Study Design The biomechanical stability of seven cervical reconstruction methods including the transpedicular screw fixation was evaluated under four instability patterns. These modalities, based on range and grade instability, allowed a reproducible assessment to establish in vitro role internal spine. Objectives This study biomechanically investigated spine as influenced by patterns assessed whether three-column for using transpedicula would provide increased over that conventional...

There is currently no structured classification system to quantitate heterotopic bone formation after artificial disk replacement procedures. The purpose of this work was develop a method classifying that reliable between investigators with different levels training and easy remember only five gradations severity. One hundred one radiographs clinical patients 17 microradiographs from nonhuman primates having undergone various types were classified by seven independent reviewers. κ statistics...

Fluxion testing was performed until failure on 66 lumbosacral bovine spinal segments comparing ten different Instrumentation techniques. Maximum flexion moment at failure, flexural stiffness, and maximum angulation of the joint were determined as well strain measurements across anterior aspect intervertebral disc using an extensometer. The significantly greater for only two devices that extended fixation into ilium to projected image middle osteoligamentous column: ISOLA Galveston Iljac...

In vitro investigation of cervical adjacent level intradiscal pressures (IDPs) following a total disc replacement arthroplasty.The current in study was undertaken to compare IDPs and operative kinematics arthroplasty versus an arthrodesis procedure.Clinical data indicate the incidence symptomatic transition syndrome be as high 3% annually interbody arthrodesis. Recent developments motion preservation technology should, theory, minimize at levels.A 10 human cadaveric spines were used this...

In Brief Study Design. A prospective, randomized, multicenter, Food and Drug Administration-regulated, investigational device exemption clinical trial. Objectives. To compare the safety effectiveness of lumbar total disc replacement (TDR) with CHARITÉ™ artificial (DePuy Spine, Raynham, MA) to anterior interbody fusion for treatment single-level degenerative disease from L4–S1 unresponsive nonoperative treatment. addition, evaluate radiographic outcomes at either L4–L5 or L5–S1 as compared...

Study Design. An in vitro biomechanical analysis of three anterior instability patterns was performed using calf lumbosacral spines. Stiffness the constructs compared, and segmental motion analyses were performed. Objectives. To clarify factors that alter stability spinal instrumentation to evaluate influence on residual intact segments. Summary Background Data. Recently, many adverse effects have been reported fusion augmented with rigid instrumentation. Only few reports are available...

Study Design. This in vitro biomechanical study was undertaken to quantify the multidirectional intervertebral kinematics following total disc replacement arthroplasty compared conventional stabilization techniques. Objective. Using an human cadaveric model, primary objective compare flexibility properties and map center of rotation versus threaded fusion cages augmented with transpedicular fixation for single-level spinal instrumentation. Summary Background Data. The utilization...

In vitro biomechanical testing was performed in human cadaveric lumbar spines, using pressure needle transducers to analyze the effects of spinal destabilization and instrumentation on intradiscal pressures.To quantify changes pressures at three adjacent disc levels under conditions reconstruction, evaluate possibility pressure-induced pathology secondary instrumentation.Lumbar vivo use development have been investigated comprehensively. However, not delineated clearly.In 11 lumbosacral...

An animal model of anterior and posterior column instability was developed to allow in vivo observation bone remodeling arthrodesis after spinal instrumentation. After an initial destabilizing lesion created at the L5-L6 vertebral levels 42 adult beagles, various reconstructive surgical procedures were performed--with or without bilateral posterolateral grafting, with instrumentation (Harrington distraction; Luque rectangular, Cotrel-Dubousset transpedicular methods). 6 months' postoperative...

Study Design. A biomechanical study on cadaveric thoracic vertebrae using pullout strength, insertional torque, and bone mineral density to determine the optimal sagittal trajectory of pedicle screws. Objective. To perform a for placement We compared straight-forward (paralleling vertebral endplate) with anatomic (directed along true axis pedicle). Methods. Thirty were harvested evaluated dual-energy x-ray absorptiometry assess density. Matched, fixed-head screws then randomly assigned by...

Study Design. In vitro biomechanical testing of the strength and stability lumbosacral fixation constructs. Objectives. The purpose this study was to quantify compare properties five different constructs determine benefit adding supplementary S1 screws. Summary Background Data. Extension long fusions sacrum remains a difficult clinical challenge. Only limited number studies have evaluated methods available, none has included both nondestructive load failure these methods. Methods. Six...

Biomechanical evaluation of twelve different spinal devices in vitro employing pedicle screws was performed using static (n = 5) and cyclical testing 3) parameters. In general, the rank order implant failures similar between tests, performed, at 600 N compressive load, 5 Hz, 1 million cycles. The mean number cycles to failure higher for instrumentation Systems longitudinal rods than those plates (ANOVA F 16.94, P < .001). At N, compact Cotrel-Dubousset, TSRH, ISOLA rod systems demonstrated...

Study Design A carbon fiber-reinforced polymer implant, designed to aid interbody lumbar fusion, was tested biologically in an experimental surgical model. Twenty-seven Spanish goats had fusion surgery a randomized protocol. Seventeen were implanted with the cage packed autologous bone, and 10 ethylene oxide-sterilized allograft bone. Objectives To determine success, biocompatibility of material, possibility wear debris at intervals after implantation. Methods Goats killed 6 months, 12 24...

The current study of 251 consecutive 1-level anterior cervical reconstructions was undertaken to compare the incidence dysphagia between disk replacement and conventional fusion instrumentation.This is a report patients from 5 investigational centers in Food drug Administration's prospective, randomized porous-coated motion (PCM) trial using validated outcomes instrument. data for both PCM diskectomy (ACDF) were reviewed (1) severity dysphagia, (2) postoperative (3) resolution perioperative...

The stabilizing effects of five different occipitocervical fixations were compared.To evaluate the construct stability provided by occipito-atlanto-axial fixation techniques.Few studies have addressed reconstruction and no to data investigated anterior-posterior translational stiffness.A total 21 human cadaveric spines used. After testing intact (CO-C2), a type II dens fracture was created reconstructions performed: 1) occipital sublaminar wiring/rectangular rod, 2) screws C2 lamina claw...

Study Design. Using an in vivo interbody arthrodesis model, the efficacy of Bagby and Kuslich (BAK) device packed with recombinant human osteogenic protein-1 (rhOP-1) was evaluated. Objectives. To compare protein that autograft for arthrodesis, fusion success based on biomechanical, histologic, radiographic analyses. Summary Background Data. The use bone morphogenetic proteins (rhBMPs) as osteoinductive graft substitutes or expanders has recently gained considerable research interest,...

An animal model of anterior and posterior cojumn instability was developed to allow in vivo observation bone remodeling arthrodesis following spinal instrumentation. After an initial destabilizing lesion created at the L5-L6 vertebral levels 63 adult beagles, various reconstructive surgical procedures were performed—with or without bilateral posterolateral grafting, with oophorectomies, instrumentation (Harrington distraction, Luque rectangular, Cotrel- Dubousset pedicular, Steffee pedicular...

Study Design. In an in vivo sheep model, the effects of spinal fusion and kyphotic deformity on neighboring motion segments were analyzed. Objectives. To investigate adjacent segment. Summary Background Data. The have not been investigated any studies. Methods. Eighteen equally randomized into three groups based surgical procedure: L3–L5 situ posterolateral (n = 6) 6), exposure alone 6). After a 16-week survival period, segment changes analyzed radiographically, biomechanically,...

In Brief Study Design. This study retrospectively examines outcomes of unilateral transforaminal lumbar interbody fusion (TLIF) with posterior fixation using anterior carbon fiber cages and 360° in spondylolisthesis. Objectives. The goals were to examine the perioperative complications column support treatment various types Summary Background Data. 2000, Brantigan et al reported cage used as a US IDE clinical trial. is largest series date TLIF specifically Methods. A comprehensive long-term...

Study Design. Five different reconstructions of the atlantoaxial complex were biomechanically compared in vitro a nondestructive test. Objectives. To determine whether non–bone graft–dependent one-point fixation affords stability levels equivalent to three-point reconstructions. Summary Background Data. Previous investigations have demonstrated that fixation, using bilateral transarticular screws combination with posterior wiring, provide most effective resistance minimize motion around...

Object. Interbody fusion devices are rapidly gaining acceptance as a method of ensuring lumbar interbody arthrodesis. Although different types have been developed, the comparative reconstruction stability remains controversial. It also unclear how stress-shielded environments created within devices. Using calf spine model, this study was designed to compare construct stiffness afforded by 11 differently and quantify their stress-shielding effects measuring pressure Methods. Sixty-six...

Study Design. The efficacy of posterior instrumentations for treating thoracolumbar burst fractures to restore spinal alignment and indirectly reduce intracanal bone fragments was investigated. Also, a biomechanical study performed compare the mechanical stability anterior instrumentations. Methods. Twenty-four fresh human cadaveric spine segments were used. After clinically identical L1 created, two used alignment: 1) Harrington dual distraction rods with sleeves 2) AO internal fixator....

In Brief Study Design. A prospective, randomized, multicenter, FDA-regulated Investigational Device Exemption clinical trial. Objectives. To analyze the incidence of, and reasons for, reoperation in all patients (treatment control) enrolled IDE study. Summary of Background Data. This is first report nature reoperations following lumbar TDR as part a controlled, multicenter Methods. total 688 meeting inclusion exclusion criteria were one three arms study at 14 centers across United States....

Sixty patients with one-level discogenic pain confirmed by plain radiography, magnetic resonance imaging, and provocative discography for degenerative disc disease were randomized: one-third BAK anterior interbody fusion two-thirds SB Charité artificial replacement. The mean age was 40.3 years (range 21–56 years). Nineteen cases at L4–L5 41 L5–S1. had randomized as length of surgery 88.4 minutes 54–137 minutes) both groups. estimated blood loss 289.5 mL 50–1800 mL). hospital stay a 3.03 days...