Pretreatment Psychosocial Variables as Predictors of Outcomes Following Lumbar Surgery and Spinal Cord Stimulation: A Systematic Review and Literature Synthesis

Patient selection for spinal cord stimulators: mental health perspective

Research has shown that psychosocial factors can predict poor outcome for spinal cord stimulation (SCS) for patients with chronic pain, substantiating the need for standardized assessment techniques to incorporate psychosocial factors in patient selection. Presurgical psychological assessment is often required for SCS. Best practices include clinical interviews by psychologists and use of standardized measures of psychosocial risk factors. Psychologists should assess mental health and social risk factors, as well as an individual's understanding of SCS and expectations for pain relief, while consulting with physicians to support a multidisciplinary based patient selection. In addition, psychologists take part in preparing patients who were initially deemed unsuitable for SCS by providing recommendations and potential access to clinical care addressing psychological issues in chronic pain. Barriers to presurgical psychological assessments include limited access to skilled psychologists and issues with feasibility and appropriateness of standardized measures, and further work is needed to improve standardized methodology.

The Psychological Evaluation of Patients with Chronic Pain: a Review of BHI 2 Clinical and Forensic Interpretive Considerations

Pain is the most common reason why patients see a physician. Within the USA, it has been estimated that at least 116 million US adults suffer from chronic pain, with an estimated annual national economic cost of $560-635 billion. While pain is in part a sensory process, like sight, touch, or smell, pain is also in part an emotional experience, like depression, anxiety, or anger. Thus, chronic pain is arguably the quintessential biopsychosocial condition. Due to the overwhelming evidence of the biopsychosocial nature of pain and the value of psychological assessments, the majority of chronic pain guidelines recommend a psychological evaluation as an integral part of the diagnostic workup. One biopsychosocial inventory designed for the assessment of patients with chronic pain is the Battery for Health Improvement 2 (BHI 2). The BHI 2 is a standardized psychometric measure, with three validity measures, 16 clinical scales, and a multidimensional assessment of pain. This article will review how the BHI 2 was developed, BHI 2 concepts, validation research, and an overview of the description and interpretation of its scales. Like all measures, the BHI 2 has strengths and weaknesses of which the forensic psychologist should be aware, and particular purposes for which it is best suited. Guided by that knowledge, the BHI 2 can play a useful role in the forensic psychologist's toolbox.

Depressive burden is associated with a poorer surgical outcome among lumbar spinal stenosis patients: a 5-year follow-up study

BACKGROUND CONTEXT

In lumbar spinal stenosis (LSS), conservative treatment is usually the first choice of treatment. If conservative treatment fails, surgery is indicated. Psychological factors such as depression and anxiety are known to affect the outcome of surgery. Previous studies on depression and surgery outcome using long follow-up times are scarce.

PURPOSE

The purpose of this study was to investigate the effect of depressive symptoms on the surgical outcome during a 5-year follow-up among patients with LSS.

STUDY DESIGN

A prospective observational study.

PATIENT SAMPLE

Patient sample included 102 LSS patients who needed surgical treatment.

OUTCOME MEASURES

The outcome of surgery was evaluated with the Oswestry Disability Index (ODI), visual analog scale pain assessment, and self-reported walking capacity.

METHODS

The patients completed a set of questionnaires preoperatively and 3 and 6 months, as well as 1, 2, and 5 years after the surgery. Depressive symptoms were assessed with the Beck Depression Inventory. The depressive burden was estimated by summing all individual Beck Depression Inventory scores. Statistical analyses included cross-sectional group comparisons and linear regression analyses. No conflicts of interest.

RESULTS

On 5-year follow-up, a high depressive burden associated with a poorer outcome of surgery when assessed with the ODI. In linear regression analysis, a high depressive burden associated with higher ODI score.

CONCLUSIONS

Even slightly elevated long-term depressive symptoms in LSS patients are associated with an increased risk of a poorer functional ability after decompressive surgery.

The Nijmegen decision tool for chronic low back pain. Development of a clinical decision tool for secondary or tertiary spine care specialists

BACKGROUND

In Western Europe, low back pain has the greatest burden of all diseases. When back pain persists, different medical specialists are involved and a lack of consensus exists among these specialists for medical decision-making in Chronic Low Back Pain (CLBP).

OBJECTIVE

To develop a decision tool for secondary or tertiary spine care specialists to decide which patients with CLBP should be seen by a spine surgeon or by other non-surgical medical specialists.

METHODS

A Delphi study was performed to identify indicators predicting the outcome of interventions. In the preparatory stage evidence from international guidelines and literature were summarized. Eligible studies were reviews and longitudinal studies. Inclusion criteria: surgical or non-surgical interventions and persistence of complaints, CLBP-patients aged 18-65 years, reported baseline measures of predictive indicators, and one or more reported outcomes had to assess functional status, quality of life, pain intensity, employment status or a composite score. Subsequently, a three-round Delphi procedure, to reach consensus on candidate indicators, was performed among a multidisciplinary panel of 29 CLBP-professionals (>five years CLBP-experience). The pre-set threshold for general agreement was ≥70%. The final indicator set was used to develop a clinical decision tool.

RESULTS

A draft list with 53 candidate indicators (38 with conclusive evidence and 15 with inconclusive evidence) was included for the Delphi study. Consensus was reached to include 47 indicators. A first version of the decision tool was developed, consisting of a web-based screening questionnaire and a provisional decision algorithm.

CONCLUSIONS

This is the first clinical decision tool based on current scientific evidence and formal multidisciplinary consensus that helps referring the patient for consultation to a spine surgeon or a non-surgical spine care specialist. We expect that this tool considerably helps in clinical decision-making spine care, thereby improving efficient use of scarce sources and the outcomes of spinal interventions.

Percutaneous spinal cord stimulation for chronic pain: indications and patient selection

Percutaneous spinal cord stimulation has a clinical benefit in selected patients with chronic neuropathic pain related to failed back surgery syndrome and complex regional pain syndrome. Patients with other peripheral neuropathic pain syndromes may also respond favorably. The cause of the chronic pain must be established to rule out remediable causes. Drug abuse or aberrant drug-related behaviors should be assessed before proceeding. A psychological evaluation identifies patients who may not benefit. Risk factors for infection should be corrected where possible. This safe, reversible treatment should be considered early for patients with intractable peripheral neuropathic pain.

Spinal cord stimulation: Background and clinical application

Background Spinal cord stimulation (SCS) is a surgical treatment for chronic neuropathic pain refractory to conventional treatment. SCS treatment consists of one or more leads implanted in the epidural space of the spinal canal, connected to an implantable pulse generator (IPG). Each lead carries a number of contacts capable of delivering a weak electrical current to the spinal cord, evoking a feeling of peripheral paresthesia. With correct indication and if implanted by an experienced implanter, success rates generally are in the range of about 50-75%. Common indications include complex regional pain syndrome (CRPS I), angina pectoris, and radicular pain after failed back surgery syndrome, and the treatment is also used to treat stump pain after amputation, and pain due to peripheral nerve injury, peripheral vascular disease, and diabetic neuropathy. Recommended contraindications for the treatment include pregnancy, coagulopathy, severe addiction to psychoactive substances, and lack of ability to cooperate (e.g. due to active psychosis or cognitive impairment). Most common complications to the treatment include lead migration, lead breakage, infection, pain over the implant, and dural puncture. Despite extensive research in the area, the mechanisms of action are still only partially understood. Methods In this topical review the historical background behind the treatment is described and the current theories on the mechanism of action are presented. The implantation procedure is described in detail and illustrated with a series of intraoperative pictures. Finally, indications for SCS are discussed along with some of the controversies surrounding the therapy. Implications The reader is presented with a broad overview of spinal cord stimulation, including the historical and theoretical background, practical implantation technique, and clinical application.

Assessment and management of chronic pain in patients with depression and anxiety

This article will review the role of the pharmacist in the management of chronic pain in patients with comorbid mood disorders.

Surgical resilience: a review of resilience biomarkers and surgical recovery

BACKGROUND

Two distinct and large bodies of literature exist on resilience that are of potential interest for surgical outcomes. First is the literature on the impact of resilience on surgical recovery and wound-healing. Second is the literature on biomarkers for resilience, which largely focuses on neuropeptide Y (NPY), testosterone and dehydroepiandrosterone (DHEA). Despite this activity, there is a dearth of literature linking these two bodies of research by investigating biomarkers for surgical resilience and its impact on surgical recovery. This paper reviews both bodies of literature within the context of surgical recovery.

METHOD

Literature searches within Medline and Embase were conducted for studies and previous reviews of resilience biomarkers and for the impact of individual resilience on surgical recovery. Reference lists of the reviews were searched for additional papers. No systematic review is yet possible due to the novelty of the use of resilience biomarkers within a surgical context.

RESULTS

This is the first review to explore a potential link between resilience biomarkers and surgical recovery. There are a number of biomarkers that correlate with individual resilience levels and resilient individuals exhibit better recovery trajectories following surgery, suggesting a novel use of such biomarkers for the identification of "surgical resilience".

CONCLUSION

By identifying surgical resilience, there is potential for utilising these biomarkers as prognostic indicators of likely recovery trajectories from surgery, which in turn complement individualised peri-operative management.

Description and design considerations of a randomized clinical trial investigating the effect of a multidisciplinary cognitive-behavioural intervention for patients undergoing lumbar spinal fusion surgery

Background

The ideal rehabilitation strategy following lumbar spinal fusion surgery has not yet been established. This paper is a study protocol, describing the rationale behind and the details of a cognitive-behavioural rehabilitation intervention for lumbar spinal fusion patients based on the best available evidence. Predictors of poor outcome following spine surgery have been identified to provide targets for the intervention, and the components of the intervention were structured in accordance with the cognitive-behavioural model. The study aims to compare the clinical and economical effectiveness of a cognitive-behavioural rehabilitation strategy to that of usual care for patients undergoing lumbar spinal fusion surgery.

Methods/Design

The study is a randomized clinical trial including 96 patients scheduled for lumbar spinal fusion surgery due to degenerative disease or spondylolisthesis. Patients were recruited in the period October 2011 to July 2013, and the follow-up period is one year from date of surgery. Patients are allocated on a 1:2 ratio (control: intervention) to either treatment as usual (control group), which implies surgery and the standard postoperative rehabilitation, or in addition to this, a patient education focusing on pain behaviour and pain coping (intervention group). It takes place in a hospital setting, and consists of six group-based sessions, managed by a multidisciplinary team of health professionals.

The primary outcomes are disability (Oswestry Disability Index) and sick leave, while secondary outcomes include coping (Coping Strategies Questionnaire), fear-avoidance belief (Fear Avoidance Belief Questionnaire), pain (Low Back Pain Rating Scale, pain index), mobility during hospitalization (Cumulated Ambulation Score), generic health-related quality of life (EQ-5D) and resource use. Outcomes are measured using self report questionnaires, medical records and national registers.

Discussion

It is expected that the intervention can provide better functional outcome, less pain and earlier return to work after lumbar spinal fusion surgery. By combining knowledge and evidence from different knowledge areas, the project aims to provide new knowledge that can create greater consistency in patient treatment. We expect that the results can make a significant contribution to development of guidelines for good rehabilitation of patients undergoing lumbar spinal fusion.

Trial registration

Current Controlled Trials ISRCTN42281022.

Back pain in patients with degenerative spine disease and intradural spinal tumor: what to treat? when to treat?

BACKGROUND

Back pain is common in industrialized countries and one of the most frequent causes of work incapacity. Successful treatment is, therefore, not only important for improving the symptoms and the quality of life of these patients but also for socioeconomic reasons. Back pain is frequently caused by degenerative spine disease. Intradural spinal tumors are rare with an annual incidence of 2-4/1,00,000 and are mostly associated with neurological deficits and radicular and nocturnal pain. Back pain is not commonly described as a concomitant symptom, such that in patients with both a tumor and degenerative spine disease, any back pain is typically attributed to the degeneration rather than the tumor.

OBJECTIVE

The aim of the present retrospective investigation was to study and analyze the impact of microsurgery on back/neck pain in patients with intradural spinal tumor in the presence of degenerative spinal disease in adjacent spinal segments.

METHODS

Fifty-eight consecutive patients underwent microsurgical, intradural tumor surgery using a standardized protocol assisted by multimodal intraoperative neuromonitoring. Clinical symptoms, complications and surgery characteristics were documented. Standardized questionnaires were used to measure outcome from the surgeon's and the patient's perspectives (Spine Tango Registry and Core Outcome Measures Index). Follow-up included clinical and neuroradiological examinations 6 weeks, 3 months and 1 year postoperatively.

RESULTS

Back/neck pain as a leading symptom and coexisting degenerative spine disease was present in 27/58 (47 %) of the tumor patients, and these comprised to group under study. Patients underwent tumor surgery only, without addressing the degenerative spinal disease. Remission rate after tumor removal was 85 %. There were no major surgical complications. Back/neck pain as the leading symptom was eradicated in 67 % of patients. There were 7 % of patients who required further invasive therapy for their degenerative spinal disease.

CONCLUSIONS

Intradural spinal tumor surgery improves back/neck pain in patients with coexisting severe degenerative spinal disease. Intradural spinal tumors seem to be the only cause of back/neck pain more often than appreciated. In these patients suffering from both pathologies, there is a higher risk of surgical overtreatment than undertreatment. Therefore, elaborate clinical and radiological examinations should be performed preoperatively and the indication for stabilization/fusion should be discussed carefully in patients foreseen for first time intradural tumor surgery.

Factors associated with the success of trial spinal cord stimulation in patients with chronic pain from failed back surgery syndrome

OBJECTIVE

Spinal cord stimulation (SCS) is an effective means of treatment of chronic neuropathic pain from failed back surgery syndrome (FBSS). Because the success of trial stimulation is an essential part of SCS, we investigated factors associated with success of trial stimulation.

METHODS

Successful trial stimulation was possible in 26 of 44 patients (63.6%) who underwent insertion of electrodes for the treatment of chronic pain from FBSS. To investigate factors associated with successful trial stimulation, patients were classified into two groups (success and failure in trial). We investigated the following factors : age, sex, predominant pain areas (axial, limb, axial combined with limbs), number of operations, duration of preoperative pain, type of electrode (cylindrical/paddle), predominant type of pain (nociceptive, neuropathic, mixed), degree of sensory loss in painful areas, presence of motor weakness, and preoperative Visual Analogue Scale.

RESULTS

There were no significant differences between the two groups in terms of age, degree of pain, number of operations, and duration of pain (p>0.05). Univariate analysis revealed that the type of electrode and presence of severe sensory deficits were significantly associated with the success of trial stimulation (p<0.05). However, the remaining variable, sex, type of pain, main location of pain, degree of pain duration, degree of sensory loss, and presence of motor weakness, were not associated with the trial success of SCS for FBSS.

CONCLUSION

Trial stimulation with paddle leads was more successful. If severe sensory deficits occur in the painful dermatomes in FBSS, trial stimulation were less effective.

Do preoperative fear avoidance model factors predict outcomes after lumbar disc herniation surgery? A systematic review

BACKGROUND

Lumbar disc herniation (LDH) surgery is usually recommended when conservative treatments fail to manage patients' symptoms. However, many patients undergoing LDH surgery continue to report pain and disability. Preoperative psychological factors have shown to be predictive for postoperative outcomes. Our aim was to systematically review studies that prospectively examined the prognostic value of factors in the Fear Avoidance Model (FAM), including back pain, leg pain, catastrophizing, anxiety, fear-avoidance, depression, physical activity and disability, to predict postoperative outcomes in patients undergoing LDH surgery.

METHODS

We performed a systematic literature review of prospective studies that measured any FAM factors preoperatively to predict postoperative outcomes for patients undergoing LDH surgery. Our search databases included PubMed, CINAHL, and PsycINFO. We assessed the quality of each included study using a certain quality assessment list. Degree of agreement between reviewers on quality assessment was examined. Results related to FAM factors in the included studies were summarized.

RESULTS

Thirteen prospective studies met our inclusion criteria. Most studies were considered high quality. Heterogeneity was present between the included studies in many aspects. The most common FAM factors examinered were baseline pain, disability and depression. In, general, depression, fear-avoidance behaviors, passive pain coping, and anxiety FAM factors appeared to have negative influence on LDH surgical outcome. Baseline back pain and leg pain appeared to have differing prognostic value on LDH surgical outcomes.

CONCLUSIONS

FAM factors seem to influence LDH surgical outcomes. Patients with high levels of depression, anxiety and fear-avoidance behaviors are more likely to have poor outcomes following LDH surgery. Conversely, high levels of leg pain, but not back pain seem to be predictor for favorable LDH surgery outcome. More research is needed to determine the exact role of FAM factors on LDH surgical outcome and the value for screening for these factors.

Psychological screening/phenotyping as predictors for spinal cord stimulation

Spinal cord stimulation (SCS) is becoming a widely used treatment for a number of pain conditions and is frequently considered as a pain management option when conservative or less invasive techniques have proven to be ineffective. Potential indications for SCS include complex regional pain syndrome (CRPS), postherpetic neuralgia, traumatic nerve injury, failed back surgery syndrome, refractory angina pectoris, peripheral vascular disease, neuropathic pain, and visceral pain (Guttman et al. Pain Pract. 9:308-11, 2009). While research on SCS is in its infancy, it is clear that substantial variation exists in the degree of benefit obtained from SCS, and the procedure does not come without risks; thus focused patient selection is becoming very important. Psychological characteristics play an important role in shaping individual differences in the pain experience and may influence responses to SCS, as well as a variety of other pain treatments (Doleys Neurosurg Focus 21:E1, 2006). In addition to psychological assessment, quantitative sensory testing (QST) procedures offer another valuable resource in forecasting who may benefit most from SCS and may also shed light on mechanisms underlying the individual characteristics promoting the effectiveness of such procedures (Eisenberg et al. Pain Pract. 6:161-165, 2006). Here, we present a brief overview of recent studies examining these factors in their relationship with SCS outcomes.

A six year retrospective review of occipital nerve stimulation practice--controversies and challenges of an emerging technique for treating refractory headache syndromes

Background

A retrospective review of patients treated with Occipital Nerve Stimulation (ONS) at two large tertiary referral centres has been audited in order to optimise future treatment pathways.

Methods

Patient’s medical records were retrospectively reviewed, and each patient was contacted by a trained headache expert to confirm clinical diagnosis and system efficacy. Results were compared to reported outcomes in current literature on ONS for primary headaches.

Results

Twenty-five patients underwent a trial of ONS between January 2007 and December 2012, and 23 patients went on to have permanent implantation of ONS. All 23 patients reached one-year follow/up, and 14 of them (61%) exceeded two years of follow-up. Seventeen of the 23 had refractory chronic migraine (rCM), and 3 refractory occipital neuralgia (ON). 11 of the 19 rCM patients had been referred with an incorrect headache diagnosis. Nine of the rCM patients (53%) reported 50% or more reduction in headache pain intensity and or frequency at long term follow-up (11–77 months). All 3 ON patients reported more than 50% reduction in pain intensity and/or frequency at 28–31 months. Ten (43%) subjects underwent surgical revision after an average of 11 ± 7 months from permanent implantation - in 90% of cases due to lead problems. Seven patients attended a specifically designed, multi-disciplinary, two-week pre-implant programme and showed improved scores across all measured psychological and functional parameters independent of response to subsequent ONS.

Conclusions

Our retrospective review: 1) confirms the long-term ONS success rate in refractory chronic headaches, consistent with previously published studies; 2) suggests that some headaches types may respond better to ONS than others (ON vs CM); 3) calls into question the role of trial stimulation in ONS; 4) confirms the high rate of complications related to the equipment not originally designed for ONS; 5) emphasises the need for specialist multidisciplinary care in these patients.

Psychopathological influence of lumbar disc herniation in male adolescent

PURPOSE

There is no report about psychopathological effect causing by disc herniation. The disease could impose psychopathological influence on the social life, the treatment period, and response to the treatment. This study was to evaluate retrospectively the psychopathological influence of lumbar disc herniation (LDH) among Korean 19-year-old males.

MATERIALS AND METHODS

We compared the Korean military multiphasic personality inventory (KMPI) profiles of 74 LDH cases with the KMPI profiles of 150 controls. The LDH groups were categorized to 2 groups according to the presence of thecal sac compression by disc materials, and evaluated the relation between the KMPI and LDH.

RESULTS

The decrease of the faking-good response scale and increase of the faking-bad response scale were observed more in the LDH group than in the normal volunteer group (p<0.05). The neurosis set such as anxiety, depression and somatization was markedly increased in the LDH group compared to the normal volunteers group (p<0.05). The scale of personality disorder was also increased more in the LDH group (p=0.002). The differences of KMPI scales were not correlated with the severe pathology of LDH.

CONCLUSION

Young male with LDH may tend to have more abnormal results of multiphasic personality inventory test compared to the normal volunteers, suggesting that LDH may be related to the psychopathology in young males in Korea. Therefore, clinicians are recommended to evaluate and treat the psychopathological aspects in patients with LDH.

Negative beliefs and psychological disturbance in spine surgery patients: a cause or consequence of a poor treatment outcome?

PURPOSE

Chronic musculoskeletal pain is often associated with psychological distress and maladaptive beliefs and these are sometimes reported to have a negative impact on surgical outcome. The influence of a surgical intervention, and in particular its outcome, on the course of change in psychological status is poorly documented. In this prospective study, we sought to examine the dynamic interplay between psychological factors and outcome in patients undergoing decompression surgery for spinal stenosis/herniated disc.

METHODS

Before and 12 months after surgery, 159 patients (100 men, 59 women; 65 ± 11 years) completed a questionnaire booklet containing questions on socio-demographics, medical history, pain characteristics (intensity, frequency, use of medication), psychological disturbance [ZUNG Depression Scale and Modified Somatic Perception Questionnaire (MSPQ)], catastrophising (sub-scale of the Coping Strategies Questionnaire) and disability (Roland and Morris questionnaire) and the Fear Avoidance Beliefs Questionnaire about physical activity (FABQ-PA). The global outcome of surgery was assessed at 12 months using a five-point Likert scale and dichotomised as "good" (operation helped/helped a lot; coded 1) and "poor" (operation helped only little/did not help/made things worse; coded 0).

RESULTS

Valid questionnaire data were available for 148 patients at 12 months' follow-up: 113 (76.4 %) reported a good outcome and 35 (23.6 %) a poor outcome. In univariate analyses, the following baseline variables each significantly (p < 0.05) predicted a good 12-month global outcome: no involvement in a disability claim, and lower LBP frequency, average LBP in the last week, average score on all pain scales, FABQ-PA and catastrophising. In multiple logistic regression, only lower FABQ-PA scores [OR 0.877 (95 %CI 0.809-0.949), p = 0.001] and lower LBP frequency at baseline [OR 0.340 (1.249-1.783), p < 0.0001] significantly predicted a good outcome at 12 months. A second "explanatory" logistic regression model revealed that a good outcome at 12 months was significantly associated with improvements (from baseline to 12 months) in average score on all the pain intensity scales [OR 1.6879 (1.187-2.398)], general health [OR 1.246 (1.004-1.545)], psychological disturbance [OR 1.073 (1.006-1.144)] and Roland Morris Disability [OR 1.243 (1.074-1.439)].

CONCLUSION

In a multivariable prospective (predictive) model, FABQ-PA was the only baseline psychological factor that significantly predicted outcome. Future studies should assess whether pre-operative cognitive-behavioural therapy in patients with maladaptive beliefs improves treatment outcome. Psychological disturbance did not significantly predict outcome, but it improved post-operatively in patients with a good outcome and worsened in those with a poor outcome. Rather than being a risk factor for poor outcome, in this group it appeared to be more a consequence of long-standing, unremitting pain that improved when symptoms resolved after successful surgery.

Early predictors of lumbar spine surgery after occupational back injury: results from a prospective study of workers in Washington State

STUDY DESIGN

Prospective population-based cohort study.

OBJECTIVE

To identify early predictors of lumbar spine surgery within 3 years after occupational back injury.

SUMMARY OF BACKGROUND DATA

Back injuries are the most prevalent occupational injury in the United States. Few prospective studies have examined early predictors of spine surgery after work-related back injury.

METHODS

Using Disability Risk Identification Study Cohort (D-RISC) data, we examined the early predictors of lumbar spine surgery within 3 years among Washington State workers, with new workers compensation temporary total disability claims for back injuries. Baseline measures included worker-reported measures obtained approximately 3 weeks after claim submission. We used medical bill data to determine whether participants underwent surgery, covered by the claim, within 3 years. Baseline predictors (P < 0.10) of surgery in bivariate analyses were included in a multivariate logistic regression model predicting lumbar spine surgery. The area under the receiver operating characteristic curve of the model was used to determine the model's ability to identify correctly workers who underwent surgery.

RESULTS

In the D-RISC sample of 1885 workers, 174 (9.2%) had a lumbar spine surgery within 3 years. Baseline variables associated with surgery (P < 0.05) in the multivariate model included higher Roland-Morris Disability Questionnaire scores, greater injury severity, and surgeon as first provider seen for the injury. Reduced odds of surgery were observed for those younger than 35 years, females, Hispanics, and those whose first provider was a chiropractor. Approximately 42.7% of workers who first saw a surgeon had surgery, in contrast to only 1.5% of those who saw a chiropractor. The area under the receiver operating characteristic curve of the multivariate model was 0.93 (95% confidence interval, 0.92-0.95), indicating excellent ability to discriminate between workers who would versus would not have surgery.

CONCLUSION

Baseline variables in multiple domains predicted lumbar spine surgery. There was a very strong association between surgery and first provider seen for the injury even after adjustment for other important variables.

Surgically induced neuropathic pain: understanding the perioperative process

Nerve damage takes place during surgery. As a consequence, significant numbers (10%-40%) of patients experience chronic neuropathic pain termed surgically induced neuropathic pain (SNPP). The initiating surgery and nerve damage set off a cascade of events that includes both pain and an inflammatory response, resulting in "peripheral and central sensitization," with the latter resulting from repeated barrages of neural activity from nociceptors. In affected patients, these initial events produce chemical, structural, and functional changes in the peripheral and central nervous systems (CNS). The maladaptive changes in damaged nerves lead to peripheral manifestations of the neuropathic state-allodynia, sensory loss, shooting pains, etc, that can manifest long after the effects of the surgical injury have resolved. The CNS manifestations that occur are termed "centralization of pain" and affect sensory, emotional, and other (eg, cognitive) systems as well as contributing to some of the manifestations of the chronic pain syndrome (eg, depression). Currently there are no objective measures of nociception and pain in the perioperative period. As such, intermittent or continuous pain may take place during and after surgery. New technologies including direct measures of specific brain function of nociception and new insights into preoperative evaluation of patients including genetic predisposition, appear to provide initial opportunities for decreasing the burden of SNPP, until treatments with high efficacy and low adverse effects that either prevent or treat pain are discovered.

Overview of data-synthesis in systematic reviews of studies on outcome prediction models

Background

Many prognostic models have been developed. Different types of models, i.e. prognostic factor and outcome prediction studies, serve different purposes, which should be reflected in how the results are summarized in reviews. Therefore we set out to investigate how authors of reviews synthesize and report the results of primary outcome prediction studies.

Methods

Outcome prediction reviews published in MEDLINE between October 2005 and March 2011 were eligible and 127 Systematic reviews with the aim to summarize outcome prediction studies written in English were identified for inclusion.

Characteristics of the reviews and the primary studies that were included were independently assessed by 2 review authors, using standardized forms.

Results

After consensus meetings a total of 50 systematic reviews that met the inclusion criteria were included. The type of primary studies included (prognostic factor or outcome prediction) was unclear in two-thirds of the reviews. A minority of the reviews reported univariable or multivariable point estimates and measures of dispersion from the primary studies. Moreover, the variables considered for outcome prediction model development were often not reported, or were unclear. In most reviews there was no information about model performance. Quantitative analysis was performed in 10 reviews, and 49 reviews assessed the primary studies qualitatively. In both analyses types a range of different methods was used to present the results of the outcome prediction studies.

Conclusions

Different methods are applied to synthesize primary study results but quantitative analysis is rarely performed. The description of its objectives and of the primary studies is suboptimal and performance parameters of the outcome prediction models are rarely mentioned. The poor reporting and the wide variety of data synthesis strategies are prone to influence the conclusions of outcome prediction reviews. Therefore, there is much room for improvement in reviews of outcome prediction studies.

Utilisation of search filters in systematic reviews of prognosis questions

BACKGROUND

Search filters are designed to increase efficiency of information retrieval and can be particularly useful in limiting the large numbers of articles retrieved for systematic reviews (SRs). Existing published prognosis search filters (or hedges) have lower sensitivity and precision values than their therapy counterparts.

OBJECTIVES

Taking into account the relatively poor performance of prognosis filters, this study seeks to identify which methods of limiting search results to prognostic studies are most often used by SR teams.

METHODS

One hundred and three SRs of prognostic studies published in 2009 and indexed in MEDLINE were retrieved. Each review's search strategy was reviewed and prognosis-related search terms were extracted.

RESULTS

Forty-seven of 103 studies used prognosis-related terms to limit the search. Six SRs of 103 did not specify their search terms, and the remaining 50 SRs used content terms only (no terms related to methodology or prognosis). Of the 47 strategies using prognosis-related terms, only six used a published filter. Many SRs used few or poorly selected prognosis-related search terms which are unlikely to provide the sensitivity generally sought for SRs.

CONCLUSIONS

Published prognosis search filters are used in only a small minority of prognosis SRs.

eHealth program to empower patients in returning to normal activities and work after gynecological surgery: intervention mapping as a useful method for development

BACKGROUND

Full recovery after gynecological surgery takes much longer than expected regardless of surgical technique or the level of invasiveness. After discharge, detailed convalescence recommendations are not provided to patients typically, and postoperative care is fragmented, poorly coordinated, and given only on demand. For patients, this contributes to irrational beliefs and avoidance of resumption of activities and can result in a prolonged sick leave.

OBJECTIVE

To develop an eHealth intervention that empowers gynecological patients during the perioperative period to obtain timely return to work (RTW) and prevent work disability.

METHODS

The intervention mapping (IM) protocol was used to develop the eHealth intervention. A literature search about behavioral and environmental conditions of prolonged sick leave and delayed RTW in patients was performed. Patients' needs, attitudes, and beliefs regarding postoperative recovery and resumption of work were identified through focus group discussions. Additionally, a literature search was performed to obtain determinants, methods, and strategies for the development of a suitable interactive eHealth intervention to empower patients to return to normal activities after gynecological surgery, including work. Finally, the eHealth intervention was evaluated by focus group participants, medical doctors, and eHealth specialists through questionnaires.

RESULTS

Twenty-one patients participated in the focus group discussions. Sufficient, uniform, and tailored information regarding surgical procedures, complications, and resumption of activities and work were considered most essential. Knowing who to contact in case of mental or physical complaints, and counseling and tools for work reintegration were also considered important. Finally, opportunities to exchange experiences with other patients were a major issue. Considering the determinants of the Attitude-Social influence-self-Efficacy (ASE) model, various strategies based on a combination of theory and evidence were used, resulting in an eHealth intervention with different interactive functionalities including tailored convalescence recommendations and a video to communicate the most common pitfalls during the perioperative period to patients and employers. Fifteen patients in the focus groups, 11 physicians, and 3 eHealth specialists suggested points for improvement to optimize the usability of the eHealth intervention and judged it an approachable, appropriate, and attractive eHealth intervention to empower gynecological patients.

CONCLUSIONS

The IM protocol was a useful method to develop an eHealth intervention based on both theory and evidence. All patients and stakeholders judged the eHealth intervention to be a promising tool to empower gynecological patients during the perioperative period and to help them to return to normal activities and work.

Psychological risk factors for poor outcome of spine surgery and spinal cord stimulator implant: a review of the literature and their assessment with the MMPI-2-RF

Back pain is experienced by up to of 85% of the United States population. Most often it resolves with minimal to no medical treatment. For those whose pain endures, worsens, or becomes protracted, conservative care is typically first attempted. Individuals who continue to experience significant back pain are often considered for surgical procedures, the results of which are not uniformly positive. The consequences of failed surgical intervention can be quite devastating, and psychosocial factors have been found to predict poor outcome. The literature on psychosocial risk factors for failed back surgery is reviewed first, identifying psychological dysfunction in the domains of emotions, cognitions, behavior, and interpersonal processes as increasing the risk for failed back surgery. Empirical findings with the MMPI-2 Restructured Form (MMPI-2-RF) are presented next, including descriptive analyses with a sample of 1341 individuals assessed as part of a pre-surgical psychological screening. Correlations between MMPI-2-RF scale scores and measures of the primary risk factors identified in this review are reported for a smaller sample of 197 pre-surgical candidates. Interpretive implications of the MMPI-2-RF findings are discussed along with suggestions for further research in this area.

Risk factor assessment for problematic use of opioids for chronic pain

Opioid analgesics provide effective treatment for noncancer pain, but many health providers have concerns about cognitive effects, tolerance, dependence, and addiction. Misuse of opioids is prominent in patients with chronic pain and early recognition of misuse risk could help providers offer adequate patient care while implementing appropriate levels of monitoring to reduce aberrant drug-related behaviors. Many persons with chronic pain also have significant medical and psychiatric comorbidities that affect treatment decisions. Neuropsychologists can play an important role in the identification of psychological and social dysfunction and in matching personal characteristics to effective interventions as part of a multidisciplinary approach to pain management. The assessment of different domains using semi-structured interviews, sensory and neuropsychological testing, and standardized self-report measures permits identification of somatosensory, emotional, cognitive, behavioral, and social issues in order to facilitate treatment planning. In this review we discuss opioid abuse and misuse issues that often arise in the treatment of patients with chronic pain, and present an overview of assessment and treatment strategies that can be effective in improving outcomes associated with the use of prescription opioids for pain. Finally we briefly discuss the effect of opiate analgesics on cognition and review some intervention strategies for chronic pain patients.

Relationship between STarT Back Screening Tool and prognosis for low back pain patients receiving spinal manipulative therapy

Background

Low back pain (LBP) is common and costly and few treatments have been shown to be markedly superior to any other. Effort has been focused on stratifying patients to better target treatment. Recently the STarT Back Screening Tool (SBT) has been developed for use in primary care to enable sub grouping of patients based on modifiable baseline characteristics and has been shown to be associated with differential outcomes. In the UK the SBT is being recommended to assist in care decisions for those presenting to general practitioners with LBP. In the light of growing recommendation for widespread use of this tool, generalisability to other LBP populations is important. However, studies to date have focused only on patients attending physiotherapy whereas LBP patients seeking other treatment have not been investigated.

Aims

This study aims to investigate the utility of the SBT to predict outcomes in LBP patients presenting for chiropractic management.

Methods

A total of 404 patients undergoing chiropractic care were asked to complete the SBT before initial treatment. Clinical outcomes were collected at 14, 30 and 90 days following this initial consultation. The clinical course was described comparing SBT categories and logistic regression analysis performed to examine the tool’s prognostic utility.

Results

Although the high-risk categories had greater pain at baseline this difference rapidly faded, with both change in composite outcome scores and pain scores being statistically insignificant between the risk groups at 30 and 90 days follow up. In addition, both univariate and adjusted analysis showed no prognostic utility of the SBT categorisations to differentiate clinical outcomes between risk groups.

Conclusion

Whilst the SBT appears useful in some back pain populations it does not appear to differentiate outcomes in LBP patients seeking chiropractic care.

Relationship of negative affect and outcome of an opioid therapy trial among low back pain patients

OBJECTIVES

Patients with chronic noncancer pain frequently report symptoms of depression and anxiety (negative affect), which are associated with higher ratings of pain intensity and a greater likelihood of being prescribed chronic opioid therapy. The purpose of this secondary analysis was to test the hypothesis that initial levels of negative affect can predict treatment-related outcomes in a double-blind, placebo-controlled study of extended-release (ER) hydromorphone among opioid-tolerant patients with chronic low back pain.

METHODS

Four hundred fifty-nine (N = 459) patients participated in the titration/conversion phase of a multicenter study, of which 268 were randomized to receive once-daily hydromorphone or placebo. All patients completed the Hospital Anxiety and Depression Scale (HADS) at baseline and were divided evenly into Low (N = 157), Moderate (N = 155), and High (N = 147) negative affect groups based on their scores. Group differences in numerical pain intensity measures at home and in the clinic, Roland-Morris Disability ratings, and measures of symptoms from the Subjective Opiate Withdrawal Scale (SOWS) throughout the trial were analyzed.

RESULTS

Two hundred sixty-eight of the initial 459 subjects who entered the 2 to 4-week titration/conversion phase (pretreatment) were successfully randomized to either placebo or ER hydromorphone; a total of 110 patients then completed this double-blind phase of the study. Those in the Moderate and High negative affect groups tended to drop out more often during the titration/conversion phase because of the adverse effects or lack of efficacy of their prescribed opioid than those in the Low negative mood group (P < 0.05). Overall, those patients in the Moderate and High groups reported significantly higher pain intensity scores in at-home and in-clinic pain intensity ratings (P < 0.05), greater disability on the Roland-Morris Scale (P < 0.01), and more withdrawal symptoms on the SOWS (P < 0.05) than those in the Low group. Higher negative affect scores also predicted less favorable ratings of the study drug during the titration phase (P < 0.05). Interestingly, the High negative affect group showed the most improvement in pain in the placebo condition (P < 0.05).

CONCLUSIONS

Negative affect is associated with diminished benefit during a trial of opioid therapy and is predictive of dropout in a controlled clinical trial.

Interventional pain medicine: retreat from the biopsychosocial model of pain

The field of pain medicine has shifted from multidisciplinary rehabilitation to procedure-focused interventional pain medicine (IPM). Considerable controversy exists regarding the efficacy of IPM and its more narrow focus on nociception as an exclusive target of pain treatment. This topical review aims to examine pain research and treatment outcome studies that support a biopsychosocial model of pain, and to critique the clinical practice of IPM given its departure from the premises of a biopsychosocial model. A modern definition of pain and findings from clinical and basic science studies indicate that pain-related psychological factors are integral to pain perception. The clinical viability of IPM is challenged based upon its biomedical view of peripheral nociception as a primary source of pain and the potential of this viewpoint to foster maladaptive pain attributions and discourage the use of pain coping strategies among chronic pain patients. IPM should adopt a biopsychosocial perspective on pain and operate within a framework of multidisciplinary pain rehabilitation to improve its effectiveness.

Muscarinic pain pharmacology: realizing the promise of novel analgesics by overcoming old challenges

The antinociceptive and analgesic effects of muscarinic receptor ligands in human and nonhuman species have been evident for more than half a century. In this review, we describe the current understanding of the roles of different muscarinic subtypes in pain modulation and their mechanism of action along the pain signaling pathway, including peripheral nociception, spinal cord pain processing, and supraspinal analgesia. Extensive preclinical and clinical validation of these mechanisms points to the development of selective muscarinic agonists as one of the most exciting and promising avenues toward novel pain medications.

Factor structure and concurrent/convergent validity of the modified somatic perception questionnaire and pain beliefs instrument

OBJECTIVE

Our goal was to create a parsimonious combination of the Modified Somatic Perception Questionnaire (MSPQ) and the Pain Beliefs Screening Instrument (PBSI) through factorial structural analysis and to investigate the associations of the new scale (if unique) to disability, health condition, and quality of life report in patients with neck and low back pain scheduled for spine fusion surgery.

METHODS

Factor analysis was used to refine all items within the 2 scales to 4 distinct factors: (1) somatic complaints of the head/neck, (2) somatic complaints of the gastrointestinal symptom, (3) pain beliefs and fear, and (4) self perception of serious problems. Each factor was assessed for concurrent validity with other well-established tools including the Deyo comorbidity index, the Short Form (SF)-36 mental and physical component subscales, and the Oswestry and Neck Disability Indices (ODI/NDI).

RESULTS

The PBSI was fairly to moderately correlated with assessment tools of quality of life (SF-36) and disability assessment (ODI/NDI). Some of the items in the factor 1 from the MSPQ were slightly associated with the Deyo comorbidity index but not with the ODI/NDI.

CONCLUSIONS

The items from the MSPQ failed to associate with measures of quality of life and disability and thus may provide only marginal value when assessing the multidimensional aspects associated with neck and low back pain. The PBSI has moderate correlation with disability assessments. Neither tool was found to strongly correlate with disability measures or with SF-36 scales (mental and physical component subscales). Additional tools may be needed to further identify the dimensions associated with chronic pain patients.

[Selected interventional methods for the treatment of chronic pain : part 2: regional anesthetic techniques close to the spinal cord and neuromodulative methods]

Approximately 5-8 million people in Germany suffer from chronic pain and some patients can profit from specific interventional techniques. In detail these are regional anesthetic techniques close to the spinal cord, neuromodulation, blocks of the sympathetic chain and peripheral nerve blocks. Part 2 of the article presents regional anesthetic techniques close to the spinal cord and neuromodulative methods. Regional anesthetic techniques close to the spinal cord are of high importance for the treatment of chronic low back pain although the efficiency is highly disputed due to the lack of evidence. Neuromodulation includes amongst others intrathecal pharmacotherapy and spinal cord stimulation, which are used for highly selected patients and can lead to very good results for these patients.

Systematic review of prevalence, correlates, and treatment outcomes for chronic non-cancer pain in patients with comorbid substance use disorder

Recent data suggest that comorbid substance use disorders (SUDs) are common among chronic non-cancer pain (CNCP) patients; however, prevalence rates vary across studies and findings are limited regarding treatment options for CNCP patients with comorbid SUD. The purpose of this systematic review is to assess the prevalence, associated demographic and clinical characteristics, and treatment outcomes for CNCP patients with comorbid SUD. We conducted searches from Ovid MEDLINE, PsychINFO, and PubMED from 1950 through February 2010 and retrieved the references. Thirty-eight studies met inclusion criteria and provided data that addressed our key questions. Three to forty-eight percent of CNCP patients have a current SUD. There are no demographic or clinical factors that consistently differentiate CNCP patients with comorbid SUD from patients without SUD, though SUD patients appear to be at greater risk for aberrant medication-related behaviors. CNCP patients with SUD are more likely to be prescribed opioid medications and at higher doses than CNCP patients without a history of SUD. CNCP patients with comorbid SUD do not significantly differ in their responses to treatment compared to CNCP patients without SUD, though the quality of this evidence is low. Limited data are available to identify predictors of treatment outcome. Although clinical experience and research suggests that SUDs are common among CNCP patients, only limited data are available to guide clinicians who treat this population. Research is needed to increase understanding of the prevalence, correlates, and responses to treatment of CNCP patients with comorbid SUDs.

Understanding and managing patients with chronic pain

The specialty of oral and maxillofacial surgery has had at its core the foundations of anesthesia and pain and anxiety control. This article attempts to refamiliarize the reader with clinical pearls helpful in the management of patients with chronic pain conditions. The authors also hope to highlight the interplay of chronic pain and psychology as it relates to the oral and maxillofacial surgery patient. To that end, the article outlines and reviews the neurophysiology of pain, the definitions of pain, conditions encountered by the oral and maxillofacial surgeon that produce chronic pain, the psychological impact and comorbidities associated with patients experiencing chronic pain conditions, and concepts of multimodal treatment for patients experiencing chronic pain conditions.

[Predictive factors and prevention of chronic postoperative pelvic and perineal pain]

INTRODUCTION

Chronic postoperative pain has been defined as pain arising after a surgical operation, present for at least 2 months, with no organic (active cancer or chronic infection) or preexisting cause. The purpose of this article is to review the risk factors and prevention of chronic postoperative pelvic and perineal pain.

MATERIAL AND METHODS

A review of the literature was performed by searching PubMed for articles on risk factors and prevention of chronic postoperative pelvic and perineal pain.

RESULTS

Chronic postoperative pain is frequent, disabling and represent a high cost to the community. This pain is generated by variable and complex interactions between the surgical procedure (the operated zone, perioperative management, the disease requiring the operative procedure) and the patient (age, gender, genetics, concomitant diseases, personal history). The multifactorial nature of chronic postoperative pain suggests the need for multidisciplinary management with prevention and reduction of the main risk factors. Similarly, appropriate management of acute postoperative pain has a major impact on the risk of chronic pain.

CONCLUSION

A good knowledge of the risk factors and appropriate prevention can decrease the incidence and consequences of chronic postoperative pain.

Implantation of an intercostal nerve stimulator for chronic abdominal pain

Chronic abdominal pain is not uncommon and can be difficult to manage. We present the case of a 17-year-old man with a 4-year history of chronic abdominal pain. The patient had previously undergone abdominal surgery by way of laparoscopic appendicectomy and right nephrectomy for a mal-rotated kidney. The patient continued to suffer right-sided abdominal pain which was not controlled by analgesia. We report the successful implantation of a right D11 intercostal nerve stimulator to control the patient's pain. This is the first report of an implantable intercostal nerve stimulator to control intractable chronic abdominal pain.