Search

Background: Computer-assisted navigation (CAN) and robotic assistance (RA) for total knee arthroplasty (TKA) are gaining in popularity. The purpose of this study is to update the literature on United States technology-assisted TKA trends of national utilization, regional utilization, and 90-day complication rates requiring readmission. Methods: Patients who underwent primary, elective TKA between 2010 and 2018 were retrospectively identified in the PearlDiver All Payer Claims Database (PearlDiver Technologies Inc.). TKAs were classified as conventional, CAN, or RA based on International Classification of Diseases nineth or tenth revision and Current Procedural Technology codes. Annual rates and regional trends of each type of TKA were reported. Ninety-day complications requiring readmission for each group were captured. Multivariable logistic regression was used to identify odds ratios (OR) for all-cause readmission based on TKA modality. Results: Of the 1,307,411 elective TKAs performed from 2010 to 2018, 92.8% were conventional, and 7.7% were technology-assisted (95.2% CAN and 4.9% RA). RA-TKA had the greatest increase in utilization (+2204%). The Western region had the highest utilization of technologies for TKA, while the Midwestern region had the lowest. Ninety-day postoperative complications requiring readmission were highest for conventional TKA and lowest for RA-TKA. RA-TKA (OR 0.68; 97.5% confidence interval 0.56-0.83, P < .001) and CAN-TKA (OR 0.93; 97.5% confidence interval 0.88-0.97, P < .05) had significantly lower odds of all-cause 90-day complications requiring readmission than conventional TKA. Conclusion: Utilization of RA-TKA and CAN-TKA continues to rise across the United States. The use of these technologies is associated with a lower OR of readmission within 90 days postoperatively.

BACKGROUND CONTEXT Computer-assisted navigation (CAN) has emerged in spine surgery as an approach to improve patient outcomes. While there is substantial evidence demonstrating improved pedicle screw accuracy in CAN as compared to conventional spinal fusion (CONV), there is limited data regarding clinical outcomes and utilization trends in the United States. PURPOSE The purpose of this study was to determine the utilization rates of CAN in the United States, identify patient and hospital trends associated with both techniques, and to compare their results. STUDY DESIGN Retrospective review of national database. PATIENT SAMPLE Nationwide Inpatient Sample (NIS), United States national database. OUTCOME MEASURES CAN utilization, mortality, medical complications, neurologic complications, discharge destination, length of hospital stay, cost of hospital stay. METHODS The NIS database was queried to identify patients undergoing spinal fusion with CAN or CONV. CAN and CONV utilization were tracked by year and anatomic location (cervical, thoracic, lumbar/lumbosacral). Patient demographics, hospital characteristics, index length of stay (LOS), and cost of stay (COS) were compared between the cohorts. After multivariate adjustment, index hospitalization clinical outcomes were compared. RESULTS A total of 4,275,413 patients underwent spinal fusion surgery during the study period (2004 to 2014). CONV was performed in 98.4% (4,208,068) of cases and CAN was performed in 1.6% (67,345) of cases. The utilization rate of CAN increased from 0.04% in 2004 to 3.3% in 2014. Overall, CAN was performed most commonly in the lumbar/lumbosacral region (70.4%) compared to the cervical (20.4%) or thoracic (9.2%) regions. When normalized to region-specific rates of fusion with any technique, the proportional utilization of CAN was highest in the thoracic spine (2.7%), followed by the lumbar/lumbosacral (2.2%) and cervical (0.9%) regions. CAN utilization was positively correlated with patient factors including increasing age and number of medical comorbidities. Multivariate adjusted clinical outcomes demonstrated that compared to CONV, CAN was associated with a statistically significant decreased risk of mortality (0.28% vs 0.31%, OR=0.67, 95% CI: 0.46-0.97, p=.035) and increased risk of blood transfusions (9.1% vs 6.7%, OR=1.19, 95% CI: 1.02-1.39, p=.032). However, there was no difference in risk of neurologic complications. CAN patients had an increased average LOS (4.44 days vs. 3.97 days, p CONCLUSIONS CAN utilization increased in the United States from 2004-2014. Use of CAN was proportionately higher in the thoracic and lumbar/lumbosacral regions and in older patients with more comorbidities. Given the continued trend towards increased CAN utilization, large-scale studies are needed to determine the impact of this technology on long-term clinical outcomes.

Study Design: Retrospective cohort study. Objective: To (1) define utilization trends for navigated instrumented posterior lumbar fusion (PLF), (2) compare reasons and rates of revision at 30-day, 60-day, 90-day, and 1-year follow-up, and (3) compare 90-day perioperative complications between navigated versus conventional instrumented PLF. Methods: Patients who underwent navigated or conventional instrumented PLF were identified from the Humana insurance database using the PearlDiver Patient Records between 2007-2017. Usage of navigation was characterized. Patient demographics and operative characteristics (number of levels fused, interbody usage) were compared between the 2 treatment groups. Propensity score matching was done and comparisons were made for revision rates at different follow-up periods (categorized by reasons) and other 90-day perioperative complications. Results: This study included 1,648 navigated and 23 429 conventional instrumented PLF. Navigated cases increased over the years studied to approximately 10% in 2017. Statistical analysis after propensity score matching revealed significantly lower rates of hardware-related revision at 90-day follow-up in the navigated cohort (0.49% versus 1.15%, P = .033). At 1-year follow-up, the navigated cohort continued to have significantly lower rates of hardware-related revision (1.70% versus 2.73%, P = .044) as well as all cause revision (2.67% versus 4.00%, P = .032). There were no statistical differences between the 2 cohorts in any of the 90-day perioperative complications studied, such as cellulitis and blood transfusion ( P > .05 for all). Conclusions: These findings suggest that navigation is associated with reductions in hardware-related revisions after instrumented PLF. However, these results should be interpreted cautiously in the setting of potential confounding by other unmeasured variables.

Background Computer-assisted navigation (CAN) has been shown to improve accuracy of screw placement in procedures involving the posterior cervical spine, but whether the addition of CAN affects complication rates, neurologic or otherwise, is presently unknown. The objective of this study is to determine the effect of spinal CAN on short-term clinical outcomes following posterior cervical fusion. Methods The American College of Surgeons National Surgical Quality Improvement Program database was queried from 2011 to 2018. Patients receiving posterior cervical fusion were identified and separated into CAN and non-CAN cohorts on the basis of a propensity score matching algorithm to select similar patients for comparison. Rates of 30-day unplanned readmission, reoperation, and other complications were evaluated. A separate matching algorithm was used to generate a subgroup of patients undergoing C1-C2 or occiput-C2 fusion for comparison of the same outcomes. Results A total of 12,578 patients met inclusion criteria, of which 689 received CAN and 11,889 did not. After adjusting for baseline differences, patients receiving CAN experienced longer operations and had higher total relative value units associated with care. There were no significant differences in 30-day complication, readmission, or revision rates. At the occipitocervical junction, there were more hardware revisions in the non-CAN group, but this effect did not reach statistical significance (2 vs. 0; P = 0.155). Conclusions Surgeons should embrace navigation in the cervical spine at their own discretion, as use of CAN does not appear to be associated with increased rates of surgical complications or readmissions despite longer operative time.

Study Design: Narrative Review. Objectives: The increasing cost of healthcare overall and for spine surgery, coupled with the growing burden of spine-related disease and rising demand have necessitated a shift in practice standards with a new emphasis on value-based care. Despite multiple attempts to reconcile the discrepancy between national recommendations for appropriate use and the patterns of use employed in clinical practice, resources continue to be overused—often in the absence of any demonstrable clinical benefit. The following discussion illustrates 10 areas for further research and quality improvement. Methods: We present a narrative review of the literature regarding 10 features in spine surgery which are characterized by substantial disproportionate costs and minimal—if any—clear benefit. Discussion items were generated from a service-wide poll; topics mentioned with great frequency or emphasis were considered. Items are not listed in hierarchical order, nor is the list comprehensive. Results: We describe the cost and clinical data for the following 10 items: Over-referral, Over-imaging & Overdiagnosis; Advanced Imaging for Low Back Pain; Advanced imaging for C-Spine Clearance; Advanced Imaging for Other Spinal Trauma; Neuromonitoring for Cervical Spine; Neuromonitoring for Lumbar Spine/Single-Level Surgery; Bracing & Spinal Orthotics; Biologics; Robotic Assistance; Unnecessary perioperative testing. Conclusions: In the pursuit of value in spine surgery we must define what quality is, and what costs we are willing to pay for each theoretical unit of quality. We illustrate 10 areas for future research and quality improvement initiatives, which are at present overpriced and underbeneficial.

Robotic guidance (RG) pedicle screw placement has been increasingly used to improve the rate of insertion accuracy. However, the superiority of the RG technique over computer-assisted navigation (CAN) remains debatable.To determine whether the Mazor RG technique is superior to CAN in terms of the rate of insertion accuracy and 4 other clinical indices, namely, intraoperative time, blood loss, complications and revision surgery caused by malposition.A search of PubMed, Embase, Cochrane, Web of Science, CNKI, and WanFang was conducted. We mainly aimed to evaluate the accuracy of pedicle screw placement between the Mazor RG and CAN techniques. The secondary objectives were intraoperative time, blood loss, complications, and revision surgery caused by malposition. The meta-analysis was conducted using the RevMan 5.3 and Stata 15.1 software.A randomized controlled trial and 5 comparative cohort studies consisting of 529 patients and 4081 pedicle screws were included in this meta-analysis. The RG technique has a significantly higher accuracy than CAN in terms of optimal (odds ratio [OR], 2.26; 95% confidence interval [CI], 1.85-2.76; P0.01) and clinically acceptable (OR, 1.69; 95% CI, 1.22-2.34; P = 0.002) pedicle screw insertions. Furthermore, the RG technique showed significantly less blood loss (mean difference, -42.49; 95% CI, -78.38 to -6.61; P = 0.02) than did the CAN technique but has equivalent intraoperative time (mean difference, 0.75; 95% CI, -5.89 to 7.40; P = 0.82), complications (OR, 0.65; 95% CI, 0.32-1.33, P = 0.24), and revision surgery caused by malposition (OR, 0.46; 95% CI, 0.15-1.43, P = 0.18).The Mazor RG technique is superior to CAN concerning the accuracy of pedicle screw placement. Thus, the Mazor RG technique is accurate and safe in clinical application.

OBJECTIVEResidency work-hour restrictions necessitate efficient, reproducible training. Simulation training for spinal instrumentation placement shows significant benefit to learners’ subjective and objective proficiency. Cadaveric laboratories are most effective but have high cost and low availability. The authors’ goal was to create a low-cost, efficient, reproducible spinal instrumentation placement simulation curriculum for neurosurgery and orthopedic surgery residents using synthetic models and 3D computer-assisted navigation, assessing subjective and objective proficiency with placement of thoracolumbar pedicle screws.METHODSFifteen neurosurgery and orthopedic surgery residents participated in a standardized curriculum with lecture followed by two separate sessions of thoracolumbar pedicle screw placement in a synthetic spine model utilizing 3D computer-assisted navigation. Data were collected on premodule experience, time and accuracy of screw placement, and both subjective and objective ratings of proficiency.RESULTSFifteen of 15 residents demonstrated improvement in subjective (Physician Performance Diagnostic Inventory Scale [PPDIS]) and 14 in objective (Objective Structured Assessment of Technical Skills [OSATS]) measures of proficiency in navigated screw placement with utilization of this curriculum (p < 0.001 for both), regardless of the number of cases of previous experience using thoracolumbar spinal instrumentation. Fourteen of 15 residents demonstrated decreased time per screw placement from session 1 to session 2 (p = 0.006). There was no significant difference in pedicle screw accuracy between session 1 and session 2.CONCLUSIONSA standardized curriculum using synthetic simulation training for navigated thoracolumbar pedicle screw placement results in significantly improved resident subjective and objective proficiency. Development of a nationwide competency curriculum using simulation training for spinal instrumentation placement should be considered for safe, efficient resident training.

Background. Computer-assisted navigation surgery has been gaining increasing importance in several orthopaedic fields in the last decade. However, none of the previous studies has described a navigated system in the intramedullary nailing of pertrochanteric femoral fractures. This prospective comparative study aims to compare, for the first time, a navigated pertrochanteric intramedullary nailing system (EBA NAV) to a traditional cephalo-medullary nail (EBA2). Materials and methods. 100 patients with 31-A1 or 31-A2 pertrochanteric femoral fractures were recruited from January to September 2020. Twenty patients were managed using the EBA-NAV system, whereas 80 patients were treated using a traditional cephalomedullary nail (EBA2) implanted under fluoroscopic guidance. The set-up time of the operating room (ST-OR), surgical time, exposure time to ionising radiation and the dose area product (DAP) were compared in the two groups. Results. Although the ST-OR was longer in patients managed with EBA NAV compared with EBA2 system, shorter surgical time and radiation exposure time was observed during EBA NAV surgery. Furthermore, significant DAP reduction was observed during the EBA NAV procedure. Conclusions. This preliminary study shows that EBA NAV navigated pertrochanteric intramedullary nail allows standardisation of the surgical technique, regardless of the surgeon’s experience, and significantly reduces exposure to ionising radiation, both in terms of time and DAP. EBA NAV could also play a key role in improving the learning curve of residents.

Melanocytic schwannoma is a rare nerve tumor characterized by melanin-producing neoplastic Schwann cells. Wide surgical resection is the management of choice for this tumor; however, anatomical location and proximity to nerve roots can make locating this tumor and the surgical resection challenging. Here we describe the case of 49-year-old male with a melanocytic schwannoma in the presacral area adjacent to the second sacral nerve root that was managed by wide resection aided by computer-assisted navigation due to the difficulty in identifying its location intraoperatively. The utilization of computer-assisted navigation improves accuracy and precision through the creation of a virtual continuous tridimensional map, particularly useful when oftentimes tumor margins may seem equivocal and further resection would compromise the patient's functionality. The value of computer-assisted navigation for soft tissue tumor resections in orthopedic oncology is still in its infancy, though, in certain scenarios it may advance the technique for some soft tissue resections.

PURPOSE: The main objective was to analyze the computer-assisted navigation (CAN)-specific complications that forced to switch to conventional procedure in primary total knee replacement (TKR). The secondary objective was to determine the influence of those complications on TKR short-term survival. METHODS: Retrospective study of 878 primary TKR in 753 patients. Two consecutive versions of the OrthoPilot navigation system (Braun Aesculap, Germany) were used during the study time. Specific complications of CAN were defined as those due to the instrumentation (hardware or software failures), which were classified in one of two categories according to whether they occurred during the registration or tracking process. RESULTS: There were 20 (2.3%) complications related to the navigation system use that forced to switch to conventional surgery: in 11 (1.2%) knees due to loosening of the tracking pins, and in the other nine (1.0%) there were information system failures. There was a trend for a higher conversion rate to conventional surgery with the use of the first version of the software. There were no fractures, infections, or nerve injuries at the pin site. We found no differences in the distribution of baseline variables among those with or without conversion to conventional surgery. There was no significant difference (p = 0.488) in the two year survival between patients with or without conversion. CONCLUSION: CAN for primary TKR is a safe method with few specific complications that forced to switch from the navigated to the conventional procedure. Conversion to conventional surgery did not affect the short-term survival of TKR.

Stereotactic navigation is quickly establishing itself as the gold standard for accurate placement of spinal instrumentation and providing real-time anatomic referencing. There have been substantial improvements in computer-aided navigation over the last decade producing improved accuracy with intraoperative scanning while shortening registration time. The newest iterations of modeling software create robust maps of the anatomy while tracking software localizes instruments in multiple display modes. As a result, stereotactic navigation has become an effective adjunct to spine surgery, particularly improving instrumentation accuracy in the setting of atypical anatomy. This article provides an overview of stereotactic navigation applied to complex cervical spine surgery, details the means for registration and direct referencing, and shares our preferred methods to implement this promising technology.

Summary Purpose The present study aimed to evaluate the symmetry of the orbital floor after maxillectomy and orbital floor reconstruction with individual titanium mesh using a computer-assisted navigation system. Patients and methods Nineteen patients who underwent orbital floor reconstruction with individual titanium mesh were included in this study. Postoperative computed tomography scans recorded after three-dimensional (3D) reconstruction were used to evaluate the symmetry of the orbital floor, including orbital floor height, orbital floor eminence, globe projection, orbital volume, and surface deviation. Results The average orbital floor height of the reconstructed and the unaffected side was 37.7 ± 2.3 and 37.8 ± 2.7 mm, respectively (P = .47). The average orbital floor eminence of the reconstructed and the unaffected side was 40.1 ± 5.5 and 39.6 ± 5.3 mm, respectively (P = .17). The average globe projection of the reconstructed and the unaffected side was 15.5 ± 3.2 and 15.3 ± 3.0 mm, respectively (P = .27). The average orbital volume of the reconstructed and the unaffected side was 25.9 ± 4.4 and 26.3 ± 4.4 cm3, respectively (P = .29). Repeatability between the reconstructed and the unaffected side was 88.3% ± 2.6% at within 1 mm and 98.6% ± 0.9% at within 2 mm. The average of maximum deviation was 2.4 ± 0.2 mm. Conclusion Individual titanium mesh is one of the best techniques for orbital floor reconstruction, as it can be placed precisely and helps achieve desirable esthetic outcomes through virtual surgical planning and using a computer-assisted navigation system.

To assess the impact of a computer assisted navigation system (CAN) (CT-Navigation™ IMACTIS, France) on patient radiation doses during percutaneous CT vertebroplasty a retrospective comparative trial was performed and included 37 patients requiring percutaneous vertebroplasty. This study was approved by CCN (Centre Cardiologique du Nord, Saint-Denis, France) ethical committee; all patients provided informed consent. All procedures were conducted in the interventional radiology department at CCN, by an experienced single radiologist using the same model and CT scan with identical parameters. The interventional dose length product (IDLP), representing the absorbed dose by the length of explored organs during the needle insertion phase, was compared in 15 consecutive patients who underwent a conventional procedure (CT control group), and in 22 patients who underwent CAN CT vertebroplasty (CAN group). The IDLP difference between the two groups was evaluated using Mann–Whitney U test. The median IDLP dose for the CAN group was 305.6 mGy.cm [182.3; 565.4], representing a reduction by a 3.2 factor compared with that of the conventional CT group (median 975.2 mGy.cm [568.3; 1077.1]; p vs. 100 min [82; 100] in the CT group (p ®) significantly reduced both patient radiation dose and procedure duration when compared to conventional CT guided percutaneous vertebroplasty.

Conversion of hip arthrodesis to total hip arthroplasty is associated with significant challenges, including accurate restoration of leg length and proper orientation of the acetabular component. Computer-assisted navigation provides real-time data on these parameters that may be a useful augment during hip fusion takedown surgery. Here, we present the case of a 64-year-old woman who presented with symptoms related to a left hip arthrodesis. The patient underwent a left-sided hip arthrodesis takedown and conversion to a total hip arthroplasty (THA). Due to the altered anatomical architecture of the fused hip, imageless navigation was used to assist with the conversion to THA. This case demonstrates that in complex hip arthroplasty procedures, where anatomical morphology is altered, navigation technology can be beneficial in addressing the challenges of achieving optimal placement of acetabular components and establishing appropriate leg length and offset.

Background Venous thromboembolism (VTE) is a major sequela after total knee arthroplasty (TKA). We prospectively compared the differences in the perioperative plasma d-dimer and fibrinogen levels between the individuals undergoing TKA via computer-assisted navigation and via a conventional method as the surrogate comparison for VTE. There were 174 patients fulfilling the inclusion criteria and providing valid informed consent between September 2011 and November 2013. There were 69 females and 20 males in the navigation-assisted group (median age: 71.00 years), while the conventional group was composed of 59 females and 26 males (median age: 69.00 years). Blood samples were obtained prior to and at 24 and 72 h after surgery for measurement of the levels of plasma d-dimer and fibrinogen. Results A significantly lower plasma d-dimer level 24 h after TKA (p = 0.001) and a milder postoperative surge 24 h after TKA (p = 0.002) were observed in patients undergoing navigation-assisted TKA. The proportions of subjects exceeding the plasma d-dimer cut-off values of 7.5, 8.6 and 10 mg/L 24 h after TKA were all significantly higher in the conventional group than in the navigation-assisted group (p = 0.024, 0.004, and 0.004, respectively). Conclusions A lower plasma d-dimer level and a milder surge in the plasma d-dimer level were observed in patients undergoing navigation-assisted TKA in comparison with patients undergoing conventional TKA 24 h after surgery. These findings may supplement the known advantages of navigation-assisted TKA.

Periacetabular osteotomy (PAO) is an effective surgical treatment for developmental hip dysplasia. The goal of PAO is to reorient the acetabulum to increase acetabular coverage of the femoral head, as well as to reduce contact pressures within the hip joint. The primary challenge of PAO is to accurately achieve the desired acetabular fragment orientation, while maximizing containment and congruency. As key parts of the procedure are performed out of direct field of view of the surgeon, combined with this challenge of precise spatial orientation, there is a potential role for technologies such as surgical navigation. Adjunctive technology may provide information on the orientation of repositioned acetabulum and may offer a useful assist in performing PAO. Here, we present a case of developmental dysplasia of the hip treated via PAO with the addition of an imageless computer navigation device. Surgery was successful, and, at 3 months after procedure, the patient was progressing well. To our best knowledge, this is the first case using imageless computer-assisted navigation in PAO surgery.

BACKGROUND Congenital maxillomandibular syngnathia is an extremely rare disorder characterized by craniofacial malformations and inability to open the mouth adequately, which leads to problems with feeding, swallowing, and breathing as well as temporomandibular joint ankylosis. The main goal of the surgery is to release the ankylosis, establish functioning mandible, and prevent re-fusion. However, surgical procedures for this disease are rarely reported. CASE SUMMARY Here, we report a 7-mo-old girl with bilateral maxillomandibular syngnathia. The patient presented with difficulty in feeding, breathing, sounding, and swallowing and had developmental dysplasia. For treatment, we performed bone isolation by computer-assisted navigation and used silicone to fix the wound surface to prevent refusion of bone. To our knowledge, this is the only syngnathia case in the literature treated using computer-assisted navigation. With the guidance of precise navigation, we were able to minimize operation time by at least one hour, the patient's blood vessels, nerves, and tooth germs were well protected, and excessive bleeding was avoided. After six weeks, the patient showed improvement in mouth opening and no major issues of feeding. CONCLUSION Application of computer-assisted navigation can significantly improve accuracy, effectiveness, and surgical safety in correcting congenital maxillomandibular syngnathia.

Study Design: Clinical case series describing a novel surgical technique. Objective: Stabilization across the cervicothoracic junction (CTJ) poses technical difficulties which make this procedure challenging. The transition from cervical lordosis to thoracic kyphosis and the orientation of the lateral masses of the cervical spine compared with the pedicles of the thoracic spine create the need to accommodate for 2 planes of alignment when placing instrumentation. A novel surgical technique for instrumentation across the cervicothoracic junction is described. Methods: The use of cortical bone trajectory (CBT) technique for pedicle fixation in the upper thoracic spine is described in combination with cervical lateral mass or pedicle screws. The application in our first 12 patients for stabilization across the CTJ is described. Two case presentations illustrate the technique. Results: All the patients had rod screw constructs without the need to skip levels, there was no requirement for transverse connectors and only 1 plane of contouring was required. Conclusions: The use of CBT technique has not been described for the upper thoracic spine. This technique avoids many technical problems associated with posterior instrumentation of the CTJ. The facility of their use in this application arises from the similar coronal plane entry points as the cervical lateral mass screws compared with the more lateral starting point of traditional thoracic pedicle screws. The technique has clinical equipoise to traditional thoracic pedicle screw insertion but with the benefits of an easier ability to perform the instrumentation and saving levels of fusion.

The purpose of this systematic review is to investigate the most common indications, treatment, and outcomes of computer-assisted surgery (CAS) in ophthalmological practice. CAS has evolved over the years from a neurosurgical tool to maxillofacial as well as an instrument to orbitofacial surgeries. A detailed and organized scrutiny in relevant electronic databases, journals, and bibliographies of the cited articles was carried out. Clinical studies with a minimum of two study cases were included. Navigation surgery, posttraumatic orbital reconstruction, computer-assisted orbital surgery, image-guided orbital decompression, and optic canal decompression (OCD) were the areas of interest. The search generated 42 articles describing the use of navigation in facial surgery: 22 on orbital reconstructions, 5 related to lacrimal sac surgery, 4 on orbital decompression, 2 articles each on intraorbital foreign body and intraorbital tumors, 2 on faciomaxillary surgeries, 3 on cranial surgery, and 2 articles on navigation-guided OCD in traumatic optic neuropathy. In general, CAS is reported to be a useful tool for surgical planning, execution, evaluation, and research. The largest numbers of studies and patients were related to trauma. Treatment of complex orbital fractures was greatly improved by the use of CAS compared with empirically treated control groups. CAS seems to add a favourable potential to the surgical armamentarium. Planning details of the surgical approach in a three-dimensional virtual environment and execution with real-time guidance can help in considerable enhancement of precision. Financial investments and steep learning curve are the main hindrances to its popularity.

BACKGROUND: Computer-assisted navigation system is well-known orthopaedic advancement which allow surgeon to obtain a real-time feedback during surgeries, thus helps to reduce intraoperative errors. Currently used navigation systems are tracker based, invasive and non-universal. Therefore this study was conducted to test novel tracker-less, image-based, non-invasive, universal, real-time navigation system to predict future position of the guide wire, K wire, screws and plates in orthopaedic trauma surgeries. METHODS: Firstly, the software was tested and validated on bone model. Then utilized for non-randomised comparative study conducted on 81 adult patients with stable intertrochanteric fracture treated by dynamic hip screw and barrel plate fixation. In one group, C-arm was used and in other, software navigation was used in addition to C-arm. Parameters such as time to insertion, number of C-arm shoots and number of attempts for guide wire insertion were documented and compared. RESULTS: Use of the navigation software for guide wire positioning in bone models and in the DHS barrel plate surgery proved to be significantly beneficial as compared to not using navigation. CONCLUSION: Intraoperative use of this new navigation system eliminates trial and error improving accuracy and reducing the operative time and radiation exposure. Thus this novel trackerless, C-arm image-based navigation system have potential to replace existing tracker-based navigation systems because of its universal nature, noninvasive and more effective properties.

Computer-assisted surgery (CAS) and navigation offers significant improvements in patient orientation and safety in every facet of our specialty of maxillofacial surgery. Ranging from precisely planned orthognathic procedures to the removal of foreign bodies requiring extremely flexible surgical options, and from minimally invasive dental implantology procedures to radical tumor resections of the skull base, they have made their mark for improving the procedure safety, predictability, and accuracy of surgery and options for intraoperative adaptations. In the future, the application of CAS is expected to further reduce operative risks and surgery time, accompanied by a considerable decrease in patient stress.Navigation systems are effective for delicate and accurate oral and maxillofacial surgery, neurosurgery, otolaryngology, and orthopedic surgery.This section presents an overview of available navigation systems and their applications with a focus on clinical utility and the solutions they offer for problems/challenges in the field of oral and maxillofacial surgery.

Nonunion of a type II odontoid fracture after the placement of an anterior odontoid screw can occur despite careful patient selection. Countervailing factors to successful fusion include the vascular watershed zone between the odontoid process and body of C2 as well as the relatively low surface area available for fusion. Patient-specific factors include osteoporosis, advanced age, and poor fracture fragment apposition. Cervical 1-2 posterior instrumented fusion is indicated for symptomatic nonunion. The technique leverages the larger posterolateral surface area for fusion and does not rely on bony growth in a watershed zone. Although loss of up to half of cervical rotation is expected after C1-2 arthrodesis, this may be better tolerated in the elderly, who may have lower physical demands than younger patients. In this video, we discuss the case of a 75-yr-old woman presenting with intractable mechanical cervicalgia 7 mo after sustaining a type II odontoid fracture and undergoing anterior odontoid screw placement at an outside institution. Cervical radiography and computed tomography exhibited haloing around the screw and nonunion across the fracture. We demonstrate C1-2 posterior instrumented fusion with Goel-Harms technique (C1 lateral mass and C2 pedicle screws), utilizing computer-assisted navigation, and modified Sonntag technique with rib strut autograft. Posterior C1-2-instrumented fusion with rib strut autograft is an essential technique in the spine surgeon's armamentarium for the management of C1-2 instability, which can be a sequela of type II dens fracture. Detailed video demonstration has not been published to date. Appropriate patient consent was obtained.

The accuracy of implantation using computer navigation and robotic total knee replacement (TKR) has been proven. Time taken during surgery has been a factor for surgeons for not using the technology. Aim of this study was to analyse time taken in different steps and identify which part needs improvement. Robotic time was compared to computer navigation. Methods: 15TKR were performed with MAKO robot. Software for the ligament balancing was used. All had CT scan preoperatively. Time of different surgical steps was recorded. Time for computer navigation was recorded too. After joint exposure, trackers and verification pins for tibia and femur were inserted. Femoral registration matching started at 10.8 minutes (SD3.3 Range7-20). It took 3.2 minutes to match femoral anatomy to CT scan. Tibial registration done at 14.1minutes (SD3 Range10- 23). Once matching was accepted to required accuracy, tibial cut was made at 22.2 minutes (SD4.4 Range 15-30). Next the soft tissues were assessed with tensioner. It took 6.3 minutes (SD 5.6). Final femoral preparation done at 35.7 minutes (SD 5.6 Range25-45). Trial performed at 52 minutes (SD7.3 Range42-63). Implants were cemented at 63.4 minutes (SD8 Range50-72). Wound closed at 77.6 minutes (SD9.5 Range65-97). The computer navigated TKR surgery took 70 minutes on an average. Compared to navigation, robotic technique took approximately 7 minutes longer, not significantly different. This could be due to learning curve of the surgical and theatre team. Improvement is required in different steps. The familiarity of staff will increase the efficiency. Registration matching took 11.4 minutes. Femoral preparation took 17 minutes. These steps could be streamlined.

Study Design: Cadaveric study. Objective: To evaluate accuracy, radiation exposure, and surgical time of a new robotic-assisted navigation (RAN) platform compared with freehand techniques in conventional open and percutaneous procedures. Methods: Ten board-certified surgeons inserted 16 pedicle screws at T10–L5 (n = 40 per technique) in 10 human cadaveric torsos. Pedicle screws were inserted with (1) conventional MIS technique (L2–L5, patient left pedicles), (2) MIS RAN (L2–L5, patient right pedicles), (3) conventional open technique (T10–L1, patient left pedicles), and (4) open RAN (T10–L1, patient right pedicles). Output included (1) operative time, (2) number of fluoroscopic images, and (3) screw accuracy. Results: In the MIS group, compared with the freehand technique, RAN allowed for use of larger screws (diameter: 6.6 ± 0.6 mm vs 6.3 ± 0.5 mm; length: 50.3 ± 4.1 mm vs 46.9 ± 3.5 mm), decreased the number of breaches >2 mm (0 vs 7), fewer fluoroscopic images (0 ± 0 vs 108.3 ± 30.9), and surgical procedure time per screw (3.6 ± 0.4 minutes vs 7.6 ± 2.0 minutes) (all P < .05). Similarly, in the open group, RAN allowed for use of longer screws (46.1 ± 4.1 mm vs 44.0 ± 3.8 mm), decreased the number of breaches >2 mm (0 vs 13), fewer fluoroscopic images (0 ± 0 vs 24.1 ± 25.8) (all P < .05), but increased total surgical procedure time (41.4 ± 8.8 minutes vs 24.7 ± 7.0 minutes, P = .000) while maintaining screw insertion time (3.31.4 minutes vs 3.1 ± 1.0 minutes, P = .650). Conclusion: RAN significantly improved accuracy and decreased radiation exposure in comparison to freehand techniques in both conventional open and percutaneous surgical procedures in cadavers. RAN significantly increased setup time compared with both conventional procedures.

Purpose:We have analyzed the surgical outcomes of primary total knee arthroplasty (TKA) using computer-assisted navigation that were performed by a single surgeon in terms of postoperative coronal alignment depending on preoperative varus deformity.Methods:We conducted a retrospective study of patients who have undergone navigated primary TKA from January 2016 through December 2019. Two hundred and fifty-six cases with varus deformity of 10° or less were assigned to group 1, and 216 cases with varus deformity of more than 10° were assigned to group 2. The postoperative mechanical hip–knee–ankle (mHKA) angle was measured from scanograms which were taken preoperatively and 3 months after surgery. The postoperative mHKA angle was targeted to be 0°, and the appropriate range of coronal alignment was set as 0 ± 3°.Results:The Pearson correlation showed a significant correlation with the degree of preoperative varus deformity and with the absolute error of postoperative mHKA ( p = 0.01). Among all patients, 64 cases (13.6%) were detected as outliers (mHKA > 0° ± 3°) at 3 months after surgery. Of the 64 cases, 25 cases (9.8%) were affiliated to group 1 and 39 cases (18.1%) were affiliated to group 2. Group 2 showed significantly higher occurrence of outliers than group 1 ( p = 0.01). Multiple variables logistic regression analysis, which analyzed the difference in the occurrence rate of outliers (mHKA > 0° ± 3°), showed that the occurrence rate of group 2 was 2.04 times higher than group 1. After adjusting for patient’s age, gender, and body mass index, the occurrence rate of outliers in group 2 was 2.01 times higher than group 1.Conclusion:The benefit of computer-assisted navigation during TKA in obtaining coronal alignment within 0 ± 3° may be lessened when the preoperative varus deformity is severely advanced.

The purpose of this study is to compare computer-assisted to manual implantation-techniques in total hip arthroplasty (THA) and to find out if the computer-assisted surgery is able to improve the clinical and functional results and reduce the dislocation rate in short-terms after THA. We performed a concise minimum 2‐year follow‐up of the patient cohort of a prospective randomized study published in 2014 and evaluated if the higher implantation accuracy in the navigated group can be seen as an important determinant of success in total hip arthroplasty. Although a significant difference was found in mean postoperative acetabular component anteversion and in the outliers regarding inclination and anteversion (p &lt, 0.05) between the computer-assisted and the manual-placed group, we could not find significant differences regarding clinical outcome or revision rates at 2-years follow-up. The implantation accuracy in the navigated group can be regarded as an important determinant of success in THA, although no significant differences in clinical outcome could be detected at short-term follow-up. Therefore, further long-term follow-up of our patient group is needed.

Rationale: In surgery of the lower jaw, the application of computer-assisted navigation is complicated and challenging due to the mobile nature of the mandible. In this study, we presented a computer-assisted navigation surgery for removal of the foreign body in the lower jaw with a mandible reference frame, basing on the strategy that the mandible is independent as an entity. Patient concerns: A 41-year-old male patient, identified as having a broken fissure bur that displaced into the mandibular lingual soft tissue, was referred to our department. The fissure bur broke accidentally and then displaced into the soft tissue when the patient underwent extraction of the left mandibular impacted third molar. Diagnosis: A metallic foreign body in the left lower jaw, confirmed by orthopantomography. Interventions: A computer-assisted navigation surgery with a customized mandible reference frame. Outcomes: The broken bur was removed successfully. Satisfactory wound healing and mouth opening was achieved, without postoperative complications. Lessons: Surgeons should be alert to the presence of broken bur in the lower jaw and avoid its displacement into deep facial space, and computer-assisted navigation with a mandible reference frame is recommended for removal of the foreign body in the lower jaw.

Inaccurate component placement during total hip arthroplasty (THA) can have significant and costly consequences. Malpositioning of the acetabular cup components can lead to dislocation and revision surgery, while postoperative discrepancies in leg length – the primary driver for litigation against orthopaedic surgeons – can lead to biomechanical imbalances, causing chronic low back pain. Current methods for monitoring these parameters intraoperatively rely on manual methods such as tissue tensioning or on the surgeon's experience, both of which are subject to inaccuracies. Computer-assisted navigation, while currently used in only a small percentage of THA procedures, is an emerging technology that has the potential to improve the accuracy with which surgeons place components during THA by providing real-time, intraoperative data. One innovative navigation system – Intellijoint HIP® (Intellijoint Surgical, Waterloo, ON) – has demonstrated its accuracy, time-neutrality, safety and effectiveness in several clinical studies and has the potential to improve outcomes and reduce re-admissions and revision during both primary and revision THA.

Summary: The oral and maxillofacial region has a complicated anatomy with critical contiguous organs, including the brain, eyes, vital teeth, and complex networks of nerves and blood vessels. Therefore, advances in basic scientific research within the field of intraoperative oral and maxillofacial surgery have enabled the introduction of the features of these techniques into routine clinical practice to ensure safe and reliable surgery. A navigation system provides a useful guide for safer and more accurate complex in oral and maxillofacial surgery. The effectiveness of a navigation system for oral and maxillofacial surgery has been indicated by clinical applications in maxillofacial trauma surgery including complex midfacial fractures and orbital trauma reconstruction, foreign body removal, complex dentoalveolar surgery, skull base surgery including surgery of the temporomandibular joint (TMJ), and orthognathic surgery. However, some fundamental issues remain involving the mobility of the mandible and difficulty in updating images intraoperatively. This report presents an overview and feasible applications of available navigation systems with a focus on the clinical feasibility of the application of navigation systems in the field of oral and maxillofacial surgery and solutions to current problems. Keywords: Navigation systems, Oral and maxillofacial surgery, Review

Introduction Lag screw cutout is one of the most commonly reported complications following intramedullary nail fixation of intertrochanteric femur fractures. However, its occurrence can be minimized by a well-positioned implant, with a short Tip-to-Apex Distance (TAD). Computer-assisted navigation systems provide surgeons with the ability to track screw placement in real-time. This could allow for improved lag screw placement and potentially reduce radiation exposure to the patient and surgeon. Methods Between Oct 2014 and Jan 2016, patients with intertrochanteric femur fractures being treated with intramedullary nail fixation by one of three fellowship-trained orthopaedic traumatologists were enrolled. Inclusion criteria were low-energy mechanism of injury and fracture class 31-A1/A2. Open fractures and patients with multiple injuries to the lower extremity were excluded. Patients were randomly assigned to computer-assisted navigation or a conventional fluoroscopic technique for lag screw placement. The primary outcomes were TAD, measured by postoperative anteroposterior and lateral x-rays by an independent reviewer, and radiation exposure measured in seconds of fluoroscopy time. Surgical time was also recorded. Results 50 patients were randomized, 26 to the computer-assisted navigation group and 24 to the control group. The mean manually-measured TAD in the computer-assisted navigation group was 14.1 mm ± 3.2 and in the control group was 14.9 mm ± 3.0 (p = 0.394). There was no difference between groups in total radiation time (navigation: 58.8 s ± 23.6, control: 56.5 s ± 28.5, p = 0.337) or radiation time during lag screw placement (navigation: 19.4 s ± 8.8, control: 18.8 s ± 8.0, p = 0.522). The surgical time was significantly longer in the computer-assisted navigation group with a mean surgical time of 45.8 min ± 9.8 compared to 38.4 min ± 9.3 in the control group (p = 0.009). Conclusions Computer-assisted navigation consistently produced excellent TADs, however it was not significantly better than conventional methods when done by fellowship-trained orthopaedic traumatologists. Surgeons with a lower volume trauma practice could potentially benefit from computer-assisted navigation to obtain better TAD.

Study Design Retrospective database study. Objective Navigation has been increasingly used to treat degenerative disease, with positive radiographic and clinical outcomes and fewer adverse events and reoperations, despite increased operative time. However, short-term analysis on treating adult spinal deformity (ASD) surgery with navigation is limited, particularly using large nationally represented cohorts. This is the first large-scale database study to compare 30-day readmission, reoperation, morbidity, and value-per-operative time for navigated and conventional ASD surgery. Methods Adults were identified in the National Surgical Quality Improvement Program (NSQIP) database. Multivariate regression was used to compare outcomes between navigated and conventional surgery and to control for predictors and baseline differences. Results 3190 ASD patients were included. Navigated and conventional patients were similar. Navigated cases had greater operative time (405 vs 320 min) and mean RVUs per case (81.3 vs 69.7), and had more supplementary pelvic fixations (26.1 vs 13.4%) and osteotomies (50.3 vs 27.7%) ( P Conclusions Despite controlling for patient-related and procedural factors, navigation independently predicted a 79% increased odds of reoperation but did not predict morbidity or transfusion. Readmission was similar between groups. This is explained, in part, by greater operative time and transfusion, which are risk factors for infection. Reoperation most frequently occurred for wound- and hardware-related reasons, suggesting navigation carries an increased risk of infectious-related events beyond increased operative time.

BACKGROUND CONTEXT Computer-assisted navigation (CAN) was developed to improve visualization inside the human body during surgery. This technology allows surgeons to more readily contextualize anatomical structures during complex procedures. The goal of CAN is to improve the accuracy and reproducibility of surgeries. PURPOSE Given the increased adoption of CAN for spine surgery, the objective of this study is to assess the charges, trends and usage of CAN in thoracolumbar spine surgery over time in order to better inform surgeons to changes in practice. METHODS The 2012-2016 National Readmission Databases (NRD) were queried for patients with ICD-9 and ICD-10 codes for computer-assisted procedures of the thoracolumbar region. Nonelective cases and patients RESULTS Following inclusion and exclusion criteria, 6,598 total patients were included, with 246 in 2012, 134 in 2013, 30 in 2014, 2,169 in 2015, and 4,019 in 2016 (Pearson correlation coefficient = 0.866, p = 0.057). Average total charge to a patient in 2016 was $142,013, which is greater than the 2012-2014 mean total charges of $126,698, $111,738, $115,120, and similar to the 2015 mean total charge of $148,134 (Pearson correlation coefficient = 0.660, p = 0.225). The ratio of patients covered under Medicare to those covered by private insurance increased from 0.822 in 2012 to 1.27 in 2016 (Pearson correlation coefficient 0.687, p = 0.313). CONCLUSIONS The use of and charges related to CAN in thoracolumbar surgeries has increased overall from 2012-2016, most notably indicated by the steep upward trend in use of this technology in 2016. This indicates an increasing adoption of a more recent innovation in assistive surgical technology, and an associated cost burden that comes with it. CAN has the potential to improve surgical outcomes, but as utilization grows and CAN becomes the standard in thoracolumbar spine surgeries, the charges for care also increase for more patients. As a result, further studies need to be conducted to determine whether the use of CAN is efficient in terms of cost and improvement of patient care. Limitations of this include the fact that there is no ICD-9 code for the use of CAN in thoracolumbar surgery specifically, so patient population was estimated using ICD-9 codes for CAN general use coupled with ICD-9 codes for thoracolumbar surgery. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.