Risk factors for complex regional pain syndrome in patients with surgically treated traumatic injuries attending hand therapy

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.

Experiences of diagnosis and treatment for upper limb Complex Regional Pain Syndrome: a qualitative analysis

INTRODUCTION

Complex Regional Pain Syndrome (CRPS) most frequently affects the upper limb, with high associated disability. Delays to diagnosis and appropriate treatment can adversely impact prognosis and quality of life, but little is known about the healthcare experiences of people with CRPS. This study aimed to explore lived experiences of diagnosis and treatment for people with upper limb CRPS.

METHODS

Participants were recruited through online support groups and multiple public and private healthcare settings in the Greater Wellington Region, New Zealand. Semi-structured interviews were conducted with participants who had experienced upper limb CRPS for more than three months and less than three years. Interviews were transcribed verbatim and analysed using reflexive thematic analysis.

RESULTS

Thirteen participants (11 female, 2 male) aged between 43 and 68 years were interviewed. Duration of CRPS ranged from 7 months to 2.5 years. Five themes were identified. Participants initially engaged in healthcare out of a desire to return to being the person they were before having CRPS. Three interacting experiences epitomised the overall healthcare experience: (1) not knowing what is going on, (2) not being taken seriously, and (3) healthcare as adding another layer of load. Meanwhile, participants used multiple approaches in an attempt to not let CRPS stop them from continuing to live their lives.

CONCLUSIONS

Participants in this study felt that credible information, validation, and simplification from healthcare providers and systems would support their process of navigating towards a meaningful life and self-concept in the presence of CRPS.

Interventions for treating pain and disability in adults with complex regional pain syndrome- an overview of systematic reviews

BACKGROUND

Complex regional pain syndrome (CRPS) is a chronic pain condition that usually occurs in a limb following trauma or surgery. It is characterised by persisting pain that is disproportionate in magnitude or duration to the typical course of pain after similar injury. There is currently no consensus regarding the optimal management of CRPS, although a broad range of interventions have been described and are commonly used. This is the first update of the original Cochrane review published in Issue 4, 2013.

OBJECTIVES

To summarise the evidence from Cochrane and non-Cochrane systematic reviews of the efficacy, effectiveness, and safety of any intervention used to reduce pain, disability, or both, in adults with CRPS.

METHODS

We identified Cochrane reviews and non-Cochrane reviews through a systematic search of Ovid MEDLINE, Ovid Embase, Cochrane Database of Systematic Reviews, CINAHL, PEDro, LILACS and Epistemonikos from inception to October 2022, with no language restrictions. We included systematic reviews of randomised controlled trials that included adults (≥18 years) diagnosed with CRPS, using any diagnostic criteria.  Two overview authors independently assessed eligibility, extracted data, and assessed the quality of the reviews and certainty of the evidence using the AMSTAR 2 and GRADE tools respectively. We extracted data for the primary outcomes pain, disability and adverse events, and the secondary outcomes quality of life, emotional well-being, and participants' ratings of satisfaction or improvement with treatment.  MAIN RESULTS: We included six Cochrane and 13 non-Cochrane systematic reviews in the previous version of this overview and five Cochrane and 12 non-Cochrane reviews in the current version. Using the AMSTAR 2 tool, we judged Cochrane reviews to have higher methodological quality than non-Cochrane reviews. The studies in the included reviews were typically small and mostly at high risk of bias or of low methodological quality. We found no high-certainty evidence for any comparison.  There was low-certainty evidence that bisphosphonates may reduce pain intensity post-intervention (standardised mean difference (SMD) -2.6, 95% confidence interval (CI) -1.8 to -3.4, P = 0.001; I2 = 81%; 4 trials, n = 181) and moderate-certainty evidence that they are probably associated with increased adverse events of any nature (risk ratio (RR) 2.10, 95% CI 1.27 to 3.47; number needed to treat for an additional harmful outcome (NNTH) 4.6, 95% CI 2.4 to 168.0; 4 trials, n = 181).  There was moderate-certainty evidence that lidocaine local anaesthetic sympathetic blockade probably does not reduce pain intensity compared with placebo, and low-certainty evidence that it may not reduce pain intensity compared with ultrasound of the stellate ganglion. No effect size was reported for either comparison. There was low-certainty evidence that topical dimethyl sulfoxide may not reduce pain intensity compared with oral N-acetylcysteine, but no effect size was reported. There was low-certainty evidence that continuous bupivacaine brachial plexus block may reduce pain intensity compared with continuous bupivacaine stellate ganglion block, but no effect size was reported. For a wide range of other commonly used interventions, the certainty in the evidence was very low and provides insufficient evidence to either support or refute their use. Comparisons with low- and very low-certainty evidence should be treated with substantial caution. We did not identify any RCT evidence for routinely used pharmacological interventions for CRPS such as tricyclic antidepressants or opioids.

AUTHORS' CONCLUSIONS

Despite a considerable increase in included evidence compared with the previous version of this overview, we identified no high-certainty evidence for the effectiveness of any therapy for CRPS. Until larger, high-quality trials are undertaken, formulating an evidence-based approach to managing CRPS will remain difficult. Current non-Cochrane systematic reviews of interventions for CRPS are of low methodological quality and should not be relied upon to provide an accurate and comprehensive summary of the evidence.

Perception of Heaviness Induced by Sensorimotor Incongruence Is Associated with Pain Prognosis: A Pilot Study

Background. Patients with chronic musculoskeletal pain experience not only pain but also abnormal body perception. Such abnormal body perception has been reported to be caused by incongruence between motor intentions and sensory feedback (i.e., sensorimotor incongruence). However, the influence of abnormal body perception with sensorimotor incongruence on pain prognosis in musculoskeletal pain patients has not been investigated. Objective. We aimed at clarifying the influence of abnormal body perception on pain prognosis using an experimental procedure for inducing sensorimotor incongruence in patients with musculoskeletal pain. Methods. We recruited 18 patients within 2 months after limb fracture or ligament injury. In the experiment, patients sat with the intact upper or lower limb reflected in a large mirror aligned with the sagittal plane. A motor task was performed for 20 seconds in each of the congruent and incongruent conditions. In the congruent condition, patients were asked to perform flexion-extension movements with the intact and affected limbs in-phase, while observing the intact limb in the mirror. In the incongruent condition, patients were asked to perform flexion-extension movements antiphase, while observing the intact limb in the mirror. After performing the congruent and incongruent conditions, patients were asked to complete a questionnaire about abnormal body perception. These procedures were conducted within 2 months after the fracture (first), 2 weeks after the first measurement (second), and 4 weeks (third) after the first measurement. Results. Pain, heaviness, and peculiarity were more likely to be experienced in incongruent conditions. Additionally, structural equation modeling indicated that heaviness at the first time point predicted the pain intensity at the second and third time points. Conclusions. Heaviness caused by sensorimotor incongruence may predict pain prognosis in patients with musculoskeletal pain after one month.

Biological and psychological early prognostic factors in complex regional pain syndrome: A systematic review

BACKGROUND AND OBJECTIVE

Several risk factors for the onset of CRPS have been found, but evidence for prognostic factors associated with the progression of this condition remains sparse. However, the detection and management of these factors are necessary to design secondary prevention strategies. The objective of this systematic review was to identify prognostic factors in adult individuals with early CRPS.

DATABASE AND DATA TREATMENT

PubMed, Embase, PsycINFO, Cochrane Library and Scopus, were published between January 1990 and November 2021. Two independent investigators selected cross-sectional and longitudinal studies looking at early (<12 weeks from onset) prognostic factors for pain, CRPS severity score, disability, return to work, or quality of life. The quality in prognostic studies (QUIPS) tool was used to assess the risk of bias. A qualitative meta-synthesis was performed.

RESULTS

Out of 4652 different articles, six studies met the inclusion criteria. We identified 21 early factors associated with a poorer prognosis in type I CRPS. We found moderate evidence to support six of them: higher pain intensity, self-rated disability, anxiety, pain-related fear, being a female and high-energy triggering event. Only two studies had an overall low risk of bias.

CONCLUSIONS

This study showed an important lack of information on early prognostic factors in CRPS. Only one article investigated the link with psychological characteristics. There is a crucial need for larger studies, with a well-defined population using validated measures.

SIGNIFICANCE

This systematic review highlights the lack of knowledge about early prognostic factors in CRPS. A few putative prognostic factors were identified. Most of the moderate evidence is related to a single cohort. Future research is required to find out which patients are vulnerable to chronification.

Factors associated with disability and pain intensity in patients with complex regional pain syndrome

PURPOSE

To examine the associations between psychological factors (pain catastrophizing, pain-related anxiety, and fear of pain) and level of pain and disability in patients with complex regional pain syndrome (CRPS).

METHODS

One hundred and two patients with CRPS were recruited from tertiary care centers with the different upper limb injuries were evaluated for pain, disability, and psychological factors. Patients completed the Disabilities of the Arm, Shoulder, and Hand (DASH) Questionnaire, Patient Rated Wrist Evaluation (PRWE), Pain Catastrophizing Scale (PCS), Tampa Scale of Kinesiophobia (TSK-11), and Depression, Anxiety, and Stress Scale (DASS). The associations of pain and disability with presence of these behavioral and mental health factors were examined using bivariate and multivariable analyses. These models were adjusted for age, sex, injured dominant hand, and previous surgery.

RESULTS

A higher pain catastrophizing score (β = 0.55, p = 0.00) was associated with greater disability. A higher pain catastrophizing score (β = 0.35, p = 0.001) and female gender (β = 0.24, p = 0.01) were associated with greater pain at rest (PAR). A higher pain catastrophizing score and having a surgical history were associated with greater pain with movement (β = 0.25, p = 0.02). Scores of ≥18.5 in PCS, ≥57.5 on TSK, and ≥15.5 on DASS were associated with higher risk of experiencing pain and disability.

CONCLUSIONS

Pain catastrophizing, female sex, and surgical intervention are associated with poor outcomes. Physiologic, psychological factors, and treatment factors interact to influence outcomes. The results of this study further validate the associations of chronic pain and disability with pain catastrophizing in patients with CRPS. The novel finding of this study is introducing cut-off scores for TSK, PCS, and DASS as a screening tool to predict pain, functional limitations.Implication for rehabilitationPain catastrophizing has a vital role in the magnitude of disability and pain in patients with CRPS.The novel finding of this paper was the cut-off scores on the psychological evaluations that can enable using them as screening tool for bad outcomes in patients with CRPS.Cut off scores from different psychological evaluations can be used as a yellow flag for clinician's for detecting patients with increased risk of pain and disability.The identification of a cut-off can also have implications for implementing change in clinical practice by identifying the need for early and intensive interventions.

Preoperative Predictors of Complex Regional Pain Syndrome Outcomes in the 6 Months Following Total Knee Arthroplasty

This prospective observational study evaluated preoperative predictors of complex regional pain syndrome (CRPS) outcomes in the 6 months following total knee arthroplasty (TKA). Participants were n = 110 osteoarthritis patients (64.5% female) undergoing unilateral TKA with no prior CRPS history. Domains of negative affect (depression, anxiety, catastrophizing), pain (intensity, widespread pain, temporal summation of pain [TSP]), pain interference, sleep disturbance, and pro-inflammatory status (tumor necrosis factor-alpha [TNF-a]) were assessed preoperatively. CRPS outcomes at 6-week and 6-month follow-up included the continuous CRPS Severity Score (CSS) and dichotomous CRPS diagnoses (2012 IASP criteria). At 6 months, 12.7% of participants met CRPS criteria, exhibiting a "warm CRPS" phenotype. Six-week CSS scores were predicted by greater preoperative depression, anxiety, catastrophizing, TSP, pain intensity, sleep disturbance, and TNF-a (P's < .05). Provisional CRPS diagnosis at 6 weeks was predicted by higher preoperative TSP, sleep disturbance, and TNF-a (P's < .05). CSS scores at 6 months were predicted by more widespread and intense preoperative pain, and higher preoperative TSP, pain interference, and TNF-a (P's < .01). CRPS diagnosis at 6 months was predicted only by more widespread and intense pain preoperatively (P's < .05). Risk for CRPS following TKA appears to involve preoperative central sensitization and inflammatory mechanisms. Preoperative negative affect is unlikely to directly influence long-term CRPS risk. PERSPECTIVE: This article identifies preoperative predictors of CRPS features at 6 months following total knee arthroplasty, including more widespread pain and higher pain intensity, temporal summation of pain, pain interference, and tumor necrosis factor-alpha levels. Findings suggest the importance of central sensitization and inflammatory mechanisms in CRPS risk following tissue trauma.

Complete Occlusion of Radial and Ulnar Arteries Following Hand Crush Injury with Multiple Carpometacarpal Joint Fracture-Dislocations

Multiple dorsal fracture-dislocations of the carpometacarpal joints (CMCJ) occur from very high-energy trauma and are often associated with soft tissue injury or ischaemia. We report a 54-year-old male manual worker and a smoker who presented to the emergency room with history of compression of his right hand in a press machine. Radiographs showed dorsal fracture-dislocations of the scapho-trapezio-trapezoidal and third to fifth CMCJ's. Despite emergent Guyon canal and carpal tunnel release and closed reduction and pinning, skin pallor persisted in all digits. Brachial angiography revealed total occlusion of the radial and ulnar arteries and loss of the palmar arch at the level of the fracture. Heparin and Alprostadil were injected directly. On follow-up angiography three weeks later, the vessels were still occluded and collaterals provided digital circulation. Although digital sensations recovered, cold intolerance and stiffness resulted in a poor functional outcome. Level of Evidence: Level V (Therapeutic).

Analysis of the Experiences of Adults with Complex Regional Pain Syndrome

Complex regional pain syndrome is a rare, intractable disease causing chronic pain. For improved subjective and personal experience, an individualized treatment approach based on a thorough understanding of the patient’s perceptions is required for pain management. In this study, we examined the experiences and challenges of 11 Korean patients diagnosed with complex regional pain syndrome. The patients described their experiences during in-depth, face-to-face interviews, and data were subjected to a thematic analysis. We identified the following three main themes: “my own non-stereotyped pain,” “complex emotions caused by pain,” and “a careful life endured alone.” Enduring pain alone was difficult, and the lack of support from family members, caregivers, or society amplified the patients’ hardships. As these patients often felt alone when coping with internal difficulties, including pain, they frequently coped through self-management of the condition. The importance of offering realistic support to complex regional pain syndrome patients is underscored via a multifaceted approach and may aid in the development of educational programs for medical personnel, families, and caregivers of these patients.

Hyperbaric oxygen treatment in recurrent development of complex regional pain syndrome: A case report

A broad spectrum of conditions including neuropathic pain, complex regional pain syndrome (CRPS) and fibromyalgia, have been implicated as causes of chronic pain. There is a need for new and effective treatments that patients can tolerate without significant adverse effects. One potential intervention is hyperbaric oxygen treatment (HBOT). The case reported here is unique in describing repeated HBOT in a patient who developed recurrent post-traumatic CRPS of the lower as well as the upper limbs. In the first event, two months after distortion and abruption of the external right ankle, the patient suffered leg pain, oedema formation, mild hyperaemia, limited mobility of the ankle and CRPS Type 1. In the second event, the same patient suffered fracture-dislocation of the distal radius 1.5 years after the first injury. After the plaster cast was removed the patient developed pain, warmth, colour changes, oedema formation and limited wrist mobility with CRPS Type 1. Pharmacological treatment as well as HBOT were used with significant improvement of functional outcome in both cases. Some studies suggest that patients with a history of CRPS are more likely to develop secondary CRPS compared to the rates reported in the literature among the general population. Patients with a history of CRPS should be counselled that they may be at risk for developing secondary CRPS if they undergo surgery or sustain trauma to another extremity.

Subliminal (latent) processing of pain and its evolution to conscious awareness

By unconscious or covert processing of pain we refer to nascent interactions that affect the eventual deliverance of pain awareness. Thus, internal processes (viz., repeated nociceptive events, inflammatory kindling, reorganization of brain networks, genetic) or external processes (viz., environment, socioeconomic levels, modulation of epigenetic status) contribute to enhancing or inhibiting the presentation of pain awareness. Here we put forward the notion that for many patients, ongoing sub-conscious changes in brain function are significant players in the eventual manifestation of chronic pain. In this review, we provide clinical examples of nascent or what we term pre-pain processes and the neurobiological mechanisms of how these changes may contribute to pain, but also potential opportunities to define the process for early therapeutic interventions.

Neurogenic Edema from Complex Regional Pain Syndrome Resulting in Fulminant Infection Necessitating Below Elbow Amputation

We report a case of severe upper extremity complex regional pain syndrome type 1 (CRPS-1) and neurogenic edema that ultimately led to a medically necessary below-elbow amputation. The patient presented with a history of remote bilateral carpal tunnel release complicated by debilitating and recalcitrant bilateral CRPS-1. Following years of severe neurogenic edema of the left upper extremity, the patient had full-thickness skin sloughing on the dorsum of her hand due to massive edema. This subsequently led to maggot infestation of the soft tissues of the left hand ultimately necessitating amputation. We present the case as an illustration of an extreme case of neurogenic edema, a potential physical manifestation of CRPS-1. The case presented discusses upper extremity amputation as an end treatment option for CRPS-1, though in this case amputation was primarily indicated secondary to medical necessity.