Glucocorticoids inhibit tenocyte proliferation and Tendon progenitor cell recruitment

Skin closUre in carPal tunnEl Release (SUPER): protocol for a blinded randomised controlled trial comparing absorbable and non-absorbable sutures in carpal tunnel release

INTRODUCTION

Carpal tunnel syndrome is a common disorder affecting a substantial portion of the general population. Surgical intervention is often deemed necessary, with the median nerve release being one of the most frequent operations. Optimising all the aspects of this procedure can enhance patient satisfaction with the treatment.

METHODS AND ANALYSIS

We aim to determine the differences in the aesthetic outcome of the scar as well as the pain experienced during the healing process between the use of absorbable and non-absorbable sutures. The primary outcome measure will be the patients' subjective satisfaction with the aesthetic appearance of the scar 1 year after the operation. Secondary outcomes will include a similar evaluation of the aesthetics performed by a blinded outcome assessor, as well as pain experienced by the patients during the 2 weeks postoperatively. The severity and improvement of the patients' symptoms will also be measured by a Finnish version of the Boston Carpal Tunnel Questionnaire. Costs will be evaluated for both groups. Safety of the wound closure will be followed and reported.

ETHICS AND DISSEMINATION

This protocol was approved by the Research Ethics Committee of the Northern Savo Hospital District (2319/2021). The trial will be conducted in accordance with the principles of Good Clinical Practice and the Declaration of Helsinki. The results will be disseminated through publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05503719.

Total Healing of a Partial Rupture of the Supraspinatus Tendon Using Barbotage Technique Associated with Platelet-Rich Plasma: A Randomized, Controlled, and Double-Blind Clinical Trial

The prevalence of partial rotator cuff tears (PRCTs) is high in the general population. Our hypothesis is that barbotage, when associated with platelet-rich plasma (PRP), is an effective method for healing these tears. The aim of this study was to compare the effects of barbotage with or without PRP on the healing of partial supraspinatus tendon tears (PSTTs). This study assessed the Western Ontario Rotator Cuff Index score and ultrasound (US) images at 6 weeks and 6 months after treatment. Patients in both groups showed clinical improvement, with no significant difference in scores at 6 weeks. However, at 6 months, the PRP group exhibited significant improvement (p = 0.019). Both groups experienced a reduction in ST tear size, but the PRP group demonstrated a significant enhancement at 6 weeks and 6 months. In conclusion, the US-guided barbotage technique, whether associated with PRP or saline solution, proved to be an effective treatment for clinical improvement and reduction in the size of PSTT. Better clinical improvement results were observed with PRP at 6 months. The combination of PRP with barbotage was superior in reducing the size of the ST tear at both 6 weeks and 6 months, resulting in complete healing in 79.3% of the tears.

Dexamethasone Is Not Sufficient to Facilitate Tenogenic Differentiation of Dermal Fibroblasts in a 3D Organoid Model

Self-assembling three-dimensional organoids that do not rely on an exogenous scaffold but maintain their native cell-to-cell and cell-to-matrix interactions represent a promising model in the field of tendon tissue engineering. We have identified dermal fibroblasts (DFs) as a potential cell type for generating functional tendon-like tissue. The glucocorticoid dexamethasone (DEX) has been shown to regulate cell proliferation and facilitate differentiation towards other mesenchymal lineages. Therefore, we hypothesized that the administration of DEX could reduce excessive DF proliferation and thus, facilitate the tenogenic differentiation of DFs using a previously established 3D organoid model combined with dose-dependent application of DEX. Interestingly, the results demonstrated that DEX, in all tested concentrations, was not sufficient to notably induce the tenogenic differentiation of human DFs and DEX-treated organoids did not have clear advantages over untreated control organoids. Moreover, high concentrations of DEX exerted a negative impact on the organoid phenotype. Nevertheless, the expression profile of tendon-related genes of untreated and 10 nM DEX-treated DF organoids was largely comparable to organoids formed by tendon-derived cells, which is encouraging for further investigations on utilizing DFs for tendon tissue engineering.

Histological and Biomechanical Effects of Local Anesthetics and Steroids on Achilles Tendon: A Study in Rats

BACKGROUND

Peritendinous injection of local anesthetics, alone or in combination with corticosteroids, is widely used in the treatment of tendinopathies. Toxicity of local anesthetics has been demonstrated in many cells, including myocytes, chondrocytes, and neurons. Bupivacaine and lidocaine are known to have time- and dose-dependent cytotoxicity in these cells. The effects of these agents on the tendon remain unknown.

PURPOSE

To show histological and biomechanical effects after the injection of different local anesthetics and steroids, both single and combined, at different concentrations into the peritendinous sheath of rat Achilles tendon.

STUDY DESIGN

Controlled laboratory study.

METHODS

In the study, 100 rats were divided into 10 groups with equal body weights. Inflammation was induced in both Achilles tendons of each rat by means of the ball drop technique; 7 hours later, injections were made into the peritendinous sheaths of both Achilles tendons using lidocaine, bupivacaine, and dexamethasone as appropriate for the rat's group. At the end of the first week, the right Achilles tendons of the rats were removed for histological study. Left Achilles tendons were evaluated in terms of biomechanics.

RESULTS

Histological findings demonstrated that the group with the most toxicity to the tendon was the group that received injection of dexamethasone alone. The groups with the least toxicity were those receiving dexamethasone combined with low- or high-dose bupivacaine. Biomechanical findings showed that the experimental groups had similar results to each other with the exception of the groups receiving 0.25% bupivacaine alone and dexamethasone alone, in which tendons revealed higher tensile strength.

CONCLUSION

Local anesthetic and steroid applications have different histological and biomechanical effects on the tendon. Although the dexamethasone-injected group was the most affected in terms of histology, these changes could not be demonstrated biomechanically.

CLINICAL RELEVANCE

In future clinical studies, the effect of steroids on the tendon should be investigated more comprehensively. Whether biomechanical results overlap with histological results should be investigated further.

Cross-Linked Hyaluronate and Corticosteroid Combination Ameliorate the Rat Experimental Tendinopathy through Anti-Senescent and -Apoptotic Effects

The combination of cross-linked hyaluronate (cHA) and corticosteroid showed more rapid pain or functional improvement in knee osteoarthritis and adhesive capsulitis. However, rare evidence of this combination in treating tendinopathy has been reported. We hypothesized that the specific formulations of cHA and dexamethasone (DEX) conferred amelioration of tendinopathy via anti-apoptosis and anti-senescence. In this controlled laboratory study, primary tenocytes from the human tendinopathic long head of biceps were treated with three cHA formulations (cHA:linealized HA = 80:20, 50:50, and 20:80) + DEX with or without IL-1β stimulation. Cell viability, inflammatory cytokines, tendon-related proliferation markers, matrix metalloproteinases (MMPs), senescent markers, and apoptosis were examined. The in vivo therapeutic effects of the selected cHA + DEX combinations were evaluated in a collagenase-induced rat patellar tendinopathy model. The expression levels of inflammatory mediators, including IL-1β, IL-6, COX-2, MMP-1, and MMP-3 were significantly reduced in all cHA + DEX-treated tenocytes (p < 0.05, all). The cHA (50:50) + DEX and cHA (20:80) + DEX combinations protected tenocytes from cytotoxicity, senescence, and apoptosis induced by DEX in either IL-1β stimulation or none. Furthermore, the two combinations significantly improved the rat experimental tendinopathy by reducing ultrasound feature scores and histological scores as well as the levels of apoptosis, senescence, and senescence-associated secretory phenotypes (p < 0.05, all). We identified two specific cHA formulations (cHA (50:50) and cHA (20:80)) + DEX that could ameliorate tendinopathy through anti-senescence and -apoptosis without cytotoxicity. This study provides a possible approach to treating tendinopathy using the combination of two well-known agents.

Repeated magnetic resonance imaging at 6 follow-up visits over a 2-year period after platelet-rich plasma injection in patients with lateral epicondylitis

BACKGROUND

The efficacy of platelet-rich plasma (PRP) for lateral epicondylitis has been demonstrated. However, the healing process monitored by repeated magnetic resonance imaging (MRI) is unclear. The purpose of this study was to evaluate sequential changes using MRI in patients with lateral epicondylitis treated by PRP injection at 6 follow-up visits over a 2-year period.

METHODS

Thirty patients who underwent PRP treatment for lateral epicondylitis and sequential MRI evaluation were prospectively enrolled. The MRI scores (ranging from 0 to 3) and clinical scores, including the visual analog scale (VAS) pain score and Patient-Rated Tennis Elbow Evaluation (PRTEE) score, were measured at baseline (before treatment) and 1, 3, 6, 12, 18, and 24 months after the procedure. Sequential changes in the MRI scores and clinical scores during the treatment period were evaluated. In addition, the associations between MRI scores and clinical scores were assessed.

RESULTS

The mean MRI score at baseline was 2.30, and the mean MRI scores at 1, 3, 6, 12, 18, and 24 months after the procedure were 1.97, 1.77, 1.13, 0.73, 0.60, and 0.33, respectively. Significant improvements in the MRI scores occurred by 3 months and continued over a period of 24 months. Regarding the clinical scores, the mean VAS pain scores were 72 at baseline, 48 at 1 month, 34 at 3 months, 28 at 6 months, 15 at 12 months, 14 at 18 months, and 11 at 24 months and the mean PRTEE scores were 56, 36, 26, 18, 8, 9, and 6, respectively. Significant improvements in the VAS pain score and PRTEE score occurred by 1 month and continued over a period of 12 months. There was little association between the MRI scores and clinical scores.

CONCLUSIONS

Continuous tendon recovery assessed by MRI was found during a 2-year period after PRP treatment. Improvements in the MRI scores followed and continued longer than improvements assessed by the clinical scores.

Effects of Sodium Hyaluronate in the Treatment of Rotator Cuff Lesions: A Systematic Review and Meta-analysis

Background:

Rotator cuff pathology is a common cause of pain and shoulder dysfunction. Several nonoperative treatment modalities have been developed for rotator cuff lesions, but their relative efficacy is not well-established.

Purpose/Hypothesis:

The purpose of this systematic review and meta-analysis was to evaluate the efficacy and safety of sodium hyaluronate (SH) in the treatment of patients with rotator cuff lesions. It was hypothesized that SH would be found to be more effective than other nonoperative regimens.

Study Design:

Systematic review; Level of evidence, 3.

Methods:

We searched various databases to identify eligible studies that evaluated the effects of SH on the pain and shoulder dysfunction attributed to rotator cuff lesions. Outcome measures were pain visual analog scale (VAS) score; Constant score; University of California, Los Angeles (UCLA) score; satisfaction rate; complications; and factors affecting the pain VAS score. Outcomes were reported as weighted mean difference (WMD) or risk ratio.

Results:

A total of 9 studies were identified for data analysis. Compared with patients treated with other nonoperative treatments (controls), those treated with SH had significantly improved pain VAS scores at 1 week (WMD = −0.95; 95% CI, −1.75 to −0.16; P = .019), 2 weeks (WMD = −1.05; 95% CI, −2.07 to −0.03; P = .044), 3 weeks (WMD = −1.49; 95% CI, −2.88 to −0.11; P = .035), and 4 weeks (WMD = −2.12; 95% CI, −4.05 to −0.19; P = .031). The Constant score was significantly improved in the SH group versus controls at 2 weeks (WMD = 3.25; 95% CI, 2.36 to 4.13; P < .001), 3 months (WMD = 20.28; 95% CI, 0.54 to 40.03; P = .044), and 6 months (WMD = 5.58; 95% CI, 0.94 to 10.21; P = .018). The UCLA score and satisfaction rate did not differ significantly between the 2 groups. No complications associated with SH were reported in the included studies. Metaregression analysis showed that, except for study design (coefficient = −1.64; 95% CI, −2.64 to −0.63; P = .002), none of the variables (sample size, tear type, control treatments) significantly predicted the difference in VAS pain score between SH and other treatments.

Conclusion:

The present meta-analysis demonstrated that SH was effective in treating patients with rotator cuff lesions.

The use of platelet-rich plasma therapy in treating tennis elbow: A critical review of randomised control trials

Tennis elbow (TE) is a painful and debilitating condition of the elbow. Recently, the use of orthobiologics, such as platelet-rich-plasma (PRP), has been proposed to promote tendon regeneration. Despite their popularity, there is a paucity of updated reviews on the use of PRP compared with other treatment modalities for treating TE. The aim of this review is to summarise high quality studies that compare the use of PRP therapy with other therapies for TE and to identify areas where further research is warranted. This systematic review was performed in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. A comprehensive literature search of PubMed, Scopus and Cochrane Library databases was undertaken in May 2021. Articles were screened for the following criteria: randomised control trials (RCTs) involving PRP in at least one of the treatment arms for tennis elbow. The quality of the RCTs included were analysed for their risk of bias using the modified Cochrane Collaboration Risk of Bias Assessment Tool for randomised trials. A total of 20 RCTs of which 1520 TE patients were analysed. The RCTs included in this review compared PRP with various treatment modalities routinely used in clinical practice such as physiotherapy, steroid injections, Autologous Whole Blood (AWB) and surgical interventions. With regards to the quality of RCTs, collectively, selection bias was found to be low risk however, performance bias in terms of blinding of participants and personnel performed poorly. Of the 20 RCTs, only 5 studies were classified as low risk of bias. In these 5 studies, 2 RCTs compared PRP with steroids and reported contrasting results, 1 RCT compared PRP with AWB injections which reported both to be similarly efficacious, 3 RCTs included a placebo group and only 1 reported superior effects with PRP. There are 2 main types of PRP classified according to the number of pro-inflammatory leukocyte i.e. leukocyte-rich and leukocyte-poor PRP. However, only 8 studies documented the formulation of PRP used. While the heterogeneity of PRP formulations could in-part explain the reported differences in outcomes, overall there is limited robust evidence to recommend PRP therapy for TE. Further research is required to establish the optimal formulation and administration of PRP injections. Proper documentation of TE patients need to be standardised before concrete recommendations on the use of PRP therapy may be offered.

Cell-based therapy of the elbow: evidence for lateral tendinopathy-a review on current treatments

PURPOSE

Cell-based therapies are on the rise in treating intra and extraarticular pathologies, trying to avoid surgical intervention and support local repair processes. Therefore, the aim was to summarize current evidence-based treatment options for a cell-based therapy around the elbow.

METHODS

Through a literature review up-to date treatment algorithms and therapies have been identified and have been rated according to their evidence level for clinical recommendation.

RESULTS

Regarding the four extraarticular anatomical regions of the elbow (anterior, medial, posterior and lateral) and the joint itself, the lateral elbow and its´ tendinopathies as well as the use of cell-based treatment options have been extensively studied and, therefore, allow for clear and evidence-based recommendations. The remaining three regions as wells as the intraarticular application do not show enough evidence for a clinical recommendation.

CONCLUSION

In conclusion the cell-based approach for treating elbow pathologies can only be recommended for the lateral elbow, as there has been shown sufficient evidence for the extraarticular application. It has to be mentioned, that the results from the lateral elbow maybe transferred to other extra-articular tendinopathies, as the lack of evidence may be due to the rare appearance of posterior, medial and anterior tendon affection. No recommendation can be given for intra-articular use.

LEVEL OF EVIDENCE

IV.

Restorative and pain-relieving effects of fibroin in preclinical models of tendinopathy

The term tendinopathy indicates a wide spectrum of conditions characterized by alterations in tendon tissue homeostatic response and damage to the extracellular matrix. The current pharmacological approach involves the use of nonsteroidal anti-inflammatory drugs and corticosteroids often with unsatisfactory results, making essential the identification of new treatments. In this study, the pro-regenerative and protective effects of an aqueous fibroin solution (0.5-500 μg/mL) against glucose oxidase (GOx)-induced damage in rat tenocytes were investigated. Then, fibroin anti-hyperalgesic and protective actions were evaluated in two models of tendinopathy induced in rats by collagenase or carrageenan injection, respectively. In vitro, 5-10 μg/mL fibroin per se increased cell viability and reverted the morphological alterations caused by GOx (0.1 U/mL). Fibroin 10 μg/mL evoked proliferative signaling upregulating the expression of decorin, scleraxin, tenomodulin (p < 0.001), FGF-2, and tenascin-C (p < 0.01) genes. Fibroin enhanced the basal FGF-2 and MMP-9 protein concentrations and prevented their GOx-mediated decrease. Furthermore, fibroin positively modulated the production of collagen type I. In vivo, the peri-tendinous injection of fibroin (5 mg) reduced the development of spontaneous pain and hypersensitivity (p < 0.01) induced by the intra-tendinous injection of collagenase; the efficacy was comparable to that of triamcinolone. The pain-relieving action of fibroin (peri-tendinous) was confirmed in the model of tendinopathy induced by carrageenan (intra-tendinous) where this fibrous protein was also able to improve tendon matrix organization, normalizing the orientation of collagen fibers. In conclusion, the use of fibroin in tendinopathies is suggested taking advantage of its excellent mechanical properties, pain-relieving effects, and ability to promote tissue regeneration processes.

Systematic investigation and comparison of US FDA-approved immunosuppressive drugs FK506, cyclosporine and rapamycin for neuromuscular regeneration following chronic nerve compression injury

Aim: To compare therapeutic benefits of different immunophilin ligands for treating nerve injuries. Materials & methods: Cyclosporine, FK506 and rapamycin, were evaluated first in vitro on a serum-free culture of embryonic dorsal root ganglia followed by a new in vivo model of chronic nerve compression. Results: Outcomes of the in vitro study have shown a potent effect of cyclosporine and FK506, on dorsal root ganglia axonal outgrowth, comparable to the effect of nerve growth factor. Rapamycin exhibited only a moderate effect. The in vivo study revealed the beneficial effects of cyclosporine, FK506 and rapamycin for neuromuscular regeneration. Cyclosporine showed the better maintenance of the tissues and function. Conclusion: Cyclosporine, FK506 and rapamycin drugs showed potential for treating peripheral nerve chronic compression injuries.

A new model of chronic peripheral nerve compression for basic research and pharmaceutical drug testing

Aim: To develop a consistent model to standardize research in the field of chronic peripheral nerve neuropathy. Methods: The left sciatic nerve of 8-week-old Sprague-Dawley rats was compressed using a customized instrument leaving a defined post injury nerve lumen (400 μm, 250 μm, 100 μm, 0 μm) for 6 weeks. Sensory and motor outcomes were measured weekly, and histomorphology and electrophysiology after 6 weeks. Results: The findings demonstrated compression depth-dependent sensory and motor pathologies. Quantitative measurements revealed a significant myelin degeneration, axon irregularities and muscle atrophy. At the functional level, we highlighted the dynamics of the different injury profiles. Conclusion: Our novel model of chronic peripheral nerve compression is a useful tool for research on pathophysiology and new therapeutic approaches.

A Maternal High Fat Diet Leads to Sex-Specific Programming of Mechanical Properties in Supraspinatus Tendons of Adult Rat Offspring

Background: Over half of women of reproductive age are now overweight or obese. The impact of maternal high-fat diet (HFD) is emerging as an important factor in the development and health of musculoskeletal tissues in offspring, however there is a paucity of evidence examining its effects on tendon. Alterations in the early life environment during critical periods of tendon growth therefore have the potential to influence tendon health that cross the lifespan. We hypothesised that a maternal HFD would alter biomechanical, morphological and gene expression profiles of adult offspring rotator cuff tendon. Materials and Methods: Female Sprague-Dawley rats were randomly assigned to either: control diet (CD; 10% kcal or 43 mg/g from fat) or HFD (45% kcal or 235 mg/g from fat) 14 days prior to mating and throughout pregnancy and lactation. Eight female and male offspring from each maternal diet group were weaned onto a standard chow diet and then culled at postnatal day 100 for tissue collection. Supraspinatus tendons were used for mechanical testing and histological assessment (cellularity, fibre organisation, nuclei shape) and tail tendons were collected for gene expression analysis. Results: A maternal HFD increased the elasticity (Young's Modulus) in the supraspinatus tendon of male offspring. Female offspring tendon biomechanical properties were not affected by maternal HFD. Gene expression of SCX and COL1A1 were reduced in male and female offspring of maternal HFD, respectively. Despite this, tendon histological organisation were similar between maternal diet groups in both sexes. Conclusion: An obesogenic diet during pregnancy increased tendon elasticity in male, but not female, offspring. This is the first study to demonstrate that maternal diet can modulate the biomechanical properties of offspring tendon. A maternal HFD may be an important factor in regulating adult offspring tendon homeostasis that may predispose offspring to developing tendinopathies and adverse tendon outcomes in later life.

Effect of Platelet-Rich Plasma Injection on Mild or Moderate Carpal Tunnel Syndrome: An Updated Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective

To evaluate efficacy of platelet-rich plasma (PRP) injection in carpal tunnel syndrome (CTS), we conducted this meta-analysis, as well as proposed a protocol for its application in curative processes.

Methods

All randomized controlled trials (RCTs) of PRP for the management of mild or moderate CTS were included in this study. Database search was conducted from study inception to July 2020, including PubMed, Embase, Web of Science, and Cochrane Library. We used visual analogue scores (VAS) and the Boston Carpal Tunnel Questionnaire (BCTQ) as evaluation tools for primary outcomes. Second outcomes comprised cross-sectional area (ΔCSA) and electrophysiological indexes including distal motor latency (DML), sensory peak latency (SPL), motor nerve conduction velocity (MNCV), sensory nerve conduction velocity (SNCV), compound muscle action potential (CMAP), and sensory nerve action potential (SNAP). The pooled data were analyzed using RevMan 5.3. Subgroup and sensitivity analyses were conducted with the evidence of heterogeneity. Egger' test was used to investigate publication bias.

Results

9 RCTs were finally screened out with 434 patients included. Control groups comprised corticosteroid injection in 5 trials, saline injection in 1 trial, and splint in 3 trials. At the 1st month after follow-up, only ΔCSA between the PRP group and the control group showed significant difference (P < 0.05). In the 3rd month, there were statistically significant differences in VAS, BCTQ, SPL, SNCV, and ΔCSA between two groups (P < 0.05), while no statistically significant differences were found in the remaining outcomes. In the 6th month, there were statistically significant differences at BCTQ (P < 0.05) in primary outcomes and ΔCSA (P < 0.05) in secondary outcomes between two groups. As to adverse events in PRP injection, only one study reported increased pain sensation within 48 h after injections.

Conclusion

This systematic review and meta-analysis demonstrates that the PRP could be effective for mild to moderate CTS and superior to traditional conservative treatments in improving pain and function and reducing the swelling of the median nerve for a mid-long-term effect. To some extent, the electrophysiological indexes also improved after PRP injection compared with others conservative treatments.

How periarticular corticosteroid injections impact the integrity of arthroscopic rotator cuff repair

INTRODUCTION

Multimodal analgesic (MMA) injections combined with corticosteroids have recently been shown to be effective for managing pain after arthroscopic rotator cuff repair.

HYPOTHESIS

The goal of this study was to analyze the effects of corticosteroid injections on the integrity of tendon repairs using magnetic resonance imaging (MRI). The hypothesis was that MMA injections combined with corticosteroids have no deleterious effects on functional outcomes and tendon healing 1 year after surgical rotator cuff repair.

METHODS

This was a prospective, double-blind study of 50 patients undergoing arthroscopic rotator cuff repair who were randomized into two groups. The study group (n=25) received a periarticular injection of a mixture of ropivacaine, morphine and methylprednisolone at the end of the procedure. The control group (n=25) received a placebo injection. The clinical outcomes were the pain level and complications, while the functional outcomes consisted of the Constant-Murley Score (CMS), American Shoulder and Elbow Surgeons Shoulder (ASES) score and Simple Shoulder Test (SST). The structural integrity of the operated tendons was analyzed on MRI at a mean follow-up of 15.1±1.3 months for the study group and 15.2±1.1 for the control group (p=0.848).

RESULTS

Pain on a visual analog scale was significantly reduced in both groups after the surgery. Nevertheless, there was no significant difference between groups at the final follow-up visit (p=0.803). Compared to the preoperative values, the CMS, ASES and SST significantly improved in both groups after surgery but were not significantly different between groups at the final assessment (p=0.801, 0.869 and 0.769, respectively). MRI revealed supraspinatus tendon retears in 16% of patients in the study group and 36% in the control group (p=0.107). There were no infections in the study group as of the final assessment. Advanced age (p=0.049), diabetes (p<0.01) and posterior extension of the tear (p=0.039) negatively impact healing. Corticosteroid injection did not negatively impact healing (p=0.197).

CONCLUSION

This study shows that MMA injection combined with corticosteroids does not alter the tendon healing, clinical outcomes, or functional outcomes 1 year after arthroscopic rotator cuff repair. It remains a safe and effective analgesia method during rotator cuff repair surgery.

LEVEL OF EVIDENCE

II, low-powered placebo-controlled, randomized study.

Platelet-rich plasma for treatment of chronic proximal hamstring tendinopathy

Aim: To determine whether platelet-rich plasma (PRP) can successfully treat symptoms associated with proximal hamstring tendinopathy. Materials & methods: Charts were retrospectively reviewed of patients with a diagnosis of chronic proximal hamstring tendinopathy who underwent an ultrasound-guided leukocyte-rich PRP injection to assess reported outcomes at baseline and final follow-up post-intervention. Results: In 22 patients with a mean age of 48.7 years and mean symptom duration of 26.5 months, mean Numeric Pain Rating Scale and Victorian Institute of Sport Assessment Scale for Proximal Hamstring Tendinopathy subscores demonstrated statistically significant improvements (p < 0.05) at a mean of 7.91 months follow-up. Sixty-eight percent of patients demonstrated ≥50% reduction of pain. Conclusion: Pain and functional outcomes improved following injection of PRP.

Nonbiologic Injections in Sports Medicine

Nonbiologic medications (local anesthetics, corticosteroids, and nonsteroidal anti-inflammatory drugs) are commonly administered to athletes for analgesia after injury. However, the risks of nonbiologic injections often are overlooked simply because of their long-term market availability. A thorough understanding of the mechanism of action, the reported benefits, and the potential risks of nonbiologic medications is crucial prior to their use, especially in the treatment of young athletes. Sports medicine physicians and surgeons must be aware of the systemic and local effects of these medications to ensure an appropriate drug choice that minimizes side effects and avoids recently reported toxicity to myocytes, tenocytes, and chondrocytes.

Dexamethasone causes calcium deposition and degeneration in human anterior cruciate ligament cells through endoplasmic reticulum stress

BACKGROUND

Dexamethasone is widely used in the treatment of joint diseases due to its anti-inflammatory properties. However, it can cause serious adverse effects. The anterior cruciate ligament (ACL) is an important stabilizer of the knee joint. However, the effect of dexamethasone treatment on the ACL is unclear.

OBJECTIVE

This study aims to explore the effects of dexamethasone on ACL tissues and cells through in vitro and in vivo experiments.

RESULTS

In vitro, we found that after treatment with dexamethasone, human ACL cell apoptosis was increased, type I collagen (COL1A1) content was decreased, mineralization related genes (ENPP1 and ANKH) and calcified nodules were increased, and endoplasmic reticulum stress (ERS) was enhanced. However, ERS inhibitors could significantly inhibit the increase in calcification and the decrease in COL1A1 induced by dexamethasone. In vivo, Wistar rats received the infra-articular injection with dexamethasone (0.5 mg/kg) for 8 weeks. We found that dexamethasone treatment decreased the COL1A1 content and increased the COL2A1 content in the ACL tissues of rats and that chondroid differentiation and mineralization occurred. Meanwhile, the expression of ERS-related proteins was increased.

CONCLUSION

Dexamethasone increased the calcification of ACL cells and caused ACL degeneration through ERS, suggesting that long-term treatment with dexamethasone may cause adverse effects on ACL tissue and increase the risk of long-term rupture.

The Susceptibility of Tenocytes from Different Ages of Donors Towards Dexamethasone and Ascorbic Acid can be Screened in a Microfluidic Platform

Hamstring tendon is one of the best graft choices for anterior cruciate ligament reconstruction. The upper age limit of reconstruction is not determined because tenocytes from old individuals have less proliferative ability than young ones. Dexamethasone is commonly used to deal with musculoskeletal disorder with dose-dependent cytotoxicity toward tenocytes. Ascorbic acid is essential for tenocytes culture and collagen secretion and can alleviate the cytotoxicity of dexamethasone. In the current study, a microfluidic platform was used to screen the best dexamethasone and ascorbic acid combination treatment for tenocytes from young and old donors because it has been proven to provide a high throughput analysis platform. Comparison of their proliferation under three concentrations of ascorbic acid and dexamethasone was performed. Tenocytes proliferation among young and old donors was also measured when exposed to nine combinations of ascorbic acid and dexamethasone. The result confirmed the differences in cells proliferation when hamstring tenocytes from different ages of donors are exposed to different concentrations of dexamethasone and ascorbic acid. Tenocytes from old donors are not always more susceptible to dexamethasone and ascorbic acid. An optimal dose of ascorbic acid in decreasing the cytotoxic effect of dexamethasone can be screened by a high throughput microfluidic platform.

The use of biologics for the elbow: a critical analysis review

There is significant interest in biologic treatment options to improve the healing environment and more rapidly decrease symptoms in many conditions around the elbow. Despite fairly widespread use of biologic agents such as platelet-rich plasma (PRP) in the elbow, there is a lack of clear evidence in the literature to support its use. The potential impact of these biologic agents must be evaluated with evidence from high-quality studies, particularly considering the high financial burden these treatments often impose on patients. The aim of this review is to provide an evidence-based summary of the biologic augmentation options available for use by the physician treating painful conditions of the elbow and to identify areas where further research is warranted.

Increased risk of symptomatic progression of instability following decompression for lumbar canal stenosis in patients receiving chronic glucocorticoids therapy

BACKGROUND

Lumbar decompression surgery is a commonly used treatment for degenerative lumbar spinal stenosis; however, some patients develop symptomatic spinal instability following decompression surgery. The objective of this study was to reveal risk factors for delayed instability following decompression surgery for lumbar spinal stenosis.

METHODS

One hundred ten patients who underwent single-level lumbar decompression between 2008 and 2014 were retrospectively reviewed. Surgical indication for decompression surgery was symptomatic lumbar canal stenosis without spondylolisthesis or with minimum spondylolisthesis (less than 4 mm translation). Patients with gross segmental motion (>10° in disc angle, >2 mm translation) on flexion-extension lumbar radiographs were excluded. Age, sex, body mass index, smoking history, diabetes mellitus, autoimmune connective tissue diseases including rheumatoid arthritis, and the use of glucocorticoids were investigated. Radiographic measurements included disc angle, disc height, slippage, facet angle, segmental motion (flexion-extension), lumbar alignment, facet effusion, and disc degeneration. Data were analyzed using multivariate forward selection stepwise logistic regression, chi-square tests, and Student t-test.

RESULTS

Six of 110 patients (5.5%) developed symptomatic spinal instability at the operative level and underwent spinal fusion surgery at an average of 2.1 years postoperatively. Autoimmune connective tissue disorders and chronic use of glucocorticoids were associated with the occurrence of symptomatic spinal instability requiring spine fusion surgery, while there was no significant difference in radiographic parameters and demographic factors excluding autoimmune connective tissue diseases between reoperation and non-reoperation groups.

CONCLUSIONS

Patients with autoimmune connective tissue disorders receiving chronic glucocorticoid therapy are more likely to develop symptomatic spinal instability following decompression surgery for lumbar canal stenosis without or with minimal spondylolisthesis.

[Problems of the diagnosis and treatment of compression neuropathy of the median nerve: an analysis of typical medical practice]

AIM

An analysis of typical medical errors in the diagnosis and treatment of compression neuropathy of the median nerve at the level of the wrist (carpal tunnel syndrome - CTS).

MATERIAL AND METHODS

Previous diagnoses and treatment of 85 patients with CTS (14 men and 71 women), aged from 36 to 84 years (middle age 62±10.6 years), who underwent surgery in our clinics were evaluated.

RESULTS

The wrong diagnosis was made in most of patients (60%). The osteochondrosis of cervical spine (45.8%) and diabetic polyneuropathy (5.8%) were the most common mistaken diagnoses. Proper neurophysiological measurements using the Phalen's test and Tinel's sign were not performed in the majority of patients. Magnetic resonance imaging (MRI) of the cervical spine was often unreasonably made, the electroneuromyography was not used. Nonsteroidal anti-inflammatory drugs (NSAIDs), vitamin B group were improperly prescribed to the patients diagnosed with CTS. Local corticosteroids injections were not prescribed to most of patients, immobilization of the wrist was not recommended at the early stage of disease and decompressive surgery at the advanced stage of disease. Clinical observation of the patient with long period of misdiagnosing is presented. Despite the long-standing history of CTS, surgical decompression led to regression of symptoms and complete professional rehabilitation.

CONCLUSION

It is necessary to inform physicians about manifestations, diagnostic criteria and effective methods of treatment of CTS.

Chronic lateral epicondylitis: challenges and solutions

Lateral epicondylitis (LE) is a significant source of pain and dysfunction resulting from repetitive gripping or wrist extension, radial deviation, and/or forearm supination. Although most cases are self-limiting over several years, controversy exists regarding the best treatment strategy for chronic LE. Nonsteroidal anti-inflammatory drugs (NSAIDs), physical therapy (PT), shockwave therapy, and injections with corticosteroids or biologics are all conservative treatment options for LE. For refractory cases, surgical options include open, arthroscopic, and percutaneous techniques. In this review, the current evidence behind these treatment strategies is presented. The data demonstrate that NSAIDs, PT, bracing, and shockwave therapy provide limited benefit for treating LE. Biologics such as platelet-rich plasma and autologous whole-blood injections may be superior to steroid injections in the long-term management of LE. Although the initial results are promising, larger comparative studies on stem cell injections are needed. For refractory LE, open, arthroscopic, and percutaneous techniques are all highly effective, with no method seemingly superior over another. Arthroscopic and percutaneous approaches may result in faster recovery and earlier return to work.

Rescue plan for Achilles: Therapeutics steering the fate and functions of stem cells in tendon wound healing

Due to the increasing age of our society and a rise in engagement of young people in extreme and/or competitive sports, both tendinopathies and tendon ruptures present a clinical and financial challenge. Tendon has limited natural healing capacity and often responds poorly to treatments, hence it requires prolonged rehabilitation in most cases. Till today, none of the therapeutic options has provided successful long-term solutions, meaning that repaired tendons do not recover their complete strength and functionality. Our understanding of tendon biology and healing increases only slowly and the development of new treatment options is insufficient. In this review, following discussion on tendon structure, healing and the clinical relevance of tendon injury, we aim to elucidate the role of stem cells in tendon healing and discuss new possibilities to enhance stem cell treatment of injured tendon. To date, studies mainly apply stem cells, often in combination with scaffolds or growth factors, to surgically created tendon defects. Deeper understanding of how stem cells and vasculature in the healing tendon react to growth factors, common drugs used to treat injured tendons and promising cellular boosters could help to develop new and more efficient ways to manage tendon injuries.

Development of a co-culture device for the study of human tenocytes in response to the combined stimulation of electric field and platelet rich plasma (PRP)

One of the objectives of rotator cuff repairs is to achieve biological healing and recovery in the tendon-bone zone. Some clinical evaluations reported the feasibility of tendon healing based on the stimulations of electric field and platelet-rich plasma (PRP). However, because of lack of appropriate tool for in vitro primary culture under complicated conditions, the efficacy and standard protocol of these healing approaches are still controversial among clinical experts. In this study, a novel co-culture device was developed for the study of tenocytes proliferation under single and combined stimulations of electric field and PRP. The device was a culture well divided into three sub-chambers separated by a barrier and embedded with a pair of parallel plate electrodes. Tenocytes and PRP gel could be respectively loaded into the sub-chambers and cultured with interlinked medium. Hence, tenocytes could concurrently receive a uniform electric field and platelet-derived growth factors by diffusion. Results revealed that the proliferation of tenocytes could be significantly enhanced by these stimulations. The device provides a precise and practical approach for the in vitro study of tendon healing, especially for PRP study. Moreover, optimization of the conditions of electric field and PRP could be determined by in vitro screening procedure before surgery to provide a personalized therapy.

Hamstring Injuries in the Athlete: Diagnosis, Treatment, and Return to Play

Hamstring injuries are very common in athletes. Acute hamstring strains can occur with high-speed running or with excessive hamstring lengthening. Athletes with proximal hamstring tendinopathy often do not report a specific inciting event; instead, they develop the pathology from chronic overuse. A thorough history and physical examination is important to determine the appropriate diagnosis and rule out other causes of posterior thigh pain. Conservative management of hamstring strains involves a rehabilitation protocol that gradually increases intensity and range of motion, and progresses to sport-specific and neuromuscular control exercises. Eccentric strengthening exercises are used for management of proximal hamstring tendinopathy. Studies investigating corticosteroid and platelet-rich plasma injections have mixed results. Magnetic resonance imaging and ultrasound are effective for identification of hamstring strains and tendinopathy but have not demonstrated correlation with return to play. The article focuses on diagnosis, treatment, and return-to-play considerations for acute hamstring strains and proximal hamstring tendinopathy in the athlete.

High-molecular-weight hyaluronic acid attenuated matrix metalloproteinase-1 and -3 expression via CD44 in tendinopathy

Evidence indicates that hyaluronic acid (HA) mitigates tendinopathy, but the effect of molecular weight is unclear. We investigated the effects of different concentrations and different molecular weights of HA (350 kDa, 1500 kDa, and 3000 kDa) on matrix metalloproteinase (MMP)-1 and -3 expression in IL-1β-stimulated rat tenocytes, and on their dynamic expression in peritendinous effusion from patients with long head of biceps (LHB) tendinopathy after high-molecular-weight (HMW)-HA treatments. Reverse transcription PCR, real-time PCR, and ELISA were used to determine MMP-1 and -3expression. Because CD44 was clearly expressed in the plasma membranes of cultured tenocytes, OX-50, a CD44 antagonist, was used to inhibit CD44 to evaluate the HA mechanism. HA (3000 kDa) significantly (p < 0.001) downregulated the mRNA and protein expression of MMP-1 and -3 in IL-1β-stimulated tenocytes. Its attenuating effects were dose-dependent (p < 0.01). In OX-50-pretreated cells, the mRNA expression of CD44 was not significantly altered, but the mRNA expression of MMP-1 and -3 was significantly upregulated. Visual analogue scale scores were significantly lower, and MMP-1 and -3 expression was significantly (p < 0.05) lower one month posttreatment. HMW-HA attenuated tendinopathy by downregulating MMP-1 and -3 expression. Inhibiting CD44 blocked the effects of HMW-HA.

Clinical benefits and drawbacks of local corticosteroids injections in tendinopathies

INTRODUCTION

local glucocorticoids injections are widely administered for the treatment of tendinopathies. positive results have been observed in some tendinopathies but not in others. moreover, worsening of symptoms, and even spontaneous tendon ruptures has been reported. the characteristics of the tendinopathies, the clinical peculiarities of the patient, and the technique used to administer glucocorticoids, can influence the therapeutic response. Areas covered: After reviewing the pertinent literature on the clinical results, basic information, both on the pathogenesis of tendinopathies and the effects of glucocorticoids on tendons, is reported. The pharmacological properties of glucocorticoids are useful to counteract some pathogenetic mechanisms of tendinopathies. However, several experimental studies suggest that the direct action of glucocorticoids on tendons is detrimental. Loss of collagen organization, impaired viability of fibroblasts, depletion of stem cells pool, and reduced mechanical properties have been observed. Expert opinion: Drawbacks of local glucocorticoids injections could be predicted on an individual basis, after a careful appraisal of patient characteristics and concomitant medications, along with the specific stage of tendon disease.

Platelet-rich plasma versus corticosteroid injections for carpal tunnel syndrome

BACKGROUND

Platelet-rich plasma therapy has the potential to promote peripheral nerve regeneration through the autologous supply of growth factors. Therefore, this study aimed to compare the effects of platelet-rich plasma injections with the effects of corticosteroid injections in the treatment of carpal tunnel syndrome.

METHODS

In total, 40 patients with mild carpal tunnel syndrome were equally divided into two groups. Nerve conduction studies were carried out, and the Boston Carpal Tunnel Questionnaire was administered to both groups before treatment. One group of patients received platelet-rich plasma injections, and the patients in the other group received corticosteroid injections into the carpal tunnel. The patients were followed for 6 months. After 3 and 6 months, the nerve conduction studies and the Boston Carpal Tunnel Questionnaire were repeated.

RESULTS

Although distal motor latencies did not change in either of the groups during the follow-up period, improvements in sensory nerve conduction were recorded after 3 months in both groups. However, there was no significant difference between the groups in the nerve conduction studies. In the Boston Carpal Tunnel Questionnaire, both the symptom severity score and the functional capacity score of the platelet-rich plasma group were significantly better than those of the corticosteroid group after 3 months, although there were no significant differences after 6 months.

CONCLUSIONS

Platelet-rich plasma injections may be considered for the temporary symptomatic relief of mild carpal tunnel syndrome.

Lateral Elbow Tendinopathy: Development of a Pathophysiology-Based Treatment Algorithm

Lateral elbow tendinopathy, commonly known as tennis elbow, is a condition that can cause significant functional impairment in working-age patients. The term tendinopathy is used to describe chronic overuse tendon disorders encompassing a group of pathologies, a spectrum of disease. This review details the pathophysiology of tendinopathy and tendon healing as an introduction for a system grading the severity of tendinopathy, with each of the 4 grades displaying distinct histopathological features. Currently, there are a large number of nonoperative treatments available for lateral elbow tendinopathy, with little guidance as to when and how to use them. In fact, an appraisal of the clinical trials, systematic reviews, and meta-analyses studying these treatment modalities reveals that no single treatment reliably achieves outstanding results. This may be due in part to the majority of clinical studies to date including all patients with chronic tendinopathy rather than attempting to categorize patients according to the severity of disease. We relate the pathophysiology of the different grades of tendinopathy to the basic science principles that underpin the mechanisms of action of the nonoperative treatments available to propose a treatment algorithm guiding the management of lateral elbow tendinopathy depending on severity. We believe that this system will be useful both in clinical practice and for the future investigation of the efficacy of treatments.

In vitro toxicity of local anaesthetics and corticosteroids on supraspinatus tenocyte viability and metabolism

Background/Objective

The purpose of this study was to evaluate supraspinatus tenocyte viability and metabolism in explants exposed to various local anaesthetics and corticosteroids. Our hypothesis was that the tendons exposed to these common injectates would have significantly decreased cell viability and metabolism compared with controls.

Methods

Supraspinatus tendon explants were obtained from dogs, placed in a culture media, and randomly assigned to one of the following groups: culture media only (control), 1% lidocaine, 0.5% lidocaine, 0.25% bupivacaine, 0.125% bupivacaine, 0.0625% bupivacaine, betamethasone acetate (5 mg), methylprednisolone acetate (40 mg), or triamcinolone acetonide (40 mg). Cell viability was determined on Days 1 and 7 after culture treatment using calcein AM (live cell) and Sytox Blue (dead cell) stains. Tissue metabolism was assessed on Days 1 and 7 using the resazurin blue metabolic assay. Significant differences were evaluated using a one-way analysis of variance with Tukey post hoc analysis.

Results

Compared with the controls, there were significant decreases in cell viability noted at Days 1 and 7 in tenocytes exposed to 1% lidocaine, betamethasone, and methylprednisolone. Significant decreases in cell metabolism were also noted at Days 1 and 7 in those groups. Treatment with 0.125% bupivacaine, 0.0625% bupivacaine, and triamcinolone demonstrated no decrease in cell viability or metabolism when compared with controls at any time point.

Conclusion

This data confirms that peritendinous injection of commonly used local anaesthetics and corticosteroids results in significant supraspinatus tenotoxicity in vitro. Further in vivo studies are required before making definitive clinical recommendations.

Deconstructing Chronic Low Back Pain in the Older Adult-Step by Step Evidence and Expert-Based Recommendations for Evaluation and Treatment. Part VIII: Lateral Hip and Thigh Pain

Objective. This article presents an evidence-based algorithm to assist primary care providers with the diagnosis and management of lateral hip and thigh pain in older adults. It is part of a series that focuses on coexisting pain patterns and contributors to chronic low back pain (CLBP) in the aging population. The objective of the series is to encourage clinicians to take a holistic approach when evaluating and treating CLBP in older adults.

Methods. A content expert panel and a primary care panel collaboratively used the modified Delphi approach to iteratively develop an evidence-based diagnostic and treatment algorithm. The panelists included physiatrists, geriatricians, internists, and physical therapists who treat both civilians and Veterans, and the algorithm was developed so that all required resources are available within the Veterans Health Administration system. An illustrative patient case was chosen from one of the author’s clinical practices to demonstrate the reasoning behind principles presented in the algorithm.

Results. An algorithm was developed which logically outlines evidence-based diagnostic and therapeutic recommendations for lateral hip and thigh pain in older adults. A case is presented which highlights the potential complexities of identifying the true pain generator and the importance of implementing proper treatment.

Conclusions. Lateral hip and thigh pain in older adults can contribute to and coexist with CLBP. Distinguishing the true cause(s) of pain from potentially a myriad of asymptomatic degenerative changes can be challenging, but a systematic approach can assist in identifying and treating some of the most common causes.

Role of the ERK1/2 Signaling Pathway in Osteogenesis of Rat Tendon-Derived Stem Cells in Normoxic and Hypoxic Cultures

BACKGROUND

Ectopic ossification and increased vascularization are two common phenomena in the chronic tendinopathic tendon. The increased vascularization usually leads to an elevated local oxygen tension which is one of micro-environments that can influence differentiate status of stem cells.

OBJECTIVE

This study aimed to investigate the osteogenesis capacity of rat tendon-derived stem cells TDSCs (rTDSCs) in normoxic and hypoxic cultures, and to study the role of ERK1/2 signaling pathway in this process.

METHODS

rTDSCs were subjected to osteogenesis inductive culture in hypoxic (3% O2) and normoxic (20% O2) conditions. The inhibitor U0126 was added along with culture medium to determine the role of ERK1/2 signaling pathway. Cell viability, cell proliferation, alizarin red staining, alkaline phosphatase (AKP) activity, gene expression (ALP, osteocalcin, collagen I and RUNX2) and protein expression (p-ERK1/2 and RUNX2) of osteogenic-cultured rTSDCs were analyzed in this study.

RESULTS

Hypoxic and normoxic culture had no effects on cell viability of rTDSCs, whereas the proliferation potential of rTDSCs was significantly increased in hypoxic culture. The osteogenesis capacity of rTDSCs in normoxic culture was significantly promoted compared with hypoxic culture, which was reflected by an increased alizarin red staining intensity, an elevated ALP activity, and the up-regulated gene (ALP, osteocalcin, collagen I and RUNX2) or protein (RUNX2) expression of osteogenic makers. However, the osteogenesis capacity of rTDSCs in both hypoxic and normoxic cultures was attenuated by the inhibitor U0126.

CONCLUSION

Normoxic culture promotes osteogenic differentiation of rTDSCs compared with the hypoxic culture, and the ERK1/2 signaling pathway is involved in this process.

Effects of corticosteroids and hyaluronic acid on torn rotator cuff tendons in vitro and in rats

Corticosteroids (CS) or hyaluronic acid (HA) is used in subacromial injection for the conservative treatment of rotator cuff tears (RCT); this study addresses the question of how CS and HA affect the tendon tissue and fibroblasts in vitro and in rats. Cell proliferation assays were performed in human tendon fibroblasts from RCT. Rats underwent surgery to create RCT, and the surgical sites were injected with CS or HA. The rotator cuff tendons were subjected to biomechanical testing, microscopic and immunohistochemical analysis of proliferating cell nuclear antigen (PCNA), and ultrastructural analysis. Cell proliferation was significantly decreased with CS in vitro (p < 0.05). Maximal load of CS-treated tendons was significantly decreased compared with that of HA-treated tendons (p < 0.05), as well as PCNA(+) cells at 2 weeks (p < 0.05). Ultrastructural observations of the CS-treated rats detected apoptosis of tendon fibroblasts 24 h after surgery. Histological and biomechanical data 4 weeks after surgery were not significant among the three groups. Unlike HA, CS caused cell death, and inhibition of the proliferation of tendon fibroblasts, leading to a delay of tendon healing involved and a subsequent decrease of biomechanical strength at the surgical site.

Perspectives in ultrasound-guided musculoskeletal interventions

Ultrasonography (USG) is a safe, easily available, and cost-effective modality, which has the additional advantage of being real time for imaging and image-guided interventions of the musculoskeletal system. Musculoskeletal interventions are gaining popularity in sports and rehabilitation for rapid healing of muscle and tendon injuries in professional athletes, healing of chronic tendinopathies, aspiration of joint effusions, periarticular bursae and ganglia, and perineural injections in acute and chronic pain syndromes. This article aims to provide an overview of the spectrum of musculoskeletal interventions that can be done under USG guidance both for diagnostic and therapeutic purposes.

Progress in cell-based therapies for tendon repair

The last decade has seen significant developments in cell therapies, based on permanently differentiated, reprogrammed or engineered stem cells, for tendon injuries and degenerative conditions. In vitro studies assess the influence of biophysical, biochemical and biological signals on tenogenic phenotype maintenance and/or differentiation towards tenogenic lineage. However, the ideal culture environment has yet to be identified due to the lack of standardised experimental setup and readout system. Bone marrow mesenchymal stem cells and tenocytes/dermal fibroblasts appear to be the cell populations of choice for clinical translation in equine and human patients respectively based on circumstantial, rather than on hard evidence. Collaborative, inter- and multi-disciplinary efforts are expected to provide clinically relevant and commercially viable cell-based therapies for tendon repair and regeneration in the years to come.

The past, present and future in scaffold-based tendon treatments

Tendon injuries represent a significant clinical burden on healthcare systems worldwide. As the human population ages and the life expectancy increases, tendon injuries will become more prevalent, especially among young individuals with long life ahead of them. Advancements in engineering, chemistry and biology have made available an array of three-dimensional scaffold-based intervention strategies, natural or synthetic in origin. Further, functionalisation strategies, based on biophysical, biochemical and biological cues, offer control over cellular functions; localisation and sustained release of therapeutics/biologics; and the ability to positively interact with the host to promote repair and regeneration. Herein, we critically discuss current therapies and emerging technologies that aim to transform tendon treatments in the years to come.

Effect of a single subacromial prednisolone injection in acute rotator cuff tears in a rat model

PURPOSE

This study examined the early effect of a subacromial steroid injection on injured rotator cuff tendon.

METHODS

Forty rats were allocated into two groups: a steroid injection (group 1) and no injection as control (group 2). A full-thickness defect was made at the unilateral infraspinatus tendon in both groups. A single dose of methylprednisolone was injected in steroid group. The tendon was harvested at 1, 3, 7, 14, and 42 days after surgery; gene expression and immunohistochemical study were performed for type-I/III collagen, tumour necrosis factor (TNF)-α, and extracellular matrix molecules.

RESULTS

The type-III to type-I collagen ratio was at 7 days higher in the steroid group than that in the control group and decreased to the control level at 14 days and was maintained until 42 days. The general expression of the MMPs and TIMPs between two groups showed similar pattern regardless of the steroid injection. The gene expression of aggrecan and fibronectin in the steroid group was significantly higher than that in the control group (p < 0.05) at 3 days after surgery. They decreased to the equal level with control group at 7 days after surgery. Both groups showed no significant difference between aggrecan and fibronectin until 42 days after surgery (n.s.).

CONCLUSIONS

A subacromial steroid injection may alter the collagen composition and extracellular matrix and interfere with the healing process in an acute tear of rat infraspinatus tendon at the early phase after the injection. However, these alterations seem to become normalized after the early inflammatory healing phase.

Dose- and time-dependent effects of triamcinolone acetonide on human rotator cuff-derived cells

Objectives

To investigate the appropriate dose and interval for the administration of triamcinolone acetonide (TA) in treating tendinopathy to avoid adverse effects such as tendon degeneration and rupture.

Methods

Human rotator cuff-derived cells were cultured using three media: regular medium (control), regular medium with 0.1 mg/mL of TA (low TA group), and with 1.0 mg/mL of TA (high TA group). The cell morphology, apoptosis, and viability were assessed at designated time points.

Results

In the low TA group, the cells became flattened and polygonal at seven days then returned to normal at 21 days. The cell apoptosis ratio and messenger ribonucleic acid expression of caspase-3, 7, 8, and 9 increased, and viability was reduced in the low and high groups at seven days. In the low TA group, apoptosis and viability returned to normal at 21 days, however, in the high TA group, the cell morphology, apoptosis ratio, caspase-3, 7, 8, and 9 and viability did not return by day 21. Re-administration was performed in the low TA group at 7-, 14-, and 21-day intervals, and cell viability did not return to the control level at the 7- and 14-day intervals.

Conclusion

A 0.1 mg/mL dose of TA temporarily decreased cell viability and increased cell apoptosis, which was recovered at 21 days, however, 1 mg/mL of TA caused irreversible damage to cell morphology and viability. An interval > three weeks was needed to safely re-administer TA. These findings may help determine the appropriate dose and interval for TA injection therapy.

Cite this article: Bone Joint Res 2014;3:328–34.

Conservative treatment of carpal tunnel syndrome: comparison between laser therapy and Fascial Manipulation(®)

The etiopathogenesis of Carpal Tunnel Syndrome (CTS) is multifactorial and most cases are classified as idiopathic (Thurston 2013). A randomized controlled trial was performed to compare the effectiveness of Fascial Manipulation(®) (FM) and Low-Level Laser Therapy (LLLT) for CTS. This prospective trial included 42 patients (70 hands with symptoms) with clinical and electroneuromyographic diagnosis of CTS. The patients were randomly assigned to receive multiple sessions of FM or multiple session of LLLT. The Visual Analogic Scale (VAS) and Boston Carpal Tunnel Questionnaire (BCTQ) were performed at baseline, end of treatment and after three months. The group that received FM showed a significant reduction in subjective pain perception and an increased function assessed by BCTQ at the end of the treatment and follow-up. The group that received LLLT showed an improvement in the BCTQ at the end of the treatment but the improvement level was not sustained at the three month follow-up. FM is a valid alternative treatment for CTS.

Current approaches for carpal tunnel syndrome

With advancement in biomechanical and biological research on idiopathic carpal tunnel syndrome, the insight on the pathophysiology of carpal tunnel syndrome has gained much clinical relevance. Open carpal tunnel release is still a gold standard procedure for carpal tunnel syndrome, which has evolved into mini-open procedure with development of new devices. Endoscopic carpal tunnel release has become popular in recent practice of hand surgery with an advantage of early recovery of hand function with minimal morbidity. However, endoscopic carpal tunnel release has its own limitation such as long learning curve with obvious surgical risk reported in the literature. In this review article, various treatment protocols for idiopathic carpal tunnel syndrome are presented with special highlight on endoscopic carpal tunnel release, which is gaining popularity in current practice.

The evaluation and treatment of rotator cuff pathology

Rotator cuff pathology accounts for most presentations of shoulder pain to primary care clinics. History and physical examination are important for excluding other causes of shoulder pain, while imaging assists in confirming the diagnosis and defining the severity of the abnormality. Treatment options include nonsteroidal anti-inflammatory agents, subacromial corticosteroid injections, and exercise therapy. Surgical intervention is generally reserved for those failing nonoperative measures and/or healthy, young, and middle-aged adults with full-thickness rotator cuff tears. No surgical technique has proved to be superior. Despite surgery, about 20% of patients experience retears, more likely occurring in those with larger tears.

Glucocorticoids induce senescence in primary human tenocytes by inhibition of sirtuin 1 and activation of the p53/p21 pathway: in vivo and in vitro evidence

Cellular senescence is an irreversible side effect of some pharmaceuticals which can contribute to tissue degeneration.

OBJECTIVE

To determine whether pharmaceutical glucocorticoids induce senescence in tenocytes.

METHODS

Features of senescence (β-galactosidase activity at pH 6 (SA-β-gal) and active mammalian/mechanistic target of rapamycin (mTOR) in cell cycle arrest) as well as the activity of the two main pathways leading to cell senescence were examined in glucocorticoid-treated primary human tenocytes. Evidence of senescence-inducing pathway induction in vivo was obtained using immunohistochemistry on tendon biopsy specimens taken before and 7 weeks after subacromial Depo-Medrone injection.

RESULTS

Dexamethasone treatment of tenocytes resulted in an increased percentage of SA-βgal-positive cells. Levels of phosphorylated p70S6K did not decrease with glucocorticoid treatment indicating mTOR remained active. Increased levels of acetylated p53 as well as increased RNA levels of its pro-senescence effector p21 were evident in dexamethasone-treated tenocytes. Levels of the p53 deacetylase sirtuin 1 were lower in dexamethasone-treated cells compared with controls. Knockdown of p53 or inhibition of p53 activity prevented dexamethasone-induced senescence. Activation of sirtuin 1 either by exogenous overexpression or by treatment with resveratrol or low glucose prevented dexamethasone-induced senescence. Immunohistochemical analysis of tendon biopsies taken before and after glucocorticoid injection revealed a significant increase in the percentage of p53-positive cells (p=0.03). The percentage of p21-positive cells also tended to be higher post-injection (p=0.06) suggesting glucocorticoids activate the p53/p21 senescence-inducing pathway in vivo as well as in vitro.

CONCLUSION

As cell senescence is irreversible in vivo, glucocorticoid-induced senescence may result in long-term degenerative changes in tendon tissue.

Efficacy of platelet-rich plasma for chronic tennis elbow: a double-blind, prospective, multicenter, randomized controlled trial of 230 patients

BACKGROUND

Elbow tenderness and pain with resisted wrist extension are common manifestations of lateral epicondylar tendinopathy, also known as tennis elbow. Previous studies have suggested platelet-rich plasma (PRP) to be a safe and effective therapy for tennis elbow.

PURPOSE

To evaluate the clinical value of tendon needling with PRP in patients with chronic tennis elbow compared with an active control group.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 2.

METHODS

A total of 230 patients with chronic lateral epicondylar tendinopathy were treated at 12 centers over 5 years. All patients had at least 3 months of symptoms and had failed conventional therapy. There were no differences in patients randomized to receive PRP (n = 116) or active controls (n = 114). The PRP was prepared from venous whole blood at the point of care and contained both concentrated platelets and leukocytes. After receiving a local anesthetic, all patients had their extensor tendons needled with or without PRP. Patients and investigators remained blinded to the treatment group throughout the study. A successful outcome was defined as 25% or greater improvement on the visual analog scale for pain.

RESULTS

Patient outcomes were followed for up to 24 weeks. At 12 weeks (n = 192), the PRP-treated patients reported an improvement of 55.1% in their pain scores compared with 47.4% in the active control group (P = .163). At 24 weeks (n = 119), the PRP-treated patients reported an improvement of 71.5% in their pain scores compared with 56.1% in the control group (P = .019). The percentage of patients reporting significant elbow tenderness at 12 weeks was 37.4% in the PRP group versus 48.4% in the control group (P = .143). Success rates for patients at 12 weeks were 75.2% in the PRP group versus 65.9% in the control group (P = .104). At 24 weeks, 29.1% of the PRP-treated patients reported significant elbow tenderness versus 54.0% in the control group (P = .009). Success rates for patients with 24 weeks of follow-up were 83.9% in the PRP group compared with 68.3% in the control group (P = .037). No significant complications occurred in either group.

CONCLUSION

No significant differences were found at 12 weeks in this study. At 24 weeks, however, clinically meaningful improvements were found in patients treated with leukocyte-enriched PRP compared with an active control group.

Healing of subcutaneous tendons: Influence of the mechanical environment at the suture line on the healing process

Tendon ruptures remain a significant musculoskeletal injury. Despite advances in surgical techniques and procedures, traditional repair techniques maintain a high incidence of rerupture or tendon elongation. Mechanical loading and biochemical signaling both control tissue healing. This has led some researchers to consider using a technique based on tension regulation at the suture line for obtaining good healing. However, it is unknown how they interact and to what extent mechanics control biochemistry. This review will open the way for understanding the interplay between mechanical loading and the process of tendon healing.