Efficacy and safety of high-dose vitamin C on complex regional pain syndrome in extremity trauma and surgery--systematic review and meta-analysis

Unveiling the potential impact of vitamin C in postoperative spinal pain

BACKGROUND

Spinal surgery is a common procedure associated with significant postoperative pain, and identifying effective interventions to manage this pain is crucial for optimizing patient outcomes. This review assesses the existing literature to determine the overall impact of vitamin C supplementation on spinal postoperative pain. Vitamin C, also known as ascorbic acid, is an essential nutrient that plays a vital role in numerous physiological processes. It functions as a potent antioxidant, neutralizing free radicals and reducing oxidative stress within the body. Furthermore, vitamin C is a cofactor in collagen synthesis, a crucial component of connective tissues, including those found in the spinal structures. Given its antioxidant and collagen-promoting properties, vitamin C has piqued interest as a potential therapeutic option for postoperative spinal pain. Based on the available evidence, vitamin C may have a beneficial effect on postoperative spinal pain, including reducing pain scores, analgesic consumption, and the incidence of complications such as complex regional pain syndrome. However, more research is needed to fully understand the optimal dosage and duration of vitamin C supplementation for postoperative pain management.

CONCLUSION

Vitamin C could be considered a potentially beneficial adjunctive therapy for managing spinal postoperative pain, but its routine use requires further investigation.

The role of diet and non-pharmacologic supplements in the treatment of chronic neuropathic pain: A systematic review

BACKGROUND/IMPORTANCE

Dietary interventions, vitamins, and nutritional supplementation are playing an increasingly important role in the management of neuropathic pain. Current pharmacological treatments are poorly tolerated and ineffective in many cases.

OBJECTIVE

This systematic review aims to study the efficacy of dietary interventions, vitamins, and nutritional supplementation in the management of chronic neuropathic pain in adults.

EVIDENCE REVIEW

The review followed PRISMA guidelines and was registered with PROSPERO (#CRD42022300312). Ten databases and gray literature, including Embase.com, MEDLINE and Web of Science, were systematically searched using a combination of keywords and controlled vocabulary related to chronic neuropathic pain and oral non-pharmacological supplements. Studies on adult humans published between 2000 and 2021 were considered for inclusion. The Cochrane Handbook was used to assess risk of bias, and Grading of Recommendations Assessment, Development, and Evaluation was used to determine overall quality of evidence.

FINDINGS

Forty studies were included in the final review, and results were categorized according to pain type including pain related to chemotherapy-induced peripheral neuropathy (CIPN, 22 studies, including 3 prospective cohorts), diabetic peripheral neuropathy (DPN, 13 studies, including 2 prospective), complex regional pain syndrome (CRPS-I, 3 studies, including 1 prospective), and other (2 studies, both RCT). The CIPN studies used various interventions including goshajinkigan (4 studies), vitamin E (5), vitamin B12 (3), glutamine (3), N-acetyl-cysteine (2), acetyl-l-carnitine (2), guilongtonluofang (1), ninjin'yoeito (1), alpha-lipoic acid (1), l-carnosine (1), magnesium and calcium (1), crocin (1), and antioxidants (1), with some studies involving multiple interventions. All CIPN studies involved varying cancers and/or chemotherapies, advising caution for generalizability of results. Interventions for DPN included alpha-lipoic acid (5 studies), vitamin B12 (3), acetyl-l-carnitine (3), vitamin E (1), vitamin D (2), and a low-fat plant-based diet (1). Vitamin C was studied to treat CRPS-I (3 studies, including 1 prospective). Magnesium (1) and St. John's wort (1) were studied for other or mixed neuropathologies.

CONCLUSIONS

Based on the review, we cannot recommend any supplement use for the management of CIPN, although further research into N-acetyl-cysteine, l-carnosine, crocin, and magnesium is warranted. Acetyl-l-carnitine was found to be likely ineffective or harmful. Alpha-lipoic acid was not found effective. Studies with goshajinkigan, vitamin B12, vitamin E, and glutamine had conflicting results regarding efficacy, with one goshajinkigan study finding it harmful. Guilongtonluofang, ninjin'yoeito, and antioxidants showed various degrees of potential effectiveness. Regarding DPN, our review supports the use of alpha-lipoic acid, acetyl-l-carnitine, and vitamin D. The early use of vitamin C prophylaxis for the development of CRPS-I also seems promising. Further research is warranted to confirm these findings.

Impact of vitamin C on the reduction of opioid consumption after an emergency department visit for acute musculoskeletal pain: a double-blind randomised control trial protocol

INTRODUCTION

Recent evidence has shown that vitamin C has some analgesic properties in addition to its antioxidant effect and can, therefore, reduce opioid use during recovery time. Vitamin C analgesic effect has been explored mostly during short-term postoperative context or in disease-specific chronic pain prevention, but never after acute musculoskeletal injuries, which are often seen in the emergency department (ED). The protocol's primary aim is to compare the total morphine 5 mg pills consumed during a 2-week follow-up between patients receiving vitamin C or a placebo after ED discharge for an acute musculoskeletal pain complaint.

METHODS AND ANALYSIS

We will conduct a two-centre double-blind randomised placebo-controlled trial with 464 participants distributed in two arms, one group receiving 1000 mg of vitamin C two times a day for 14 days and another one receiving a placebo. Participants will be ≥18 years of age, treated in ED for acute musculoskeletal pain present for less than 2 weeks and discharged with an opioid prescription for home pain management. Total morphine 5 mg pills consumed during the 2-week follow-up will be assessed via an electronic (or paper) diary. In addition, patients will report their daily pain intensity, pain relief, side effects and other types of pain medication or other non-pharmacological approach used. Three months after the injury, participants will also be contacted to evaluate chronic pain development. We hypothesised that vitamin C, compared with a placebo, will reduce opioid consumption during a 14-day follow-up for ED discharged patients treated for acute musculoskeletal pain.

ETHICS AND DISSEMINATION

This study has received approval from the Ethics Review Committee from the 'Comité d'éthique de la recherche du CIUSSS du Nord-de-l'Île-de-Montréal (No 2023-2442)'. Findings will be disseminated through scientific conferences and peer-reviewed journal publication. The data sets generated during the study will be available from the corresponding author on reasonable request.

TRIAL REGISTRATION NUMBER

NCT05555576 ClinicalTrials.Gov PRS.

Separating Fact From Fiction: A Nationwide Longitudinal Examination of Complex Regional Pain Syndrome Following Treatment of Dupuytren Contracture

BACKGROUND

One of the most feared complications following treatment of Dupuytren contracture is complex regional pain syndrome (CRPS). This study aims to provide a national perspective on the incidence of CRPS following treatment of Dupuytren contracture and identify patient factors to target for risk reduction.

METHODS

Using the Truven MarketScan databases from 2007 to 2016, individuals aged ≥18 years who developed CRPS within 1 year of treatment of Dupuytren contracture were identified using the International Classification of Disease diagnosis code for CRPS. Predictor variables included: age, sex, employment status, region, type of procedure, and concurrent carpal tunnel surgery. Multivariable logistic regression was used to analyze outcomes.

RESULTS

In all, 48 327 patients received treatment for Dupuytren contracture, including collagenase injection (13.6%); percutaneous palmar fasciotomy (10.3%); open palmar fasciotomy (3.9%); palmar fasciectomy with 0 (10.8%), 1 (29.2%), or multiple (19.6%) digit releases; or a combination of these procedures (12.8%). One hundred forty-five patients (0.31%) were diagnosed with CRPS at a mean of 3.4 months (standard deviation, 2.3) following treatment. Significant predictors of CRPS included female sex (odds ratio [OR], 2.02; P < .001), Southern region (OR, 1.80; P = .022), long-term disability status (OR, 4.73; P = .035), palmar fasciectomy with release of 1 (OR, 5.91; P = .003) or >1 digit (OR, 13.32; P < .001), or multiple concurrent procedures for Dupuytren contracture (OR, 8.23; P = .001).

CONCLUSIONS

Based on national commercial claims data, there is a lower incidence of CRPS following treatment of Dupuytren contracture than previously reported. Risk factors identified should help with preoperative counseling and assist clinicians in targeting risk reduction measures.

Effect of Perioperative Vitamin C on the Incidence of Complex Regional Pain Syndrome: A Systematic Review and Meta-Analysis

Complex regional pain syndrome type 1 (CRPS-I) is a complex complication that occurs after limb extremity surgeries. Controversy exists regarding the effectiveness of vitamin C in reducing that condition. Therefore, we conducted this systematic review and meta-analysis to assess the role of vitamin C on CRPS-I and functional outcomes after distal radius, wrist, foot, and ankle surgeries. We searched Medline (via PubMed), Embase, the Cochrane Library, Clinicaltrial.gov, and Google Scholar for relevant studies comparing perioperative vitamin C versus placebo after distal radius, wrist, foot, and ankle surgeries from infinity to May 2021. Continuous data such as functional outcomes and pain scores were pooled as mean differences, while dichotomous variables such as the incidence of complex regional pain syndrome and complications were pooled as odds ratios, with 95% confidence interval, using R software (meta package, version 4.9-0) for Windows. Eight studies were included. The timeframe for vitamin C administration in each study ranged from 42 to 50 days postinjury and/or surgical fixation. The effect size showed that vitamin C was associated with a decreased rate of CRPS-1 than placebo (odds ratio 0.33, 95% confidence interval [0.17, 0.63]). No significant difference was found between vitamin C and placebo in terms of complications (odds ratio 1.90, 95% confidence interval [0.99, 3.65]), functional outcomes (mean difference 6.37, 95% confidence interval [-1.40, 14.15]), and pain scores (mean difference -0.14, 95% confidence interval [-1.07, 0.79]). Overall, vitamin C was associated with a decreased rate of CRPS-I than placebo, while no significant difference was found regarding complications, functional outcomes, and pain scores. These results hold true when stratifying fracture type (distal radius, ankle, and foot surgeries) and vitamin C dose (500 mg or 1 g).

Complex Regional Pain Syndrome: Practical Diagnostic and Treatment Guidelines, 5th Edition

There have been some modest recent advancements in the research of Complex Regional Pain Syndrome, yet the amount and quality of the work in this complicated multifactorial disease remains low (with some notable exceptions; e.g., the recent work on the dorsal root ganglion stimulation). The semi-systematic (though in some cases narrative) approach to review is necessary so that we might treat our patients while waiting for "better research." This semi-systematic review was conducted by experts in the field, (deliberately) some of whom are promising young researchers supplemented by the experience of "elder statesman" researchers, who all mention the system they have used to examine the literature. What we found is generally low- to medium-quality research with small numbers of subjects; however, there are some recent exceptions to this. The primary reason for this paucity of research is the fact that this is a rare disease, and it is very difficult to acquire a sufficient sample size for statistical significance using traditional statistical approaches. Several larger trials have failed, probably due to using the broad general diagnostic criteria (the "Budapest" criteria) in a multifactorial/multi-mechanism disease. Responsive subsets can often be identified in these larger trials, but not sufficient to achieve statistically significant results in the general diagnostic grouping. This being the case the authors have necessarily included data from less compelling protocols, including trials such as case series and even in some instances case reports/empirical information. In the humanitarian spirit of treating our often desperate patients with this rare syndrome, without great evidence, we must take what data we can find (as in this work) and tailor a treatment regime for each patient.

From a Symptom-Based to a Mechanism-Based Pharmacotherapeutic Treatment in Complex Regional Pain Syndrome

Complex regional pain syndrome (CRPS) is a debilitating painful condition of a distal extremity that can develop after tissue damage. CRPS is thought to be a multimechanism syndrome and ideally the most prominent mechanism(s) should be targeted by drugs in an individually tailored manner. This review gives an overview of the action and evidence of current and future pharmacotherapeutic options for CRPS. The available options are grouped in four categories by their therapeutic actions on the CRPS mechanisms, i.e. inflammation, central sensitisation, vasomotor disturbances and motor disturbances. More knowledge about the underlying mechanisms of CRPS helps to specifically target important CRPS mechanisms. In the future, objective biomarkers could potentially aid in selecting appropriate mechanism-based drugs in order to increase the effectiveness of CRPS treatment. Using this approach, current and future pharmacotherapeutic options for CRPS should be studied in multicentre trials to prove their efficacy. The ultimate goal is to shift the symptom-based selection of therapy into a mechanism-based selection of therapy in CRPS.

Multivitamin Use in Enhanced Recovery After Surgery Protocols: A Cost Analysis

INTRODUCTION

Enhanced Recovery After Surgery (ERAS) protocols have shown significant benefits in multiple areas including early mobilization, improved pain control, and early oral intake. Deficient nutritional states may compromise the operative outcomes. Several essential vitamins, e.g., B12, C, D, and E, have demonstrated anti-inflammatory properties and may promote wound healing. Given the low risk of oral multivitamin supplementation and the potential benefits, we hypothesized that adding a multivitamin to our institution's ERAS protocols would be a low-cost perioperative intervention accounting for a very small fraction of the annual pharmacy budget.

METHODS

A cost analysis for vitamin supplementation for all adult orthopedic surgical cases for the fiscal year 2018 was conducted. To assess the potential cost for multivitamin supplementation in the perioperative period, the fiscal year 2018 pharmacy budget and current costs of multivitamins were obtained from the hospital pharmacy. Medication costs were obtained from the medical logistics ordering system at per unit (i.e., bottle) and per tablet levels for all formulary oral multivitamins. We also determined the number of adult orthopedic surgical cases for our facility in the fiscal year 2018 from our surgery scheduling system. The cost for supplementation for a single day (day of surgery), 1 week (first postoperative week), 6 weeks plus 1 week preop, and 6 months plus 1 week preop for all cases was then calculated.

RESULTS

Our institution's pharmacy budget for the fiscal year 2018 was $123 million dollars with two oral multivitamins on formulary. Prenatal tablets, containing vitamins A-E, calcium, iron, and zinc, cost $1.52 per bottle of 100 tablets and $0.0152 per tablet, while renal formulation tablets, containing water-soluble vitamins B and C, cost $2.79 per bottle of 100 tablets and $0.0279 per tablet. For one fiscal year, the medication cost to supplement every adult orthopedic surgery patient with an oral multivitamin for 1 day, 1 week, 6 weeks plus 1 week preop, and 6 months plus 1 week preop would range from $60.47 to $110.99, from $423.29 to $776.93, from $2,963.03 to $5,438.51, and from $10,582.25 to $19,423.25, respectively, depending on which multivitamin was prescribed. These costs would represent between 0.00005% and 0.00009% of the annual pharmacy budget for 1 day, between 0.0003% and 0.0006% for 1 week, between 0.00245% and 0.441% for 6 weeks plus 1 week preop, and between 0.00875% and 1.575% for 6 months plus 1 week preop, respectively.

DISCUSSION/CONCLUSIONS

The relative nutrient-deficient state in the perioperative patient from decreased oral intake contributes to the metabolic derangements resulting from the surgery. The current ERAS protocols help to mitigate this with early feeding, and the addition of multivitamin supplementation may enhance this process. Multivitamins are safe, widely accessible, and inexpensive, and early investigations of pain control and healing have shown encouraging results. Further prospective studies are needed for incorporating multivitamins into ERAS protocols in order to elucidate the effective dosages, duration of treatment, and effect on outcomes.

Non-drug pain relievers active on non-opioid pain mechanisms

This review is aimed to summarize the pain-relieving effect of non-drug substances, mostly prescribed as integrators in treatment of pain, including especially in chronic postoperative pain (CPSP) and in chronic back pain after acute episodes. Their use reflects the fact that the current treatments for these syndromes continue to pose problems of unsatisfactory responses in a significant portion of patients and/or of an excess of side effects like those noted in the present opioid crisis. As integrators are frequently introduced into the market without adequate clinical testing, this review is aimed to collect the present scientific evidence either preclinical or clinical for their effectiveness. In particular, we reviewed the data on the use of: B vitamins; vitamin C; vitamin D; alpha lipoic acid (ALA); N-acetylcysteine; acetyl L-carnitine; curcumin; boswellia serrata; magnesium; coenzyme Q10, and palmitoylethanolamide. The combination of preclinical findings and clinical observations strongly indicate that these compounds deserve more careful attention, some of them having interesting clinical potentials also in preventing chronic pain after an acute episode. In particular, examining their putative mechanisms of action it emerges that combinations of few of them may exert an extraordinary spectrum of activities on a large variety of pain-associated pathways and may be eventually used in combination with more traditional pain killers in order to extend the duration of the effect and to lower the doses. Convincing examples of effective combinations against pain are vitamin B complex plus gabapentin for CPSP, including neuropathic pain; vitamin B complex plus diclofenac against low back pain and also in association with gabapentin, and ALA for burning mouth syndrome. These as well as other examples need, however, careful controlled independent clinical studies confirming their role in therapy.

Vitamin C Could Prevent Complex Regional Pain Syndrome Type I in Trauma and Orthopedic Care? A Systematic Review of the Literature and Current Findings

The aim of this systematic review is to evaluate the efficacy of Vitamin C (VC) in preventing Complex Regional Pain Syndrome type I (CRPS-I) in fractures or surgery of the upper and lower extremities. During December 2020, Scopus and PubMed search was performed to analyze VC supplementation in preventing CRPS-I after trauma and orthopedic care, according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses guideline. Patient, Intervention, Comparison, Outcomes, Study Design model, and a modified version of the Coleman Methodology Score were used to analyze the included studies. The research was limited from 1990 to December 2020. Initial screening results identified 649 studies. After reviewing each study, six clinical studies were included in the study. A total of 2026 patients of whom 632 male and 1394 female were collected in our systematic review. During the entire follow-up period, the occurrence of CRPS-I was evaluated in 1939 patients. Five of the six analyzed studies were favoring prophylactic use of the 500-1000 mg daily dose of VC for 45-50 days after orthopedic or trauma care for prevention of CRPS-I. Only one study found no benefit in VC supplementation compared with placebo to prevent CRPS-I. Analysis of the literature suggests that a daily 500-1000 mg VC supplementation may reduce the onset of CRPS-I in trauma of upper/lower extremities and in orthopedic surgery.

A meta-analysis of randomized clinical trials on the impact of oral vitamin C supplementation on first-year outcomes in orthopedic patients

This meta-analysis aimed at investigating the impact of oral vitamin C supplementation on the post-procedural recovery of orthopedic patients, including functional outcomes and complex regional pain syndrome type I (CRPS I). Literature search using the Medline, Cochrane Library, and Embase databases from inception till March 2021 identified seven eligible randomized controlled trials with 1,361 participants. Forest plot revealed no significant difference in the functional outcomes at 6–12 months [standardized mean difference (SMD) = −0.00, 95% CI − 0.19 to 0.18, 467 patients], risk of overall complications (RR = 0.98, 95% CI 0.68 to 1.39, 426 patients), and pain severity at 3–6 months (SMD = − 0.18, 95% CI − 0.49 to 0.12, 486 patients) between patients with and without oral vitamin C supplementation. Pooled analysis showed that vitamin C treatment reduced the risk of CRPS I regardless of dosage (RR = 0.46, 95% CI 0.25 to 0.85, 1143 patients). In conclusion, the current meta-analysis demonstrated that oral vitamin C supplementation may reduce the risk of complex regional pain syndrome type I but did not improve the functional outcomes in orthopedic patients. Nevertheless, because of the small number of trials included in the present study, further large-scale clinical studies are warranted to support our findings.

Prospective randomized study of the vitamin C effect on pain and complex pain regional syndrome after total knee arthroplasty

PURPOSE

Complex regional pain syndrome (CRPS) type I, formerly known as reflex sympathetic dystrophy (RSD) or algodystrophy, is a condition with chronic pain condition following a trauma or surgery. The physiopathology of this syndrome remained incompletely known. Due to the lack of effective curative treatment, prevention of this complication is important. Therefore, we evaluated the efficacy of vitamin C in preventing this complication.

MATERIAL AND METHODS

Between January 2018 and July 2019, we conducted a prospective randomized study on the efficiency of vitamin C (one group with and one without vitamin C) on prevention of CRPS risk in patients operated in our institution with TKA. Patients with a VAS pain score > 4 performed a three-phase bone scintigraphy. The diagnostic of CRPS was made by using the Budapest criteria associated to a bone scintigraphy. Statistical significance was set at p < 0.05 RESULTS: One hundred fifty-three patients were included in the vitamin C group, 139 in the control group without vitamin C. For the entire cohort, the prevalence of complex regional pain syndrome was 7.9% (23 of 292). The prevalence of complex regional pain syndrome was 3.9% (six of 153) in the vitamin C group and 12.2% (seventeen of 139) in the control group (p = 0.008). After multivariate regression, vitamin C was found to be an independent preventive factor of CRPS and there was a significant difference between the vitamin C group and the control group (relative risk, 0.27; 95% confidence interval, 0.1-0.8; p = 0.015).

CONCLUSION

Taking 1 g per day of vitamin C during 40 days after a TKA reduces the risk of CRPS.

Regional vitamin C in Bier block reduces the incidence of CRPS-1 following distal radius fracture surgery

BACKGROUND

Systemic vitamin C supplementation after wrist fracture has been suggested to reduce the incidence of complex regional pain syndrome (CRPS). This study aimed to evaluate the effect of regional vitamin C in Bier block in the early phase of fracture on CRPS occurrence following surgery for distal radius fractures.

METHODS

Seventy-four patients with isolated extra-articular distal radius fracture with the plan of fixation under Bier block were enrolled. Patients were assigned randomly into two groups: receiving either 500 mg vitamin C or sterile water as a Bier block adjuvant. Both groups received 500 mg of oral vitamin C for six weeks. The patients were evaluated for CRPS signs and symptoms at 2, 4, 6, and 12 weeks post-surgery.

RESULTS

The overall incidence of CRPS 12 weeks after surgery in the vitamin C group was significantly less than the controls (22.9% vs 45.5%, p = 0.04). Logistic regression analysis showed that the only significant contribution in predicting the incidence of CRPS came from the intervention variable (OR 0.26, CI95% 0.08-0.85; P = 0.027).

CONCLUSIONS

The findings suggest that adding vitamin C 500 mg to the local anesthetic in Bier block significantly reduces the incidence of CRPS following distal radius fractures.

The Effect of Perioperative Vitamin C on Postoperative Analgesic Consumption: A Meta-Analysis of Randomized Controlled Trials

Because the analgesic effect of vitamin C against acute pain remains poorly addressed, this meta-analysis aimed at investigating its effectiveness against acute postoperative pain. A total of seven randomized controlled trials with placebo/normal controls were identified from PubMed, Cochrane Library, Medline, Google Scholar, and Embase databases. Pooled analysis showed a lower pain score (standardized mean difference (SMD) = -0.68, 95% CI: -1.01 to -0.36, p < 0.0001; I2 = 57%) and a lower morphine consumption (weighted mean difference (WMD) = -2.44 mg, 95% CI: -4.03 to -0.86, p = 0.003; I2 = 52%) in the vitamin group than that in the placebo group within postoperative 1-2 h. At postoperative 24 h, a lower pain score (SMD = -0.65, 95% CI: -1.11 to -0.19, p = 0.005; I2 = 81%) and lower morphine consumption (WMD = -6.74 mg, 95% CI: -9.63 to -3.84, p < 0.00001; I2 = 85%) were also noted in the vitamin group. Subgroup analyses demonstrated significant reductions in pain severity and morphine requirement immediately (1-2 h) and 24 h after surgery for patients receiving intravenous vitamin C but not in the oral subgroup. These findings showed significant reductions in pain score and opioid requirement up to postoperative 24 h, respectively, suggesting the effectiveness of perioperative vitamin C use. Further large-scale trials are warranted to elucidate its optimal intravenous dosage and effectiveness against chronic pain in the postoperative pain control setting.

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.

On the physiological and cellular homeostasis of ascorbate

Recent interest in the role of ascorbate in crucial metabolic processes is driven by the growing number of medical reports that show beneficial effects of ascorbate supplementation for maintaining general well-being and recovery from a variety of medical conditions. The effect of ascorbate on the local body environment highly depends on its local concentration; at low concentrations it can cause the reduction of reactive oxygen and facilitate activities of enzymes, while at high concentrations it generates free radicals by reducing ferric ions. Ascorbate serving as an electron donor assists the iron-containing proteins and the iron transfer between various aqueous compartments. These functions require effective and adjustable mechanisms responsible for ascorbate biodistribution. In the paper we propose a new biophysical model of ascorbate redistribution between various aqueous body compartments. It combines recent experimental evidence regarding the ability of ascorbate to cross the lipid bilayer by unassisted diffusion, with active transport by well-characterized sodium vitamin C transporter (SVCT) membrane proteins. In the model, the intracellular concentration of ascorbate is maintained by the balance of two opposing fluxes: fast active and slow passive transport. The model provides a mechanistic understanding of ascorbate flux across the epidermal barrier in the gut as well as the role of astrocytes in ascorbate recycling in the brain. In addition, ascorbate passive diffusion across biological membranes, which depends on membrane electric potentials and pH gradients, provides the rationale for the correlation between ascorbate distribution and the transfer of iron ions inside a cell. The proposed approach provides, for the first time, a mechanistic account of processes leading to ascorbate physiological and cellular distribution, which helps to explain numerous experimental and clinical observations.

Safety of vitamin C in sepsis: a neglected topic

PURPOSE OF REVIEW

Although vitamin C is essentially a nontoxic vitamin; however, it is important to be aware regarding the safety of high doses before the wide clinical use.

RECENT FINDINGS

Minor side effects of vitamin C have been reported, many being reported in earlier studies. High doses of vitamin C (up to 1.5 g/kg three times a week as intravenously) were safe in cancer patients with normal renal function and perfect glucose-6-phosphate dehydrogenase activity. As the dose and duration of administration of vitamin C in sepsis are lower and shorter than those used in cancer patients, it seems that it is relatively safe for this population. In ongoing trials, safety of high doses of vitamin C is considered.

SUMMARY

Data regarding the safety of high doses of vitamin C are scant. Until more data become available, caution should be applied in the use of high doses of vitamin C in patients with hemochromatosis, glucose-6-phosphate dehydrogenase deficiency, renal dysfunction, kidney stone, oxaluria, and pediatrics.

Comparison of the effects of preoperative melatonin or vitamin C administration on postoperative analgesia

The analgesic benefit of melatonin and vitamin C as primary or adjuvant agents has been reported in various studies; however, their analgesic effects in the treatment of postoperative pain remain unclear. Thus, we aimed to evaluate the effect of single preoperative dose of oral melatonin or vitamin C administration on postoperative analgesia. In this study, we recruited 165 adult patients undergoing elective major abdominal surgery under general anesthesia. Patients were randomly divided into three equal (n = 55) groups. One hour before surgery, patients received orally melatonin (6 mg) in group M, vitamin C (2 g) in group C, or a placebo tablet in group P. Pain, sedation, patient satisfaction, total morphine consumption from a patient-controlled analgesia device, supplemental analgesic requirement, and the incidence of nausea and vomiting were recorded throughout 24 h after surgery. The mean pain score and total morphine consumption were found significantly lower in both M and C groups compared with group P (p < 0.001). There were no significant differences between group M and C with respect to pain scores (p = 0.117) and total morphine consumption (p = 0.090). Patients requested less supplemental analgesic and experienced less nausea and vomiting in groups M and C compared with group P. In conclusion, preoperative oral administration of 6 mg melatonin or 2 g vitamin C led to a reduction in pain scores, total morphine consumption, supplemental analgesic requirement, and the incidence of nausea and vomiting compared with placebo.

Complex Regional Pain Syndrome: Current Diagnostic and Treatment Considerations

Complex Regional Pain Syndrome is a severe complication of extremity fracture or other injury. Patients who develop this show marked hyperalgesia and allodynia, altered vasomotor, sudomotor and trophic changes. The condition affects women more than men and is most common in those between the ages of 50 and 70 years but can be seen in younger athletes. The diagnosis is made clinically, and treatment is directed at functional recovery using medications, occupational and physical therapy, and psychological interventions. Prognosis for complete recovery is variable and unpredictable.

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

STUDY DESIGN

Prospective cohort study.

INTRODUCTION

Identification of risk factors for CRPS development in patients with surgically treated traumatic injuries attending hand therapy allows to watch at-risk patients more closely for early diagnosis and to take precautionary measures as required.

PURPOSE OF THE STUDY

The aim of this study was to evaluate the risk factors for the development of complex regional pain syndrome (CRPS) after surgical treatment of traumatic hand injuries.

METHODS

In this prospective cohort, 291 patients with traumatic hand injuries were evaluated 3 days after surgery and monitored for 3 months for the development of CRPS. The factors assessed for the development of CRPS were age, sex, manual work, postoperative pain within 3 days measured on a Pain Numerical Rating Scale (0-10), and injury type (crush injury, blunt trauma, and cut laceration injury).

RESULTS

CRPS was diagnosed in 68 patients (26.2 %) with a duration of 40.10 ± 17.01 days between the surgery and CRPS diagnosis. The mean postoperative pain score was greater in patients with CRPS than in those without CRPS (P < .001). Patients with pain scores ≥ 5 had a high risk of developing CRPS compared with patients with pain scores <5 (odds ratio: 3.61, confidence interval = 1.94-6.70). Patients with crush injuries were more likely to develop CRPS (odds ratio: 4.74, confidence interval = 2.29-9.80).

CONCLUSIONS

The patients with a pain score of ≥5 in the first 3 days after surgery and the patients with crush injury were at high risk for CRPS development after surgical treatment of traumatic hand injuries.

LEVEL OF EVIDENCE

II b.

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.

Role of anti-oxidant (vitamin-C) in post-operative pain relief in foot and ankle trauma surgery: A prospective randomized trial

BACKGROUND

Post-operative pain may adversely affect a patient's quality of life. Studies have shown that vitamin C, being an anti-oxidant and neuro-modulating agent, can help to reduce pain in a variety of clinical settings. The objective of this randomized controlled trial was to assess the effectiveness of vitamin C in reducing post-operative pain, analgesia requirements and improving functional outcome.

METHODS

Patients with isolated foot and ankle trauma, who had undergone surgery, were randomly assigned to receive either vitamin C 500mg or a placebo tablet twice a day. VAS score, analgesia requirement and functional outcome were assessed during their regular follow up. Results were compared and analyzed at the end of 3 months.

RESULTS

The group which received vitamin C, showed improvement in VAS score at the end of second and sixth week of follow up, reduced analgesia requirements and improved functional outcome as compared to the placebo group.

CONCLUSIONS

This study shows that the supplementation of vitamin C in patients undergoing surgery for foot and ankle trauma helps to reduce analgesic requirements, improve VAS scores and achieve better functional outcome.

Vitamin C Can Shorten the Length of Stay in the ICU: A Meta-Analysis

A number of controlled trials have previously found that in some contexts, vitamin C can have beneficial effects on blood pressure, infections, bronchoconstriction, atrial fibrillation, and acute kidney injury. However, the practical significance of these effects is not clear. The purpose of this meta-analysis was to evaluate whether vitamin C has an effect on the practical outcomes: length of stay in the intensive care unit (ICU) and duration of mechanical ventilation. We identified 18 relevant controlled trials with a total of 2004 patients, 13 of which investigated patients undergoing elective cardiac surgery. We carried out the meta-analysis using the inverse variance, fixed effect options, using the ratio of means scale. In 12 trials with 1766 patients, vitamin C reduced the length of ICU stay on average by 7.8% (95% CI: 4.2% to 11.2%; p = 0.00003). In six trials, orally administered vitamin C in doses of 1⁻3 g/day (weighted mean 2.0 g/day) reduced the length of ICU stay by 8.6% (p = 0.003). In three trials in which patients needed mechanical ventilation for over 24 hours, vitamin C shortened the duration of mechanical ventilation by 18.2% (95% CI 7.7% to 27%; p = 0.001). Given the insignificant cost of vitamin C, even an 8% reduction in ICU stay is worth exploring. The effects of vitamin C on ICU patients should be investigated in more detail.

The Role of the Peripheral Nerve Surgeon in the Treatment of Pain

Pain is a frequent cause of physician visits. Many physicians find these patients challenging because they often have complicated histories, emotional comorbidities, confusing examinations, difficult problems to fix, and the possibility of factitious complaints for attention or narcotic pain medications. As a result, many patients are lumped into the category of chronic, centralized pain and relegated to pain management. However, recent literature suggests that surgical management of carefully diagnosed generators of pain can greatly reduce patients' pain and narcotic requirements. This article reviews recent literature on surgical management of pain and four specific sources of chronic pain amenable to surgical treatment: painful neuroma, nerve compression, myofascial/musculoskeletal pain, and complex regional pain syndrome type II.

Oxidative Stress Contributes to Fracture/Cast-Induced Inflammation and Pain in a Rat Model of Complex Regional Pain Syndrome

Clinical evidence suggests that vitamin C (Vit C) may protect against the development of complex regional pain syndrome (CRPS) after fracture or surgery. Tibia fracture followed by 4 weeks of cast immobilization (fracture/cast) in rats results in nociceptive, vascular, and bone changes resembling clinical CRPS. In this study, fracture/cast rats were treated with the oxidative stress inhibitors Vit C, N-acetyl cysteine, or 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl to examine their effects on CRPS-related nociceptive and vascular changes. Administration of these agents significantly reduced fracture/cast-induced cutaneous allodynia by 64 to 78%, muscle hyperalgesia by 34 to 40%, and hind limb unweighting by 48 to 89%. Treatments with Vit C and N-acetyl cysteine reduced the oxidative stress markers malondialdehyde in the skin, muscle, and sciatic nerve, and lactate in the gastrocnemius muscle of the fracture/cast limb. Furthermore, Vit C treatment inhibited the post-fracture upregulation of substance P and calcitonin gene-related peptide in the sciatic nerve and the increased expression of the pain-related inflammatory mediators, including interleukin (IL)-6, and nerve growth factor in the skin and IL-1β, and IL-6 in the muscle of the post-fracture/cast limb. These data suggest that oxidative stress may contribute to the nociceptive features of the rat CRPS model.

PERSPECTIVE

Vit C reduced the CRPS-like signs, oxidative stress, and the upregulation of neuropeptide production and inflammatory mediators observed after tibia fracture and casting in rats. Limiting oxidative stress by use of Vit C or alternative strategies could reduce the risk of developing CRPS after surgery or other forms of trauma.

Antioxidant treatment with vitamin C attenuated rotator cuff degeneration caused by oxidative stress in Sod1-deficient mice

Background

Rotator cuff degeneration is 1 of several factors that lead to rotator cuff tears; however, the mechanism of this degeneration remains unclear. We previously reported that deficiency of an antioxidant enzyme, superoxide dismutase 1 (Sod1), in mice induced degeneration in supraspinatus tendon entheses, a model that replicates human rotator cuff degeneration. In this study, we analyzed possible effects of vitamin C (VC), a major antioxidant, on the degenerative changes of supraspinatus entheses in Sod1^−/− mice.

Methods

We administered VC or vehicle, distilled water, for 8 weeks to Sod1^−/− and wild-type male mice beginning at 12 weeks of age (n = 5-8 per group). When mice were 20 weeks of age, we sectioned rotator cuff tissue samples and performed hematoxylin-eosin and toluidine blue staining for quantitative histologic evaluation.

Results

VC administration, compared with vehicle administration, attenuated the histologic changes, including a misaligned 4-layered structure, fragmented tidemark, and toluidine blue staining, in the supraspinatus entheses of Sod1^−/− mice. In the quantitative histologic evaluation, all parameters were significantly decreased in Sod1^−/− mice compared with wild-type mice, except for the number of nonchondrocytes.

Conclusion

We demonstrated that an antioxidant treatment, VC administration, attenuated the rotator cuff degeneration, similar to that observed in humans, that is caused by oxidative stress in Sod1^−/− mice. VC effects included improvements in quantitative histologic parameters and other histologic changes. These results suggest that VC treatment can prevent oxidative stress–induced degeneration of the rotator cuff.

Complex Regional Pain Syndrome Type 1: Diagnosis and Management

Diagnosis of Complex regional pain syndrome (CRPS) is made primarily on a clinical basis, and no specific test is known to confirm or exclude CRPS diagnosis. That is, there aren’t specific diagnostic tools and instrumental tests are made only for identifying an etiology at the basis of the CRPS. Numerous therapeutic methods have been introduced, but none have shown definitive results. When symptoms persist, patients experience permanent impairment and disability. Therefore, early recognition of CRPS, along with proper treatment, is important for minimizing permanent loss of function. As there is no gold standard test for CRPS, several clinical diagnostic criteria have been introduced and applied in various studies. However, to date, no formal or standardized diagnostic criteria for CRPS have been widely accepted. However, the Budapest diagnostic criteria have recently increased in popularity and are frequently used in scientific studies. The goal for management of CRPS is the return of normal limb function. No specific technique has been shown to prevent CRPS following surgery, but avoidance of prolonged immobilization may be important. Therefore, initiating early post-surgical rehabilitation, where possible, is important. A multidisciplinary approach would seem to be optimal, above all things objectives of physical and occupational therapy are fulfilled with combination pharmacotherapy due to provide pain relief to facilitate physical rehabilitation. Future research using large randomized controlled trials should focus on collecting strong evidence for the etiology of CRPS, testing pharmacological effects, and determining appropriate combination treatment strategies.

Complex Regional Pain Syndrome, Current Concepts and Treatment Options

PURPOSE OF REVIEW

Complex regional pain syndrome (CRPS) refers to a chronic pain condition that is characterized by progressively worsening spontaneous regional pain without dermatomal distribution. The symptomatology includes pain out of proportion in time and severity to the inciting event. The purpose of this review is to present the most current information concerning epidemiology, diagnosis, pathophysiology, and therapy for CRPS.

RECENT FINDINGS

In recent years, discovery of pathophysiologic mechanisms of CRPS has led to significant strides in the understanding of the disease process. Continued elucidation of the underlying pathophysiological mechanisms will allow for the development of more targeted and effective evidence-based therapy protocols. Further large clinical trials are needed to investigate mechanisms and treatment of the disorder.

Dietary Vitamin C in Human Health

Vitamin C is essential to prevent scurvy in humans and is implicated in the primary prevention of common and complex diseases such as coronary heart disease, stroke, and cancer. This chapter reviews the latest knowledge about dietary vitamin C in human health with an emphasis on studies of the molecular mechanisms of vitamin C maintenance as well as gene-nutrient interactions modifying these relationships. Epidemiological evidence indicates 5% prevalence for vitamin C deficiency and 13% prevalence for suboptimal status even in industrialized countries. The daily intake (dose) and the corresponding systemic concentrations (response) are related in a saturable relationship, and low systemic vitamin C concentrations in observational studies are associated with negative health outcomes. However, there is no evidence that vitamin C supplementation impacts the risks for all-cause mortality, impaired cognitive performance, reduced quality of life, the development of eye diseases, infections, cardiovascular disease, and cancers. This might be related to the fact that prevention would not be realized by supplementation in populations already adequately supplied through dietary sources. Recent genetic association studies indicate that the dietary intake might not be the sole determinant of systemic concentrations, since variations in genes participating in redox homeostasis and vitamin C transport had been associated with lowered plasma concentrations. However, impact sizes are generally low and these phenomena might only affect individual of suboptimal dietary supply.

Serum vitamin C and spinal pain: a nationwide study

Back pain brings about one of the heaviest burden of disease. Despite much research, this condition remains poorly understood, and effective treatments are frustratingly elusive. Thus, researchers in the field need to consider new hypotheses. Vitamin C (ascorbic acid) is an essential cofactor for collagen crosslinks, a key determinant of ligament, tendon, and bone quality. Recent studies have reported high frequency of hypovitaminosis C in the general population. We hypothesized that lack of vitamin C contributes to poor collagen properties and back pain. We conducted this study to examine the associations between serum concentration of vitamin C and the prevalence of spinal pain and related functional limitations in the adult general population. This study used nationwide cross-sectional data from the U.S. National Health and Nutrition Examination Survey (NHANES) 2003-2004. Data were available for 4742 individuals aged ≥20 years. Suboptimal serum vitamin C concentrations were associated with the prevalence of neck pain (adjusted odds ratio [aOR]: 1.5; 95% confidence interval [CI]: 1.2-2.0), low back pain (aOR: 1.3; 95% CI: 1.0-1.6), and low back pain with pain below knee (aOR: 1.3; 95% CI: 1.0-1.9) in the past 3 months, self-reported diagnosis of arthritis/rheumatism (aOR: 1.4; 95% CI: 1.2-1.7), and related functional limitations' score (adjusted difference of means [aB]: 0.03; 95% CI: 0.00-0.05). The prevalence of hypovitaminosis C in the general population is high. Our study shows associations between vitamin C and spinal pain that warrant further investigation to determine the possible importance of vitamin C in the treatment of back pain patients.

The Efficacy of Vitamin C on Postoperative Outcomes after Posterior Lumbar Interbody Fusion: A Randomized, Placebo-Controlled Trial

Background

Vitamin C has critical features relavant to postoperative pain management and functional improvement; however, no study has yet evaluated the effectiveness of vitamin C on improving the surgical outcomes for spine pathologies. Thus, this study aimed to explore the impact of vitamin C on postoperative outcomes after single-level posterior lumbar interbody fusion (PLIF) for lumbar spinal stenosis in prospectively randomized design. We conducted a 1-year prospective, randomized, placebo-controlled, double-blind study to evaluate the impact of vitamin C on the postoperative outcomes after PLIF surgery.

Methods

A total of 123 eligible patients were randomly assigned to either group A (62 patients with vitamin C) or group B (61 patients with placebo). Patient follow-up was continued for at least 1 year after surgery. The primary outcome measure was pain intensity in the lower back using a visual analogue scale. The secondary outcome measures were: (1) the clinical outcome assessed using the Oswestry Disability Index (ODI); (2) the fusion rate assessed using dynamic radiographs and computed tomography scans; and (3) complications.

Results

Pain intensity in the lower back was significantly improved in both groups compared with preoperative pain intensity, but no significant difference was observed between the 2 groups over the follow-up period. The ODI score of group A at the third postoperative month was significantly higher than the score of group B. After the sixth postoperative month, the ODI score of group A was slightly higher than the score of group B; however, this difference was not significant. The fusion rates at 1 year after surgery and the complication rates were not significantly different between the 2 groups.

Conclusions

Postoperative pain intensity, the primary outcome measure, was not significantly different at 1 year after surgery between the 2 groups. However, vitamin C may be associated with improving functional status after PLIF surgery, especially during the first 3 postoperative months.

Efficacy of vitamin C in preventing complex regional pain syndrome after wrist fracture: A systematic review and meta-analysis

BACKGROUND

Complex regional pain syndrome type I (CRPS-I), previously known as reflex sympathetic dystrophy, is common after conservatively or surgically treated wrist fractures. Several studies support the efficacy of vitamin C in preventing CRPS-I, although the data are somewhat conflicting. The primary objective of this systematic literature review and meta-analysis was to assess the efficacy of vitamin C therapy in preventing CRPS-I after a wrist fracture.

METHODS

Randomised, placebo-controlled trials of vitamin C to prevent CRPS-I after wrist fractures were sought in the three main databases: PubMed (1980 to December 2015), CENTRAL (Central 2015, number 12), and Embase (1980 to December 2015). Two authors worked independently to select articles. Data from selected articles were collected independently.

RESULTS

Three randomised placebo-controlled trials in a total of 875 patients were included. Treatment was non-operative in 758/890 (85.1%) fractures and operative in 132 (14.9%) fractures. Vitamin C supplementation was started on the day of the injury and continued for 50 days. In the group given 500mg of vitamin C daily, the risk ratio for CRPS-I was 0.54 (95%CI, 0.33-0.91; P=0.02). Thus, the risk of developing CRPS-I was significantly decreased by prophylactic treatment with 500mg of vitamin C per day. The heterogeneity rate was 65% (non-significant).

CONCLUSION

Daily supplementation with 500mg of vitamin C per day for 50 days decreases the 1-year risk of CRPS-I after wrist fracture.

LEVEL OF EVIDENCE

II, systematic review of level I and II studies.

The role of vitamin C in the treatment of pain: new insights

The vitamin C deficiency disease scurvy is characterised by musculoskeletal pain and recent epidemiological evidence has indicated an association between suboptimal vitamin C status and spinal pain. Furthermore, accumulating evidence indicates that vitamin C administration can exhibit analgesic properties in some clinical conditions. The prevalence of hypovitaminosis C and vitamin C deficiency is high in various patient groups, such as surgical/trauma, infectious diseases and cancer patients. A number of recent clinical studies have shown that vitamin C administration to patients with chronic regional pain syndrome decreases their symptoms. Acute herpetic and post-herpetic neuralgia is also diminished with high dose vitamin C administration. Furthermore, cancer-related pain is decreased with high dose vitamin C, contributing to enhanced patient quality of life. A number of mechanisms have been proposed for vitamin C’s analgesic properties. Herein we propose a novel analgesic mechanism for vitamin C; as a cofactor for the biosynthesis of amidated opioid peptides. It is well established that vitamin C participates in the amidation of peptides, through acting as a cofactor for peptidyl-glycine α-amidating monooxygenase, the only enzyme known to amidate the carboxy terminal residue of neuropeptides and peptide hormones. Support for our proposed mechanism comes from studies which show a decreased requirement for opioid analgesics in surgical and cancer patients administered high dose vitamin C. Overall, vitamin C appears to be a safe and effective adjunctive therapy for acute and chronic pain relief in specific patient groups.

Adult Complex Regional Pain Syndrome Type I: A Narrative Review

Complex regional pain syndrome type I (CRPS I) is a multifactorial painful disorder with a complex pathogenesis. Both peripheral and central mechanisms are involved. Acute CRPS I is considered to be an exaggerated inflammatory disorder; however, over time, because of altered function of the sympathetic nervous system and maladaptive neuroplasticity, CRPS I evolves into a neurological disorder. This review thoroughly describes the pathophysiological aspects of CRPS I and summarizes the potential therapeutic options. The mechanisms and targets of the treatment are different in the early and late stages of the disease. This current review builds on a previous review by this author group by deepening the role of the peripheral classic and neuronal inflammatory component in the acute stage of this painful disorder.

LEVEL OF EVIDENCE

Not applicable.

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.

The place of occupational therapy in rehabilitation strategies of complex regional pain syndrome: Comparative study of 60 cases

The purpose of the study was to assess the value of combining occupational therapy (OT) with physical therapy (PT) for the rehabilitation of complex regional pain syndrome (CRPS) and to measure its effectiveness on activities of daily life. Sixty patients with CRPS type 1 were recruited and interviewed between September 1, 2014 and February 1, 2015. Thirty patients had undergone PT and thirty had undergone PT+OT. They were administered the short-form of the "Assessment of Life Habits" questionnaire (v.3.0 LIFE-H) created in Canada. This questionnaire consists of 16 items exploring activities of daily living, which were used to compare the effectiveness of the two rehabilitation protocols. The results of each test were submitted to the Wilcoxon test. After confirming the complexity of CRPS in terms of its etiology, clinical signs and progression, rehabilitation was effective, especially for pain. The patients who received PT+OT had on average 10% better dressing and undressing function, 25% better for meal preparation, and 20% better on personal care than those who underwent PT only. In CRPS, OT combined with PT brings a real benefit in restoring the essential activities of daily life. This strategy could be implemented as soon the diagnosis confirmed and continued for a very long time. It helps to avoid the risk of dependence on third parties.

The Pharmacological Management of Complex Regional Pain Syndrome in Pediatric Patients

The awareness of complex regional pain syndrome (CRPS) in the pediatric population is increasing. The condition involves regional pain that is out of proportion to any initiating event (if there is one) and is associated with sensory, functional, autonomic, and inflammatory changes in the region of the pain. The signs and symptoms of CRPS can vary between patients and stage of the disease process. Like many chronic pain conditions, it is often associated with significant disability and a detrimental effect on quality of life. It has a complex pathophysiology that remains poorly understood but provides many potential targets for treatments. Management involves a biopsychosocial formulation that encompasses physical and psychological interventions alongside pharmacological strategies. We review the current evidence for the treatment of this condition in children, with particular reference to pharmacological management.

A simple method for plasma total vitamin C analysis suitable for routine clinical laboratory use

BACKGROUND

In-hospital hypovitaminosis C is highly prevalent but almost completely unrecognized. Medical awareness of this potentially important disorder is hindered by the inability of most hospital laboratories to determine plasma vitamin C concentrations. The availability of a simple, reliable method for analyzing plasma vitamin C could increase opportunities for routine plasma vitamin C analysis in clinical medicine.

METHODS

Plasma vitamin C can be analyzed by high performance liquid chromatography (HPLC) with electrochemical (EC) or ultraviolet (UV) light detection. We modified existing UV-HPLC methods for plasma total vitamin C analysis (the sum of ascorbic and dehydroascorbic acid) to develop a simple, constant-low-pH sample reduction procedure followed by isocratic reverse-phase HPLC separation using a purely aqueous low-pH non-buffered mobile phase. Although EC-HPLC is widely recommended over UV-HPLC for plasma total vitamin C analysis, the two methods have never been directly compared. We formally compared the simplified UV-HPLC method with EC-HPLC in 80 consecutive clinical samples.

RESULTS

The simplified UV-HPLC method was less expensive, easier to set up, required fewer reagents and no pH adjustments, and demonstrated greater sample stability than many existing methods for plasma vitamin C analysis. When compared with the gold-standard EC-HPLC method in 80 consecutive clinical samples exhibiting a wide range of plasma vitamin C concentrations, it performed equivalently.

CONCLUSION

The easy set up, simplicity and sensitivity of the plasma vitamin C analysis method described here could make it practical in a normally equipped hospital laboratory. Unlike any prior UV-HPLC method for plasma total vitamin C analysis, it was rigorously compared with the gold-standard EC-HPLC method and performed equivalently. Adoption of this method could increase the availability of plasma vitamin C analysis in clinical medicine.

Complex Regional Pain Type 1

Complex regional pain syndrome is increasingly recognized in the pediatric population. Owing to the nature of presentation with pain, many of these children present to the emergency setting at different stages of the syndrome with or without numerous prior interactions with health professionals. Complex regional pain syndrome type 1 (CRPS1) is a clinical syndrome characterized by amplified musculoskeletal limb pain that is out of proportion to the history and physical findings, or pain due to non-noxious stimuli (allodynia/hyperalgesia), and accompanied by one or more signs of autonomic dysfunction. Differential diagnosis may include significant trauma (eg, fractures), inflammatory conditions, malignancies, and systemic illness. The diagnosis is clinical. The treatment goals for CRPS1 are restoration of function and relief of pain. Education, physical, and occupational therapy with psychotherapy and defined goals of achievement with reward are the mainstay of treatment for this population. Most children with CRPS1 will have a favorable outcome.

Effect of intravenous ascorbic acid infusion on blood loss during laparoscopic myomectomy: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

Most interventions aimed at reducing bleeding during myomectomy lack sufficient evidence regarding their effectiveness. Recently, it was reported that intraoperative ascorbic acid administration effectively reduced blood loss during abdominal myomectomy. Therefore, this study aimed to investigate whether intravenous ascorbic acid infusion would affect intraoperative blood loss in women undergoing laparoscopic myomectomy.

STUDY DESIGN

A randomized, double-blind, parallel-group, placebo-controlled trial including 50 women undergoing laparoscopic myomectomy was conducted. Women with ≤4 myomas, ≤9cm in maximum diameter were eligible. The study:control group ratio was 1:1. Starting 30minutes before anesthesia, 2g of ascorbic acid or a placebo were administered for 2hours intraoperatively. Intraoperative blood loss, the primary endpoint, was calculated as the difference between the volume of fluids acquired from suction and that used for irrigation of the abdominal cavity during surgery using constant values.

RESULTS

Among the 50 randomized women, 1 and 3 in the study and control groups, respectively, were excluded due to withdrawal of consent, cancelation of surgery, or non-measurement of the primary endpoint. The baseline and operative characteristics were similar between the study and control groups, as was the intraoperative blood loss (193±204mL vs. 159±193mL, P=0.52). In addition, the operating time (95±29min vs. 110±52min; P=0.50) and decrease in hemoglobin level after surgery (1.9±1.31g/dL vs. 1.4±1.4g/dL; P=0.24) were similar between the study and control groups.

CONCLUSIONS

Intravenous ascorbic acid infusion did not reduce intraoperative blood loss in women undergoing laparoscopic myomectomy.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, www.clinicaltrials.gov, NCT01715597.

The Herd Mentality: Strength in Numbers, and Combining Studies

Although clinicians may have the best of intentions in terms of keeping up with the medical literature, the overwhelming volume of published studies and the press of clinical responsibilities can make this difficult. A medical version of the Reader's Digest(©) would thus be a valuable asset. This is something of the role that systematic reviews and meta-analyses play: synthesis and summary of the information in the literature.

Vitamin C to Prevent Complex Regional Pain Syndrome in Patients With Distal Radius Fractures: A Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

To determine whether vitamin C is effective in preventing complex regional pain syndrome (CRPS) in patients with distal radius fractures.

DATA SOURCES

MEDLINE (1946 to present), EMBASE (1974 to present), and The Cochrane Library (no date limit) were systematically searched up to September 6, 2014, using MeSH and EMTREE headings with free text combinations.

STUDY SELECTION

Randomized trials comparing vitamin C against placebo were included. No exclusions were made during the selection of eligible trials on the basis of patient age, sex, fracture severity, or fracture treatment.

DATA EXTRACTION

Two reviewers independently screened articles, extracted data, and applied the Cochrane Risk of Bias tool. Evidence was graded using the Grading of Recommendations Assessment, Development, and Evaluation approach.

DATA SYNTHESIS

Heterogeneity was quantified using the χ test and the I statistic. Outcome data were combined with a random effects model.

RESULTS

Across 3 trials (n = 890) of patients with distal radius fractures, vitamin C did not reduce the risk for CRPS (risk ratio = 0.45; 95% confidence interval, 0.18-1.13; I = 70%). This result was confirmed in sensitivity analyses to test the importance of missing data because of losses to follow-up under varying assumptions. Heterogeneity was explained by diagnostic criteria, but not regimen of vitamin C or fracture treatment.

CONCLUSIONS

The evidence for vitamin C to prevent CRPS in patients with distal radius fractures fails to demonstrate a significant benefit. The overall quality of the evidence is low, and these results should be interpreted in the context of clinical expertise and patient preferences.

Complex regional pain syndrome

Complex regional pain syndrome is an uncommon chronic pain condition. It develops spontaneously or following an injury. The features are limb pain, allodynia, hypersensitivity, hyperalgesia, abnormalities of the vasomotor, sudomotor and motor systems, and trophic changes, with reduced use of the affected limb. The diagnosis is clinical and one of exclusion. The emphasis of therapy is graded rehabilitation and movement of the limb with physiotherapy and occupational therapy. Psychological therapies should be offered if a patient is making no or slow progress in the acute phase, and to all patients in the chronic phase as depression can occur. The goal of pharmacotherapy is to assist functional improvement. The early phase may be managed with simple analgesia. Antineuropathic drugs including tricyclic antidepressants and antiepileptic drugs may be added. Other treatments with some evidence of effectiveness include corticosteroids, calcitonin and bisphosphonates. Vitamin C has been used for primary prevention after wrist fracture and upper and lower limb surgery. There is no evidence that it is effective for treating established complex regional pain syndrome.

Bee venom pharmacopuncture: an effective treatment for complex regional pain syndrome

Objectives:

Treating complex regional pain syndrome (CRPS) is difficult because it still does not have a recommended therapy. A 29-year-old man was diagnosed with CRPS after surgery on his 4^th and 5^th left toes 7 years ago. Though he had undergone diverse pain treatment, the symptoms persisted, so he visited Dunsan Korean Medicine Hospital of Daejeon University. This case report presents results on the effect of bee venom pharmacopuncture in treating patient with CRPS.

Methods:

Bee venom pharmacopuncture (BVP), 0.15 to 0.4 mL dosage, was administered at GB43. The treatment was applied each week for a total 14 times. The symptoms were evaluated using a numeric rating scale (NRS) and the dosage of pain medicine.

Results:

On the first visit, he was taking an anticonvulsant, a trycyclic antidepressant, and an analgesic. On the NRS the worst pain in the toes received a score of 8. He also complained of severe pain and hypersensitivity when the 4^th and the 5^th toes were touched just slightly. Other complaint included dyspepsia, rash, and depression. After treatment, on the NRS, the score for toe pain was 0, and he no longer needed to take pain medication. During the 4-months follow-up period, he has remained without pain; neither have additional symptoms appeared nor adverse events occurred.

Conclusion:

BVP may have potential benefits for treating patients with CRPS.

Algodystrophy (CRPS) in minor orthopedic surgery

Algodystrophy or Chronic Regional Pain Syndrome (CRPS) is a painful disorder that develops especially at upper or lower extremities of the limbs after a fracture. This syndrome is probably due to bone microvascular changes with subsequent sympathetic nervous system involvement. The pain that characterizes CRPS is spontaneous, disproportionate to the traumatic event and is associated with hyperalgesia, and a variety of autonomic and trophic disorders. This condition has a variable incidence up to 37% of the cases, increasing along with the severity of the fracture. CRPS has a higher chance of developing in women, in older individuals, in smokers, and in patients with reduced bone strength. Early diagnosis is associated with remission in 80-90% of cases. Since the typical onset of the disease is insidious over 2 weeks after surgery, a diagnostic and therapeutic delay may occur. These are the major causes of a high percentage of chronic and disabling complications leading to impaired functional outcomes. In the acute or subacute phase, infusion of bisphosphonates has proven to be the first-choice of treatment with a high percentage of remissions. Moreover, it has been suggested the utility of vitamin C in prevention of CRPS. Furthermore, in the chronic phase electroanalgesia seems to provide promising results.