ABSTRACT
OBJECTIVE: Lumbar interbody spacers are widely used in lumbar spinal fusion. The goal of this study is to analyze the biomechanics of a lumbar interbody spacer (Clydesdale Spinal System, Medtronic Sofamor Danek, Memphis, Tennessee, USA) inserted via oblique lumbar interbody fusion (OLIF) or direct lateral interbody fusion (DLIF) approaches, with and without posterior cortical screw and rod (CSR) or pedicle screw and rod (PSR) instrumentation. METHODS: Lumbar human cadaveric specimens (L2-L5) underwent nondestructive flexibility testing in intact and instrumented conditions at L3-L4, including OLIF or DLIF, with and without CSR or PSR. RESULTS: OLIF alone significantly reduced range of motion (ROM) in flexion-extension (P = 0.005) but not during lateral bending or axial rotation (P ≥ 0.63). OLIF alone reduced laxity in the lax zone (LZ) during flexion-extension (P < 0.001) but did not affect the LZ during lateral bending or axial rotation (P ≥ 0.14). The stiff zone (SZ) was unaffected in all directions (P ≥ 0.88). OLIF plus posterior instrumentation (cortical, pedicle, or hybrid) reduced the mean ROM in all directions of loading but only significantly so with PSR during lateral bending (P = 0.004), without affecting the compressive stiffness (P > 0.20). The compressive stiffness with the OLIF device without any posterior instrumentation did not differ from that of the intact condition (P = 0.97). In terms of ROM, LZ, or SZ, there were no differences between OLIF and DLIF as standalone devices or OLIF and DLIF with posterior instrumentation (CSR or PSR) (P > 0.5). CONCLUSIONS: OLIF alone significantly reduced mobility during flexion-extension while maintaining axial compressive stiffness compared with the intact condition. Adding posterior instrumentation to the interbody spacer increased the construct stability significantly, regardless of cage insertion trajectory or screw type.
Subject(s)
Internal Fixators , Spinal Fusion/instrumentation , Benzophenones , Biomechanical Phenomena , Cadaver , Female , Humans , Ketones , Lumbar Vertebrae , Male , Middle Aged , Polyethylene Glycols , PolymersABSTRACT
Corpus callosotomy has been used as a form of surgical palliation for patients suffering from medically refractory generalized seizures, including drop attacks. Callosotomy has traditionally been described as involving a craniotomy with microdissection. MR-guided laser interstitial thermal therapy (MRg-LITT) has recently been used as a minimally invasive method for performing surgical ablation of epileptogenic foci and corpus callosotomy. The authors present 3 cases in which MRg-LITT was used to perform a corpus callosotomy as part of a staged surgical procedure for a patient with multiple seizure types and in instances when further ablation of residual corpus callosum is necessary after a prior open surgical procedure. To the authors' knowledge, this is the first case series of corpus callosotomy performed using the MRg-LITT system with a 3.3-year average follow-up. Although MRg-LITT is not expected to replace the traditional corpus callosotomy in all cases, it is a safe, effective, and durable alternative to the traditional open corpus callosotomy, particularly in the setting of a prior craniotomy.
Subject(s)
Corpus Callosum/surgery , Drug Resistant Epilepsy/surgery , Epilepsy, Generalized/surgery , Laser Therapy/methods , Magnetic Resonance Imaging, Interventional/methods , Syncope/surgery , Adolescent , Corpus Callosum/diagnostic imaging , Drug Resistant Epilepsy/complications , Drug Resistant Epilepsy/drug therapy , Epilepsy, Generalized/complications , Epilepsy, Generalized/drug therapy , Female , Hemispherectomy , Humans , Infant , Magnetic Resonance Imaging , Male , Robotic Surgical Procedures/methods , Syncope/etiology , Treatment Outcome , Young AdultABSTRACT
OBJECTIVESpine surgery is less common in children than adults. These surgeries, like all others, are subject to complications such as bleeding, infection, and CSF leak. The rate of incidental durotomy in the pediatric population, and its associated complications, has scarcely been reported in the literature.METHODSThis is a retrospective chart review of all pediatric patients operated on at Wake Forest Baptist Health from 2012 to 2017 who underwent spine surgeries. The authors excluded any procedures with intended durotomy, such as tethered cord release or spinal cord tumor resection.RESULTSFrom 2012 to 2017, 318 pediatric patients underwent surgery for a variety of indications, including adolescent idiopathic scoliosis (51.9%), neuromuscular scoliosis (27.4%), thoracolumbar fracture (2.83%), and other non-fusion-related indications (3.77%). Of these patients, the average age was 14.1 years, and 71.0% were female. There were 6 total incidental durotomies, resulting in an overall incidence of 1.9%. The incidence was 18.5% in revision operations, compared to 0.34% for index surgeries. Comparison of the revision cohort to the durotomy cohort revealed a trend toward increased length of stay, operative time, and blood loss; however, the trends were not statistically significant. The pedicle probe was implicated in 3 cases and the exact cause was not ascertained in the remaining 3 cases. The 3 durotomies caused by pedicle probe were treated with bone wax; 1 was treated with dry Gelfoam application and 2 were treated with primary repair. Only 1 patient had a persistent leak postoperatively that eventually required wound revision.CONCLUSIONSIncidental durotomy is an uncommon occurrence in the pediatric spinal surgery population. The majority occurred during placement of pedicle screws, and they were easily treated with bone wax at the time of surgery. Awareness of the incidence, predisposing factors, and treatment options is important in preventing complications and disability.
Subject(s)
Dura Mater/injuries , Intraoperative Complications/epidemiology , Spine/surgery , Adolescent , Child , Child, Preschool , Female , Humans , Incidence , Infant , Infant, Newborn , Male , Scoliosis/surgeryABSTRACT
BACKGROUND: Occipital condyle fractures (OCFs) have traditionally been described based on anatomic characteristics; however, recent literature has proposed management based on biomechanical stability and neural element compression. The treatment of biomechanically stable fractures varies between observation and cervical immobilization. Before determining the best management approach, an understanding of concomitant cervical spine fractures in the presence of OCFs is important. The primary aim of this pilot study was to determine the rate of occurrence of biomechanically significant cervical spine fractures with OCFs. METHODS: A retrospective chart review was performed of 13,363 patients presenting to a level 1 trauma center between 2013 and 2017 with a diagnosis of OCF. RESULTS: Forty-six patients presented with OCFs, with an average Glasgow Coma Scale score of 12 on presentation and an average Injury Severity Score of 23. The average patient age was 42.1 years, and 4 patients had bilateral OCFs. Approximately 30% of these patients had associated intracranial injuries and 59% had an associated cervical spine injury. The overall rate of associated potentially biomechanically significant cervical spine fracture was 43.5%. Treatment of OCFs included collar immobilization (83%) and observation (17%). The average duration of follow-up was 3.37 months. CONCLUSIONS: This study characterizes cervical spine fractures that occur concomitantly with OCFs. The results indicate that more than one-half of patients with OCFs do not have biomechanically significant fractures elsewhere in the cervical spine. This subset of patients will be the cohort for a prospective study to assess whether collar immobilization is necessary.
Subject(s)
Cervical Vertebrae/injuries , Disease Management , Mandibular Condyle/injuries , Occipital Bone/injuries , Spinal Fractures/therapy , Adult , Cervical Vertebrae/diagnostic imaging , Cohort Studies , Female , Follow-Up Studies , Humans , Male , Mandibular Condyle/diagnostic imaging , Occipital Bone/diagnostic imaging , Pilot Projects , Retrospective Studies , Spinal Fractures/diagnostic imagingABSTRACT
OBJECTIVE: Recently developed expandable interbody spacers are widely accepted in spinal surgery; however, the resulting biomechanical effects of their use have not yet been fully studied. We analyzed the biomechanical effects of an expandable polyetheretherketone interbody spacer inserted through a bilateral posterior approach with and without different modalities of posterior augmentation. METHODS: Biomechanical nondestructive flexibility testing was performed in 7 human cadaveric lumbar (L2-L5) specimens followed by axial compressive loading. Each specimen was tested under 6 conditions: 1) intact, 2) bilateral L3-L4 cortical screw/rod (CSR) alone, 3) WaveD alone, 4) WaveD + CSR, 5) WaveD + bilateral L3-L4 pedicle screw/rod (PSR), and 6) WaveD + CSR/PSR, where CSR/PSR was a hybrid construct comprising bilateral cortical-level L3 and pedicle-level L4 screws interconnected by rods. RESULTS: The range of motion (ROM) with the interbody spacer alone decreased significantly compared with the intact condition during flexion-extension (P = 0.02) but not during lateral bending or axial rotation (P ≥ 0.19). The addition of CSR or PSR to the interbody spacer alone condition significantly decreased the ROM compared with the interbody spacer alone (P ≤ 0.002); and WaveD + CSR, WaveD + PSR, and WaveD + CSR/PSR (hybrid) (P ≥ 0.29) did not differ. The axial compressive stiffness (resistance to change in foraminal height during compressive loading) with the interbody spacer alone did not differ from the intact condition (P = 0.96), whereas WaveD + posterior instrumentation significantly increased compressive stiffness compared with the intact condition and the interbody spacer alone (P ≤ 0.001). CONCLUSIONS: The WaveD alone significantly reduced ROM during flexion-extension while maintaining the axial compressive stiffness. CSR, PSR, and CSR/PSR hybrid constructs were all effective in augmenting the expandable interbody spacer system and improving its stability.
Subject(s)
Biomechanical Phenomena/physiology , Lumbar Vertebrae/surgery , Lumbosacral Region/surgery , Adult , Cadaver , Female , Humans , Internal Fixators , Lumbosacral Region/pathology , Male , Middle Aged , Pedicle Screws , Range of Motion, Articular/physiology , Spinal Fusion/methodsABSTRACT
Current diagnosis of chronic Chagas disease relies on serologic detection of specific immunoglobulin G against Trypanosoma cruzi. However, the presence of parasites detected by polymerase chain reaction (PCR) in patients without positive conventional serologic testing has been observed. We determined the prevalence and clinical characteristics of persons with seronegative results and T. cruzi DNA detected by PCR in a population at high risk for chronic American trypanosomiasis. We studied a total of 194 persons from two different populations: 110 patients were recruited from an urban cardiology clinic, and 84 persons were citizens from a highly disease-endemic area. Eighty (41%) of persons had negative serologic findings; 12 (15%) had a positive PCR. Three patients with negative serologic findings and positive PCR results had clinical signs and symptoms that suggested Chagas cardiomyopathy. This finding challenges the current recommendations for Chagas disease diagnosis, therapy, and blood transfusion policies.
Subject(s)
Chagas Disease/parasitology , Trypanosoma cruzi/isolation & purification , Adolescent , Adult , Aged , Animals , Antibodies, Protozoan/blood , Argentina/epidemiology , Chagas Disease/epidemiology , Cross-Sectional Studies , DNA, Protozoan/chemistry , DNA, Protozoan/genetics , Enzyme-Linked Immunosorbent Assay , Female , Fluorescent Antibody Technique, Indirect , Hemagglutination Inhibition Tests , Humans , Male , Middle Aged , Polymerase Chain Reaction , Rural Population , Seroepidemiologic Studies , Trypanosoma cruzi/genetics , Urban PopulationABSTRACT
La informática es la disciplina que eficentemente procesa todos los datos necesarios para obtener información. La aquisición de datos, procesamiento e interpretación es realizada a través de medios tradicionales como así también automatizados. La informática médica es la unión de todos los métodos de informática en medicina incluyendo la preparación de los datos médicos requeridos para la aplicación de estos métodos. Debido a la necesidad de conservar , procesar y analizar eficientemente el incremento de datos que la medicina moderna está recibiendo, paa obtener de ellos información significativa, nosotros proponemos la creación de un departamento de Informática Médica en nuestra Facultad de Medicina para : 1) Enseñar los principios básicos de la informática médica a los estudiantes y graduados, incluyendo clases de: técnicas en información, terminología médica, linguística médica, clasificación internacional de las enfermedades, sistemas informáticos hospitalarios, aplicación práctica de la computación en medicina como Oncocyn Mycin, etc. Así como bases de datos externos; 2) Ayudar al personal de las ciencias de la salud para obtener y transferir información médica a través del correo electrónico de la red académica nacional e internacional
Subject(s)
Medical Informatics/education , Education, Medical , Schools, MedicalABSTRACT
La informática es la disciplina que eficentemente procesa todos los datos necesarios para obtener información. La aquisición de datos, procesamiento e interpretación es realizada a través de medios tradicionales como así también automatizados. La informática médica es la unión de todos los métodos de informática en medicina incluyendo la preparación de los datos médicos requeridos para la aplicación de estos métodos. Debido a la necesidad de conservar , procesar y analizar eficientemente el incremento de datos que la medicina moderna está recibiendo, paa obtener de ellos información significativa, nosotros proponemos la creación de un departamento de Informática Médica en nuestra Facultad de Medicina para : 1) Enseñar los principios básicos de la informática médica a los estudiantes y graduados, incluyendo clases de: técnicas en información, terminología médica, linguística médica, clasificación internacional de las enfermedades, sistemas informáticos hospitalarios, aplicación práctica de la computación en medicina como Oncocyn Mycin, etc. Así como bases de datos externos; 2) Ayudar al personal de las ciencias de la salud para obtener y transferir información médica a través del correo electrónico de la red académica nacional e internacional (AU)
