ). The future trends and hotspots were conducted by Bibliographic Item Co-occurrence Matrix Builder (version 2.0) and gCLUTO software.

RESULTS

We analyzed 1774 articles corresponding to the criteria for ESWT publications from 2000 to 2021. Most studies were conducted within the United States and China which besides have the most cooperation. The most published research institutions are Chang Gung University, Kaohsiung Chang Gung Memorial Hospital, and Kaohsiung Medical University. Six research hotspots were identified by keyword clustering analysis: Cluster0: The effects of ESWT on muscle spasticity; Cluster1: The application of ESWT in osteoarthritis (OA); Cluster2: Therapeutic effect of ESWT on tendon diseases; Cluster3: Early application of ESWT/ESWL in urolithiasis; Cluster4: The Role of angiogenesis in ESWT and the efficiency of ESWT for penile disease; Cluster5: The Special value of radial extracorporeal shock wave therapy (rESWT).

CONCLUSIONS

A comprehensive and systematic bibliometric analysis of ESWT was conducted in our study. We identified six ESWT-related research hotspots and predicted future research trends. With the gradual increase of research on ESWT, we find that ESWT is used more and more extensively, such in musculoskeletal disease, bone delay union, neurological injury, andrology disorders, lymphedema, and so on. In addition, the mechanism is not destructive damage, as initially thought, but a restorative treatment. Furthermore, delayed union, cellulite, burn, and diabetic foot ulcers may be the future direction of scientific study.

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.

The Role of PEMFs on Bone Healing: An In Vitro Study

Bone responses to pulsed electromagnetic fields (PEMFs) have been extensively studied by using devices that expose bone cells to PEMFs to stimulate extracellular matrix (ECM) synthesis for bone and cartilage repair. The aim of this work was to highlight in which bone healing phase PEMFs exert their action. Specifically, we evaluated the effects of PEMFs both on human adipose mesenchymal stem cells (hASCs) and on primary human osteoblasts (hOBs) by testing gene and protein expression of early bone markers (on hASCs) and the synthesis of late bone-specific proteins (on hOBs) as markers of bone remodeling. Our results indicate that PEMFs seem to exert their action on bone formation, acting on osteogenic precursors (hASCs) and inducing the commitment towards the differentiation pathways, unlike mature and terminally differentiated cells (hOBs), which are known to resist homeostasis perturbation more and seem to be much less responsive than mesenchymal stem cells. Understanding the role of PEMFs on bone regenerative processes provides important details for their clinical application.

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.

Safety and efficacy of treating post-burn pathological scars with extracorporeal shock wave therapy: A meta-analysis of randomised controlled trials

The clinical application of shockwave therapy has expanded to the treatment of pathological scars. The objective of this systematic review and meta-analysis is to quantitatively evaluate the efficacy and safety of extracorporeal shockwave therapy combined with comprehensive rehabilitation therapy on post-burn pathological scars compared to comprehensive rehabilitation therapy alone. The randomised controlled trials of extracorporeal shockwave therapy for post-burn pathological scars published in English and Chinese languages before October 2021 were included. The methodological quality and risk of bias of the selected articles were assessed with the Cochrane Collaboration's 'risk of bias' tool. RevMan software was applied for data analysis. This is the first systematic review and meta-analysis considering the effectiveness and safety of extracorporeal shockwave therapy on post-burn pathological scars. And nine randomised controlled trials involving 422 patients were included in this meta-analysis. The meta-analysis results showed that, compared with comprehensive rehabilitation therapy alone, extracorporeal shockwave therapy combined with comprehensive rehabilitation therapy was more effective in relieving pain (standardized mean difference [SMD] = -0.59, 95% confidence interval [CI]: [-0.87 to -0.31], p < 0.0001) and pruritus related to pathological scars (SMD = -0.94; 95% CI: [-1.25 to -0.63], p = 0.004), improving scars' appearance (SMD = -1.78, 95% CI: [-3.37 to -0.19], p = 0.03) and elasticity (SMD = 0.25, 95% CI: [0.29-0.21], p < 0.00001), decreasing scars thickness (SMD = -0.13, 95% CI: [-0.25 to -0.01], p = 0.04) and promoting the maturation status of scars (SMD = -2.86, 95% CI: [-3.96 to -1.76], p < 0.00001). There were no reported serious adverse events during and after extracorporeal shockwave therapy in the included studies. Available data preliminarily suggested that the combination of extracorporeal shockwave therapy and comprehensive rehabilitation therapy had better therapeutic effect on post-burn pathological scars than comprehensive rehabilitation therapy alone, without obvious side effects. However, further clinical well-controlled randomised controlled trials are needed. Systematic review registration ID: PROSPERO CRD42022297573.

Effectiveness of Focused Shockwave Therapy versus Radial Shockwave Therapy for Noncalcific Rotator Cuff Tendinopathies: A Randomized Clinical Trial

Background

The superiority of focused shockwave therapy (F-SWT) versus radial shockwave therapy (R-SWT) for treating noncalcific rotator cuff tendinopathies remains controversial. This study is aimed at comparing the effectiveness of F-SWT versus R-SWT for the management of noncalcific rotator cuff tendinopathies.

Methods

A total of 46 patients affected by noncalcific rotator cuff tendinopathies were randomly divided into 2 groups of 23 individuals. Patients in group A received 4 sessions of F-SWT, while patients in group B were treated by 4 sessions of R-SWT. In each session, mean energy flux density (EFD) for F-SW 3000 shots was 0.09 ± 0.018 mJ/mm² with 5.1 ± 0.5 Hz, while average pressure for R-SW 3000 shots was 4.0 ± 0.35 bar with 3.2 ± 0.0 Hz. Pain level and shoulder function were assessed with the numerical rating scale (NRS) and Constant-Murley Scale (CMS). The primary endpoint was the change in the mean NRS pain score from baseline to 24 weeks after the intervention. Secondary endpoints were changes in the mean NRS pain scores at all other follow-up points, changes in the mean CMS scores, and radiographic findings.

Results

There were no significant differences between the two groups regarding NRS pain score and CMS score within 24 weeks after intervention (all p > 0.05). However, F-SWT resulted in significantly lower NRS compared with R-SWT at 24 weeks and 48 weeks after treatment (2.7 ± 1.0 vs. 4.5 ± 1.2 and 1.4 ± 1.0 vs. 3.0 ± 0.8, respectively, all p < 0.001). Similar results were found in CMS changes and radiographic findings.

Conclusions

Both F-SWT and R-SWT are effective in patients with noncalcific rotator cuff tendinopathy. F-SWT proved to be significantly superior to R-SWT at long-term follow-up (more than 24 weeks). This trial is registered with ChiCTR1900022932.

Pulsed electromagnetic fields improve the healing process of Achilles tendinopathy: a pilot study in a rat model

Aims

In the context of tendon degenerative disorders, the need for innovative conservative treatments that can improve the intrinsic healing potential of tendon tissue is progressively increasing. In this study, the role of pulsed electromagnetic fields (PEMFs) in improving the tendon healing process was evaluated in a rat model of collagenase-induced Achilles tendinopathy.

Methods

A total of 68 Sprague Dawley rats received a single injection of type I collagenase in Achilles tendons to induce the tendinopathy and then were daily exposed to PEMFs (1.5 mT and 75 Hz) for up to 14 days - starting 1, 7, or 15 days after the injection - to identify the best treatment option with respect to the phase of the disease. Then, 7 and 14 days of PEMF exposure were compared to identify the most effective protocol.

Results

The daily exposure to PEMFs generally provided an improvement in the fibre organization, a decrease in cell density, vascularity, and fat deposition, and a restoration of the physiological cell morphology compared to untreated tendons. These improvements were more evident when the tendons were exposed to PEMFs during the mid-acute phase of the pathology (7 days after induction) rather than during the early (1 day after induction) or the late acute phase (15 days after induction). Moreover, the exposure to PEMFs for 14 days during the mid-acute phase was more effective than for 7 days.

Conclusion

PEMFs exerted a positive role in the tendon healing process, thus representing a promising conservative treatment for tendinopathy, although further investigations regarding the clinical evaluation are needed.

Cite this article: Bone Joint Res 2020;9(9):613–622.

Promising application of Pulsed Electromagnetic Fields (PEMFs) in musculoskeletal disorders

Increasing evidence suggests that an exogenous electromagnetic field might be involved in many biologic processes which are of great importance for therapeutic interventions. Pulsed electromagnetic fields (PEMFs) are known to be a noninvasive, safe and effective therapy agent without apparent side effects. Numerous studies have shown that PEMFs possess the potential to become a stand-alone or adjunctive treatment modality for treating musculoskeletal disorders. However, several issues remain unresolved. Prior to their widely clinical application, further researches from well-designed, high-quality studies are still required to standardize the treatment parameters and derive the optimal protocol for health-care decision making. In this review, we aim to provide current evidence on the mechanism of action, clinical applications, and controversies of PEMFs in musculoskeletal disorders.

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.

Therapeutic Efficacy of Intratendinous Delivery of Dexamethasone Using Porous Microspheres for Amelioration of Inflammation and Tendon Degeneration on Achilles Tendinitis in Rats

Achilles tendinitis caused by overuse, aging, or gradual wear induces pain, swelling, and stiffness of Achilles tendon and leads to tendon rupture. This study was performed to investigate the suppression of inflammation responses in interleukin-1β- (IL-1β-) stimulated tenocytes in vitro and the suppression of the progression of Achilles tendinitis-induced rat models in vivo using dexamethasone-containing porous microspheres (DEX/PMSs) for a sustained intratendinous DEX delivery. DEX from DEX/PMSs showed the sustained release of DEX. Treatment of IL-1β-stimulated tenocytes with DEX/PMSs suppressed the mRNA levels for COX-2, IL-1β, IL-6, and TNF-α. The intratendinous injection of DEX/PMSs into Achilles tendinitis rats both decreased the mRNA levels for these cytokines and increased mRNA levels for anti-inflammatory cytokines IL-4 and IL-10 in tendon tissues. Furthermore, DEX/PMSs effectively prevented tendon degeneration by enhancing the collagen content and biomechanical properties. Our findings suggest that DEX/PMSs show great potential as a sustained intratendinous delivery system for ameliorating inflammation responses as well as tendon degeneration in Achilles tendinitis.

Changes on Tendon Stiffness and Clinical Outcomes in Athletes Are Associated With Patellar Tendinopathy After Eccentric Exercise

OBJECTIVE

Eccentric exercise is commonly used as a form of loading exercise for individuals with patellar tendinopathy. This study investigated the change of mechanical properties and clinical outcomes and their interrelationships after a 12-week single-legged decline-board exercise with and without extracorporeal shockwave therapy (ESWT).

DESIGN

Randomized controlled trial.

SETTING

Outpatient clinic of a university.

PARTICIPANTS

Thirty-four male in-season athletes with patellar tendinopathy for more than 3 months were randomized into exercise and combined groups.

INTERVENTIONS

The exercise group received a 12-week single-legged decline-squat exercise, and the combined group performed an identical exercise program in addition to a weekly session of ESWT in the initial 6 weeks.

MAIN OUTCOME MEASURES

Tendon stiffness and strain were examined using ultrasonography and dynamometry. Visual analog scale and Victoria Institute of Sports Assessment-patella (VISA-p) score were used to assess pain and dysfunction. These parameters were measured at preintervention and postintervention.

RESULTS

Significant time effect but no significant group effect on the outcome measures; significant reduction in tendon stiffness (P = 0.02) and increase in tendon strain (P = 0.00); and reduction of intensity of pain (P = 0.00) and dysfunction (P = 0.00) were observed. Significant correlations between changes in tendon stiffness and VISA-p score (ρ = -0.58, P = 0.05); alteration in tendon strain, pain intensity (ρ = -0.63, P = 0.03); and VISA-p score (ρ = 0.60, P = 0.04) were detected after the exercise program.

CONCLUSIONS

Eccentric exercise-induced modulation on tendon mechanical properties and clinical symptoms are associated in athletes with patellar tendinopathy.

Effects of the extracorporeal shock wave therapy on the skin: an experimental study

Extracorporeal shock wave therapy (ESWT) has been extensively studied for its multiple biological properties, and although it is widely applied in esthetical procedures, little is known about its effects on the epidermis and dermis. In this study, a histological and immunohistochemical study of the effects of ESWT was performed on rat skin. Forty-five female rats were treated with one or two sessions of ESWT and sacrificed on days 1, 7, 14, and 21 after treatment. The samples were histologically processed and then morphometric analyses were performed to assess the epidermis, dermis, and subcutaneous fat tissue thickness. Immunohistochemical reactions were also performed against the antibodies: basic fibroblastic growth factor (FGF2), its receptor (FGFR1), and α-smooth muscle actin. Slides were scanned and digitally assessed, to determine the microvessel density (MVD) and digital scoring of the immunohistochemical staining. The results showed that ESWT produced a significantly higher collagen content, MVD, and epidermis and dermis thickness than the control, non-treated group. Both in epidermis and dermis, FGF2 was overexpressed in the ESWT-treated groups, whereas FGFR1 was increased only in the group treated with two ESWT sessions at 21-days post-treatment. The ESWT-treated groups have also shown diminished thickness of subcutaneous fat tissue. In conclusion, ESWT induces neocollagenesis and neoangiogenesis, and upregulates the FGF2 expression, particularly in the groups treated with two sessions. Furthermore, it was demonstrated that overexpression of FGF2 on skins treated with ESWT seems to be a key role on its mechanism of action.

Pulsed Electromagnetic Fields Improve Tenogenic Commitment of Umbilical Cord-Derived Mesenchymal Stem Cells: A Potential Strategy for Tendon Repair-An In Vitro Study

Tendon repair is a challenging procedure in orthopaedics. The use of mesenchymal stem cells (MSCs) and pulsed electromagnetic fields (PEMF) in tendon regeneration is still investigational. In this perspective, MSCs isolated from the human umbilical cord (UC) may represent a possible candidate for tendon tissue engineering. The aim of the study is to evaluate the effect of low-frequency PEMF on tenogenic differentiation of MSCs isolated from the human umbilical cord (UC-MSCs) in vitro. 15 fresh UC samples from women with healthy pregnancies were retrieved at the end of caesarean deliveries. UC samples were manually minced into small fragments (less than 4 mm length) and cultured in MSC expansion medium. Part of the UC-MSCs was subsequently cultured with PEMF and tenogenic growth factors. UC-MSCs were subjected to pulsed electromagnetic fields for 2 h/day, 4 h/day, or 8 h/day. UC-MSCs cultured with FGF-2 and stimulated with PEMF showed a greater production of collagen type I and scleraxis. The prolonged exposure to PEMF was also related to the greatest expression of tenogenic markers. Thus, the exposure to PEMF provides a positive preconditioning biophysical stimulus, which may enhance UC-MSC tenogenic potential.

Efficacy and safety of extracorporeal shock wave therapy for acute and chronic soft tissue wounds: A systematic review and meta-analysis

This study aimed to evaluate and compare the effects of extracorporeal shock wave therapy (ESWT) and conventional wound therapy (CWT) for acute and chronic soft tissue wounds. All English-language articles on ESWT for acute and chronic soft tissue wounds indexed in PubMed, Medline, Embase, Cochrane Central Register of Controlled Trials, Cochrane Library, Physiotherapy Evidence Database, and HealthSTAR published prior to June 2017 were included, as well as corresponding articles cited in reference lists of related review articles. The methodological quality of the selected studies was assessed with the Cochrane Collaboration's "risk of bias" tool. Study design, subject demographics, wound aetiology, treatment protocols, assessment indexes, and follow-up duration were extracted. The fixed or random-effects model was used to calculate the pooled effect sizes according to studies' heterogeneity. Ten randomised controlled trials (RCTs) involving 473 patients were included in this systematic review and meta-analysis. The meta-analysis showed that ESWT statistically significantly increased the healing rate of acute and chronic soft tissue wounds 2.73-fold (odds ratio, OR = 3.73, 95% confidence interval, CI: 2.30-6.04, P < .001) and improved wound-healing area percentage by 30.45% (Standardized Mean Difference (SMD) = 30.45; 95% CI: 23.79-37.12; P < .001). ESWT reduced wound-healing time by 3 days (SMD = -2.86, 95% CI:-3.78 to -1.95, P < .001) for acute soft tissue wounds and 19 days (SMD = -19.11, 95% CI: -23.74 to -14.47, P < .001) for chronic soft tissue wounds and the risk of wound infection by 53% (OR = 0.47, 95% CI: 0.24-0.92, P = .03) when compared with CWT alone. Serious adverse effects were not reported. ESWT showed better therapeutic effects on acute and chronic soft tissue wounds compared with CWT alone. However, higher-quality and well-controlled RCTs are needed to further assess the role of ESWT for acute and chronic soft tissue wounds.

Exploring the In Vivo Anti-Inflammatory Actions of Simvastatin-Loaded Porous Microspheres on Inflamed Tenocytes in a Collagenase-Induced Animal Model of Achilles Tendinitis

Tendon rupture induces an inflammatory response characterized by release of pro-inflammatory cytokines and impaired tendon performance. This study sought to investigate the therapeutic effects of simvastatin-loaded porous microspheres (SIM/PMSs) on inflamed tenocytes in vitro and collagenase-induced Achilles tendinitis in vivo. The treatment of SIM/PMSs in lipopolysaccharide (LPS)-treated tenocytes reduced the mRNA expressions of pro-inflammatory cytokines (Matrix metalloproteinase-3 (MMP-3), cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α)). In addition, the local injection of SIM/PMSs into the tendons of collagenase-induced Achilles tendinitis rat models suppressed pro-inflammatory cytokines (MMP-3, COX-2, IL-6, TNF-α, and MMP-13). This local treatment also upregulated anti-inflammatory cytokines (IL-4, IL-10, and IL-13). Furthermore, treatment with SIM/PMSs also improved the alignment of collagen fibrils and effectively prevented collagen disruption in a dose-dependent manner. Therefore, SIM/PMSs treatment resulted in an incremental increase in the collagen content, stiffness, and tensile strength in tendons. This study suggests that SIM/PMSs have great potential for tendon healing and restoration in Achilles tendinitis.

Short-term effects of extracorporeal shock wave therapy on bone mineral density in postmenopausal osteoporotic patients

It has been proved that extracorporeal shock wave therapy (ESWT) could promote new bone formation. Therefore, we designed an experiment to test the efficiency of ESWT on BMD in postmenopausal osteoporotic patients. The results showed that ESWT could effectively improve the local bone mass of the treated bone area within a short duration.

INTRODUCTION

This study evaluated the short-term effectiveness of extracorporeal shock wave therapy (ESWT) on bone mineral density (BMD).

METHODS

A total of 64 postmenopausal osteoporotic patients were recruited and randomized into 3 groups in 2015. Groups A (n = 20) and B (n = 21) patients received a single-session of low- or high-energy flux density (EFD) ESWT in the left hip, respectively, whereas group C (n = 23) patients served as controls without the ESWT treatment. All patients self-administered alendronate sodium tablets orally for a year. The BMD of the lumbar spine (L2-L4), femoral neck, great tuberosity, and total left hip was measured before ESWT treatment and at 3, 6, and 12 months using dual energy X-ray absorptiometry (DEXA).

RESULTS

At 12 months, the lumbar spine, femoral neck, great tuberosity, and total left hip BMD in all patients had increased (p < 0.01). The increase in lumbar spine BMD in group A patients was higher than that in group B patients (p = 0.03); other between-group differences were not observed (p = 0.73, group A vs. C; p = 0.06, group B vs. C). The femoral neck, great tuberosity, and total left hip BMD increases in group B patients were higher than that in either group A or C (p < 0.01, group B vs. A; p < 0.01, group A vs. C).

CONCLUSION

This study showed that ESWT could efficiently improve the local BMD; relatively, the high dosage was effective.

Establishing the Basis for Mechanobiology-Based Physical Therapy Protocols to Potentiate Cellular Healing and Tissue Regeneration

Life is mechanobiological: mechanical stimuli play a pivotal role in the formation of structurally and functionally appropriate body templates through mechanobiologically-driven cellular and tissue re/modeling. The body responds to mechanical stimuli engendered through physical movement in an integrated fashion, internalizing and transferring forces from organ, through tissue and cellular length scales. In the context of rehabilitation and therapeutic outcomes, such mechanical stimuli are referred to as mechanotherapy. Physical therapists use mechanotherapy and mechanical interventions, e.g., exercise therapy and manual mobilizations, to restore function and treat disease and/or injury. While the effect of directed movement, such as in physical therapy, is well documented at the length scale of the body and its organs, a number of recent studies implicate its integral effect in modulating cellular behavior and subsequent tissue adaptation. Yet the link between movement biomechanics, physical therapy, and subsequent cellular and tissue mechanoadaptation is not well established in the literature. Here we review mechanoadaptation in the context of physical therapy, from organ to cell scale mechanotransduction and cell to organ scale extracellular matrix genesis and re/modeling. We suggest that physical therapy can be developed to harness the mechanosensitivity of cells and tissues, enabling prescriptive definition of physical and mechanical interventions to enhance tissue genesis, healing, and rehabilitation.

Combination of biochemical and mechanical cues for tendon tissue engineering

Tendinopathies negatively affect the life quality of millions of people in occupational and athletic settings, as well as the general population. Tendon healing is a slow process, often with insufficient results to restore complete endurance and functionality of the tissue. Tissue engineering, using tendon progenitors, artificial matrices and bioreactors for mechanical stimulation, could be an important approach for treating rips, fraying and tissue rupture. In our work, C3H10T1/2 murine fibroblast cell line was exposed to a combination of stimuli: a biochemical stimulus provided by Transforming Growth Factor Beta (TGF-β) and Ascorbic Acid (AA); a three-dimensional environment represented by PEGylated-Fibrinogen (PEG-Fibrinogen) biomimetic matrix; and a mechanical induction exploiting a custom bioreactor applying uniaxial stretching. In vitro analyses by immunofluorescence and mechanical testing revealed that the proposed combined approach favours the organization of a three-dimensional tissue-like structure promoting a remarkable arrangement of the cells and the neo-extracellular matrix, reflecting into enhanced mechanical strength. The proposed method represents a novel approach for tendon tissue engineering, demonstrating how the combined effect of biochemical and mechanical stimuli ameliorates biological and mechanical properties of the artificial tissue compared to those obtained with single inducement.