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Tarik alp sargut, nils hecht, ran xu, georg bohner, marcus czabanka, julia stein, marcus richter, simon bayerl, johannes woitzik, peter vajkoczy: intraoperative imaging and navigated spinopelvic instrumentation: s2-alar-iliac screws combined with tricortical s1 pe dicle screw fixation: https://doi.Org/10.1007/s00586-022-0726.Patient age: mean age of 66 years (range 52 to 80 years).This value is the average age of the patients reported in the article as specific patients could not be identified.Patient sex: 37 females and 24 male patients.This value reflects the gender of the majority of the patients reported in the article as specific patients could not be identified.Date that the article was published for as the event dates were not provided in the published literature.Product identifiers are unknown.510(k)# is unknown.Neither the device nor films of applicable imaging studies were returned to the manufacturer for evaluation.Therefore, we are unable to determine the definitive cause of the reported event.Medtronic is submitting this report to comply with fda reporting regulations under 21 cfr parts 4 and 803.This report is based upon information obtained by medtronic, which the company may not have been able to fully investigate or verify prior to the date the report was required by the fda.Medtronic has made reasonable efforts to obtain more complete information and has provided as much relevant information as is available to the company as of the submission date of this report.This report does not constitute an admission or a conclusion by fda, medtronic, or its employees that the device, medtronic, or its employee caused or contributed to the event described in the report.In particular, this report does not constitute an admission by anyone that the product described in this report has any ¿defects¿ or has ¿malfunctioned¿.These words are included in the fda 3500a form and are fixed items for selection created by the fda to categorize the type of event solely for the purpose of regulatory reporting.Medtronic objects to the use of these words and others like them because of the lack of definition and the connotations implied by these terms.This statement should be included with any information or report disclosed to the public under the freedom of information act.Any required fields that are unpopulated are blank because the information is currently unknown or unavailable.A good faith effort will be made to obtain the applicable information relevant to the report.If information is provided in the future, a supplemental report will be issued.
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Tarik alp sargut, nils hecht, ran xu, georg bohner, marcus czabanka, julia stein, marcus richter, simon bayerl, johannes woitzik, peter vajkoczy: intraoperative imaging and navigated spinopelvic instrumentation: s2-alar-iliac screws combined with tricortical s1 p edicle screw fixation: https://doi.Org/10.1007/s00586-022-0726.Summary: the study was approved by the ethics committee (ea4/093/13) and included 61 consecutive patients (37 women, 24 men) undergoing navigated intraoperative ct based spinopelvic stabilization in our department between january 2016 and september 2019.The present study aimed to assess the feasibility, safety and accuracy of navigated spinopelvic fixation with focus on s2-alar-iliac screws (s2ais) and tricortical s1 pedicle screw implantation with the use of high-resolution three-dimensional intraoperative imaging and real-time spinal navigation.Patients undergoing navigated intraoperative ct-based spinopelvic stabilization between january 2016 and september 2019 were included.Pelvic fixation was achieved by implantation of s2ais or iliac screws (is).S1 screws were implanted with the goal of achieving tricortical purchase.In all cases, instrumentation was performed with real-time spinal navigation and intraoperative screw positioning was assessed using intraoperative computed tomography (ict), cone-beam ct (cbct) and robotic cone-beam ct (rcbct).Screw accuracy was evaluated based on radiographic criteria.To identify predictors of complications, univariate analysis was performed.Patients were positioned on radiolucent carbon-fiber operating tables and a midline exposure was performed.For acquisition of the spinal navigation scan with automatic patient / image co-registration, a spinal reference clamp (brainlab ag, munich, germany or medtronic plc, dublin, ireland) was attached to a spinous process or the iliac crest.All imaging was performed during apnea following 3¿5 min of preoxygenation.After image acquisition, navigated iliac instrumentation was performed first: depending on the type of iliac screw, the screw entry point was identified at the posterior iliac crest (is) or at the level of s2 between the s1 and s2 foramen (s2ais) under consideration of axial, coronal and sagittal in-line views.A pilot hole was drilled with a navigated drill guide and a trajectory was planned targeting the anterior inferior iliac spine.For s2ais instrumentation, the entry point was 2¿4 mm lateral between the s1 and s2 dorsal foramen.After drilling to a depth across the cortical bone of the sacro-iliac (si) joint, a guide-wire was inserted and the pilot hole was tappedto a desired depth across the si joint.It is important to note that there is a very specific feel when penetrating through the cortex of the si joint with a difference in tactile sensation when passing through the cance llous bone of the sacrum and going through the cortex of the si joint and into the cancellous channel of the iliac bone.For is insertion, the entry point was identified at the posterior superior iliac spine.Bone around the screw entry point was resected with a r ongeur to better accommodate the screw head.A navigated pilot hole was drilled targeting the anterior inferior iliac spine and a guide-wire was inserted for tapping of the cancellous iliac bone.For s2ais and is insertion, the tapped hole was probed for breaches and a cannulated, measured iliac screw (cd horizon® solera¿ spinal system, medtronic, dublin, ireland) with a length between 100 and 110 mm and diameter between 9.5 and 10.5 mm was inserted over the guide wire with the intention not to breach the iliac cortex.In s2ais insertion, the screw entry point caudal and just slightly medial to the entry point of the s1 screw permitted a direct rod connection.In is insertion, rod connection required the use of a separate connector.Next, tricortical s1 instrumentation was performed.To permit sufficient convergence of the screw trajectory required for purchase at the anterior and superior promontory, s1 screws were inserted through a parafascial, transmuscular approach.After parafascial incision, an entry point slightly lateral and caudal to the posterior s1 pedicle cortex was identified with a navigated drill-guide and a pilot hole was drilled targeting the superior and anterior promontory.Identification of the entry point and trajectory was performed in axial, coronal and sagittal in-line views.After drilling of the pilot hole, the pedicle was tapped and screw measuring 7.5¿9.5 mm in diameter and 50¿55 mm length (cd horizon® solera¿ spinal system, medtronic, dublin, ireland) was inserted with intention to breach the anterior and superior cortex of the promontory.Misalignment was judged by the primary surgeon and included: (a) lateral, medial or anterior breach of s2ais or is during passage through the cancellous iliac bone, (b) failure of si joint passage in s2ais, and c) lateral, medial, cranial or caudal breach of the s1 pedicle > 4 mm, a direct intraoperative navigated screw revision was performed, followed by a final ict/cbct/rcbct control scan to confirm repositioning.Importantly, failure to achieve tricortical s1 purchase with anterior and superior breach due to an insufficient convergence of the screw trajectory was not per se considered a reason for revision.In both groups, the majority of patients had a history of lumbosacral surgery or fusion, respectively (71 and 54% for s2ais; 89 and 67% for is).Twenty-three out of 61 patients (38%) underwent correction of kyphotic deformity and sagittal imbalance with pedicle subtraction osteotomy.Intraoperative imaging and spinal navigation were performed with ict in 34 patients, cbct in 21 patients and rcbct in six patients.Reported events: 1.During the early perioperative course, a medially misplaced s2ais resulted in vascular injury requiring endovascular intervention in one patient.2.One patient suffered extensive pulmonary embolism and died due to misplaced screw.3.12 patients underwent re-operation as an additional procedure for surgical site infection, hematoma, csf fistula due to misplaced screw.4.In one patient, bilateral misalignment was observed, resulting in a successful revision and 9 patients had underwent intraoperative correction of iliac screws due to misalignment.5.One patient required intraoperative correction of an s1 screw due to a lateral pedicle breach > 4 mm.
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