Accuracy Of Placement Research Articles

A More Efficient and Safer Improved Percutaneous Pedicle Screw Insertion Technique-Trajectory DynamicAdjustment Technique, Technical Note, and Clinical Efficacy.

Percutaneous pedicle screw fixation (PPSF) technique requires a very precise entry point of the Jamshidi needle, which leads to repeated adjustments, damaging the pedicle and increasing radiation exposure. This study was designed to propose an improved percutaneous pedicle screw fixation technique-trajectory dynamic adjustment (TDA) technique, and evaluate its feasibility and assess the clinical outcomes. A total of 445 patients with lumbar spondylolisthesis or lumbar spinal stenosis associated with instability from June 2017 to May 2022 were included in the retrospective study. They were randomly separated into two groups. Two hundred thirty-one patients underwent TDA technique (TDA group). Two hundred fourteen patients underwent traditional PPSF technique (PPSF group). All patients underwent postoperative CT to assess the accuracy of screw placement, superior facet joint violation (FJV). The evaluated clinical outcomes were needle insertion time, radiation exposure, blood loss, hospital stay, the Japanese Orthopedic Association (JOA) score, the Visual Analogue Scale (VAS) scores for lower back pain (LBP), and leg pain, lumbar interbody fusion rate, and postoperative complications. The independent-sample t test and paired t-test were used for continuous data. The contingency table and Mann-Whitney U test were used for categorical data. The time of the insertion in TDA group was significantly lower than that in PPSF group (p < 0.05). Similarly, the fluoroscopy frequency in TDA group was significantly lower than that in PPSF group (p < 0.05). There was no difference in intraoperative blood loss and hospital stay between the two groups (p > 0.05). Overall, there was no significant difference in the proportion of clinically acceptable screws between the two groups (p > 0.05). In addition, the lateral screw misplacement in TDA group was higher. Moreover, FJV rate was significantly lower than that in PPSF group (p < 0.05). In both TDA group and PPSF group, postoperative back and leg pain and the JOA score were significantly improved (p < 0.05). However, there were no significant differences in the pre- and postoperative VAS score for back and leg pain and the JOA score, JOA recovery rate, intervertebral fusion rate, and complications rate between the two groups (p > 0.05). Compared to traditional PPSF technique, TDA technique is a safer and more effective procedure which has shorter surgical time, lower radiation exposure, and lower facet joint violation rate.

Exploring the Learning Curve of Dental Implant Placement Using a Task-Autonomous Robotic System Among Young Dentists From Different Specialties-A Pilot Module Study.

The learning curve effect of dynamic computer-assisted implant surgery (D-CAIS) was observed among inexperienced novice surgeons. The learning curves can provide valuable information for novice surgeons and valid comparisons between new and conventional techniques. Recently, robotic computer-assisted implant surgery (R-CAIS) has shown promise as a novel dental implant surgical technique for both partially and edentulous patients. However, its learning curve remains unknown. The aim of this study was to explore the learning curve of dental implant placement surgery with a task-autonomous robotic system among young dentists with different specialties. Four young dentists (mean age: 25.3 ± 1.5 years at the beginning of their first attempt) with equal representation of males and females and with different specialties participated in this study. None of the participants had prior experience in R-CAIS. Each operator placed eight implants over eight attempts using a semi-active task-autonomous robotic system. Among the eight implants, four were straight lateral incisor implants, and four were 30°-tilted premolar implants. The implants were placed in each dental quadrant of the maxillary and mandibular jaw modules. The operation time was recorded. Coronal, apical, and angular deviations between the planned and actual sites of implant placement were measured by merging preoperative and postoperative cone-beam computed tomography (CBCT) scans. The data were analyzed with repeated-measures ANOVA (α = 0.05). The mean time for implant placement was associated with the number of attempts (p < 0.01). The time taken for the second attempt was significantly shorter than that of the first attempt (33.26 vs. 30.47 min; p < 0.001) then it plateaued. Three-dimensional (3D) angular (p = 0.31), coronal deviation (p = 0.26), and apical deviation (p = 0.06) did not differ significantly among attempts. The mean values and standard deviations of 3D coronal deviation, 3D apical deviation, and 3D angular deviation were 0.71 ± 0.31 mm, 0.72 ± 0.30 mm, and 0.94 ± 0.58°, respectively. Neither the position of the jaw (p > 0.59) nor the tilt angle of the implant (straight or 30°-tilted, p > 0.85) was related to implant placement accuracy. Dentists quickly learned the basic workflow of R-CAIS and thus facilitated the clinicians in the mastery of implant placement on edentulous jaw modules, leading to a comparable operating speed and high precision. Moreover, the accuracy of placement of straight and tilted implants in both the maxilla and mandible with R-CAIS was satisfactory.

A New Pilot Hole Preparation System for Percutaneous Pedicle Screw Placement - A Randomized Controlled Study.

Randomized controlled study. To introduce a new pilot hole preparation system for percutaneous pedicle screw placement and investigate its efficiency and safety in comparison with the conventional method. Placing screws accurately, rapidly, and safely with less radiation exposure is critical for minimally invasive Lumbar interbody fusion (LIF). Optimizing pilot hole preparation instruments has important clinical implications. A total of 60 patients (180 screws) were included in this study. All patients were randomized into two groups (new system vs conventional method) and performed single-level minimally invasive percutaneous fixation, interbody fusion, and unilateral decompression. Basic information, time of pilot hole preparation, time of screw placement, and fluoroscopy time were recorded. Screw placement accuracy was graded based on the Gertzbein-Robbins scale, and the angle between the screw axis and the pedicle axis was collected in postoperative CT. There was no statistical difference in basic information between the two groups. The mean time of single pilot hole preparation was 4.08±1.01 min in the new system group and 5.34±1.30 min in the conventional method group (P<0.001). The time of single screw placement was significantly shorter in the new system group (0.82±0.20 vs 1.72±0.33min), and the fluoroscopy time was also less in the new system group (13.70±3.42 vs 19.95±5.50 s) (P<0.001). Screw placement accuracy assessment showed that there were 85 (94.45%) A-grade screws in the new system group while 76 (84.44%) A-grade screws in the conventional method group (P=0.027). The new pilot hole preparation system has shown significant reductions in the time of pilot hole preparation, time of screw placement, and radiation exposure, and has good clinical application value.

Real-time ultrasound to assess the umbilical catheter position in neonates: a randomized, controlled trial.

To compare real-time ultrasound (RT-US) use as an adjunct tool to verify umbilical catheter placement versus standard care without ultrasound. Neonates requiring umbilical venous catheter (UVC) and umbilical artery catheter (UAC) placement were randomized into the standard formula (No-US) and the RT-US groups. X-rays were used to confirm the catheter position. Fifty and forty-nine neonates were in the RT-US and No-US groups, respectively. RT- US showed a significantly higher rate of initial X-ray-confirmed proper catheter position than No-US (p < 0.001). The rates of proper positions of UVCs and UACs were significantly higher in the RT-US group than in the No-US group (both p < 0.001). Neonates in the RT-US group required fewer catheter adjustments and subsequent X-rays than those in the No-US group. RT-US enhances the accuracy of UVC and UAC placement, reduces catheter adjustments, and the number of X-rays required. TCTR20190622001.

Analysis of the accuracy between orthopedic robot-assisted and traditional manual pedicle screw placement techniques in adult degenerative scoliosis posterior surgery

Objective: To comparing the accuracy of pedicle screw placement in posterior surgery for adult degenerative scoliosis (ADS) between robotic-assisted and traditional freehand techniques. Methods: This retrospective study included 92 patients with ADS who underwent posterior spinal surgery at the First Affiliated Hospital of Nanjing Medical University (Jiangsu Province Hospital) between March 2019 and December 2023. There were 19 males and 73 females with a mean age of (63.6±9.8) years. The patients were divided into two groups based on the technique used for pedicle screw placement: robot-assisted group (34 cases) and manual group (58 cases). Operative duration, intraoperative blood loss, facet joint violation, postoperative complications, magnitude of curve correction, visual analogue scale (VAS) and Oswestry Disability Index (ODI) scores preoperatively, 1 week postoperatively, and 1 month postoperatively were compared and analyzed between the two groups. The Gertzbein-Robbins classification criteria was used to assess the accuracy of screw placement. Results: Differences in baseline data, operative duration, intraoperative blood loss, magnitude of curve correction, and VAS and ODI scores preoperatively, 1 week postoperatively, and 1 month postoperatively between the two groups exhibited no statistically significant differences (all P>0.05). The accuracy of pedicle screw placement in the robot-assisted group was significantly higher than that in the manual group [90.9% (416/458) vs 80.1% (697/870), P<0.001]. In terms of surgical segments, in T1-T12 and L1-S1 segments, the accuracy of pedicle screw placement in the robot group were both significantly higher than those in the control group [91.5% (130/142) vs 77.8% (186/239), P=0.001; 90.3% (271/300) vs 80.8% (502/621), P<0.001]. However, no significant differences was observed in the accuracy of S2-alar-iliac (S2AI) screw placement between the two groups [90.0%(9/10) vs 93.8%(15/16), P=0.727]. Moreover, no significant differences was found in the deviation direction of the cortical screw penetration between both groups (P=0.133). Significant differences were observed in the accuracy of screw placement between the Nash Moe 2 and 3 vertebral bodies in the robot group compared with those in the control group [88.9% (88/99) vs 71.0% (115/162), P=0.001; 89.2% (83/93) vs 60.2% (68/113), P<0.001]. Additionally, the incidence and grade of facet joint violation in the manual group were both significantly higher than those in the robot-assisted group (both P<0.001). No statistically significant differences was identified in postoperative complications between the two groups (P=0.841). Conclusion: It suggests that robot-assisted pedicle screw placement in posterior surgery for patients with ADS can significantly improve the accuracy of screw placement and reduce the incidence of facet joint violation.

Comparison of the accuracy and safety of robot-and navigation-assisted screw placement in atlantoaxial dislocation surgery

Objective: To compare the accuracy and safety of robot-assisted and navigation-assisted screw placement in atlantoaxial dislocation surgery. Methods: A retrospective analysis was conducted on the clinical data of 49 patients with atlantoaxial dislocation treated consecutively at the Honghui Hospital of Xi'an Jiaotong University from April 2022 to December 2023. Among them, 27 were male and 22 were female, aged (44.2±11.7) years. Based on the date of surgery, 29 patients (from April 2022 to April 2023) received the S8 navigation-assisted screw placement (navigation group), 20 patients (from May to December 2023) received Mazor robot-assisted screw placement (robot group). The accuracy of screw placement, screw placement time, operation time, intraoperative blood loss, and intraoperative complications were recorded and compared between the two groups. The Japanese Orthopedic Association (JOA) score and visual analog scale (VAS) score of pain were adopted to evaluate the recovery of cervical spinal cord function and cervical and shoulder pain at preoperative period and 3-month follow-up, and the occurrence of complications was observed. Results: A total of 196 screws were inserted in 49 patients. In the navigation-assisted group, a total of 116 screws were inserted with an accuracy rate of 93.1% (108/116); in contrast, in the robot-assisted group, a total of 80 screws were inserted with an accuracy rate of 97.5% (78/80) (P=0.040). The mean screw placement time, operation time, and blood loss in the navigation-assisted group were all significantly lower than those in the robot-assisted group [(37.8±3.4)min vs (48.4±4.6)min, (127.7±15.3)min vs (165.7±12.1)min and (205.8±13.6)ml vs (290.6±11.2) ml, respectively all P<0.01]. One case experienced intraoperative venous plexus injury in the robot-assisted group. Postoperatively, all patients experienced significant relief in neck pain symptoms, and neurological symptoms recovered to varying degrees. The VAS and JOA scores at 3 months post-surgery for both groups showed statistically significant improvements compared to pre-surgery (all P<0.01), but there was no statistically significant difference between the two groups (all P>0.05). Conclusions: Both robot-assisted and navigation-assisted screw placement show high accuracy and safety in atlantoaxial dislocation surgery. Compared to navigation, robot assistance increases the surgical time and blood loss, but significantly improves the accuracy of screw placement.

Efficacy comparison of robot-assisted versus freehand fluoroscopy-assisted minimally invasive transforaminal lumbar interbody fusion for degenerative lumbar spinal diseases

Objective: To compare the clinical and radiographic outcomes between robot-assisted minimally invasive transforaminal lumbar interbody fusion (RA MIS-TLIF) and fluoroscopy-assisted MIS-TLIF (FA MIS-TLIF) in patients with degenerative lumbar spinal diseases. Methods: The clinical data of 114 patients with lumbar degenerative diseases who underwent MIS-TLIF in Qilu Hospital of Shandong University from January 2019 to March 2022 were analyzed retrospectively. Fifty-eight patients underwent RA MIS-TLIF (robot group) and 56 patients received FA MIS-TLIF (freehand group). There were 16 males and 42 females in the robot group, with a mean age of (56.7±8.1) years. And there were 19 males and 37 females in the freehand group, with a mean age of (57.2±8.6) years. The clinical outcome parameters were the visual analog scale (VAS) of pain, Oswestry Disability Index (ODI) score, operative time, number of intraoperative fluoroscopies, blood loss, postoperative hospital stay and complications. The radiographic change measures were the accuracy of screw placement, facet joint violation (FJV), fusion status, and change in disc height at the proximal adjacent segment. All the patients were followed-up for 2-5 years. Results: There was no significant differences in the VAS and ODI scores, blood loss, or postoperative hospital stay between the two groups (all P>0.05). The operative time was longer in robot group than freehand group [(158.5±12.1) min vs (146.4±15.4) min, P<0.001]. There was no significant difference in the number of intraoperative fluoroscopies for patients between robot group and freehand group (P>0.05). The number of intraoperative fluoroscopies for the surgeon was significantly lower in robot group than freehand group (13.8±3.9 vs 74.7±6.8, P<0.001). The rate of a perfect screw position (grade A) was higher in robot group than freehand group [87.5%(203/232) vs 70.1%(157/224), P<0.001]. However, there was no significant difference in the proportion of clinically acceptable screws (grades A and B) between the two groups [98.3%(228/232) vs 96.9%(217/224), P=0.330]. The FJV grade was significantly higher in freehand group than robot group (0.43±0.68 vs 0.13±0.43, P<0.001). During at 2-year postoperative follow-up, there was no significant difference in the fusion status between the two groups (P>0.05); however, the decrease in disc height at the proximal adjacent segment was significantly less in robot group than freehand group [(0.63±0.38) mm vs (0.92±0.35) mm, P=0.001]. In the robotic group, a pedicle screw penetrated the outer wall of the vertebral pedicle in one patient, which was adjusted during surgery. In the freehand group, two screws were inserted too deeply and penetrated the anterior cortex, resulting in mild abdominal discomfort postoperatively, which resolved by the third day after surgery. Conclusions: Robot-assisted percutaneous pedicle screw placement is a safer and more accurate alternative to conventional freehand fluoroscopy-assisted pedicle screw insertion in MIS-TLIF. Compared with freehand MIS-TLIF, robot-assisted MIS-TLIF increases the operation time, but the accuracy of screw placement is higher, and the intraoperative radiation dose and the degree of adjacent segment degeneration are reduced.

Current status and future of application of spinal surgery robot in spinal deformity surgery

At present, spinal surgical robots can be used for preoperative surgical planning, pedicle screw placement, and intervertebral processing and intervertebral fusion in spinal deformity surgery. Existing spinal surgical robots have become the main means for spinal surgery to improve surgical accuracy and safety and reduce surgical complications. However, the efficiency of robot-assisted spinal deformity surgery is lower than that of traditional surgery, and there are shortcomings such as low accuracy of robot screw placement and fewer integrated functions. This article reviews the current application status and future development trends of spinal surgical robots in spinal deformity surgery.

Accuracy of robotic arm-assisted versus computed tomography-based navigation in total hip arthroplasty using the direct anterior approach: a retrospective study

BackgroundA robotic arm-assisted and a computed tomography (CT)- based navigation system have been reported to improve the accuracy of component positioning in total hip arthroplasty (THA). However, no study has compared robotic arm-assisted THA (rTHA) to CT-based navigated THA (nTHA) concerning accuracy of cup placement and acetabular fractures using the direct anterior approach (DAA). This study aimed to compare the accuracy of cup placement and the presence of intraoperative acetabular fractures between rTHA and nTHA using DAA in the supine position.MethodsWe retrospectively investigated 209 hips of 188 patients who underwent rTHA or nTHA using DAA (rTHA using the Mako system: 85 hips of 79 patients; nTHA: 124 hips of 109 patients). After propensity score matching for age and sex, each group consisted of 73 hips. We evaluated clinical and radiographic outcomes, comparing postoperative cup orientation and position, measured using a three-dimensional templating software, to preoperative CT planning. Additionally, we investigated the prevalence of occult acetabular fracture.ResultsClinical outcomes were not significantly different between the groups at 1 year postoperatively. The mean absolute error of cup orientation was significantly smaller in the rTHA group than in nTHA (inclination: 1.4° ± 1.2° vs. 2.7° ± 2.2°, respectively; p = 0.0001, anteversion: 1.5° ± 1.3° vs. 2.2° ± 1.7°, respectively; p = 0.007). The cases within an absolute error of 5 degrees in both RI and RA were significantly higher in the rTHA (97.3%) than in nTHA group (82.2%) (p = 0.003). The absolute error of the cup position was not significantly different between the two groups. The prevalence of occult acetabular fracture did not differ significantly between the two groups (rTHA: n = 0 [0%] vs. nTHA: n = 1 [1.4%]).ConclusionCup placement using DAA in the supine position in rTHA was more accurate with fewer outliers compared to nTHA. Therefore, rTHA performed via DAA in a supine position would be useful for accurate cup placement.

Routine ultrasound does not improve instrument placement at operative vaginal delivery: An updated systematic review and meta-analysis.

SynopsisRoutine ultrasound before operative vaginal delivery does not improve the accuracy of instrument placement.

Lumbar spine marker placement errors and soft tissue artifact during dynamic flexion/extension and lateral bending in individuals with chronic low back pain

Quantitative in vivo biomechanical assessments are typically performed with optoelectronic motion capture (MoCap) using retroreflective markers attached to skin. This technique inherently contains measurement errors from both marker placement on palpated bony landmarks and skin motion relative to the underlying bone (i.e., soft tissue artifact (STA)). Research on lumbar spine STA is scarce and limited to young, healthy participants in static positions. This study aimed to evaluate static placement errors, lumbar spine STA from MoCap marker clusters (MMC), and linear relationships between STA and patient characteristics. Thirty-nine participants with cLBP performed three trials each of flexion/extension and lateral bending while imaged simultaneously by MoCap (120 Hz) and dynamic biplane radiography DBR (20 Hz). MMCs were placed 29.5 ± 18.0 mm and 27.1 ± 13.4 mm superior to the most prominent aspect of the L1 and L5 spinous process, respectively. L1 relative to L5 STA was larger during flexion/extension (8.6 ± 5.7°) than lateral bending (4.5 ± 2.1°) (p < 0.001). After correcting for marker placement errors, components of the L1 and L5 STA averaged as much as 16.3 mm and 11.4° during flexion/extension, but only 4.0 mm and 4.8° or less during lateral bending. On average, STA for individual L1 and L5 vertebrae increased as participants moved away from the upright neutral position. STA was participant-dependent, however, age and BMI did not model STA well. Given the inaccuracy in marker placement and wide range of patterns of STA, caution is urged when making clinical decisions or when using computational models to estimate spine tissue loading based upon lumbar spine kinematics obtained from skin-mounted markers.

Drilling Optimization for Ultra-long Slim Hole Horizontal Wells in Duvernay Shale project, Canada

Abstract Objective/Scope(30-75): Drilling contractors have always strived to pursue higher single well production and lower well-construction cost in order to achieve higher return on investment. Efforts have been made in recent years to break technological barriers to create ultra-long(&gt;3500m) slim hole horizontal wells in Duvernay shale project. However, there were many challenges while extending the 6.75-in. slim hole laterals, such as 1) difficulty in weight transfer regarding motor slide drilling, 2) high down-hole friction torque and high ECD, 3) short servicing life and low efficiency of MWD, 4) inability to tracking thin substrata with limited logging tool, 5) production casing deployment challenges including stuck pipe risk and long running time. To overcome these obstacles, systematic solutions were proposed for unconventional ultra-long horizontal wells. Methods, Steps, and Process(75-100) : This paper proposes an integral drilling program to enhance overall drilling performance of ultra-long horizontal wells. First, Slim hole design to reduce well-construction cost through a reduction in steel, cement and fluid costs. Second, the upper drilling string upgraded from 4-in. drill pipes to 4.5-in. drill pipe with an advanced reduced OD premium connections, while Bottom Hole Assembly (BHA) employed even-wall stator PDM and Motorized RSS to improve drilling efficiency; Third, the OBM system is optimized for strong stability, lower friction, and clay-free invert emulsion to ensure safety drilling of longer laterals. Additionally, the MPD is equipped to maintain a lower ECD with minimal downhole losses; Then, a near-bit vibration sensor integrated into the RSS was deployed to provide real-time assessment of the severity of downhole shock and vibration. Reasonable drilling parameters were adjusted to reduce or eliminate downhole vibration and mitigate motor and MWD failure. Next, Azimuthal Gammy Ray was adopted and incorporated with dynamic drilling parameters data in real-time to optimize wellbore placement. More than 25 downhole drilling parameters were transmitted through high speed dual-telemetry MWD(xBolt) tool, boosting data transmission speeds and accuracy of wellbore placement in such a narrow stratigraphic window. Finally, a well-proven, external-grip mechanical casing running tool (CRT) was implemented specifically for smaller diameter 5.5-in. casing and a robust two-step wedge thread casing connection was designed to provide premium over torque capacity to manage longer lateral. Results, Understanding and Conclusions (100-200): Through continuous optimization and improvement, several major milestones and records were achieved such as longest 6.75-in. slim hole section (4875m) with one bit run and Bottom Hole Assembly, longest single run 5.5-in. &amp; 4.5-in. hybrid casing in Duvernay at 8157m utilizing CRT tool at the time, a recorded 19.2 days drilling performance from spud to TD was achieved without any accidents or incidents. More than 6 horizontal wells lateral length exceeds 4,000m, with an average horizontal ROP above 50m/h. Single well EUR increasing from 131,000 tons to 190,000 tons, much of this improvement was due to the use of longer Hz laterals drilling technologies. Innovation points, technological contributions, and Significance (30-75): The drilling technologies developed in Duvernay have significantly reduced costs per meter and improved efficiency, setting a new lateral record in the Western Canadian Sedimentary Basin. These advancements offer practical and effective references for horizontal wells in other regions, especially for unconventional gas/oil reservoir.

Improving Successful Cannulation of External Ventricular Drain: 3D-Printed Surgical Guide for Inexperienced Neurosurgeons

ObjectiveExternal Ventricular Drain (EVD) is a fundamental neurosurgical procedure that is commonly performed by junior neurosurgeons. Expedient, successful cannulation of the ventricles can be lifesaving. Yet, the free-hand technique of EVD insertion is associated with significant mal-positioning rates. This study aims to improve EVD placement by junior neurosurgeons with the aid of a customized 3D printed surgical guide. MethodsA 3D printed surgical guide was developed and customized to our institution’s EVD insertion procedure. First year neurosurgical residents were taught how to perform pre-operative trajectory planning based on coronal brain images and how to use the surgical guide during standard EVD insertion procedure. Number of passes, accuracy of EVD placement, operative complications, need for revision, and surgeon’s experience with the guide were recorded. Results14 patients underwent guide-assisted EVD insertion by first year neurosurgical residents. Significantly, 6 (43%) patients had ventricular anatomy distorted by midline shift. All surgeons achieved successful ventricular cannulation using the EVD guide on first pass (100%). 13 out of 14 (93%) of the guide-assisted EVDs were optimally placed (Karkarla Grade 1). 1 (7%) guide-assisted EVD was suboptimally placed (Karkarla Grade 2). There was no intra or post-operative complication and there was no EVD revision. ConclusionsFor inexperienced surgeons, the 3D printed EVD guide can improve ventricular cannulation even in cases of altered ventricular anatomy. The benefit of 3D printing would also allow the guide to be widely adopted by other institutions worldwide.

Ultrasound-guided core needle biopsy of deep fascia: A cadaveric study evaluating feasibility, accuracy and reliability.

Over the past few decades, researchers and clinicians have dedicated significant attention to fascial tissues. Current interest focuses on their anatomical and pathophysiological features. Breakthroughs in ultrasound (US) and magnetic resonance imaging (MRI) have enhanced our ability to study the dynamics and alterations of the tissue structures. However, a microscopic perspective is also essential for a comprehensive understanding of some pathologies of the fasciae. The aim of this study was to investigate, using a cadaveric study: (1) the ease of visualization of the landmarks used for the US-guided fascial core needle biopsy (CNB); (2) the consistency and accuracy of needle placement inside fascial layers using US guidance and confirmed by histological examination; (3) inter-rater reliability. We assessed the feasibility of US-guided CNB in different topographical regions of human cadavers: the thoracolumbar fascia (TLF), fascia lata (FL), and crural fascia (CF). The results, confirmed by histological examination, revealed no significant difference in needle placements between the in-plane approaches in the long and short axes for all locations and fasciae studied (long axis: 91.88%; short axis: 96.22%); p > 0.05. US-guided core needle biopsy with the in-plane approach is feasible, consistent and reliable. It could provide most or all of high-quality fascial tissue samples required for pathological examination. It could also reveal changes in fascial pathologies, capturing the exact site of pathology thanks to US guidance, in particular in patchy diseases such as eosinophilic fasciitis.

Accelerometer-based portable navigation system shows no superior accuracy over pelvic alignment guide for acetabular cup placement in total hip arthroplasty in lateral decubitus position.

Total hip arthroplasty (THA) using a portable navigation system (PNS) incurs costs per procedure. However, it does not require a large console. This study aimed to compare the accuracy of acetabular cup placement using a pelvic alignment guide (PAG) attached to the pelvis and an accelerometer-based PNS in THA performed in the lateral decubitus position. We retrospectively analyzed 100 hips that underwent primary THA in the lateral decubitus position between July 2018 and January 2021. The PAG was used in 50 hips, whereas the PNS was used in the other 50. Cup placement accuracy was measured using postoperative computed tomography scans, comparing errors in inclination and anteversion angles. The surgical time, blood loss, and complications were recorded. The follow-up period was at least 2 years in all cases. The mean absolute error of the inclination angle was similar between the groups (the PAG group: 3.7° ± 2.3° [range, 0.0-9.0]; the PNS group: 3.7° ± 2.3° [range, 0.2-10.5], p = 0.705). The mean absolute error of the anteversion angle was significantly smaller in the PAG group than in the PNS group (3.0° ± 2.4° [range, 0.0-9.7] vs. 6.5° ± 4.8° [range, 0.3-17.3], p < 0.001). The PAG group had a higher proportion of hips within 5° and 10° of the target angle (64 vs. 42%, P = 0.028, and 100 vs. 74%, p < 0.001, respectively). The PNS group had six hips with anteversion errors of 15° or more. Surgical time and blood loss were lower in the PAG group. The PNS group had one dislocation, whereas the PAG group did not. The accelerometer-based PNS did not demonstrate superior cup alignment accuracy compared to the PAG in THA performed in the lateral decubitus position. This finding informs surgeons that computer-assisted surgery is not necessarily superior to conventional THA using a PAG.

Computer-Assisted Total Hip Arthroplasty Improves Acetabular Prosthesis Placement Accuracy: A Multicenter, Randomized Controlled Clinical Study.

The long-term effectiveness of total hip arthroplasty (THA) largely depends on the accuracy of acetabular prosthesis placement. To improve the accuracy of acetabular prosthesis placement, we utilized a new surgical navigation system: visual treatment solution (VTS). The purpose of this study was to verify the efficacy and safety of this system in assisting THA. This was a prospective, multicenter, randomized controlled trial. One hundred and twenty-four patients undergoing primary THAs were included. The experimental group underwent VTS-assisted THA, and the control group underwent traditional surgical techniques. The main efficacy evaluation indicators were the proportion of anteversion and inclination angles in the Lewinnek safe zone, and secondary evaluation indicators included operation time, Western Ontario and McMaster University Osteoarthritis index (WOMAC) score, Harris score, short-form-36 (SF-36) score, and hip dislocation rate. Statistical analysis was performed mainly by t-test and chi-square test. The proportion of both anteversion and inclination angles in the safe zone was 93.1% in the experimental group and 50.9% in the control group; the difference was significant (p < 0.01). The average operation time was 112.5 min in the experimental group and 92.6 min in the control group; the difference was significant (p < 0.01). There were no significant differences in WOMAC score, Harris score, or SF-36 score between the experimental and control groups at 3 months after the operation (p > 0.05). The dislocation rate was 0% in the experimental group and 1.6% in the control group; the difference was not significant (p > 0.05). VTS-assisted THA can significantly improve the accuracy of acetabular prosthesis placement. However, there were no differences in short-term clinical outcomes or dislocation rates between the two groups.

Anatomical validation of needle placement for cervical paraspinal mapping of the multifidus.

The paraspinal muscles are an important component of electrodiagnostic testing for radiculopathy. In the cervical region, a protocol for cervical paraspinal mapping assumes accurate placement of the electromyography (EMG) needle into the cervical multifidus. However, there is scant information regarding the accuracy of needle placement in that muscle. This study examines the accuracy of this protocol in sampling the intended multifidus muscle of cadavers. An experienced electromyographer directed needles to multifidus at C5, C7, and T2 spinous processes of 19 embalmed cadavers, and injected color dyes. Separately another examiner dissected the cadavers, noting whether the dye was in the correct location and whether its trajectory approached any "danger zones" of nerve, artery, or joint. The dye was in the multifidus muscle 100% of the time and hit the intended bony target in 79%, 73%, and 79% of C5, C7, and T2 insertions. No insertion was found in a danger zone. The results indicate modest accuracy for EMG needle placement as proposed in the clinical protocol. Clinical utility of this method requires more work including the establishment of norms, sensitivities, specificities, and clinical impact.

A Multivariate Approach to Quantifying Risk Factors Impacting Stereotactic Robotic-Guided Stereoelectroencephalography.

Stereoelectroencephalography (SEEG) is an important method for invasive monitoring to establish surgical candidacy in approximately half of refractory epilepsy patients. Identifying factors affecting lead placement can mitigate potential surgical risks. This study applies multivariate analyses to identify perioperative factors affecting stereotactic electrode placement. We collected registration and accuracy data for consecutive patients undergoing SEEG implantation between May 2022 and November 2023. Stereotactic robotic guidance, using intraoperative imaging and a novel frame-based fiducial, was used for planning and SEEG implantation. Entry-point (EE), target-point (TE), and angular errors were measured, and statistical univariate and multivariate linear regression analyses were performed. Twenty-seven refractory epilepsy patients (aged 15-57 years) undergoing SEEG were reviewed. Sixteen patients had unilateral implantation (10 left-sided, 6 right-sided); 11 patients underwent bilateral implantation. The mean number of electrodes per patient was 18 (SD = 3) with an average registration mean error of 0.768 mm (SD = 0.108). Overall, 486 electrodes were reviewed. Univariate analysis showed significant correlations of lead error with skull thickness (EE: P = .003; TE: P = .012); entry angle (EE: P < .001; TE: P < .001; angular error: P = .030); lead length (TE: P = .020); and order of electrode implantation (EE: P = .003; TE: P = .001). Three multiple linear regression models were used. All models featured predictors of implantation region (157 temporal, 241 frontal, 79 parietal, 9 occipital); skull thickness (mean = 5.80 mm, SD = 2.97 mm); order (range: 1-23); and entry angle in degrees (mean = 75.47, SD = 11.66). EE and TE error models additionally incorporated lead length (mean = 44.08 mm, SD = 13.90 mm) as a predictor. Implantation region and entry angle were significant predictors of error (P ≤ .05). Our study identified 2 primary predictors of SEEG lead error, region of implantation and entry angle, with nonsignificant contributions from lead length or order of electrode placement. Future considerations for SEEG may consider varying regional approaches and angles for more optimal accuracy in lead placement.

Simplifying the Orientation of S1 Iliosacral Screws for Placement in the Dysmorphic Sacrum.

Determining the proper iliosacral screw orientation in a dysmorphic S1 sacral segment using a C-arm is difficult, and pelvic computed tomography (CT) is often necessary for the preoperative planning. On the preoperative pelvic axial CT section, the intended screw trajectory can be delineated intraosseously along the axis of the oblique osseous corridor. An inherently accurate orientation would be determined by 2 factors: (1) the trajectory is in the pelvic transverse plane, and (2) it is oriented relative to the coronal plane at a patient-specific angle, which should be measured preoperatively. Based on the above reasoning, we aimed to simplify and verify the orientation. After establishing the starting point on the sacral lateral view, we tested a method of simplifying the guidewire orientation: placing the guidewire in the pelvic transverse plane and then manipulating it to be angled relative to the coronal plane at the preoperatively measured patient-specific angle. The guidewire orientation should then be reproducibly accurate on the pelvic outlet and inlet views. The feasibility and safety of our method were verified through computer-simulated virtual surgical procedures in 95 dysmorphic sacra and clinical surgical procedures in 12 patients. The primary outcome parameters were the guidewire orientation and screw placement accuracy. Using our method, the S1 guidewire orientation was reproducibly accurate on the pelvic outlet and inlet views in all of the virtual and clinical surgical procedures. Ninety-five virtual S1 screws (1 screw in each left hemipelvis) were placed intraosseously in the pelvic transverse plane. Fourteen unilateral S1 screws were placed intraosseously in the pelvic transverse plane in the 12 patients (2 patients had double screws) without iatrogenic injuries. The guidewire orientation can be simplified by placing the guidewire in the pelvic transverse plane and replicating the preoperatively measured patient-specific angle between the guidewire and the coronal plane. After establishing the starting point on the sacral lateral view, our simplified manipulation yields a reproducibly accurate orientation on the pelvic outlet and inlet views. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Innovative 3D Navigation Module for Precise Unilateral Pedicle Screw Combined with Contralateral Translaminar Facet Screw Placement in Lumbar Spine Surgery.

The incidence of degenerative diseases of the lumbar spine has increased in recent years. Unilateral pedicle screw combined with contralateral translaminar facet screw fixation offers the advantages of less trauma, better stability, and fewer complications. However, the surgical difficulty and suboptimal pinning accuracy of translaminar facet screw placement in clinical practice limit its use. Therefore, in this study, we designed a novel suspended 3D-printed navigation module to facilitate fast and accurate intraoperative screw placement. The aim of this study is to investigate the digital design, precise implementation, and evaluation methods for placing unilateral pedicle screws in the lumbar spine combined with translaminar facet screw placement using a new suspended 3D navigation module. This retrospective study included 46 patients with single-level lumbar lesions who underwent spine surgery at the Affiliated Hospital of Putian University between June 2022 and December 2023. The suspended navigation module was designed digitally. Preoperative screw placement was simulated using 3D printed models, followed by an intraoperative accurate screw placement facilitated by the navigation module and a postoperative evaluation of the accuracy of screw placement. The absolute difference in three-dimensional coordinates of the inlet and outlet points of the preoperative design and the postoperative screw-nail channel served as the precision index. In a study involving 46 patients, surgery was successful with 92 pedicle screws and 46 translaminar facet screws placed without any penetration of the cortex. The difference in coordinates before and after screw insertion was minimal, with entry points varying between 1.21 to 1.36 mm and exit points between 1.97 to 2.46 mm. When screw accuracy met certain thresholds, there was no significant difference between preoperative design and postoperative coordinates, indicating precise replication of the surgical plan. The new suspended 3D navigation module enables the precise placement of unilateral pedicle screws in the lumbar spine combined with translaminar pedicle screws for precise surgery.