Cost-Effectiveness and Cost-Utility Analysis of Spinal Cord Stimulation in Patients With Failed Back Surgery Syndrome: Results From the PRECISE Study

Objective

To assess the cost‐effectiveness and cost‐utility of Spinal Cord Stimulation (SCS) in patients with failed back surgery syndrome (FBSS) refractory to conventional medical management (CMM).

Materials and Methods

We conducted an observational, multicenter, longitudinal ambispective study, where patients with predominant leg pain refractory to CMM expecting to receive SCS+CMM were recruited in 9 Italian centers and followed up to 24 months after SCS. We collected data on clinical status (pain intensity, disability), Health‐Related Quality‐of‐Life (HRQoL) and on direct and indirect costs before (pre‐SCS) and after (post‐SCS) the SCS intervention. Costs were quantified in € 2009, adopting the National Health Service's (NHS), patient and societal perspectives. Benefits and costs pre‐SCS versus post‐SCS were compared to estimate the incremental cost‐effectiveness and cost utility ratios.

Results

80 patients (40% male, mean age 58 years) were recruited. Between baseline and 24 months post‐SCS, clinical outcomes and HRQoL significantly improved. The EQ‐5D utility index increased from 0.421 to 0.630 (p < 0.0001). Statistically significant improvement was first observed six months post‐SCS. Societal costs increased from €6600 (pre‐SCS) to €13,200 (post‐SCS) per patient per year. Accordingly, the cost‐utility acceptability curve suggested that if decision makers' willingness to pay per Quality‐Adjusted‐Life‐Years (QALYs) was €60,000, SCS implantation would be cost‐effective in 80% and 85% of cases, according to the NHS's and societal point of views, respectively.

Conclusions

Our results suggest that in clinical practice, SCS+CMM treatment of FBSS patients refractory to CMM provides good value for money. Further research is encouraged in the form of larger, long‐term studies.

Appropriate referral and selection of patients with chronic pain for spinal cord stimulation: European consensus recommendations and e-health tool

Background

Spinal cord stimulation (SCS) is an established treatment for chronic neuropathic, neuropathic‐like and ischaemic pain. However, the heterogeneity of patients in daily clinical practice makes it often challenging to determine which patients are eligible for this treatment, resulting in undesirable practice variations. This study aimed to establish patient‐specific recommendations for referral and selection of SCS in chronic pain.

Methods

A multidisciplinary European panel used the RAND/UCLA Appropriateness Method (RUAM) to assess the appropriateness of (referral for) SCS for 386 clinical scenarios in four pain areas: chronic low back pain and/or leg pain, complex regional pain syndrome, neuropathic pain syndromes and ischaemic pain syndromes. In addition, the panel identified a set of psychosocial factors that are relevant to the decision for SCS treatment.

Results

Appropriateness of SCS was strongly determined by the neuropathic or neuropathic‐like pain component, location and spread of pain, anatomic abnormalities and previous response to therapies targeting pain processing (e.g. nerve block). Psychosocial factors considered relevant for SCS selection were as follows: lack of engagement, dysfunctional coping, unrealistic expectations, inadequate daily activity level, problematic social support, secondary gain, psychological distress and unwillingness to reduce high‐dose opioids. An educational e‐health tool was developed that combines clinical and psychosocial factors into an advice on referral/selection for SCS.

Conclusions

The RUAM was useful to establish a consensus on patient‐specific criteria for referral/selection for SCS in chronic pain. The e‐health tool may help physicians learn to apply an integrated approach of clinical and psychosocial factors.

Significance

Determining the eligibility of SCS in patients with chronic pain requires careful consideration of a variety of clinical and psychosocial factors. Using a systematic approach to combine evidence from clinical studies and expert opinion, a multidisciplinary European expert panel developed detailed recommendations to support appropriate referral and selection for SCS in chronic pain. These recommendations are available as an educational e‐health tool (https://www.scstool.org/).

Chronic pain therapy and hypothalamic-pituitary-adrenal axis impairment

Opiates and/or nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most effective therapies for chronic pain, but their prolonged time of use can affect health conditions through physical and psychological side effects. They include the very common gastrointestinal effects and changes that can induce osteoporosis, depression, impaired cognition and a generally poor quality of life, which per se can induce and maintain a chronic painful condition. For this reason it is becoming imperative to expand our knowledge of the interaction of these substances with body functions apparently not directly involved in nociception and pain, such as neuroendocrine functions. The purpose of this study was to determine, in male and female patients suffering from chronic pain, the effect of conventional pain therapy (opiates, NSAIDs) on hypothalamic-pituitary-adrenal (HPA) axis function. This was assessed by measuring the blood levels of adrenal-related hormones (adrenocorticotrophin hormone, ACTH; cortisol; dehydroepiandrosterone, DHEA and dehydroepiandrosterone sulfate, DHEAS). The second purpose of the study was to test the hypothesis that these hormones are associated with the psychological profile shown by the chronic pain patients. The results showed significant changes induced by pain therapy on the HPA axis: ACTH, cortisol, DHEA and DHEAS blood levels decreased in all subjects taking opiates or NSAIDs to treat pain. Moreover these changes showed significant correlations with psychological features of the subjects depending on age and sex.

Treatment options in postherpetic neuralgia

Postherpetic neuralgia (PHN) is a separate disease entity that represents a complication of acute herpes zoster. PHN, involving aberrant somatosensory processing in the peripheral and/or central nervous system, is considered to be a chronic neuropathic pain, frequently unresponsive to all treatment modalities. Despite the clinical trial data demonstrating successful pain relief with several drug regimens, the pharmacologic management of neuropathic pain is difficult, particularly in PHN. Response to therapy is generally inhomogeneous. Some patients experience long-term pain control with either topical or oral monotherapy with antidepressants, anticonvulsants, or opioids. Other PHN patients, such as those suffering pain due to central nervous system lesions, are extraordinarily refractory to all measures. This article will review current treatments--tricyclic antidepressants, anticonvulsants, local anesthetics, clonidine, N-methyl-D-aspartate (NMDA)-antagonists, and opioids and focus on mechanism-based pharmacologic interventions. Pharmacologic approaches can be classified into three groups: 1) drugs that act topically in the affected skin area; 2) drugs that act on nerve excitability and conduction in sensory axons; and 3) drugs that act on neural damage related synaptic changes. This last group is the only pain treatment option related to central denervation. To date, the treatment of PHN has relied on the use of tricyclic antidepressants (TCAs), which represent the most comprehensively studied medications for this pain syndrome. Clinical data indicate that TCAs are effective analgesics in approximately 50% of patients; these drugs have been recommended as first-line agents for all neuropathic pain syndromes except trigeminal neuralgia, but are frequently contraindicated or poorly tolerated in elderly patients with PHN. If monotherapy fails, a mechanism- and/or symptom-based multidrug regimen can be used. There is also consistent support for intravenous and topical lidocaine, intravenous ketamine, carbamazepine, and opioids. Gabapentin, a new anticonvulsant, can be considered a first-line oral medication for PHN based on the efficacy and safety results of a recently completed double-blind trial. In addition to positive effects on PHN, sleep, mood, and overall quality of life were significantly improved.

Inhibition of Somatosensory Evoked Potentials During Different Modalities of Spinal Cord Stimulation: A Case Report

BACKGROUND

Although the number of patients with chronic neuropathic pain treated by spinal cord stimulation (SCS) is continuously increasing, its analgesic mechanism remains to be elucidated. Previous studies have demonstrated that classical SCS (low stimulation frequency evoking paresthesia) inhibits the somatosensory evoked potentials (SEPs).

CASE PRESENTATION

We describe here the results of a series of SEPs recordings performed in a female patient with chronic pain, using four different types of SCS: the classical SCS (60 Hz, 250 μsec) and three paresthesia free SCS modalities: high frequency (10 kHz, 20 μsec) and two types of high-density SCS (500 Hz, 500 μsec and 200 Hz, 1000 μsec). All the tested SCS modalities completely inhibited the SEPs cortical responses, with an immediate recovery of the inhibition after turning the stimulator off.

CONCLUSIONS

All the tested SCS modalities are able to inhibit SEPs and thus the lemniscal system. In particular, both paresthesia and paresthesia free SCS affect SEPs in the same manner. The presence of this inhibitory effect during paresthesia free modalities suggests that it is independent from the generation of action potentials, with a probable mechanism acting at the stimulation site. Further studies investigating the relationship between the inhibition of the lemniscal system and the analgesic effect of the SCS are, therefore, warranted.

Comparison of Tonic vs. Burst Spinal Cord Stimulation During Trial Period

BACKGROUND

Spinal cord stimulation (SCS) is a well-known treatment in patients with failed back surgery syndrome (FBSS). Burst stimulation is a recently developed stimulation modality that seems to be superior to tonic stimulation.

METHODS

This observational multicenter study compared tonic and burst stimulation during a trial period in patients with FBSS or radiculopathy. All the patients enrolled underwent two weeks of tonic stimulation followed by another two weeks of BurstDR stimulation, without randomization. The primary outcome was the reduction of pain in the legs and back. Health-related quality of life (EQ-5D) and the pain catastrophizing scale (PCS) were assessed before and after the trial. Patients were reevaluated after 12 months.

RESULTS

We recruited 23 patients, 57% of whom had FBSS and 43% had radiculopathies. Five patients failed both the tonic and burst stimulation trials. While tonic stimulation reduced leg pain (p < 0.05), the burst mode added an extra pain reduction (ΔNRS 1.2 ± 1.5) (p < 0.01). No significant reduction in back pain was found (p 0.29). Pain on movement was reduced only by BurstDR (p < 0.01). Both stimulation modalities increased EQ-5D and reduced PCS from the baseline (p < 0.0001). At the end of the SCS trial phase, 26% patients chose tonic SCS, while 74% preferred burst. On 12-month follow-up examination, the benefits recorded at the end of the trial were maintained.

CONCLUSIONS

Burst stimulation confers a greater reduction in leg pain intensity at rest and on movement. Reducing axial pain is still a challenge. Further studies are needed in order to provide each patient with the most appropriate stimulation paradigm.

Genicular Nerve Pulsed Dose Radiofrequency (PDRF) Compared to Intra-Articular and Genicular Nerve PDRF in Knee Osteoarthritis Pain: A Propensity Score-Matched Analysis

Background

Chronic knee osteoarthritic (OA) pain is a common and debilitating complaint in elderly patients. Despite numerous pharmaceutical options, the majority of patients still experience long-term pain. Genicular nerve (GN) radiofrequency has become increasingly popular as a treatment for knee pain. This retrospective study aimed to evaluate the effects of pulse dose radiofrequency (PDRF) in patients with chronic knee OA pain.

Patients and Methods

Propensity score matching analysis was performed in a retrospective cohort of 78 patients with moderate-severe knee OA pain unresponsive to conservative treatment who underwent PDRF GN or intra-articular (IA) and PDRF GN. Pain relief was measured using the numeric rating scale (NRS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Patient Global Impression of Change (PGIC) at 3 and 6 months post-intervention.

Results

A significant reduction in NRS scores was reported at 3 (p<0.001) and 6 months (p<0.001) after PDRF in both groups. NRS was lower in PDRF IA + GN than PDRF GN (p<0.0001). WOMAC pain was significantly reduced at 3 months in PDRF IA + GN group (baseline: 10.12±3.14, 3 months: 6.25±2.44, p=0.0001). WOMAC stiffness and function were improved only at 3 months in PDRF IA + GN compared to baseline (p=0.007 and p=0.006, respectively). A longer period of pain relief was reported after PDRF IA + GN (6.75±2.42 months) compared to PDRF GN (4.31±2.85 months, p<0.001) in association with higher PGIC scores.

Conclusion

This is the first study that compared two different PDRF techniques. PDRF GN and PDRF IA + GN were both effective in reducing pain at 3 and 6 months follow-up. However, only PDRF IA + GN was able to improve WOMAC scores at 3 months after the treatment with a longer period of efficacy compared to PDRF GN alone.

Applicability and Validity of an e-Health Tool for the Appropriate Referral and Selection of Patients With Chronic Pain for Spinal Cord Stimulation: Results From a European Retrospective Study

OBJECTIVES

To support rational decision-making on spinal cord stimulation (SCS), a European expert panel developed an educational e-health tool using the RAND/University of California at Los Angeles Appropriateness Method. This retrospective study aimed to determine the applicability and validity of the tool using data from patients for whom SCS had been considered.

MATERIALS AND METHODS

A total of 12 European implant centers retrieved data from 25 to 50 consecutive patients for whom SCS was considered in 2018-2019. For each patient, data were captured on the clinical and psychosocial variables included in the e-health tool, center decisions on SCS, and patient outcomes. Patient outcomes included global perception of effect by the patient and observer, and pain reduction (numeric pain rating scale) at six-month follow-up.

RESULTS

In total, 483 patients were included, of whom 133 received a direct implant, 258 received an implant after a positive trial, 32 had a negative trial, and 60 did not receive SCS for reasons other than a negative trial. The most frequent indication was persistent spinal pain syndrome type 1 and type 2 (74%), followed by neuropathic pain syndromes (13%), complex regional pain syndrome (12%), and ischemic pain syndromes (0.8%). Data on the clinical and psychosocial variables were complete for 95% and 93% of patients, respectively, and missing data did not have a significant impact on the study outcomes. In patients who had received SCS, panel recommendations were significantly associated with patient outcomes (p < 0.001 for all measures). Substantial improvement ranged from 25% if the e-health tool outcome was "not recommended" to 83% if SCS was "strongly recommended". In patients who underwent a trial (N = 290), there was 3% of trial failure when SCS was "strongly recommended" vs 46% when SCS was "not recommended".

CONCLUSIONS

Retrospective application of the e-health tool on patient data showed a strong relationship between the panel recommendations and both SCS trial results and treatment outcomes.

Patient selection for spinal cord stimulation: The importance of an integrated assessment of clinical and psychosocial factors

BACKGROUND

A previously developed educational e-health tool considers both clinical and psychosocial factors when selecting patients with chronic pain for spinal cord stimulation (SCS). The validity of the composite recommendations was evaluated in a retrospective study, demonstrating a strong relationship with patient outcomes after SCS.

METHODS

An additional retrospective analysis was performed to determine the added value of a psychosocial evaluation as part of the decision-making process on SCS. Data concerned 482 patients who were considered for SCS in 2018-2019. Analysis focused on the relationship between the different layers of the tool recommendations (clinical, psychosocial, composite) with trial results and patient outcomes at 6 months after SCS. Of the initial study population, 381 patients underwent SCS and had follow-up data on at least one of three pain-related outcome measures.

RESULTS

Pain improvement was observed in 76% of the patients for whom SCS was strongly recommended based on merely the clinical aspects. This percentage varied by the level of psychosocial problems and ranged from 86% in patients without any compromising psychosocial factors to 60% in those with severe problems. Similarly, the severity of psychosocial problems affected trial results in patients for whom SCS was either recommended or strongly recommended.

CONCLUSIONS

The strong relationship between psychosocial factors embedded in the SCS e-health tool and patient outcomes supports an integrated and multidisciplinary approach in the selection of patients for SCS. The educational e-health tool, combining both clinical and psychosocial aspects, is believed to be helpful for further education and implementation of this approach.

Long-term safety of spinal cord stimulation systems in a prospective, global registry of patients with chronic pain

Aim: The availability of long-term (>2 years) safety outcomes of spinal cord stimulation (SCS) remains limited. We evaluated safety in a global SCS registry for chronic pain. Methods: Participants were prospectively enrolled globally at 79 implanting centers and followed out to 3 years after device implantation. Results: Of 1881 participants enrolled, 1289 received a permanent SCS implant (1776 completed trial). The annualized rate of device explant was 3.5% (all causes), and 1.1% due to inadequate pain relief. Total incidence of device explantation >3 years was 7.6% (n = 98). Of these, 32 subjects (2.5%) indicated inadequate pain relief as cause for removal. Implant site infection (11 events) was the most common device-related serious adverse event (<1%). Conclusion: This prospective, global, real-world study demonstrates a high-level of safety for SCS with low rate of explant/serious adverse events. Clinical Trial Registration: NCT01719055 (ClinicalTrials.gov).

Effect of Botulinum Toxin on Disabling Neuropathic Pain: A Case Presentation Suggesting a New Therapeutic Strategy

This case presentation describes a 47-year-old woman who developed complex regional pain syndrome type II with severe neuropathic pain following iatrogenic transection of the tibial nerve at the ankle. The pain and disability progressively worsened over time, markedly impaired ambulation, and were not relieved despite various analgesic treatments. After injection of botulinum toxin (abobotulinumtoxinA, BoNT-A) in the leg muscles the tendons of which pass through the tarsal tunnel (together with the tibial nerve), her pain decreased and her walking capacity improved. This case suggests a new therapeutic role for botulin toxin in treating peripheral neuropathic pain caused by movement-evoked ectopic potentials.

LEVEL OF EVIDENCE

V.

Quantitative Sensory Testing (QST) Estimation of Regional Cutaneous Thermal Sensitivity During Waking State, Neutral Hypnosis, and Temperature Specific Suggestions

This study aimed to determine the effects of neutral hypnosis and hypnotic temperature suggestions in thermal and pain thresholds compared to resting state. Sixteen healthy medium or high hypnotizable volunteers were enrolled. Hypnotizability was assessed with the Hypnotic Induction Profile (HIP); QST was checked in resting state, in neutral hypnosis, after suggestions of heat and cold, and after deinduction. A significant increase in heat threshold was recorded during hypnosis with both cold and heat suggestions compared to neutral hypnosis. HIP induction score showed a linear correlation with changes of temperature thresholds after heat and cold suggestions. Thermal suggestions may result in a significant increase of heat perception thresholds with respect to neutral hypnosis. HIP score is related to thermal threshold changes. QST is a valuable and manageable tool to measure temperature threshold change during hypnosis.

Dynamic Mechanical Allodynia--One Clinical Sign, Several Mechanisms: Five Illustrative Cases

Pain evoked by tangential movement across the skin is usually defined as dynamic mechanical allodynia (DMA). Some patients complain of DMA as troublesome as spontaneous pain and refer a marked interfering with activities of daily living and sleep. Pathophysiology of DMA is complex and can be related to several mechanisms, both nociceptive and neuropathic. Five exemplificative clinical cases of DMA are presented, each associated to a possible specific mechanism: injured skin DMA, peri-injured skin DMA, far injury DMA, nerve-confined DMA and fear DMA (pseudo allodynia). The identification of these subcategories of DMA can stimulate further studies aimed at evaluating the usefulness of a mechanism-based therapy for the different clinical forms of DMA.

Retrogasserian radiofrequency thermocoagulation: A repeatable treatment in trigeminal neuralgia unresponsive to drug therapy

Background:

Trigeminal neuralgia present an incidence rates ranging between 5.9 and 12.6 per 100.000 persons; although not frequent, it is a pathology often characterized by intense pain, an extremely significant reduction in quality of life and medical therapy is not always effective or tolerated. In these cases, the patient can undergo interventional treatments including radiofrequency thermocoagulation. There are still doubts regarding the effectiveness over time, the injury parameters and the repeatability of the procedure.

Materials and Methods:

We analyze patients with trigeminal pain undergo retrogasserian radiofrequency in a single center over a period of 8 years. The procedure was performed with the following parameters: Lesion time 60 sec, lesion temperature 70°C for first thermolesion 72°C for subsequent thermolesions. Duration of benefit, number of repetitions of the maneuver, and incidence of adverse events were assessed.

Results:

Totally, 122 patients with essential trigeminal neuralgia and 20 patients with trigeminal neuralgia secondary to multiple sclerosis were analyzed; almost all patients (96.5%) showed a significant reduction in pain after one or more procedures over time; 96.5 of the patients showed excellent pain relief after 1 (40%) or more procedures (60%). The average time between one procedure and the next was 26 months.

Conclusion:

The use of time and temperature parameters chosen shows excellent efficacy, in line with the literature, with very low incidence of adverse events. The pain-free time between one procedure and the next does not seem to be a significant prognostic criterion which may or may not indicate the repetition of the procedure.

Pain diagnosis and treatment according to the pain generating factors

Chronic pain impacts on many aspects of patient life affecting autonomy, sleep, social activities and also employment. Adequate pain control is often challenging in patients with chronic pain, despite the availability of many medications and interventional techniques. Limitations to successful pain treatment are the poor understanding of contributing mechanisms and the lack of a mechanism based approach in clinical practice. The purpose of this article is to identify the factors contributing to pain generation in order to guide a personalized treatment. We analyze tissue specificity for chemical and physical stresses potentially causing pain, the changes that occur in the peripheral and central pain pathways during disease, the stimuli that, acting on a pathological pain pathway, can trigger pain. The pain generating factors should be recognized in each patient and addressed with pharmacological, rehabilitation and invasive interventions.

Amitriptyline-perphenazine therapy for persistent idiopathic facial pain: translational perspectives from a retrospective study

BACKGROUND

Persistent idiopathic facial pain (PIFP) can be challenging, both in its diagnosis, which appears to be purely exclusionary, and in its treatment, which currently lacks a gold standard. Amitriptyline is considered a first-line therapy, although not always effective. Recent insights into the role of dopamine in facial pain suggest that a novel therapeutic approach could target the dopamine system.

METHODS

This study aimed to retrospectively evaluate the efficacy of treatment with amitriptyline-perphenazine association in patients with severe PIFP. Thirty-one patients were given a regimen dose of amitriptyline-perphenazine at dosages ranging between 10/2 and 20/4 mg and were then retrospectively analyzed. We evaluated the following outcomes, referred to the last week prior to follow-up visits: NRS score for pain intensity (minimum, maximum, and average), the number of attacks, and SF-36 questionnaire for quality of life. Comparisons were made between pre- and post-treatment.

RESULTS

Thirty-one patients over 35 were screened. At baseline, average NRS was 5 ± 0.93 (CI 95%: 4.6-5.3), and the median number of breakthrough episodes over last week was 5 ± 1.57 (CI 95%: 4-6) with a maximum NRS = 9 ± 0.89 (CI 95%: 8-9). After treatment, average NRS was 4.1 ± 0.93 (CI 95%: 3.8-4.5; p < 0.001), maximum NRS was 6.1 ± 1.60 (CI 95%: 5.5-6.6), and the median number of attacks was 4 ± 0.99 (IC 95%: 3-4) (p < 0.001). Regarding SF-36 questionnaire, the most improved parameters were quality of life related to pain (25.89 ± 12.48 vs 31.19 ± 13.44; p < 0.001) and physical function (69.56 ± 17.84 vs 84.17 ± 20.99; p < 0.001).

CONCLUSION

Despite limitations, the pain scores, the frequency of the attacks, and quality of life were found to be significantly improved after treatment. Although results are not broad based given the small sample size, the combination of amitriptyline and perphenazine may be an effective and well-tolerated treatment in patients with PIFP. It is abundantly clear that dopaminergic pathways play a key role in pain modulation, yet the underlying mechanisms have not been fully understood, requiring further investigation.

Radiofrequency stimulation of the dorsal root ganglion as a diagnostic tool for radicular pain syndromes: six representative cases

BACKGROUND

We discuss the diagnostic benefit of pulsed radiofrequency (PRF) of the dorsal root ganglion (DRG) in a case series of patients with different pathologies. We expand the diagnostic potential of DRG stimulation beyond paresthesia mapping by using DRG stimulation to help determine the role of the DRG in the patient's pain and narrow down the etiology. In some cases, DRG stimulation was also part of the treatment plan.

METHODS

Six patients underwent DRG radiofrequency as a diagnostic/therapeutic step before considering implantation of a DRG neurostimulator. First, patients underwent a basic bedside neurological evaluation. Next, an electrode was placed in the epidural space through the sacral hiatus or between vertebral laminae. Then, sensory stimulation was applied at 50 Hz and gradually increased from 0.1 V until the patient reported paresthesia or until a maximum intensity of 2 V was reached. Patients were asked to describe where the stimulation was felt and outline the anatomical area the paresthesia covered. Then a motor stimulation was applied at 2 Hz until muscle twitching was reported by the patient or observed by the physician.

RESULTS

The information obtained helped diagnose the type of lesion as principally preganglionic, ganglionic, or postganglionic. This information guided patient management.

CONCLUSION

PRF of the DRG can provide valuable diagnostic information and is a useful step before ganglionic electrode implantation. In all cases, PRF of the DRG provided valuable diagnostic information and guided management options.

Chronic pain: not only a matter of time

The term "chronic" is often used in daily clinical practice to indicate a type of pain that lasts over time and is accompanied by diagnostic and therapeutic difficulties. The common feeling is that in this category are actually collected many different clinical cases with the unique characteristic that the pain lasts a long time. It follows that treatment failures are common and patients roam from doctor to doctor in search of an effective care program. At the same time the health spending for the treatment of these patients is becoming increasingly high. In clinical practice we meet many patients with obscure pain syndromes which are classified as "chronic" and untreatable only because persist for long time and that obtain a complete pain relief after a right diagnosis and a specific treatment. In this review the Authors want to argue that the term chronic should not be used only when the pain persists for some time or just when signs and symptoms of mechanisms in the central nervous systems are present. The authors suggest that there is a clear difference between acute and chronic pain but also that in chronic pain patients there are three different painful conditions: 1) patients with a chronic disease (or sequelae) and with chronic pain in which the pain mechanisms are closely related to the underlying chronic disease (e.g., rheumatoid arthritis) or to previous injury that has generated other unsolvable mechanisms (e.g., deafferentation pain after plexus avulsion); 2) patients with a chronic disease and chronic pain in which new mechanisms overlap those related to the underlying disease; 3) patients with chronic pain in whom the correlation between pain and the initial tissue injury is lost and the persistence of pain is due to new developed mechanisms. According to this classification we can distinguish patients with "painful chronic disease" by patients with "independent chronic pain". In these latter cases the complexity of the clinical picture is to be found in a maladaptative response to pain, in emergence of central nervous system mechanisms and in behavioral changes that, in turn, can cause long-term social, psychological and physical sequelae. Differences among patients in developing chronic pain can be related to differences in the ability of the brain to continuously adapt its functional and structural organization. It is obvious that the care plan for these complex patients is profoundly different from that needed for patients with pain linked to a chronic disease or stabilized pain mechanisms. The purpose of the present article is to provide a review of the most noteworthy developments in this field and to propose some observations that may help to understand this pain condition and the patients.

[Validation of the Italian version of the "Neuropathic Pain Scale" and its clinical applications]

BACKGROUND

The Neuropathic Pain Scale is the first specific tool to measure and analyse pain due to a lesion in the nervous system; this kind of pain is usually difficult to describe for the patient because it is characterized by unusual qualities. Aim of this study is to evaluate a possible relation between pain descriptions and underlying pathogenetic mechanisms.

METHODS

The Italian version of the Neuropathic Pain Scale has been administered to 145 patients with neuropathic pain due to chronic radiculopathy, diabetic neuropathy, post-traumatic neuropathy, Complex Regional Pain Syndrome or postherpetic neuralgia. As it has been done in Galer's study, the predictive validity and the items' correlation have been evaluated; moreover, the structure validity of the scale has been studied.

RESULTS

Pain values were high in all pain syndromes with the prevalence of certain items in particular pathologies. The correlation of some items with "deep pain" and others with "superficial pain" was also observed.

CONCLUSIONS

The results have confirmed the statistical validity of the Italian version of the scale; they also pointed out the usefulness of the scale to distinguish between superficial pain, typical of neuropathic pain, and deep pain, typical of somatic pain.

Feasibility of therapeutic music listening in fibromyalgia: a randomised controlled pilot study

BACKGROUND

Fibromyalgia patients can benefit from music approaches as complementary treatments. In the literature, it was shown that these interventions managed pain conditions as well as reduced complaints, increased relaxation, and improved moods.

OBJECTIVE

This study aimed at evaluating music therapy, in the form of therapeutic music listening, specifically for patients with fibromyalgia, to treat chronic pain by reducing pain perception, increasing well-being, and improving quality of life.

METHODS

Twenty-four patients with fibromyalgia were recruited to take part in this feasibility pilot study that adopted a between-subject and within-subject design. Participants were randomised into three groups: (1) standard care, (2) standard care plus preferred music listening, (3) standard care plus Melomics-Health music listening, composed by an algorithm. Participants in experimental groups listened to 30 min of music at home, twice a day for a month. Patients' perceptions of changes following the listening, the intensity of pain and its interference in their lives, physical and mental well-being, and reported attitudes towards listening to music were evaluated respectively through the patients' global impression of change, the brief pain inventory, the Short Form Healthy Survey-12, and the cognitive behavioural assessment-outcome evaluation.

RESULTS

The study showed that music listening can significantly affect mental well-being compared to no music. Moreover, the effects in the Melomics-Health group are maintained at follow-up. No significant effect on pain perception was noted.

CONCLUSIONS

The study provides information supporting a possible role of music listening in improving well-being of patients with fibromyalgia.