STUDY DESIGN: An in vitro biomechanical study of one-level and three-level corpectomy and anterior cervical plate models. OBJECTIVE: To investigate the failure of the screw-vertebra interfaces in one- and three-level corpectomy models. SUMMARY AND BACKGROUND DATA: Although there are several biomechanical studies of strength and stability of anterior cervical plating, ...

STUDY DESIGN: An in vitro investigation of three-dimensional kinematics of cervical spine models of one- and three-level corpectomy with anterior plate fixation. OBJECTIVES: To evaluate the capability of an anterior plate to stabilize the reconstructed cervical spine under simulated physiologic motions, and to study the effects of fatigue loading. SUMMARY ...

OBJECTIVE: To develop a new sitting spinal model and an optimal driver's seat by using review of the literature of seated positions of the head. spine, pelvis, and lower extremities. DATA SELECTION: Searches included MEDLINE for scientific journals, engineering standards, and textbooks. Key terms included sitting ergonomics, sitting posture, spine ...

STUDY DESIGN: An in vitro test of calf spine lumbar segments to compare biomechanical stabilization of a rigid versus a dynamic posterior fixation device. OBJECTIVES: To compare flexibility of a dynamic pedicle screw fixation device with an equivalent rigid device. SUMMARY OF BACKGROUND DATA: Dynamic pedicle screw device studies are ...

Several studies have examined the functional relationship between mandibular movement and head or body posture, but head and body motion during jaw movement have not been extensively investigated. Ten healthy participants performed repetitive jaw tapping movement. Piezoelectric accelerometers were attached on the surfaces of the participant's forehead, mentum, and over ...

OBJECTIVE. The aim of the study was to compare lumbar range of motion determined using two computerised dynamic motion analysis devices. BACKGROUND: Measures of spinal motion are currently used in biomechanical, epidemiological and clinical studies of the low back. It is essential that the various devices used to measure mobility ...

STUDY DESIGN: In an in vivo sheep model, the effects of spinal fusion and kyphotic deformity on the neighboring motion segments were analyzed. OBJECTIVES: To investigate the effects of spinal fusion and kyphotic deformity on the adjacent motion segment. SUMMARY OF BACKGROUND DATA: The in vivo effects of kyphotic deformity ...

OBJECTIVE: To investigate the specificity of linear and angular displacement, peak velocity and frequency of oscillation of the frontal plane motion produced by the lateral glide treatment technique of the cervical spine. DESIGN: A within-subjects design was used. BACKGROUND: The lateral glide treatment technique of the cervical spine has previously ...

STUDY DESIGN: Direct measurement of intervertebral motion was compared to motion determined by measuring the position of the exposed ends of the external fixation pins. OBJECTIVES: To verify the accuracy of this technique, so that this protocol can be used to study intervertebral motion in the clinical setting. SUMMARY OF ...

STUDY DESIGN: The influence of lumbar disc height and cross-sectional area on the mechanical response of the disc to physiologic loading was determined using a finite element model. OBJECTIVES: To identify which geometric characteristics are potentially related to motion segment mechanical response to applied load, such as flexibility, fiber stress, ...

STUDY DESIGN: Single-group repeated measures for single rater reliability. OBJECTIVES: To describe the intratester reliability for measurements of active lumbar spine mobility and pelvic inclination during standing obtained with the back range-of-motion (BROM) device. BACKGROUND: The BROM device has often been used to quantify lumbar spine active range of motion. ...

OBJECTIVE: Establishment of a normal database and clinical reference of active global cervical spine motion ranges and patterns using a commercial electrogoniometer. DESIGN: Three-dimensional cervical motion ranges and patterns were analyzed in 250 asymptomatic volunteers. BACKGROUND: In vivo out-of-plane motion patterns of the cervical spine have not yet been reported ...

This paper describes a method for applying controlled loads to a lumbar vertebra while recording in vivo from primary afferents innervating the lumbar paraspinal tissues. Unlike the appendicular skeleton, the vertebral column poses a unique challenge for neurophysiological investigations. Distances between paraspinal tissues and the spinal cord are short. In ...

OBJECTIVES: This study investigated the sequence of intervertebral joint movements and range of motion during three tasks involving lumbar flexion. DESIGN: Position sensors were used to measure position and rotation of lumbar vertebrae during unconstrained flexion. BACKGROUND: In the development of mathematical models, numerous assumptions need to be made. Few ...

STUDY DESIGN: Relative phase angle was used to study segmental motion patterns during a lifting and lowering task. OBJECTIVES: To investigate the effect of back belts, breathing technique, and their interaction on lumbar and pelvic motion patterns. SUMMARY OF BACKGROUND DATA: Trunk and pelvic coordination has been investigated in healthy ...

STUDY DESIGN: A study of inter- and intra-examiner reliability and clinical validity using two instruments for assessment of spinal range of motion in healthy individuals. OBJECTIVE: To assess the clinical validity, stability, and normative values for active and passive cervical range of motion as measured by the CA-6000 (Orthopedic Systems ...

To determine the effect that ventral intervertebral disk fenestration has on the sagittal range of motion about the C5-C6 intervertebral space. A repeated measures in vitro mechanical study of spinal range of motion under controlled loading conditions before and after fenestration. A total of 10 canine cervical vertebral specimens (C4-C7) ...

OBJECTIVE: To characterize typical spinal motions that occur during standing reach and to describe differences in spinal motions and center of pressure displacements during reach between younger and older healthy adults. DESIGN: Exploratory, cross sectional investigation utilizing video motion and biomechanics force platform analysis. BACKGROUND: Standing reach provides a means ...

STUDY DESIGN: The motion of each cervical vertebra during simulated rear-end car collisions was analyzed. OBJECTIVES: To clarify the mechanism of zygapophysial joint injury during whiplash loading. SUMMARY OF BACKGROUND DATA: The zygapophysial joint is the suspected origin of neck pain after rear-end car collision. However, no studies have been ...

STUDY DESIGN: Compressive loading of the lumbar spine was analyzed using electromyographic, movement analysis, and force-plate techniques. OBJECTIVES: To evaluate the inertial forces that cannot be detected by electromyographic techniques alone. SUMMARY OF BACKGROUND DATA: Links between back pain and manual labor have stimulated attempts to measure spine compressive loading. ...

Facet joints provide rigidity to the lumbar motion segment and thus protect the disk, particularly against torsional injury. A surgical procedure that fully or partially removes the facet joints (facetectomy) will decrease the mechanical stiffness of the motion segment, and potentially place the disk at risk of injury. Analytical models ...

STUDY DESIGN: Cervical motion patterns were analyzed in a normal population and in patients with cervical instability by using cineradiography. OBJECTIVES: To determine normal and pathologic motion patterns in the cervical spine through an in vivo continuous motion analysis. SUMMARY OF BACKGROUND DATA: Cineradiographic techniques have been used in a ...

OBJECTIVE: The study determined the effect of variations in the material properties of the cervical spinal components on the output of the finite element analysis (external and internal responses of the cervical spine) under physiologic load vectors. DESIGN: A three-dimensional (3D) anatomically accurate finite element model comprising of the C4-C5-C6 ...

This study was done to determine the motion of the whole lumbar spine after internal fixation and the effect of kyphosis and lordosis on the remaining vertebral levels. Baseline motion analysis of sagittal, frontal, and transverse planes was done to determine the intact range of motion. Three fusion configurations were ...

The Kluger internal fixator, with its artificial fulcrum outside the operative site, had to be extended for multisegmental use. Three different prototypes, called Central Bar (CB), Double Bar I (DB I) and Double Bar II (DB II) were designed, which were fully compatible with the existing reduction system. To evaluate ...

OBJECTIVE: To determine the optimal contractile response of isolated ureters to inflammatory mediators and neurotransmitters by evaluating four common methods of ureteric suspension. MATERIALS AND METHODS: Ureters from adult domestic swine were placed immediately in Krebs buffer and cut into 4-5 mm segments. Four methods of suspension were compared: (i) ...

A thoracolumbar spine model was made using synthetic resin vertebrae and silicon discs. The model was fixed to a metal frame and spinal deformation caused by loading was determined relative to three-dimensional coordinates set in the frame. A three-dimensional evaluation of the development of spinal deformity was performed by applying ...

OBJECTIVE: This study was conducted to evaluate the kinematic response of late fusion results for cervical spine discectomies with and without bone grafting. MATERIALS AND METHODS: Fifteen Barbados Black Belly sheep underwent sham operations (Group A, n = 5), C2-C3 discectomies only (Group B, n = 5), and C2-C3 discectomies ...

The motion of the thoracic and lumbar spine segments was analysed by mean of the skin landmarks method in 14 volunteers (7 males, 7 females). The results demonstrated that there was no significant difference between men and women and there was either facilitation or limitation of the motion of the ...

OBJECTIVE: To determine whether the three-dimensional (3-D) lumbar spine kinematics for the mixed fast bowling technique differed to those of the side-on and front-on fast bowling techniques. BACKGROUND: It has been previously shown that bowlers who utilise a mixed bowling technique are more likely to show lumbar spine pathology than ...

STUDY DESIGN: Sagittal plane translatory and rotatory motion was measured in 15 lumbar motion segments of 8 patients by distortion-compensated and stereophotogrammetric Roentgen analysis. OBJECTIVE: To compare measurement precision of the new distortion-compensated Roentgen analysis protocol with that of the established Roentgen stereophotogrammetric technique under realistic clinical conditions. SUMMARY OF ...

OBJECTIVES: To compare the effectiveness of an upper cervical manipulation and a manipulation of the sacroiliac joint for increasing hip range of motion. DESIGN: Clinical cohort study. SETTING: Macquarie University Centre for Chiropractic Outpatient Clinic. SAMPLE: Fifty-two randomly chosen university students aged 18 to 34 yr. METHOD: A reliable hand-held ...

This study investigates whether the path taken by the fingertips of the human hand during unrestricted flexion and extension follows a precise mathematical pattern: an equiangular spiral. Eight normal subjects participated in the study. Subjects performed numerous flexion and extension trials at a random speed. Motion was recorded by a ...

STUDY DESIGN: Biomechanical and anatomic study of human cadaveric spinal motion segments. OBJECTIVES: To measure the stiffness of spinal motion segments by disc type and by load type (flexion, extension, axial rotation, or lateral bending). To compare stiffness in motion segments with and without a high-intensity zone or radial tear ...

STUDY DESIGN: Dynamic lumbar flexion-extension motion was assessed by videofluoroscopy. OBJECTIVES: To identify the motion patterns of the whole lumbar spine in normal subjects and in patients with low back pain or spondylolisthesis during actual movement. SUMMARY OF BACKGROUND DATA: Assessment of lumbar instability on terminal radiographs is controversial. Information ...

STUDY DESIGN: The acute kinematic consequence of segmental arthrodesis in the cervical spine on the remaining open motion segments was studied in a cadaveric model. OBJECTIVES: To evaluate the distribution of motion across unfused cervical motion segments after a segmental arthrodesis. The applied load was determined as a function of ...

BACKGROUND: Cervical extrication collars are used in the evacuation of the injured to minimize secondary injury. These collars were designed for extrication and evacuation, not for longterm use, and complications have been reported when they have been used in the rehabilitation phase. The Newport/Aspen collar was designed specifically for long-term ...

STUDY DESIGN: An in vitro biomechanical analysis of three anterior instability patterns was performed using calf lumbosacral spines. Stiffness of the constructs was compared, and segmental motion analyses were performed. OBJECTIVES: To clarify the factors that alter the stability of the spinal instrumentation and to evaluate the influence of instrumentation ...

OBJECTIVE: To describe the natural variation of the active and passive cervical range of motion (ROM) in asymptomatic subjects over a 3-wk period. STUDY DESIGN: One-way repeated measures of active and passive cervical ROM. SETTING: Institute of Medical Biology (Center of Biomechanics) at Odense University, Denmark. PARTICIPANTS: Forty asymptomatic students ...

The present study examined organizational patterns of individual muscular contributions to head and neck motion. Previous studies of asymptomatic subjects with cervical motor asymmetry identified significant kinematic and myoelectric alterations. The current study evaluated 34 asymptomatic subjects categorized as to symmetry group based on initial palpatory test comparing regional motion ...

Magnified Chemiluminescent Examination (MCE) or speculoscopy is a new visual method for detection of cervical neoplasia. It utilizes low magnification and a special "blue-white" chemiluminescent light. The study includes 125 women with unhealthy cervix who were subjected to magnified examination with projected incandescent light (PIL) and chemiluminescent light (MCE). This ...

STUDY DESIGN: The quantitative anthropometry of the cervical longitudinal ligaments was determined in 20 human cadaveric subatlantal cervical spines at the limits of flexion and extension. OBJECTIVES: To provide measurements of cervical anterior and posterior longitudinal ligament lengths, widths, and cross-sectional areas at segmental levels. SUMMARY OF BACKGROUND DATA: Although ...

Reduction in lumbar muscular activity at full body flexion, known as flexion relaxation, has been studied in relation to overall trunk, lumbar spine, and hip flexion, but has not been evaluated in conjunction with motion on the segmental level. In this study, intervertebral motion in a lumbar motion segment, trunk ...

A new Intervertebral Motion Device (IMD) was developed in this study. Depending on its configuration, the IMD was used to measure motion in the sagittal, frontal, and transverse planes. Calibration results showed that the root-mean-square (RMS) error of the IMD was 0.092 mm in axial translation, 0.065 mm in shear ...

STUDY DESIGN: The multidirectional stability potential of anterior, posterior, and combined instrumentations applied at L1-L3 was studied after L2 corpectomy and replacement with a carbon-fiber implant. OBJECTIVES: To evaluate the biomechanical characteristics of short-segment anterior, posterior, and combined instrumentations in lumbar spine tumor vertebral body replacement surgery. SUMMARY OF BACKGROUND ...

OBJECTIVE: To analyze the coordination of the lumbo-sacral angle (lumbar spine lordosis) and the trunk inclination during lifting of different loads. STUDY DESIGN: Kinematic data of spine motion were analyzed. The parameters characterizing the relationships between the lordosis and the trunk inclination angle were estimated. BACKGROUND: The shape of the ...

SUMMARY. Following the independent development in the University of Brighton of a new skin fixation system for use with the OSI CA 6000 Spine Motion Analyzer (SMA), a series of studies was initiated to test the reliability of the instrument with the new skin fixation system, and the repeatability of ...

SUMMARY. Physiotherapists commonly use motion testing techniques in the assessment of patients with spinal disorders. One of the techniques considered important in the assessment of low back pain is the application of posteroanterior (PA) forces to the lumbar spinous processes to evaluate spinal stiffness and symptom response. The purpose of ...

OBJECTIVE: To determine whether belt wearing causes changes in lumbar posture and motion during standing and work-related activities. DESIGN: The lumbar spine sagittal kinematics of healthy subjects were assessed with an electrogoniometer during a dynamic test and continuous recording with and without a lumbar support. Correlation between data from electrogoniometer ...

This paper proposes an anatomical parameter, the pelvic incidence, as the key factor for managing the spinal balance. Pelvic and spinal sagittal parameters were investigated for normal and scoliotic adult subjects. The relation between pelvic orientation, and spinal sagittal balance was examined by statistical analysis. A close relationship was observed, ...