Clinically significant placebo analgesic response in a pilot trial of botulinum B in patients with hand pain and carpal tunnel syndrome

Effect of pronator teres muscle botulinum neurotoxin type-A injection on proximal median nerve entrapment

PURPOSE

We aimed to evaluate the effect of botulinum neurotoxin type-A (Btx-A) injection into the pronator teres muscle in proximal median nerve entrapment (PMNE).

METHODS

Intramuscular injection of 30 IU Btx-A into the pronator teres muscle was performed in 12 patients (14 extremities) diagnosed with PMNE. The injection was made under nerve stimulator control. One patient with thoracic outlet syndrome was excluded from the study and not included in the clinical evaluation. Grip and pinch strength, 2-point discrimination, Q-DASH score, and pain on VAS were evaluated and compared before and 6-8 months after injection. The patients were contacted again by phone after the first and fifth years and asked about PMNE symptomatology.

RESULTS

None of the patients had complications. No significant difference in pinch strength was observed following Btx-A injection, but there was significant improvement in grip strength, 2-point discrimination, and Q-DASH and VAS pain scores.

CONCLUSION

The outcomes of our study were promising: Btx-A injection improved symptoms in patients with PMNE.

LEVEL OF EVIDENCE

Level IV.

Is Botulinum Toxin Effective in Treating Orofacial Neuropathic Pain Disorders? A Systematic Review

BACKGROUND

The aim of this paper is to provide a systematic review of the literature regarding the clinical use of botulinum toxin (BTX) to treat various orofacial neuropathic pain disorders (NP).

METHODS

A comprehensive literature search was conducted using Medline, Web of Science, and the Cochrane Library databases. Only randomized clinical trials (RCT) published between 2003 and the end of June 2023, investigating the use of BTX to treat NP, were selected. PICO guidelines were used to select and tabulate the articles.

RESULTS

A total of 6 RCTs were selected. Five articles used BTX injections to treat classical trigeminal neuralgia, and one to treat post-herpetic neuralgia. A total of 795 patients received BTX injections. The selected studies utilised different doses and methods of injections and doses. All the selected studies concluded superiority of BTX injections over placebo for reducing pain levels, and 5 out 6 of them highlighted an improvement in the patient's quality of life. Most of the studies reported transient and mild side effects.

CONCLUSION

There is evidence of the efficacy of BTX injections in orofacial pain management. However, improved study protocols are required to provide direction for the clinical use of BTX to treat various orofacial neuropathic pain disorders.

Novel botulinum neurotoxin-A tibial nerve perineural injection to alleviate overactive bladder symptoms in male rats

Although tibial nerve modulation has shown to induce positive changes in the overactive bladder (OAB), prolonged therapeutic effects using percutaneous stimulation have not yet been achieved. Intradetrusor onabotulinum toxin A injection can provide prolonged therapeutic effects; however, its delivery requires invasive measures. By applying local relief of tibial nerve neural entrapment with onabotulinum toxin A injection, this study investigated the feasibility and efficacy of combining the abovementioned two therapeutic strategies. An OAB animal model was developed using 12 adult Sprague-Dawley rats with cyclophosphamide intraperitoneal injection. A perineural injection site comparable to the tibial nerve perineural injection site and corresponding to that in humans was identified and developed in rats. The toxin was injected five days after establishing the OAB. The incision was made in the skin on the lateral surface of the thigh. The biceps femoris muscle was cut across, exposing the sciatic nerve and its three terminal branches: the sural, common peroneal, and tibial nerves, and 100 units of onabotulinum toxin A was injected into the surrounding tissue. Five days following injection, cystometry was performed. Inter-contraction time, contraction pressure, and interval of the disease state improved with statistical significance. The OAB animal model showed significant improvement with the tibial nerve perineural injection of botulinum toxin, thereby suggesting the possibility of a comparable treatment adaptation in humans.

Reasons and Determinants of BoNT-A Treatment Discontinuation in Patients Living with Spasticity: A 10-Year Retrospective Analysis

BACKGROUND

The present study aimed to evaluate the reasons and determinants of BoNT-A discontinuation in patients with stroke, multiple sclerosis, spinal cord injury, and traumatic brain injury.

METHODS

It is a retrospective study of 56 discontinuer patients treated with botulinum toxin between January 2011 and December 2021. Discontinuation rates and their predictors were estimated using Kaplan-Meier, Log rank test, and Cox's regression method of analyses.

RESULTS

The mean age was 56.54 years, 53.57% were affected by post-stroke spasticity, 17.86% by spinal cord injury, 12.5% and 16.07% by traumatic brain injury and multiple sclerosis, respectively. The median discontinuation time was 5 months. The main reason for discontinuation were logistic problems (37%) and orthopedic surgeries or intrathecal baclofen (27%). Discontinuers were more likely to have severe spasticity (R = 1.785), have no pain (HR = 1.320), no access to rehabilitation services (HR = 1.402), and have cognitive impairment (HR = 1.403).

CONCLUSIONS

The main reasons for discontinuation are related to logistic issues (due to distance or the absence of an adequate caregiver) and surgical interventions for spasticity, including intrathecal baclofen. It is crucial to identify possible predictors of discontinuation to improve the effectiveness of a multidisciplinary management. The study confirms the crucial role of rehabilitation and caregivers in achieving better long-term outcomes.

Multidimensional Effectiveness of Botulinum Toxin in Neuropathic Pain: A Systematic Review of Randomized Clinical Trials

Although botulinum toxin (BoNT) has been suggested as a treatment to counter neuropathic pain, no previous systematic reviews investigated the multidimensional effects of BoNT on pain relief and Health-Related Quality of Life (HR-QoL). The aim of this systematic review is to summarize the current evidence on the effectiveness of BoNT treatment for neuropathic pain, and to characterize its multidimensional effectiveness in order to guide physicians in clinical practice. Five databases were systematically searched up to 4 April 2022, to identify randomized controlled trials satisfying the following criteria: adults suffering from neuropathic pain, BoNT administration, any comparator, multidimensional assessment of pain as primary outcome, HR-QoL, physical function, anxiety and depression, and sleep quality as secondary outcomes. Twelve studies were included. The multidimensional pain scales used were short-form McGill Pain Questionnaire, Neuropathic pain scale, Neuropathic Pain Symptom Inventory, International SCI Pain Basic Data Set, West Haven-Yale Multidimensional Pain Inventory, Brief Pain Inventory, and Douleur Neuropathique 4. These scales highlighted the positive effects of BoNT administration. According to the Jadad scale, all the RCTs included were high-quality studies. BoNT administration might be effectively introduced in the comprehensive management of neuropathic pain. Further research should focus on optimal and cost-effective therapeutic protocols.

Effects of a preoperative neuromobilization program offered to individuals with carpal tunnel syndrome awaiting carpal tunnel decompression surgery: A pilot randomized controlled study

STUDY DESIGN

Pilot randomized controlled trial with parallel groups.

INTRODUCTION

Engaging individuals with carpal tunnel syndrome (CTS) awaiting carpal tunnel decompression surgery in a preoperative rehabilitation program may mitigate pain and sensorimotor impairments, enhance functional abilities before surgery, and improve postoperative outcomes.

PURPOSE OF THE STUDY

To assess the feasibility and the efficacy of a novel preoperative neuromobilization exercise program (NEP).

METHODS

Thirty individuals with CTS were randomly allocated into a four-week home-based neuromobilization exercise group or a standard care group while awaiting surgery. Outcome measures included feasibility (ie, recruitment, attrition, adherence, satisfaction, and safety) and efficacy metrics (ie, median nerve integrity and neurodynamics, tip pinch grip, pain, and upper limb functional abilities) collected before (ie, at the baseline and about four weeks later) and four weeks after surgery.

RESULTS

Thirty individuals with CTS were recruited (recruitment rate = 11.8%) and 25 completed the study (attrition rate = 16.7%). Adherence (94%) and satisfaction with the program (eg, enjoy the exercises and likeliness to repeat the NEP (≥4.2/5) were high and no serious adverse event was reported. NEP-related immediate pre- and post-surgery beneficial effects on pain interference were documented (P = .05, η² = .10), whereas an overall increased neurodynamics (P = .04, η² = .11) and decreased pain severity (P = .01, η² = .21) were observed.

DISCUSSION

Engaging in the proposed NEP has limited beneficial effect as a stand-alone intervention on pre- and post-surgery outcomes for individuals with CTS. Expanding the program's content and attribute by adding other components including desensitization maneuvers and novel therapies promoting corticospinal plasticity is recommended.

CONCLUSION

A preoperative NEP completed by individuals with CTS awaiting surgery is feasible, acceptable, and safe. However, given the limited beneficial effectsof the program, revision of its content and attributes is recommended before proceeding to large-scale trials.

Botulinum Neurotoxin for the Treatment of Neuropathic Pain

Botulinum neurotoxin is widely used for the treatment of central and peripherical neurological conditions. Initially used to treat strabismus, over the years its use has been expanded also to spasticity and other neurological disorders. This review summarizes the evidence from the published literature regarding its effect on neuropathic pain. Almost all investigations were performed using onabotulinum toxin type A (BoNT/A). Most studies provided positive results, even though toxin formulation, dose, dilution, injection techniques, and sites are heterogeneous across studies. Future larger, high-quality, specifically designed clinical trials are warranted to confirm botulinum neurotoxin efficacy in neuropathic pain.

Botulinum toxin-A for the treatment of neuralgia: a systematic review and meta-analysis

AIM

This meta-analysis was performed to evaluate the efficacy and safety of botulinum toxin-A (BTX-A) for the treatment of neuralgia.

METHODS

We searched PubMed, EMBASE, and Cochrane databases to identify randomized controlled trials (RCTs) comparing BTX-A treatment with saline for alleviating neuropathic pain. Primary outcome measures were pain scores up to 24 weeks after treatment. Secondary outcomes were hours of sleep, Short Form-36 (SF-36) life quality questionnaire, and adverse events. We used Review Manager 5.3 for the data analyses.

RESULTS

Twelve RCTs were included (n=495). Pain scores in the BTX-A group were significantly lower compared to the saline group at 4 weeks (mean difference [MD] =-1.64, 95% CI [-3.21, -0.07], P=0.04), 12 weeks (MD =-1.49, 95% CI [-2.05, -0.93], P<0.00001), and 24 weeks (MD =-1.61, 95% CI [-2.81, -0.40], P=0.009). There were no significant differences in hours of sleep, SF-36 questionnaire, or the incidence of injection pain or hematoma between the two groups. No serious adverse events associated with BTX-A were noted. Fourteen out of 108 patients (12.9%) with trigeminal neuralgia experienced mild facial asymmetry after the BTX-A treatment.

CONCLUSION

Based on the current evidence, BTX-A may be an effective and safe option for the treatment of neuralgia. Due to the limited number of patients included in this meta-analysis, more trials are still needed to confirm these results.

Placebo analgesia persists during sleep: An experimental study

Although placebo analgesia is a well-recognized phenomenon with important clinical implications, the possibility that placebo effects occur during sleep has received little attention. This experimental study examined whether responsiveness to acute heat pain stimuli applied during sleep could be reduced following a placebo conditioning procedure administered before sleep. Healthy individuals (n = 9) underwent polysomnographic recordings for one habituation night followed by one placebo analgesia night and one control night in counterbalanced order. Conditioning induced robust analgesia expectations before the placebo night. In the morning after the placebo night, participants reported less nocturnal pain, anxiety, and associated sleep disturbance (all p's < 0.05) compared to the control night. Furthermore, placebo induction produced a 10% reduction in brain arousals evoked by noxious stimuli during rapid-eye-movement (REM) sleep (p = 0.03), consistent with our previous findings suggesting that analgesia expectations are reprocessed during REM sleep. In contrast, arousals increased by 14% during slow wave sleep (SWS) (p = 0.02). In the morning after the last recording night, placebo testing administered as a manipulation check confirmed that typical placebo analgesic responses were produced during waking (p's < 0.05). These results suggest that analgesia expectations developed before sleep reduced nocturnal pain perception and subjective sleep disturbances and activated brain processes that modulate incoming nociceptive signals differentially according to sleep stage. These results need to be replicated in future studies exploring how analgesia expectations may be reactivated during different sleep stages to modulate nociceptive responses.

Botulinum toxin treatment of pain syndromes -an evidence based review

This review evaluates the existing level of evidence for efficacy of BoNTs in different pain syndromes using the recommended efficacy criteria from the Assessment and Therapeutic Subcommittee of the American Academy of Neurology. There is a level A evidence (effective) for BoNT therapy in post-herpetic neuralgia, trigeminal neuralgia, and posttraumatic neuralgia. There is a level B evidence (probably effective) for diabetic neuropathy, plantar fasciitis, piriformis syndrome, pain associated with total knee arthroplasty, male pelvic pain syndrome, chronic low back pain, male pelvic pain, and neuropathic pain secondary to traumatic spinal cord injury. BoNTs are possibly effective (Level C -one class II study) for female pelvic pain, painful knee osteoarthritis, post-operative pain in children with cerebral palsy after adductor release surgery, anterior knee pain with vastus lateralis imbalance. There is a level B evidence (one class I study) that BoNT treatment is probably ineffective in carpal tunnel syndrome. For myofascial pain syndrome, the level of evidence is U (undetermined) due to contradicting results. More high quality (Class I) studies and studies with different types of BoNTs are needed for better understanding of the role of BoNTs in pain syndromes.

Conservative therapeutic management of carpal tunnel syndrome

ABSTRACT Carpal tunnel syndrome is the most prevalent nerve compression and can be clinically or surgically treated. In most cases, the first therapeutic alternative is conservative treatment but there is still much controversy regarding the most effective modality of this treatment. In this study, we critically evaluated the options of conservative treatment for carpal tunnel syndrome, aiming to guide the reader through the conventional options used in this therapy.

Botulinum Toxin for the Treatment of Neuropathic Pain

Botulinum toxin (BoNT) has been used as a treatment for excessive muscle stiffness, spasticity, and dystonia. BoNT for approximately 40 years, and has recently been used to treat various types of neuropathic pain. The mechanism by which BoNT acts on neuropathic pain involves inhibiting the release of inflammatory mediators and peripheral neurotransmitters from sensory nerves. Recent journals have demonstrated that BoNT is effective for neuropathic pain, such as postherpetic neuralgia, trigeminal neuralgia, and peripheral neuralgia. The purpose of this review is to summarize the experimental and clinical evidence of the mechanism by which BoNT acts on various types of neuropathic pain and describe why BoNT can be applied as treatment. The PubMed database was searched from 1988 to May 2017. Recent studies have demonstrated that BoNT injections are effective treatments for post-herpetic neuralgia, diabetic neuropathy, trigeminal neuralgia, and intractable neuropathic pain, such as poststroke pain and spinal cord injury.

A structured literature synthesis of wrist outcome measures: An evidence-based approach to determine use among common wrist diagnoses

STUDY DESIGN

Structured literature synthesis.

INTRODUCTION

Hand therapists and researchers have numerous options when selecting outcome measures for patients with wrist pathologies. An evidence-based approach to determining which measures are used most often can inform choices.

PURPOSE OF THE STUDY

To describe how frequently outcome measures are used in recent randomized controlled trials of patients with wrist diagnoses. Identifying assessment design and related International Classification of Functioning, Disability and Health (ICF) domains provides additional consideration for selection.

METHODS

Systematic PubMed and Cumulative Index to Nursing and Allied Health Literature searches for the time frame between January 2005 and March 2015 captured measures used in randomized controlled trials researching wrist-specific fractures, ligament injuries, nerve injuries, arthritis/arthroplasty, or stress injuries/wrist pain.

RESULTS

Three most frequent measures used within each diagnostic category are detailed with assessment design described and ICF domain identified. Across diagnoses, grip/pinch strength and Disabilities of Arm, Shoulder and Hand were the most frequently used physical and patient-reported outcome measures, respectively. The Jebsen-Taylor Hand Function Test was the most frequently used performance measure.

DISCUSSION AND CONCLUSIONS

Consideration of the evidence, ICF domains, wrist diagnoses, and assessment design can help hand therapists select the measure most appropriate for use.

LEVEL OF EVIDENCE

2a.

Pulsed magnetic field versus ultrasound in the treatment of postnatal carpal tunnel syndrome: A randomized controlled trial in the women of an Egyptian population

The aim of this study was to compare the effects of pulsed electromagnetic field versus pulsed ultrasound in treating patients with postnatal carpal tunnel syndrome. The study was a randomized, double-blinded trial. Forty postnatal female patients with idiopathic carpal tunnel syndrome were divided randomly into two equal groups. One group received pulsed electromagnetic field, with nerve and tendon gliding exercises for the wrist, three times per week for four weeks. The other group received pulsed ultrasound and the same wrist exercises. Pain level, sensory and motor distal latencies and conduction velocities of the median nerve, functional status scale and hand grip strength were assessed pre- and post-treatment. There was a significant decrease (P < 0.05) in pain level, sensory and motor distal latencies of the median nerve, and significant increase (P < 0.05) in sensory and motor conduction velocities of the median nerve and hand grip strength in both groups, with a significant difference between the two groups in favour of pulsed electromagnetic field treatment. However, the functional status scale showed intergroup no significant difference (P > 0.05). In conclusion, while the symptoms were alleviated in both groups, pulsed electromagnetic field was more effective than pulsed ultrasound in treating postnatal carpal tunnel syndrome.

A systematic review of conservative treatment of carpal tunnel syndrome

Objective : To assess the effectiveness of conservative therapy in carpal tunnel syndrome.

Data sources : A computer-aided search of MEDLINE and the Cochrane Collaboration was conducted for randomized controlled trials (RCTs) from January 1985 to May 2006.

Review methods : RCTs were included if: (1) the patients, with clinically and electrophysiologically confirmed carpal tunnel syndrome, had not previously undergone surgical release, (2) the efficacy of one or more conservative treatment options was evaluated, (3) the study was designed as a randomized controlled trial. Two reviewers independently selected the studies and performed data extraction using a standardized form. In order to assess the methodological quality, the criteria list of the Cochrane Back Review Group for systematic reviews was applied. The different treatment methods were grouped (local injections, oral therapies, physical therapies, therapeutic exercises and splints).

Results : Thirty-three RCTs were included in the review. The studies were analysed to determine the strength of the available evidence for the efficacy of the treatment. Our review shows that: (1) locally injected steroids produce a significant but temporary improvement, (2) vitamin B6 is ineffective, (3) steroids are better than non-steroidal anti-inflammatory drugs (NSAIDs) and diuretics, but they can produce side-effects, (4) ultrasound is effective while laser therapy shows variable results, (5) exercise therapy is not effective, (6) splints are effective, especially if used full-time.

Conclusion : There is: (1) strong evidence (level 1) on efficacy of local and oral steroids; (2) moderate evidence (level 2) that vitamin B6 is ineffective and splints are effective and (3) limited or conflicting evidence (level 3) that NSAIDs, diuretics, yoga, laser and ultrasound are effective whereas exercise therapy and botulinum toxin B injection are ineffective.

A Bayesian network meta-analysis: Comparing the clinical effectiveness of local corticosteroid injections using different treatment strategies for carpal tunnel syndrome

BACKGROUND

Local corticosteroid injections are commonly used to improve the short-term symptomatic severity and the functional status of the hands affected by carpal tunnel syndrome. We conducted a systematic review and Bayesian network-meta-analysis to compare the clinical effectiveness of local corticosteroid injections using different injection approaches.

METHODS

Electronic literature in Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Web of Science, and other sources were searched to identify clinical studies comparing different injection approaches with each other or placebo for carpal tunnel syndrome. Two review authors conducted selection of studies, data extraction, and assessment of risk of bias independently. Random-effects models were used to conduct the pairwise meta-analysis and the Bayesian network meta-analysis.

RESULTS

Overall, 10 studies with 633 patients were included in the systematic review. Among the injection approaches, local corticosteroid injections using the ultrasound-guided in-plane injection (Ulnar-I) approach was the best treatment strategy for clinical response (median OR versus placebo 128.30, 95% CrI 9.76 to 2299.00), change in symptom severity scale (median MD versus placebo -1.16, 95% CrI -1.95 to -0.38) , and change in functional status scale (median MD versus placebo -0.74, 95% CrI -2.00 to 0.52) at short-term follow-up period in the network meta-analysis. Local corticosteroid injections using other injection approaches were better than placebo for clinical response (for the PI approach, median OR versus placebo 8.85, 95% CrI 3.00 to 33.15; for the DI approach, median OR versus placebo 7.00, 95% CrI 0.53 to 118.80) , change in symptom severity scale (for the Ulnar-O approach, median MD versus placebo -0.78, 95% CrI -1.43 to -0.16; for the PI approach, median MD versus placebo -0.58, 95% CrI -0.95 to -0.22), and change in functional status scale (for the Ulnar-O approach, median MD versus placebo -0.63, 95% CrI -1.67 to 0.43; for the PI approach, median MD versus placebo -0.46, 95% CrI -1.11 to 0.21) at short-term follow-up period. The quality of studies is good.

CONCLUSIONS

According to our analyses, the ultrasound-guided in-plane injection (Ulnar-I) approach was the most effective treatment among the injection approaches for carpal tunnel syndrome.

Botulinum Toxin for Neuropathic Pain: A Review of the Literature

Botulinum neurotoxin (BoNT), derived from Clostridium botulinum, has been used therapeutically for focal dystonia, spasticity, and chronic migraine. Its spectrum as a potential treatment for neuropathic pain has grown. Recent opinions on the mechanism behind the antinociceptive effects of BoNT suggest that it inhibits the release of peripheral neurotransmitters and inflammatory mediators from sensory nerves. There is some evidence showing the axonal transport of BoNT, but it remains controversial. The aim of this review is to summarize the experimental and clinical evidence of the antinociceptive effects, mechanisms, and therapeutic applications of BoNT for neuropathic pain conditions, including postherpetic neuralgia, complex regional pain syndrome, and trigeminal neuralgia. The PubMed and OvidSP databases were searched from 1966 to May 2015. We assessed levels of evidence according to the American Academy of Neurology guidelines. Recent studies have suggested that BoNT injection is an effective treatment for postherpetic neuralgia and is likely efficient for trigeminal neuralgia and post-traumatic neuralgia. BoNT could also be effective as a treatment for diabetic neuropathy. It has not been proven to be an effective treatment for occipital neuralgia or complex regional pain syndrome.

Botulinum toxin for neuropathic pain and spasticity: an overview

In recent years, a large body of data has surfaced reporting the therapeutic benefit of botulinum toxin injection in multiple conditions. The aim of this review is: to summarize the highest quality literature pertaining to clinical application of botulinum toxin in neuropathic pain conditions including postherpetic neuralgia, trigeminal neuralgia, diabetic polyneuropathy, post-traumatic neuralgia, carpal tunnel syndrome, complex regional pain syndrome, phantom limb and stump pain, and occipital neuralgia; to provide an overview of the clinical trials using botulinum toxin in adult spasticity; and to assign levels of evidence according to the American Academy of Neurology guidelines. In summary, there is level A evidence for established efficacy in postherpetic neuralgia and adult spasticity; level B evidence for probable efficacy in trigeminal neuralgia and post-traumatic neuralgia; level B evidence for probable lack of efficacy in carpal tunnel syndrome; level C evidence for possible efficacy in diabetic polyneuropathy; and level U (insufficient) evidence in complex regional pain syndrome, phantom limb and stump pain, and occipital neuralgia.

Analysis of scientific truth status in controlled rehabilitation trials

RATIONALE, AIMS AND OBJECTIVES

Systematic reviews, meta-analyses and clinical guidelines (reviews) are intended to inform clinical practice, and in this sense can be thought of as scientific truthmakers. High-quality controlled trials should align to this truth, and method quality markers should predict truth status. We sought to determine in what way controlled trial quality relates to scientific truth, and to determine predictive utility of trial quality and bibliographic markers.

METHOD

A sample of reviews in rehabilitation medicine was examined. Two scientific truth dimensions were established based on review outcomes. Quality and bibliographic markers were extracted from associated trials for use in a regression analysis of their predictive utility for trial truth status. Probability analysis was undertaken to examine judgments of future trial truth status.

RESULTS

Of the 93 trials included in contemporaneous reviews, overall, n = 45 (48%) were true. Randomization was found more in true trials than false trials in one truth dimension (P = 0.03). Intention-to-treat analysis was close to significant in one truth dimension (P = 0.058), being more commonly used in false trials. There were no other significant differences in quality or bibliographic variables between true and false trials. Regression analysis revealed no significant predictors of trial truth status. Probability analysis reported that the reasonable chance of future trials being true was between 2 and 5%, based on a uniform prior.

CONCLUSIONS

The findings are at odds with what is considered gold-standard research methods, but in line with previous reports. Further work should focus on scientific dynamics within healthcare research and evidence-based practice constructs.

Use of botulinum toxin in musculoskeletal pain

Chronic musculoskeletal pain is a common cause of chronic pain, which is associated with a total cost of $635 billion per year in the U.S. Emerging evidence suggests an anti-nociceptive action of botulinum toxin, independent of its muscle paralyzing action. This review provides a summary of data from both non-randomized and randomized clinical studies of botulinum toxin in back pain and various osteoarticular conditions, including osteoarthritis, tennis elbow, low back pain and hand pain. Three randomized controlled trials (RCTs) of small sizes provide evidence of short-term efficacy of a single intra-articular injection of 100 units of botulinum toxin A (BoNT/A) for the relief of pain and the improvement of both function and quality of life in patients with chronic joint pain due to arthritis. Three RCTs studied intramuscular BoNT/A for tennis elbow with one showing a significant improvement in pain relief compared with placebo, another one showing no difference from placebo, and the third finding that pain and function improvement with BoNT/A injection were similar to those obtained with surgical release. One RCT of intramuscular BoNT/A for low back pain found improvement in pain and function compared to placebo. Single RCTs using local injections of BoNT in patients with either temporomandibular joint (TMJ) pain or plantar fasciitis found superior efficacy compared to placebo. One RCT of intramuscular BoNT/B in patients with hand pain and carpal tunnel syndrome found improvement in pain in both BoNT/B and placebo groups, but no significant difference between groups. Most evidence is based on small studies, but the use of BoNT is supported by a single, and sometimes up to three, RCTs for several chronic musculoskeletal pain conditions. This indicates that botulinum toxin may be a promising potential new treatment for chronic refractory musculoskeletal pain. Well-designed large clinical trials are needed.

Carpal tunnel syndrome. Part I: effectiveness of nonsurgical treatments--a systematic review

OBJECTIVE

To review literature systematically concerning effectiveness of nonsurgical interventions for treating carpal tunnel syndrome (CTS).

DATA SOURCES

The Cochrane Library, PubMed, EMBASE, CINAHL, and PEDro were searched for relevant systematic reviews and randomized controlled trials (RCTs).

STUDY SELECTION

Two reviewers independently applied the inclusion criteria to select potential studies.

DATA EXTRACTION

Two reviewers independently extracted the data and assessed the methodologic quality.

DATA SYNTHESIS

A best-evidence synthesis was performed to summarize the results of the included studies. Two reviews and 20 RCTs were included. Strong and moderate evidence was found for the effectiveness of oral steroids, steroid injections, ultrasound, electromagnetic field therapy, nocturnal splinting, and the use of ergonomic keyboards compared with a standard keyboard, and traditional cupping versus heat pads in the short term. Also, moderate evidence was found for ultrasound in the midterm. With the exception of oral and steroid injections, no long-term results were reported for any of these treatments. No evidence was found for the effectiveness of oral steroids in long term. Moreover, although higher doses of steroid injections seem to be more effective in the midterm, the benefits of steroids injections were not maintained in the long term. For all other nonsurgical interventions studied, only limited or no evidence was found.

CONCLUSIONS

The reviewed evidence supports that a number of nonsurgical interventions benefit CTS in the short term, but there is sparse evidence on the midterm and long-term effectiveness of these interventions. Therefore, future studies should concentrate not only on short-term but also on midterm and long-term results.

Evidence supporting the use of physical modalities in the treatment of upper extremity musculoskeletal conditions

PURPOSE OF REVIEW

To evaluate recent trials and reviews of physical modalities and conservative treatments for selected upper extremity musculoskeletal conditions for evidence supporting their use.

RECENT FINDINGS

Recent evidence suggests that many localized tendinopathies are related more to degenerative than inflammatory processes. With this realization, there is increased emphasis on finding new modalities to treat tendinopathies and other localized musculoskeletal conditions that rely on other than anti-inflammatory mechanisms. Although there is good evidence to support the short-term benefits of corticosteroid injections, convincing evidence in support of other conservative treatments and modalities is generally lacking. Extracorpal shock wave therapy may have significant clinical benefit for calcific tendinitis; however, it requires intravenous sedation in most cases and does not appear to be effective in lateral epicondylitis. The most consistent positive treatment effects for rotator cuff tendinitis were achieved by ultrasound-guided subacromial corticosteroid injection as well as manual therapy in conjunction with therapeutic exercise.

SUMMARY

Although there is evidence supporting the use of several different physical modalities and conservative treatments for upper extremity musculoskeletal conditions, there is a strong need for larger, higher quality randomized controlled trials. Although most studies are able to demonstrate short-term benefits, there is a lack of high-quality data demonstrating that these conservative treatments have long-term benefits, particularly, with regard to functional outcomes.

Botulinum toxin therapy for osteoarticular pain: an evidence-based review

Botulinum (BoNT) toxin has been used for its muscle-paralyzing action in conditions such as treatment of wrinkles, cervical dystonia and blephrospasm. There is preclinical and emerging clinical evidence of another mechanism of action of BoNT, namely, an antinociceptive action. In this review, we provide an evidence-based review of clinical studies of BoNT in osteoarticular conditions, such as osteoarthritis, tennis elbow, low back pain, and hand pain. Many randomized controlled trials (RCTs) found evidence of short-term efficacy of an injection of BoNT in relief of pain, and in some cases, improvement of function and quality of life. However, more clinical trials are needed to better define the clinical use of BoNT for treatment of refractory osteoarticular pain.

Role of botulinum toxin in hand and upper limb disorders relevant to hand therapy

Introduction

This article reviews the mechanism of action of botulinum toxin and provides an overview of its use in hand disorders relevant to hand therapy such as hyperhidrosis, spasticity, dystonia, tremor, Parkinson's, obstetrical brachial plexus palsy, flexor tendon rehabilitation, lateral epicondylitis, Raynaud's and carpal tunnel syndrome.

Methods

A narrative review of the literature retrieved through electronic databases using keywords botulinum toxin, hand, therapy, and reviewing the bibliographic references cited.

Results

Sixty-five original articles and meta-analyses were reviewed. The number and quality of the published reports for each disorder are very variable but generally botulinum toxin is reported to be an effective adjunct to therapy in the treatment of a wide variety of hand and upper limb pathologies.

Discussion

A surprising number of hand and upper limb conditions have been successively treated with botulinum toxin, but most require botulinum toxin to be used in conjunction with hand therapy to achieve more effective outcomes for longer duration. Neuromuscular disorders seem to be most responsive to botulinum toxin treatment. Therapists should be aware of the potential benefits of botulinum toxin injections for a wide range of hand disorders and when appropriate discuss these with patients and other health professionals.

Conclusion

Botulinum toxin has an effective and growing role in hand therapy.

Evidence for the use of botulinum toxin in the chronic pain setting--a review of the literature

A significant proportion of chronic pain is of musculoskeletal origin. Botulinum toxin (BTX) has been successfully used in the treatment of spasmodic torticollis, limb dystonia, and spasticity. Investigators have, thus, become interested in its potential use in treating many chronic pain conditions. Practitioners have used BTX, outside the product license, in the treatment of refractory myofascial pain syndrome and neck and low back pain (LBP). This article reviews the current evidence relating to chronic pain practice. There is evidence supporting the use of both BTX type A and type B in the treatment of cervical dystonias. The weight of evidence is in favor of BTX type A as a treatment in: pelvic pain, plantar fasciitis, temporomandibular joint dysfunction associated facial pain, chronic LBP, carpal tunnel syndrome, joint pain, and in complex regional pain syndrome and selected neuropathic pain syndromes. The weight of evidence is also in favor of BTX type A and type B in piriformis syndrome. There is conflicting evidence relating to the use of BTX in the treatment whiplash, myofascial pain, and myogenous jaw pain. It does appear that BTX is useful in selected patients, and its duration of action may exceed that of conventional treatments. This seems a promising treatment that must be further evaluated.

Nonpharmacologic Effects of Botulinum Toxin on the Life Quality of Patients with Spasmodic Dysphonia

OBJECTIVE

Botulinum toxin (BT) injection improves objective and subjective voice measurements in spasmodic dysphonia; however, it is not clear whether the results are entirely caused by the neuromuscular blocking effects of BT or whether other factors (e.g., psychological or emotional) play a part. The aim of this study is to investigate whether nonpharmacologic factors contribute to the changes observed in the quality of life (QoL) after BT treatment of spasmodic dysphonia.

STUDY DESIGN

Prospective cohort study.

METHODS

Thirty-eight consecutive spasmodic dysphonic patients attending for repeat BT injections were investigated by recording their Voice Handicap Index (VHI) scores at three time points: 1) immediately prior to injection (baseline), 2) 1 day postinjection (when least pharmacologic change is expected), and 3) 2 weeks postinjection (when most pharmacologic change is expected). The changes in the total and domain VHI scores were compared between the two postinjection scores and the baseline value using two-way analysis of variance and the post hoc Bonferroni test.

RESULTS

Most of the change in VHI score occurred between the baseline and first postinjection measurement. For two of the domains (total and emotional), the change was statistically significant. The change between the two postinjection assessments was minimal, and no domain showed statistically significant change.

CONCLUSIONS

Our data indicate that the early improvements in QoL after BT injection can only in small part be attributed to the neurotoxic effects of the agent. We cannot say whether the reported effects in our study are attributable to a strong placebo response or are a real consequence of the patient's changing emotional state.

Efficacy of botulinum toxin type a in the relief of Carpal tunnel syndrome: A preliminary experience

BACKGROUND AND OBJECTIVES

Botulinum toxin type A has been shown to relieve primary headaches, myofascial pain and various neuropathic pains. Carpal tunnel syndrome (CTS) is a common disorder resulting from median nerve compression at the wrist. As reports of botulinum toxin A in the treatment of CTS were limited, this study set out to evaluate the safety and tolerability of botulinum toxin A and its effects on the relief of nerve entrapment and pain in patients with CTS.

METHODS

We conducted an open-label, prospective pilot study using 60 units of botulinum toxin A injected intracarpally in patients with primary CTS. Changes in median nerve conduction velocities, distal latencies, compound muscle action potentials and visual analogue scale (VAS) pain scores were evaluated for 3 months following injection. All adverse experiences, reported spontaneously or observed directly by the investigator, were recorded.

RESULTS

Five women aged 52.2 +/- 2.5 years with 1-2 years' history of CTS were enrolled. Botulinum toxin A was well tolerated and safe. No exacerbated hand weakness was observed in any of the patients. At 3 months, pain was lessened in three patients, remained static in one patient, and was aggravated in one patient. The VAS pain score showed a trend to improvement during the 3 months of follow-up, although it did not reach statistical significance (p = 0.2).

CONCLUSION

Our data suggest long-lasting antinociceptive effects of botulinum toxin A rather than electrophysiological restoration in patients with CTS. Intracarpal injection of botulinum toxin A was shown to be well tolerated and safe. A double-blind, placebo-controlled trial of botulinum toxin A in CTS is warranted since the current study may have been confounded by the placebo effect of intracarpal injection.