Free-hand Screw Placement Research Articles

Comparative Efficacy and Safety of Robot-Assisted vs. Freehand Screw Placement in Femoral Neck Fractures: An Updated Systematic Review and Meta-Analysis.

Background: Femoral neck fractures pose significant surgical challenges with high morbidity and mortality. Traditional freehand screw placement often yields variable outcomes. Recent robotic advancements offer a promising alternative with enhanced precision. Methods: This systematic review compares the efficacy and safety of robot-assisted versus freehand techniques. A comprehensive literature search across multiple databases up to July 2024 included studies comparing both techniques. Primary outcomes were the union rate and time, functional outcomes, operative time, intraoperative parameters, and complication rates. Meta-regression analyses identified treatment response determinants. Results: Twenty-four studies (1437 patients) were included. Robot-assisted screw placement significantly improved the union rate, reduced the union time, and showed superior functional outcomes. Additionally, it resulted in shorter operative times, less intraoperative blood loss, and fewer instances of fluoroscopy and guide pin insertion. The risk of femoral neck necrosis was notably lower with robotic assistance. Meta-regression highlighted the robot type, patient age, and sample size as significant factors. Conclusions: Despite the promise of robot-assisted screw placement, limitations exist. The evidence being mainly from China raises concerns about generalizability. The lack of long-term follow-up data hinders assessment of technique durability. Unreported surgeon expertise levels and learning curves affect result validity. High initial costs and steep learning curves of robotic systems also present barriers to widespread adoption.

3D printing navigation template assisted pedicle screw placement for the treatment of typeⅡold odontoid fractures

To compare the safety and clinical efficacy of freehand and 3D printing navigation template assisted screw placement in patients with old odontoid fractures of typeⅡ. Total of 38 patients with old odontoid fractures of typeⅡwere treated from November 2018 to December 2022, all of which presented as chronic neck pain. According to the different methods of screw insertion into the pedicle, the patients were divided into a navigation template group and a freehand group. In the navigation template group, there were 17 patients including 9 males and 8 females with an average age of (51.30±13.20) years old, disease duration was (22.18±7.59) months. In the freehand group, there 21 patients including 7 males and 14 females with an average age of (49.46±11.92) years old, disease duration was (19.52±9.17) months. The intraoperative blood loss, operation time, and postoperative drainage output were recorded and compared between two groups. The accuracy of screw placement was evaluated by CT scan. Before operation and 1 year after operation, cervical pain was assessed by visual analogue scale(VAS), neurological changes were evaluated by the Japanese Orthopaedic Association (JOA) score, and the degree of spinal cord injury was assessed by the American Spinal Injury Association (ASIA) injury scale. All patients were followed up for (25.31±1.21) months. The operation time of template group (112.00±20.48) min had significantly shorter than that of the freehand group(124.29±15.24) min(P<0.05), while there were no significant differences between two groups in terms of intraoperative blood loss, postoperative drainage, and hospital stay(P>0.05). At 1 year after operation, in template group and freehand group, the VAS [(2.88±0.86), (2.90±0.83)] and JOA [(14.94±1.82), (14.62±2.19)] improved with preoperative [VAS(4.71±0.92), (4.86±0.79) and JOA (12.18±2.30), (11.95±2.31)](P<0.05), with no significant difference between two groups (P>0.05). No significant improvement was observed in ASIA grading in either group at 1 year after operation(P>0.05), and there was no significant difference between two groups(P>0.05). The template group had significantly better accuracy of screw placement in the pedicle of the axis than the freehand group (P<0.05), while no significant difference was observed between two groups in the accuracy of screw placement in the pedicle of the atlas (P>0.05). In the treatment of typeⅡold odontoid fractures with posterior pedicle screw fixation, 3D printing navigation template screw placement can significantly shorten the operation time, achieve similar clinical efficacy as free-hand screw placement, and significantly improve the accuracy of screw placement in the pedicle of the axis.

A clinical study of HoloSight Orthopaedic Trauma Surgery Robot-assisted infra-acetabular screw placement for acetabular fractures

To investigate the effectiveness of HoloSight Orthopaedic Trauma Surgery Robot-assisted infra-acetabular screw placement for treatment of acetabular fractures. The clinical data of 23 patients with acetabular fractures treated with open reduction and internal fixation and infra-acetabular screw placement in two medical centers between June 2022 and October 2023 were retrospectively analyzed. According to the the method of infra-acetabular screw placement, the patients were divided into navigation group (10 cases, using HoloSight Orthopaedic Trauma Surgery Robot-assisted screw placement) and freehand group (13 cases, using traditional X-ray fluoroscopy to guide screw placement). There was no significant difference in gender, age, body mass index, cause of injury, time from injury to operation, and Judet-Letournel classification between the two groups ( P>0.05). The time of infra-acetabular screw placement, the fluoroscopy frequency, the guide pin adjustment times, the quality of screw placement, the quality of fracture reduction, and the function of hip joint were compared between the two groups. All patients completed the operation successfully. The time of screw placement, the fluoroscopy frequency, and guide pin adjustment times in the navigation group were significantly less than those in the freehand group ( P<0.05). The quality of screw placement in the navigation group was significantly better than that in the freehand group ( P<0.05). Patients in both groups were followed up 6-11 months, with an average of 7.7 months. There were 9 and 9 cases in the navigation group and the freehand group who achieved excellent and good fracture reduction quality at 1 week after operation, and 12 and 12 cases with excellent and good hip joint function at last follow-up, respectively, and there was no significant difference between the two groups ( P>0.05). The fractures in both groups healed well, and there was no significant difference in healing time ( P>0.05). During the follow-up, there was no complication related to screw placement, such as failure of internal fixation, vascular and nerve injury, incisional hernia. In the treatment of acetabular fractures, compared with the traditional freehand screw placement, the HoloSight Orthopaedic Trauma Surgery Robot-assisted screw placement can reduce the time of screw placement, improve the accuracy of screw placement, and reduce the amount of radiation, which is an efficient, accurate, and safe surgical method.

Comparison of rehabilitation outcomes between robot-assisted and freehand screw placement in treatment of femoral neck fractures: a systematic review and meta-analysis

PurposeTo compare the postoperative rehabilitation of femoral neck fractures treated with robot-assisted nailing and freehand nailing.MethodsWe systematically searched the PubMed, EMBASE, Cochrane, China National Knowledge Infrastructure(CNKI), WanFang database, China Science and Technology Journal Database (VIP) and Web of Science databases to identify potentially eligible articles. Indispensable data such as the year of publication, country, study type, robot type, age, number of patients, sex distribution, study design, and outcome indicators were extracted. The outcome indicators of interest included healing rate, length of healing time, Harris score, operation time, frequency of X-ray fluoroscopy, frequency of guide pin insertion, and intraoperative blood loss. RevMan 5.4.1 was used for the meta-analysis.ResultsFourteen studies with 908 participants were included in this meta-analysis. The results showed that in terms of healing rate (SMD = 2.75, 95% CI, 1.03 to 7.32, P = 0.04) and Harris score (SMD = 2.27, 95% CI, 0.79 to 3.75, P = 0.003), robot-assisted screw placement technique scores were higher than the traditional freehand technique. Additionally, operative time (SMD = -12.72, 95% CI, -19.74 to -5.70, P = 0.0004), healing time (SMD = -13.63, 95% CI, -20.18 to -7.08, P < 0.0001), frequency of X-ray fluoroscopy (SMD = − 13.64, 95% CI, − 18.32 to − 8.95, P < 0.00001), frequency of guide pin insertion (SMD = − 7.95, 95% CI, − 10.13 to − 5.76, P < 0.00001), and intraoperative blood loss (SMD = − 17.33, 95% CI, − 23.66 to − 11.00, P < 0.00001) were lower for patients who underwent robotic-assisted screw placement than those for patients who underwent the conventional freehand technique.ConclusionCompared to the freehand nailing technique, robot-assisted nailing helps improve postoperative healing rates in patients with femoral neck fractures; shortens healing times; better restores hip function; reduces the number of intraoperative fluoroscopies, guides pin placements; reduces intraoperative bleeding; and increases perioperative safety.

Effects of Augmented Reality on Thoracolumbar Pedicle Screw Instrumentation Across Different Levels of Surgical Experience

Augmented reality (AR) is an emerging technology that may accelerate skill acquisition and improve accuracy of thoracolumbar pedicle screw placements. We aimed to quantify the relative assistance of AR compared with freehand (FH) pedicle screw accuracy across different surgical experience levels. A spine fellowship-trained and board-certified attending neurosurgeon, postgraduate year 4 neurosurgery resident, and second-year medical student placed 32 FH and 32 AR-assisted thoracolumbar pedicle screws in 3 cadavers. A cableless, voice-activated AR system was paired with a headset. Accuracy was assessed using χ2 analysis and the Gertzbein-Robbins scale. Angular error, distance error, and time per pedicle screw were collected and compared. The attending neurosurgeon had 91.6% (11/12) clinically acceptable (Gertzbein-Robbins scale A or B) insertion in both FH and AR groups; the resident neurosurgeon had 100% (9/9) FH and AR in both cases; the medical student had 72.3% (8/11) FH accuracy and 81.8% (9/11) AR accuracy. The medical student displayed significantly lower ideal (Gertzbein-Robbins scale A) FH accuracy compared with the resident neurosurgeon (P= 0.017) and attending neurosurgeon (P= 0.005), but no difference when using AR. FH screw placement was faster by both the attending neurosurgeon (median 46 seconds vs. 94.5 seconds, P= 0.0047) and the neurosurgery resident neurosurgeon (median 144 seconds vs. 140 seconds, P= 0.05). Total clinically acceptable AR and FH accuracy was 90.6% (29/32) and 87.5% (28/32), respectively (P= 0.69). AR screw placement allowed an inexperienced medical student to double their accuracy in 1 training session. With subsequent iterations, this promising technology could serve as an important tool for surgical training.

A Novel pedicle screw placement Surgery Based on Integration of Surgical guides and Augmented Reality.

Augmented reality is a new technology that, when applied to spinal surgery, offers the potential for efficient, safe, and accurate placement of pedicle screws. This study investigated whether augmented reality combined with a guide board improved the safety and accuracy of pedicle screw placement compared to traditional free-hand screw placement. Four trainers were divided into augmented reality navigation and free-hand groups. Each group consisted of a novice and an experienced spine surgeon. A total of 80 pedicle screws were implanted. First, the AR group reconstructed the 3D model and planned the screw insertion route according to the CT data of L2 lumbar vertebrae. Next, the Microsoft HoloLens™ 2 was used to identify the vertebral model, and the planned virtual path was superimposed on the real cone model. Next, the screw was placed according to the projected trajectory. Finally, Micron Tracker was used to measure the deviation of screws from the preoperatively planned trajectory, and pedicle screws were evaluated using the Gertzbein-Robbins scale. In the augmented reality group, the linear deviation of experienced doctors and novices was 1.59 ± 0.39 mm and 1.73 ± 0.52 mm, and the angle deviation was 2.72 ± 0.61° and 2.87 ± 0.63°, respectively. In the free-hand group, the linear deviation of experienced doctors and novices was 2.88 ± 0.58mm and 5.25 ± 0.62mm, and the angle deviation was 4.41 ± 1.18° and 7.15 ±1.45°, respectively. The screw accuracy rate was 97.5% in the augmented reality navigation group and 77.5% in the free-hand group. Augmented reality navigation improves the accuracy and safety of pedicle screw implantation compared with the traditional free-hand method and can assist inexperienced doctors in completing the surgery.

Learning Curves for Robot-Assisted Pedicle Screw Placement: Analysis of Operative Time for 234 Cases.

Robot-assisted pedicle screw placement is associated with greater accuracy, reduced radiation, less blood loss, shorter hospital stays, and fewer complications than freehand screw placement. However, it can be associated with longer operative times and an extended training period. We report the initial experience of a surgeon using a robot system at an academic medical center. We retrospectively reviewed all patients undergoing robot-assisted pedicle screw placement at a single tertiary care institution by 1 surgeon from 10/2017 to 05/2022. Linear regression, analysis of variance, and cumulative sum analysis were used to evaluate operative time learning curves. Operative time subanalyses for surgery indication, number of levels, and experience level were performed. In total, 234 cases were analyzed. A significant 0.19-minute decrease in operative time per case was observed (r = 0.14, P = .03). After 234 operations, this translates to a reduction in 44.5 minutes from the first to last case. A linear relationship was observed between case number and operative time in patients with spondylolisthesis (-0.63 minutes/case, r = 0.41, P < .001), 2-level involvement (-0.35 minutes/case, r = 0.19, P = .05), and 4-or-more-level involvement (-1.29 minutes/case, r = 0.24, P = .05). This resulted in reductions in operative time ranging from 39 minutes to 1.5 hours. Continued reductions in operative time were observed across the learning, experienced, and expert phases, which had mean operative times of 214, 197, and 146 minutes, respectively ( P < .001). General proficiency in robot-assisted surgery was observed after the 20th case. However, 67 cases were required to reach mastery, defined as the inflection point of the cumulative sum curve. This study documents the long-term learning curve of a fellowship-trained spine neurosurgeon. Operative time significantly decreased with more experience. Although gaining comfort with robotic systems may be challenging or require additional training, it can benefit surgeons and patients alike with continued reductions in operative time.

3D printed pedicle screw guides reduce the rate of intraoperative screw revision in adolescent idiopathic scoliosis surgery

Background ContextPedicle screw fixation has become common in the treatment of adolescent idiopathic scoliosis (AIS). Malpositioned pedicle screws have significant complications and identifying surgical techniques to optimize screw placement accuracy is imperative. PurposeTo compare the rate of intraoperative revision, replacement, or removal of pedicle screws placed utilizing 3D printed guides compared with pedicle screws placed utilizing a freehand technique. Study Design/SettingRetrospective cohort study/single academic center. Patient SampleThirty-two patients aged 10 to 18 with AIS. Outcome MeasuresRevision rate of pedicle screws and operative time between groups. MethodsA retrospective study was performed on patients 10 to 18 years of age who underwent posterior spinal instrumented fusion for AIS from February 2021 to July 2022. The study received an IRB exemption. Patient demographics, intraoperative measures, and outcome variables were recorded. Intraoperatively, all patients underwent a 3-dimensional fluoroscopic “check scan,” which included axial, sagittal, and coronal images, to assess for screw accuracy. A secondary outcome of operative time was compared between groups. The p-values <.05 were considered significant. ResultsA total of 32 patients were included in this study. There were 17 cases in the 3D guided and 15 cases in fluoroscopy-guided freehand cohort. There was a total of 254 pedicle screws using 3D guides and 402 screws using freehand technique. Between cohorts, there were no significant differences in a number of levels fused (p=.54) or length of surgery (p=.36). The total revision rate of 3D guided screw placement was 5.5% and that of the freehand technique was 8.5%. The freehand screw placement group had significantly higher revision rates per vertebral level compared with 3D guided (p=.0096). Notably, 3D printed guides had fewer screws that were removed/revised for being too anterior (7.1%) compared with freehand (23.5%). Surgical time was not significantly different between the 3D guided and freehand cohort (p=.35). Conclusions3D printed guides reduce intraoperative revision rate compared with freehand techniques. Total operative time is comparable to freehand technique.

Posterior instrumented correction and fusion of adolescent idiopathic scoliosis

Balanced frontal curve correction with horizontal shoulder levels, restoration of sagittal plane and vertebral derotation with afusion length as short as possible. Curves larger than 40-50° Cobb angle; furthermore age, location, degree of rotation, and sagittal plane deviation have to be considered. Posteriorly, segmental pedicle screw instrumentation with ahigh screw density (80%) and both titanium alloy and cobalt chrome rods. Freehand screw placement under consideration of both natural and deformity-induced pedicle morphology. Correction via reduction screws or instruments. Combined correction technique with rod rotation, segmental screw approximation to the generally concave rod and segmental correction of vertebral translation. Moderate concave distraction and convex compression. If needed, final in situ bending of the rods. Schwab typeI osteotomies; in rigid curves typeII osteotomies. Fusion with local bone, allogenic bone and/or bone substitutes (i.e.,tricalcium phosphate). Intraoperative placement of athoracic epidural catheter for postoperative pain control. Neurological monitoring throughout the procedure. Mobilization on postoperative day1 with focus on pain management and nutrition. Return to school after 4weeks. Physiotherapy after 3months, cycling after 3-6months, and full sport activities after 1year. Frontal curve correction of 60-80%, sufficient sagittal plane correction. Correction of rib hump 40%. Patient satisfaction is high at 95% and long-term revision rates of < 10%.

355 Robotic and Navigated Pedicle Screws Are Safer and More Accurate than Freehand Screws: A Systematic Review and Meta-Analysis

INTRODUCTION: Navigation and robotic pedicle screw placement systems have been developed to improve the accuracy of screw placement. However, the literature comparing the safety and accuracy of robotic and navigated screw placement with freehand screw placement in thoracolumbar spine surgery has been limited. METHODS: PubMed and EMBASE were systematically searched according to PRISMA guidelines. The search included indexed terms and text words from database inception to the date of the search (April 7th, 2022). Only randomized controlled trials comparing robotic assisted or navigated screws with fluoroscopic freehand screws in the thoracolumbar spine were included. Data and estimates were pooled using random-effects meta-analysis. Risk of bias was assessed using the Joanna Briggs Institute risk of bias tool. The main outcome measures were odds ratio estimates for screw accuracy according to the Gertzbein-Robbins scale and relative risk for various complications. RESULTS: A total of 14 papers encompassing 12 randomized controlled trials were identified. The pooled analysis demonstrated that robotic and navigated pedicle screw placement techniques were associated with increased odds of screw accuracy (OR 2.66, 95% CI 1.24-5.72, p = 0.0118). Robotic and navigated screw placement was associated with a lower risk of facet joint violations (RR 0.09, 95% CI 0.02-0.38, p = 0.0011) and major complications (RR 0.31, 95% CI 0.11-0.84, p = 0.0215). No differences were found in nerve root injury (RR 0.50, 95% CI 0.11-2.30, p = 0.3704), return to the operating room for screw revision (RR 0.28, 95% CI 0.07-1.13, p = 0.0744). CONCLUSIONS: These analyses suggest that robotic and navigated screw placement techniques are associated with higher odds of screw accuracy and superior safety profile compared to freehand techniques. Additional randomized controlled trials will be needed to further validate these findings.

Safety and Accuracy of Freehand Pedicle Screw Placement and the Role of Intraoperative O-Arm: A Single-Institution Experience.

Retrospective cohort study. The aim was to investigate the accuracy of pedicle screw placement by freehand technique and to compare revision surgery rates among three different imaging verification pathways. Studies comparing different imaging modalities in freehand screw placement surgery are limited. A single-institution retrospective chart review identified adult patients who underwent freehand pedicle screw placement in the thoracic, lumbar or sacral levels. Patients were stratified into three cohorts based on the intraoperative imaging modality used to assess the accuracy of screw position: intraoperative X-rays (cohort 1); intraoperative O-arm (cohort 2); or intraoperative computed tomography (CT)-scan (cohort 3). Postoperative CT scans were performed on all patients in cohorts 1 and 2. Postoperative CT scan was not required in cohort 3. Screw accuracy was assessed using the Gertzbein-Robbins grading system. A total of 9179 pedicle screws were placed in the thoracic or lumbosacral spine in 1311 patients. 210 (2.3%) screws were identified as Gertzbein-Robbins grades C-E on intraoperative/postoperative CT scan, 137 thoracic screws, and 73 lumbar screws ( P <0.001). Four hundred and nine patients underwent placement of 2754 screws followed by intraoperative X-ray (cohort 1); 793 patients underwent placement of 5587 screws followed by intraoperative O-arm (cohort 2); and 109 patients underwent placement of 838 screws followed by intraoperative CT scan (cohort 3). Postoperative CT scans identified 65 (2.4%) and 127 (2.3%) malpositioned screws in cohorts 1 and 2, respectively. Eleven screws (0.12%) were significantly malpositioned and required a second operation for screw revision. Nine patients (0.69%) required revision operations: eight of these patients were from cohort 1 and one patient was from cohort 2. When compared to intraoperative X-ray, intraoperative O-arm verification decreased the revision surgery rate for malpositioned screws from 0.37% to 0.02%. In addition, our analysis suggests that the use of intraoperative O-arm can obviate the need for postoperative CT scans.

Application of spinal surgical robots in minimally invasive surgery for thoracolumbar fracture

To evaluate the safety and accuracy of Renaissance robot navigation system in minimally invasive surgery for thoracolumbar fracture. The clinical data of patients with thoracolumbar fracture who underwent posterior minimally invasive pedicle screw internal fixation from July 2016 to July 2019 was retrospectively analyzed. And the patients were divided into robot group and artificial group. Robot navigation assisted screw placement was used in robot group, and traditional unarmed screw placement was used in artificial group. There were 20 patients in robot group, including 13 males and 7 females, aged from 23 to 69 years old with an average of(45.05±11.81)years old, one case was T11 fracture, 2 cases were T12, 10 cases were L1, 6 cases were L2 and 1 case was L3. There were 20 patients in artificial group, including 11 males and 9 females, aged from 26 to 65 years old with an average of(43.40±11.22)years old, 2 cases were T11 fractures, 7 cases were T12, 10 cases were L1, and 1 case was L3. The numbers of fluoroscopy, operation time and intraoperative blood loss were observed. The screw position was evaluated by Neo method. A total of 126 screws were implanted in robot group and 124 screws were implanted in artificial group. The operation time, fluoroscopy times, intraoperative blood loss were(115.75±14.26) min, (7.95±0.89) times and (132.50±29.36) ml in robot group and (129.50±10.50) min, (14.40±2.56) times and(182.50±23.14) ml in artificial group, respectively, there was significant difference between the groups(P<0.05). According to Neo classification method, there were 122 screws at grade 0, 4 screws at grade 1 in robot group, and there were 108 screws at grade 0, 9 screws at grade 1 and 7 screws at grade 2 in artificial group. The accuracy of the robot group was better than that of artificial group(P<0.05). Compared with free hand screw placement, Renaissance robot navigation system can effectively improve the accuracy of pedicle screw placement, reduce the number of fluoroscopy times and intraoperative blood loss, thereby improving the safety of operation.

Accuracy and safety of free-hand pedicle screw placement in cervical injury patients

Objectives: The purpose of this study was to describe the free hand method of pedicle screw placement without intraoperative imaging monitors and to evaluate the accuracy of the screw placement in quadriplegics patients. Methods: A free hand screw was inserted in the eleven cervical injury patients with quadriplegia. We studied the preoperative pedicle dimension in all the patients and assessed the clinical and radiological outcome and accuracy of the screw placement. Results: A total of 44 screws were inserted in the cervical pedicles of eleven patients. The postoperative images showed that 28 of the 44 screws had perforated the pedicles but none of them had breached the spinal canal. Among them 16 screws were grade 2 and 12 screws were grade 3. All the screws had penetrated the lateral wall. There were no neurovascular complications related to any malpositioned screw and there was no screw loosening or instrumentation failure in the patients. Conclusion: The free hand screw placement without intraoperative image guidance seems to be safe and effective method of fixation. But this technique requires sound knowledge of the cervical anatomy and experience and is useful in the places where navigation system are not available.

Clinical Outcomes of Robotic Versus Freehand Pedicle Screw Placement After One-to Three-Level Lumbar Fusion.

Retrospective cohort study. The purpose of this study is to compare patient-reported outcome measures (PROMs) for patients undergoing one-to three-level lumbar fusion using robotically assisted vs freehand pedicle screw placement. Patients who underwent either robotically assisted or freehand pedicle screw placement for one-to three-level lumbar fusion surgery from January 1, 2014 to August 31, 2020 at a single academic institution were identified. Propensity score matching was performed based on demographic variables. Clinical and surgical outcomes were compared between groups. Recovery Ratios (RR) and the proportion of patients achieving the minimally clinically important difference (%MCID) were calculated for Oswestry Disability Index, PCS-12, MCS-12, VAS Back, and VAS Leg at 1 year. Surgical outcomes included complication and revision rates. A total of 262 patients were included in the study (85 robotic and 177 freehand). No significant differences were found in ΔPROM scores, RR, or MCID between patients who underwent robotically assisted vs freehand screw placement. The rates of revision (1.70% freehand vs 1.18% robotic, P = 1.000) and complications (.57% freehand vs 1.18% robotic, P = .546) were not found to be statically different between the 2 groups. Controlling for demographic factors, procedure type (robotic vs freehand) did not emerge as a significant predictor of ΔPROM scores on multivariate linear regression analysis. Robotically assisted pedicle screw placement did not result in significantly improved clinical or surgical outcomes compared to conventional freehand screw placement for patients undergoing one-to three-level lumbar fusion.

3D printed templates improve the accuracy and safety of pedicle screw placement in the treatment of pediatric congenital scoliosis

BackgroundThree-dimensional (3-D) printed guidance templates are being increasingly used in spine surgery. The purpose of this study was to determine if 3D printed navigation templates can improve the accuracy of pedicle screw placement and decrease the complication rate compared to freehand screw placement in the treatment of children with congenital scoliosis.MethodsThe records of pediatric patients with congenital scoliosis treated at our hospital from January 2017 to January 2019 were retrospectively reviewed. Patients were divided into those where a 3D printed guidance templated was used and those in which the freehand method was used for pedicle screw placement. The accuracy rate of pedicle screw placement, surgical outcomes, and complications were compared between groups.ResultsA total of 67 children with congenital scoliosis were included (43 males and 24 females; mean age of 4.13 ± 2.66 years; range, 2–15 years). There were 34 children in the template-assisted group and 33 in the freehand group. The excellent accuracy rate of pedicle screw placement was significantly higher in the template-assisted group (96.10% vs. 88.64%, P = 0.007). The main Cobb angle and kyphosis angle were similar between the 2 groups preoperatively and postoperatively (all, P > 0.05), and in both groups both angles were significantly decreased after surgery as compared to the preoperative values (all, P < 0.001). The degree of change of the Cobb angle of the main curve and kyphosis angle were not significantly different between the 2 groups. There were no postoperative complications in the template group and 4 in the freehand group (0% vs. 12.12%; P = 0.009). All 4 patients with complications required revision surgery.

44. Does robotic vs freehand screw placement affect patient reported outcomes in 1-3 level lumbar fusion?

<h3>BACKGROUND CONTEXT</h3> Studies have shown robotically-assisted surgery demonstrates increased pedicle screw accuracy when compared to conventional freehand surgery. However, little research has been done to determine if this increased accuracy translates to improved clinical outcomes. <h3>PURPOSE</h3> The purpose of this study is to compare patient reported outcome measures (PROMs) for patients undergoing one to three level lumbar fusion using robotically-assisted vs freehand screw placement. <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort study. <h3>PATIENT SAMPLE</h3> Patients who underwent either robotically-assisted or freehand lumbar fusion surgery of one to three levels from January 1, 2014 to August 31, 2020. <h3>OUTCOME MEASURES</h3> Oswestry Disability Index (ODI), Form-12 Physical (PCS-12) and Mental (MCS-12) Composite scores, visual analogue scale (VAS) back and leg scores, incidence of revisions and surgical complications. <h3>METHODS</h3> Clinical and surgical outcomes were compared between groups. Recovery ratios (RR) and the number of patients achieving the minimally clinically important difference (MCID) were calculated for ODI, PCS-12, MCS-12, VAS Back and VAS Leg at 1-year postoperative. Surgical outcomes included complication and revision rates. Multivariate linear regression analysis was performed to determine the effect of surgery type (robotically assisted or freehand) on PROMs, controlling for age, gender, BMI and number of levels fused. <h3>RESULTS</h3> A total of 262 patients were included in the study, 85 robotically-assisted and 177 freehand. No significant differences were found in ∆PROM scores, RR, or MCID between patients who underwent robotically-assisted vs freehand screw placement. The rates of revisions (1.70% in freehand group vs 1.18% in robotic group, p = 1.000) and complications (1.10% in freehand vs 1.18% in robotic group, p=1.000) between the two groups were not statistically significant. Controlling for demographic factors, procedure type (robot vs freehand) did not emerge as a significant predictor of ∆PROM scores on multivariate linear regression analysis. <h3>CONCLUSIONS</h3> Robotically-assisted screw placement did not result in significantly improved clinical or surgical outcomes compared to conventional freehand screw placement. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

Surgical Drill Guide for Insertion of an Infra-Acetabular Screw Based on an Anatomically Precontoured Plate System: A Cadaveric Study.

Purpose Due to the anatomic structure of the pelvis, free-hand placement of screws in the acetabular fracture management can be difficult. Infra-acetabular screw fixation increases acetabular stability by distal fixation of the cup. Aim of this cadaveric study is to investigate if a plate-referenced drill guide can provide save placement of an infra-acetabular screw over a precontoured suprapectineal quadrilateral buttress plate (SQBP). Methods We constructed a drill guide for an infra-acetabular screw based on the surface of an anatomically precontoured SQBP. A total of 12 adult cadaveric acetabular specimens were used for drill guide-assisted placement of the infra-acetabular screw. The drill guide contains a radiopaque spiral to allow longitudinal fine adjustment of the SQBP along the pelvic brim to assure correct position of the plate-drill-guide construct in relation to the Koehler's teardrop. After screw placement, we conducted a computed tomography (CT) scan of all specimens to assess the actual position of the screw in relation of the infra-acetabular corridor and the acetabular joint surface. Results The position of the screw was within the infra-acetabular corridor in all cases. We did not see any intra-articular or intrapelvic screw penetration. The mean distance of the centerline of the screw to the medial border of the infra-acetabular corridor was 3.35 mm. The secure distance to the virtual surface of the femoral head to was 7.3 mm. Conclusions A plate-referenced drill guide can provide safe placement of an infra-acetabular screw for treatment of acetabular fractures. Radiographic fine adjustment is necessary to access the optimal entry point.

Evaluation of free-hand screw placement in cervical, thoracic, and lumbar spine by neurosurgical residents

BackgroundKnowledge of free-hand screw technique remains critical to adequately train neurosurgical residents. The purpose of this study was to evaluate the accuracy of screw placement via the free-hand technique in lumbar, thoracic, and cervical spine by neurosurgical residents completing an enfolded spine fellowship. MethodsMedical records of all patients who underwent free-hand screw placement at all spinal levels over a 6-month period by senior neurosurgical residents enrolled in an in-folded spine fellowship were retrospectively reviewed. Postoperative CT images were assessed for presence and direction of cortical breach. ResultsTwenty-six patients underwent 162 free-hand screw placements. The most commonly placed screws were cervical lateral mass screws (n = 69), thoracic (n = 41), and lumbar pedicle screws (n = 41). The most common indication for surgery was deformity (n = 22), followed by infection (n = 2) and trauma (n = 2). Fifty-five breaches were identified in 44 (27 %) screws placed in 21 patients (81 %). Anterior breach was identified in 22 cases (40.0 %), lateral in 12 (23.6 %), superior in 7 (12.7 %), and inferior in 7 (12.7 %), and medial in 6 (10.9 %). The most common level of breach was observed in cervical lateral mass screws (n = 19, 43 %) and least common in C2 pars screws (n = 1, 2%). With an average length of follow up of 12.1 ± 7.7 months of follow-up, no clinical sequalae of screw breach was observed. ConclusionsDespite the high prevalence of screw breach using the free-hand technique by neurosurgical residents, the absence of clinical sequelae implies safety and emphasizes the importance of early exposure to this technique during neurosurgical residency training.

Comparison of the 3D-printed operation guide template technique and the free-hand technique for S2-alar-iliac screw placement

BackgroundTo compare the safety and accuracy of the 3D-printed operation guide template technique and the free-hand technique in the placement of the S2-alar-iliac (S2AI) screw.MethodsWe conducted a retrospective analysis of 47 patients undergoing S2AI screw placement in our hospital, divided into the 3D-printed operation guide template group and the free-hand screw placement group. The duration of single S2AI screw placement was documented in all patients. A postoperative CT scan was performed to assess screw placement effectiveness according to the distance from the screw tip to the breach of the cortical bone wall.ResultsIn total, 42 screws were placed in the guide template group, with an average screw placement duration of 151.6 ± 44.8 s. Screw placement grading was as follows: 40 screws in grade 0, two in grade 1, and none in grades 2 and 3. This grading resulted in excellent and good rates of 95.2% and 100%, respectively. In total, 52 screws were placed in the free-hand group, with an average screw placement duration of 138.3 ± 45.9 s. Screw placement grading was as follows: 42 screws in grade 0, seven in grade 1, three in grade 2, and none in grade 3. This grading resulted in excellent, good and acceptable rates 80.8%, 94.2% and 100%, respectively. Screw placement duration did not significantly differ between the groups (p > 0.05). The excellent rate of screw placement was greater in the guide template group than in the free-hand group (p < 0.05), but the good and acceptable rates did not significantly differ between the two groups (p > 0.05).ConclusionBoth techniques can be applied to S2AI screw placement. The 3D-printed guide technique is superior to the free-hand technique in terms of safety and accuracy.

Clinical and Radiologic Outcomes of Thoracolumbar Fusions Using Intraoperative CT Guidance and Stereotactic Navigation in a Spinal Trauma Population: An Analysis of 58 Patients.

Retrospective review of prospectively collected single-institution database. To analyze the clinical and radiographic outcomes of posterior thoracolumbar fusions using intraoperative computed tomography (CT)-guidance and stereotactic navigation in thoracolumbar spinal trauma. Pedicle screw instrumentation is utilized for stabilization in thoracolumbar fusions. Suboptimal placement may lead to neurovascular complications, pseudarthrosis, postoperative pain, and the need for revision surgery. Image-guided spinal surgery is commonly used to improve accuracy, particularly for complex anatomy such as encountered with traumatic fractures. We retrospectively identified 58 patients undergoing posterior thoracolumbar fusions using intraoperative CT and stereotactic navigation for traumatic fractures from 2010 to 2017 at a single institution. Pedicle screw accuracy, realignment, clinical outcomes, and ease of use were retrospectively reviewed. Accuracy was assessed on postplacement or postoperative CT. Breach grades included: grade 1 (<2 mm), grade 2 (2-4 mm), and grade 3 (>4 mm). A total of 58 patients were identified having undergone 58 operations, which involved placement of 519 pedicle screws. Traumatic fracture patterns and levels of injury were varied. Accurate pedicle screw placement was found in 95.8% and was stable over time. Breach included: grade 1 in 19 screws, grade 2 in 2 screws, and grade 3 in 1 screw. No neurovascular complications were noted. No revision surgery was performed for misplacement. A subgroup of 6 ankylosing spondylitis patients were identified having undergone 6 operations with 63 pedicle screws. Accurate pedicle screw placement was found in 93.7%. Intraoperative CT-guidance and stereotactic navigation can overcome the difficulty associated with thoracolumbar trauma resulting in complex anatomy with malalignment and unpredictable trajectories. Intraoperative CT can be used with stereotactic guidance or for intraoperative verification of free-hand screw placement with repositioning as needed. CT-guidance maintains the benefit of reduced fluoroscopic exposure while improving accuracy of instrumentation and reducing reoperation for screw malposition.