Quality of life after amputation in patients with advanced complex regional pain syndrome: a systematic review

10. Complex regional pain syndrome

INTRODUCTION

Complex regional pain syndrome (CRPS) is a clinical disorder that can develop following surgery or trauma. Based on the most prominent underlying pathophysiological mechanisms, CRPS can be classified into different subtypes, namely inflammatory, nociplastic/neuropathic, vasomotor, and motor. Depending on the subtype, personalized treatment can be applied. If conservative treatments are insufficient or ineffective, more invasive treatments may be recommended. This article provides an overview of the most recent insights into CRPS and discusses the most common invasive treatments.

METHODS

The literature regarding interventional treatments for CRPS has been systematically reviewed and summarized.

RESULTS

Bisphosphonates are effective in treating the inflammatory subtype, while ketamine can provide pain relief for the nociplastic/neuropathic subtype. Sympathetic blocks are effective in addressing vasomotor disturbances. For patients with refractory symptoms, neurostimulation is a viable option due to its multimechanistic properties for all subtypes. End-of-line motor disturbances may benefit from intrathecal baclofen.

CONCLUSIONS

CRPS is a debilitating condition with an unpredictable course. The effectiveness of treatment varies from patient to patient. When conservative approaches prove insufficient, gradual progression to invasive treatments based on the underlying subtype is recommended.

Quality of life, functioning and participation of adult patients with an amputation following complex regional pain syndrome I or brachial plexus injury: a scoping review protocol

INTRODUCTION

This planned scoping review aims to provide insight into current literature regarding perceived quality of life (QoL), functioning and participation of patients with upper limb amputations (ULA) because of therapy-resistant debilitating complex regional pain syndrome type I (CRPS-I) or brachial plexus injury (BPI). It is important to gain insight into these outcomes, so we can properly inform and select patients eligible for amputation.

METHODS AND ANALYSIS

Joanna Briggs Institute methodology for scoping reviews, Systematic Reviews and Meta-Analyses Scoping Reviews guidelines and Arksey and O'Malley's framework will be used. Studies regarding adult patients with either BPI or CRPS-I who underwent ULA will be considered for inclusion. Studies should include one or more of the following topics: QoL, functioning or participation and should be written in English, German or Dutch. Searches will be conducted in the Cochrane database, PubMed, EMBASE and Google Scholar. Search strings will be provided by a licenced librarian. All relevant literatures will be considered for inclusion, regardless of published date, in order to give a full scope of available literature. Studies will be selected first by title, then abstract and finally by full article by two reviewers who will discuss after every round. A third reviewer will make final decisions to reach consensus if needed. Data will be presented as brief summaries and in tables using a modified data extraction table.

ETHICS AND DISSEMINATION

No ethical approval is required since no original data will be collected. Results will be disseminated through publication in a peer-reviewed journal and presentations at (inter)national conferences.

Complex regional pain syndrome: advances in epidemiology, pathophysiology, diagnosis, and treatment

Complex regional pain syndrome (CRPS) is a rare pain disorder that usually occurs in a limb after trauma. The features of this disorder include severe pain and sensory, autonomic, motor, and trophic abnormalities. Research from the past decade has offered new insights into CRPS epidemiology, pathophysiology, diagnosis, and treatment. Early identification of individuals at high risk of CRPS is improving, with several risk factors established and some others identified in prospective studies during the past 5 years. Better understanding of the pathophysiological mechanisms of CRPS has led to its classification as a chronic primary pain disorder, and subtypes of CRPS have been updated. Procedures for diagnosis have also been clarified. Although effective treatment of CRPS remains a challenge, evidence-based integrated management approaches provide new opportunities to improve patient care. Further advances in diagnosis and treatment of CRPS will require coordinated, international multicentre initiatives.

Causalgia: A Review of Nerve Resection, Amputation, Immunotherapy, and Amputated Limb CRPS II Pathology

BACKGROUND

Causalgia and complex regional pain syndrome (CRPS) type II with nerve injury can be difficult to treat. Surgical peripheral nerve denervation for causalgia has been largely abandoned by pain clinicians because of a perception that this may aggravate a central component (anesthesia dolorosa).

METHODS

We selectively searched Pubmed, Cochrane, MEDLINE, EMBASE, CINAHL Plus, and Scopus from 1947 for articles, books, and book chapters for evidence of surgical treatments (nerve resection and amputation) and treatment related to autoimmunity and immune deficiency with CRPS.

RESULTS

Reviews were found for the treatment of causalgia or CRPS type II (n = 6), causalgia relieved by nerve resection (n = 6), and causalgia and CRPS II treated by amputation (n = 8). Twelve reports were found of autoimmunity with CRPS, one paper of these on associated immune deficiency and autoimmunity, and two were chosen for discussion regarding treatment with immunoglobulin and one by plasma exchange. We document a report of a detailed and unique pathological examination of a CRPS type II affected amputated limb and related successful treatment with immunoglobulin.

CONCLUSIONS

Nerve resection, with grafting, and relocation may relieve uncomplicated causalgia and CRPS type II in some patients in the long term. However, an unrecognized and treatable immunological condition may underly some CRPS II cases and can lead to the ultimate failure of surgical treatments.

The Role of Neuroinflammation in Complex Regional Pain Syndrome: A Comprehensive Review

Complex Regional Pain Syndrome (CRPS) is an excess and/or prolonged pain and inflammation condition that follows an injury to a limb. The pathogenesis of CRPS is multifaceted that remains incompletely understood. Neuroinflammation is an inflammatory response in the peripheral and central nervous systems. Dysregulated neuroinflammation plays a crucial role in the initiation and maintenance of pain and nociceptive neuronal sensitization, which may contribute to the transition from acute to chronic pain and the perpetuation of chronic pain in CRPS. The key features of neuroinflammation encompass infiltration and activation of inflammatory cells and the production of inflammatory mediators in both the central and peripheral nervous systems. This article reviews the role of neuroinflammation in the onset and progression of CRPS from six perspectives: neurogenic inflammation, neuropeptides, glial cells, immune cells, cytokines, and keratinocytes. The objective is to provide insights that can inform future research and development of therapeutic targets for CRPS.

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.

LONG-STANDING COMPLEX REGIONAL PAIN SYNDROME-TYPE I: PERSPECTIVES OF PATIENTS NOT AMPUTATED

Objective

Complex Regional Pain Syndrome type I (CRPS-I) is an often intractable regional pain syndrome, usually affecting limbs in which amputation may be a final resort. Not all patients are suited for amputation.This retrospective case series with explorative interviews aims to gain insight in the quality of life in those who have been denied an amputation and their functioning with CRPS-I.

Patients and methods

Between 2011 and 2017, 37 patients were denied an amputation. Participants were interviewed regarding quality of life, treatments received since their outpatient clinic visit and their experiences at our outpatient clinic.

Results

A total of 13 patients participated. Most patients reported improvements in pain, mobility and overall situation. All patients received treatments after being denied an amputation, with some reporting good results. Many felt they had no part in decision making. Of the 13 participants 9 still had an amputation wish. Our participants scored worse in numerous aspects of their lives compared with patients with an amputation from a previous CRPS-I study of us.

Conclusion

This study shows that amputation should only be considered after all treatments have been tried and failed, since most participants reported improvements in aspects of their functioning over time.

Combined use of peripheral nerve stimulation and dorsal root ganglion stimulation for refractory complex regional pain syndrome type I to avoid amputation: A case report

We describe a case of left foot and ankle complex regional pain syndrome type 1 that necessitated a novel combination of a functioning dorsal root ganglion stimulation and peripheral nerve stimulation. This approach optimized pain relief, functional improvement, and avoided amputation.

Modern Principles of Diagnosis and Treatment in Complex Regional Pain Syndrome

BACKGROUND

Background: Complex regional pain syndrome (CRPS) is a relatively common complication, occurring in 5% of cases after injury or surgery, particularly in the limbs. The incidence of CPRS is around 5-26/100 000. The latest revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-11) now categorizes CRPS as a primary pain condition of multifactorial origin, rather than a disease of the skeletal system or the autonomic nervous system.

METHODS

Method: Based on a selective search of the literature, we summarize current principles for the diagnosis and treatment of CRPS.

RESULTS

Results: Regional findings in CRPS are accompanied by systemic symptoms, especially by neurocognitive disorders of body perception and of symptom processing. The therapeutic focus is shifting from predominantly passive peripheral measures to early active treatments acting both centrally and peripherally. The treatment is centered on physiotherapy and occupational therapy to improve sensory perception, strength, (fine) motor skills, and sensorimotor integration/ body perception. This is supported by stepped psychological interventions to reduce anxiety and avoidance behavior, medication to decrease inflammation and pain, passive physical measures for reduction of edema and of pain, and medical aids to improve functioning in daily life. Interventional procedures should be limited to exceptional cases and only be performed in specialized centers. Spinal cord and dorsal root ganglion stimulation, respectively, are the interventions with the best evidence.

CONCLUSION

Conclusion: The modern principles for the diagnosis and treatment of CRPS consider both, physiological and psychological mechanisms, with the primary goal of restoring function and participation. More research is needed to strengthen the evidence base in this field.

An Algorithm for Elective Amputation Combined with Targeted Muscle Reinnervation in Complex Regional Pain Syndrome—A Perspective

Complex regional pain syndrome (CRPS) can result in a devastating condition. For a small number of patients, there is a non-response to any existing multimodal therapies and they ultimately request amputation. Such a drastic and final decision is not easy to take for both the patient and the surgeon and requires careful and interdisciplinary assessments and considerations. Furthermore, new surgical procedures, such as targeted muscle reinnervation (TMR) and hybrid prosthetic fitting, and multidisciplinary board advice should be included when considering amputation. In order to help other therapeutic teams in decision making for such rare but more than demanding cases, we aimed to propose an advanced algorithm for amputation indications in CRPS patients combining all these new factors. This algorithm consists of extensive pre-operative psychiatric assessment, diagnostic hybrid prosthetic fitting including fMRI analyses, multidisciplinary board advice as well as targeted muscle reinnervation and amputation procedures with final prosthetic fitting and rehabilitation. By involving multiple disciplines, this algorithm should provide optimized and individualized patient treatment on the one hand and a reliable base for decision making for therapists on the other.

Complex Regional Pain Syndrome: A Comprehensive Review

Complex regional pain syndrome (CRPS) is a chronic pain condition often involving hyperalgesia and allodynia of the extremities. CRPS is divided into CRPS-I and CRPS-II. Type I occurs when there is no confirmed nerve injury. Type II is when there is known associated nerve injury. Female gender is a risk factor for developing CRPS. Other risk factors include fibromyalgia and rheumatoid arthritis. Unfortunately, the pathogenesis of CRPS is not yet clarified. Some studies have demonstrated different potential pathways. Neuropathic inflammation, specifically activation of peripheral nociceptors of C-fibers, has been shown to play a critical role in developing CRPS. The autonomic nervous system (ANS) is involved. Depending on whether it is acute or chronic CRPS, norepinephrine levels are either decreased or increased, respectively. Some studies have suggested the importance of genetics in developing CRPS. More consideration is being given to the role of psychological factors. Some association between a history of depression and/or post-traumatic stress disorder (PTSD) and the diagnosis of CRPS has been demonstrated. Treatment modalities available range from physical therapy, pharmacotherapy, and interventional techniques. Physical and occupational therapies include mirror therapy and graded motor imagery. Medical management with non-steroidal anti-inflammatory drugs (NSAIDs) has not shown significant improvement. There have been supporting findings in the use of short-course steroids, bisphosphonates, gabapentin, and ketamine. Antioxidant treatment has also shown some promise. Other pharmacotherapies include low-dose naltrexone and Botulinum toxin A (BTX-A). Sympathetic blocks are routinely used, even if their short- and long-term effects are not clear. Finally, spinal cord stimulation (SCS) has been used for decades. In conclusion, CRPS is a multifactorial condition that still requires further studying to better understand its pathogenesis, epidemiology, genetic involvement, psychological implications, and treatment options. Future studies are warranted to better understand this syndrome. This will provide an opportunity for better prevention, diagnosis, and treatment of CRPS.

Implantation and Control of Wireless, Battery-free Systems for Peripheral Nerve Interfacing

Peripheral nerve interfaces are frequently used in experimental neuroscience and regenerative medicine for a wide variety of applications. Such interfaces can be sensors, actuators, or both. Traditional methods of peripheral nerve interfacing must either tether to an external system or rely on battery power that limits the time frame for operation. With recent developments of wireless, battery-free, and fully implantable peripheral nerve interfaces, a new class of devices can offer capabilities that match or exceed those of their wired or battery-powered precursors. This paper describes methods to (i) surgically implant and (ii) wirelessly power and control this system in adult rats. The sciatic and phrenic nerve models were selected as examples to highlight the versatility of this approach. The paper shows how the peripheral nerve interface can evoke compound muscle action potentials (CMAPs), deliver a therapeutic electrical stimulation protocol, and incorporate a conduit for the repair of peripheral nerve injury. Such devices offer expanded treatment options for single-dose or repeated dose therapeutic stimulation and can be adapted to a variety of nerve locations.

Complex Regional Pain Syndrome: The Importance of Early Diagnosis

Complex regional pain syndrome (CRPS) is a potentially life-altering, neuropathic pain condition that often affects an extremity in response to surgery or even minor trauma. The pain is often disproportionate to the injury sustained or the surgical procedure performed-and it has been described as excruciating and unbearable. CRPS can result in irreversible, disabling changes in the affected limb. In some cases it has resulted in amputation or severe psychological issues. However, CRPS outcomes are generally more successful with early detection and treatment. This article presents an overview of CRPS and discusses the critical role nurses can play in recognizing the condition early, assisting with treatment, and providing psychological support.

Amputation With Osseointegration for Patients With Intractable Complex Regional Pain Syndrome: A Report of 3 Cases

CASES

Three patients with knee-level complex regional pain syndrome type 1 (CRPS1), recalcitrant to conservative interventions, elected for transfemoral amputation and osseointegration. Two patients gained independent ambulation; the third remains on crutches after a disrupted sciatic nerve targeted reinnervation. One uses no pain medication, one is weaning off, and one requires a reduced regimen after revision nerve innervation.

CONCLUSION

Osseointegration seems suitable to optimize rehabilitation after amputation for CRPS1.

Complex regional pain syndrome: an evolving perspective

BACKGROUND

Complex regional pain syndrome (CRPS) is a heterogenous and poorly understood condition that can be provoked by quite minor injuries. The symptoms and signs of CRPS persist, long after the patient has recovered from the inciting event. In some cases, there is a clear association with a peripheral nerve injury. The degree of disability produced by CRPS is often out of proportion to the scale of the original insult and the condition is associated with protracted recovery times and frequent litigation.

METHODS

We have performed a PubMed literature search, referenced landmark papers in the field and included a national expert in peripheral nerve injury and repair in our team of authors.

RESULTS AND CONCLUSIONS

The diagnostic criteria for CRPS have changed repeatedly over the last two centuries and much of the historical literature is difficult to compare with more recent research. In this review article, we consider how our understanding of the condition has evolved and discuss its pathogenesis, its apparent heterogenicity and the various investigations and treatments available to the clinician.

Complex regional pain syndrome: An updated comprehensive review

Complex regional pain syndrome (CRPS) is a complex disorder that can have a significant impact on the quality of life of a person with this syndrome. The diagnosis and treatment of CRPS are often difficult as there is no one confirmatory test and no one definitive treatment. Currently, the most widely accepted clinical diagnostic criteria are the Budapest criteria, which were developed by expert consensus. Though no one single treatment has been found to be universally effective, early detection and an interdisciplinary approach to treatment appear to be key in treating CRPS. This review aims to present up-to-date clinical information regarding the diagnosis and management of CRPS and highlight the potential issues with diagnosis in the neurological population. Ultimately, more research is needed to identify the exact etiology of CRPS in order to help target appropriate therapies. In addition, more randomized controlled trials need to be performed in order to test new therapies or combinations of therapies, including pharmacological, interventional, and behavioral therapies, to determine the best treatment options for this potentially debilitating disorder.

Targeted muscle reinnervation at the time of amputation in the management of complex regional pain syndrome of the lower extremity

BACKGROUND

Complex regional pain syndrome (CRPS) is a chronic, posttraumatic condition defined by severe pain and sensorimotor dysfunction. In cases of severe CRPS, patients request amputation, which may cause phantom limb pain (PLP) and residual limb pain (RLP). Targeted muscle reinnervation (TMR) reduces the risk of PLP and RLP. This report describes the use of TMR at the time of amputation in a series of patients with CRPS.

PATIENTS AND METHODS

Four patients (ages 38-71 years) underwent TMR at the time of amputation for CRPS between April 2018 and January 2019. Three patients had a history of trauma and surgery to the affected limb. All patients attempted pharmacologic and interventional treatments for 1-7 years before requesting amputation. Three patients underwent below-knee amputations (BKA) and one had an above-knee amputation (AKA). Target muscles included the soleus, gastrocnemius, and flexor hallucis longus (BKA), and semitendinosus, biceps femoris, and vastus medialis (AKA). Postoperative phantom and residual limb pain symptoms were collected via a telephone survey adapted from the Patient-Reported Outcomes Measurement Information System (PROMIS).

RESULTS

There were no complications related to the TMR procedure. Average follow-up time was 12.75 months. Patients reported varied outcomes: two had RLP and PLP, one had RLP only, and one had PLP only. All patients reported successful prosthetic use.

CONCLUSION

TMR may be performed at the time of amputation for CRPS. Further study is necessary to determine the effect of TMR on pain, pain medication use, prosthesis use, and other domains of function.