Classification and measurement of pain in the spinal cord-injured population

The interrelationship between pain, life satisfaction and mental health in adults with traumatic spinal cord injury, in the context of a developing country

STUDY DESIGN

Cross-sectional, analytical study design using a conveneient sampling strategy.

OBJECTIVES

To examine the interrelationship between pain, life satisfaction and indices of negative mental well-being amongst the traumatic spinal cord injury (TSCI) population.

SETTING

Western Cape Rehabilitation Center in Cape Town, South Africa.

METHODS

Participants (n = 70) were adults (mean age of 36.3, SD = 9.2) with TSCI. Participants completed the following instruments: 10 satisfaction items from the World Health Organization Quality of Life Brief Version, short forms of the Center for Epidemiological Studies Depression Scale and the trait scale of the State-Trait Anxiety Inventory, a one-item measure of pain intensity taken from the International Spinal Cord Injury Pain Basic Data Set and the interference scale of the Brief Pain Inventory.

RESULTS

Correlational analysis (Pearson r) demonstrated that all the indices of mental well-being as well as the two indices of pain was significantly negatively related to life satisfaction. In addition, life satisfaction mediated the relationship between pain intensity and depression as well as anxiety. Life satisfaction only mediated the relationship between pain interference and depression but not anxiety.

CONCLUSIONS

An improvement in life satisfaction may lead to improvements in pain interference, pain intensity as well as psychological distress, amongst persons suffering from TSCI Future research should focus on assessing measures/treatment which may improve life satisfaction in the TSCI population.

Prevention of posttraumatic stress during inpatient rehabilitation post spinal cord injury: Study protocol for a randomized controlled trial of Brief Prolonged Exposure Therapy (Brief PE)

Background

Scant research has focused on posttraumatic stress disorder (PTSD) in the SCI population, despite high prevalence estimates. Fortunately, prolonged exposure therapy (PE) is a well-researched and highly effective treatment for PTSD. Our recent clinical trial showed that standard 12-session PE was effective for PTSD treatment among inpatients with SCI. Early intervention with brief PE (3-sessions) delivered in the emergency department has also been effective for PTSD prevention, but has not been tested among people post-SCI. Thus, we aim to conduct the first test of the Brief PE intervention to prevent PTSD among patients with SCI.

Methods

Adults who have experienced a SCI (N = 200) will be randomly assigned during inpatient rehabilitation to either: (a) 3 60-min sessions of Brief PE (intervention group) or (b) treatment as usual (control group).

Results

The primary outcome measure (PTSD symptoms measured by the PSSI-5) and secondary outcome measures (depression, anxiety, pain, quality of life, sleep disturbance, and resilience) will be assessed at baseline, 1-month, 3-months, and 6-months. Hierarchical linear modeling (HLM) will be used to evaluate the effectiveness of the PE intervention on PTSD and secondary outcomes. Descriptive statistics will examine feasibility and will include the number of participants enrolled, the number of sessions completed, fidelity of Brief PE delivery, and average scores for difficulty and helpfulness of the intervention scales for those randomized to intervention.

Conclusions

Successful completion of this study will provide an evidence-based program to alleviate posttraumatic distress post spinal cord injury and prevent long-term development of PTSD.

A pilot study to evaluate micro-fragmented adipose tissue injection under ultrasound guidance for the treatment of refractory rotator cuff disease in wheelchair users with spinal cord injury

CONTEXT/OBJECTIVES

Wheelchair users with chronic shoulder pain have few options after conservative treatments fail. This pilot study's purpose was to establish safety and treatment effects of micro-fragmented adipose tissue (MFAT) injections under ultrasound guidance for treatment of refractory shoulder pain caused by rotator cuff disease in wheelchair users with spinal cord injury (SCI) to prepare for a larger trial.

DESIGN

Pilot clinical trial.

SETTING

Rehabilitation hospital outpatient clinic.

PARTICIPANTS

Ten wheelchair users with chronic SCI who had moderate-to-severe shoulder pain caused by refractory rotator cuff disease (diagnosed via ultrasound) for greater than 6 months.

INTERVENTIONS

Ultrasound-guided injections of MFAT into the pathologic rotator cuff tendons and other abnormal shoulder structures (e.g. acromioclavicular and glenohumeral joints; subacromial bursa).

OUTCOME MEASURES

6- and 12-month changes in 11-point Numerical Rating Scale (NRS); Wheelchair User's Shoulder Pain Index (WUSPI); Brief Pain Inventory pain interference items (BPI-I7); Patient Global Impression of Change (PGIC); ultrasound and physical exams; and adverse events.

CONCLUSIONS

There were no significant adverse events throughout the study period. WUSPI, NRS, and BPI-I7 scores were significantly lower 6 and 12 months post-procedure (P < .05). Of those who remained in the trial, clinically meaningful changes (≥30% decrease) in WUSPI, NRS, and BPI-I7 scores were observed in 77.8%, 77.8%, and 66.7% of participants, respectively. All but one participant reported improvement in clinical status. MFAT injection under ultrasound guidance is potentially a safe and efficacious treatment for refractory shoulder pain caused by rotator cuff disease in wheelchair users with SCI. A larger, randomized controlled trial has been initiated.Trial registration: ClinicalTrials.gov identifier: NCT03167138.

Prolonged exposure therapy for PTSD among spinal cord injury survivors: Study protocol for a randomized controlled trial

The National Spinal Cord Injury Statistical Center estimates 294,000 people in the US live with a spinal cord injury (SCI), with approximately 17,810 new cases each year. Although the physical outcomes associated with SCI have been widely studied, the psychological consequences of sustaining a SCI remain largely unexplored. Scant research has focused on posttraumatic stress disorder (PTSD) in this population, despite prevalence estimates suggesting that up to 60% of individuals with SCI experience PTSD post-injury, compared to only 7% of the general US population. Fortunately, prolonged exposure therapy (PE) is a well-researched and highly effective treatment for PTSD. However, no trauma focused exposure-based therapy for PTSD (e.g. PE) has not yet been tested in a SCI population. Thus, we aim to conduct the first test of an evidence-based intervention for PTSD among patients with SCI. Adults with SCI and PTSD (N = 60) will be randomly assigned to either: (1) 12-sessions of PE (2-3 sessions per week) or (2) a treatment as usual (TAU) control group who will receive the standard inpatient rehabilitation care for SCI patients. Primary outcomes will be assessed at 0, 6, 10, and 32 weeks.

Neuropathic pain after spinal cord injury and physical exercise in animal models: A systematic review and meta-analysis

The aim of this systematic review was to summarize the effects of physical exercise on neuropathic pain (NP) in animal models of SCI. The search was conducted in Medline and Science Direct to identify experimental preclinical studies involving animal models of SCI, physical exercise as an intervention and the assessment of NP. Fifteen articles met the eligibility criteria. The review shows that in studies of NP involving animal models of SCI, rodents are the most common species. Thoracic contusion is the most common injury and mechanical and thermal nociception are the most frequently assessed NP components. The benefits of physical exercise vary according to its starting period and total duration. In addition, there is considerable heterogeneity regarding the type and intensity of exercise capable of alleviating NP after SCI. Furthermore, physical exercise has beneficial effects on mechanical, thermal and cold nociception, and spontaneous pain. These results are weakened by the paucity of studies involving these pain outcomes. The review protocol is published for free access on the SyRF platform (http://syrf.org.uk/protocols/).

A randomized controlled trial of botulinum toxin A for treating neuropathic pain in patients with spinal cord injury

BACKGROUND

To assess the effect of botulinum toxin A (BTA) for treating neuropathic pain in patients with spinal cord injury (SCI).

METHODS

A total of 44 patients with SCI with neuropathic pain were randomly divided into the intervention group and the placebo group, each group 21 patients. The subjects in the intervention group received BTA (200 U subcutaneous injection, once daily) at the painful area, whereas those in the placebo group were administered a saline placebo. This study was conducted from December 2014 to November 2016. The primary outcome was measured using the visual analog scale (VAS). The secondary outcomes were measured using the short-form McGill Pain Questionnaire (SF-MPQ), and World Health Organization quality of life (WHOQOL-BREF) questionnaire. All outcome measurements were performed before and after 4 and 8 weeks of intervention.

RESULTS

Forty-one participants completed the study. The intervention with BTA showed greater efficacy than placebo in decreasing the VAS score after week 4 and week 8 of treatment. Significant differences in the SF-MPQ and WHOQOL-BREF were also found between the 2 groups.

CONCLUSION

The results of this study demonstrated that BTA might decrease intractable neuropathic pain for patients with SCI.

Thermal nociception using a modified Hargreaves method in primates and humans

Nociception is an important protective mechanism. The Hargreaves method, which involves measuring withdrawal latency following thermal stimulation to Thermal nociception using a modified Hargreaves method in primates and humans the paw, is commonly used to measure pain thresholds in rodents. We modified this technique to measure pain thresholds in monkeys and humans. The modified Hargreaves method was used to quantitate pain sensitivity in eight normal rhesus monkeys, 55 human volunteers, and 12 patients with spinal cord or cauda equina lesions. Thermal stimulation was delivered at 80% of maximum output, and the duration of the stimulation was set at a maximum of 10 seconds to avoid skin injury. The following withdrawal latencies were recorded: 2.7 ± 0.12 seconds in volunteers and 3.4 ± 0.35 seconds in neurologically intact monkeys (p>0.05). Patients with spinal cord or cauda equina lesions showed significantly increased latencies (p<0.001). The modified Hargreaves technique is a safe and reliable method that can provide a validated measure of physiological pain sensation.

Botulinum toxin type A for neuropathic pain in patients with spinal cord injury

Objective

To evaluate the analgesic effect of botulinum toxin type A (BTX‐A) on patients with spinal cord injury‐associated neuropathic pain.

Methods

The effect of BTX‐A on 40 patients with spinal cord injury‐associated neuropathic pain was investigated using a randomized, double‐blind, placebo‐controlled design. A 1‐time subcutaneous BTX‐A (200U) injection was administered to the painful area. Visual analogue scale (VAS) scores (0–100mm), the Korean version of the short‐form McGill Pain Questionnaire, and the World Health Organization WHOQOL‐BREF quality of life assessment were evaluated prior to treatment and at 4 and 8 weeks after the injection.

Results

At 4 and 8 weeks after injection, the VAS score for pain was significantly reduced by 18.6 ± 16.8 and 21.3 ± 26.8, respectively, in the BTX‐A group, whereas it was reduced by 2.6 ± 14.6 and 0.3 ± 19.5, respectively, in the placebo group. The pain relief was associated with preservation of motor or sensory function below the neurological level of injury. Among the responders in the BTX‐A group, 55% and 45% reported pain relief of 20% or greater at 4 and 8 weeks, respectively, after the injection, whereas only 15% and 10% of the responders in the placebo group reported a similar level of pain relief. Improvements in the score for the physical health domain of the WHOQOL‐BREF in the BTX‐A group showed a marginal trend toward significance (p = 0.0521) at 4 weeks after the injection.

Interpretation

These results indicate that BTX‐A may reduce intractable chronic neuropathic pain in patients with spinal cord injury. Ann Neurol 2016;79:569–578

Spasticity changes in SCI following a dynamic standing program using the Segway

STUDY DESIGN

A pilot prospective pre- and post-intervention study.

OBJECTIVES

To determine whether a dynamic standing program using the Segway Personal Transporter results in any measurable physiological effects in individuals with spinal cord injury (SCI) using both qualitative and quantitative measures of spasticity, pain and fatigue.

SETTING

International Collaboration of Repair Discoveries (ICORD) Research Centre, Vancouver, BC, Canada.

METHODS

Eight individuals with SCI ASIA (American Spinal Injury Association) A-D, who could stand with or without the assistance of bracing or supports, participated in a 4-week dynamic standing program using a Segway (3 per week, 30-min sessions). The main outcome was spasticity as measured by the Modified Ashworth Scale (MAS). Secondary measures included the SCI-Spasticity Evaluation Tool, Pain Outcomes Questionnaire, and Fatigue Severity Scale.

RESULTS

The dynamic standing sessions were associated with immediate improvements in spasticity (MAS) (P<0.001) and self-reported pain (P<0.05). Fatigue levels decreased, however this was not significant. There is little evidence to suggest that these beneficial outcomes may have lasting effects.

CONCLUSIONS

Dynamic standing on the Segway may be effective for short-term spasticity reduction and decreased pain and fatigue. Future work should examine a larger sample size and help to propose mechanisms for potential reductions in spasticity.

The relationship between prescription medication use and ability to ambulate distances after spinal cord injury

OBJECTIVE

To investigate the relationship between prescription medication use for pain and spasticity and ambulation distances while controlling for pain severity, injury severity, age, sex, and race in participants with spinal cord injury (SCI).

DESIGN

Secondary analysis of survey data.

SETTING

Specialty hospital in the Southeast United States.

PARTICIPANTS

Adults (N=407) with traumatic SCI identified through inpatient and outpatient hospital databases.

INTERVENTION

Not applicable.

MAIN OUTCOMES MEASURES

A questionnaire measured prescription medication use, ambulation distance, and other demographic data. A composite score of four 10-point scales from the Brief Pain Inventory was used to measure pain severity. Multinomial logistic regression was used to calculate the odds ratio (OR) of ambulation distance using 1000 ft or more as the reference group.

RESULTS

Persons with SCI who were heavy prescription medication users (defined as weekly or daily use for pain or spasticity) were more likely to be limited to distances less than 150 (OR, 2.82; 95% confidence interval [CI], 1.57-5.04) and 150 to 999 ft (OR, 2.52; 95% CI, 1.45-4.39).

CONCLUSION

Heavy prescription medication use for pain and spasticity was related inversely to a person's ability to achieve community ambulation distances of 1000 ft or more.

Comparing quantification of pain severity by verbal rating and numeric rating scales

BACKGROUND

Researchers have reported widely varying correlations among the 3 main instruments used to quantify pain severity, Visual Analog Scale (VAS), Verbal Rating Scale (VRS), and Numeric Rating Scale (NRS), both at the level of groups and at the level of individuals.

OBJECTIVE

To assess the comparability of reports of pain severity using a VRS and a NRS in a spinal cord injury (SCI) sample.

METHODS

Data were taken from a longitudinal observational study. Patients were 168 individuals with new traumatic SCI admitted for inpatient rehabilitation who completed the VRS and NRS multiple times, each time for multiple pains as appropriate.

RESULTS

For 1114 ratings of pain, VRS and corresponding NRS ratings were correlated weakly (Spearman correlation, rho = 0.38). For 36 individuals with at least 10 completions of paired VRS and NRS, rho ranged from -0.55 to 0.76. Variation in NRS rating for each VRS adjective was reduced by about 25% when between-patient variation was eliminated. Mean NRS ratings by VRS adjective, for patients who had used each of at least 2 adjectives at least 5 times each, showed large differences in mean NRS scores between individuals using the same VRS adjective.

CONCLUSION

There are considerable differences between individuals in how NRS and VRS are used; there also seem to be individuals whose understanding of the meaning of the VRS adjectives is completely different from what was assumed by the creators of this VRS. Both VRS and NRS data must be used with extreme caution by SCI clinicians and researchers.

What are the risk factors of occurence and chronicity of neuropathic pain in spinal cord injury patients?

OBJECTIVE

Analyze the epidemiological data on neuropathic pain in spinal cord injury patients and determine the risk factors for its occurrence and chronicity.

METHOD

Review and analysis of the literature.

RESULTS

Epidemiological data report that 40% of spinal cord injury (SCI) patients suffer from neuropathic pain and 40% of these patients report an intense neuropathic pain. Some factors do not seem to be predictive for the onset of neuropathic pain: the level of injury, complete or incomplete injury, the existence of an initial surgery, sex. However, old age at the time of injury, bullet injury as the cause of trauma, early onset of pain in the weeks following the injury, their initial nature, intensity and continuous pain, as well as associated symptoms all appear to be negative prognostic factors.

CONCLUSION

Neuropathic pain in SCI patients is a major issue, its determining factors still need to be evaluated properly by refining the epidemiological data.

L1 cell adhesion molecule is essential for the maintenance of hyperalgesia after spinal cord injury

Spinal cord injury (SCI) results in a loss of normal motor and sensory function, leading to severe disability and reduced quality of life. A large proportion of individuals with SCI also suffer from neuropathic pain symptoms. The causes of abnormal pain sensations are not well understood, but can include aberrant sprouting and reorganization of injured or spared sensory afferent fibers. L1 is a cell adhesion molecule that contributes to axonal outgrowth, guidance and fasciculation in development as well as synapse formation and plasticity throughout life. In the present study, we used L1 knockout (KO) mice to determine whether this adhesion molecule contributes to sensory dysfunction after SCI. Both wild-type (WT) and KO mice developed heat hyperalgesia following contusion injury, but the KO mice recovered normal response latencies beginning at 4 weeks post-injury. Histological analyses confirmed increased sprouting of sensory fibers containing calcitonin-gene related peptide (CGRP) in the deep dorsal horn of the lumbar spinal cord and increased numbers of interneurons expressing protein kinase C gamma (PKCgamma) in WT mice 6 weeks after injury. In contrast, L1 KO mice had less CGRP(+) fiber sprouting, but even greater numbers of PKCgamma(+) interneurons at the 6 week time point. These data demonstrate that L1 plays a role in maintenance of thermal hyperalgesia after SCI in mice, and implicate CGRP(+) fiber sprouting and the upregulation of PKCgamma expression as potential contributors to this response.