A Systematic Review of Assessments and Interventions for Chronic Pain in Young Children With or at High Risk for Cerebral Palsy

BACKGROUND

Pain is common in children with cerebral palsy. The purpose of this systematic review was to evaluate the evidence regarding assessments and interventions for chronic pain in children aged ≤2 years with or at high risk for cerebral palsy.

METHODS

A comprehensive literature search was performed. Included articles were screened using PRISMA guidelines and quality of evidence was reviewed using best-evidence tools by independent reviewers. Using social media channels, an online survey was conducted to elicit parent preferences.

RESULTS

Six articles met criteria. Parent perception was an assessment option. Three pharmacologic interventions (gabapentin, medical cannabis, botulinum toxin type A) and 1 nonpharmacologic intervention were identified. Parent survey report parent-comfort and other nonpharmacologic interventions ranked as most preferable.

CONCLUSION

A conditional GRADE recommendation was in favor of parent report for pain assessment. Clinical trials are sorely needed because of the lack of evidence for safety and efficacy of pharmacologic interventions.

Procedure-specific acute pain trajectory after elective total hip arthroplasty: systematic review and data synthesis

BACKGROUND

For most procedures, there is insufficient evidence to guide clinicians in the optimal timing of advanced analgesic methods, which should be based on the expected time course of acute postoperative pain severity and aimed at time points where basic analgesia has proven insufficient.

METHODS

We conducted a systematic search of the literature of analgesic trials for total hip arthroplasty (THA), extracting and pooling pain scores across studies, weighted for study size. Patients were grouped according to basic anaesthetic method used (general, spinal), and adjuvant analgesic interventions such as nerve blocks, local infiltration analgesia, and multimodal analgesia. Special consideration was given to high-risk populations such as chronic pain or opioid-dependent patients.

RESULTS

We identified and analysed 71 trials with 5973 patients and constructed pain trajectories from the available pain scores. In most patients undergoing THA under general anaesthesia on a basic analgesic regimen, postoperative acute pain recedes to a mild level (<4/10) by 4 h after surgery. We note substantial variability in pain intensity even in patients subjected to similar analgesic regimens. Chronic pain or opioid-dependent patients were most often actively excluded from studies, and never analysed separately.

CONCLUSIONS

We have demonstrated that it is feasible to construct procedure-specific pain curves to guide clinicians on the timing of advanced analgesic measures. Acute intense postoperative pain after THA should have resolved by 4-6 h after surgery in most patients. However, there is a substantial gap in knowledge on the management of patients with chronic pain and opioid-dependent patients.

Contemporary Analysis of Minimal Clinically Important Difference in the Neurosurgical Literature

BACKGROUND

Minimal clinically important difference (MCID) is determined when a patient or physician defines the minimal change that outweighs the costs and untoward effects of a treatment. These measurements are "anchored" to validated quality-of-life instruments or physician-rated, disease-activity indices. To capture the subjective clinical experience in a measurable way, there is an increasing use of MCID.

OBJECTIVE

To review the overall concept, method of calculation, strengths, and weaknesses of MCID and its application in the neurosurgical literature.

METHODS

Recent articles were reviewed based on PubMed query. To illustrate the strengths and limitations of MCID, studies regarding the measurement of pain are emphasized and their impact on subsequent publications queried.

RESULTS

MCID varies by population baseline characteristics and calculation method. In the context of pain, MCID varied based on the quality of pain, chronicity, and treatment options.

CONCLUSION

MCID evaluates outcomes relative to whether they provide a meaningful change to patients, incorporating the risks and benefits of a treatment. Using MCID in the process of evaluating outcomes helps to avoid the error of interpreting a small but statistically significant outcome difference as being clinically important.

Ketorolac plus Lidocaine vs Lidocaine for pain relief following core needle soft tissue biopsy: A CONSORT-compliant double-blind randomized controlled study

BACKGROUNDS

The main objective of this study was to compare the pain control efficacy of local administration of Lidocaine with or without the nonsteroidal anti-inflammatory drug, Ketorolac, and local conventional Lidocaine injection in core needle biopsy of the musculoskeletal tumor.

METHODS

The current study was a randomized, double-blind controlled clinical trial that included 128 patients with suspected musculoskeletal tumors. Patients were randomly assigned to either the Ketorolac plus Lidocaine (n = 64) or Lidocaine group (n = 64). The Ketorolac - Lidocaine combination syringe contained 30 mg Ketorolac and 2% Lidocaine - adrenaline dosage, and the Lidocaine syringe contained 2% Lidocaine - adrenaline dosage. The level of pain after core needle biopsy was evaluated for each patient at 1, 6, 12, 24, 48, and >48 hours by a Visual Analog Scale (VAS). The mean VAS changes over time were compared between the Ketorolac plus Lidocaine and Lidocaine groups using a linear mixed model.

RESULTS

baseline information including mean age of patients in Lidocaine group (51.5 ± 19.4 years) and in Lidocaine - Ketorolac combination group (50.1 ± 18 years), diagnosis (malignant, benign, metastatic, infection), tumor location (upper and lower extremities, back), VAS score 1-hour post-operation (mild and moderate pain) were noted. The VAS score ratings were significantly lower in Lidocaine - Ketorolac combination group when compared to the Lidocaine group during the 1 to 24 hours post-operation time period.

CONCLUSION

Patients receiving Lidocaine - Ketorolac combination dosage had significantly lower VAS scores, and these results confirm that local injection of Lidocaine - Ketorolac combination had a superior pain-controlling effect during the first 24 hours after the biopsy procedure in comparison to Lidocaine injection alone, as measured by VAS score scale.

Comparative study of verbal rating scale and numerical rating scale to assess postoperative pain intensity in the post anesthesia care unit: A prospective observational cohort study

ABSTRACT

Postsurgical patients usually have difficulty in answering the self-report pain scales due to the residual effects of anesthetic or sedative agents in the post-anesthesia care unit (PACU). A comparative analysis of pain assessment tools used in the PACU is lacking.In this prospective observational study, we compared the intensity of pain using the 11-point numeric rating scale (NRS) and the 4-category verbal rating scale (VRS) thrice, 5 minutes after PACU admission, 20 minutes after the first assessment, and just before discharge from the PACU in 200 patients undergone surgery. Spearman rank correlation analysis was used to investigate the correlation between 2 scales, and the weighted kappa (κ) coefficient was performed to evaluate inter-scale reliability. Response rates of the 2 scales were also compared.VRS and NRS were highly correlated during all 3 comparisons (r = 0.767, 0.714, and 0.653, respectively; P < .0001). Each category of VRS showed a statistically significant difference in pain intensity measured by NRS during all 3 assessments. Inter-scale reliability had a fair strength of agreement for all 3 measurements (weighted κ = 0.519, 95% CI: 0.421-0.618; weighted κ = 0.511, 95% C.I: 0.409-0.613; weighted κ = 0.452, 95% C.I: 0.352-0.551, respectively). VRS showed a higher response rate for PACU patients compared to NRS in all 3 measurements (96% vs 77.5%, 99% vs 81.5%, and 96.5% vs 86.5%, respectively; P < .0001).In the PACU, VRS is a reasonable and practical pain intensity measurement tool for postsurgical patients, considering the high correlation between VRS and NRS, and a higher response rate.

Lumbar disc herniation surgery: Is it worth adding interspinous spacer or instrumented fusion with regard to disc excision alone?

BACKGROUND

Discectomy is sometimes associated with recurrence of disc herniation and pain after surgery. The evidence to use an interspinous dynamic stabilization system or instrumented fusion in association with disc excision to prevent pain and re-operation remains controversial. In this study, we analyzed if adding interspinous spacer or fusion, offers advantages in relation to microdiscetomy alone.

METHODS

Patients with lumbar disc herniation were divided in 3 groups; microdiscectomy alone (MD), microdiscectomy plus interspinous spacer (IS) and open discectomy plus posterior lumbar interbody fusion (PLIF). The clinical efficacy was measured using the Owestry Disability Index (ODI). Other outcome parameters including visual analogue scale for pain (VAS) back and legs, length of stay, direct in-hospital cost, 90-day complication rate, and 1-year re-operation rate were also evaluated.

RESULTS

A total of 103 patients whose mean age was 39.1 (±8.5) years were included. A significant improvement of the ODI and VAS back and legs pain baseline score was detected in the 3 groups. After 1 year, no significant differences in ODI, VAS back and legs pain were found between the 3 groups. There was an increase of 169% of the total direct in- hospital cost in IS group and 287% in PLIF group, in relation to MD (p < 0.001). Length of stay was 86% higher in the IS group and 384% longer in the PLIF group compared to MD (p < 0.001). The 1 year re-operation rates were 5.6%, 10% and 16.2% (p = 0.33). Discectomy seems to be the main responsible for the clinical improvement, without the interspinous spacer or fusion adding any benefit. The addition of interspinous spacer or fusion increased direct in-hospital cost, length of stay, and did not protect against re-operation.

Normal Preoperative Images Do Not Indicate a Poor Outcome of Surgery for Coccydynia

STUDY DESIGN

This is a retrospective cohort study.

OBJECTIVE

To evaluate the long-term outcomes after surgery for refractory coccygodynia in patients with normal imaging studies compared with patients where imaging shows an anomaly.

SUMMARY OF BACKGROUND DATA

Patients with coccydynia who do not respond to conservative treatment will often profit from coccygectomy. Most surgeons employ plain radiographs or magnetic resonance imaging (MRI) in their preoperative work-up. These will often show anomalies, but in some cases they do not. We investigated whether these patients do less well than those with abnormal images.

METHODS

We operated on 184 patients with coccydynia during a 7-year period and 171 (93%) responded to follow-up questionnaires after 37 (range: 12-85) months. Images of 33 patients were normal and 138 showed some coccygeal pathology. Surgery was considered to have been unsuccessful when respondents stated at review that they were somewhat better, unchanged, or worse.

RESULTS

There were no clinically or statistically significant differences in outcome between the groups. Surgery was unsuccessful in 24% of patients with normal images and in 32% among those with abnormal images. The median pain scores (0-10) during the week before review were two (interquartile range [IQR]: 0-3) and one (IQR: 1-5) in the two groups respectively. Similar proportions in the two groups stated that they would not have consented to surgery if they had known the outcome in advance.

CONCLUSION

Patients with severe coccydynia who have not responded to conservative treatment should not be denied surgery only because their radiographs or MRI studies look normal.

LEVEL OF EVIDENCE

4.

Differences in Functional Treadmill Tests in Patients With Adult Symptomatic Lumbar Scoliosis Treated Operatively and Nonoperatively

STUDY DESIGN

Prospective longitudinal cohort.

OBJECTIVES

The aim of this study was to determine whether functional treadmill testing (FTT) demonstrates differences between patients treated operatively and nonoperatively for adult symptomatic lumbar scoliosis (ASLS).

SUMMARY OF BACKGROUND DATA

ASLS has become increasingly prevalent as the population ages. ASLS can be accompanied by neurogenic claudication, leading to difficulty walking. FTT may provide a functional tool to evaluate patients with ASLS.

METHODS

One hundred and eighty-seven patients who underwent nonoperative (n = 88) or operative treatment (n = 99) of ASLS with complete baseline and 2-year post-treatment FTTs and concurrent patient-reported outcomes were identified. FTT parameters included maximum speed, time to onset of symptoms, distance ambulated, time ambulated, and Back and Leg pain severity before and after testing.

RESULTS

At baseline, patients treated operatively reported worse post-FTT back pain (4.39 vs. 3.45, P = 0.032) than those treated nonoperatively, despite similar ODI, SRS-22 Pain and Activity domain scores. Mean time ambulated (+2.15 vs. -1.20 P = 0.001), pre-FTT back pain (+0.19 vs. -1.60, P < 0.000) and leg pain (+0.25 vs. -0.54, P = 0.024) improved in the operative group but deteriorated in the nonoperative group. On the 2-year follow-up FTT, both groups showed improvement in post-FTT back pain (-0.53 vs. -2.64, P < 0.000) and leg pain (-0.13 vs. -1.54, P = 0.001) severity but the improvement was statistically significantly greater in the operative compared to the nonoperative group.

CONCLUSION

FTT results at baseline were worse in patients treated operatively than those treated non-operatively. FTT may be a useful adjunct to assess treatment outcomes in patients with ASLS and may help surgeons counsel patients regarding expectations 2 years after operative or nonoperative treatment for ASLS. At 2-year follow-up, time ambulated deteriorated in patients treated nonoperatively but improved in patients treated operatively. Although both groups showed improvement in post-FTT Back and Leg pain at 2 years, the improvement was greater in the operative compared to the nonoperative group.

LEVEL OF EVIDENCE

2.

Critical NIH Resources to Advance Therapies for Pain: Preclinical Screening Program and Phase II Human Clinical Trial Network

Opioid-related death and overdose have now reached epidemic proportions. In response to this public health crisis, the National Institutes of Health (NIH) launched the Helping to End Addiction Long-term InitiativeSM, or NIH HEAL InitiativeSM, an aggressive, trans-agency effort to speed scientific solutions to stem the national opioid public health crisis. Herein, we describe two NIH HEAL Initiative programs to accelerate development of non-opioid, non-addictive pain treatments: The Preclinical Screening Platform for Pain (PSPP) and Early Phase Pain Investigation Clinical Network (EPPIC-Net). These resources are provided at no cost to investigators, whether in academia or industry and whether within the USA or internationally. Both programs consider small molecules, biologics, devices, and natural products for acute and chronic pain, including repurposed and combination drugs. Importantly, confidentiality and intellectual property are protected. The PSPP provides a rigorous platform to identify and profile non-opioid, non-addictive therapeutics for pain. Accepted assets are evaluated in in vitro functional assays to rule out opioid receptor activity and to assess abuse liability. In vivo pharmacokinetic studies measure plasma and brain exposure to guide the dose range and pretreatment times for the side effect profile, efficacy, and abuse liability. Studies are conducted in accordance with published rigor criteria. EPPIC-Net provides academic and industry investigators with expert infrastructure for phase II testing of pain therapeutics across populations and the lifespan. For assets accepted after a rigorous, objective scientific review process, EPPIC-Net provides clinical trial design, management, implementation, and analysis.

Emerging Clinical Technology: Application of Machine Learning to Chronic Pain Assessments Based on Emotional Body Maps

Depression and anxiety co-occur with chronic pain, and all three are thought to be caused by dysregulation of shared brain systems related to emotional processing associated with body sensations. Understanding the connection between emotional states, pain, and bodily sensations may help understand chronic pain conditions. We developed a mobile platform for measuring pain, emotions, and associated bodily feelings in chronic pain patients in their daily life conditions. Sixty-five chronic back pain patients reported the intensity of their pain, 11 emotional states, and the corresponding body locations. These variables were used to predict pain 2 weeks later. Applying machine learning, we developed two predictive models of future pain, emphasizing interpretability. One model excluded pain-related features as predictors of future pain, and the other included pain-related predictors. The best predictors of future pain were interactive effects of (a) body maps of fatigue with negative affect and (b) positive affect with past pain. Our findings emphasize the contribution of emotions, especially emotional experience felt in the body, to understanding chronic pain above and beyond the mere tracking of pain levels. The results may contribute to the generation of a novel artificial intelligence framework to help in the development of better diagnostic and therapeutic approaches to chronic pain.

Analgesic impact of buprenorphine transdermal patch in total hip arthroplasty: A randomized controlled trial protocol

BACKGROUND

The efficacy and safety of buprenorphine transdermal patch (BTP) has been well established in chronic pain, but data regarding acute postoperative pain relief is still very limited. Therefore, we design a prospective, randomized, controlled study to evaluate the effectiveness and safety of the BTP for postoperative analgesia in total hip arthroplasty.

METHODS

This study is designed as a single-center, prospective, double-blind, randomized controlled trial. Group A receives a 10 mg patch of buprenorphine at the conclusion of surgery which is continued for 14 days. Group B receives a conventional analgesic regimen, that is, IV paracetamol 1 mg every 8 hours alternating with parenteral tramadol 50 mg every 8 hours for the first 2 postoperative days followed by oral administration of the same drug still the end of 2 weeks. A total of 160 patients are needed with an allowance for 10% drop-out. The primary outcome of this noninferiority study is opioid consumption within the first 24 hours following surgery. The secondary outcomes included numerical rating scale scores at rest, postoperative complications, length of hospital stay, and patient satisfaction.

RESULTS

This trial is expected to be the largest randomized trial assessing the efficacy of BTP after primary total hip arthroplasty and powered to detect a potential difference in the primary outcome.

TRIAL REGISTRATION NUMBER

This study protocol was registered in Research Registry (researchregistry5524).

Pain Outcomes Following Microvascular Decompression for Drug-Resistant Trigeminal Neuralgia: A Systematic Review and Meta-Analysis

BACKGROUND

Microvascular decompression (MVD) is a potentially curative surgery for drug-resistant trigeminal neuralgia (TN). Predictors of pain freedom after MVD are not fully understood.

OBJECTIVE

To describe rates and predictors for pain freedom following MVD.

METHODS

Using preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, PubMed, Cochrane Library, and Scopus were queried for primary studies examining pain outcomes after MVD for TN published between 1988 and March 2018. Potential biases were assessed for included studies. Pain freedom (ie, Barrow Neurological Institute score of 1) at last follow-up was the primary outcome measure. Variables associated with pain freedom on preliminary analysis underwent formal meta-analysis. Odds ratios (OR) and 95% confidence intervals (CI) were calculated for possible predictors.

RESULTS

Outcome data were analyzed for 3897 patients from 46 studies (7 prospective, 39 retrospective). Overall, 76.0% of patients achieved pain freedom after MVD with a mean follow-up of 1.7 ± 1.3 (standard deviation) yr. Predictors of pain freedom on meta-analysis using random effects models included (1) disease duration ≤5 yr (OR = 2.06, 95% CI = 1.08-3.95); (2) arterial compression over venous or other (OR = 3.35, 95% CI = 1.91-5.88); (3) superior cerebellar artery involvement (OR = 2.02, 95% CI = 1.02-4.03), and (4) type 1 Burchiel classification (OR = 2.49, 95% CI = 1.32-4.67).

CONCLUSION

Approximately three-quarters of patients with drug-resistant TN achieve pain freedom after MVD. Shorter disease duration, arterial compression, and type 1 Burchiel classification may predict more favorable outcome. These results may improve patient selection and provider expectations.

The association between believing staying active is beneficial and achieving a clinically relevant functional improvement after 52 weeks: a prospective cohort study of patients with chronic low back pain in secondary care

BACKGROUND

According to clinical guidelines, advice to stay active despite experiencing pain is recommended to patients with non-specific low back pain (LBP). However, not all patients receive guideline-concordant information and advice, and some patients still believe that activity avoidance will help them recover. The purpose was to study whether guideline-concordant beliefs among patients and other explanatory variables were associated with recovery. The main aim was to investigate whether believing staying active despite having pain is associated with a better functional outcome.

METHODS

This was a prospective cohort study involving adults with non-specific LBP referred from general practices to the Spine Centre at Silkeborg Regional Hospital, Denmark. Patients reported on their beliefs about the importance of finding the cause, the importance of diagnostic imaging, perceiving to have received advice to stay active, pain duration, pain intensity, and STarT Back Tool. Agreeing to: 'An increase in pain is an indication that I should stop what I'm doing until the pain decreases' adjusted for age, gender, and education level was the primary explanatory analysis. A 30% improvement in the Roland Morris Disability Questionnaire (RMDQ) score after 52 weeks was the outcome.

RESULTS

816 patients were included and 596 (73.0%) agreed that pain is a warning signal to stop being active. Among patients not considering pain as a warning signal, 80 (43.2%) had a favourable functional improvement of ≥30% on the RMDQ compared to 201 (41.2%) among patients considering pain a warning signal. No difference was found between the two groups (adjusted P = 0.542 and unadjusted P = 0.629). However, STarT Back Tool high-risk patients had a less favourable functional outcome (adjusted P = 0.003 and unadjusted P = 0.002). Chronic pain was associated with less favourable functional outcome (adjusted P < 0.001 and unadjusted P < 0.001), whereas beliefs about finding the cause, diagnostic imaging, perceiving to have received advice to stay active, or pain intensity were not significantly associated with outcome.

CONCLUSIONS

Holding the single belief that pain is a warning signal to stop being active was not associated with functional outcome. However, patients characterised by having multiple psychological barriers (high-risk according to the STarT Back Tool) had a less favourable functional outcome.

TRIAL REGISTRATION

Registered at ClinicalTrials.gov (registration number: NCT03058315), 20 February 2017.

The Effect of Early Limited Activity after Bipedicular Percutaneous Vertebroplasty to Treat Acute Painful Osteoporotic Vertebral Compression Fractures

BACKGROUND

Although percutaneous vertebroplasty (PVP) can effectively relieve the pain for patients with acute osteoporotic vertebral compression fractures (OVCFs), many patients still complain of mild back pain in the early postoperative period.

OBJECTIVES

The aim of this study was to assess the effect of early limited activity (LA) on prognosis after bipedicular small-cement-volume (i.e., PVP) to treat single-segment acute OVCFs.

STUDY DESIGN

A prospective study and retrospective observations were performed on 125 patients with a minimum of 1 year of follow-up.

SETTING

A university hospital orthopedics and pathology departments.

METHODS

All patients were allocated into an LA group (n = 64) and an unlimited activity group (ULA group, n = 61). Patients in the LA group were suggested to keep time of off-bed activity < 4 hours per day in the first 3 weeks postoperatively. Patients in the ULA group did not limit activity. The demographic, clinical, and radiologic outcomes were assessed, such as pain intensity Numeric Rating Scale (NRS-11) and vertebral height ratio (i.e., fractured vertebral height/adjacent nonfractured vertebral height). Based on outcomes following surgery, all patients were classified as responders (NRS-11 score 1-day postoperation < 50% of preoperative NRS-11 score) or low responders (NRS-11 score 1-day postoperation >= 50% of preoperative NRS-11 score).

RESULTS

The demographic results and complications were similar. In the LA group, NRS-11 scores at 1 and 3 months postoperation respectively were 2.23 ± 0.42 and 1.46 ± 0.40, and corresponding scores respectively were 2.85 ± 0.80 and 1.73 ± 0.77 in the ULA group, and there was a difference in the 2 groups in both time points (P < 0.05). At 12 months postoperation, anterior and middle vertebral height ratio respectively were 78.42% ± 3.52% and 82.37% ± 3.49% in the LA group, which were higher than 76.87% ± 3.68% and 81.10% ± 3.31% in the ULA group (P < 0.05). Thirty-two cases were low responders. Among those, NRS-11 scores at 1 and 3 months postoperation respectively were 2.29 ± 0.45 and 1.53 ± 0.46 in the LA group, which were lower than 3.67 ± 0.80 and 2.56 ± 0.79 in the ULA group (P < 0.05), and at 12 months postoperation, anterior vertebral height ratio was 79.81% ± 3.25% in the LA group and 75.60% ± 3.50% in the ULA group (P < 0.05).

LIMITATIONS

First, some patients lacked the results of bone mineral density during follow-up; second, the limited time in our study was chosen from our previous working experience, which may lack an objective basis; third, NRS-11 is solely used as an indicator of clinical outcomes in our study; finally, our next studies can increase the sample size to improve the clinically difference.

CONCLUSIONS

LA in the early period after PVP can help patients achieve more pain relief postoperatively and maintain better vertebral shape, especially for low responders.

KEY WORDS

Osteoporotic vertebral compression fractures, percutaneous vertebroplasty, Numeric Rating Scale, vertebral height, responders, low responders, limited activity, complications.

Long-term efficacy of 1-1.2 kHz subthreshold spinal cord stimulation following failed traditional spinal cord stimulation: a retrospective case series

BACKGROUND AND OBJECTIVE

We investigated whether an effective long-term pain relief could be achieved using subthreshold 1-1.2 kHz spinal cord stimulation (SCS) among patients who were initially implanted with traditional paresthesia-based SCS but who failed to maintain an adequate pain relief.

METHODS

Retrospective chart review was conducted of patients' electronic records who underwent a trial of subthreshold 1-1.2 kHz SCS. One hundred and nine patients implanted and programmed at traditional paresthesia-based frequencies 40-90 Hz (low-frequency SCS) with unsatisfactory pain relief or unpleasant paresthesias were identified. Patients' settings were switched to 1-1.2 kHz and 60-210 µs, and variable amplitude adjusted to subthreshold. Pain scores and medication usage were collected. Complete data are presented on 95 patients.

RESULTS

Data were collected from 36 men and 59 women who were converted from above-threshold 40-90 Hz SCS to 1-1.2 kHz SCS, with a minimum follow-up of 12  months. Nearly a third (63/95 or 66.3%) of the subjects deemed 1-1.2 kHz SCS ineffective and returned to low-frequency SCS within 1 week after switch, and one-sixth (16/95 or 16.8%) of the subjects returned to low-frequency SCS within 1 month. Only 13 (13.7%) subjects continued using 1-1.2 kHz subthreshold SCS for 3 months or longer and 2.1% (2/95) of subjects continued using it at 12 months. A comparison of their pain scores and opioid use before and during the time we used 1-1.2 kHz SCS revealed no significant difference.

CONCLUSION

The results from our single center failed to show additional long-term clinical benefit of 1-1.2 kHz subthreshold SCS in patients with chronic pain failing traditional low-frequency SCS.

Calculated Decisions: Critical-care pain observation tool (CPOT)

The CPOT rates pain in critically ill patients by using clinical observations.

Calculated Decisions: Pain assessment in advanced dementia (PAINAD) scale

The PAINAD scale is used to assess pain in patients with dementia.

Pain Assessment in the Patient Unable to Self-Report: Clinical Practice Recommendations in Support of the ASPMN 2019 Position Statement

Pain is a subjective experience, unfortunately, some patients cannot provide a self-report of pain verbally, in writing, or by other means. In patients who are unable to self-report pain, other strategies must be used to infer pain and evaluate interventions. In support of the ASPMN position statement "Pain Assessment in the Patient Unable to Self-Report", this paper provides clinical practice recommendations for five populations in which difficulty communicating pain often exists: neonates, toddlers and young children, persons with intellectual disabilities, critically ill/unconscious patients, older adults with advanced dementia, and patients at the end of life. Nurses are integral to ensuring assessment and treatment of these vulnerable populations.

Weeding Out the Problem: The Impact of Preoperative Cannabinoid Use on Pain in the Perioperative Period

BACKGROUND

The recreational and medical use of cannabinoids has been increasing. While most studies and reviews have focused on the role of cannabinoids in the management of acute pain, no study has examined the postoperative outcomes of surgical candidates who are on cannabinoids preoperatively. This retrospective cohort study examined the impact of preoperative cannabinoid use on postoperative pain scores and pain-related outcomes in patients undergoing major orthopedic surgery.

METHODS

Outcomes of patients who had major orthopedic surgery at our hospital between April 1, 2015 and June 30, 2017 were reviewed. Data were obtained from Networked Online Processing of Acute Pain Information, a locally developed database for our Acute Pain Service. Propensity score matching was used to balance baselines variables including age, sex, type of surgery, history of depression or anxiety, and perioperative use of regional anesthesia between patients who reported use of cannabinoids and those not on this substance. Intensity of pain with movement in the early postoperative period (defined as up to 36 hours after surgery) was the primary outcome of this study. The secondary outcomes (all in early postoperative period) were pain at rest, opioid consumption, incidence of pruritus, nausea and vomiting, sedation, delirium, constipation, impairment of sleep and physical activity, patient satisfaction with analgesia, and the length of Acute Pain Service follow-up.

RESULTS

A total of 3793 patients were included in the study. Of these, 155 patients were identified as being on cannabinoids for recreational or medical indications in the preoperative period. After propensity score matching, we compared data from 155 patients who were on cannabinoids and 155 patients who were not on cannabinoids. Patients who were on preoperative cannabinoids had higher pain numerical rating score (median [25th, 75th percentiles]) at rest (5.0 [3.0, 6.1] vs 3.0 [2.0, 5.5], P = .010) and with movement (8.0 [6.0, 9.0] vs 7.0 [3.5, 8.5], P = .003), and a higher incidence of moderate-to-severe pain at rest (62.3% vs 45.5%, respectively, P = .004; odds ratio, 1.98; 95% CI, 1.25-3.14) and with movement (85.7% vs 75.2% respectively, P = .021; odds ratio, 1.98; 95% CI, 1.10-3.57) in the early postoperative period compared to patients who were not on cannabinoids. There was also a higher incidence of sleep interruption in the early postoperative period for patients who used cannabinoids.

CONCLUSIONS

This retrospective study with propensity-matched cohorts showed that cannabinoid use was associated with higher pain scores and a poorer quality of sleep in the early postoperative period in patients undergoing major orthopedic surgery.

Ultrasound therapy reduces persistent post-thoracotomy tactile allodynia and spinal substance P expression in rats

BACKGROUND

Therapeutic ultrasound (TU) alleviates nerve injury-associated pain, while the molecular mechanisms are less clear. This is an investigator-initiated experimental study to evaluate the mechanisms and effects of ultrasound on prolonged post-thoracotomy pain in a rodent model.

METHODS

The rats were randomly separated into four groups (n=8 per group): sham-operation (sham; group 1), thoracotomy and rib retraction (TRR; group 2), and TRR procedure followed by TU (TRR+TU-3; group 3) or TU with the ultrasound power turned off (TRR+TU-0; group 4). TU was delivered daily, beginning on postoperative day 11 (POD 11) for the next 2 weeks. Mechanical sensitivity, subcutaneous tissue temperature, and spinal substance P and interleukin-1 beta (IL-1β) were evaluated on PODs 11 and 23.

RESULTS

Group 3, which received ultrasound treatment (3 MHz; 1.0 W/cm²) for 5 min each day, demonstrated higher mechanical withdrawal thresholds when compared with the group without ultrasound intervention (group 2) or sham ultrasound (group 4). Ultrasound treatment also inhibited the upregulation of spinal substance P and IL-1β measured from spinal cord dorsal horns extract and increased subcutaneous temperature.

CONCLUSIONS

The results of this study suggest an increase in mechanical withdrawal thresholds and subcutaneous temperature, as well as a downregulation of spinal substance P and IL-1β, in the group which received ultrasound treatment. The regulation of spinal substance P and IL-1β may mediate potential effects of this non-invasive treatment.

Unilateral laminectomy for bilateral decompression improves low back pain while standing equally on both sides in patients with lumbar canal stenosis: analysis using a detailed visual analogue scale

BACKGROUND

Unilateral laminectomy for bilateral decompression (ULBD) for lumbar spinal stenosis (LSS) is a less invasive technique compared to conventional laminectomy. Recently, several authors have reported favorable results of low back pain (LBP) in patients of LSS treated with ULBD. However, the detailed changes and localization of LBP before and after ULBD for LSS remain unclear. Furthermore, unsymmetrical invasion to para-spinal muscle and facet joint may result in the residual unsymmetrical symptoms. To clarify these points, we conducted an observational study and used detailed visual analog scale (VAS) scores to evaluate the characteristics and bilateral changes of LBP and lower extremity symptoms.

METHODS

We included 50 patients with LSS treated with ULBD. A detailed visual analogue scale (VAS; 100 mm) score of LBP in three different postural positions: motion, standing, and sitting, and bilateral VAS score (approached side versus opposite side) of LBP, lower extremity pain (LEP), and lower extremity numbness (LEN) were measured. Oswestry Disability Index (ODI) was used to quantify the clinical improvement.

RESULTS

Detailed LBP VAS score before surgery was 51.5 ± 32.5 in motion, 63.0 ± 30.1 while standing, and 37.8 ± 31.8 while sitting; and showed LBP while standing was significantly greater than LBP while sitting (p < 0.01). After surgery, LBP while standing was significantly improved relative to that while sitting (p < 0.05), and levels of LBP in the three postures became almost the same with ODI improvement. Bilateral VAS scores showed significant improvement equally on both sides (p < 0.01).

CONCLUSIONS

ULBD improves LBP while standing equally on both sides in patients with LCS. The improvement of LBP by the ULBD surgery suggests radicular LBP improved because of decompression surgery. Furthermore, the symmetric improvement of LBP by the ULBD surgery suggests unsymmetrical invasion of the paraspinal muscles and facet joints is unrelated to residual LBP.

Acute abdominal pain-changes in the way we assess it over a decade

AIMS

Acute abdominal pain accounts for 5-10% of all emergency department visits. Rapid and accurate diagnosis is critical to ensure optimal outcomes. In the last decade, increased use of CT scans and the introduction of surgical short stay units has changed the way this group of patients is managed. The aim of this study was to evaluate the effects of these changes on patient management.

METHODS

A retrospective clinical study was undertaken including all patients admitted with abdominal pain under general surgery in the years 2004, 2009 and 2014. Two hundred from each of the three years were randomly selected and their care was reviewed.

RESULTS

During the study period, more patients were admitted under general surgery, from 1,462 in 2004 to 2,737 in 2014 (P=0.001). There was an increase in the proportion of patients admitted with non-surgical abdominal pain (25% in 2004 vs 34% in 2014, P=0.035). More computed tomography (CT) scans were performed (26.0% in 2004 vs 45.0% in 2014, P=0.001).

CONCLUSIONS

More patients were admitted under general surgery with abdominal pain and a greater proportion of these patients were admitted with non-surgical problems. Use of CT scans increased during the study period.

MiDAS ENCORE: Randomized Controlled Clinical Trial Report of 6-Month Results

BACKGROUND

Patients suffering from neurogenic claudication due to lumbar spinal stenosis (LSS) often experience moderate to severe pain and significant functional disability. Neurogenic claudication results from progressive degenerative changes in the spine, and most often affects the elderly. Both the MILD® procedure and epidural steroid injections (ESIs) offer interventional pain treatment options for LSS patients experiencing neurogenic claudication refractory to more conservative therapies. MILD provides an alternative to ESIs via minimally invasive lumbar decompression.

STUDY DESIGN

Prospective, multi-center, randomized controlled clinical trial.

SETTING

Twenty-six US interventional pain management centers.

OBJECTIVE

To compare patient outcomes following treatment with either MILD (treatment group) or ESIs (active control group) in LSS patients with neurogenic claudication and verified ligamentum flavum hypertrophy.

METHODS

This prospective, multi-center, randomized controlled clinical trial includes 2 study arms with a 1-to-1 randomization ratio. A total of 302 patients were enrolled, with 149 randomized to MILD and 153 to the active control. Six-month follow-up has been completed and is presented in this report. In addition, one year follow-up will be conducted for patients in both study arms, and supplementary 2 year outcome data will be collected for patients in the MILD group only.

OUTCOME MEASURES

Outcomes are assessed using the Oswestry Disability Index (ODI), numeric pain rating scale (NPRS) and Zurich Claudication Questionnaire (ZCQ). Primary efficacy is the proportion of ODI responders, tested for statistical superiority of the MILD group versus the active control group. ODI responders are defined as patients achieving the validated Minimal Important Change (MIC) of =10 point improvement in ODI from baseline to follow-up. Similarly, secondary efficacy includes proportion of NPRS and ZCQ responders using validated MIC thresholds. Primary safety is the incidence of device or procedure-related adverse events in each group.

RESULTS

At 6 months, all primary and secondary efficacy results provided statistically significant evidence that MILD is superior to the active control. For primary efficacy, the proportion of ODI responders in the MILD group (62.2%) was statistically significantly higher than for the epidural steroid group (35.7%) (P < 0.001). Further, all secondary efficacy parameters demonstrated statistical superiority of MILD versus the active control. The primary safety endpoint was achieved, demonstrating that there is no difference in safety between MILD and ESIs (P = 1.00).

LIMITATIONS

Limitations include lack of patient blinding due to considerable differences in treatment protocols, and a potentially higher non-responder rate for both groups versus standard-of-care due to study restrictions on adjunctive pain therapies.

CONCLUSIONS

Six month follow-up data from this trial demonstrate that the MILD procedure is statistically superior to epidural steroids, a known active treatment for LSS patients with neurogenic claudication and verified central stenosis due to ligamentum flavum hypertrophy. The results of all primary and secondary efficacy outcome measures achieved statistically superior outcomes in the MILD group versus ESIs. Further, there were no statistically significant differences in the safety profile between study groups. This prospective, multi-center, randomized controlled clinical trial provides strong evidence of the effectiveness of MILD versus epidural steroids in this patient population.

CLINICAL TRIAL REGISTRATION

NCT02093520.

A Seamless Navigation to ICD-10-CM for Interventional Pain Physicians: Is a Rude Awakening Avoidable?

Since October 1, 2015, the International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) was integrated into U.S. medical practices. This monumental transition seemingly occurred rather unceremoniously, despite significant opposition and reservations having been expressed by the provider community. In prior publications, we have described various survival strategies for interventional pain physicians. The regulators and beneficiaries of system-CMS, consultants, and health information technology industry are congratulating themselves for a job well done. Nonetheless, this transition comes at an immeasurable financial and psychological drain on providers. However, a rude awakening may be making its way with expiration of initial concessions from government and private payers.This manuscript provides a template for interventional pain management professionals with multiple steps for seamless navigation, including descriptions of the most commonly used codes, navigation through ICD-10-CM manual, steps for correct coding, and finally, detailed coding descriptions for various interventional techniques.

Is Platelet-Rich Plasma a Future Therapy in Pain Management?

Platelet-rich plasma (PRP) has the potential to regenerate tissues and decrease pain through the effects of bioactive molecules and growth factors present in alpha granules. Several PRP preparation systems are available with varying end products, doses of growth factors, and bioactive molecules. This article presents the biology of PRP, the preparation of PRP, and the effects PRP-related growth factors have on tissue healing and repair. Based on available evidence-based literature, the success of PRP therapy depends on the method of preparation and composition of PRP, the patient's medical condition, anatomic location of the injection, and the type of tissue injected.

Pain management trend of vaso-occulsive crisis (VOC) at a community hospital emergency department (ED) for patients with sickle cell disease

Pain management at the emergency department (ED) for vaso-occulsive crisis (VOC) for patients with sickle cell disease has not been optimum, with a long delay in giving the initial analgesic. We conducted a retrospective survey over a 7-year period to determine our ED's timing in giving pain medication to patients with VOC as a quality improvement project. We compared different periods, children vs adults, and the influence of gender in the analgesic administration timing. This is a retrospective chart review of three different periods: (1) years 2007-2008, (2) years 2011-2012, and (3) year 2013. We extracted relevant information from ED records. Data were analyzed using Student t test, chi-square analysis, and the Kruskal-Wallis test. There was a progressive improvement in the time interval to the 1st analgesic over these three periods. Children received analgesics more quickly than adults in all periods. Male adult patients received pain medication faster than female adult patients, although initial pain scores were higher in female than in male patients. Progressively fewer pediatric patients utilized ED over these three periods, but no difference for adult patients was observed. The proportion of pediatric patients admitted to the hospital increased with each period. The progressive decrease in both the number of patients and the number of visits to the ED by children suggested that the collective number of VOC in children has decreased, possibly secondary to the dissemination of hydroxyurea use. We failed to observe the same trend in adult patients. The need for IV access, and ordering laboratory tests or imaging studies tends to delay analgesic administration. Delay in administration of the first analgesic was more pronounced for female adult patients than male adult patients in spite of their higher pain score. Health care providers working in ED should make conscious efforts to respect pain in women as well as pain in men. Though not proven from this study, we believe that a significantly wider use of hydroxyurea by adult patients most likely would reduce their utilization of ED for the purpose of relief of pain, and further pediatric hematologists may be better positioned to increase hydroxyurea adherence by young adult patients, since they have had established rapport with them before transitioning to adult care.

Low back pain patients in Sweden, Denmark and the UK share similar characteristics and outcomes: a cross-national comparison of prospective cohort studies

BACKGROUND

Low back pain (LBP) is the world's leading cause of disability and yet poorly understood. Cross-national comparisons may motivate hypotheses about outcomes being condition-specific or related to cultural differences and can inform whether observations from one country may be generalised to another. This analysis of data from three cohort studies explored whether characteristics and outcomes differed between LBP patients visiting chiropractors in Sweden, Denmark and the UK.

METHODS

LBP patients completed a baseline questionnaire and were followed up after 3, 5, 12 and 26 weeks. Outcomes were LBP intensity (0-10 scales) and LBP frequency (0-7 days the previous week). Cohort differences were tested in mixed models accounting for repeated measures. It was investigated if any differences were explained by different baseline characteristics, and interaction terms between baseline factors and nations tested if strength of prognostic factors differed across countries.

RESULTS

The study sample consisted of 262, 947 and 453 patients from Sweden, Denmark and the UK respectively. Patient characteristics were largely similar across cohorts although some statistically significant differences were observed. The clinical course followed almost identical patterns across nations and small observed differences were not present after adjusting for baseline factors. The associations of LBP intensity and episode duration with outcome differed in strength between countries.

CONCLUSIONS

Chiropractic patients with low back pain had similar characteristics and clinical course across three Northern European countries. It is unlikely that culture have substantially different impacts on the course of LBP in these countries and the results support knowledge transfer between the investigated countries.

Postoperative Pain Surveys in Italy from 2006 and 2012: (POPSI and POPSI-2)

OBJECTIVE

Despite established standards, effective treatments, and evidence-based guidelines, postoperative pain control in Italy and other parts of the world remains suboptimal. Pain control has been recognized as a fundamental human right. Effective treatments exist to control postsurgical pain. Inadequate postoperative analgesia may prolong the length of hospital stays and may adversely impact outcomes.

MATERIALS AND METHODS

The same multiple-choice survey administered at the SIAARTI National Congress in Perugia in 2006 (n=588) was given at the SIAARTI National Congress in Naples, Italy in 2012 (n=635). The 2012 survey was analysed and compared to the 2006 results.

RESULTS

Postoperative pain control in Italy was less than optimal in 2006 and showed no substantial improvements in 2012. Geographical distinctions were evident with certain parts of Italy offering better postoperative pain control than other. Fewer than half of hospitals represented had an active Acute Pain Service (APS) and only about 10% of postsurgical patients were managed according to evidence-based guidelines. For example, elastomeric pumps for continuous IV infusion are commonly used in Italy, although patient-controlled analgesia systems are recommended in the guidelines. The biggest obstacles to optimal postoperative pain control reported by respondents could be categorized as organizational, cultural, and economic.

CONCLUSIONS

There is considerable room for improvement in postoperative pain control in Italy, specifically in the areas of clinical education, evidence-based treatments, better equipment, and implementation of active APS departments in more hospitals. Two surveys taken six years apart in Italy reveal, with striking similarity, that there are many unmet needs in postoperative pain control and that Italy still falls below European standards for postoperative pain control.

Increased dose of betamethasone for transforaminal epidural steroid injections is not associated with superior pain outcomes at 4 weeks

BACKGROUND

Fluoroscopically guided transforaminal epidural steroid injections (FG-TFESIs) have been shown to provide both immediate and long-term improvement in patient's self-reported pain. Administration of the lowest possible dose of epidural betamethasone is desired to minimize side effects while maintaining efficacy. We hypothesize that a 3 mg or a 6 mg dose of betamethasone will demonstrate equivalent analgesic properties.

OBJECTIVES

To compare the analgesic efficacy of 3 mg and a 6 mg dose of betamethasone for use in FG-TFESI.

STUDY DESIGN

Retrospective evaluation.

SETTING

Academic outpatient pain center.

METHODS

One hundred fifty-eight patients underwent FG-TFESI for lumbar back pain between 2012 and 2013. Depending on the date of service, a dose of 3 mg or a dose of 6 mg betamethasone was used in the single level unilateral TFESI. Opioid consumption and NRS pain score were analyzed pre-procedurally and at a clinic visit 4 weeks post-procedurally.

RESULTS

Changes in numerical rating scale (NRS) pain score (-1.21 +' 2.61 vs. -0.81 +' 2.40 respectively, P = 0.17) and changes in opioid consumption as measured in oral morphine equivalents (-2.94 +' 16.4 mg vs. -2.93 +' 14.8 mg, P = 0.17) were statistically equivalent between both groups. Intergroup sub-analysis of those with > 50% reduction in baseline VRS {sp} pain score was not different (15.2% vs. 34%, P = 0.56), and the proportion with a VRS pain score < 3 were similar (24.5% vs. 23.8%, P = 0.92).

LIMITATIONS

Potential selection bias inherent with study design.

CONCLUSIONS

Reduction in NRS pain scores and narcotic usage at 4 weeks after FG-TFESI were statistically equivalent between patients who received 3 mg or 6 mg of betamethasone, suggesting that a lower steroid dose has similar analgesic efficacy. IRB Number: Cedars Sinai Medical Center Institutional Review Board Pro00031594

Pain scores show no monotonic upward or downward trend over time

BACKGROUND

Self-reported pain scales are commonly used in emergency departments (EDs). The 11-point (0-10) numerical rating scale is a commonly used scale for adults visiting EDs in the United States. Despite their widespread use, little is known about whether distribution of pain scores has remained consistent over time.

OBJECTIVES

The objective of this study is to determine if there were upwards or downwards (monotonic) trends in pain scores over time at a single hospital.

METHODS

Retrospective chart review for the years 2003-2011. All pain scores for May 1(st) and 2(nd) of those years were collected. Multinomial logistic regression was used to model the probability of a patient rating their pain in each of 11 categories (scores 0 to 10) as a function of the calendar year. Additional analysis was carried out with pain scores grouped into four categories.

RESULTS

Data were collected from 2934 patient charts. Pain scores were recorded in 2136 charts, and 1637 of these pain scores were above zero (i.e., 1-10). The pain score distribution differed significantly over time (p = 0.001); however, there was no monotonic (single-direction) trend.

CONCLUSION

Although there were significant shifts in pain scores over time, there is not a significant monotonic trend. At this hospital, there was no "inflation" or "deflation" in pain scores over time. Shifts in distribution, even when not in a single direction, may be important for researchers examining pain scores in the ED.

Neuropsychology of migraine: present status and future directions

Migraine is recognized as a primarily neural condition. Changes in neural physiology have been consistently identified in migraineurs. Numerous studies are available that evaluate physical and functional differences between migraineurs and headache-free controls. The most prominent neuroimaging findings reported in migraine sufferers have been white matter changes. However, physical changes on neuroimaging have not been clearly correlated with functional impairment in migraineurs. The current literature addressing the neuropsychologic consequences of migraine has been far from conclusive, and reports of cognitive testing in adult migraineurs and controls has yielded inconsistent results. Neuropsychologic testing suggests that there may be some subtle but possibly significant changes in cognition that occur both during and between migraine episodes. A finding emerging with some consistency is that migraine patients with aura experience more neuropsychologic deficits than migraine patients without aura. The few studies that assess nonmigraine headache suggest that physical changes may not be unique to migraine, although neuropsychologic changes do appear to be limited to migraineurs. An examination of the unmet needs and priorities for future research addressing this important topic is provided.

Do minimally invasive procedures have a place in the treatment of chronic low back pain?

Chronic low back pain is the leading cause of disability in the industrialized world. Medical and surgical treatments remain costly despite limited efficacy. The field of 'interventional pain' has grown enormously and evidence-based practice guidelines are systematically developed. In this article, the vast, complex and contradictory literature regarding the treatment of chronic low back pain is reviewed. Interventional pain literature suggests that there is moderate evidence (small randomized, nonrandomized, single group or matched-case controlled studies) for medial branch neurotomy and limited evidence (nonexperimental one or more center studies) for intradiscal treatments in mechanical low back pain. There is moderate evidence for the use of transforaminal epidural steroid injections, lumbar percutaneous adhesiolysis and spinal endoscopy for painful lumbar radiculopathy, and spinal cord stimulation and intrathecal pumps mostly after spinal surgery. In reality, there is no gold standard for the treatment of chronic low back pain, but these results appear promising.

IASP global year against pain in older persons: highlighting the current status and future perspectives in geriatric pain

This year represents the international year against pain in older persons and it is opportune, therefore, to reflect upon the current status and possible future directions in pain-management practice for this large and growing segment of the population. Epidemiologic studies show a very high prevalence of persistent pain, often exceeding 50% of community-dwelling older persons and up to 80% of nursing home residents. Recently, there has been a major push to develop age-appropriate pain assessment tools, including several observer-rated scales of behavioral pain indicators for use in those with dementia. There has also been the release of several comprehensive guidelines for the assessment and management of pain in older persons, although the current evidence-base used to guide clinical practice is extremely limited. Unfortunately, despite these advances, pain remains grossly under treated in older persons, regardless of the healthcare setting. With the demographic imperative of a rapidly aging society, much greater attention is now being devoted to the problem of geriatric pain, with new initiatives in healthcare planning, calls for better professional education in geriatrics and pain management as well as new directions and funding resources for research into this important problem. Of course, this increased awareness must still be translated into action, not just because better pain relief for older adults is an ethically desirable outcome, but out of the sheer necessity of dealing with the millions of older persons who will suffer from persistent and bothersome pain in the years to come.

Pain prevalence and trajectories following pediatric spinal fusion surgery

Factors contributing to pain following surgery are poorly understood, with previous research largely focused on adults. With approximately 6 million children undergoing surgery each year, there is a need to study pediatric persistent postsurgical pain. The present study includes patients with adolescent idiopathic scoliosis undergoing spinal fusion surgery enrolled in a prospective, multicentered registry examining postsurgical outcomes. The Scoliosis Research Society Questionnaire-Version 30, which includes pain, activity, mental health, and self-image subscales, was administered to 190 patients prior to surgery and at 1 and 2 years postsurgery. A subset (n = 77) completed 5-year postsurgery data. Pain prevalence at each time point and longitudinal trajectories of pain outcomes derived from SAS PROC TRAJ were examined using analyses of variance and post hoc pairwise analyses across groups. Thirty-five percent of patients reported pain in the moderate to severe range presurgery. One year postoperation, 11% reported pain in this range, whereas 15% reported pain at 2 years postsurgery. At 5 years postsurgery, 15% of patients reported pain in the moderate to severe range. Among the 5 empirically derived pain trajectories, there were significant differences on self-image, mental health, and age. Identifying predictors of poor long-term outcomes in children with postsurgical pain may prevent the development of chronic pain into adulthood.

PERSPECTIVE

This investigation explores the prevalence of pediatric pain following surgery, up to 5 years after spinal fusion surgery. Five pain trajectories were identified and were distinguishable on presurgical characteristics of age, mental health, and self-image. This is the largest study to examine longitudinal pediatric pain trajectories after surgery.

Influence of random measurement error on estimated rates of headache chronification and remission

OBJECTIVE

To examine the potential influence of random measurement error on estimated rates of chronification and remission.

BACKGROUND

Studies of headache chronification and remission examine the proportion of headache sufferers that move across a boundary of 15 headache days per month between 2 points in time. At least part of that apparent movement may represent measurement error or random variation in headache activity over time.

METHODS

A mathematical simulation was conducted to examine the influence of varying degrees of measurement error on rates of chronic migraine onset and remission. Using data from the American Migraine Prevalence and Prevention Study, we estimated a starting distribution of headache days from 0 to 30 in the migraine population. Assuming various levels of measurement error, we then simulated 2 sets of data for Time 1 and Time 2. The "individuals" in this study were assumed to have no real change in headache frequency from Time 1 to Time 2. The observed variations in headache frequency were those influenced by imputed random variance to resemble typical measurement error or natural variability. Using this simulation approach, we estimated the amount of chronification and remission rates that might be attributed simply to statistical artifacts such as unreliability or regression to the mean.

RESULTS

As the degree of measurement error increased, the amounts of illusory chronification and remission increased substantially. For example, if the headache frequency of sufferers randomly varies by only 2 headache days each month due to chance alone, a substantial degree of illusory chronification (0.6% to 1.3%) and illusory remission (10.3% to 23.5%) rates are expected simply due to random variation.

CONCLUSIONS

Random variation, without real change, has the potential to influence estimated rates of progression and remission in longitudinal migraine studies. The magnitude of random variation needed to fully reproduce observed rates of progression and remission are implausibly large. Recommendations are offered to improve estimation of rates of progression and remission, reducing the influence of random variation.

The evolution and practice of acute pain medicine

BACKGROUND

In recent years, the field of acute pain medicine (APM) has witnessed a surge in its development, and pain has begun to be recognized not merely as a symptom, but as an actual disease process. This development warrants increased education of residents both in the performance of regional anesthesia as well as in the disease course of acute pain and the biopsychosocial mechanisms that define interindividual variability.

REVIEW SUMMARY

We reviewed the organization and function of the modern APM program. Following a discussion of the nomenclature of acute pain-related practices, we discuss the historical evolution and modern role of APM teams, including the use of traditional, as well as complementary and alternative, therapies for treating acute pain. Staffing and equipment requirements are also evaluated, in addition to the training requirements for achieving expertise in APM. Lastly, we briefly explore future considerations related to the essential role and development of APM.

CONCLUSION

The scope and practice of APM must be expanded to include pre-pain/pre-intervention risk stratification and extended through the phase of subacute pain.

Advances in translational neuropathic research: example of enantioselective pharmacokinetic-pharmacodynamic modeling of ketamine-induced pain relief in complex regional pain syndrome

Historically, complex regional pain syndrome (CRPS) was poorly defined, which meant that scientists and clinicians faced much uncertainty in the study, diagnosis, and treatment of the syndrome. The problem could be attributed to a nonspecific diagnostic criteria, unknown pathophysiologic causes, and limited treatment options. The two forms of CRPS still are painful, debilitating disorders whose sufferers carry heavy emotional burdens. Current research has shown that CRPS I and CRPS II are distinctive processes, and the presence or absence of a partial nerve lesion distinguishes them apart. Ketamine has been the focus of various studies involving the treatment of CRPS; however, currently, there is incomplete data from evidence-based studies. The question as to why ketamine is effective in controlling the symptoms of a subset of patients with CRPS and not others remains to be answered. A possible explanation to this phenomenon is pharmacogenetic differences that may exist in different patient populations. This review summarizes important translational work recently published on the treatment of CRPS using ketamine.

Long-term reliable change of pain scores in individual myogenous TMD patients

A within-patient change in pain score after treatment is statistically 'reliable' when it exceeds the smallest detectable difference (SDD). The aims of the present study were to: (i) determine SDDs for VAS-scores of pain intensity, for sufficiently long test-retest intervals to include most biological fluctuations, (ii) examine whether SDD is invariant to baseline score, and (iii) discuss the value of reliable change (RC) for detecting clinically important difference (CID) or as a possible indicator of successful treatment. SDDs were determined using duplicate data from 118 patients with myogenous Temporomandibular disorders: (1) VAS-scores of pain intensity from the masticatory system in a pre-treatment diary, and (2) VAS-scores of pain intensity from the hand (cold-pressor test). RC was determined in VAS-scores from a pre- and post-treatment questionnaire. The long-term SDD was 49mm. A regression analysis on duplicate VAS-scores showed that SDD was largely invariant to the baseline level. Because RC (change>SDD) exceeded CID, it might serve as an indicator of successful treatment. However, only 17% of the patients showed RC after treatment, mainly because the baseline was smaller than SDD in 67% of the patients thus making detection of any treatment effect impossible. For patients with possible detection (33%), the frequency of RC was 51%. If the detection threshold would be avoided by provoking pain in patients with a low baseline, a long-term RC in VAS-scores might occur in about half of all myogenous TMD patients and might then serve as an indicator of cases of treatment success.

How nursing personnel judge patients’ pain

The study examined how nurses, student nurses, and nurse's aides judge patients' level of pain from five indicators: facial grimacing, maintenance of abnormal body position, restriction of movement, complaints about pain, and signs of possible depression. In Toulouse, France, 214 participants were presented with 48 vignettes describing an elderly patient suffering from osteoarthritis who showed various levels of these signs. The three most important factors in judging pain were the difficulty in making social contact with the patient, the patient's avoidance of changing position, and her avoidance of movements. The nurses put more emphasis on the difficulty in making social contact than did the student nurses and nurse's aides. In all groups, each sign of pain contributed independently and additively to the level of pain that the patient was thought to be experiencing.

[Investigation of pain assessment trends among residents in Japanese long-term care facilities]

AIM

Pain management is vital for both the maintenance and improvement of the quality of life of residents, in Japanese long-term care facilities. However, few studies examining pain assessment in older populations have been published. The purpose of this study is to investigate the actual conditions related to pain assessment of residents by nurses in Japanese long-term care facilities. Included in this investigation are the actual frequency of pain assessments, the nurses own perceptions of the pain assessment of their residents, whether or not nurses have undertaken any training related to pain assessment, and the need for a pain assessment training period.

METHODS

A questionnaire was distributed to 487 nurses in 60 Japanese long-term care facilities.

RESULTS

A total of 443 valid responses were collected. The data revealed that 74.7% of these nurses lack the confidence to suitably assess the residents' pain and 44.2% of these nurses do not conduct pain assessments on a regular basis. Additionally, only 9.9% of the nurses surveyed have participated in seminars concerning pain in older people.

CONCLUSION

The results indicate that over 70% of nurses lack the confidence to suitably assess their residents' pain. In addition, the number of residents who cannot self-report their pain because of cognitive impairment is increasing. Therefore, it is necessary to develop new approaches which provide nurses with sufficient knowledge and confidence to conduct appropriate pain assessments on their residents.

Pain assessment: subjectivity, objectivity, and the use of neurotechnology

The pain clinician is confronted with the formidable task of objectifying the subjective phenomenon of pain so as to determine the right treatments for both the pain syndrome and the patient in whom the pathology is expressed. However, the experience of pain - and its expression - remains enigmatic. Can currently available evaluative tools, questionnaires, and scales actually provide adequately objective information about the experiential dimensions of pain? Can, or will, current and future iterations of biotechnology - whether used singularly or in combination (with other technologies as well as observational-behavioral methods) - afford objective validation of pain? And what of the clinical, ethical, legal and social issues that arise in and from the use - and potential misuse - of these approaches? Subsequent trajectories of clinical care depend upon the findings gained through the use of these techniques and their inappropriate employment - or misinterpretation of the results they provide - can lead to misdiagnoses and incorrect treatment. This essay is the first of a two-part series that explicates how the intellectual tasks of knowing about pain and the assessment of its experience and expression in the pain patient are constituent to the moral responsibility of pain medicine. Herein, we discuss the problem of pain and its expression, and those methods, techniques, and technologies available to bridge the gap between subjective experience and objective evaluation. We address how these assessment approaches are fundamental to apprehend both pain as an objective, neurological event, and its impact upon the subjective experience, existence, and expectations of the person in pain. In this way, we argue that the right use of technology - together with inter-subjectivity, compassion, and insight - can sustain the good of pain care as both a therapeutic and moral enterprise.

An interdisciplinary clinical practice model for the management of low-back pain in primary care: the CLIP project

BACKGROUND

Low-back pain is responsible for significant disability and costs in industrialized countries. Only a minority of subjects suffering from low-back pain will develop persistent disability. However, this minority is responsible for the majority of costs and has the poorest health outcomes. The objective of the Clinic on Low-back pain in Interdisciplinary Practice (CLIP) project was to develop a primary care interdisciplinary practice model for the clinical management of low-back pain and the prevention of persistent disability.

METHODS

Using previously published guidelines, systematic reviews and meta-analyses, a clinical management model for low-back pain was developed by the project team. A structured process facilitating discussions on this model among researchers, stakeholders and clinicians was created. The model was revised following these exchanges, without deviating from the evidence.

RESULTS

A model consisting of nine elements on clinical management of low-back pain and prevention of persistent disability was developed. The model's two core elements for the prevention of persistent disability are the following: 1) the evaluation of the prognosis at the fourth week of disability, and of key modifiable barriers to return to usual activities if the prognosis is unfavourable; 2) the evaluation of the patient's perceived disability every four weeks, with the evaluation and management of barriers to return to usual activities if perceived disability has not sufficiently improved.

CONCLUSION

A primary care interdisciplinary model aimed at improving quality and continuity of care for patients with low-back pain was developed. The effectiveness, efficiency and applicability of the CLIP model in preventing persistent disability in patients suffering from low-back pain should be assessed.

Pain management and health care policy

Opioid analgesics are essential for the management of moderate to severe pain. In spite of their documented effectiveness, opioids are often underutilized, a factor which has contributed significantly to the undertreatment of pain. Many countries have developed true national policies on cancer pain and palliative care, and in others only guidelines for care have been developed. Ideally, national policies facilitate and legislate not only a patient's right to care, but also the necessary components of education and drug availability which are so critical for the appropriate achievement of public health programs.

Revelation of a personal placebo response: its effects on mood, attitudes and future placebo responding

While ethics of placebo use has been debated since discovery of the phenomena, there has yet to be a study that examines the aftereffect of individuals learning of a personal placebo response on their future ability to experience a placebo response. In the first study, eleven participants diagnosed with irritable bowel syndrome in a placebo study were interviewed individually about their personal placebo response. We found no changes in attitudes about the likelihood of using medical and non-medical treatments for pain, likelihood of participating in future studies or likeability and trust of experimenters. In addition, we found no changes in mood except for a slight improvement in frustration. In the second study, 77 undergraduate students from the University of Florida were divided into three conditions: placebo, control and repeated baseline. We used a double placebo design with verbal placebo suggestion and conditioning to induce a placebo response and to examine the effect of providing information about a participant's personal placebo response on their future placebo response. Using a heat thermode, we discovered that there were no differences in future pain responding between participants who were told that they experienced a placebo response versus those who were not. In addition, similar to the first study, we found no detrimental effects of the placebo information variables measured. These studies suggest the placebo response persists even after revelation of a personal placebo response and placebo use does not appear to cause adverse effects on mood and other attitude variables assessed.