Long-term beneficial effects of platelet-rich plasma for non-insertional Achilles tendinopathy

Surgical Management of Non-insertional Achilles Tendinopathy

Non-insertional Achilles tendinopathy is a common condition among aging athletes participating in high-impact activities. The authors have summarized the typical presentation and objectives in surgical management and have provided a proposed surgical treatment algorithm for the successful management of non-insertional Achilles tendinopathy.

Advancements in Therapeutic Approaches for Degenerative Tendinopathy: Evaluating Efficacy and Challenges

Degenerative tendinopathy results from the accumulation of minor injuries following unsuccessful tendon repair during acute tendon injuries. The process of tendon repair is prolonged and varies between individuals, making it susceptible to reinjury. Moreover, treating chronic tendinopathy often requires expensive and extensive rehabilitation, along with a variety of combined therapies to facilitate recovery. This condition significantly affects the quality of life of affected individuals, underscoring the urgent need for more efficient and cost-effective treatment options. Although traditional treatments have improved significantly and are being used as substitutes for surgical interventions, the findings have been inconsistent and conflicting. This review aims to clarify these issues by exploring the strengths and limitations of current treatments as well as recent innovations in managing various forms of degenerative tendinopathy.

Challenges and opportunities of medicines for treating tendon inflammation and fibrosis: A comprehensive and mechanistic review

BACKGROUND

Tendinopathy refers to conditions characterized by collagen degeneration within tendon tissue, accompanied by the proliferation of capillaries and arteries, resulting in reduced mechanical function, pain, and swelling. While inflammation in tendinopathy can play a role in preventing infection, uncontrolled inflammation can hinder tissue regeneration and lead to fibrosis and impaired movement.

OBJECTIVES

The inability to regulate inflammation poses a significant limitation in tendinopathy treatment. Therefore, an ideal treatment strategy should involve modulation of the inflammatory process while promoting tissue regeneration.

METHODS

The current review article was prepared by searching PubMed, Scopus, Web of Science, and Google Scholar databases. Several treatment approaches based on biomaterials have been developed.

RESULTS

This review examines various treatment methods utilizing small molecules, biological compounds, herbal medicine-inspired approaches, immunotherapy, gene therapy, cell-based therapy, tissue engineering, nanotechnology, and phototherapy.

CONCLUSION

These treatments work through mechanisms of action involving signaling pathways such as transforming growth factor-beta (TGF-β), mitogen-activated protein kinases (MAPKs), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), all of which contribute to the repair of injured tendons.

Platelet-rich plasma injections as a treatment for Achilles tendinopathy and plantar fasciitis in athletes

Platelet-rich plasma (PRP) injections represent a growing interest in the use of biologic therapies for treatment of musculoskeletal injuries. One possible application of PRP is in the management of overuse injuries commonly experienced by athletes. The aim of this review is to evaluate and summarize existing evidence regarding the efficacy of PRP in the treatment of Achilles tendinopathy and plantar fasciitis in athletes. Although many lower quality single-armed studies have demonstrated clinical improvement in athletes treated for Achilles tendinopathy with PRP, higher quality randomized controlled trials (RCTs) have shown no clear benefit in athletes. Existing data suggest PRP significantly improves clinical outcomes for plantar fasciitis in the general population, but very few studies and no RCTs are available that specifically analyze outcomes in athletic populations. More research is needed to evaluate how platelet concentration, leukocyte and erythrocyte presence, and sport type may interact to affect clinical outcomes in athletes.

ICON 2020-International Scientific Tendinopathy Symposium Consensus: A Systematic Review of Outcome Measures Reported in Clinical Trials of Achilles Tendinopathy

BACKGROUND

Nine core domains for tendinopathy have been identified. For Achilles tendinopathy there is large variation in outcome measures used, and how these fit into the core domains has not been investigated.

OBJECTIVE

To identify all available outcome measures outcome measures used to assess the clinical phenotype of Achilles tendinopathy in prospective studies and to map the outcomes measures into predefined health-related core domains.

DESIGN

Systematic review.

DATA SOURCES

Embase, MEDLINE (Ovid), Web of Science, CINAHL, The Cochrane Library, SPORTDiscus and Google Scholar.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Clinical diagnosis of Achilles tendinopathy, sample size ≥ ten participants, age ≥ 16 years, and the study design was a randomized or non-randomized clinical trial, observational cohort, single-arm intervention, or case series.

RESULTS

9376 studies were initially screened and 307 studies were finally included, totaling 13,248 participants. There were 233 (177 core domain) different outcome measures identified across all domains. For each core domain outcome measures were identified, with a range between 8 and 35 unique outcome measures utilized for each domain. The proportion of studies that included outcomes for predefined core domains ranged from 4% for the psychological factors domain to 72% for the disability domain.

CONCLUSION

233 unique outcome measures for Achilles tendinopathy were identified. Most frequently, outcome measures were used within the disability domain. Outcome measures assessing psychological factors were scarcely used. The next step in developing a core outcome set for Achilles tendinopathy is to engage patients, clinicians and researchers to reach consensus on key outcomes measures.

PROSPERO REGISTRATION

CRD42020156763.

To evaluate the outcomes of PRP treatment in Achilles tendinopathy: An intriguing methodological problem

INTRODUCTION

Assessing the outcomes of Platelet Rich Plasma (PRP) treatment in Achilles Tendinopathy (AT) may prove difficult due to several methodological reasons. For example, given that the simple mean of VISA-A score is just the result of positive, negative or null values, this may provide incomplete information, and therefore the size of individual changes can remain unknown. On the contrary, calculating the score changes in each subject after treatment would allow a more appropriate evaluation of the clinical results. However, this method has been applied only to few small-scale studies. Therefore we performed a retrospective study aiming to determine: (1) are the percentages of positive outcomes of the present research comparable to those of previous studies performed in different settings? (2) Is there a relationship between the size of increase of the clinical score and the patient satisfaction?

HYPOTHESES

The percentages of positive outcomes of the present research are comparable to those of previous studies performed in different settings.

MATERIAL AND METHODS

This is a retrospective observational study. Eighty-four patients submitted to PRP treatment for mid-portion AT were enrolled. Pain and function were evaluated by means of VISA-A scale. Besides the mean, in each subject the pre- and post-treatment difference of VISA-A score was computed and the outcome was defined clinically no detectable, detectable and evident according to the increasing values of the score (0 to 9 points, 10 to 19, and≥20 points change, respectively). The Likert's scale for the patients satisfaction was also used.

RESULTS

The mean VISA-A increased significantly after treatment (from 50.1±9.1 at baseline to 63.7±13.8 at 3 months (p=0.00001) and 67.2±14.1 at 6 months (p=0.00001)). At 3 and 6 months the subjects belonging to the prefixed categories were 15, 45, 24 and 19, 36, 29, respectively. Moreover, large discrepancies were observed between the size of increase of the clinical score and patients satisfaction, mainly for intermediate increases of the score.

DISCUSSION

The percentages of positive outcomes found in this study are slightly lower than those reported in literature. The different patients expectations about the efficacy of the therapy can explain the discrepancies between the size of increase of the clinical score and the individual satisfaction. In comparison to the simple mean, the individual changes of VISA-A score allow a proper evaluation of the outcomes. The research shows that discrepancies can be present in the percentage of positive clinical outcomes between different studies. The size of increase of the clinical score does not always match patient satisfaction.

LEVEL OF PROOF

IV retrospective study without control group.

Meta-analysis of Noninsertional Achilles Tendinopathy

BACKGROUND

Achilles tendinopathy is a common clinical problem that can be either insertional or noninsertional. A variety of treatment methods have been described, although little consensus exists on an optimal method or methods. We sought to investigate the current evidence on different treatment methods for noninsertional Achilles tendinopathy, with a focus on functional outcomes.

METHODS

We performed a review of the available literature in PubMed and the Cochrane Central Register of Controlled Trials. Data from included studies were categorized according to treatment method and analyzed with respect to functional outcome and complication rate.

RESULTS

In total, 1420 abstracts were reviewed, of which 72 articles containing 3523 patients met inclusion criteria. Within the 72 studies included, 6 operative techniques and 19 nonoperative treatments were evaluated.

CONCLUSION

A wide variety of treatments are available for noninsertional Achilles tendinopathy, although newer treatments and most operative methods lack high-level evidence. Eccentric exercise is the most thoroughly studied and supported nonoperative treatment, while tenotomy and debridement is the operative procedure with the most evidence of efficacy. Platelet-rich plasma injections and extracorporeal shockwave therapy have proven to be viable second-line nonoperative treatments. Gastrocnemius recession and flexor hallucis longus transfer have shown benefit in case series.

LEVEL OF EVIDENCE

Level II, systematic review.

Post-Procedure Protocols Following Platelet-Rich Plasma Injections for Tendinopathy: A Systematic Review

OBJECTIVE

Platelet-rich plasma (PRP) has been increasingly studied as a treatment for tendinopathy. Many factors may influence outcomes after PRP, including different protocols following administration. It was hypothesized that there would be heterogeneity in post-PRP protocols.

LITERATURE SURVEY

A systematized review of the literature on post-PRP protocols for tendinopathy was conducted using an electronic search of MEDLINE and Embase databases through September 2018.

METHODOLOGY

After duplicates were removed, English language articles involving adult patients who received PRP for tendinopathy were reviewed. Exclusion criteria included studies with fewer than 10 patients, PRP used to treat pathology other than tendinopathy, multiple protocols in one study, and surgical settings. Protocol specifics were extracted including nonsteroidal anti-inflammatory drugs (NSAID) restrictions before and after injection, postinjection restrictions on movement and weight bearing, use of orthoses, activity modifications, and postinjection rehabilitation protocols. Given limitations in the data, a meta-analysis was not performed.

SYNTHESIS

Eighty-four studies met inclusion criteria. Following PRP injection, weight-bearing restrictions were mentioned rarely (12% of protocols). Orthosis use was uncommon overall (18%) but more common in Achilles tendinopathy protocols (53%). The majority of protocols instituted a period of stretching (51%) and strengthening (54%). Stretching programs generally began 2-7 days following injection, and strengthening programs began within 2-3 weeks. Preinjection NSAID restriction was reported rarely (20%), whereas postinjection NSAID restriction was more common (56%), with a typical restriction of greater than 2 weeks (38%). Return to play or full activity was reported in 42% of protocols, most commonly at 4-6 weeks following injection.

CONCLUSION

Although the clinical effectiveness of PRP remains controversial, even less is known about the effect of post-PRP protocols, which may affect the outcomes attributed to PRP itself. No studies directly compare post-PRP protocols, and the protocols studied demonstrate substantial heterogeneity. Some consensus regarding post-PRP protocols exists, although the rationale for these recommendations is limited.

Factors associated with positive outcomes of platelet-rich plasma therapy in Achilles tendinopathy

BACKGROUND

The efficacy of platelet-rich plasma in the treatment for Achilles tendinopathy is debated. Therefore, it is important to know which factors, related to the subjects and/or the disease, are associated with positive or negative outcomes. Aim of this study was to evaluate in a large cohort of patients with Achilles mid-portion tendinopathy which variables were independently associated with a positive outcome after platelet-rich plasma treatment.

MATERIAL AND METHODS

Eighty-four subjects with Achilles tendinopathy were evaluated by means of VISA-A score and ultrasound and treated with a single platelet-rich plasma injection once a week for 3 weeks. Afterward, a rehabilitation program, based on eccentric training, was implemented. At 3 and 6 months, the relationship between the mean VISA-A score and the following putative predictors was evaluated: sex, age, physical activity, sport, smoking, metabolic risk factors, BMI, symptoms duration, tendon damage, neovessels, adherence to eccentric training. Finally, the percentage of clinically evident positive outcomes (defined as an increase in VISA-A score ≥ 20 points) related to each variable was computed.

RESULTS

At final follow-up, using the General Linear Model for Repeated Measures procedure, male sex (0.02), age ≤ 40 (0.05) and adequate eccentric training (0.02) were found to be independently associated with a significant increase in the mean VISA-A score. Moreover, the clinically evident positive outcomes, as previously defined, were significantly associated with male sex (0.01), age ≤ 40 (0.000), BMI ≤ 25 (0.001), symptoms duration ≤ 12 months (0.02) and good adherence to eccentric training (0.004).

CONCLUSION

Younger age, male sex and good adherence to eccentric training can be considered predictors of better results after platelet-rich plasma therapy in Achilles tendinopathy.

Platelet Concentrates in Musculoskeletal Medicine

Platelet concentrates (PCs), mostly represented by platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) are autologous biological blood-derived products that may combine plasma/platelet-derived bioactive components, together with fibrin-forming protein able to create a natural three-dimensional scaffold. These types of products are safely used in clinical applications due to the autologous-derived source and the minimally invasive application procedure. In this narrative review, we focus on three main topics concerning the use of platelet concentrate for treating musculoskeletal conditions: (a) the different procedures to prepare PCs, (b) the composition of PCs that is related to the type of methodological procedure adopted and (c) the clinical application in musculoskeletal medicine, efficacy and main limits of the different studies.

Conservative Treatment of Chronic Achilles Tendinopathy: A Systematic Review

Achilles tendinopathy is a common musculoskeletal disorder. Athletes, runners and jumpers, and the sedentary are frequently affected. Numerous are the therapeutic choices to manage these kinds of disorders. The aim of this review is to analyze the available literature to document the up-to-date evidence on conservative management of Achilles tendinopathy. A systematic review of two medical electronic databases was performed by three independent authors, using the following inclusion criteria: conservative treatment consisted of pharmacologic, physical therapy without operative treatment, with more of 6 months symptoms and a minimum average of 6-months follow-up. Studies of any level of evidence, reporting clinical results, and dealing with Achilles tendinopathy and conservative treatment were searched for. A total of n = 1228 articles were found. At the end of the first screening, following the previously described selection criteria, we selected n = 94 articles eligible for full-text reading. Ultimately, after full-text reading and a reference list check, we selected n = 29 articles. Achilles tendinopathy is a frequent musculoskeletal disorder and several conservative treatments have been proposed, but no therapy is universally accepted, except for eccentric exercise training, which is the gold standard and a commonly used protocol.

Platelet-rich plasma in the foot and ankle

PURPOSE OF REVIEW

Platelet-rich plasma has become an increasingly popular treatment option within the orthopedic community to biologically enhance and stimulate difficult-to-heal musculoskeletal tissues. This review evaluates the recent literature on platelet-rich plasma use in the treatment of foot and ankle pathologies.

RECENT FINDINGS

Recent literature has demonstrated platelet-rich plasma to have a possible benefit in the treatment of Achilles pathology, chronic plantar fasciitis, osteochondral lesions of the talus, ankle osteoarthritis, and diabetic foot ulcers. However, given the lack of standardization of platelet-rich plasma preparations and protocols and the predominance of low-quality studies, no definitive treatment indications exist. Platelet-rich plasma is a promising treatment option, but at present, there is only limited clinical evidence supporting its use in foot and ankle applications.

Platelet-rich plasma in tendon-related disorders: results and indications

PURPOSE

Platelet-rich plasma (PRP) is currently the most exploited strategy in the clinical practice to provide a regenerative stimulus for tendon healing. The aim of the present study was to systematically review the available evidence on the treatment of the main tendon disorders where PRP is currently applied.

METHODS

A systematic review of the literature was performed on the use of PRP as a treatment for tendinopathies focusing on the following sites: Achilles tendon, patellar tendon, rotator cuff tendons, and lateral elbow tendons. The following inclusion criteria for relevant articles were used: clinical trials written in English language up to 21 June 2016 on the use of PRP in the conservative or surgical treatment of the aforementioned tendinopathies.

RESULTS

The research identified the following clinical trials dealing with the application of PRP in the selected tendons: 19 papers on patellar tendon (6 being RCTs: 4 dealing with PRP conservative application and 2 surgical), 24 papers on Achilles tendon (4 RCTs: 3 conservative and 1 surgical), 29 on lateral elbow tendons (17 RCTs, all conservative), and 32 on rotator cuff (22 RCTs: 18 surgical and 3 conservative).

CONCLUSION

Patellar tendons seem to benefit from PRP injections, whereas in the Achilles tendon, PRP application is not indicated neither as a conservative approach nor as a surgical augmentation. Lateral elbow tendinopathy showed an improvement in most of the high-level studies, but the lack of proven superiority with respect to the more simple whole-blood injections still questions its use in the clinical practice. With regard to rotator cuff pathology, the vast majority of surgical RCTs documented a lack of beneficial effects, whereas there is still inconclusive evidence concerning its conservative application in rotator cuff disorders.

LEVEL OF EVIDENCE

Systematic review of level I-IV trials, Level IV.

α2-Macroglobulin: Autologous Protease Inhibition Technology

α₂-Macroglobulin (A2M) is a plasma glycoprotein best known for its ability to inhibit a broad spectrum of serine, threonine, and metalloproteases as well as inflammatory cytokines by a unique bait-and-trap method. A2M has emerged as a unique potential treatment of cartilage-based pathology and inflammatory arthritides. This article describes the unique method by which A2M not only inhibits the associated inflammatory cascade but also disrupts the catabolic process of cartilage degeneration. Autologous concentrated A2M from plasma is currently in use to successfully treat various painful arthritides. Future directions will focus on recombinant variants that enhance its anti-inflammatory and disease-modifying potential.

ACR Appropriateness Criteria® Chronic Ankle Pain

Chronic ankle pain is a common clinical problem whose cause is often elucidated by imaging. The ACR Appropriateness Criteria for chronic ankle pain define best practices of image ordering. Clinical scenarios are followed by the imaging choices and their appropriateness. The information is in ordered tables with an accompanying narrative explanation to guide physicians to order the right test. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Optimization of pure platelet-rich plasma preparation: A comparative study of pure platelet-rich plasma obtained using different centrifugal conditions in a single-donor model

While it has been proved that centrifugal conditions for pure platelet-rich plasma (P-PRP) preparation influence the cellular composition of P-PRP obtained, the optimal centrifugal conditions to prepare P-PRP have not yet been identified. In the present study, platelet-containing plasma (PCP) was prepared with the first-spin of different double-spin methods and P-PRP was prepared with different double-spin methods. Whole-blood analysis was performed to evaluate the cellular composition of PCP and P-PRP. The basal and ADP-induced CD62P expression rates of platelets were assessed by flow cytometry to evaluate the function of platelets in PCP and P-PRP. Enzyme-linked immune sorbent assay was performed to quantify interleukin-1β, tumor necrosis factor-α, platelet-derived growth factor AB and transforming growth factor β1 concentrations of PCP and P-PRP. Correlations between the cellular characteristics and cytokine concentrations of P-PRP were analyzed by Pearson correlation analysis. Effects of P-PRP on the proliferation, survival and migration of human bone marrow-derived mesenchymal stem cells and human articular chondrocytes were evaluated by a Cell Counting Kit-8 assay, live/dead staining and Transwell assay, respectively. The results showed that centrifugation at 160 × g for 10 min and 250 × g for 15 min successively captured and concentrated platelets and growth factors significantly more efficiently with preservation of platelet function compared with other conditions (P<0.05). The correlation analysis showed that the similar leukocyte concentrations and leukocyte-reducing efficiencies resulted in similar pro-inflammatory cytokine concentrations in P-PRP (P>0.05) and the maximization of platelet concentration, platelet enrichment factor, platelet capture efficiency and platelet function resulted in the maximization of growth factor concentrations in P-PRP obtained using the optimal conditions (P<0.05). Compared with P-PRP obtained under other conditions, P-PRP obtained under the optimal conditions significantly promoted the proliferation and migration of cells (P<0.05) and did not alter cell survival (P>0.05). Therefore, centrifugation at 160 × g for 10 min and 250 × g for 15 min successively with removal of the buffy coat as a crucial step may provide an optimal preparation system of P-PRP for clinical application.

Midsubstance Tendinopathy, Percutaneous Techniques (Platelet-Rich Plasma, Extracorporeal Shock Wave Therapy, Prolotherapy, Radiofrequency Ablation)

The focus of this article is to present the current options available for noninvasive and percutaneous treatment options for noninsertional Achilles tendinopathy. An attempt is made to offer recommendations for both the treatment techniques as well as postprocedure protocols to be considered. Additionally, because there are numerous treatment options in this category, the different techniques are summarized in a chart format with a short list of pros and cons as well as the levels of evidence in the literature to support the different modalities.

Achilles Tendinopathy: Current Concepts about the Basic Science and Clinical Treatments

Achilles tendinopathy is one of the most frequently ankle and foot overuse injuries, which is a clinical syndrome characterized by the combination of pain, swelling, and impaired performance. The two main categories of Achilles tendinopathy are classified according to anatomical location and broadly include insertional and noninsertional tendinopathy. The etiology of Achilles tendinopathy is multifactorial including both intrinsic and extrinsic factors. Failed healing response and degenerative changes were found in the tendon. The failed healing response includes three different and continuous stages (reactive tendinopathy, tendon disrepair, and degenerative tendinopathy). The histological studies have demonstrated an increased number of tenocytes and concentration of glycosaminoglycans in the ground substance, disorganization and fragmentation of the collagen, and neovascularization. There are variable conservative and surgical treatment options for Achilles tendinopathy. However, there has not been a gold standard of these treatments because of the controversial clinical results between various studies. In the future, new level I researches will be needed to prove the effect of these treatment options.

Efficacy of autologous leukocyte-reduced platelet-rich plasma therapy for patellar tendinopathy in a rat treadmill model

BACKGROUND

An autologous platelet-rich plasma (PRP) therapy has currently been applied for the tendinopathy; however, its efficacy and an optimal platelets concentration in PRP were uncertain. We analyzed them in an animal model prepared using a repetitive running exercise.

METHODS

We made the tendinopathy rat model of patellar tendon using a rodent treadmill machine. Rats with tendinopathy were injected with leukocyte-reduced PRP at the platelets concentration of 1.0×10⁶/μL (P10 group), PRP at the platelets concentration of 5.0×10⁵/μL (P5 group) or normal saline (control group) into the space between the patellar tendon and the fat pad bilaterally or were multiply dry-needled at the tibial insertion site (MN group) at once. To assess the pain-reliving effect, the spontaneous locomotor activities at night (12 h) were measured every day. Histological sections of the patellar tendon stained with hematoxylineosin or prepared by TdT-mediated dUTP nick end labeling were microscopically analyzed.

RESULTS

The numbers of spontaneous locomotor activities in the P10 group were significantly larger than those in the P5, MN or control groups and they recovered up to a healthy level. On histologic examinations, the numbers of microtears, laminations, or apoptotic cells in the patellar tendons in the P10 or P5 groups were significantly lower than those in the MN or control groups, although no significant differences were observed between the P10 and P5 groups.

CONCLUSIONS

The injections of an autologous leukocyte-reduced PRP were effective for pain relief and for partial restoration of the patellar tendon in the tendinopathy rat model. The injections of a PRP at the platelets concentration of 1.0×10⁶/μL completely relieved the pain and were more effective than those at the platelets concentration of 5.0×10⁵/μL whereas there was no difference for the effect of histological restoration or apoptosis inhibition between them.