The Effectiveness of Rehabilitation Interventions on Pain and Disability for Complex Regional Pain Syndrome: A Systematic Review and Meta-analysis

The efficacy of an interdisciplinary pain management program for complex regional pain syndrome compared to low back pain and chronic widespread pain: an observational study

BACKGROUND

Little research has assessed the efficacy of interdisciplinary pain management programs (IPMPs) for complex regional pain syndrome (CRPS), whereas evidence shows that IPMPs are effective for low back pain (LBP) and chronic widespread pain (CWP). This study aimed to determine whether outcomes following an IPMP differ for people with CRPS compared to LBP and CWP. In addition, we determined whether it is possible to predict IPMP outcomes using baseline characteristics.

METHODS

People with CRPS (N = 66) who had completed a 3-week IPMP were compared with age- and gender- matched controls with LBP (N = 66) and CWP (N = 66). Measures of pain intensity, pain interference and psychological factors were extracted for pre- and post-program, and at 1, 6, and 12 months. Latent class analysis identified recovery trajectories for pain intensity and pain interference, and χ2 analyses assessed differences between diagnostic groups in recovery trajectories. Machine learning models were implemented to predict recovery trajectories from baseline scores.

RESULTS

Two recovery trajectories for each dependent variable (pain interference and for pain intensity) were identified: Good responders and poorer responders. Following IPMPs, 37% of people belonged to a good responder recovery trajectory for pain interference, and 11% belonged to a good responder recovery trajectory for pain intensity. Recovery trajectories were similar across the three diagnostic groups (CRPS, LBP, CWP) for pain interference (χ2 = 1.8, P = .4) and intensity (χ = 0.2, P = .9). Modeling to predict outcomes correctly classified 69% of cases for pain interference and 88% of cases for pain intensity recovery trajectories using baseline scores.

CONCLUSION

People with CRPS, LBP, and CWP experience similar benefits following an IPMP. This supports the use of IPMPs for people with CRPS.

Effect of high-intensity laser therapy and mirror therapy on complex regional pain syndrome type I in the hand area: A randomized controlled trial

BACKGROUND

Complex regional pain syndrome type I (CRPS-I) is a painful condition with peripheral and central nervous system dysfunction, disproportionate inflammation, and the resultant muscle atrophy and restriction of motion. The use of high-intensity laser therapy (HILT) is being considered to reduce inflammation and neural and musculoskeletal pain. As maladaptive neuroplasticity occurs, peripheral treatment may not be enough and a combination of peripheral and centrally-focused interventions may be required.

PURPOSE

To explore the impact of HILT combined with mirror therapy (MT) on pain intensity, swelling, functional ability, range of motion (ROM), and electromyography (EMG) activity in CRPS-I.

STUDY DESIGN

Randomized, sham-controlled, single-blind clinical trial.

METHODS

Twenty-four CRPS-I patients were randomly assigned to two groups of HILT at 5 watts with an energy density of 20 J/cm², combined with MT and sham HILT and MT for six sessions. Pain was assessed by the Visual Analog Scale (VAS) before, the third session, and after the treatment. Hand swelling, function, and ROM were measured by a motion analysis system, and EMG of the hand muscles was also evaluated.

RESULTS

Pain significantly decreased in the HILT group. Compared to before treatment, the VAS mean difference in the third session was -2 ± 0.8 in the HILT group versus -0.4 ± 0.5 in the sham group (p < 0.001, ηp2 = 0.57). The VAS mean difference for before-after treatment was -4.2 ± 1.2 in the HILT group versus -1.4 ± 0.6 in the sham group (p < 0.001, ηp2 = 0.69). The other outcomes, like function, effusion, ROM, and EMG activity, were also in favor of the HILT group (p < 0.05).

CONCLUSIONS

Our study results offer conclusive evidence of pain reduction, a highly debilitating symptom in CRPS-I, even after the third HILT treatment session. Additionally, HILT effectively reduced swelling, improved performance, and enhanced muscle activity in CRPS-I.

How can Blood Flow Restriction Exercise be Utilised for the Management of Persistent Pain Following Complex Injuries in Military Personnel? A Narrative Review

BACKGROUND

Persistent pain is a complicated phenomenon associated with a wide array of complex pathologies and conditions (e.g., complex regional pain syndrome, non-freezing cold injury), leading to extensive disability and reduced physical function. Conventional resistance training is commonly contraindicated in load compromised and/or persistent pain populations, compromising rehabilitation progression and potentially leading to extensive pharmacological intervention, invasive procedures, and reduced occupational status. The management of persistent pain and utility of adjunct therapies has become a clinical and research priority within numerous healthcare settings, including defence medical services.

MAIN BODY

Blood flow restriction (BFR) exercise has demonstrated beneficial morphological and physiological adaptions in load-compromised populations, as well as being able to elicit acute hypoalgesia. The aims of this narrative review are to: (1) explore the use of BFR exercise to elicit hypoalgesia; (2) briefly review the mechanisms of BFR-induced hypoalgesia; (3) discuss potential implications and applications of BFR during the rehabilitation of complex conditions where persistent pain is the primary limiting factor to progress, within defence rehabilitation healthcare settings. The review found BFR application is a feasible intervention across numerous load-compromised clinical populations (e.g., post-surgical, post-traumatic osteoarthritis), and there is mechanistic rationale for use in persistent pain pathologies. Utilisation may also be pleiotropic in nature by ameliorating pathological changes while also modulating pain response. Numerous application methods (e.g., with aerobic exercise, passive application, or resistance training) allow practitioners to cater for specific limitations (e.g., passive, or contralateral application with kinesiophobia) in clinical populations. Additionally, the low-mechanical load nature of BFR exercise may allow for high-frequency use within residential military rehabilitation, providing a platform for conventional resistance training thereafter.

CONCLUSION

Future research needs to examine the differences in pain modulation between persistent pain and pain-free populations with BFR application, supporting the investigation of mechanisms for BFR-induced hypoalgesia, the dose-response relationship between BFR-exercise and pain modulation, and the efficacy and effectiveness of BFR application in complex musculoskeletal and persistent pain populations.

Efficacy of mirror neuron system-based therapy for rehabilitation of upper limb orthopedic conditions: A systematic review and meta-analysis

OBJECTIVE

The aim of this systematic review and meta-analysis is to assess the efficacy of mirror neuron system-based therapy for managing pain and improving motor and upper limb function in patients with upper limb orthopedic conditions.

LITERATURE SURVEY

Systematic bibliographical searches of the PubMed, SCOPUS, and CENTRAL registries and databases up to September 2023 were conducted to find randomized controlled trials (RCTs) assessing the efficacy of mirror neuron system-based therapy for rehabilitation of upper limb orthopedic conditions.

METHODOLOGY

Two reviewers assessed the RCTs using a Cochrane risk-of-bias tool and extracted data from studies with similar outcome measures in the domains of pain, motor function, or functional score, which were pooled into meta-analyses.

SYNTHESIS

The review included 13 studies to compare the efficacy of mirror neuron system-based therapy with that of conventional rehabilitation programs. The therapy reduced pain intensity (mean difference [MD] 2.04, 95% confidence interval [CI] 1.46-2.63) and kinesiophobia (MD 8.43, 95% CI 6.98 to 9.88), and increased grip strength (MD 1.86, 95% CI 0.28-3.45). The therapy also improved upper limb functional outcomes as assessed by the 30-item Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire score (MD 13.52, 95% CI 10.63-16.41). However, the outcomes as assessed by the 11-item QuickDASH questionnaire and the Shoulder Pain and Disability Index (SPADI) were not superior to conventional rehabilitation.

CONCLUSIONS

Mirror neuron system-based therapy for rehabilitation of upper limb orthopedic conditions may reduce pain intensity and kinesophobia, and improve grip strength and DASH scores compared with conventional rehabilitation programs. However, this interpretation is limited by the heterogeneity and various quality of the RCTs included in our meta-analysis.

Chronic post-ischemic pain (CPIP) a model of complex regional pain syndrome (CRPS-I): Role of oxidative stress and inflammation

Complex regional pain syndrome (CRPS) presents as a persistent and distressing pain condition often stemming from limb trauma or ischemia, manifesting as either CRPS-I (without initial nerve injury) or CRPS-II (accompanied by nerve injury). Despite its prevalence and significant impact on functionality and emotional well-being, standard treatments for CRPS remain elusive. The multifaceted nature of CRPS complicates the identification of its underlying mechanisms. In efforts to elucidate these mechanisms, researchers have turned to animal models such as chronic post-ischemic pain (CPIP), which mirrors the symptoms of CRPS-I. Various mechanisms have been proposed to underlie the acute and chronic pain experienced in CRPS-I, including oxidative stress and inflammation. Traditional treatment approaches often involve antidepressants, non-steroidal anti-inflammatory drugs (NSAIDs), and opioids. However, these methods frequently fall short of providing adequate relief. Accordingly, there is a growing interest in exploring alternative treatments, such as antioxidant supplementation, anti-inflammatory agents, and non-pharmacological interventions. Future research directions should focus on optimizing treatment strategies and addressing remaining gaps in knowledge to improve patient outcomes. This review aims to delve into the pathophysiological mechanisms implicated in the CPIP model, specifically focusing on oxidative stress and inflammation, with the ultimate goal of proposing innovative therapeutic strategies for alleviating the symptoms of CRPS-I.

Complex regional pain syndrome type II localized to the index finger. A case report translating scientific evidence into clinical practice

BACKGROUND

Complex regional pain syndrome type II (CRPS-II) is a rare condition associated with peripheral nervous system lesions. Its localized distribution in the fingers is unique, and its treatment is unclear.

CASE DESCRIPTION

A 56-year-old male presented to the emergency department with a saw-cut index finger injury with associated tendon and nerve injuries. After surgery, he was admitted to physical therapy (PT) with persistent pain, joint stiffness, allodynia, and trophic changes compatible with CRPS-II localized in the index finger. The diagnosis was confirmed after applying the Budapest Criteria, and PT was progressive and individualized according to the patient's needs, including graded motor imagery, mobilizations, exercises, and education.

OUTCOMES

After 12 weeks of PT, a clinically significant decrease in pain intensity and improvements in mobility and index finger and upper limb functionality was observed, reducing CRPS symptomatology.

DISCUSSION

This report provides information about a unique case of a localized form of CRPS-II. After reviewing the literature on clinical cases of both CRPS-II and localized forms of CRPS, we highlight that the clinical features of this patient and his positive therapeutic response support the importance of translating the scientific evidence on CRPS into clinical practice.

From Sudoscan to bedside: theory, modalities, and application of electrochemical skin conductance in medical diagnostics

The human body has two main types of sweat glands: apocrine and eccrine. Eccrine glands are widely distributed across the skin, including areas with hair. While the eccrine glands on palms and soles help improve grip, those on the rest of the body primarily aid in thermoregulation. Sudomotor function, which controls sweating, is regulated by the sympathetic division of the autonomic nervous system through cholinergic and adrenergic pathways. The activation of eccrine glands involves intricate processes, including neurotransmitter binding, ion channel modulation, and voltage generation. Sudoscan technology utilizes electrochemical skin conductance (ESC) to non-invasively measure sudomotor function. This method, which has been standardized for accuracy, has established normative benchmarks and has proven reliable across diverse populations. Sudoscan's diagnostic performance is comparable to invasive methods such as intraepidermal nerve fiber density testing, making it a valuable tool for diagnosing small fiber neuropathy. Moreover, it has been shown to correlate with corneal nerve fiber length, providing insights into various neuropathic conditions. Compared to traditional sudomotor function tests, Sudoscan proves superior in terms of its accessibility, simplicity, and reliability, with the potential to replace or complement existing diagnostic methods. It is important to differentiate ESC, as measured by Sudoscan, from other skin conductance measures, such as galvanic skin response (GSR) or electrodermal activity (EDA). Although these methods share a common physiological principle, ESC is specifically designed for diagnosing sudomotor function, unlike GSR/EDA, which is typically used for continuous monitoring. Sudoscan's success has led to its integration into consumer health devices, such as the BodyScan from Withings, showcasing its versatility beyond clinical settings. Future research may explore ESC applications in diverse medical fields, leveraging real-world data from integrated consumer devices. Collaborative efforts between researchers and engineers promise to offer new insights into sudomotor function and its implications for broader health monitoring. This study provides a comprehensive overview of ESC, including topics such as eccrine gland physiology, sudomotor function, Sudoscan technology, normative benchmarks, diagnostic comparisons, and potential future applications.

Complex Regional Pain Syndrome: a cross-sectional study of physical symptoms, disability, and psychological health in long term

Introduction

Knowledge about long-time residual symptoms, disabilities, and psychological health in complex regional pain syndrome (CRPS) is limited.

Objectives

The aim was to evaluate outcome, focusing on physical symptoms, disability, and psychological health, in individuals with CRPS through a cross-sectional survey study.

Methods

Individuals with a confirmed diagnosis of CRPS were identified through medical charts and sent validated survey forms (Disabilities of the Arm, Shoulder and Hand-Quick version, Specific Hand Surgery Questionnaire-8 questions, EuroQol 5 Dimensions 3 levels, Life Satisfaction Questionnaire-11, Hospital Anxiety and Depression Scale, Pain Catastrophizing Scale, and Sense of Coherence-29) and complementary questions.

Results

Responders (response rate: 99/238, 42%; CRPS type 1: 72%; CRPS type 2: 28%; time since diagnosis median: 59 [34-94] months) reported remaining symptoms and disability (Disabilities of the Arm, Shoulder and Hand-Quick version score: 45 [20-70]) and more improvement in type 1 than in type 2. Only 9% of individuals with CRPS reported no residual pain or discomfort. Approximately 60% had problems in daily activities, 49% had sleeping problems, and 90% experienced moderate-extreme pain with 23% still on sick leave. The Hospital Anxiety and Depression Scale survey revealed significantly higher scores than a Swedish reference population. Individuals with a low Sense of Coherence and high pain catastrophizing had worse disability and were less satisfied with their lives and physical and psychological health. A lower level of education and more anxiety were associated with worsened disability over time.

Conclusion

Individuals with CRPS suffer in the long term from pain, sleeping problems, and limitations in daily activities with occurrence of anxiety and depression, resulting in dissatisfaction with many aspects of their lives. A low Sense of Coherence and high pain catastrophizing are associated with a worse outcome. Biopsychosocial aspects should be addressed in clinical practice.

Bone Scintigraphy in 2 Cases of Complex Regional Pain Syndrome

ABSTRACT

A 59-year-old woman was presented to the outpatient clinic with persistent pain after a hyperextension/inversion trauma of the ankle. Six months after the incident, a 3-phase bone scan was performed. A second patient, a 54-year-old man, was referred for a 3-phase bone scan 2 months after his right hand was twisted while using a drill. In both patients, scintigraphy showed diffuse increased uptake in the affected limb in all 3 phases. The x-rays of the affected limbs showed osteopenia. These findings are consistent with (early phase) complex regional pain syndrome.

Effects of mirror therapy in post-traumatic complex regional pain syndrome type-1: a randomized controlled study

OBJECTIVE

To investigate the effects of mirror therapy applied in addition to routine rehabilitation on clinical outcomes in post-traumatic complex regional pain syndrome type 1.

DESIGN

Single-blind randomized controlled trial.

SUBJECTS

Patients with trauma-induced complex regional pain syndrome type 1 of the hand receiving outpatient rehabilitation.

METHODS

Patients were randomized into mirror therapy and control groups. All patients received routine physical therapy and rehabilitation for 20 sessions (5 sessions/week, for 4 weeks). The mirror group received additional mirror therapy at each session. The primary outcome was pain intensity by numeric rating scale. Secondary outcomes were grip/pinch strength, hand/wrist circumference, dexterity, hand activities, and health-related quality of life. All assessments were performed before and immediately after the treatment, and 4 weeks later at follow-up.

RESULTS

Forty patients were enrolled, 20 in each group. Both groups revealed statistically significant improvements from therapy regarding pain, grip/pinch strength, wrist circumference, dexterity, and hand activities (p <  0.05). When groups were compared regarding the improvements in assessment parameters, no statistically significant difference was found between the 2 groups in any of the outcomes (p > 0.05).

CONCLUSION

Mirror therapy applied in addition to routine therapy in post-traumatic complex regional pain syndrome type 1 did not provide extra benefit to the improvement of pain, function, and other clinical outcomes.

Effect duration of lumbar sympathetic ganglion neurolysis in patients with complex regional pain syndrome: a prospective observational study

Lumbar sympathetic ganglion neurolysis (LSGN) has been used for long-term pain relief in patients with complex regional pain syndrome (CRPS). However, the actual effect duration of LSGN has not been accurately measured. This prospective observational study measured the effect duration of LSGN in CRPS patients and investigated the relationship between temperature change and pain relief. After performing LSGN, the skin temperatures of both the maximum pain site and the plantar area in the affected and unaffected limbs were measured by infrared thermography, and pain intensity was assessed before and at 2 weeks, 1 month, and 3 months. The median time to return to baseline temperature was calculated using survival analysis. The skin temperature increased significantly at all-time points relative to baseline in both regions (maximum pain site: 1.4 °C ± 1.0 °C, plantar region: 1.28 °C ± 0.8 °C, all P < 0.001). The median time to return to baseline temperature was 12 weeks (95% confidence interval [CI] 7.7-16.3) at the maximum pain site and 12 weeks (95% CI 9.4-14.6) at the plantar area. Pain intensity decreased significantly relative to baseline, at all-time points after LSGN. In conclusion, the median duration of the LSGN is estimated to be 12 weeks.

Effectiveness of motor imagery in complex regional pain syndrome: A systematic review with meta-analysis

OBJECTIVE

The purpose of this study was to determine the effects of motor imagery (MI) on pain intensity and disability in individuals with complex regional pain syndrome (CRPS).

METHODS

A systematic search was conducted in various electronic databases to identify all relevant studies: PubMed, CINAHL, WOS, PEDro, CENTRAL, and Scopus. Randomized controlled trials assessing the effects of MI in individuals with CRPS were included. The risk of bias was assessed with the Cochrane Risk of Bias tool, the methodological quality was evaluated using PEDro scale, and the level of evidence was reported according to the GRADE. Between-groups standardized mean differences (SMD) were calculated.

RESULTS

Six studies were included. The meta-analysis found moderate-quality evidence that MI improves pain intensity and related disability as immediate (pain: SMD -1.07, 95% CI: -1.53 to -0.60; disability: SMD 1.05, 95% CI: 0.59 to 1.51), short-term (pain: SMD -1.28, 95% CI: -2.14 to -0.42; disability: SMD 1.37; 95% CI: 0.16 to 2.58), and long-term effects (pain: SMD -1.18; 95% CI: -1.89 to -0.46; disability: SMD 1.18; 95% CI: 0.46 to 1.89), as compared with a comparison group. The risk of bias of the trials was relatively low, but the imprecision of the results downgraded the level of evidence.

CONCLUSIONS

Moderate-quality evidence suggests a positive effect of MI for improving pain intensity and disability immediately after and at short-term in individuals with CRPS.

Innovations in Stroke Recovery and Rehabilitation: Poststroke Pain

Pain can be a significant barrier to a stroke survivors' functional recovery and can also lead to a decreased quality of life. Common pain conditions after stroke include headache, musculoskeletal pain, spasticity-related pain, complex regional pain syndrome, and central poststroke pain. This review investigates the evidence of diagnostic and management guidelines for various pain syndromes after stroke and identifies opportunities for future research to advance the field of poststroke pain.

Patients' experiences of treatment-relevant processes in multimodal pain rehabilitation for severe complex regional pain syndrome - a qualitative study

PURPOSE

Complex regional pain syndrome (CRPS) is a longstanding condition with spontaneous and evoked pain, that usually occurs in an upper or lower extremity. Although it often resolves within the first year, it may for a minority progress to a chronic and occasionally severely disabling condition. The aim of this study was to explore patients' experiences and perceived effects of a specific treatment, designed for patients with severe and highly disabling CRPS, in order to identify possible treatment-relevant processes.

METHODS

The method used was a qualitative design, using semi-structured interviews with open-ended questions to capture participants' experiences and perceptions. Ten interviews were analyzed using applied thematic analysis.

RESULTS

Despite the fact that participants had a severe conditions, including nerve damage and a long duration of illness, they reported having been helped to increase flexible persistence, reduce fear and avoidance, and improve connections. This helped participants to significant improvements in daily life functioning.

CONCLUSIONS

The participants described distinct possible treatment-relevant processes leading to a substantial improvement in everyday life. The results imply that there is hope for this group that has been severely disabled for many years. This may help guide future clinical treatment trials.

Therapeutic management of the painful nerve: a narrative review of common rehabilitation interventions

There are many ways that rehabilitation therapists, including occupational and physical therapists, treat nerve-related pain. Commonly used interventions include neurodynamic treatment, pain neuroscience education, desensitization, exercise, physical agent modalities, mirror box therapy, and Kinesio taping. Despite common practice and anecdotal support, it can be challenging to determine the appropriate intervention for each patient. In this article, each of these treatment approaches is discussed, including indicated pain phenotypes and diagnoses, timing, efficacy, mechanism, contraindications, and limitations.

Rehabilitation Interventions for Complex Regional Pain Syndrome: An Overview of Systematic Reviews

OBJECTIVES

An increasing number of systematic reviews have been conducted on various conservative management of complex regional pain syndrome (CRPS) targeting different rehabilitation interventions and objectives. The intent of this article was to summarize and critically appraise the body of evidence on conservative management of the CRPS and to provide an overall picture of the current state of the literature.

METHODS

This study was an overview of systematic reviews on conservative treatments for CRPS. We conducted a literature search from inception to January 2023 in the following databases: Embase, Medline, CINAHL, Google Scholar, Cochrane Library, and Physiotherapy Evidence Database (PEDro). Two independent reviewers conducted study screening, data extraction, and methodological quality assessment (using AMSTAR-2). Qualitative synthesis was the preferred method for reporting the findings of our review. We calculated the corrected covered area index to account for the proportion of overlapping primary studies that were included in multiple reviews.

RESULT

We identified 214 articles, and a total of 9 systematic reviews of randomized controlled trials were eligible for inclusion. Pain and disability were the most common outcomes evaluated in the reviews. There were 6 (6/9; 66%) high-quality, 2 (2/9; 22%) moderate-quality, and 1 critically low-quality systematic review (1/9;11%), with the quality of the included trials ranging from very low to high. There was a large overlap across primary studies that were included in the systematic reviews (corrected covered area=23%). The findings of high-quality reviews support the effectiveness of mirror therapy (MT) and graded motor imagery (GMI) programs on pain and disability improvement in CRPS patients. The large effect size was reported for the effectiveness of MT on pain and disability (SMD:1.88 (95% CI: 0.73-3.02) and 1.30 (95% CI: 0.11-2.49), respectively) and the effectiveness of GMI program (GMIP) on pain and disability improvement (SMD: 1.36 (95% CI: 0.75-1.96) and 1.64 (95% CI: 0.53-2.74), respectively).

DISCUSSION

The evidence is in favor of adopting movement representation techniques, such as MT and GMI programs, for the treatment of pain and disability in patients with CRPS. However, this is based on a small body of primary evidence, and more research is required to generate conclusions. Overall, the evidence is not comprehensive or of sufficient quality to make definitive recommendations about the effectiveness of other rehabilitation interventions in improving pain and disability.