Comparison Between Steroid and 2 Different Sites of Botulinum Toxin Injection in the Treatment of Lateral Epicondylalgia: A Randomized, Double-Blind, Active Drug-Controlled Pilot Study

Botulinum toxin in the rehabilitation of painful syndromes: multiperspective literature analysis, lexical analysis and systematic review of randomized controlled trials

Pain represents a common symptom of several diseases and is often associated with a reduction in rehabilitation outcomes and recovery. The effectiveness of pain alleviation by botulinum toxin has been recently demonstrated. We searched in PubMed the papers about this topic published in the last ten years, and we selected clinical trials, guidelines, meta-analyses, reviews, and systematic reviews. We used different approaches: multiperspective presentation, lexical evaluation, and systematic review. The systematic review was only performed for the randomized controlled trials. We predominantly found reviews and trials about the rehabilitation of stroke/brain injury and epicondylitis. The most common outcome measures were pain, function, and spasticity. Among the common words, pain was the most frequent and the terms were grouped into different families, especially concerning the outcomes. Rehabilitation showed a relatively low frequency. Finally, the systematic review showed moderate-low levels of bias which confirms the effectiveness of botulinum toxin for pain treatment. The current literature about botulinum toxin is wide and globally diffuse but with some limitations in study strategies and clearness in the formal presentation. The evidence justifies the use of botulinum toxin in treating pain in different diseases.

Botulinum Toxin in Chronic Lateral Epicondylitis, from Tendon to Muscle Approach-A Review

BACKGROUND

Chronic lateral epicondylitis challenges the therapeutical approach; underlying mechanisms are incompletely understood; neuropathic pain and central and peripheral sensitization may explain the fact that botulinum toxin has been found to play a role in pain and function management.

METHODS

We searched the literature for MeSH terms: lateral epicondylitis or synonyms and botulinum toxin.

RESULTS

We found 14 papers containing trials on botulinum toxin injection into the tendon or into the extensor muscles (specifically, extensor carpi radialis brevis and extensor communis digitorum). We followed the administration pathways, doses, timing, and side effects.

CONCLUSIONS

With a chronic course, the focus of the therapy shifts from the afflicted tendon to the inserting muscles, as muscle contracture may create a vicious loop to perpetuate and aggravate the disease. Doses, timing, and side effects are discussed.

Clinical efficacy of botulinum toxin in lateral elbow tendinopathy: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Botulinum toxin injections for lateral elbow tendinopathy have been used as an alternative therapeutic option. However, few studies have quantitatively summarized the effect of botulinum toxin as well as its clinical significance. We aimed to evaluate the clinical efficacy (based on pain and grip strength) and adverse events of botulinum toxin on lateral elbow tendinopathy.

PATIENTS AND METHODS

The MEDLINE, EMBASE, Web of Science, and Scopus databases were searched until March 2023 for randomized controlled trials reporting the effects of botulinum toxin injections on lateral elbow tendinopathy. A random- or fixed-effects model (depending of inter-study variability) and generic inverse variance method were used to pool quantitative data from outcomes. The risk of bias was assessed with the Cochrane Risk of Bias 2.0 tool.

RESULTS

A total of 8 clinical trials recruiting 438 subjects were included for meta-analysis. Pooled analysis revealed that botulinum toxin significantly reduced pain (mean difference [MD] -0.95, 95% CI [-1.63, -0.26], p=0.007) but it was not clinically relevant. No significant effect was detected for grip strength (MD-0.62kg, 95% CI [-2.25, 1.02], p=0.46) or in the risk for adverse events (odds ratio [OR] 0.41, 95% CI [0.05, 3.56], p=0.42) between botulinum toxin injection and control interventions.

DISCUSSION

The use of botulinum toxin reached greater pain relief than control interventions and normal saline after a period of 12 to 24 weeks. However, changes in pain relief did not reach clinical significance. The studies that had the greatest reduction in pain used higher doses of botulinum toxin (60 U). Additionally, differences in grip strength and adverse events did not reach statistical or clinical importance. A subanalysis indicated that botulinum toxin outperformed corticosteroid injections in terms of improving grip strength. Botulinum toxin only causes local and minimal side effects such as irritation, ecchymosis, and paralysis.

LEVEL OF EVIDENCE

I.

Effectiveness of different doses of botulinum neurotoxin in lateral epicondylalgia: A network meta-analysis

BACKGROUND

Previous studies have investigated the role of botulinum neurotoxin (BoNT) in lateral epicondylalgia, with controversial results. We hypothesized that BoNT would be effective and safe for the treatment of lateral epicondylalgia.

OBJECTIVE

To investigate the effectiveness and safety of different doses of BoNT in participants with lateral epicondylalgia.

METHODS

PubMed, Embase, and Cochrane Library were searched up to August 27, 2022, for randomized controlled trials (RCTs) of BoNT treatment for epicondylalgia. The Cochrane risk of bias tool was used for quality assessment. A network meta-analysis and a trial sequential analysis (TSA) were conducted on pain, grip strength and adverse events. Meta-regression was applied for high heterogeneity comparisons.

RESULTS

We included 8 RCTs consisting of 448 participants. Four studies scored low risk of bias in all categories, whereas the other 4 studies had unclear risk only in the selection bias category. The network meta-analysis and TSA revealed that corticosteroid (standardized mean difference [SMD]: -1.32, 95% CI: -2.13; -0.50), high-dose BoNT (SMD -1.32, -2.04; -0.61), and low-dose BoNT (SMD -0.52, -0.93; -0.10), relieved pain significantly better than placebo for up to 7 to 10 weeks. High-dose BoNT demonstrated a significantly greater reduction in pain than low-dose BoNT for up to 7 to 10 weeks (SMD -0.81, -1.39; -0.22). Finally, after low-dose BoNT, younger participants (p = 0.023) and women (p = 0.012) showed more pain decrease than older individuals and men at 2 to 6 weeks. As for grip strength and adverse events, only grip strength after low-dose BoNT versus placebo (SMD -0.49, -0.88; -0.10) and corticosteroid (SMD -1.36, -2.15; -0.57) at 2 to 6 weeks reached significance after threshold adjustment in TSA.

CONCLUSIONS

Our meta-analysis confirmed the effectiveness of low-dose BoNT in the reduction of pain for lateral epicondylalgia. Further conclusions cannot be drawn due to insufficient available data.

Extracorporeal Shock Wave Therapy Shows Superiority Over Injections for Pain Relief and Grip Strength Recovery in Lateral Epicondylitis: A Systematic Review and Network Meta-analysis

PURPOSE

To examine the efficacy of extracorporeal shock wave therapy (ESWT) and injection therapies by synthesizing direct and indirect evidence for all pairs of competing therapies for lateral epicondylitis.

METHODS

PubMed, EMBASE, and Web of Science databases were searched for all appropriate randomized controlled trials (RCTs), assessing the effect of ESWT or injection therapies. The primary outcome was short-term (≤3 months) and medium-term (>3 months but ≤12 months) pain, while the secondary outcomes were grip strength and patient-reported outcome measures. All outcomes were assessed using standardized mean differences (SMDs) with 95% confidence intervals (CIs) and were ranked using surface under the cumulative ranking curve (SUCRA) probabilities to determine a hierarchy of treatments. Sensitivity analysis was performed to eliminate potential therapeutic effects of normal saline (NS) and exclude trials that included patients with acute lateral epicondylitis (LE).

RESULTS

40 RCTs were included to evaluate ESWT and five different injection therapies, including corticosteroids (CSs), autologous whole blood, platelet-rich plasma (PRP), botulinum toxin A (BoNT-A), and dextrose prolotherapy (DPT). DPT (-.78 [-1.34 to -.21]), ESWT (.57 [-.89 to -.25]), PRP (-.48 [-.85 to -.11]), and BoNT-A (-.43 [-.84 to -.02]) outperformed placebo for short-term pain relief; ESWT (-.44 [-.85 to -.04]) outperformed placebo for medium-term pain relief. DPT was ranked as the most optimal short-term and medium-term pain reliever (SUCRA, 87.3% and 98.6%, respectively). ESWT was ranked as the most optimal short-term and medium-term grip strength recovery (SUCRA; 79.4% and 86.4%, respectively).

CONCLUSIONS

DPT and ESWT were the best two treatment options for pain control and ESWT was the best treatment option for grip strength recovery. CSs were not recommended for the treatment of LE. More evidence is required to confirm the superiority in pain control of DPT among all these treatment options on LE.

LEVEL OF EVIDENCE

Level I, meta-analysis of Level I randomized controlled trials.

Are there any changes in strength after the application of Kinesio taping in lateral epicondylalgia?

BACKGROUND

In 1973, Dr. Kenzo Kase developed Kinesio taping from the hypothesis that this external component could aid the functions of muscles and other tissues. There are different studies on this issue, but none has completely clarified the research question.

OBJECTIVE

To study the application of Kinesio taping in the variation of isometric muscle strength of the hand extension and grip, isokinetic strength of the pronation and supination movements, and the time it takes to reach that strength in patients with lateral epicondylalgia.

METHODS

An analytical, experimental, randomized study was carried out with 104 subjects with lateral epicondylalgia. The subjects were randomly distributed among two groups: one received Kinesio taping and the other a placebo material. A pre- and post-intervention measurement was performed. The post-measurement was carried out 24 hours later so as to completely eliminate the fatigue effect produced by the first day measurements, as well as to ensure that the intervention was effective, and not immediate. The measurements were made using a dynamometer.

RESULTS

No significant differences were found between the application of Kinesio taping and placebo material in subjects with lateral epicondylalgia regarding the variation of muscle strength in any of the study variables (p> 0.05 for all studied variables).

CONCLUSIONS

Kinesio taping produces no change in strength after application and exerts an effect similar to that of a placebo.

A Comparative Study on Short-Term Effects of Compression Orthosis and Exercises in the Treatment of Pectus Carinatum: A Randomized Controlled Pilot Feasibility Trial

INTRODUCTION

 Pectus carinatum (PC) is a congenital chest wall deformity which is characterized by the protrusion of the sternum and costal cartilages. Although orthotic and exercise therapies are commonly offered by physicians for PC treatment, there is a lack of evidence on the benefits of exercises and how long the orthosis should be worn. The aim of this study is to investigate the effects and feasibility of custom-made compression orthosis and exercises in the treatment of PC.

MATERIALS AND METHODS

 Patients with PC aged 7 to 17 years old were randomized into three groups: compression orthosis 23 hours, compression orthosis 8 hours, and control group. All groups received exercises for 1 hour a day for 3 weeks. Additionally, compression orthosis 23 hours group wore the orthosis for 23 hours a day, while compression orthosis 8 hours group wore the orthosis for 8 hours a day. PC protrusion, pressure of correction, thorax lateral and anteroposterior parameters, external chest wall measurements, and Nuss Questionnaire were evaluated before and after the treatment. Also, adverse effects, retention, and compliance were assessed. Feasibility was evaluated by calculating the percentages of recruitment, retention, and safety.

RESULTS

 The compression orthosis 23 hours group showed greater improvements than the other groups. After treatment, all groups showed significant changes in protrusion, pressure of correction, and external chest wall measurements. Adverse events occurred with similar frequency across groups. Retention percentages did not differ among groups.

CONCLUSION

 Compression orthosis use for 23 hours can be recommended rather than its use for 8 hours because 23 hours of orthosis use has better correction and similar adverse effects.

Efficacy of Botulinum Toxin in Treating Lateral Epicondylitis-Does Injection Location Matter?: A Systematic Review

OBJECTIVE

Clinical trials assessing the efficacy of botulinum toxin in treating recalcitrant lateral epicondylitis have demonstrated varied results and differed greatly in methodology. The objective of this systematic review was to demonstrate injection location as a significant contributor to outcome heterogeneity.

DESIGN

Two reviewers independently conducted a systematic review using Scopus, Embase, and PubMed for randomized controlled trials assessing botulinum toxin in the treatment of lateral epicondylitis. After applying inclusion/exclusion criteria to abstracts and reviewing the full-text articles, seven studies were found representing six separate injection locations. Reduction in visual analog scale pain and change in grip strength were the principal outcomes of interest.

RESULTS

The largest reduction in pain was seen in injection at 1/3 of the length of the forearm from the lateral epicondyle at 16-wk follow-up, whereas the smallest reduction was seen at 12-wk follow-up after injection at the 0-cm mark. Differences were also identified in grip strength, although all studies reported return to baseline strength by weeks 12-18.

CONCLUSIONS

This study demonstrates injection location as a potential source of heterogeneity. This clinical question warrants further evaluation with direct comparison of outcomes at different injection locations while controlling for dosage, toxin type, and ultrasound/electromyographic guidance.

The Effect of Botulinum Toxin Injection into the Common Extensor Tendon in Patients with Chronic Lateral Epicondylitis: A Randomized Trial

BACKGROUND

Botulinum toxin (BTX) is widely used for pain control in various musculoskeletal disorders.

OBJECTIVES

We evaluated the analgesic effect of botulinum toxin type A (BTX-A) in chronic lateral epicondylitis and compared the effect between 10 and 50 IU of BTX-A.

METHODS

Sixty subjects with chronic lateral epicondylitis were included and underwent a BTX-A injection in the common extensor tendon. The subjects were randomly allocated into two groups: the small-dose group (SD group; 30 subjects, 10 IU) and large-dose group (LD group; 30 subjects, 50 IU). Treatment outcomes were evaluated by measuring the pain level using the numeric rating scale (NRS) and measuring grip strength before and one, two, three, four, five, and six months after treatment.

RESULTS

Subjects in both groups showed a significant decrease in NRS scores at all evaluation time points after treatment. The reduction in NRS scores was significantly greater in the LD group at one, two, three, and four months after treatment. Six months after treatment, 19 subjects (63.3%) in the SD group and 21 (70%) in the LD group reported successful pain relief (pain relief ≥50%). The rate of successful pain relief was not significantly different between the two groups. Grip strength was more increased in the LD group at one, two, three, four, and six months after treatment.

CONCLUSIONS

BTX-A injection into the common extensor tendon can be a good treatment option for chronic lateral epicondylitis. The 50-IU BTX-A injection achieved a better outcome than the 10-IU injection.

Minimally invasive treatment of lateral epicondylitis

Lateral epicondylitis (LE), also known as tennis elbow, is the most common cause of elbow pain in adults, with approximately 1-3% of the general population being afflicted. Although the condition is usually self-limiting, pain can be a major hindrance, limiting daily activity and the work capacity of patients. As a result, many treatment options have become available with the aim to shorten the duration of the disease and increase the quality of life. Steroid injections, NSAIDs, topical creams, platelet-rich plasma, physical therapy, and kinesiotaping are considered conservative treatments, while surgical options are last-resort treatments reserved for refractory LE. In this review, we will provide a brief summary of LE and focus on addressing conservative and minimally invasive interventional options for the treatment of LE.

Botulinum Toxin for Chronic Lateral Epicondylitis (LE)

Lateral epicondylitis is a common disease in orthopaedic practice. Although the majority of cases do not become chronic, patients who do not respond to the initial treatment may suffer from pain in the long term and effective treatment is challenging. The off-label use of botulinum toxin is one of the common potential indications for the substance in orthopaedics and traumatology. In a literature review of 2000 - 2019, eight EBM ≥ level 3 studies evaluating the use of botulinum toxin in lateral epicondylitis were found. Five of these studies evaluated botulinum toxin versus placebo in chronic cases; two other studies compared botulinum toxin with corticosteroids in acute cases and classic Hohmann surgery in chronic cases; the eighth study compared botulinum toxin in two different injection sites and corticosteroids by classic injection. Our findings suggest that the use of this substance may be a treatment option in refractory chronic cases before surgery is indicated. The working group on botulinum toxin in O & T of the International Musculoskeletal Pain Society (IMPS/IGOST) introduced an alternative injection schedule, which combines findings from the recent clinical literature with practical experience in order to reduce the risk of side effects while ensuring treatment effectiveness. Using 2 simple tests of function and, if necessary, sonographic verification, 2 separate injection sites in the extensor carpi radialis or the extensor digitorum can be identified by palpation. The tendon level on the lateral epicondyle acts as the third injection site. With optimal use of the ampoule content, the 3 injection sites can be infiltrated individually, depending on the muscle status. On the one hand, this enables treatment to take place after a dual therapy approach and, on the other hand, the risk of overdose in a muscle with subsequent unnecessary muscle weakening can be reduced.

Current Trends for Treating Lateral Epicondylitis

Lateral epicondylitis, also known as 'tennis elbow', is a degenerative rather than inflammatory tendinopathy, causing chronic recalcitrant pain in elbow joints. Although most patients with lateral epicondylitis resolve spontaneously or with standard conservative management, few refractory lateral epicondylitis are candidates for alternative non-operative and operative modalities. Other than standard conservative treatments including rest, analgesics, non-steroidal anti-inflammatory medications, orthosis and physical therapies, nonoperative treatments encompass interventional therapies include different types of injections, such as corticosteroid, lidocaine, autologous blood, platelet-rich plasma, and botulinum toxin, which are available for both short-term and long-term outcomes in pain resolution and functional improvement. In addition, newly emerging biologic enhancement products such as bone marrow aspirate concentrate and autologous tenocyte injectates are also under clinical use and investigations. Despite all non-operative therapeutic trials, persistent debilitating pain in patients with lateral epicondylitis for more than 6 months are candidates for surgical treatment, which include open, percutaneous, and arthroscopic approaches. This review addresses the current updates on emerging non-operative injection therapies as well as arthroscopic intervention in lateral epicondylitis.

Comparative effectiveness of botulinum toxin versus non-surgical treatments for treating lateral epicondylitis: a systematic review and meta-analysis

Objectives:

To explore the effectiveness of botulinum toxin compared with non-surgical treatments in patients with lateral epicondylitis.

Methods:

Data sources including PubMed, Scopus, Embase and Airity Library from the earliest record to February 2017 were searched. Study design, patients’ characteristics, dosage/brand of botulinum toxin, injection techniques, and measurements of pain and hand grip strength were retrieved. The standardized mean differences (SMDs) in pain relief and grip strength reduction were calculated at the following time points: 2-4, 8-12, and 16 weeks or more after injection.

Results:

Six randomized controlled trials (321 participants) comparing botulinum toxin with placebo or corticosteroid injections were included. Compared with placebo, botulinum toxin injection significantly reduced pain at all three time points (SMD, -0.729, 95% confidence interval [CI], -1.286 to -0.171; SMD, -0.446, 95% CI, -0.740 to -0.152; SMD, -0.543, 95% CI, -0.978 to -0.107, respectively). Botulinum toxin was less effective than corticosteroid at 2-4 weeks (SMD, 1.153; 95% CI, 0.568-1.737) and both treatments appeared similar in efficacy after 8 weeks. Different injection sites and dosage/brand did not affect effectiveness. Botulinum toxin decreased grip strength 2-4 weeks after injection, and high equivalent dose could extend its paralytic effects to 8-12 weeks.

Conclusions:

When treating lateral epicondylitis, botulinum toxin was superior to placebo and could last for 16 weeks. Corticosteroid and botulinum toxin injections were largely equivalent, except the corticosteroid injections were better at pain relief in the early stages and were associated with less weakness in grip in the first 12 weeks.