Pedicle screw instrumentation and spinal deformities: have we gone too far? (original) (raw)
Related papers
Thoracic pedicle screw fixation for spinal deformity
Neurosurgical FOCUS, 2003
Techniques to improve segmental fixation have advanced the ability to correct complex spinal deformity. The purpose of instrumentation is to correct spinal deformity or to stabilize the spine to enhance the long-term biological fusion. The ultimate goal of spinal deformity surgery is the creation of a stable, balanced, pain-free spine centered over the pelvis in the coronal and sagittal planes. The minimum number of segments should be fused. These concepts remain challenging in the setting of deformity and instability. Successful results can be obtained if the surgeon understands the technology available, its capabilities, biological limitations, and the desired solution. The authors prefer to use thoracic pedicle screws when treating patients with spinal deformity because they provide greater corrective forces for realignment. This allows shorter-segment constructs and the possibility of true derotation in correction. In this article the authors focus on the use of thoracic transpe...
IOSR Journal of Dental and Medical Sciences, 2016
Transpedicular stabilization has become an established method for instrumentation of the thoracic and lumbar spine because of its immediate rigidity, better coronal and sagittal correction and shorter fusion length when compared to the other instrumentation techniques. Pedicle screw insertion resulting in neurologic deficit is rare, but may be due to faulty placement of the screw, with perforation of the cortex and impingement on adjacent neural structures. Despite improvements in the design of the instruments and attention to insertion techniques, cortical perforation does occur. Because many transgressions are asymptomatic, the true incidence is not known. Roy-Camille et al report in their experience 10% of screws were not completely in the pedicle. A retrospective study was done to determine the incidence of screw misplacement and complications in 120 transpedicular screws (30 patients) in the thoracolumbar spine with conventional open technique and intraoperative fluoroscopy. Outcome measures were: Accuracy of screw placement was evaluated by postoperative CT scan. Screw position was classified as 1.correct when the screw was completely surrounded by the pedicle cortex, 2. cortical breach and as 3. frank penetration when the screw was outside the pedicular boundaries. Frank penetration was further subdivided as grade A (up to 2.0 mm), grade B(2.1-4 mm), and grade C(> 4 mm).Results-In our study we found out that only 56 screws were in the category of correct, while a total of 40 pedicle screws had Frank penetration, mostly medially(followed by laterally and anteriorly) with a grade B penetration (followed by grade A and grade C) with 8 complications attributable to this misdirections, of which, 4 each had medial and lateral breech, all of which thankfully completely resolved with time at subsequent follow up.
Review of Spinal Pedicle Screws
The Egyptian Journal of Hospital Medicine, 2019
Background: Pedicle screws are medical implants which are implanted posteriorly into the vertebrae of the spine and longitudinally connected to a rod to form a construct which corrects spinal alignment or promotes stabilization. Pedicle screw fixation is considered to be the gold standard of spinal internal fixation due to its many benefits in a variety of debilitating spinal conditions. Objective: The aim of the work is to evaluate the use of spinal pedicle screws for different lesions in the past, in the present and in the future. Conclusion: Some successful applications of pedicle screws include surgical treatment of scoliosis reduction and stabilization of spondylolisthesis, stabilization of unstable spinal fractures, simple lumbar degenerative disc disease, primary or metastatic tumors of the lumbar spine, and surgical revision of symptomatic pseudoarthrodesis of the lumbar region.
The posterior pedicle screw construct: 5-year results for thoracolumbar and lumbar curves
Journal of Neurosurgery: Spine, 2013
Object Several studies of the outcomes of patients with adolescent idiopathic scoliosis (AIS) with thoracolumbar and lumbar curves after treatment with posterior pedicle screws have been reported, but most of these studies reported only 2-year follow-up. The authors analyzed the radiographic and clinical outcomes of patients with thoracolumbar and lumbar curves treated with posterior pedicle screws after 5 years of follow-up. Methods A multicenter database was retrospectively queried to identify patients with AIS who underwent spinal fusion for Lenke 3C, 5C, and 6C curves. Radiographs from the following times were compared: preoperative, first follow-up visit, 1-year follow-up visit, 2-year follow-up visit, and 5-year follow-up visit. Chart review included scoliometer measurements, Scoliosis Research Society (SRS)–22 questionnaires, and complications requiring return to the operating room. Results Among 26 patients with Lenke 3C, 5C, and 6C curves, the mean (± SD) age was 14.6 ± 2.1...
Accuracy of free hand technique of transpedicular screw fixation in correction of spinal deformities
International Journal of Orthopaedics Sciences, 2017
Introduction: Pedicular screw fixation is now the novel technique to correct spinal deformities. Navigation or CT guided systems are not easily available in Indian scenario. Free hand technique of pedicle screw insertion is commonly practiced for degenerative spine and traumatic spine with fluoroscopic guidance, but for deformed spine fluoroscopy may not be always helpful. AIM: we intend to evaluate accuracy and safety free hand technique in kyphoscoliotic spine. Material and Methods: Twenty consecutive patients suffering from kyphoscoliosis underwent posterior stabilization using a total of 260 titanium/stainless steel transpedicular screws. The position of the screws inserted into the deformed spine was evaluated by postoperative computed axial tomography (CAT) scans. All patients underwent 3-mm thin-section postoperative CT. Pedicle perforations were classified as either medial or lateral breech and distance was measured of breach. Results: Of the 260 screws inserted into the deformed scoliotic spine 27 screws showed moderate lateral cortical perforation whereas 11 screws showed moderate medial cortical breech. These screws showed cortical perforation in the range of 2.1-4.0mm.One screw each showed cortical breech in the range of 4.1-6.0mm on medial and lateral side. Conclusion: This study concludes that with good knowledge of anatomy of spine, free hand thoracic pedicle screw insertion technique for the surgical treatment of normal and deformed thoracic spines without any radiographic guidance and/or intraoperative tracking devices appears to be a safe, and reliable procedure.
Early complications of spinal pedicle screw
European Spine Journal, 1997
The complications of 648 consecutively inserted Universal AO pedicle screws (140 in the thoracic spine and 508 in the lumbar spine) performed by one surgical team to treat 91 patients with spinal problems, were reviewed. The spinal pathology consisted of: scoliosis (34 patients), degenerative lower lumbar spinal disease (25 patients), neoplastic spinal disease (11 patients), thoracic kyphosis (8 patients), spinal fractures (7 patients), lumbo-sacral spondylolisthesis (3 patients), and osteomyelitis (3 patients). Intraoperative complications were: screw misplacement (n = 3), nerve root impingement (n = 1), cerebrospinal fluid leak (n = 2) and pedicle fracture (n = 2). Postoperative complications were; deep wound infection (n = 4), screw loosening (n = 2) and rod-screw disconnection (n = 1). The conclusion was that pedicle screw fixation has an acceptable complication rate and neurological injury during this procedure is unlikely.
Asian spine journal, 2014
A retrospective cross-sectional study. The purpose of this study is to evaluate the accuracy and safety of free-hand pedicle screw insertion performed by a young surgeon. Few articles exist regarding the safety of the free-hand technique without inspection by an experienced spine surgeon. The index surgeon has performed spinal surgery for 2 years by himself. He performed fluoroscopy-assisted pedicle screw installation for his first year. Since then, he has used the free-hand technique. We retrospectively reviewed the records of all consecutive patients undergoing pedicle screw installation using the free-hand technique without fluoroscopy in the thoracic or lumbar spine by the index surgeon. Incidence and extent of cortical breach by misplaced pedicle screw was determined by a review of postoperative computed tomography (CT) images. A total of 36 patients received 306 free-hand placed pedicle screws in the thoracic or lumbar spine. A total of 12 screws (3.9%) were identified as brea...
Internal fixation of the spine in traumatic and scoliotic cases. The potential of pedicle screws
Technology and Health Care, 1996
Internal fixation techniques are in common used to stabilize vertebral fractures and correct severe scoliosis. Consolidation of injured vertebrae with neighbouring intact vertebra is the goal in the former case whilst fusion of the vertebrae in a corrected position is aimed at in the latter case. Degenerative spine diseases are not considered in this paper. Classical instrumentation consists of rods (e.g., Cotrel-Dubousset, Harrington, Luque-Galveston) attached to the bone by means of hooks or wires. More recently, transpedicular screws are introduced as an alternative bone/implant interface. Comparing the results of several studies, the posterior pedicle screw based devices demonstrate the ability to produce the most rigid constructs. However, the insertion of pedicle screws implicates a relatively high complication risk and its succes strongly depends on the experience of the surgeon. Incorrect drilled holes or malplacement of the screws can result in nerve root injuries and fracture of the pedicle. Studies reported complication ratios up to 30% with substantial neurological implications. A certain degree of automation of the critical actions may be necessary to enhance the safety of pedicle screw insertion. Two techniques of computer assisted spine surgery are compared. Both techniques permit a computer assisted surgical planning based on CT images. During operation the first system permanently observes the position of the drill relative to the spine and informs the surgeon on the deviation of the actual drill path to the planned drill path. The second system uses a pre-operative surgical planning to design and construct a mechanical drill guide, fitting perfectly on the patient's spine.
Mid-length Pedicle Screws in Posterior Instrumentation of Scoliosis
Asian Spine Journal
We determine the need for the use of mid-length pedicle screws (screws with 2.5-mm long increments) during posterior spinal instrumentation. Overview of Literature: Many biomechanical studies have been performed showing that increasing the pedicle screw insertion depth provides an improved resistance to pullout, cyclic loading, and derotational forces, but no intermediate length screws were used. Methods: We prospectively evaluated 120 patients who received posterior segmental instrumentation for structural scoliosis. Preoperatively, 91.44-cm long cassette anteroposterior (AP), lateral, and AP bending radiographs and multiplanar computed tomography were performed in all patients routinely. We measured chord length to determine the maximum probable screw length of all vertebrae. All pedicle screws were attempted to be placed as long as possible. The main intention was at least to engage the subcortical bone of the anterior vertebral cortex. Especially in the apical region, the screws were attempted to be inserted bicortically. The length, level, region, and side of each screw were recorded. Screws with 5-mm increments were called standard length screws (SLS), and middle-sized screws with 2.5-mm increments were called mid-length screws (MLS). Results: Of 2,846 pedicle screws inserted, 1,575 (55.4%) were SLS and 1,271 (44.6%) were MLS, demonstrating a need for MLS in scoliosis surgery (p<0.05). The need for MLS increased significantly in the thoracic region, apical vertebrae, and convex side (p<0.05). Conclusions: If anterior cortex engagement or longer placement of pedicle screws is intended during scoliosis surgery, for safer placement, screws with 2.5-mm increments should be available in posterior instrumentation systems.