Intra-articular botulinum toxin injection in complex regional pain syndrome: Case report and review of the literature

Complete Improvement of Severe Forearm Complex Regional Pain Syndrome with Six High-Dose Incobotulinumtoxin A Injections: Clinical Implications with Respect to the Literature

There is some evidence that injections of botulinum neurotoxin effectively reduce pain in complex regional pain syndromes (CRPSs). But no or little experience appears to exist for the application of incobotulinum neurotoxin type A (incoBoNT/A) in complex pain disorders. Here, a case of CRPS type I, characterized by severe symptoms in the left forearm is presented, showed significant continuous improvement following a series of six repetitive (painful) injections into the finger, hand, and forearm muscles of incoBoNT/A every 3 months, administered at declining doses varying between 500 and 100 U. Remarkably, this treatment regimen led to the complete resolution of pain, vaso- and sudomotor symptoms, and hand dystonia. This highlights the possible efficacy of incoBoNT/A in the treatment of CRPS and encourages the further exploration of incoBoNT/A's role in the successful management of complex pain disorders.

The Efficacy of Neuromodulation, Interventional Treatment and Unconventional Therapies in the Treatment of Complex Regional Pain Syndrome: A Systematic Review

Complex regional pain syndrome (CRPS) is a chronic debilitating multisystem neuropathic pain disorder. It is characterized by continuous pain, usually out of proportion to any known tissue injury, vasomotor changes, sudomotor or edema, and motor or trophic changes. The objective of this study is to assess the efficacy of neuromodulation, interventional, and unconventional treatments for CRPS. The primary focus is pain reduction, assessed through various scales, with secondary outcomes examining effects on autonomic, sensory, motor, and psychological aspects, and quality of life. PubMed, Cochrane Library, MDPI, and ScienceDirect databases were thoroughly searched using our detailed search strategy and relevant literature compiled. Articles were assessed using our eligibility criteria and quality appraisal tools. All types of study designs were considered. Initially, 463 articles were identified; after a thorough assessment, 23 articles comprising 2307 patients were shortlisted. Neuromodulation interventions, specifically Dorsal Root Ganglion (DRG) and Spinal Cord Stimulation (SCS) demonstrated statistically significant pain reduction (43-82% and up to 70%, respectively). Both modalities demonstrate improvement in secondary outcomes and quality of life. Interventional interventions, specifically nerve blockade ranging from sympathetic, stellate ganglion, and regional nerve blocks, all demonstrate varying levels of efficacy on measured pain and secondary outcomes. Unconventional: Botulinum toxin injections through multiple delivery systems demonstrated varying levels of efficacy in treating pain and improving secondary outcomes. In conclusion, DRG stimulation and SCS, nerve blockade, and botulinum toxin all display promise in alleviating symptoms of CRPS. Definite conclusions were not made due to a lack of clinical trial data, and longer multi-year follow-up is recommended.

Intramuscular botulinum toxin-A in complex regional pain syndrome resistant to standard treatment: a case report

OBJECTIVE

To present a patient with complex regional pain syndrome type 1 (CRPS-I) and improvement of contracture of hand muscles and grip strength after successful treatment with botulinum neurotoxin‑A (BoNT-A).

CASE

A 53-year-old woman with CRPS‑I experienced severe allodynia, swelling and autonomic changes in the left hand after a distal radius fracture. Over the succeeding months, she developed contracture of the left hand muscles which was treated with injection of BoNT‑A into the hand muscles (10 points).

RESULTS

In the patient treatment with BoNT‑A an improvement was seen in the hand range of motion (ROM) and grip strength.

CONCLUSION

Successful results can be obtained with BoNT‑A injection in treatment-resistant CRPS‑I cases which may develop joint contracture.

An update on the pharmacotherapeutic options for complex regional pain syndrome

INTRODUCTION

Complex regional pain syndrome (CRPS) is a rare and painful condition that has a wide range of triggering factors, often traumatic, and can present various clinical manifestations. The lack of knowledge about the underlying mechanisms has led to numerous treatment approaches, both conservative and surgical, which work through different mechanisms of action.

AREAS COVERED

In this review, the authors explore the key aspects of CRPS, including definition, diagnostic criteria, pitfalls, pathogenic hypotheses, and treatment strategies with a focus on pharmacotherapy. The review was based on a comprehensive search of the literature using PubMed, while also considering international guidelines for managing CRPS.

EXPERT OPINION

Based on the available evidence, pharmacological interventions appear to be effective in treating CRPS, especially when they target peripheral mechanisms, specifically nociceptive inflammatory pain, and when administered early in the course of the disease. However, there is still a lack of reliable evidence regarding the effects of drugs on central mechanisms of chronic pain in CRPS. In our expert opinion, drug therapy should be initiated as soon as possible, particularly in warm CRPS patient clusters, to prevent significant functional limitations, psychological distress, and negative impacts on individuals' social and economic well-being.

Complex Regional Pain Syndrome: Evidence-Based Advances in Concepts and Treatments

PURPOSE OF REVIEW

This review presents the most current information about the epidemiology of complex regional pain syndrome (CRPS), classification and diagnostic criteria, childhood CRPS, subtypes, pathophysiology, conventional and less conventional treatments, and preventive strategies.

RECENT FINDINGS

CRPS is a painful disorder with multifactorial pathophysiology. The data describe sensitization of the central and peripheral nervous systems, inflammation, possible genetic factors, sympatho-afferent coupling, autoimmunity, and mental health factors as contributors to the syndrome. In addition to conventional subtypes (type I and type II), cluster analyses have uncovered other proposed subtypes. Prevalence of CRPS is approximately 1.2%, female gender is consistently associated with a higher risk of development, and substantial physical, emotional, and financial costs can result from the syndrome. Children with CRPS seem to benefit from multifaceted physical therapy leading to a high percentage of symptom-free patients. The best available evidence along with standard clinical practice supports pharmacological agents, physical and occupational therapy, sympathetic blocks for engaging physical restoration, steroids for acute CRPS, neuromodulation, ketamine, and intrathecal baclofen as therapeutic approaches. There are many emerging treatments that can be considered as a part of individualized, patient-centered care. Vitamin C may be preventive. CRPS can lead to progressively painful sensory and vascular changes, edema, limb weakness, and trophic disturbances, all of which substantially erode healthy living. Despite some progress in research, more comprehensive basic science investigation is needed to clarify the molecular mechanisms of the disease so that targeted treatments can be developed for better outcomes. Incorporating a variety of standard therapies with different modes of action may offer the most effective analgesia. Introducing less conventional approaches may also be helpful when traditional treatments fail to provide sufficient improvement.

Pain Modulation in Chronic Musculoskeletal Disorders: Botulinum Toxin, a Descriptive Analysis

Botulinum neurotoxin (BoNT), a product of Clostridium botulinum, reversibly inhibits the presynaptic release of the neurotransmitter acetylcholine at the neuromuscular junction. In addition, BoNT blocks the transmission of other substances involved in pain perception and, together with a soft-tissue anti-inflammatory effect, may play a role in analgesia. When first-line treatment fails, second-line therapies might include BoNT. Studies on chronic and recurrent pain using different mechanisms offer heterogenous results that must be validated and standardized. Plantar fasciitis, severe knee osteoarthritis, painful knee and hip arthroplasty, antalgic muscular contractures, and neuropathic and myofascial pain syndromes may benefit from the administration of BoNT. Research on this topic has revealed the main musculoskeletal conditions that can benefit from BoNT, stressing the effects, modalities of administration, doses, and schedule.

Subcutaneous BoNT/A Injection for Intractable Pain and Disability in Complex Regional Pain Syndrome: A Case Report

We treated a 51-year-old woman with refractory Complex Regional Pain Syndrome type I (CRPS-I) involving her left hand and forearm with subcutaneous injections of BoNT/A. The injections were performed every 3 months, with a total of six treatments. Each treatment was able to effectively improve pain and motor impairment; however, the duration of the effect was limited to only a few months. BoNT/A could improve patients’ quality of life with CRPS; however, extensive clinical studies are needed to determine its role in clinical practice.

Botulinum toxin injections for shoulder and upper limb pain: a narrative review

Botulinum toxin (BoNT) has been widely employed to treat poststroke spasticity, cervical dystonia and muscle hyperactivity. Recently, BoNT injections are increasingly used in treating musculoskeletal pain. The mechanism of BoNT in pain relief comprises relaxation of overused muscles and inhibition of inflammatory nociceptive cytokines/neurotransmitters. As BoNT injections seem promising in treating painful musculoskeletal disorders, we aimed to investigate its effectiveness in shoulder and upper limb pain. Although the present article is a narrative review, we employed a systematic approach to search for relevant articles in PubMed. A total of 19 clinical studies were included. Here, we observed that intramuscular BoNT injections were helpful in stroke patients with hemiplegic shoulder pain. In shoulder joint pain, intra-articular and intrabursal BoNT injections achieved a longer period of pain relief than corticosteroid injections. Similarly, a more durable effect of intramuscular BoNT than saline injections was seen in shoulder myofascial pain. Its use in complex regional pain syndrome and persistent upper limb pain in breast cancer survivors was insufficient, necessitating more studies. Since not all of the included studies could provide Class I of evidence based on the efficacy criteria used by American Academy of Neurology, controlled clinical trials in a larger number of patients are necessary to verify validity of these findings in the future.

Pharmacotherapeutic options for complex regional pain syndrome

INTRODUCTION

Complex regional pain syndromes (CRPS) are rare painful conditions characterized by considerable variability in possible triggering factors, usually traumatic, and in the clinical scenario. The limited knowledge of the pathophysiological mechanisms has led to countless treatment attempts with multiple conservative and surgical options that act by different mechanisms of action.

AREAS COVERED

In this narrative review, the authors discuss key points about CRPS definitions, diagnostic criteria and pitfalls, pathophysiological hypotheses, and treatment strategies with particular reference to pharmacotherapy. The article was based on a literature search using PubMed while the available guidelines for the management of CRPS were also examined.

EXPERT OPINION

According to the quality of evidence, pharmacological interventions for CRPS seem to be more effective all the more so when they act on peripheral mechanisms, particularly on nociceptive pain, and when applied early in the disease, while reliable evidence about central mechanisms of chronic pain in CRPS is lacking. In our opinion, drug therapy should be preferred as early as possible, particularly in warm forms of CRPS to prevent significant functional limitation, psychological distress, and social and economic fallout.