Dynamic Instrumentation of the Thoracic Spine (original) (raw)

Pedicle screw-based dynamic stabilization of the thoracolumbar spine with the Cosmic®-system: a prospective observation

Acta Neurochirurgica, 2010

Object The objective of the study was to generate prospective data to assess the clinical results after dynamic stabilization with the Cosmic® system (Ulrich Medical). Patients and methods Between April 2006 and December 2007, 103 consecutive patients were treated with Cosmic® for painful degenerative segmental instability ± spinal stenosis. The preoperative workup included radiological (MRI and myelography/CT) and clinical parameters (general/neurological examination, visual analogue scale (VAS), Oswestry disability index (ODI), SF-36, Karnofsky (KPS)). At pre-defined intervals (at discharge, 6 weeks, 3 months, 6 months, 12 months, and yearly) the patients were reevaluated (X-ray/flexion/extension, neurological status, VAS, ODI, SF-36, KPS, and patient satisfaction). Data were collected in a prospective observational design. Results Data collection was completed in 100 of 103 operated patients (mean follow-up, 15 ± 0.6 months). Dynamic stabilization was performed as first-tier surgery in 43 cases and as second-tier therapy in 60 cases. Additional decompression was performed in 83 cases. Dynamic stabilization led to significant reduction of back pain-related disability (ODI pre-op, 51 ± 1%; post-op, 21 ± 1%) and improvement of pain (VAS pre-op, 65 ± 1; post-op, 21 ± 2), mental/physical health (norm-based SF-36: mental pre-op, 44; post-op, 48; physical pre-op, 41; post-op, 46), and mobility (KPS pre-op, 70 ± 1; post-op, 82 ± 31). Early reoperation was necessary in 12 patients (n = 3 symptomatic misplaced screws, n = 8 CSF pseudocele, rebleeding, or impaired wound healing, n = 1 misjudged instability/stenosis in adjacent segment). Reoperations within the follow-up period were necessary in another 10 patients due to secondary screw loosening (n = 2), persistent stenosis/disk protrusion in an instrumented segment (n = 3), symptomatic degeneration of an adjacent segment (n = 6), or osteoporotic fracture of an adjacent vertebra (n = 1), respectively. Patient satisfaction rate was 91%. Conclusions Dynamic stabilization with Cosmic® achieved significant improvement of pain, related disability, mental/physical health, and mobility, respectively, and a high rate of satisfied patients. A reoperation rate of 10% during follow-up seems relatively high at first glance. Comparable data, however, are scarce, and a prospective randomized trial (spondylodesis vs. dynamic stabilization) is warranted based on these results.

Clinical analysis of video-assisted thoracoscopic spinal surgery in the thoracic or thoracolumbar spinal pathologies

Journal of Korean …, 2007

ObjectiveThoracoscopic spinal surgery provides minimally invasive approaches for effective vertebral decompression and reconstruction of the thoracic and thoracolumbar spine, while surgery related morbidity can be significantly lowered. This study analyzes clinical results of thoracoscopic spinal surgery performed at our institute.MethodsTwenty consecutive patients underwent video-assisted thoracosopic surgery (VATS) to treat various thoracic and thoracolumbar pathologies from April 2000 to July 2006. The lesions consisted of spinal trauma (13 cases), thoracic disc herniation (4 cases), tuberculous spondylitis (1 case), post-operative thoracolumbar kyphosis (1 case) and thoracic tumor (1 case). The level of operation included upper thoracic lesions (3 cases), midthoracic lesions (6 cases) and thoracolumbar lesions (11 cases). We classified the procedure into three groups: stand-alone thoracoscopic discectomy (3 cases), thoracoscopic fusion (11 cases) and video assisted mini-thoracotomy (6 cases).ResultsAnalysis on the Frankel performance scale in spinal trauma patients (13 cases), showed a total of 7 patients who had neurological impairment preoperatively : Grade D (2 cases), Grade C (2 cases), Grade B (1 case), and Grade A (2 cases). Four patients were neurologically improved postoperatively, two patients were improved from C to E, one improved from grade D to E and one improved from grade B to grade D. The preoperative Cobb's and kyphotic angle were measured in spinal trauma patients and were 18.9±4.4° and 18.8±4.6°, respectively. Postoperatively, the angles showed statistically significant improvement, 15.1±3.7° and 11.3±2.4°, respectively (P<0.001).ConclusionAlthough VATS requires a steep learning curve, it is an effective and minimally invasive procedure which provides biomechanical stability in terms of anterior column decompression and reconstruction for anterior load bearing, and preservation of intercostal muscles and diaphragm.

Analysis of the Active Measurement Systems of the Thoracic Range of Movements of the Spine: A Systematic Review and a Meta-Analysis

Sensors, 2022

Objective: to analyze current active noninvasive measurement systems of the thoracic range of movements of the spine. (2) Methods: A systematic review and meta-analysis were performed that included observational or clinical trial studies published in English or Spanish, whose subjects were healthy human males or females ≥18 years of age with reported measurements of thoracic range of motion measured with an active system in either flexion, extension, lateral bending, or axial rotation. All studies that passed the screening had a low risk of bias and good methodological results, according to the PEDro and MINORS scales. The mean values and 95% confidence interval of the reported measures were calculated for different types of device groups. To calculate the differences between the type of device measures, studies were pooled for different types of device groups using Review Manager software. (3) Results: 48 studies were included in the review; all had scores higher than 7.5 over 10 on the PEDro and MINORs methodological rating scales, collecting a total of 2365 healthy subjects, 1053 males and 1312 females; they were 39.24 ± 20.64 years old and had 24.44 ± 3.81 kg/m2 body mass indexes on average. We summarized and analyzed a total of 11,892 measurements: 1298 of flexoextension, 1394 of flexion, 1021 of extension, 491 of side-to-side lateral flexion, 637 of right lateral flexion, 607 of left lateral flexion, 2170 of side-to-side rotation, 2152 of right rotation and 2122 of left rotation. (4) Conclusions: All collected and analyzed measurements of physiological movements of the dorsal spine had very disparate results from each other, the cause of the reason for such analysis is that the measurement protocols of the different types of measurement tools used in these measurements are different and cause measurement biases. To solve this, it is proposed to establish a standardized measurement protocol for all tools.

Evaluation of the effectiveness of the short-segment thoracolumbar instrumentation

Journal of Comprehensive Surgery, 2023

Aims: This prospective study aimed to compare the long-term follow-up findings of patients with short-segment thoracolumbar instrumentation with the long-term follow-up findings results of patients with long-segment thoracolumbar instrumentation. Methods: Patients who underwent surgery for a thoracolumbar junction spine fracture were included in this study. The patient's age, gender, and neurological impairment, "AOSpine Classification Scale", "Visual Analog Scale (VAS)", "modified Japanese Orthopedic Association (mJOA)" and "Oswestry Disability Index (ODI)" scores, pedicle and/or pars interarticularis fractures, anterior, middle, and posterior height loss of the fractured vertebral body (mm), the height loss rate of the fractured vertebra, angulation degree, sagittal and axial spinal canal diameters (mm) and presence of bone fragment extending into the spinal canal on CT images were recorded at admission to the hospital, and the end of the sixth month after surgical intervention. Duration of anesthesia and surgery time, the amount of bleeding during the surgery, the radiation level (mGy) released by fluoroscopy, performing laminectomy, length of stay in the intensive care unit, and hospital were recorded. Additionally, the stability and integrity of the instrumentation were examined with dynamic X-ray images. Results: Preoperative fractured vertebra collapse rates (t=4.175, p=0.001) and surgery times (t=4.175, p=0.001) were different between groups. In the long-segment group, preoperative VAS scores (Z=-2.687, p=0.007), mJOA scores (Z=-2.585, p=0.010), and ODI scores (t=53.253, p<0.001) were different from postoperative long-term follow-up values. In addition, in the short segment group, preoperative VAS scores (Z=-2.214, p=0.027), mJOA scores (Z=-2.333, p=0.020), and ODI scores (t=48.338, p<0.001) were different from the postoperative long-term follow-up values. ROC-curve analysis and Logistic Regression analysis results revealed that any study parameter could not predict the decision-making for inserting screws into the fractured vertebra, the need for laminectomy, the risk of developing postoperative instability, or the worse prognosis risk of mJOA. Conclusion: This study's results showed that short-segment instrumentation, which is performed by inserting a screw into the fractured vertebra, is as effective as long-segment instrumentation in providing both clinical and radiological improvement in patients. At the same time, it has advantages such as less operating time, less surgical bleeding, and short anesthesia time. However, it was determined that no parameter of the study could predict the placement of screws in the fractured spine, the need for laminectomy, the risk of postoperative instability, or the prognosis risk of mJOA. Therefore, it was concluded that conducting this study on a larger patient population would be appropriate.

Thoracoscopic approach for spine deformities

Journal of the American College of Surgeons, 2003

BACKGROUND: We reviewed our experience using anterior thoracoscopic procedures in the correction of severe idiopathic scoliosis and kyphotic deformities to evaluate the feasibility and effectiveness of such procedures. STUDY DESIGN: Twenty-four patients who underwent thoracoscopic surgical correction of the spine between March 1995 and December 2001 were retrospectively reviewed. A team consisting of one orthopaedic surgeon and one thoracic surgeon performed anterior thoracoscopic soft tissue release, disc excision, and bone grafting followed on the same day with posterior instrumentation and correction of deformity. RESULTS: There were 16 female and 8 male patients, with a median age of 16 years (range 11 to 47 years) with idiopathic scoliosis (20 patients) or kyphotic deformity (4 patients). The average time for the thoracoscopy was 125 minutes (range 60 to 175 minutes). Blood loss averaged 135 mL (range 20 to 350 mL), and a median number of five discs (range two to eight) were excised. The median ICU time was 2 days (range 1 to 8 days), and the median length of hospital stay was 6 days (range 4 to 11 days). One patient required conversion to an open procedure because of arterial bleeding from the cancellous bone (T5). Postoperative complications occurred in four patients (atelectasis, pneumothorax, pneumonia, and wound infection in one patient each). All patients had an uneventful hospital course after treatment. CONCLUSIONS: Thoracoscopic anterior procedures can be used safely and effectively in the treatment of idiopathic scoliosis and kyphotic deformity. This minimally invasive approach might decrease procedure-related trauma, operative time, blood loss, and length of hospitalization and may also alleviate postthoracotomy pain.

Biomechanical evaluation of a new fixation device for the thoracic spine

European Spine Journal, 2009

The technology used in surgery for spinal deformity has progressed rapidly in recent years. Commonly used fixation techniques may include monofilament wires, sublaminar wires and cables, and pedicle screws. Unfortunately, neurological complications can occur with all of these, compromising the patients' health and quality of life. Recently, an alternative fixation technique using a metal clamp and polyester belt was developed to replace hooks and sublaminar wiring in scoliosis surgery. The goal of this study was to compare the pull-out strength of this new construct with sublaminar wiring, laminar hooks and pedicle screws. Forty thoracic vertebrae from five fresh frozen human thoracic spines (T5-12) were divided into five groups (8 per group), such that BMD values, pedicle diameter, and vertebral levels were equally distributed. They were then potted in polymethylmethacrylate and anchored with metal screws and polyethylene bands. One of five fixation methods was applied to the right side of the vertebra in each group: Pedicle screw, sublaminar belt with clamp, figure-8 belt with clamp, sublaminar wire, or laminar hook. Pull-out strength was then assessed using a custom jig in a servohydraulic tester. The mean failure load of the pedicle screw group was significantly larger than that of the figure-8 clamp (P = 0.001), sublaminar belt (0.0172), and sublaminar wire groups (P = 0.04) with no significant difference in pull-out strength between the latter three constructs. The most common mode of failure was the fracture of the pedicle. BMD was significantly correlated with failure load only in the figure-8 clamp and pedicle screw constructs. Only the pedicle screw had a statistically significant higher failure load than the sublaminar clamp. The sublaminar method of applying the belt and clamp device was superior to the figure-8 method. The sublaminar belt and clamp construct compared favorably to the traditional methods of sublaminar wires and laminar hooks, and should be considered as an alternative fixation device in the thoracic spine. Keywords Thoracic vertebrae Á Scoliosis Á Orthopedic fixation devices Á Biomechanics All work performed at Mayo Clinic Rochester.

Principles of Spine Instrumentation

2020

Introduction : Spinal implants were initially, and are still, used for the supplementation of bony fusion. However, bony fusion operations were initially performed without implants.1 In the US, Wire and screw fixation of the unstable spine techniques remained to use until the pre-World War II years. 20 years after World War II, there were two major breakthroughs in spine surgery: the Harrington system for spine stabilization and deformity correction and the interspinous wiring technique of Rogers. Rogers described the technique of cervical interspinous wiring in the early 1940s. Harrington introduced his instrumentation system in 1962. Discussion : Since then, modifications of both techniques have been devised to increase their security of fixation. The next significant advance in dorsal spinal stabilization was the development of multisegmental spinal instrumentation. Multisegmental instrumentation permits sharing of the load applied to the instrumentation construct with multiple v...

The Treatment of Unstable Thoracic Spine Fractures with Transpedicular Screw Instrumentation: A 3-Year Consecutive Series

Spine, 2002

Study Design. The treatment of unstable thoracic spine fractures remains controversial. Theoretical biomechanical advantages of transpedicular screw fixation include three-column control of vertebral segments and fixation of a vertebral segment in the absence of intact posterior elements. Additionally, pedicle screw constructs may obviate the need for neural canal dissection and potential neural element impingement by intracanal instrumentation. A 3-year consecutive series was performed to evaluate the use of transpedicular screw fixation in the treatment of unstable thoracic spine injuries. Objective. This study was performed to evaluate the efficacy of transpedicular screw fixation in the upper, middle, and lower thoracic spine. Summary of Background Data. The use of rod/hook and rod/wiring techniques has been evaluated in the treatment of thoracic spine injuries. To date, a study evaluating the safety and efficacy of pedicle screw instrumentation in the upper, middle, and lower thoracic spine has not been reported. Methods. Thirty-two patients with 79 individual vertebral injury levels (T2-L1) treated with transpedicular spinal stabilization and bone fusion were evaluated during a 3-year consecutive series from 1998 to 2001. Patient charts, operative reports, preoperative and postoperative radiographs, computed tomography scans, and postoperative follow-up examinations and radiographs were reviewed from the time of surgery to final follow-up assessment. Radiographic measurements included: sagittal index, Gardner segmental kyphotic deformity, and compression percentage. Results. A total of 252 pedicle screws were placed, of which 222 were placed in segments T2-L1. Clinical examination and plain radiographs were used to determine the presence of a solid fusion. Fracture healing and radiographic stabilization occurred at an average of 4.8 months after the initial operation. There were no reported cases of hardware failure, loss of reduction, or painful hardware removal. Two hundred fifty-two transpedicular screws This study was performed to evaluate the use of transpedicular screw fixation in the upper, middle, and lower thoracic spine. We present our 3-year consecutive prospective experience of long and short segment transpedicular fixation of 32 unstable thoracic injuries. Methods Design. Over a 3-year consecutive period from 1998 to 2001, all patients with unstable thoracic (T2-L1) spinal injuries and adequately sized pedicles were treated using pedicle screw in-From

Radiographic Evaluation of Minimally Invasive Instrumentation and Fusion for Treating Unstable Spinal Column Injuries

Global Spine Journal, 2019

Study Design: Retrospective cohort. Objective: Facet fusion in minimally invasive spine surgery (MISS) may reduce morbidity and promote long-term construct stability. The study compares the maintenance of correction of thoracolumbar (TL) trauma patients who underwent MISS with facet fusion (FF) and without facet fusion (WOFF) and evaluates instrumentation loosening and failure. Methods: TL trauma patients who underwent MISS between 2006 and 2013 were identified and stratified into FF and WOFF groups. To evaluate progressive kyphosis and loss of correction, Cobb angles were measured at immediate postoperative, short-term, and long-term follow-up. Evidence of >2 mm of radiolucency on radiographs indicated screw loosening. If instrumentation was removed, postremoval kyphosis angle was obtained. Results: Of the 80 patients, 24 were in FF and 56 were in WOFF group. Between immediate postoperative and short-term follow-up, kyphosis angle changed by 4.0° (standard error [SE] 1.3°) in th...