Complex regional pain syndrome: a review

Effects of Mecobalamin on the Functional Outcomes of Complex Regional Pain Syndrome Type 1 of the Foot and Ankle

BACKGROUND

Because of the unclear pathophysiology and the lack of consensus on the gold standard treatment of complex regional pain syndrome (CRPS), management requires a multidisciplinary approach, with the use of various treatment modalities. Nonetheless, no studies have ever been conducted to uncover the potential of mecobalamin as a treatment for CRPS type 1. Hence, the aim of this clinical trial was to evaluate the effects of mecobalamin on the functional outcomes of patients with CRPS type 1 of the foot and ankle, the total amount of pregabalin ingested, and the duration of pregabalin use in each patient.

METHODS

Forty-seven patients diagnosed with acute CRPS type 1 of the foot and ankle were recruited. Patients were randomly allocated into a control group (23 patients) and a mecobalamin group (24 patients), both receiving similar pain control medications and rehabilitation programs. Three divided doses of mecobalamin 1.5 mg/d were provided to the mecobalamin group for the first 3 months, whereas a placebo was administered to the control group. Data were collected from the pretreatment period, and from 1, 3, 6, and 12 months following the treatment.

RESULTS

Both groups had similar demographics. The mean Foot and Ankle Ability Measure (FAAM) activities of daily living (ADL) and FAAM-sport scores in the mecobalamin group at 3 months were 74.5 ± 17.9 and 56.3 ± 22.9, whereas the mean FAAM-ADL and FAAM-sport scores in the placebo group at 3 months were 62.2.5 ± 15.2 and 43.4 ± 14.9, respectively (P < .05). The 36-Item Short Form Health Survey (SF-36) mental health subscale after 3 months were 83.3 ± 9.5 points and 75.8 ± 12.6 points in the mecobalamin and placebo group, respectively (P < .05). However, at other time points of assessment (1, 6, and 12 months), the improvement in symptoms was not distinguishable between the 2 groups. Both the amount and duration of total pregabalin required to achieve similar improvements in pain scores were significantly lower in the mecobalamin group than the control group.

CONCLUSION

This small study revealed an improvement of the functional outcomes in patients with CRPS type 1 of the foot and ankle who received mecobalamin instead of a placebo at 3 months that was not sustained at 6 and 12 months. We identified an average 39% total reduction in the amount of total pregabalin used in the mecobalamin group in the first 12 months.

Efficacy of vitamin C supplementation in preventing and treating complex regional pain syndrome type I (CRPS-I) in Orthopedic patients: A systematic review and meta-analysis

AIM

Complex regional pain syndrome type I (CRPS-I) is a specific type of persistent pain which is often caused by fracture and surgery. There is no effective curative therapy available. However some studies have indicated that Vitamin C (VC) can reduce the incidence of CRPS-I. This study's objective is to investigate the effectiveness VC in preventing and treating CRPS-I.

DESIGN

An Systematic review and Meta-analysis was done.

DATA SOURCES

Primary research studies from PubMed, Scopus, Web of Science, ProQuest, Embase database, and Cochran Library, and Google Scholar were reviewed. This search was conducted until March 27, 2024. This study was conducted without any language, place, and time restrictions. Study results were meta-analyzed with using effect sizes. To evaluate heterogeneity, we employed the Cochrane Q test and the I2 index.

RESULTS

In our systematic review, 3947 articles were initially identified, with 3939 excluded for not meeting inclusion criteria, resulting in 8 studies being critically evaluated using Cochran's risk of bias checklist. The meta-analysis revealed that VC supplementation have effect on reducing CRPS-I post-limb surgery but this result shows that the pooled effect size is not statistically significant. The heterogeneity of the studies was low (I2 = 26.28%, p = 0.22). Publication bias was detected, indicating asymmetry in the funnel plot.

CONCLUSION

The results of our study showed the positive effect of VC supplementation in reducing the prevalence of CRPS-I after limb surgery.

Patients With Preexisting Anxiety and Mood Disorders Are More Likely to Develop Complex Regional Pain Syndrome After Fractures

BACKGROUND

Complex regional pain syndrome (CRPS) is a multifactorial condition that may affect patients who sustain a fracture in the upper and lower extremities. Prior investigations have formed a foundation for exploring a possible association between psychiatric disorders and the development of CRPS; however, current studies are conflicted regarding the existence and temporality of a relationship between psychiatric disorders and the potential development of CRPS.

QUESTIONS/PURPOSES

(1) Are patients with preexisting anxiety and mood disorders (AMDs) at increased risk of receiving a diagnosis of CRPS after upper or lower extremity fractures? (2) Are patients with preexisting AMDs at increased risk of being diagnosed with CRPS after surgical fixation of their fracture?

METHODS

A large, retrospective cohort study was conducted using the TriNetX electronic medical record platform, which contains data from more than 100 million patients. This platform gathers data from healthcare organizations in the United States and Europe and collects comprehensive data over time that includes temporality rather than simply the binary presence or absence of conditions. The cohort included 760,595 patients older than 18 years with upper or lower extremity fractures between 2003 and 2022. Included patients had a minimum 1-year follow-up. We defined AMDs as any diagnosis of anxiety, depressive episode or disorder, a manic episode, or bipolar disorder. Patients with polytrauma or concurrent upper and lower extremity fractures were excluded to reduce confounders. CRPS I diagnosis was identified via International Classification of Diseases, Tenth Edition codes. Propensity score matching was performed to balance cohorts based on age, gender, and race. Hazard ratios and Aalen-Johansen cumulative incidence curves for the diagnosis of CRPS were calculated for patients with and without AMD diagnoses before sustaining a fracture. A subanalysis was performed in which we examined individuals in the upper and lower extremity fracture cohorts who underwent surgical treatment.

RESULTS

Patients with preexisting AMDs were at a higher risk of experiencing CRPS I than patients without AMDs were (upper extremity: HR 1.8 [95% CI 1.7 to 1.9]; p < 0.01, lower extremity: HR 2.2 [95% CI 2.0 to 2.3]; p < 0.01). Similarly, patients with preexisting AMDs were at higher risk of experiencing CRPS I after fracture fixation than patients without AMDs were (upper extremity: HR 1.3 [95% CI 1.2 to 1.5]; p < 0.01, lower extremity: HR 2.3 [95% CI 2.1 to 2.5]; p < 0.01).

CONCLUSION

Awareness of the relationship between AMDs and CRPS I will direct future research about the development of this condition and associated neurologic changes. Additionally, surgeons can address AMDs perioperatively and arrange for the treatment of these AMDs with psychiatrists, neurologists, or social work, as appropriate. Accordingly, patients with AMDs should also be made aware of the inherent risk of CRPS I after an upper or lower extremity fracture to comprehensively educate and care for this at-risk patient population.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Prevalence and predisposing factors of post-stroke complex regional pain syndrome: Retrospective case-control study

INTRODUCTION

Poststroke complex regional pain syndrome (CRPS) is an important complication in stroke survivors. The identification of factors associated with post-stroke CRPS is important for preventive measures and early diagnosis.

METHODS

A total of 141 first-ever stroke survivors in the subacute stage were retrospectively analyzed. Demographic data, diagnosis time, duration of hospitalization, location of brain lesion, etiology, comorbidities, and blood test findings were investigated. Clinical data included Medical Research Council (MRC) grade, Fugl-Meyer assessment (FMA), National Institute for Health Stroke Scale (NIHSS), Berg Balance Scale (BBS).

RESULTS

Among 141 patients with subacute stroke, 22 were diagnosed with CRPS, with a prevalence of 15.6 %. The mean time to diagnosis was 38.6 (±16.5) days. The prevalence according to the degree of paralysis was 33.3 % in MRC grades 0 and 1, 8.6 % in grade 2, and 0 % in grade 3 or higher. The incidence rates within 1 month after stroke were 1.42 % and 22.47 % between 1 and 3 months after stroke, respectively. The independent risk factors for CRPS were hospitalization duration and FMA, NIHSS, and BBS scores. The sensitivity and specificity of the NIHSS score for predicting post-stroke CRPS were 86.4 % and 59.7 %, respectively, with an optimal cutoff value of 7.5.

CONCLUSIONS

CRPS of the affected upper limb in stroke patients is associated with stroke severity, including paralysis, and the incidence increases over time during the subacute phase. Additionally, having sufficient strength to move through a full range of motion against gravity had a protective effect against CRPS.

Complex regional pain syndrome following vascular access creation for hemodialysis

Pain and swelling of a limb following creation of arterio-venous fistula (AVF) are often attributable to vascular disorders like venous hypertension or limb ischaemia. Here we report the case of a 70-years old man who developed pain and swelling of upper limb distal to the AVF during second post-operative week due to a complex regional pain syndrome (CRPS). CRPS is characterized by pain that is disproportionate to the invoking injury, autonomic dysfunction, trophic changes and functional impairment of affected limb. Hyperalgesia and allodynia are pain patterns characteristic of CRPS. CRPS has been reported rarely following AVF creation surgery. Prompt diagnosis of CRPS is important to avoid misdiagnosis of vascular disorders and for implementation of right therapeutic strategy.

Local subcutaneous lidocaine injection for the treatment of complex regional pain syndrome: a case report and literature review

A 14-year-old child was diagnosed with complex regional pain syndrome (CRPS) after bromhidrosis surgery. She experienced a stinging, knife-like, and intermittent attack pain, accompanied by numbness of both upper limbs and limited movements. Ultrasound-guided radiofrequency surgery on the peripheral nerve did not reduce pain. Then, gabapentin 300 mg three times a day and 2% lidocaine by local subcutaneous injection once a day for 3 days were administrated. After the local subcutaneous injection of lidocaine, the pain was significantly relieved, and the pain induced by skin touch at the scar disappeared. No pain recurred after the 1-month follow-up. An evidence-based literature review showed that local or systemic intravenous lidocaine was used to reduce adult CRPS symptoms but less has been reported in children. In our case, a local subcutaneous injection of 2% lidocaine in a child for CRPS treatment was reported to be effective in relieving complex local pain with favorable outcomes. Though further high-quality randomized controlled trials are needed to investigate the effects and safety of local subcutaneous lidocaine injection on pain relief in children with CRPS, it could still provide a relatively safe and effective adjuvant therapy for minor patients.

Morphological and electrophysiological evaluation of median and ulnar nerve in complex regional pain syndrome type 1

OBJECTIVE

Complex regional pain syndrome (CRPS) can be distinguished as type I without and type II with electrophysiological evidence of major nerve lesion. The pathophysiology of both subgroups is still under investigation. The aim of this research is to demonstrate the nerve morphology and electrophysiology in CRPS type I patients.

MATERIALS AND METHODS

Bilateral median and ulnar nerve cross-sectional areas were evaluated with ultrasound and also median and ulnar nerve conduction studies of both hands were performed. Cross-sectional areas of median and ulnar nerves and nerve conduction studies in healthy controls were also obtained and compared with the patients.

RESULTS

Twenty-five male patients and 11 healthy male controls were enrolled in the study. The mean age of the patients was 24.08 ± 5.50 years and controls was 23.18 ± 5.09 (p > 0.05). Compound muscle action potential (CMAP) and sensory nerve action potential (SNAP) amplitudes of the diseased side were found significantly lower than the healthy side (p < 0.05). Both median and ulnar nerve distal motor latency values were significantly higher in the patient group (p < 0.05). There was no significant difference in the median and ulnar nerve cross-sectional area when compared with the opposite extremity and healthy volunteers.

CONCLUSION

The lower SNAP and CMAP amplitudes of the median and ulnar nerves compared to the healthy side and the prolongation of the affected side median and ulnar nerve distal motor latencies of the affected individuals may indicate axonal involvement in patients with CRPS type 1. Decreased CMAP amplitudes may also indicate muscle atrophy due to a decrease in the number of functional motor units.

Immunoregulatory Effect of Preventive Supplementation of Omega-3 Fatty Acid in a Complex Regional Pain Syndrome Type I Model in Mice

Objective

Complex regional pain syndrome (CRPS) is usually triggered by trauma or a surgical procedure, and it typically becomes an established one after an intense inflammatory process with chronic pain and edema as the main symptoms. Available treatments for CRPS have low efficacy. This study aimed to evaluate the clinical and immunoregulatory effects of omega-3 polyunsaturated fatty acid (PUFA) supplementation on paw edema and anti- and pro-inflammatory cytokines and macrophage phenotypes in the chronic post-ischemia pain (CPIP) preclinical model of CRPS-Type I.

Methods

Female Swiss mice were supplemented with omega-3, corn oil, or saline and then submitted to the CPIP model of ischemia/reperfusion (I/R) injury. Supplementation was carried out for 30 days prior to and up to 2 or 15 days after the induction of CPIP, according to experimental protocols. The supplementation protocol included 1,500 mg/kg of omega-3 or corn oil through an intragastric route (gavage). Paw edema, interleukin- (IL-) 4, IL-10, transforming growth factor-β1 (TGF-β1), monocyte chemotactic protein-1 (MCP-1), and tumor necrosis factor (TNF) were then measured in the paw skin and muscle by enzyme-linked immunosorbent assay (ELISA), and macrophage phenotypes (M1 and M2) assessed in the paw muscle by Western blotting.

Results

The CPIP model induced an increase in paw thickness up to 72 h post-I/R. Mice supplemented with omega-3 compared to the saline group displayed reduced edema but neither altered skin IL-4 or skin and muscle TGF-β1, TNF, and MCP-1 concentrations, nor did they exhibit significantly altered muscle macrophage phenotype on the 2nd-day post-CPIP. However, omega-3 supplementation reversed the I/R-related reduction in IL-4 in the paw muscle compared to groups supplemented with saline and corn oil. Furthermore, omega-3 promoted the reduction of IL-10 levels in the paw skin, compared to animals with lesions supplemented with saline, until the 2nd-day post-CPIP. On the 15th day post-CPIP, IL-10 was significantly increased in the muscle of animals supplemented with omega-3 compared to the saline group.

Conclusion

The results suggest that omega-3 PUFA supplementation has anti-inflammatory effects in the CPIP model of CRPS-Type I, significantly reducing paw edema and regulating concentrations of anti-inflammatory cytokines, including IL-4 and IL-10.

A randomised placebo-controlled clinical trial on the efficacy of local lidocaine injections and oral citalopram for the treatment of complex regional pain syndrome

BACKGROUND

Complex regional pain syndrome (CRPS) is a neuropathic pain condition with no universally recognised treatment. The study evaluates the efficacy of a therapeutic protocol consisting of oral citalopram and lidocaine injections in patients affected by CRPS.

METHODS

Between January 2010 and December 2014, 150 consecutive patients with CRPS were enrolled in the study and randomly assigned into three groups: group one - lidocaine injection and oral citalopram; group two - lidocaine injection and oral placebo; and group three - injective and oral placebo. The Impairment Sum Score (ISS) was used to assess the severity of CRPS before, as well as at regular intervals after treatment commenced. Statistical significance (p < 0.05) was determined by paired t-tests.

RESULTS

The combined treatment proved to be more effective (ISS 47.6 to 12.6) than local anaesthetic alone (ISS 47.5 to 21.5) and to placebo (ISS 47.2 to 29.9).

CONCLUSION

This study indicates that CRPS may be managed with well-tolerated association of oral citalopram and lidocaine injections.

Lightning-Storm Periungual Capillaries in a Patient with Complex Regional Pain Syndrome Type I

Introduction

Complex regional pain syndrome (CRPS) is characterized by chronic pain out of proportion to injury following trauma. CRPS most commonly results after crush-type injury to the hand and may be associated with various cutaneous symptoms believed to be driven by vasomotor instability. Existing reports in the literature have employed a range of methodologies to describe and evaluate cutaneous and vascular changes in CRPS, though there exists no current gold standard for diagnosis.

Case Presentation

Here, we report a 71-year-old male with a 10-year history of CRPS who presented with abnormal capillaries on onychoscopy, demonstrating a "lightning-storm" pattern.

Conclusion

Previous studies have shown increased blood flow to the cutis in the early stage of CRPS, yet diminished cutaneous flow during the later stages. However, one study showed increased nail capillary diameter in patients with later stage CRPS. Due to a variety of reported clinical characteristics and a nonspecific clinic presentation, both the recognition and diagnosis of CRPS is difficult. Nail fold capillaroscopy may be a useful and accessible tool for evaluating patients with CRPS.

Post-stroke complex regional pain syndrome and related factors: Experiences from a tertiary rehabilitation center

OBJECTIVE

In this study, it is aimed to determine the risk factors associated with CRPS after stroke and the clinical parameters of the patients and the treatment agents used for CPRS METHOD: 213 hemiplegic patients with CRPS diagnosed in Group 1 and 213 hemiplegic patients without CRPS in group 2 (control group) were included in the study designed retrospectively. Demographic data of the patients, Brunnstrom stage, Modified Ashworth scale, Barthel index were recorded from patients files. Associated risk faktors with CRPS such as Shoulder subluxation, adhesive capsulitis, fracture, deep vein thrombosis, spasticity, neglect, visual field defect, heterotopic ossification, entrapment neuropathies, brachial plexus damage, pressure wound, lower respiratory tract infection (LRTI), urinary tract infection, epilepsy, and depression were questioned. In addition, clinical findings, medical treatments, and physical therapy agents used were recorded.

RESULTS

The average age of the participants was 67.9 ± 10.3 in group 1 and 66.1 ± 9.9 in group 2. According to the multivariate logistic regression analysis, the presence of the duration of hemiplegi, the duration of hospitalization, shoulder subluxation, soft tissue lesion, adhesive capsulitis, spasticity, entrapment neuropathy, brachial plexus ınjury, protein energy malnutrition, LRTI, urinary infection, depression, coronary artery disease were significantly increased the development of CRPS (p<0.05). As a clinical parameter, edema was present in 95.3% of the patients, while trophic change was the lowest in 1.9%. While sensory reeducation was used in all patients in physical therapy, ganglion blockade was the lowest with 0.9% of patients. In medical treatment, the use of oral paracetamol was 28.2%, while the use of gabapentin was the last with 8.9%.

CONCLUSIONS

In our study, the risk factors of CRPS after hemiplegia, which are as important as its treatment, as well as its diagnosis and prevention, are shown.

Type 1 Complex Regional Pain Syndrome After Subacromial Shoulder Surgery: Incidence and Risk Factor Analysis

INTRODUCTION

Complex Regional Pain Syndrome type 1 (CRPS1) is a potential complication, affecting the prognosis of functional joint recovery. Its incidence ranges from 2 to 40% depending on the series and the joints involved. Very few studies have evaluated the incidence of CRPS after shoulder surgery. The objective of our study was to determine the incidence of CRPS1 and to identify any pre-operative risk factors associated with its emergence after extra-articular subacromial space surgery.

MATERIAL AND METHODS

This is a retrospective single-centre study of patients who underwent surgery for a subacromial extra-articular shoulder pathology from January 2016 to December 2016 and included a follow-up period of at least 6 months. The primary inclusion criterion was developing a CRPS1 as defined by Veldman. A pre- and post-operative clinical assessment was performed based on the Constant (Cst) score.

RESULTS

Among the 287 patients, with an average follow-up period of 6.5 months, included in the study, 38 (13%) presented with post-operative CRPS1. Treated hypothyroidism (OR = 3.79; 95% CI 1.58;9.07; p = 0.003), open surgery (OR = 2.92; 95% CI 1.35-6.32; p = 0.007) and the level of daily physical activity from the Cst score (OR = 0.088; 95% CI 0.79;0.97; p = 0.015) were found to be significantly associated with the onset of CRPS1.

CONCLUSION

CRPS1 affected more than 10% of patients who underwent surgery for a subacromial shoulder pathology. The current study identified hypothyroidism, open surgery, and pre-operative clinical status as risk factors for the onset of this complication. These parameters should, therefore, be taken into consideration during the patient's pre-operative consultation.

Spinal cord stimulation for the treatment of complex regional pain syndrome leads to improvement of quality of life, reduction of pain and psychological distress: a retrospective case series with 24 months follow up

Background and aims

Complex regional pain syndrome (CRPS) is a common pain condition which is characterized by pain, functional impairment, and trophic changes. Neurosurgical treatment is not widely offered. In this study the treatment with spinal cord stimulation (SCS) was evaluated over 24 months follow up.

Methods

A retrospective case analysis of six patients with severe CRPS was performed. Pain chronicity was recorded with the Mainz Pain Staging System (MPSS). Pain intensity (NRS), activity level and health-related quality of life (EQ-5D-5L), the actual mood state (ASTS), and treatment satisfaction (CSQ-8) were assessed. All patients received conventional pharmacological treatments including multimodal pain therapy through their local pain therapist or in specialized centers as well as physical therapy. A SCS electrode was implanted for trial stimulation. After successful trial a neurostimulator was implanted and connected to the electrode. Patients were retrospectively analyzed before implantation and 6, 12 and 24 months postoperatively. Statistical analysis was performed using Mann–Whitney U and Wilcoxon rank-sum test.

Results

Patients median age was 43 years (IQR25−75 37–43 years). The median MPSS Score was 3 of 3 indicating a high pain chronicity. Median NRS before implantation of the neurostimulator was 8.8 (IQR25−75 7.6–9.3). A reduction to 7.8 (IQR25−75 4.8–8.1; p = 0.14) after 6 months, 6.5 (IQR25−75 3.8–8.1; p = 0.08) after 1 year, and 6.8 (IQR25−75 3.8–8.5; p = 0.15) after 2 years was achieved. Median EQ-5D-5L index value before treatment was 0.27 (IQR25−75 0.25–0.41) indicating a severely lowered quality of life. A significant improvement to 0.53 (IQR25−75 0.26–0.65; p = 0.03) after 6 months, 0.58 (IQR25−75 0.26–0.84; p = 0.03) after 1 year as well as after 2 years was seen. ASTS scale showed an increase of values for positive mood, and a reduction in values for sorrow, fatigue, anger and desperation during the whole follow up period. The treatment satisfaction in the whole cohort with a median CSQ-8 value of 29.5 of 32 was very high.

Conclusion

The results of this small case series showed a significant improvement of the EQ-5D-5L after implantation of a neurostimulator. NRS reduction was not significant but a clear tendency towards reduced values was observed. We therefore conclude that SCS is an alternative option to relieve chronic pain and psychological distress originating from CRPS if non-invasive managements of severe CRPS failed. The preoperative selection plays a crucial role for good results.

Implications

CRPS is difficult to treat. SCS is an alternative option to improve the quality of life and relieve chronic pain originating from severe CRPS if conservative treatment modalities fail. Further psychological distress is reduced in long-term follow up. SCS should be kept in mind for therapy refractory cases.

Influence of vitamin C on the incidence of CRPS-I after subacromial shoulder surgery

PURPOSE

The primary aim of this study was to determine whether postoperative administration of vitamin C (VC) is associated with reduced risk of complex regional pain syndrome type I (CRPS-I) after subacromial shoulder surgery (SaSS). The secondary objective of the study was to identify risk factor for the development of CRPS-I after SaSS.

MATERIALS AND METHODS

A retrospective cohort study was performed to evaluate 542 patients undergoing SaSS from January 2015 to December 2016. The cohort was divided into two groups based on VC administration [Group I (no VC) and Group II (500 mg/day oral VC for 50 days postoperatively)]. The relationship between VC administration and development of CRPS-I was assessed. Demographics, preoperative clinical parameters, and operative variables were evaluated to determine their effect on the incidence of CRPS-I.

RESULTS

A total of 267 patients (Group II) undergoing SaSS received VC, and 266 patients (Group I) did not. The incidence of CRPS-I was significantly different between two groups (36(13%) vs 18(7%), p = 0.009). Multivariable regression, however, demonstrated that VC reduced the risk of CRPS-I after SaSS by > 50% (aOR = 0.49; 95% CI 0.27-0.91). Patients undergoing open surgery (aOR = 2.19; 95% CI 1.2-4.0) were more likely to develop CRPS-I postoperatively. Higher preoperative Constant score (aOR = 0.94; 95% CI 0.91-0.98) was associated with lower risk for CRPS-I development.

CONCLUSIONS

The present study found that VC administered prophylactically for 50 days postoperatively is effective in preventing CRPS-I development after SaSS. CRPS-I is a common complication following SaSS, especially in the setting of an open approach. The authors recommend preventive management with VC and arthroscopic approaches when possible for SaSS.

LEVEL OF EVIDENCE III

Retrospective comparative study.

The Legal Doctrine on the Liability of Physicians in Medical Malpractice Lawsuits Involving Complex Regional Pain Syndrome

BACKGROUND

Complex regional pain syndrome (CRPS) involves severe pain and it is difficult to identify the exact cause or pathogenesis. Therefore, there are controversies regarding legal issues related to the establishment of damage in medical malpractice lawsuits involving CRPS. This study aimed to analyze malpractice lawsuits involving CRPS, which occurred after the disputed medical treatment, to provide information on the courts' opinion and characteristics of the cases.

METHODS

This study analyzed 23 lawsuit judgments involving CRPS that were sentenced from 2005 to 2015.

RESULTS

A total of 12 of the 23 cases were partially ruled in favor of the plaintiff. The average amount (KRW) claimed was 470,638,385 ± 860,634,092 (21,000,000 to 4,020,000,000), and that awarded was 72,906,843 ± 53,389,367 (15,000,000 to 181,080,803). Sixteen of the 23 cases had CRPS type I. In 11 of 23 cases, the site of the pain was located in the lower limb and in 14 cases there was no presence of trauma or event prior to medical treatment.

CONCLUSION

Nerve injury was the most frequent reason for taking responsibility in compensating damage in malpractice cases involving CRPS. Physicians should consider various possibilities of such complications in medical practices. It is important to identify and improve areas which need to be improved for patient safety through analyzing the lawsuit judgment cases.

Risk Factors for Post-treatment Complex Regional Pain Syndrome (CRPS): An Analysis of 647 Cases of CRPS from the Danish Patient Compensation Association

OBJECTIVES

Complex regional pain syndrome is a challenging condition that includes a broad spectrum of sensory, autonomic, and motor features predominantly in extremities recovering from a trauma. Few large-scale studies have addressed occurrence of and factors associated with complex regional pain syndrome (CRPS) following orthopedic treatment. The present study aimed to identify factors associated with post-treatment development of CRPS.

METHODS

Using the Danish Patient Compensation Association's database, we identified 647 patients claiming post-treatment CRPS between 1992 and 2015. Age, gender, initial diagnosis, treatment, and amount of compensation were extracted. Multivariate logistic regressions were performed to identify variables associated with approval of the claim. For carpal tunnel syndrome (CTS) patients, we registered whether symptoms were bilateral or unilateral and if neurophysiology prior to treatment was pathologic.

RESULTS

The following ratios were found: women:men was 4:1, primary diagnosis to the upper limb:lower limb was 2.5:1, and surgical:nonsurgical treatment was 3:1. Mean age was 47.5 ± 13.7 years, and no intergender difference was detected. Antebrachial fracture (23%) and CTS (9%) were the most common primary conditions. Surgical treatment was associated with approval of the claim (odds ratio 3.5, 95% confidence interval 2.3 to 5.3; P < 0.001). Half of CTS patients had normal neurophysiology prior to surgery; among patients with unilateral symptoms, 71.4% had normal neurophysiology.

CONCLUSIONS

Female gender, surgical treatment, and treatment to the upper limb were risk factors. Elective surgery accounted for a large number of post-treatment CRPS patients. In CTS patients developing CRPS, normal neurophysiological examination findings were common, and it could be suspected that these patients were suffering from an pre-clinical stage of CRPS, not CTS.

[Complex pain regional syndrome after distal radius fractures]

Complex regional pain syndrome (CPRS) greatly affects the outcomes of distal radius fractures in terms of functional recovery, time away from work and patient satisfaction. The diagnosis is sometimes difficult to make in the immediate post-injury period. The disproportionate nature of the pain in the absence of differential diagnoses and the presence of a pain-free interval should arouse suspicion. The natural history consists of spontaneous improvement except in some refractory forms. The treatment is multidisciplinary combining a physician specializing in pain, therapist and psychologist coordinated by the surgeon who must not abandon the patient. Treatment aims to improve the patient's comfort and quality of life. Recent treatment approaches aimed at improving cortical reorganization have demonstrated their effectiveness. Surgery has to be considered even in the acute phase to address any causes of pain that can be resolved and address secondary stiffness. Significant progress has to be made in our understanding of the pathogenesis of CPRS to improve treatment and shift this condition to a regional pain syndrome.

The effectiveness of transcutaneous electrical nerve stimulation in the management of patients with complex regional pain syndrome: A randomized, double-blinded, placebo-controlled prospective study

OBJECTIVE

To investigate the effect of transcutaneous electrical nerve stimulation (TENS) on clinical recovery in the management of patients with complex regional pain syndrome Type I (CRPS Type I).

MATERIAL AND METHOD

The study included 30 patients with stage 1 and 2 CRPS Type I in the upper extremities. The patients were randomly assigned into 2 groups, group 1 (n= 15) received conventional TENS therapy for 20 minutes, and group 2 (n= 15) received sham TENS therapy. The standard physical therapy program, which included contrast bath for 20 minutes; whirlpool bath for 15 minutes; assisted active and passive range of motion, and static stretching exercises up to the pain threshold, was also conducted in both groups. Therapy was scheduled for 15 sessions. A visual analogue scale (VAS) was used to assess spontaneous pain. The Leeds Assessment of Neuropathic Signs and Symptoms (LANSS) scale and the Douleur Neuropathique en 4 Questions (DN-4) were used to assess neuropathic pain. In addition, range of motion (ROM) was measured using a goniometer and volumetric measurements were taken to assess edema. Functional capacity was assessed using a hand dynamometer and the Duruöz Hand Index (DHI). All measurements were performed at baseline and after therapy.

RESULTS

Significant improvements were achieved in spontaneous and neuropathic pain scores, edema, ROM, and functional capacity in both groups (p< 0.05). However, improvement was found to be significantly greater in group 1 regarding pain intensity, neuropathic pain assessed using LANNS, edema, and in the 2nd-3rd finger ROM measurements (p< 0.05). No significant difference was detected between groups regarding improvements in 4th-5th finger and wrist ROM measurements, grip strength, and DN4 and DHI scores (p> 0.05).

CONCLUSION

The addition of TENS to the physical therapy program was seen to make a significant contribution to clinical recovery in CRPS Type 1.

A rare complication of total knee arthroplasty: Type l complex regional pain syndrome of the foot and ankle

Complex regional pain syndrome (CRPS) is a painful and disabling disorder that usually affects the extremities. This complication may affect the knee joint after total knee arthroplasty (TKA). We report a unique case of CRPS of the foot and ankle, which was an unusual involvement site for CRPS after TKA.

Platelet and Erythrocyte Indexes in Complex Regional Pain Syndrome Type I

Objectives

This study aims to compare the levels of platelet and erythrocyte indexes including mean platelet volume, platelet distribution width (PDW), and red blood cell distribution (RDW) values between complex regional pain syndrome (CRPS) type I patients and healthy controls to establish a marker of neuroinflammation that might be a potential factor involved in CRPS etiopathogenesis.

Patients and methods

A total of 21 patients (14 males, 7 females; mean age 35.0±15.4 years; range 15 to 69 years) with a diagnosis of CRPS type I and 44 age- and sex-similar healthy controls (29 males, 15 females; mean age 35.8±8.5 years; range 16 to 53 years) were included in this study. Mean platelet volume, PDW, RDW, white blood count, hemoglobin, erythrocyte sedimentation rate, and C-reactive protein levels, and neutrophil to lymphocyte ratio and thrombocyte to lymphocyte ratio were compared between the patient and control groups.

Results

No differences were noted between patient and control groups in terms of erythrocyte sedimentation rate and C-reactive protein levels, white blood cell, neutrophil, lymphocyte and thrombocyte counts, and neutrophil to lymphocyte and thrombocyte to lymphocyte ratios (all p>0.05). When compared with controls, patients had significantly higher mean corpuscular volume (p=0.019) and RDW (p=0.002) values, and a lower PDW level (p=0.006).

Conclusion

Differences in PDW, RDW, and mean corpuscular volume values between patients and controls might support the potential role of neuroinflammation in the etiopathogenesis of CRPS type I. Prospective studies with larger sample sizes are warranted in the early detection and differential diagnosis of CRPS type I.

Treatment of complex regional pain syndrome type I with bisphosphonates

Complex regional pain syndrome type I (CRPS-I) is a common and disabling disorder affecting a peripheral limb, usually developing after a trauma to an extremity. CRPS-I is characterised by presence of spontaneous pain, allodynia and hyperalgesia, disproportionate to the inciting event and by a variety of autonomic disturbances and trophic abnormalities. The pathophysiology of CRPS-I has not been fully understood. Experimental models have suggested that an initial triggering event may produce the release of proinflammatory neuropeptides and cytokines, generating a sort of neurogenic inflammation. Thereafter, increased microvascular permeability and intramedullary pressure, reduced oxygen extraction and cellular hypoxia maintain and make the disease worse, producing metabolic tissue acidosis. In this context, it is probable that, far from being a key player, the sympathetic nervous system contributes interacting with these mechanisms and producing vasomotor disturbances. Bisphosphonates (BPs) are potent inhibitors of osteoclastic activity widely used for the management of osteoporosis and other metabolic bone diseases. Their primary pharmacological action is the reduction of bone turnover. An enhanced osteoclastic activity has never been clearly demonstrated in CRPS-I. Therefore, it is likely that the positive effects of BPs in this condition are not related to their antiresorptive properties, but to a more complex interaction between these pharmacological agents and the pathophysiological mechanisms underlying CRPS-I. Results of several clinical trials have suggested the potential beneficial effects of BPs in CRPS-I. In five randomised controlled trials, oral and intravenous alendronate and intravenous clodronate, pamidronate and neridronate demonstrated to be effective in reducing pain and improving physical function in patients presenting with CRPS-I, with a good profile of safety and tolerability. Although these trials have a number of limitations, including the small samples enrolled, there is sufficient evidence to support the use of BPs as agents of choice in the management of CRPS-I.

Management of complications relating to complex traumatic hand injuries

Complex hand injuries result in local trauma to osseous, neurovascular, and soft tissue structures. The large amount of energy imparted to these tissues may result in complex regional pain syndrome, stiffness, or infection. Unfortunately, a good outcome may not only depend on the technical aspects of the procedure but on the expectations, occupation, age, and other factors that are out of the surgeon's control. The best treatment for these complications is prevention; however, this review offers strategies to combat the complications once they arise.

The effectiveness of bivalving, cast spreading, and webril cutting to reduce cast pressure in a fiberglass short arm cast

BACKGROUND

A fiberglass short arm cast can be used to treat a distal radial fracture, but posttraumatic edema may lead to excessive cast tightness and resultant soft-tissue injury. We sought to quantify a simulated edema-induced pressure within a fiberglass short arm cast and to determine the effectiveness of different cast-cutting methods for pressure reduction. We hypothesized that cast cutting could eliminate all clinically relevant pressure and Ace wrap would insignificantly increase pressure.

METHODS

Skin surface pressure under fiberglass short arm casts was measured on ninety wrists from forty-five volunteers randomly assigned to one cast-cutting method: single-cut (cast bivalve and Ace wrap), double-cut (cast bivalve, spread, and Ace wrap), or triple-cut (cast bivalve, spread, Webril cut, and Ace wrap). Each wrist was immobilized in a cast in the neutral position with one roll of 2-inch (5.1-cm) cotton Webril and one roll of 2-inch (5.1-cm) fiberglass. Each fiberglass short arm cast contained an empty intravenous fluid bag in which we infused air. This simulated edema, which generated a skin surface pressure, which was measured by a pressure transducer.

RESULTS

Each cast-cutting method significantly reduced (p < 0.0001) the skin surface pressure from the average maximum of 92.5 mm Hg in a non-fracture setting. Prior to Ace wrapping, there was a reduction in skin surface pressure of 70.8% for the single-cut method, 85.1% for the double-cut method, and 99.9% for the triple-cut method. Ace wrap significantly increased skin surface pressure (p < 0.0001), lessening the effectiveness of cast cutting. There was an overall reduction in skin surface pressure of 55.9% for the single-cut method, 64.3% for the double-cut method, and 77.2% for the triple-cut method. Throughout our study, women had significantly higher skin surface pressure than men (p < 0.0001); the average maximum was 104.4 mm Hg for women and 81.1 mm Hg for men.

CONCLUSIONS

The single-cut method provides the greatest pressure reduction, but only the triple-cut method eliminated all relevant skin surface pressure. Ace wrapping a cut cast noticeably increased skin surface pressure.

CLINICAL RELEVANCE

In volunteers without a fracture, only the triple-cut method is effective enough to eliminate clinically relevant skin surface pressure. Ace wrap should be applied with caution after the cast is cut. The specific effect on pressure reduction in a patient who requires some soft-tissue pressure to maintain fracture reduction was not studied.