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1.
Am J Emerg Med ; 35(11): 1630-1635, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28511807

RESUMEN

OBJECTIVE: Prehospital personnel who lack advanced airway management training must rely on basic techniques when transporting unconscious trauma patients. The supine position is associated with a loss of airway patency when compared to lateral recumbent positions. Thus, an inherent conflict exists between securing an open airway using the recovery position and maintaining spinal immobilization in the supine position. The lateral trauma position is a novel technique that aims to combine airway management with spinal precautions. The objective of this study was to compare the spinal motion allowed by the novel lateral trauma position and the well-established log-roll maneuver. METHODS: Using a full-body cadaver model with an induced globally unstable cervical spine (C5-C6) lesion, we investigated the mean range of motion (ROM) produced at the site of the injury in six dimensions by performing the two maneuvers using an electromagnetic tracking device. RESULTS: Compared to the log-roll maneuver, the lateral trauma position caused similar mean ROM in five of the six dimensions. Only medial/lateral linear motion was significantly greater in the lateral trauma position (1.4mm (95% confidence interval [CI] 0.4, 2.4mm)). CONCLUSIONS: In this cadaver study, the novel lateral trauma position and the well-established log-roll maneuver resulted in comparable amounts of motion in an unstable cervical spine injury model. We suggest that the lateral trauma position may be considered for unconscious non-intubated trauma patients.


Asunto(s)
Vértebras Cervicales/lesiones , Traumatismos del Cuello/terapia , Posicionamiento del Paciente/métodos , Rango del Movimiento Articular , Traumatismos Vertebrales/terapia , Anciano , Anciano de 80 o más Años , Manejo de la Vía Aérea/métodos , Fenómenos Biomecánicos , Cadáver , Estudios Cruzados , Servicios Médicos de Urgencia/métodos , Femenino , Humanos , Disco Intervertebral/lesiones , Ligamento Amarillo/lesiones , Ligamentos Longitudinales/lesiones , Masculino , Persona de Mediana Edad , Médula Espinal , Fracturas de la Columna Vertebral , Posición Supina
2.
J Emerg Med ; 50(3): 427-32, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26475486

RESUMEN

BACKGROUND: It has been proposed that cricoid pressure can exacerbate an unstable cervical injury and lead to neurologic deterioration. OBJECTIVE: We sought to examine the amount of motion cricoid pressure could cause at an unstable subaxial cervical spine injury, and whether posterior manual support is of any benefit. METHODS: Five fresh, whole cadavers had complete segmental instability at C5-C6 surgically created by a fellowship-trained spine surgeon. Cricoid pressure was applied to the anterior cricoid by an attending anesthesiologist. In addition, the effect of posterior cervical support was tested during the trials. The amount of angular and linear motion between C5 and C6 was measured using a Fastrak, three-dimensional, electromagnetic motion analysis device (Polhemus Inc., Colchester, VT). RESULTS: When cricoid pressure is applied, the largest angular motion was 3 degrees and occurred in flexion-extension at C5-C6. The largest linear displacement was 1.36 mm and was in anterior-posterior displacement of C5-C6. When manual posterior cervical support was applied, the flexion-extension was improved to less than half this value (1.43 degrees), and this reached statistical significance (p = 0.001). No other differences were observed to be significant in the other planes of motion with the applications of support. CONCLUSIONS: Based on the evidence presented, we believe that the application of cricoid pressure to a patient with a globally unstable subaxial cervical spine injury causes small displacements. There may be some benefit to the use of manual posterior cervical spine support for reducing motion at such an injured segment.


Asunto(s)
Vértebras Cervicales/lesiones , Cartílago Cricoides/fisiología , Inestabilidad de la Articulación/fisiopatología , Traumatismos del Cuello/fisiopatología , Presión/efectos adversos , Traumatismos Vertebrales/fisiopatología , Anciano de 80 o más Años , Fenómenos Biomecánicos , Cadáver , Vértebras Cervicales/fisiopatología , Femenino , Humanos , Masculino , Rango del Movimiento Articular/fisiología
3.
J Emerg Med ; 50(5): 728-33, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26531709

RESUMEN

BACKGROUND: A patient with a suspected cervical spine injury may be at risk for secondary neurologic injury when initially placed and repositioned to the center of the spine board. OBJECTIVES: We sought to determine which centering adjustment best limits cervical spine movement and minimizes the chance for secondary injury. METHODS: Using five lightly embalmed cadaveric specimens with a created global instability at C5-C6, motion sensors were anchored to the anterior surface of the vertebral bodies. Three repositioning methods were used to center the cadavers on the spine board: horizontal slide, diagonal slide, and V-adjustment. An electromagnetic tracking device measured angular (degrees) and translation (millimeters) motions at the C5-C6 level during each of the three centering adjustments. The dependent variables were angular motion (flexion-extension, axial rotation, lateral flexion) and translational displacement (anteroposterior, axial, and medial-lateral). RESULTS: The nonuniform condition produced significantly less flexion-extension than the uniform condition (p = 0.048). The horizontal slide adjustment produced less cervical flexion-extension (p = 0.015), lateral bending (p = 0.003), and axial rotation (p = 0.034) than the V-adjustment. Similarly, translation was significantly less with the horizontal adjustment than with the V-adjustment; medial-lateral (p = 0.017), axial (p < 0.001), and anteroposterior (p = 0.006). CONCLUSIONS: Of the three adjustments, our team found that horizontal slide was also easier to complete than the other methods. The horizontal slide best limited cervical spine motion and may be the most helpful for minimizing secondary injury based on the study findings.


Asunto(s)
Vértebras Cervicales/lesiones , Inmovilización/instrumentación , Inmovilización/normas , Movimiento , Movimiento y Levantamiento de Pacientes/métodos , Posicionamiento del Paciente/normas , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Cadáver , Femenino , Humanos , Inmovilización/estadística & datos numéricos , Inestabilidad de la Articulación/complicaciones , Inestabilidad de la Articulación/enfermería , Masculino , Movimiento y Levantamiento de Pacientes/enfermería , Movimiento y Levantamiento de Pacientes/estadística & datos numéricos , Traumatismos del Cuello/complicaciones , Posicionamiento del Paciente/métodos , Traumatismos Vertebrales/complicaciones
4.
Prehosp Emerg Care ; 18(4): 539-43, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24878332

RESUMEN

STUDY OBJECTIVE: To compare the amount of segmental vertebral motion produced with the lateral recovery position and the HAINES technique when performed on cadavers with destabilized cervical spines. METHODS: The cervical spines of 10 cadavers were surgically destabilized at the C5-C6 vertebral segment. Sensors from an electromagnetic tracking device were affixed to the vertebrae in question to monitor the amount of anterior/posterior, medial/lateral, and distraction/compression linear motion produced during the application of the two study techniques. RESULTS: The statistical analysis of linear motion data did not reveal any significant differences between the two recovery positions. CONCLUSION: At this time, no single version of the recovery position can be endorsed for the spine-injured trauma patient. More research is needed to fully ascertain the safety of commonly used recovery positions.


Asunto(s)
Vértebras Cervicales/lesiones , Inmovilización , Rango del Movimiento Articular/fisiología , Traumatismos Vertebrales/fisiopatología , Transporte de Pacientes/métodos , Anciano , Anciano de 80 o más Años , Cadáver , Femenino , Humanos , Inmovilización/métodos , Masculino , Postura , Medición de Riesgo
5.
Anesth Analg ; 117(1): 126-32, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23354337

RESUMEN

BACKGROUND: The effects of advanced airway management on cervical spine alignment in patients with upper cervical spine instability are uncertain. METHODS: To examine the potential for mechanical disruption during endotracheal intubation in cadavers with unstable cervical spines, we performed a prospective observational cohort study with 3 cadaver subjects. We created an unstable, type II odontoid fracture with global ligamentous instability at C1-2 in lightly embalmed cadavers, followed by repetitive intubations with 4 different airway devices (Airtraq laryngoscope, Lightwand, intubating laryngeal mask airway [LMA], and Macintosh laryngoscope) while manual in-line stabilization was applied. Motion analysis data were collected using an electromagnetic device to assess the degree of angular movement in 3 axes (flexion-extension, axial rotation, and lateral bending) during the intubation trials with each device. Intubation was performed by either an emergency medical technician or attending anesthesiologist. RESULTS: Overall, 153 intubations were recorded with the 4 devices. The Lightwand technique resulted in significantly less flexion-extension and axial rotation at C1-2 than with the intubating LMA (mean difference in flexion-extension 3.2° [95% confidence interval {CI}, 0.9°-5.5°], P = 0.003; mean difference in axial rotation 1.6° [95% CI, 0.3°-2.8°], P = 0.01) and Macintosh laryngoscope (mean difference in flexion-extension 3.1° [95% CI, 0.8°-5.4°], P = 0.005; mean difference in axial rotation 1.4° [95% CI 0.1°-2.6°], P = 0.03). CONCLUSIONS: In cadavers with instability at C1-2, the Lightwand technique produced less motion than the Macintosh and intubating LMA.


Asunto(s)
Intubación Intratraqueal/instrumentación , Intubación Intratraqueal/métodos , Inestabilidad de la Articulación , Ligamentos/lesiones , Apófisis Odontoides/lesiones , Fracturas de la Columna Vertebral , Anciano , Anciano de 80 o más Años , Vértebras Cervicales/lesiones , Estudios de Cohortes , Humanos , Intubación Intratraqueal/normas , Inestabilidad de la Articulación/complicaciones , Máscaras Laríngeas/normas , Estudios Prospectivos , Fracturas de la Columna Vertebral/complicaciones
6.
J Spinal Cord Med ; 36(1): 58-65, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23433336

RESUMEN

CONTEXT: Excessive spinal motion generated during multiple bed transfers of patients with unstable spine injuries may contribute to neurological deterioration. OBJECTIVE: To evaluate spinal motion in a cadaveric model of global spinal instability during hospital bed transfers using several commonly used techniques. DESIGN/PARTICIPANTS: A motion analysis and evaluation of hospital bed transfer techniques in a cadaveric model of C5-C6 and T12-L2 global spinal instability. Setting/outcome measures: Global instability at C5-C6 and T12-L2 was created. The motion in three planes was measured in both the cervical and lumbar spine during each bed transfer via electromagnetic motion detection devices. Comparisons between transfers performed using an air-assisted lateral transfer device, manual transfer, a rolling board, and a sliding board were made based on the maximum range of motion observed. RESULTS: Significantly less lateral bending at C5-C6 was observed in air-assisted device transfers when compared with the two other boards. Air-assisted device transfers produced significantly less axial rotation at T12-L2 than the rolling board, and manual transfers produced significantly less thoracolumbar rotation than both the rolling and sliding boards. No other significant differences were observed in cervical or lumbar motion. Motion versus time plots indicated that the log roll maneuvers performed during rolling board and sliding board transfers contributed most of the observed motion. CONCLUSIONS: Each transfer technique produced substantial motion. Transfer techniques that do not include the logroll maneuver can significantly decrease some components of cervical and lumbar motion. Thus, some spinal motion can be reduced through selection of transfer technique.


Asunto(s)
Lechos , Equipos y Suministros de Hospitales , Movimiento (Física) , Movimiento y Levantamiento de Pacientes , Columna Vertebral/fisiología , Transporte de Pacientes/métodos , Fenómenos Biomecánicos/fisiología , Cadáver , Humanos
7.
J Emerg Med ; 45(3): 366-71, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23849357

RESUMEN

BACKGROUND: As prehospital emergency rescuers prepare cervical spine-injured adult patients for immobilization and transport to hospital, it is essential that patients be placed in a favorable position. Previously, it was recommended that patients with cervical spine injuries be immobilized in a slightly flexed position using pads placed beneath the head. However, it is unknown how neck flexion created with pad placement affects the unstable spine. OBJECTIVE: To determine the effects of three different head positions on the alignment of unstable vertebral segments. METHODS: Five cadavers with a complete segmental instability at the C5 and C6 level were included in the study. The head was either placed directly on the ground (or spine board) or on foam pads. Three conditions were tested: no pad; pads 2.84 cm thick; and pads 4.26 cm thick. Pads were positioned beneath the head to determine their effect on spinal alignment. Anterior-posterior translation, flexion-extension motion, and axial displacement across the unstable segment were compared between conditions. RESULTS: Although statistical tests failed to identify any significant differences between pad conditions, some meaningful results were noted. In general, the "no pad" condition aligned the spine in a position that best replicated the intact spine. CONCLUSIONS: Because the goal of emergency rescuers is to conserve whatever physiologic or structural integrity of the spinal cord and spinal column that remains, the outcome of this study suggests that this goal may be best achieved using the "no pad" condition. However, it is recommended that more research be conducted to confirm these preliminary findings.


Asunto(s)
Vértebras Cervicales/lesiones , Servicios Médicos de Urgencia/métodos , Inestabilidad de la Articulación/prevención & control , Posicionamiento del Paciente/métodos , Anciano , Cadáver , Femenino , Humanos , Inmovilización , Masculino , Persona de Mediana Edad , Transporte de Pacientes , Articulación Cigapofisaria/fisiopatología
8.
J Spinal Cord Med ; 35(1): 53-7, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22330191

RESUMEN

INTRODUCTION: Previous research has found that the log roll (LR) technique produces significant motion in the spinal column while transferring a supine patient onto a spine board. The purpose of this project was to determine whether log rolling a patient with an unstable spine from prone to supine with a pulling motion provides better thoracolumbar immobilization compared to log rolling with a push technique. METHODS: A global instability was surgically created at the L1 level in five cadavers. Two spine-boarding protocols were tested (LR Push and LR Pull). Both techniques entailed performing a 180° LR rotation of the prone patient from the ground to the supine position on the spine board. An electromagnetic tracking device registered motion between the T12 and L2 vertebral segments. Six motion parameters were tracked. Repeated-measures statistical analysis was performed to evaluate angular and translational motion. RESULTS: Less motion was produced during the LR Push compared to the LR Pull for all six motion parameters. The difference was statistically significant for three of the six parameters (flexion-extension, axial translation, and anterior-posterior (A-P) translation). CONCLUSIONS: Both the LR Push and LR Pull generated significant motion in the thoracolumbar spine during the prone to supine LR. The LR Push technique produced statistically less motion than the LR Pull, and should be considered when a prone patient with a suspected thoracolumbar injury needs to be transferred to a long spine board. More research is needed to identify techniques to further reduce the motion in the unstable spine during prone to supine LR.


Asunto(s)
Vértebras Lumbares/fisiología , Movimiento (Física) , Enfermedades de la Columna Vertebral/fisiopatología , Transporte de Pacientes/métodos , Fenómenos Biomecánicos , Cadáver , Humanos , Posición Prona , Rango del Movimiento Articular/fisiología , Transporte de Pacientes/normas
9.
J Trauma ; 70(5): 1282-5; discussion 1285, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21610441

RESUMEN

BACKGROUND: After spine board immobilization of the trauma victim and transport to the hospital, the patient is removed from the spine board as soon as practical. Current Advanced Trauma Life Support's recommendations are to log roll the patient 90 degrees, remove the spine board, inspect and palpate the back, and then log roll back to supine position. There are several publications showing unacceptable motion in an unstable spine when log rolling. METHODS: Cervical spine motion was evaluated during spine board removal. A C5 to C6 instability was surgically created in cadavers. A three-dimensional electromagnetic tracking system was used to assess motion between C5 and C6. The log roll was compared with a lift-and-slide technique. Throughout the log roll procedure, manual inline cervical stabilization was provided by a trained individual in a series of trials. In other trials, the lift-and-slide technique was used. In the final stage, the amount of motion generated was assessed when the spine board removal techniques were completed by experienced and novice persons in maintaining inline stabilization of the head and neck. RESULTS: Motion between C5 and C6 was reduced during the lift-and-slide technique in five of six parameters. The reduction was statistically significant in four parameters. When performing the log roll, motion was not reduced with increased head holder experience. CONCLUSIONS: Spine boards can be removed using a lift-and-slide maneuver with less motion and potentially less risk to the patient's long-term neurologic function than expected using the log roll.


Asunto(s)
Vértebras Cervicales/lesiones , Inmovilización/instrumentación , Elevación , Movimiento (Física) , Equipo Ortopédico , Traumatismos Vertebrales/terapia , Transporte de Pacientes/métodos , Fenómenos Biomecánicos , Cadáver , Vértebras Cervicales/fisiopatología , Humanos , Traumatismos Vertebrales/fisiopatología
10.
J Emerg Med ; 41(5): 513-9, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21397431

RESUMEN

BACKGROUND: Cervical orthoses are commonly used for extrication, transportation, and definitive immobilization for cervical trauma patients. Various designs have been tested frequently in young, healthy individuals. To date, no one has reported the effectiveness of collar immobilization in the presence of an unstable mid-cervical spine. STUDY OBJECTIVES: To determine the extent to which cervical orthoses immobilize the cervical spine in a cadaveric model with and without a spinal instability. METHODS: This study used a repeated-measures design to quantify motion on multiple axes. Five lightly embalmed cadavers with no history of cervical pathology were used. An electromagnetic motion-tracking system captured segmental motion at C5-C6 while the spine was maneuvered through the range of motion in each plane. Testing was carried out in intact conditions after a global instability was created at C5-C6. Three collar conditions were tested: a one-piece extraction collar (Ambu Inc., Linthicum, MD), a two-piece collar (Aspen Sierra, Aspen Medical Products, Irvine, CA), and no collar. Gardner-Wells tongs were affixed to the skull and used to apply motion in flexion-extension, lateral bending, and rotation. Statistical analysis was carried out to evaluate the conditions: collar use by instability (3 × 2). RESULTS: Neither the one- nor the two-piece collar was effective at significantly reducing segmental motion in the stable or unstable condition. There was dramatically more motion in the unstable state, as would be expected. CONCLUSION: Although using a cervical collar is better than no immobilization, collars do not effectively reduce motion in an unstable cervical spine cadaver model. Further study is needed to develop other immobilization techniques that will adequately immobilize an injured, unstable cervical spine.


Asunto(s)
Tirantes/normas , Vértebras Cervicales/lesiones , Inmovilización/instrumentación , Inestabilidad de la Articulación/terapia , Fenómenos Biomecánicos , Cadáver , Fenómenos Electromagnéticos , Humanos , Persona de Mediana Edad , Adulto Joven
11.
Am J Emerg Med ; 28(7): 751-6, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20837250

RESUMEN

INTRODUCTION: In the prehospital setting, spine-injured patients must be transferred to a spine board to immobilize the spine. This can be accomplished using both manual techniques and mechanical devices. OBJECTIVES: The study aimed to evaluate the effectiveness of the scoop stretcher to limit cervical spine motion as compared to 2 commonly used manual transfer techniques. METHODS: Three-dimensional angular motion generated across the C5-C6 spinal segment during execution of 2 manual transfer techniques and the application of a scoop stretcher was recorded first on cadavers with intact spines and then repeated after C5-C6 destabilization. A 3-dimensional electromagnetic tracking device was used to measure the maximum angular and linear motion produced during all test sessions. RESULTS: Although not statistically significant, the execution of the log roll maneuver created more motion in all directions than either the lift-and-slide technique or with scoop stretcher application. The scoop stretcher and lift-and-slide techniques were able to restrict motion to a comparable degree. CONCLUSION: The effectiveness of the scoop stretcher to limit spinal motion in the destabilized spine is comparable or better than manual techniques currently being used by primary responders.


Asunto(s)
Vértebras Cervicales , Servicios Médicos de Urgencia/métodos , Movimiento y Levantamiento de Pacientes/instrumentación , Traumatismos Vertebrales , Anciano de 80 o más Años , Análisis de Varianza , Fenómenos Biomecánicos , Cadáver , Vértebras Cervicales/lesiones , Fenómenos Electromagnéticos , Diseño de Equipo , Humanos , Imagenología Tridimensional , Inmovilización/instrumentación , Rango del Movimiento Articular , Rotación , Seguridad , Traumatismos Vertebrales/diagnóstico , Traumatismos Vertebrales/fisiopatología , Traumatismos Vertebrales/prevención & control , Transporte de Pacientes/métodos
12.
J Spinal Disord Tech ; 22(6): 399-403, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19652564

RESUMEN

STUDY DESIGN: Direct and scatter radiation was measured during cadaveric cervical spine imaging with a mini-C-arm fluoroscope. OBJECTIVE: The purpose of this study was to evaluate radiation exposure to the patient and surgeon when using a mini-C-arm fluoroscope to image the cervical spine. SUMMARY OF BACKGROUND DATA: Prior studies have quantified radiation exposure using large C-arm fluoroscopy during procedures involving the cervical, thoracic, and lumbar spine. To our knowledge, no studies have quantified radiation exposure during mini-C-arm fluoroscopy of the cervical spine. METHODS: A calibrated OEC MINI 6800 C-arm was used to image a prepared cadaveric cervical spine specimen, which included the skull. The specimen was suspended on an adjustable polycarbonate platform. Thirteen film badge dosimeters were mounted at various positions and angles to detect direct and scatter radiation. Recorded exposure levels were collected and analyzed. RESULTS: Surgeon exposures from the mini-C-arm were considerably lower than previously reported with the standard C-arm, but nonetheless concerning. Patient exposures were considerable and not always reduced compared with values from the standard C-arm. The kVp generated by the mini-C-arm was similar to the standard C-arm. Dosimeters mounted in the same plane recorded dissimilar amounts of radiation during the same test, which underscores the influence of shape on the amount of reflected scatter. CONCLUSIONS: Although using a mini-C-arm unit may reduce exposure levels, substantial exposure to both patient and staff is still achievable. Use of a mini-C-arm for cervical spine imaging reduces exposure to the surgeon more effectively than to the patient. To lower the risk of radiation exposure in the cadaver laboratory, a mini-C-arm should be used in each instance that offers appropriate visualization. In the operating room, all appropriate radiation dose-reducing measures should be strictly enforced by supervising physicians to minimize risk to patients, medical staff, and themselves.


Asunto(s)
Vértebras Cervicales/diagnóstico por imagen , Seguridad de Equipos/métodos , Fluoroscopía/efectos adversos , Fluoroscopía/métodos , Traumatismos por Radiación/prevención & control , Protección Radiológica/métodos , Cadáver , Diseño de Equipo/métodos , Seguridad de Equipos/instrumentación , Fluoroscopía/instrumentación , Humanos , Enfermedad Iatrogénica/prevención & control , Exposición Profesional/efectos adversos , Dosis de Radiación , Efectos de la Radiación , Monitoreo de Radiación/métodos , Protección Radiológica/instrumentación , Factores de Riesgo , Dispersión de Radiación , Enfermedades de la Columna Vertebral/diagnóstico por imagen
13.
Spine J ; 8(5): 717-22, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17983846

RESUMEN

BACKGROUND CONTEXT: Two common justifications for orienting cervical screws in an angled direction are to increase pullout strength and to allow use of longer screws. This concept is widely taught and has guided implant design. Fixed- versus variable-angle systems may offer strength advantages. Despite these teachings, there is a paucity of supporting biomechanical evidence. The purpose of our study is to test the influence of screw orientation and plate design on the maximum screw pullout force. PURPOSE: This study evaluates the effect of screw orientation and plate type (fixed- vs. variable-angle) on screw pullout strength. STUDY DESIGN: Anterior cervical plates of both a fixed- and variable-angle CSLP, were tested for peak pullout strength in a direct plate pullout model using polyurethane foam bone, which models osteoporotic bone. METHODS: Self-tapping, locking screws (4.0x14mm and 4.0x16mm) were used. Screws were oriented in the fixed-angle plate in the standard fashion. In the variable plate, screws were instrumented in three different orientations. Biomechanical testing was performed on an Instron DynaMight 8841 servohydraulic testing machine, measuring maximum pullout force under a displacement-controlled pullout rate of 1mm/min. Five samples were tested per group. RESULTS: When all screws were placed 90 degrees to the plate, there was a significantly increased peak pullout strength (412.8+/-22.2N) compared with when all screws were placed 12 degrees "up and in" (376.2+/-24.3N, p less than or equal to .03). When the 90 degrees construct was reproduced using 14-mm screws and compared with 16-mm screws oriented 12 degrees "all up and in," there was still significantly higher pullout strength with the all 90 degrees construct (434.2+/-28.7N vs. 376.2+/-24.3N, p less than or equal to .009). The fixed-angle plate had a significantly decreased peak pullout strength (288.2+/-15.7N) compared with the variable-angle plate (416.6+/-12.6N) (p less than .00001) when the screws were placed in the same orientation. Overall, the variable-angle plate, regardless of the orientation of screws, had a significantly greater pullout strength than the fixed-angle plate (p less than .001). CONCLUSIONS: In this system, a variable-angle plate has greater pullout strength than a fixed-angle plate, regardless of the orientation of screws. With the variable-angle plate, a construct of all screws 12 degrees "up and in" is the weakest configuration. We found that with the 90 degrees construct, both 16- and 14-mm screws performed significantly better than 16-mm convergent screws. These findings are remarkable because they contradict the current doctrine. This may be a function of plate-dependent factors and should not be applied universally to all plate systems. Further study of screw orientation in additional plating systems is warranted.


Asunto(s)
Placas Óseas , Tornillos Óseos , Análisis de Falla de Equipo , Procedimientos Ortopédicos/instrumentación , Fenómenos Biomecánicos , Vértebras Cervicales/cirugía , Ensayo de Materiales
14.
J Neurosurg Spine ; 6(6): 540-3, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17561742

RESUMEN

OBJECT: The purpose of the present study was to compare spinal motion generated during log-rolling and kinetic therapy with that generated when using a kinetic treatment table (KTT). The authors' hypothesis was that the KTT would produce less spinal motion while maintaining the benefits of body position changes. METHODS: Cervical and lumbar instability was created in three fresh, unembalmed cadavers. Electromagnetic sensors were fixed to the C5-6 and T12-L2 segments to measure cervical and lumbar spine segmental motion. Body position changes were performed using the traditional log-roll method and a KTT. Spinal motion was measured during each maneuver. Turning the cadaveric specimens on the KTT bed caused significantly less cervical motion than the log-roll technique as measured in flexion and axial rotation. The log-roll technique caused significantly greater cervical motion during body position changes than turning using the KTT. CONCLUSIONS: Although the global instability will require surgical stabilization, consideration should be given to initial immobilization on a KTT to decrease the likelihood of secondary injury.


Asunto(s)
Manipulación Ortopédica/métodos , Movimiento (Física) , Postura , Traumatismos de la Médula Espinal/fisiopatología , Columna Vertebral/fisiopatología , Cadáver , Vértebras Cervicales/fisiopatología , Humanos , Inestabilidad de la Articulación/fisiopatología , Vértebras Lumbares/fisiopatología , Manipulación Ortopédica/instrumentación , Rotación
15.
J Neurosurg Spine ; 7(2): 161-4, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17688055

RESUMEN

OBJECT: The purpose of this study was to compare manual maneuvering with the use of a Jackson table when moving patients with cervical spine instability from the supine to the surgically appropriate prone position. METHODS: The range of motion (ROM) of the cervical spine of a fresh cadaver was measured. A ligamentous instability was created at the C5-6 level, and the increased ROM was confirmed. Sensors for an electromagnetic motion analysis device were fixed to the anterior portions of the C-5 and C-6 vertebral bodies (VBs) using machined polyethylene mounts and carbon fiber rods that were inserted into the VBs. The sensors were used to measure cervical flexion, lateral bending, and axial rotation during the two transfer procedures. The cadaver was then moved from the supine position on a hospital bed to the prone position for surgery. The manual technique was performed by four trained individuals who moved the cadaver from the hospital bed while rotating it 180 degrees axially onto the surgical table. In using the Jackson table, the cadaver was moved from the bed to the table in the supine position and then the Jackson table rotated the cadaver to the prone position. The two techniques were tested with and without the use of a collar and were repeated five times. RESULTS: Analysis of the data indicated that when moving a patient into the prone surgical position, the use of a cervical collar and the Jackson table significantly reduced the cervical motion in all angular planes compared with that of manual transfer. CONCLUSIONS: The use of a cervical collar and the Jackson table may reduce the possibility of further spinal cord compromise. Because manual transfers are performed routinely, this warrants further study.


Asunto(s)
Vértebras Cervicales/fisiopatología , Inestabilidad de la Articulación/fisiopatología , Posición Prona , Rango del Movimiento Articular , Enfermedades de la Columna Vertebral/fisiopatología , Equipo Quirúrgico , Lechos , Tirantes , Cadáver , Fenómenos Electromagnéticos , Humanos , Inestabilidad de la Articulación/cirugía , Rotación , Enfermedades de la Columna Vertebral/cirugía , Posición Supina
16.
Spine (Phila Pa 1976) ; 42(24): E1398-E1402, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-28591075

RESUMEN

STUDY DESIGN: A biomechanical cadaveric study. OBJECTIVE: We sought to determine the amount of motion generated in an unstable cervical spine fracture with use of the vacuum mattress versus the spine board alone. Our hypothesis is that the vacuum mattress will better immobilize an unstable cervical fracture. SUMMARY OF BACKGROUND DATA: Trauma patients in the United States are immobilized on a rigid spine board, whereas in many other places, vacuum mattresses are used with the proposed advantages of improved comfort and better immobilization of the spine. METHODS: Unstable subaxial cervical injuries were surgically created in five fresh whole human cadavers. The amount of motion at the injured motion segment during testing was measured using a Fastrak, three-dimensional, electromagnetic motion analysis device (Polhemus Inc.). The measurements recorded in this investigation included maximum displacements during application and removal of the device, while tilting to 90°, during a bed transfer, and a lift onto a gurney. Linear and angular displacements were compared using the Generalized Linear Model analysis of variance for repeated measures for each of the six dependent variables (three planes of angulations and three axes of displacement). RESULTS: There was more motion in all six planes of motion during the application process with use of the spine board alone, and this was statistically significant for axial rotation (P = 0.011), axial distraction (P = 0.035), medial-lateral translation (P = 0.027), and anteroposterior translation (P = 0.026). During tilting, there was more motion with just the spine board, but this was only statistically significant for anteroposterior translation (P = 0.033). With lifting onto the gurney, there was more motion with the spine board in all planes with statistical significance, except lateral bending. During the removal process, there was more motion with the spine board alone, and this was statistically significant for axial rotation (P = 0.035), lateral bending (P = 0.044), and axial distraction (P = 0.023). CONCLUSION: There was more motion when using a spine board alone during typical maneuvers performed during early management of the spine injured patient than the vacuum mattress. There may be benefit of use of the vacuum mattress versus the spine board alone in preventing motion at an unstable, subaxial cervical spine injury. LEVEL OF EVIDENCE: 2.


Asunto(s)
Vértebras Cervicales/lesiones , Equipo Ortopédico , Restricción Física/métodos , Traumatismos Vertebrales/fisiopatología , Fenómenos Biomecánicos/fisiología , Cadáver , Vértebras Cervicales/fisiopatología , Humanos , Rango del Movimiento Articular/fisiología , Vacio
17.
Spine J ; 17(8): 1061-1065, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-27939747

RESUMEN

BACKGROUND CONTEXT: Determining pain intensity is largely dependent on the patient's report. PURPOSE: The objective of this study was to test the hypothesis that patients initially reporting a pain score of 10 out of 10 on the visual analog scale (VAS) would experience symptom improvement to a degree similar to patients reporting milder pain. STUDY DESIGN: This study is a retrospective chart review. PATIENT SAMPLE: A total of 6,779 patients seeking care for spinal disorders were included in the study. OUTCOME MEASURES: The outcome measures used in the study were pain scores on the VAS pain scale, smoking status, morbid depression, gender, and the presence of known secondary gain. MATERIALS AND METHODS: Patients with lumbar degenerative disk disease with or without spinal stenosis who reported a VAS pain score of 10 out of 10 were identified. Changes in reported VAS pain, patient age, smoking status, morbid depression, gender, and the presence of known secondary gain were examined. RESULTS: A total of 160 individuals (2.9%) reported a maximum pain score of 10 out of 10 on a VAS at their initial presentation. The patients had a median improvement of 3 points in reported VAS pain between the first visit and the last follow-up appointment. The odds to improve by at least 40% on the VAS were 1.500 (95% confidence interval 1.090-2.065) compared with patients reporting submaximal pain. The proportion of patients with identifiable secondary gain was higher (p=.001) than that of patients with submaximal pain. Patients whose pain scores improved dramatically (ie, at least 4 points on the VAS) tended to be older (p=.001), to less often have secondary gain from their disease (p=.007), and to have a negative current smoking status (p=.002). Patients whose pain remained 10 out of 10 during the course of treatment smoked more frequently (p=.016). CONCLUSIONS: Our analysis supports the need to consider the influence of secondary gain on the patients' reported VAS pain scores. Maximum pain seems to be a more acute phenomenon with some likelihood to significantly improve.


Asunto(s)
Dolor de Espalda/diagnóstico , Degeneración del Disco Intervertebral/diagnóstico , Dimensión del Dolor/métodos , Estenosis Espinal/diagnóstico , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor/normas
18.
Spine J ; 16(8): 927, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27545399

RESUMEN

Commentary On: Thesleff T, Niskakangas T, Luoto TM, Öhman J, Ronkainen A. Fatal cervical spine injuries: a Finnish nationwide register-based epidemiological study on data from 1987 to 2010. Spine J 2016:16:918-26 (in this issue).


Asunto(s)
Vértebras Cervicales/lesiones , Traumatismos Vertebrales , Demografía , Finlandia , Humanos
19.
Injury ; 47(3): 717-20, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26777467

RESUMEN

OBJECTIVES: Pelvic circumferential compression devices are commonly used in the acute treatment of pelvic fractures for reduction of pelvic volume and initial stabilisation of the pelvic ring. There have been reports of catastrophic soft-tissue breakdown with their use. The aim of the current investigation was to determine whether various pelvic circumferential compression devices exert different amounts of pressure on the skin when applied with the force necessary to reduce the injury. The study hypothesis was that the device with the greatest surface area would have the lowest pressures on the soft-tissue. METHODS: Rotationally unstable pelvic injuries (OTA type 61-B) were surgically created in five fresh, whole human cadavers. The amount of displacement at the pubic symphysis was measured using a Fastrak, three-dimensional, electromagnetic motion analysis device (Polhemus Inc., Colchester, VT). The T-POD, Pelvic Binder, Sam Sling, and circumferential sheet were applied in random order for testing. The devices were applied with enough force to obtain a reduction of less than 10mm of diastasis at the pubic symphysis. Pressure measurements, force required, and contact surface area were recorded with a Tekscan pressure mapping system. RESULTS: The mean skin pressures observed ranged from 23 to 31kPa (173 to 233mm of Hg). The highest pressures were observed with the Sam Sling, but no statistically significant skin pressure differences were observed with any of the four devices (p>0.05). The Sam Sling also had the least mean contact area (590cm(2)). In greater than 70% of the trials, including all four devices tested, skin pressures exceeded what has been shown to be pressure high enough to cause skin breakdown (9.3kPa or 70mm of Hg). CONCLUSIONS: Application of commercially available pelvic binders as well as circumferential sheeting commonly results in mean skin pressures that are considered to be above the threshold for skin breakdown. We therefore recommend that these devices only be used acutely, and definitive fixation or external fixation should be performed early as patient physiology allows. There may be some advantage of use of a simple sheet given its low cost, versatility, and ability to alter contact surface area.


Asunto(s)
Fracturas Óseas/patología , Inmovilización/métodos , Aparatos Ortopédicos , Huesos Pélvicos/patología , Presión , Piel/lesiones , Fenómenos Biomecánicos , Cadáver , Fuerza Compresiva , Fijación de Fractura , Fracturas Óseas/terapia , Humanos , Inestabilidad de la Articulación , Guías de Práctica Clínica como Asunto , Piel/patología
20.
Injury ; 47(8): 1801-5, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27324323

RESUMEN

BACKGROUND: Most emergency transport protocols in the United States currently call for the use of a spine board (SB) to help immobilize the trauma patient. However, there are concerns that their use is associated with a risk of pressure ulcer development. An alternative device, the vacuum mattress splint (VMS) has been shown by previous investigations to be a viable alternative to the SB, but no single study has explicated the tissue-interface pressure in depth. METHODS: To determine if the VMS will exert less pressure on areas of the body susceptible to pressure ulcers than a SB we enrolled healthy subjects to lie on the devices in random order while pressure measurements were recorded. Sensors were placed underneath the occiput, scapulae, sacrum, and heels of each subject lying on each device. Three parameters were used to analyze differences between the two devices: 1) mean pressure of all active cells, 2) number of cells exceeding 9.3kPa, and 3) maximal pressure (Pmax). RESULTS: In all regions, there was significant reduction in the mean pressure of all active cells in the VMS. In the number of cells exceeding 9.3kPa, we saw a significant reduction in the sacrum and scapulae in the VMS, no difference in the occiput, and significantly more cells above this value in the heels of subjects on the VMS. Pmax was significantly reduced in all regions, and was less than half when examining the sacrum (104.3 vs. 41.8kPa, p<0.001). CONCLUSION: This study does not exclude the possibility of pressure ulcer development in the VMS although there was a significant reduction in pressure in the parameters we measured in most areas. These results indicate that the VMS may reduce the incidence and severity of pressure ulcer development compared to the SB. Further prospective trials are needed to determine if these results will translate into better clinical outcomes.


Asunto(s)
Lechos , Servicios Médicos de Urgencia , Inmovilización/instrumentación , Traumatismos Vertebrales/prevención & control , Transporte de Pacientes , Adulto , Lechos/efectos adversos , Lechos/economía , Estatura , Índice de Masa Corporal , Peso Corporal , Análisis Costo-Beneficio , Servicios Médicos de Urgencia/economía , Diseño de Equipo , Femenino , Voluntarios Sanos , Humanos , Inmovilización/efectos adversos , Masculino , Persona de Mediana Edad , Úlcera por Presión , Férulas (Fijadores) , Transporte de Pacientes/economía , Transporte de Pacientes/métodos , Estados Unidos , Vacio , Adulto Joven
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