Anthony Chiodo

Central Nervous System Reorganization in a Variety of Chronic Pain States: A Review

Chronic pain can develop from numerous conditions and is one of the most widespread and disabling health problems today. Unfortunately, the pathophysiology of chronic pain in most of these conditions, along with consistently effective treatments, remain elusive. However, recent advances in neuroimaging and neurophysiology are rapidly expanding our understanding of these pain syndromes. It is now clear that substantial functional and structural changes, or plasticity, in the central nervous system (CNS) are associated with many chronic pain syndromes. A group of cortical and subcortical brain regions, often referred to as the “pain matrix,” often show abnormalities on functional imaging studies in persons with chronic pain, even with different pain locations and etiologies. Changes in the motor and sensory homunculus also are seen. Some of these CNS changes return to a normal state with resolution of the pain. It is hoped that this knowledge will lead to more effective treatments or even new preventative measures. The purpose of this article is to review recent advances in the understanding of the CNS changes associated with chronic pain in a number of clinical entities encountered in the field of physical medicine and rehabilitation. These clinical entities include nonspecific low back pain, fibromyalgia, complex regional pain syndrome, postamputation phantom pain, and chronic pain after spinal cord injury.

Electromyographic and Magnetic Resonance Imaging to Predict Lumbar Stenosis, Low-Back Pain, and No Back Symptoms

BACKGROUND Magnetic resonance imaging is commonly used to diagnose lumbar spinal stenosis. Some persons without symptoms have a small lumbar spinal canal. Electrodiagnosis has been used to diagnose spinal stenosis for over sixty years, but we are aware of no masked, controlled trials of the use of electrodiagnosis for that purpose. This study was performed to evaluate the relationships of magnetic resonance imaging measures and electrodiagnostic data with the clinical syndrome of spinal stenosis. METHODS One hundred and fifty persons between the ages of fifty-five and eighty years old, including asymptomatic volunteers and persons referred for lumbar magnetic resonance imaging, underwent clinical examination, electrodiagnosis, and magnetic resonance imaging. Subjects were excluded if they had neuromuscular disease, sacral cancer, or inadequate test results, which left 126 subjects for the final analysis. The final cohort was divided into three groups--no back pain, mechanical back pain, and clinical spinal stenosis--on the basis of the impression of the examining physician, for whom the results of the magnetic resonance imaging and electrodiagnostic testing were masked. A spine surgeon also reviewed both the imaging and clinical examination data. RESULTS The examining physicians diagnosis of clinical spinal stenosis was significantly related to the neurological findings on examination (p < 0.05) and to the spine surgeons diagnosis (p < 0.001). The diagnosis of clinical spinal stenosis was also significantly related to the presence of fibrillations on electrodiagnostic testing (p < or = 0.003), the minimum anteroposterior diameter of the spinal canal on the magnetic resonance images (p = 0.016), and the average of the two smallest spinal canal diameters (p = 0.008) on the images. Measurements on magnetic resonance imaging did not differentiate subjects with clinical spinal stenosis from controls better than chance, whereas paraspinal mapping electrodiagnosis scores did. CONCLUSIONS This prospective, controlled, masked study of electrodiagnosis and magnetic resonance imaging for older subjects showed that imaging does not differentiate symptomatic from asymptomatic persons, whereas electrodiagnosis does. We believe that radiographic findings alone are insufficient to justify treatment for spinal stenosis.

The sensitivity and specificity of electrodiagnostic testing for the clinical syndrome of lumbar spinal stenosis

Study Design. Prospective, masked, double controlled diagnostic trial. Objectives. To determine the sensitivity and specificity of electrodiagnostic consultation (EDX) for the clinical syndrome of lumbar spinal stenosis. Summary of Background Data. EDX has been used for more than 50 years to diagnose spinal disorders but has not met the new standards of evidence-based medicine. Methods. A total of 150 subjects (asymptomatic volunteers and patients with MRIs suggesting back pain or spinal stenosis; 55–80 years of age) underwent physiatrist history and physical examination, MRI, and review of this data by a neurosurgeon, with each clinician masked to any outside information, leading to a unanimous consensus on diagnosis in 55. After masked EDX testing, 7 subjects with undiagnosed neuromuscular disease were discovered. EDX findings were related to “clinical gold standard” diagnoses in 48 persons. Results. Paraspinal mapping EMG score of >4 had 100% specificity and 30% sensitivity for stenosis compared with either the back pain or asymptomatic groups (each, P < 0.04). A composite limb and paraspinal fibrillation score had a sensitivity of 47.8% and specificity of 87.5% (P = 0.008), and H-wave sensitivity was 36.4, specificity 91.3 (P = 0.026) for stenosis versus all controls. Conclusions. This first masked study in the 60-year history of needle electromyography also introduces anatomically validated needle placement, quantified and reproducible examination of the paraspinal muscles, and dual control populations to EDX research in spinal disorders. EDX has statistically significant, clinically meaningful specificity for spinal stenosis and detects neuromuscular diseases that may masquerade as stenosis.

Assessment of a holistic wellness program for persons with spinal cord injury

Zemper ED, Tate DG, Roller S, Forchheimer M, Chiodo A, Nelson VS, Scelza W: Assessment of a holistic wellness program for persons with spinal cord injury. Am J Phys Med Rehabil 2003;82:957–968. ObjectiveTo test the effectiveness of a holistic (comprehensive and integrated) wellness program for adults with spinal cord injury. DesignA total of 43 adults with spinal cord injury were randomly assigned to intervention or control groups. The intervention group attended six half-day wellness workshops during 3 mos, covering physical activity, nutrition, lifestyle management, and prevention of secondary conditions. Outcome measures included several physical measures and standard psychosocial measures. Statistical analyses included paired t tests, used to determine within-group differences, and multiple regression conducted to assess between-group differences. ResultsWhen comparing within-group baseline and final results, the intervention group reported fewer and less severe secondary conditions by the end of the study. Similarly, significant improvements were found in health-related self-efficacy and health behaviors. No significant changes in physiologic variables were observed. Although no significant between-group differences were observed, regression analyses suggested participation in the wellness program may be associated with improved health behaviors. ConclusionWithin-group comparisons suggest improvements in several areas of the participants’ overall health behaviors. These findings, although preliminary, emphasize the potential role of health behaviors in positively influencing long-term health outcomes and quality of life.

Predictors of pain and function in persons with spinal stenosis, low back pain, and no back pain.

Study Design. Longitudinal masked, double-controlled cohort study. Objectives. To determine prognosis and predictors of function and pain in persons with spinal stenosis. Summary of Background Data. The clinical syndrome of spinal stenosis is common and disabling, but not clearly related to anatomic measures. Prognosis not well studied. Methods. Persons 55 to 80 years of age with and without stenosis on preliminary review of magnetic resonance imaging (MRI), and asymptomatic volunteers underwent screening, questionnaires, physical examination, ambulation testing, masked electromyogram (EMG), and masked MRI scans; these were repeated at >18 months. Results. Twenty-three asymptomatic, 28 back pain, and 32 clinically diagnosed stenosis subjects underwent follow-up. Although initial and follow-up diagnosis tended to agree (kappa = 0.394, P < 001), there were substantial shifts between the three groups. Among persons with clinically diagnosed stenosis, every measure trended for improvement, including significant changes in pain, ambulation, and EMG. Ambulation velocity and Pain Disability Index at follow-up were predicted by initial disability measures. Pain was predicted by initial sleep difficulty but not initial pain. EMG and MRI did not predict function or pain. Conclusion. Clinically recognized spinal stenosis is fluctuating and largely improving, and in continuum with back pain and no symptoms. Since anatomic and neurologic deficits do not predict future function, they should not be weighed heavily in surgical risk-benefit discussions.

Relationship of spasticity to soft tissue body composition and the metabolic profile in persons with chronic motor complete spinal cord injury.

Abstract Background/Objective: To determine the effects of spasticity on anthropometrics, body composition (fat mass [FM] and fat-free mass [FFM]), and metabolic profile (energy expenditure, plasma glucose, insulin concentration, and lipid panel) in individuals with motor complete spinal cord injury (SCI). Methods: Ten individuals with chronic motor complete SCI (age, 33 ± 7 years; BMI, 24 ± 4 kg/m2; level of injury, C6—T11; American Spinal Injury Association A and B) underwent waist and abdominal circumferences to measure trunk adiposity. After the first visit, the participants were admitted to the general clinical research center for body composition (FFM and FM) assessment using dual energy x-ray absorptiometry. After overnight fasting, resting metabolic rate (RMR) and metabolic profile (plasma glucose, insulin, and lipid profile) were measured. Spasticity of the hip, knee, and ankle flexors and extensors was measured at 6 time points over 24 hours using the Modified Ashworth Scale. Results: Knee extensor spasticity was negatively correlated to abdominal circumferences (r = -0.66, P = 0.038). After accounting for leg or total FFM, spasticity was negatively related to abdominal circumference (r = -0.67, P = 0.03). Knee extensor spasticity was associated with greater total %FFM (r = 0.64; P = 0.048), lower %FM (r = -0.66; P = 0.03), and lower FM to FFM ratio. Increased FFM (kg) was associated with higher RMR (r = 0.89; P = 0.0001). Finally, spasticity may indirectly influence glucose homeostasis and lipid profile by maintaining FFM (r = -0.5 to -0.8, P < 0.001). Conclusion: Significant relationships were noted between spasticity and variables of body composition and metabolic profile in persons with chronic motor complete SCI, suggesting that spasticity may play a role in the defense against deterioration in these variables years after injury. The exact mechanism is yet to be determined.

Accuracy of intermittent fluoroscopy to detect intravascular injection during transforaminal epidural injections

Study Design. Prospective validity study. Objective. To determine how accurately intermittent fluoroscopy detects inadvertent intravascular injection during transforaminal epidurals. Summary of Background Data. Serious morbidity caused by transforaminal epidural injections is frequently related to inadvertent vascular injection of corticosteroids. Several methods have been proposed to reduce the risk of vascular injection, but none have demonstrated efficacy. Because of the fleeting appearance of vascular contrast patterns, live fluoroscopy is recommended during contrast injection. Despite this, many practitioners continue to use intermittent fluoroscopy. Methods. During 50 epidural injections dynamic contrast flow was observed under live fluoroscopy, and the “dynamic true” image was determined. Two intermittent fluoroscopy images were saved from each injection, the first just before completing the contrast injection (“static C” image), and another 1 second after the contrast injection ceased (“static PC” image). Five physicians with experience performing these injections independently interpreted the 100 randomly ordered static images. Accuracy of intermittent fluoroscopy was determined by comparing the interpretation of the 100 static images with the dynamic true patterns observed under live fluoroscopy. Results. Overall, interpretation of the static images missed 57% of the vascular injections. Timing of the static images influenced accuracy with the static C images missing 50% of vascular injections, and the static PC images missing 68% of vascular injections (P = 0.075). Accuracy was significantly worse when vascular injections occurred simultaneous to the expected epidural injection (P = 0.041), and in lumbar images (P = 0.012). Conclusion. Based on these findings, we recommend use of live fluoroscopy to observe dynamic contrast flow during transforaminal epidural steroid injections.

Secondary health conditions in individuals aging with SCI: Terminology, concepts and analytic approaches

Study design:Literature review.Objectives:Utilizing individuals with spinal cord injury (SCI) as a representative population for physical disability, this paper: (1) reviews the history of the concept of secondary conditions as it applies to the health of individuals aging with long-term disabilities; (2) proposes a definition of secondary health conditions (SHCs) and a conceptual model for understanding the factors that are related to SHCs as individuals age with a disability; and (3) discusses the implications of the model for the assessment of SHCs and for developing interventions that minimize their frequency, severity and negative effects on the quality of life of individuals aging with SCI and other disabilities.Methods:Key findings from research articles, reviews and book chapters addressing the concept of SHCs in individuals with SCI and other disabilities were summarized to inform the development of a conceptual approach for measuring SCI-related SHCs.Conclusions:Terms used to describe health conditions secondary to SCI and other physical disabilities are used inconsistently throughout the literature. This inconsistency represents a barrier to improvement, measurement and for the development of effective interventions to reduce or prevent these health conditions and mitigate their effects on participation and quality of life. A working definition of the term SHCs is proposed for use in research with individuals aging with SCI, with the goal of facilitating stronger evidence and increased knowledge upon which policy and practice can improve the health and well-being of individuals aging with a disability.

Medical rehabilitation in Ghana.

Purpose. To explore the current system of medical rehabilitation services for persons with disabilities in a developing country (Ghana) and to identify future needs, opportunities, and barriers. Methods. Information was obtained through a literature review and through interviews with healthcare providers, disabled peoples organizations, educators, government officials, and consumers. Direct observations were made of Ghanas capital city, Accra, and of a major tertiary medical center there, Korle Bu Teaching Hospital. Results. Ghana has virtually no medical rehabilitation and few laws to protect the disabled. There are no occupational therapists or physiatrists in the entire country, and only a handful of physical therapists, prosthetists, orthotists, and speech therapists. There are many barriers to the establishment of such services, including lack of funding, limited government support, cultural stigma of the disabled and poor utilization of existing resources. Conclusions. A national model for sustainable medical rehabilitation is needed in Ghana and likely in other similar countries.

Cut Point Determination in the Measurement of Pain and Its Relationship to Psychosocial and Functional Measures After Traumatic Spinal Cord Injury: A Retrospective Model Spinal Cord Injury System Analysis

OBJECTIVE To evaluate potential pain cutoff scores reflecting mild, moderate, and severe pain in the spinal cord injury (SCI) population and determine the relationship between the derived cutoff scores and both psychosocial and functional outcome measures. DESIGN Retrospective analysis. SETTING SCI Model Systems. PARTICIPANTS Persons (N=6096; age >18y) with traumatic SCI (American Spinal Injury Association Impairment Scale [AIS] grades A-D; injured in 1973-2008). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Numeric rating scale (NRS) of pain severity (11 points), NRS of pain interference (5 points), Satisfaction With Life Scale, Patient Health Questionnaire-9, Craig Handicap Assessment and Reporting Technique Short-Form (CHART-SF), motor component of the FIM (M-FIM), and employment. RESULTS The best set of pain severity cutoff points are 1 to 3, 4 to 6, and 7 to 10. This was validated by randomly assigning sample members to 2 groups and replicating. There were significant differences in all outcomes as a function of pain severity grouping, although they explained little of the variance in M-FIM and CHART-SF Physical Independence scale scores. Neurologic status differed significantly between pain groups, with incongruence between pain severity and interference in people in the AIS grade D group, who reported the greatest pain interference and least pain severity. CONCLUSION Pain severity can be categorized into groups that reflect pain interference. These groupings differentiate psychosocial well-being better than activity limitations. They do not provide a comprehensive pain assessment, for which pain type, location, and interference are likely to be necessary.