Citations

Background The reported prevalence of chronic pain after spinal cord injury (SCI) varies widely due, in part, to differences in the taxonomy of chronic pain. A widely used classification system is available to describe subcategories of chronic pain in SCI, but the prevalence of chronic pain in SCI based on this system is unknown. Objective The primary objective of this systematic review and meta-analysis is to determine the prevalence of chronic pain after SCI based on the International Spinal Cord Injury Pain (ISCIP) classification system. Evidence review A comprehensive search of databases from January 1980 to August 2019 was conducted. The risk of bias was assessed using a modified tool developed for uncontrolled studies. The Grading of Recommendations, Assessment, Development and Evaluation approach was used to assess certainty in prevalence estimates. Findings A total of 1305 records were screened, and 37 studies met inclusion criteria. The pooled prevalence of overall chronic pain was 68% (95% CI 63% to 73%). The pooled prevalence of neuropathic pain in 13 studies was 58% (95% CI 49% to 68%); the pooled prevalence of musculoskeletal pain in 11 studies was 56% (95% CI 41% to 70%); the pooled prevalence of visceral pain in 8 studies was 20% (95% CI 11% to 29%) and the pooled prevalence of nociceptive pain in 2 studies was 45% (95% CI 13% to 78%). Meta-regression of risk of bias (p=0.20), traumatic versus non-traumatic etiology of injury (p=0.59), and studies where pain was a primary outcome (p=0.32) demonstrated that these factors were not significant moderators of heterogeneity. Certainty in prevalence estimates was judged to be low due to unexplained heterogeneity. Conclusion This systematic review and meta-analysis extends the findings of previous studies by reporting the prevalence of chronic pain after SCI based on the ISCIP classification system, thereby reducing clinical heterogeneity in the reporting of pain prevalence related to SCI.

Abstract Background The Seattle Angina Questionnaire (SAQ) is a self-administered questionnaire used in cardiac patients to quantify angina based on five scales: physical limitation scale, anginal stability scale, anginal frequency scale, treatment satisfaction scale, and the disease perception scale. Here we report the use of the SAQ to assess angina symptoms in 18 patients who underwent spinal cord stimulation (SCS) for refractory angina pectoris (RAP) at the Mayo Clinic. Methods Electronic health records were searched to find patients who underwent SCS for the treatment of RAP at a single institution from 2003 to 2018. Eligible patients were asked to participate in a phone survey that included the SAQ. Results Out of 13 patients who still had their implant, six (46%) had minimal physical limitations. Ten patients (76.9%) had favorable anginal frequency scores, defined as minimal or mild. Out of the five patients who had their device removed, one (20%) had minimal physical limitations and three (60%) had favorable anginal frequency scores. There was a high treatment satisfaction score for both those with their implant in place and those with the device removed. Conclusion The SAQ is useful as a comprehensive measure specific to patients with RAP assessing function, pain, and satisfaction. The utilization of this tool pre- and post-operatively may provide additional information to analyze the effectiveness of SCS for RAP.

AbstractTotal knee arthroplasty is a common and successful treatment modality for knee arthritis that is refractory to conservative management strategies. Over 600,000 arthroplasties are performed per year in the United States, and this number is expected to increase in the coming years. Unfortunately, 8% to 34% of patients experience chronic pain after having a total knee arthroplasty. These patients should undergo an appropriate work‐up by the orthopedic surgeon, but many times a surgical problem is not uncovered. In these situations, a thorough and specific plan for pain management should be sought. In this article, we outline the work‐up of a painful total knee arthroplasty. Then we provide a thorough review of interventional pain management strategies and highlight the pertinent literature. Lastly, we hypothesize future developments in the field that may provide better outcomes for patients suffering from painful total knee arthroplasty.

Abstract Background/Objective Chronic pain is commonly reported in individuals with spinal cord injuries (SCIs), with recent prevalence reported as high as 80%. Uncontrolled pain is known to decrease quality of life, attenuate mood, and impact sleep. Spinal cord stimulation (SCS) for the treatment of refractory pain was first used in the SCI population in 1972. To date there have been no randomized controlled trials examining the effect of SCS on neuropathic pain post‐SCI. A literature review in 2009 identified 27 studies, the majority prior to 2000, that included at least 1 patient with SCI. Given the significant advancements in the field of SCS, this review examines the updated evidence of SCS for the treatment of neuropathic pain in individuals with SCI and provides guidance on future investigations. Methods MEDLINE and EMBASE databases were searched. All published reports, case series, and clinical trials reviewing SCS for neuropathic pain that included at least 1 individual with SCI were included. Results The initial search identified 376 reports, of which 22 met inclusion criteria, for a total of 69 patients. All reports were of very low quality. A majority of the reported patients were male, underwent tonic stimulation, and reportedly experienced improvement in pain and spasticity, with decreased use of pain medication. Conclusions The synthesized findings from primarily case studies support the safety of SCS in SCI with the suggestion of potential pain relief benefit; however, data from low‐quality studies are insufficient for informing clinical practice. A well‐designed, prospective clinical trial is proposed to further investigate this indication.

ObjectiveTo assess the biologic effects of lidocaine on the viability, proliferation, and function of human adipose tissue–derived mesenchymal stromal/stem cells (MSCs) in vitro.MethodsAdipose‐derived MSCs from three donors were exposed to lidocaine at various dilutions (2 mg/mL to 8 mg/mL) and exposure times (0.5 to 4 hours). Cell number and viability, mitochondrial activity, and real‐time reverse‐transcriptase quantitative polymerase chain reaction (RT‐qPCR) were analyzed at 0 (immediate effects) or 24 and 48 hours (recovery effects) after treatment with lidocaine.ResultsTrypan blue staining showed that increasing concentrations of lidocaine decreased the number of observable viable cells. 3‐[4,5,dimethylthiazol‐2‐yl]‐5‐[3‐carboxymethoxy‐phenyl]‐2‐[4‐sulfophenyl]‐2H‐tetrazolium (MTS) assays revealed a concentration‐ and time‐ dependent decline of mitochondrial activity and proliferative ability. Gene expression analysis by RT‐qPCR revealed that adipose‐derived MSCs exposed to lidocaine express robust levels of stress response/cytoprotective genes. However, higher concentrations of lidocaine caused a significant downregulation of these genes. No significant differences were observed in expression of extracellular matrix (ECM) markers COL1A1 and DCN except for COL3A1 (P < .05). Levels of messenger RNA (mRNA) for proliferation markers (CCNB2, HIST2H4A, P < .001) and MKI67 (P < .001) increased at 24 and 48 hours. Expression levels of several transcription factors— including SP1, PRRX1, and ATF1—were modulated in the same manner. MSC surface markers CD44 and CD105 demonstrated decreased expression immediately after treatment, but at 24 and 48 hours postexposure, the MSC markers showed no significant difference among groups.ConclusionLidocaine is toxic to MSCs in a dose‐ and time‐ dependent manner. MSC exposure to high (4‐8 mg/mL) concentrations of lidocaine for prolonged periods can affect their biologic functions. Although the exposure time in vivo is short, it is essential to choose safe concentrations when applying lidocaine along with MSCs to avoid compromising the viability and potency of the stem cell therapy.

Abstract Background The use of mesenchymal stem cells (MSCs) in clinical applications for the treatment of musculoskeletal disease is steadily increasing in office-based practice. The so-called “first generation” of MSCs is defined as autologous stem cells that have undergone minimal manipulation and are used for a homologous purpose. Systematic reviews of the clinical trials completed to date of such MSCs enable practitioners to better understand what is currently known about the outcomes and side effects of such treatments. Study Design A systematic review of human clinical studies of office-based MSC therapy for the treatment of painful degenerative musculoskeletal conditions. Methods A search of the Ovid MEDLINE, EMBASE, and Scopus databases was conducted from 2006 through September 2016. Seven hundred sixty-one records were identified from database searching, and two records from reference review of included papers. Studies with human subjects that evaluated treatment of musculoskeletal disease with minimally manipulated MSCs were included. Results Eight studies were included in this review based on selection criteria. A total of 941 patients were included, 841 of whom received cellular products, and no significant adverse events were reported. Symptomatology generally improved, though no differences were seen over controls where present. Conclusion Support in the literature is strongest for the use of bone marrow aspirate concentrate (BMAC) injections for the treatment of knee pain, but applications of the use of BMAC and peripheral blood–derived MSCs for the treatment of hip pain, tendon pain, and disc pain have all been reported. Further research is required, with large randomized controlled trials.