Thomas Cheriyan

Spinal cord injury models: a review

Background:Animal spinal cord injury (SCI) models have proved invaluable in better understanding the mechanisms involved in traumatic SCI and evaluating the effectiveness of experimental therapeutic interventions. Over the past 25 years, substantial gains have been made in developing consistent, reproducible and reliable animal SCI models.Study design:Review.Objective:The objective of this review was to consolidate current knowledge on SCI models and introduce newer paradigms that are currently being developed.Results:SCI models are categorized based on the mechanism of injury into contusion, compression, distraction, dislocation, transection or chemical models. Contusion devices inflict a transient, acute injury to the spinal cord using a weight-drop technique, electromagnetic impactor or air pressure. Compression devices compress the cord at specific force and duration to cause SCI. Distraction SCI devices inflict graded injury by controlled stretching of the cord. Mechanical displacement of the vertebrae is utilized to produce dislocation-type SCI. Surgical transection of the cord, partial or complete, is particularly useful in regenerative medicine. Finally, chemically induced SCI replicates select components of the secondary injury cascade. Although rodents remain the most commonly used species and are best suited for preliminary SCI studies, large animal and nonhuman primate experiments better approximate human SCI.Conclusion:All SCI models aim to replicate SCI in humans as closely as possible. Given the recent improvements in commonly used models and development of newer paradigms, much progress is anticipated in the coming years.

Efficacy of tranexamic acid on surgical bleeding in spine surgery: a meta-analysis.

BACKGROUND CONTEXT Spine surgery is usually associated with large amount of blood loss, necessitating blood transfusions. Blood loss-associated morbidity can be because of direct risks, such as hypotension and organ damage, or as a result of blood transfusions. The antifibrinolytic, tranexamic acid (TXA), is a lysine analog that inhibits activation of plasminogen and has shown to be beneficial in reducing surgical blood loss. PURPOSE To consolidate the findings of randomized controlled trials (RCTs) investigating the use of TXA on surgical bleeding in spine surgery. STUDY DESIGN A metaanalysis. STUDY SAMPLE Randomized controlled trials investigating the effectiveness of intravenous TXA in reducing blood loss in spine surgery, compared with a placebo/no treatment group. METHODS MEDLINE, Embase, Cochrane controlled trials register, and Google Scholar were used to identify RCTs published before January 2014 that examined the effectiveness of intravenous TXA on reduction of blood loss and blood transfusions, compared with a placebo/no treatment group in spine surgery. Metaanalysis was performed using RevMan 5. Weighted mean difference with 95% confidence intervals was used to summarize the findings across the trials for continuous outcomes. Dichotomous data were expressed as risk ratios with 95% confidence intervals. A p<.05 was considered statistically significant. RESULTS Eleven RCTs were included for TXA (644 total patients). Tranexamic acid reduced intraoperative, postoperative, and total blood loss by an average of 219 mL ([-322, -116], p<.05), 119 mL ([-141, -98], p<.05), and 202 mL ([-299, -105], p<.05), respectively. Tranexamic acid led to a reduction in proportion of patients who received a blood transfusion (risk ratio 0.67 [0.54, 0.83], p<.05) relative to placebo. There was one myocardial infarction (MI) in the TXA group and one deep vein thrombosis (DVT) in placebo. CONCLUSIONS Tranexamic acid reduces surgical bleeding and transfusion requirements in patients undergoing spine surgery. Tranexamic acid does not appear to be associated with an increased incidence of pulmonary embolism, DVT, or MI.

Ninety-day readmissions after degenerative cervical spine surgery: A single-center administrative database study

Background Unplanned hospital readmissions result in significant clinical and financial burdens to patients and the healthcare system. Readmission rates and causes have been investigated using large administrative databases which have certain limitations in data reporting and coding. The objective of this study was to provide a description of 90 day post-discharge readmissions following surgery for common degenerative cervical spine pathologies at a large-volume tertiary hospital. The study also compared the readmission rates of patients who underwent anterior- and posterior-approach procedures. Methods The administrative records from a single-center, high-volume tertiary institution were queried using ICD-9 codes for common cervical pathology over a three year period to determine the rate and causes of readmissions within the 90 days following the index surgery. Results A total of 768 patients underwent degenerative cervical spine surgery during the three year study period. Within 90 days of discharge, 24 (3.13%) patients were readmitted; 16 (2.06%) readmissions were planned for lumbar surgery; 8 (1.04%) readmissions were unplanned. 640 patients underwent procedures involving an anterior approach and 128 patients underwent procedures involving a posterior approach. There were 14 (2.17%) planned readmissions in the anterior group and 2 (1.5%) in the posterior group. The unplanned readmission rate was 0.63% (4 patients) and 3.13% (4 patients) in the anterior and posterior groups, respectively. (p=0.0343). Conclusion The 90 day post-discharge unplanned readmission rate that followed elective degenerative cervical spine surgery was 1.04%. The unplanned readmission rate associated with posterior-approach procedures (3.13%) was significantly higher than that of anterior-approach procedures (0.63%). Level of evidence: IV

Spinal disorders and treatments : the NYU-HJD comprehensive textbook

Part I. Basic Science and Spinal Assessment * Basic Science of the Degenerative Spine * Biomechanics of the Spine: Clinical Relevance * Balance posture and stability in Spine Disorders * Differential Diagnosis of Cervical & Lumbar Spine Disorders * Neurological Diagnoses that Mimic Spinal Disorders * Examination & Evaluation of Neck Pain * Examination & Evaluation of Lower Back Pain * Examination & Evaluation of Radiculopathy * Evaluation of Adolescent Scoliosis * Evaluation of Adult Scoliosis * Measurement of the Scoliosis Curve * Assessment of Disability * Non-MRI Imaging Evaluation of Cervical & Lumbar Spine: Utilizaton of X-Rays, CT Scan, Nucular Medicine and Ultrasound? * MRI Evaluation of Cervical & Lumbar Spine Disorders: What to look for * Interventional Diagnostic Procedures: Nerve Blocks & Discography * Rheumatic disease and Myofascial pain * Diagnosis of Osteopenia & Osteoporosis Part II. Non- Invasive Therapeutic Intervention * Therapeutic Approach to Spinal Disorders * Pharmacological Management of Spinal Pain: Narcotic * Pharmacological Management of Spinal Pain: Non-Narcotic * Preventing Addition & Management of the Addicted Patient * Pharmacological Management of Osteoporosis * Non-operative Treatment of Cervical Myelopathy & Radiculopathy * Alternative Medicine Treatment in Spinal Disorders: Application of Science to the Art * Psychosocial Management of the Patient with Chronic Lower Back Pain * Conservative approach to triage of patients with spinal pain Part III. Spinal Injection * Introduction to Spinal Injections * Diagnostic & Therapeutic Value of Spinal Injections * Trigger Point Injections * Sacroiliac Injections * Peripheral Joint Injections * Sympathetic Blocks * Epidural Steroid Injections * Intra-articular Facet Injections Including Facet Cyst Injections * Complication of Spinal Injections * Median Branch Blocks & Rhizotomy * IDET, Nucleoplasty, Biacuplasty: Are These Valid Treatment Options?? * Indications & Efficacy of Spinal Cord Stimulators in Axial Low Back Pain Part IV. Surgical Management * Introduction to Surgical Management of Spinal Disorders * Surgical Treatment of Degenerative Spondylolisthesis: Decompression, Fusion or Both * Surgical Decision Making in Differentiating Cervical Radiculopathy from Upper Extremity Peripheral Nerve Compression * Cervical Disc Herniations: Is the Anterior or Posterior Approach make a Difference in Outcome * Surgical Treatment of Cervical Stenosis * Operative Treatment of Cervical Spondylosis & OPLL * Motion Preservation Surgery * Minimally Invasive Surgery * Cervical Total Disc Replacement * Lumbar Total Disc Replacement Surgery * Conventional, Microscopic, Endoscopic Surgical Treatment Of Lumbar Disc Herniations * Surgical Treatment of lumbar stenosis * Overview of Spine Deformity Surgery * Operative management of Pediatric Deformity * Surgical Treatment of Adult Degenerative Deformities * Surgical Interventions in Osteoporosis & the Compression Fracture * Surgical Management of the Rheumatoid Spine * Traumatic Cervical Spinal Fracture Surgery * Lumbar Traumatic Spinal Fracture Surgery * Tumors of The Spine * Intraoperative Monitoring in Spine Surgery