Placement Of Instrumentation Research Articles

Novel Applications of Spinal Navigation in Deformity and Oncology Surgery-Beyond Screw Placement.

Computer-assisted navigation has made a major impact on spine surgery, providing surgeons with technological tools to safely place instrumentation anywhere in the spinal column. With advances in intraoperative image acquisition, registration, and processing, many surgeons are now using navigation in their practices. The incorporation of navigation into the workflow of surgeons continues to expand with the evolution of minimally invasive techniques and robotic surgery. While numerous investigators have demonstrated the benefit of navigation for improving the accuracy of instrumentation, few have reported applying this technology to other aspects of spine surgery. Surgeries to correct spinal deformities and resect spinal tumors are technically demanding, incorporating a wide range of techniques not only for instrumentation placement but also for osteotomy planning and executing the goals of surgery. Although these subspecialties vary in their objectives, they share similar challenges with potentially high complications, invasiveness, and consequences of failed execution. Herein, we highlight the utility of using spinal navigation for applications beyond screw placement: specifically, for planning and executing osteotomies and guiding the extent of tumor resection. A narrative review of the work that has been done is supplemented with illustrative cases demonstrating these applications.

Development of a fluoroscopically guided robotic assistant for instrument placement in pelvic trauma surgery.

Purpose: A method for fluoroscopic guidance of a robotic assistant is presented for instrument placement in pelvic trauma surgery. The solution uses fluoroscopic images acquired in standard clinical workflow and helps avoid repeat fluoroscopy commonly performed during implant guidance. Approach: Images acquired from a mobile C-arm are used to perform 3D-2D registration of both the patient (via patient CT) and the robot (via CAD model of a surgical instrument attached to its end effector, e.g; a drill guide), guiding the robot to target trajectories defined in the patient CT. The proposed approach avoids C-arm gantry motion, instead manipulating the robot to acquire disparate views of the instrument. Phantom and cadaver studies were performed to determine operating parameters and assess the accuracy of the proposed approach in aligning a standard drill guide instrument. Results: The proposed approach achieved average drill guide tip placement accuracy of and angular alignment of in phantom studies. The errors remained within 2mm and 1deg in cadaver experiments, comparable to the margins of errors provided by surgical trackers (but operating without the need for external tracking). Conclusions: By operating at a fixed fluoroscopic perspective and eliminating the need for encoded C-arm gantry movement, the proposed approach simplifies and expedites the registration of image-guided robotic assistants and can be used with simple, non-calibrated, non-encoded, and non-isocentric C-arm systems to accurately guide a robotic device in a manner that is compatible with the surgical workflow.

Ex-vivo forces associated with intrauterine device placement and perforation: a biomechanical evaluation of hysterectomy specimens

BackgroundThis biomechanical analysis of hysterectomy specimens assesses the forces associated with intrauterine device placement. These include compressive forces required to cause uterine perforation with two commonly available commercial intrauterine device placement instruments and a metal uterine sound.MethodsWe obtained hysterectomy specimens at a single academic center. All specimens resulted from excision for benign conditions in premenopausal women by any operative method. Within one hour of excision, we stabilized uterine specimens in an apparatus specifically designed for this analysis. A single, experienced clinician performed all experimental maneuvers and measured forces with a Wagner FDIX-25 force gauge. The investigator applied traction on a tenaculum to approximate force used during an intrauterine device placement. The maximum compressive force to the uterine fundus was determined by using manufacturers’ placement instruments for two commercially available products and a metal sound.ResultsSixteen individuals provided hysterectomy specimens. No complete perforations occurred while using loaded intrauterine devices; in a single observation the LNG IUS entered the myometrium. The plastic intrauterine device placement rod bowed in all attempts and did not perforate the uterine serosa at the fundus. A metal uterine sound created a complete perforation in all specimens (p < .001). The lowest mean maximum force generated occurred with the levonorgestrel intrauterine system placement instrument 12.3 N (SD ± 3.8 N), followed by the copper T380A intrauterine device placement instrument 14.1 N (SD ± 4.0 N), and highest for the metal sound 17.9 N (SD ± 7.6 N) (p < 0.01).ConclusionsIn this ex-vivo model, metal uterine sounds caused complete perforation and intrauterine device placement instruments did not.This study received Institutional Review Board (IRB0059096) approval.

The Comparison of Balloon and Camera Dissection of the Preperitoneal Space in Totally Extraperitoneal Repair Hernia Repair. Our Initial Experience!

Purpose. To perform totally extraperitoneal repair of a hernia, it is essential to create a working space for the placement of instruments. In this study, we aimed to compare balloon dissection (BD) and camera or telescopic dissection (CD) with respect to the surgical outcomes, without considering the cost-effectiveness. Methods. Forty consecutive, healthy, unilateral inguinal hernia patients who underwent Totally Extraperitoneal Repair hernia repair were randomized into 2 groups according to whether they received BD or CD. The perioperative demographic characteristics were recorded. All the operations were video recorded from the beginning to the end of each procedure. The virtually constructed periods of the procedures were evaluated by another surgeon who watched each video. The time spent for each period, the severity score assigned by the surgeon, the total operation time, the peritoneal laceration rate, the presence of early and late postoperative pain, the number of postoperative visits, the total analgesic requirements, and the complications were recorded. Results. The demographic properties of the patients, the perioperative and postoperative complications, and the severity scores in the BD and CD groups were statistically similar. The total operating time and the time from the dissection of the peritoneum to the reduction of the hernia sac were significantly longer in the CD group. Post-discharge analgesic consumption, Visual Analog Scale scores, and the number of visits were similar between the groups. Conclusions. The dissection of the working space in the preperitoneal area can be achieved using camera dissection without the risk of common complications associated with balloon dissection, particularly balloon rupture.

Safety of Laparoscopy in Patients with Ventriculoperitoneal Shunts

The relationship between the intra-abdominal pressure (IAP) and intracranial pressure (ICP) has been suspected for more than 100 years and was subsequently confirmed by numerous studies in both animals and humans which demonstrate the link and the positive correlation between IAP and ICP. There are mounting concerns that the pneumoperitoneum created during laparoscopic surgery to create space for instrument placement and to allow safe tissue dissection may result in an increase in the ICP secondary to the increase in the IAP which may result in serious consequences in patients with Ventriculoperitoneal (VP) shunts. There is uncertainty about the safety of laparoscopic surgery in VP shunt patients. The aim of this article is to review the literature to answer the question [Is laparoscopic surgery safe in VP shunt patients with and without intraoperative monitoring of ICP]?

Fluoroscopic Guidance of a Surgical Robot: Pre-clinical Evaluation in Pelvic Guidewire Placement.

A method and prototype for a fluoroscopically-guided surgical robot is reported for assisting pelvic fracture fixation. The approach extends the compatibility of existing guidance methods with C-arms that are in mainstream use (without prior geometric calibration) using an online calibration of the C-arm geometry automated via registration to patient anatomy. We report the first preclinical studies of this method in cadaver for evaluation of geometric accuracy. The robot is placed over the patient within the imaging field-of-view and radiographs are acquired as the robot rotates an attached instrument. The radiographs are then used to perform an online geometric calibration via 3D-2D image registration, which solves for the intrinsic and extrinsic parameters of the C-arm imaging system with respect to the patient. The solved projective geometry is then be used to register the robot to the patient and drive the robot to planned trajectories. This method is applied to a robotic system consisting of a drill guide instrument for guidewire placement and evaluated in experiments using a cadaver specimen. Robotic drill guide alignment to trajectories defined in the cadaver pelvis were accurate within 2 mm and 1° (on average) using the calibration-free approach. Conformance of trajectories within bone corridors was confirmed in cadaver by extrapolating the aligned drill guide trajectory into the cadaver pelvis. This study demonstrates the accuracy of image-guided robotic positioning without prior calibration of the C-arm gantry, facilitating the use of surgical robots with simpler imaging devices that cannot establish or maintain an offline calibration. Future work includes testing of the system in a clinical setting with trained orthopaedic surgeons and residents.

Soft-Tissue Management and Neurovascular Protection During Opening-Wedge High Tibial Osteotomy

Medial opening-wedge high tibial osteotomy (OW-HTO) is an excellent surgical option for patients with varus knee osteoarthritis. Medial collateral ligament (MCL) release and posterior neurovascular structure protection during OW-HTO are steps that often induce stress and nervousness during surgery, especially for surgeons in the earlier stages of their learning curve. While is it well-known that the MCL should be released during OW-HTO, the standard retraction techniques pose challenges in visualization and instrument placement in the surgical field. We present our technique, which illustrates an alternative method to manage the MCL and safely protect the neurovascular structures using a second and more posterior surgical window during OW-HTO.

Analysis of the difference in pulse oxygen saturation between the ventral and dorsal fingers.

This study aimed to investigate the effect of different probe placements on the ventral and dorsal sides of the same finger using pulse oxygen saturation monitoring. This clinical trial used a convenience sampling method in patients admitted to the Second Hospital of Hebei Medical University. We enrolled 1330 patients from March to July 2018, including patients who were hospitalized in the intensive care unit (n=258) and in the general ward (n=1072). Pulse oxygen saturation measurements obtained from the ventral and dorsal sides of the same finger were compared. This work adhered to the STROBE checklist requirements. We found that pulse oxygen saturation measurements between the dorsal and ventral sides of a finger were not affected by different fingers, disease types, the application of a ventilator, vasoactive drugs, the conscious state of the patient or the instrument model. Our findings suggested no significant difference in saturation measurements with variation in the placement of the pulse oxygen saturation measurement instrument between the dorsal and ventral sides of a finger, regardless of illness severity. We believe that these results could simplify the monitoring procedures performed by nurses and eliminate worries concerning the inaccuracy of data because of varied probe positions.

Percutaneous lumbopelvic fixation

Fixation into the ilium has traditionally been performed for scoliosis. The technique has evolved greatly from open highly invasive techniques with elevation of flaps from the pelvis and placement of contoured rods passed between the inner and outer cortices of the ilium, to open techniques involving iliac bolts and transverse connectors.1–3 Indications have expanded to include stabilization in complex pelvic tumors and for complex trauma.4–7 Modern techniques involving entirely percutaneous placement of pelvic instrumentation with subfascial passing of rods into lumbar pedicle screws are the most recent evolution of the technique of fixation to the pelvis.5,8 This article reviews current concepts for minimally invasive percutaneous lumbopelvic fixation and presents illustrative examples .

Current innovation in virtual and augmented reality in spine surgery.

In spinal surgery, outcomes are directly related both to patient and procedure selection, as well as the accuracy and precision of instrumentation placed. Poorly placed instrumentation can lead to spinal cord, nerve root or vascular injury. Traditionally, spine surgery was performed by open methods and placement of instrumentation under direct visualization. However, minimally invasive surgery (MIS) has seen substantial advances in spine, with an ever-increasing range of indications and procedures. For these reasons, novel methods to visualize anatomy and precisely guide surgery, such as intraoperative navigation, are extremely useful in this field. In this review, we present the recent advances and innovations utilizing simulation methods in spine surgery. The application of these techniques is still relatively new, however quickly being integrated in and outside the operating room. These include virtual reality (VR) (where the entire simulation is virtual), mixed reality (MR) (a combination of virtual and physical components), and augmented reality (AR) (the superimposition of a virtual component onto physical reality). VR and MR have primarily found applications in a teaching and preparatory role, while AR is mainly applied in hands-on surgical settings. The present review attempts to provide an overview of the latest advances and applications of these methods in the neurosurgical spine setting.

Using Predictive Analytics to Track Students: Evidence from a Seven-College Experiment

Tracking is widespread in U.S. education. In post-secondary education alone, at least 71% of colleges use a test to track students. However, there are concerns that the most frequently used college placement exams lack validity and reliability, and unnecessarily place students from under-represented groups into remedial courses. While recent research has shown that tracking can have positive effects on student learning, inaccurate placement has consequences: students face misaligned curricula and must pay tuition for remedial courses that do not bear credits toward graduation. We develop an alternative system to place students that uses predictive analytics to combine multiple measures into a placement instrument. Compared to colleges’ existing placement tests, the algorithm is more predictive of future performance. We then conduct an experiment across seven colleges to evaluate the algorithm’s effects on students. Placement rates into college-level courses increased substantially without reducing pass rates. Adjusting for multiple testing, algorithmic placement generally, though not always, narrowed gaps in college placement rates and remedial course taking across demographic groups. A detailed cost analysis shows that the algorithmic placement system is socially efficient: it saves costs for students while increasing college credits earned, which more than offsets increased costs for colleges. Costs could be reduced with improved data digitization, as opposed to entering data by hand.

Using Predictive Analytics to Track Students: Evidence from a Seven-College Experiment

Tracking is widespread in U.S. education. In post-secondary education alone, at least 71% of colleges use a test to track students. However, there are concerns that the most frequently used college placement exams lack validity and reliability, and unnecessarily place students from under-represented groups into remedial courses. While recent research has shown that tracking can have positive effects on student learning, inaccurate placement has consequences: students face misaligned curricula and must pay tuition for remedial courses that do not bear credits toward graduation. We develop an alternative system to place students that uses predictive analytics to combine multiple measures into a placement instrument. Compared to colleges'; existing placement tests, the algorithm is more predictive of future performance. We then conduct an experiment across seven colleges to evaluate the algorithm's effects on students. Placement rates into college-level courses increased substantially without reducing pass rates. Adjusting for multiple testing, algorithmic placement generally, though not always, narrowed gaps in college placement rates and remedial course taking across demographic groups. A detailed cost analysis shows that the algorithmic placement system is socially efficient: it saves costs for students while increasing college credits earned, which more than offsets increased costs for colleges. Costs could be reduced with improved data digitization as opposed to entering data by hand.

The instrument transfer method in four handed dentistry in dental operating microscope as a module of a training program in the aspect of reduction of the dynamic load of the visual system of the operator

Resume. Introduction of a Dental Operating Microscope (DOM) in the clinical work can make some difficulties in operator’s work.In particular, to ensure the safety of the operator’s visual system and ergonomics of the work, the operator’s gaze should be continuously directed to the operating field. The instruments should be moved over the operating field by the assisting personnel, whose participation in the transfer is not complete until the evening nstrument is visible through the microscope and the operator is fully capable of controlling its movement. Instrument transfer method in DOM includes 3 steps: modified direct placement, predelivery, delivery and exchange of instruments. In the presented method the most important elements are the properly oriented end of the instrument by dental assistant and mutual grasp of instrument. The method allows to reduce the load on the operator’s visual system and to make four-handed work ergonomic. Key words: dental operating microscope (DOM), four-handed dentistry in DOM, instrument transfer in DOM, mutual grasp, visual system overload of dental operator.

Fluoroscopy time analysis of a prospective, multi-centre study comparing robotic- and fluoroscopic-guided placement of percutaneous pedicle screw instrumentation for short segment minimally invasive lumbar fusion surgery.

As minimally invasive spine surgery becomes more widespread, concerns regarding radiation exposure to surgeons and patients alike have become a growing concern. Robotic guidance has been developed as a way to increase the accuracy of instrumentation while decreasing radiation burden. A retrospective analysis of a large, multi-centre, prospective study comparing robotic-guided (RG) to fluoroscopic-guided (FG) (Multi-centre, Partially Randomized, Controlled Trial of MIS Robotic vs. Freehand in Short Adult Degenerative Spinal Fusion Surgeries) was performed to evaluate for differences in radiation exposure between study groups. RG was associated with 78.3% (p<0.001) and 79.8% (p<0.001) reduction in total and per screw fluoroscopy times, respectively, as compared to FG. RG was also associated with a 50.8% (p<0.001) reduction in total operative fluoroscopy time. RG was associated with significantly lower fluoroscopy times compared to FG. This suggests that utilization of robotic navigation systems may result in decreased operative radiation exposure, which is a growing concern for surgeons performing minimally invasive spine surgery.

Ultrasound-Assisted Posterior Knee Arthroscopy: A Description of the Technique.

Entering the posterior knee with arthroscopy can be difficult. Scar tissue, a tumor, and the obese patient can make instrument placement difficult and risk iatrogenic injury. Ultrasound can be used to visualize the posterior knee and provide direct guidance of instrumentation. We describe the technique and indications for using ultrasound during arthroscopy. Accurate and atraumatic insertion of instruments can be performed with no damage to total knee components or the knee joint. Ultrasound guidance should be considered during difficult posterior knee arthroscopy.

Diagnostic and Therapeutic Elbow Arthroscopy Using Small-Bore Needle Arthroscopy

Needle arthroscopy may provide several potential advantages over standard arthroscopy. The smaller camera size and weight allows for a minimally invasive and percutaneous approach with decreased fluid use. As resolution and image quality improve, the potential to expand clinical use for therapeutic applications becomes possible. One promising use is in elbow arthroscopy. Difference in the technology, such as a zero-degree optic and less-rigid instrumentation, necessitate a modified technique to accommodate thorough diagnostic arthroscopy and therapeutic procedures. This manuscript introduces the authors' approach to diagnostic needle arthroscopy of the anterior and posterior elbow compartments and placement of therapeutic instrumentation. This technique could theoretically decrease the risk of iatrogenic neurovascular injuries, reduce postoperative swelling and pain due to decreased fluid use, and potentially lead to faster recovery.

Agility and Assessment in the Age of COVID‐19: How Fast Can a Community College Dance?

Agility and Assessment in the Age of COVID‐19: How Fast Can a Community College Dance?

Perioperative infection prevention strategies for double-lung transplantation in elderly patients with COVID-19

To summarize the experience of perioperative prevention during double-lung transplantation for elderly patients with coronavirus disease 2019 (COVID-19). Clinical data of 2 elderly patients with COVID-19 who underwent double-lung transplantation in the First Affiliated Hospital of Zhejiang University School of Medicine in March 2020 were retrospectively reviewed. Perioperative protective measures were introduced in terms of medical staffing, respiratory tract, pressure injuries, air in operating room, instruments and equipment, pathological specimens, and information management. Two cases of double-lung transplantation were successfully completed, and the patients had no operation-related complications. Extracorporeal membrane oxygenator was successfully removed 2 to 4 days after surgery and the patients recovered well. There was no infection among medical staff. Adequate preoperative preparation, complete patient transfer procedures, proper placement of instruments and equipment, strengthening of intraoperative care management, and attention to prevention of pressure injury complications can maximize the safety of COVID-19 patients and medical staff.

Mazor X Stealth Robotic Technology: A Technical Note

Minimally invasive techniques in spine surgery have continued to advance as robotic technology has evolved over several generations. Although traditional techniques for placing pedicle screws are still widespread in practice, newer technology has increased the reliability of accurately placing instrumentation with smaller incisions and subsequent decreased length of stay. Additionally, advancements in planning software have improved the ability to align posterior instrumentation to assist with rod placement on multilevel constructs. This paper describes the surgical techniques and operative workflow for placing pedicle screws with the latest robotic technology. The robotic platform, registration, surgical planning, and placement of instrumentation are discussed in detail. Advantages of the Mazor X Stealth Edition compared with the previous generation robot include obviating the need for K wires and eliminating the need for a percutaneous pin, as navigation is integrated into the robot. Our use of this new technology has been encouraging. Using the techniques described in this paper, the first 90 pedicle screws placed with the Mazor X Stealth Edition robot yielded 100% grade A accuracy on the Gertzbein-Robbins scale confirmed on immediate postoperative CT. There were no complications experienced in any case. In our experience, this robotic technology has the potential to improve patient outcomes and is associated with advanced surgical planning compared with more traditional techniques.

The Anatomical Course of the Superior Gluteal Nerve With Regard to the Direct Anterior Approach for Primary and Revision Total Hip Arthroplasty

BackgroundDuring primary and revision total hip arthroplasty (THA) lesions of the superior gluteal nerve (SGN) can substantially compromise patient outcome. For the primary direct anterior approach (DAA) and its proximal approach extensions, especially the muscular branch entering the tensor fasciae latae (TFL) muscle is at risk. SGN lesions can result in fatty atrophy and functional loss of the TFL. Therefore, the course and branching pattern of the SGN were examined and related to the DAA and its proximal approach extension. The aim of the study is to describe safe and danger zones for the SGN with regard to the DAA and its proximal extensions. MethodsTwenty-five formalin-fixed cadavers with 48 hemipelves were dissected. The course, distribution, and branching pattern of the SGN and its muscular branch inserting into the TFL muscle were investigated with regard to the DAA with the help of anatomical landmarks like the greater trochanter and the iliac tubercle. ResultsIn 72.9% of the specimens the SGN passed the greater sciatic foramen superior to the piriformis muscle with one main trunk. The muscular branch of the SGN supplying the TFL divided from the main branch in 89.6% of the specimens at the level of the greater sciatic foramen. Before entering the TFL muscle the muscular branch showed a variable branching pattern in the interval between the gluteus medius and minimus. A danger zone for the SGN with regard to the DAA was found in the proximal fourth of the skin incision. ConclusionSpecial care in proximal instrument placement should be taken during the DAA. When extending the DAA proximally manipulations in the proximal, caudal surgical window should be performed with the utmost care.