Robert P. Norton
University of Miami
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Journal of Spinal Disorders & Techniques | 2008
Harvey E. Smith; Stewart M. Kerr; Mitchell Maltenfort; Sonia Chaudhry; Robert P. Norton; Todd J. Albert; James S. Harrop; Alan S. Hilibrand; D. Greg Anderson; Branko Kopjar; Darrel S. Brodke; Jeffrey C. Wang; Michael G. Fehlings; Jens R. Chapman; Archit Patel; Paul M. Arnold; Alexander R. Vaccaro
Study Design A retrospective cohort study of operative versus nonoperative treatment of isolated type II odontoid fractures in patients aged 80 years and more without neurologic deficit admitted to a level 1 spinal cord injury center between June 1985 and July 2006. Objective To assess the presentation and acute complications of operatively and nonoperatively managed type II odontoid fractures in the octogenarian population. Summary of Background Data Type II odontoid fractures are the most common cervical spine fracture in the elderly. Studies suggest acute in-hospital complication rates in type II odontoid fractures in the elderly exceed 50%. Few studies have examined the acute in-hospital outcomes of isolated type II odontoid fractures in the octogenarian population. Methods The medical records of 223 consecutive C2 fractures from June 1985 to July 2006 over the age of 80 years were reviewed retrospectively. Patients with associated cervical spine fractures were excluded. Eighty neurologically intact patients over age 80 were identified with isolated acute type II odontoid fractures. The charts were reviewed and mechanism of injury, comorbidities, date of injury, date of admission, date of discharge, radiology reports, discharge disposition, associated injuries, fracture management, type of surgical fixation (if any), and documented complications were abstracted. Results Thirty-two patients received operative treatment (10 anterior and 22 posterior) and 40 patients received nonsurgical treatment. Eight patients were excluded because the medical record could not be located. The mean age was 85.5±3.5 years in the surgical and 87.3±4.7 years in the nonsurgical group (P>0.05); mean length of acute hospital stay was 11.2±8.5 days in the nonsurgical and 22.8±28.3 days in the surgical group (P<0.05); mean comorbidity score was 2.3±1.2 in the nonsurgical and 2.0±1.0 in the surgical group (P>0.5); mean fracture displacement was 4.1±3.5 mm in the nonsurgical and 3.9±3.4 mm in the surgical group (P>0.5). Acute in-hospital mortality rate was 15% in the nonsurgical group and 12.5% in the surgical group (P>0.05). The percentage of patients experiencing at least one significant complication was higher in the operative group than the nonoperative group (62% vs. 35%, respectively, P<0.05). Conclusions Type II odontoid fractures in the octogenarian population are associated with substantial morbidity and mortality, irrespective of management method. Prospective studies are needed to better elucidate management strategies for this difficult clinical problem.
Journal of Spinal Disorders & Techniques | 2007
Mark F. Kurd; Deepan Patel; Robert P. Norton; George Picetti; Brian Friel; Alexander R. Vaccaro
Summary of Background Data Symptomatic spondylolysis resulting from a stress fracture of the pars interarticularis is a cause of low back pain in the juvenile and adolescent patient. Treatment is conservative in the majority of cases. Objective To analyze the outcome of patients with symptomatic isthmic spondylolysis treated nonoperatively with a custom fit thoracolumbar orthosis and activity cessation for 3 months followed by an organized physical therapy program. Study Design Retrospective case series. Patient Sample Four hundred thirty-six juvenile and adolescent patients with spondylolysis. Outcome Measures Pain improvement, hamstring flexibility, range of motion, resolution of back spasms, and return to previous activities. Methods Retrospective review of 436 juvenile and adolescent patients with symptomatic spondylolysis confirmed by single-photon emission computed tomography or computed tomography. Clinical outcomes were assessed through patient history and physical examination. Results Ninety-five percent of patients achieved excellent results according to a modified Odoms Criteria. The remaining 5% of patients achieved good results as they required occasional nonsteroidal anti-inflammatory drugs to relieve pain. Back spasms were resolved and hamstring tightness and range of motion returned to normal in all patients. All patients returned to their preinjury activity level. No patients went on to surgery. Conclusions Symptomatic juvenile and adolescent patients with an isthmus spondylolysis may be effectively managed with a custom fit thoracolumbar orthosis brace and activity cessation for approximately 3 months followed by an organized physical therapy program.
Spine | 2007
Robert P. Norton; Deepan Patel; Mark F. Kurd; George Picetti; Alexander R. Vaccaro
Study Design. Retrospective case cohort series. Objective. To analyze the outcomes of thoracoscopy in the surgical treatment of adolescent idiopathic scoliosis. Summary of Background Data. Traditionally, progressive idiopathic scoliosis has been treated surgically with either an open posterior, anterior, or combined surgical approach. Surgical methods are being explored to minimize the extent of soft tissue disruption such as thoracoscopy followed spinal release, bone grafting, and instrumentation. Several authors have reported good results using thoracoscopy in the treatment of spinal deformity following a requisite learning curve. Methods. A consecutive case cohort series of 45 adolescent patients with idiopathic scoliosis evaluated and treated at a single institution. Patients with a progressive deformity underwent a thoracoscopically assisted curve correction, fusion, and instrumentation procedure. After surgery, patients were assessed at 1, 3, 6, and 12 months and then annually. Results. All patients underwent successful thoracoscopic instrumentation and fusion without the need for an open conversion. The average preoperative thoracolumbar Cobb measurement of the major curve was 51.6°. The thoracolumbar levels instrumented anteriorly ranged from T7 to L3 and had an average postoperative Cobb angle of 6.58°, with an overall improvement of 87.3%. To date, at a mean follow up of 4.6 years, all curves have maintained correction. Sagittal balance was recreated or maintained through the application of interbody femoral ring allografts. Operative times averaged 5 hours and 46 minutes, with a range of 3 hours, 48 minutes to 6 hours, 55 minutes. Hospital stays averaged 2.9 days, with a range of 2 to 7 days. All patients were completely off pain medication before their first postoperative visit at 4 weeks. Children were back to school between 2 and 4 weeks on average. There were a total of 3 complications. One patient experienced transient chest wall numbness, which resolved by 3 months. Two patients developed postoperative mucus plugging in the ventilated lung. Conclusion. Endoscopic thoracoscopic spinal deformity correction, fusion, and instrumentation is a safe and feasible method of surgical management of an adolescent patient with progressive scoliosis. The key to successful fusion is a total discectomy and complete endplate removal. This method appears to be comparable to open procedures in terms of curve correction with significantly shorter hospitalization and rehabilitation due to less surgical discomfort. The thoracoscopic correction of adolescent scoliosis warrants continued development and evaluation as a surgical method of scoliosis correction.
Journal of The American Academy of Orthopaedic Surgeons | 2014
Frank J. Eismont; Robert P. Norton; Brandon P. Hirsch
Lumbar degenerative spondylolisthesis (DS) is a common cause of low back pain, radiculopathy, and/or neurogenic claudication. Treatment begins with a trial of nonsurgical methods, including physical therapy, NSAIDs, and epidural corticosteroid injections. Surgical treatment with decompression and fusion is recommended for patients who do not respond to this initial regimen. Although much has been published in the past two decades on the surgical management of DS, the optimal method remains controversial. Interbody fusion may improve arthrodesis rates and can be performed via numerous surgical approaches. Minimally invasive techniques continue to be developed. Particular attention to surgical management of DS in the elderly is warranted given the increasing numbers of elderly persons. Healthcare utilization in the future must take into account evidence-based medicine that establishes clinically effective practices while simultaneously being cost effective.
The Spine Journal | 2014
Robert P. Norton; Edward Milne; David N. Kaimrajh; Frank J. Eismont; Loren L. Latta; Seth K. Williams
BACKGROUND CONTEXT Conventionally, short-segment fusion involves instrumentation of one healthy vertebra above and below the injured vertebra, skipping the injured level. This short-segment construct places less surgical burden on the patient compared with long-segment constructs, but is less stable biomechanically, and thus has resulted in clinical failures. The addition of two screws placed in the fractured vertebral body represents an attempt to improve the construct stiffness without sacrificing the benefits of short-segment fusion. PURPOSE To determine the biomechanical differences between four- and six-screw short-segment constructs for the operative management of an unstable L1 fracture. STUDY DESIGN Biomechanical study of instrumentation in vertebral body cadaveric models simulating an L1 axial load injury pattern. METHODS Thirteen intact spinal segments from T12 to L2 were prepared from fresh-frozen cadaver spines. An axial load fracture of at least 50% vertebral body height was produced at L1 and then instrumented with pedicle screws. Specimens were evaluated in terms of construct stiffness, motion, and rod strain. Two conditions were tested: a four-screw construct with no screws at the L1 fractured body (4S) and a six-screw construct with screws at all levels (6S). The two groups were compared statistically by paired Student t test. RESULTS The mean stiffness in flexion-extension was increased 31% (p<.03) with the addition of the two pedicle screws in L1. Relative motion in terms of vertical and axial rotations was not significantly different between the two groups. The L1-L2 rod strain was significantly increased in the six-screw construct compared with the four-screw construct (p<.001). CONCLUSIONS In a cadaveric L1 axial load fracture model, a six-screw construct with screws in the fractured level is more rigid than a four-screw construct that skips the injured vertebral body.
Evidence-based Spine-care Journal | 2013
Kristina Bianco; Frank J. Schwab; Robert P. Norton; Justin S. Smith; Ibrahim Obeid; Gregory M. Mundis; Khaled M. Kebaish; Richard Hostin; Robert A. Hart; Douglas C. Burton; Christopher P. Ames; Oheneba Boachie-Adjei; Themistocles S. Protopsaltis; Virginie Lafage
Study Type Retrospective review of a prospectively collected multicenter database. Introduction Three-column resection osteotomies (3CO), including pedicle subtraction osteotomies and vertebral column resections are performed for correction of sagittal deformity; however, they have high rates of reported complications. This study examined the incidence and intercenter variability of major intraoperative complications (IOC), postoperative complications (POC), and overall complications (IOC + POC) up to 6 weeks postoperation. Objective The aim of the study is to examine the incidence and intercenter variability of major complications associated with 3CO. Patients and Methods A retrospective review of patients with 3CO from eight different sites was performed. The incidence and types of complications were determined for the study population (N = 423). The analysis compared patients with one (n = 391) and two (n = 32) osteotomies, as well as patients with a thoracic osteotomy (ThO) (n = 72) versus a lumbosacral osteotomy (LSO) (n = 319) of the spine. Subsequent analysis was performed to compare sites with low-osteotomy volumes (< 50 patients) to sites with large osteotomy volumes (more than 50 patients). Major blood loss (MBL) was defined as more than 4L. Results Of the 423 patients, the incidence of major IOC, POC, and overall complications was 28, 45, and 58%, respectively (Table 1). The most common major IOC was MBL (24%) and the most common POC was unplanned return to the operating room (OR) (19%). Other IOC included cord deficit (2.6%), pneumothorax (1.5%), large vessel injury (1.7%), nerve root injury (1.4%), and cardiac arrest (0.2%). Other POC included motor deficit (12.1%), deep infection (7.6%), acute respiratory distress/failure (4.7%), deep venous thrombosis (3.1%), pulmonary embolism (2.8%), arrhythmia (1.2%), reintubation and sepsis (0.7%), cauda equine syndrome, myocardial infarction, visual deficit, stroke (0.5%), and death (0.2%). Patients with one 3CO had significantly less POC (43 vs. 69%, p < 0.01) and overall complications (57 vs. 75%, p < 0.01) than patients with two 3CO (Fig. 1). IOC, MBL, and return to the OR were not significantly different between groups. Patients with ThO had significantly more POC (66 vs. 39%, p < 0.01) and overall complications (76 vs. 53%, p < 0.001) than patients with LSO. Patients with LSO had more MBL (25 vs. 14%, p = 0.04). Patients with ThO had more unplanned return to OR (41 vs. 14%, p < 0.001) (Fig. 2). The incidence of IOC was greater for the low-volume sites than high-volume sites (46 vs. 23%, p < 0.001). Low-volume sites had a higher frequency of patients with MBL than high-volume sites (45 vs. 18%, p < 0.001) (Fig. 3). Patients who experienced MBL had a significantly longer operating time (p < 0.001) and a higher risk of developing other IOC, POC, and overall complications (OR = 2.18, 1.51, 1.63, respectively) than patients who did not experience substantial blood loss. Conclusions The overall incidence of complications was 58% following 3CO surgery. There was significant variation in incidence of complications depending on the number, location, and experience of performing osteotomies. Risks for developing complications included having two osteotomies, ThO, surgery at a low-volume center, and blood loss more than 4 L. With a better understanding of 3CO complications and risk factors, physicians may be more informed in the decision-making process of sagittal plane deformity correction.
Spine | 2015
Robert P. Norton; Kristina Bianco; Christopher S. Klifto; Thomas J. Errico; John A. Bendo
Study Design. Analysis of the Nationwide Inpatient Sample database. Objective. To investigate national trends, risks, and benefits of surgical interventions for degenerative spondylolisthesis (DS). Summary of Background Data. The surgical management of DS continues to evolve whereas the most clinically and cost-effective treatment is debated. With an aging US population and growing restraints on a financially burdened health care system, a clear understanding of national trends in the surgical management of DS is needed. Methods. The Nationwide Inpatient Sample database was queried for patients with DS undergoing lumbar fusions from 2001 to 2010, using International Classification of Diseases, Ninth Revision (ICD-9) diagnosis and procedure codes. Analyses compared instrumented posterolateral fusion (PLF), posterolateral fusion with anterior lumbar interbody fusion (ALIF + PLF), PLF with posterior interbody fusion (P/TLIF + PLF), anterior instrumented interbody fusion (ALIF), and posterior interbody fusion with posterior instrumentation (P/TLIF). Clinical data were analyzed representing the initial acute phase care after surgery. Results. There were 48,911 DS surgical procedures identified, representing 237,383 procedures. The percentage of patients undergoing PLF, ALIF + PLF, or ALIF increased whereas the percentage of P/TLIF or P/TLIF + PLF decreased over time. Total charges were less (P < 0.001), average length of hospital stay was shorter (P < 0.01), and average age was older (P < 0.01) for patients who underwent PLF compared with any other procedure. Type of procedure varied on the basis of the geographic region of the hospital, teaching versus nonteaching hospital, and size of hospital (P < 0.01). Patients who had P/TLIF + PLF or ALIF had a higher risk of mortality than patients who had PLF (odds ratios: 5.02, 2.22, respectively). Patients were more likely to develop a complication if they had ALIF + PLF, P/TLIF + PLF, ALIF, and P/TLIF than if they had PLF (odds ratios: 1.45, 1.23, 1.49, 1.12, respectively). Conclusion. Variation in the surgical management of DS related to patient demographics, hospital charges, length of hospital stay, insurance type, comorbidities, and complication rates was found within the Nationwide Inpatient Sample database. During the acute phase of care immediately after surgery, PLF procedures were found to reduce length of hospital stay, hospital charges, and postoperative complications. Level of Evidence: 3
Spine | 2014
Jonathan Falakassa; Brandon P. Hirsch; Robert P. Norton; Matthew Mendez-Zfass; Frank J. Eismont
Study Design. Retrospective clinical case series. Objective. To report on the epidemiological, microbiological, and clinical characteristics of spinal infections in patients who have undergone solid organ transplantation. Summary of Background Data. Spine infections remain a therapeutic challenge, particularly in patients who are immunocompromised. Solid organ transplant patients represent a growing population of immunocompromised hosts. To our knowledge, no previous reports have examined the clinical characteristics spinal infections in this at-risk population in a systematic fashion. Methods. The records of patients with a history of solid organ transplantation from January 2007 through December 2012 were identified using Current Procedural Terminology procedure codes. Patients with spine infections who have received transplants were then identified using International Classification of Diseases, Ninth Revision codes for spine infection. In addition to demographic data, we recorded medical comorbidities, immunosuppressant medications, laboratory results, culture data, treatment received, and short-term results. Results. During this 6-year period, 2764 solid organ transplants were performed at our institution. Of this cohort, 6 patients (0.22%) were treated for a spinal infection. Patients age ranged from 51 to 80 years (mean, 63 yr). All spine infections occurred within 1 year after organ transplantation. All patients had an elevated erythrocyte sedimentation rate. Only 1 patient had an elevated white blood cell count. The most common organisms were Escherichia coli and Staphylococcus. Four patients required surgical treatment. All patients had complete resolution of symptoms. Conclusion. Our data suggest that patients with a history of solid organ transplantation may be more susceptible to developing spine infections than the general population. The most common organisms in our cohort were E. coli and Staphylococcus. Spine infections caused by atypical organisms do also occur in the organ transplant population, as is the case in other immunocompromised patients. The identification of these organisms and timely institution of treatment remains critical in the management of this at-risk population. Level of Evidence: 4
Archive | 2015
Justin C. Paul; Robert P. Norton; Themistocles S. Protopsaltis
Archive | 2015
Robert P. Norton; Justin C. Paul; Themistocles S. Protopsaltis