Use Of Computer Navigation Systems Research Articles

Virtual simulation, preoperative planning and intraoperative navigation during laparoscopic partial nephrectomy.

IntroductionThe use of computer navigation systems is a new and actively explored method used for surgical procedures concerning the abdominal and retroperitoneal organs. In this paper, we propose an original hardware – software complex, which forms a virtual body model, based on preoperative computer tomography data, transmitted to the operating screen monitor using a surgical navigation system, involving a mechanical digitizer.Material and methodsDuring a laparoscopic procedure, a three-dimensional (3D) model of a kidney with a tumor was used to obtain additional information on the primary or secondary monitor or for combining the virtual model and video images on the main or additional monitor in the operating room. This method was used for laparoscopic partial nephrectomy, where twelve patients were operated with an average age of 45.4 (38–54) years, with clear cell renal cell carcinoma size 27.08 (15–40) mm.ResultsAll patients successfully underwent laparoscopic partial nephrectomy with intraoperative navigation. The mean operative time was 97.2 (80–155) minutes, warm ischemia time – 18.0 (12–25) minutes. Selective clamping of segmental renal arteries was performed in 7 (58.3%) cases, in the remaining 5 (41.6%) cases the renal artery was clamped. There were no serious complications. The average duration of hospital stay was 7.0 (5–10) days.ConclusionsPreliminary results of our clinical study have shown the success of 3D modeling for qualitative visualization of kidney tumors in the course of surgical intervention, both for the surgeon and for the patient to understand the nature of the pathological process.

Current concepts and future perspectives in computer-assisted navigated total knee replacement.

Total knee replacements (TKR) aim to restore stability of the tibiofemoral and patella-femoral joints and provide relief of pain and improved quality of life for the patient. In recent years, computer-assisted navigation systems have been developed with the aim of reducing human error in joint alignment and improving patient outcomes. We examined the current body of evidence surrounding the use of navigation systems and discussed their current and future role in TKR. The current body of evidence shows that the use of computer navigation systems for TKR significantly reduces outliers in the mechanical axis and coronal prosthetic position. Also, navigation systems offer an objective assessment of soft tissue balancing that had previously not been available. Although these benefits represent a technical superiority to conventional TKR techniques, there is limited evidence to show long-term clinical benefit with the use of navigation systems, with only a small number of studies showing improvement in outcome scores at short-term follow-up. Because of the increased costs and operative time associated with their use as well as the emergence of more affordable and patient-specific technologies, it is unlikely for navigation systems to become more widely used in the near future. Whilst this technology helps surgeons to achieve improved component positioning, it is important to consider the clinical and functional implications, as well as the added costs and potential learning curve associated with adopting new technology.

Tibial Stress Fracture After Computer-Navigated Total Knee Arthroplasty

In this case report, the patient experienced a stress fracture at one of the pinhole sites used for placement of the computer navigation system’s tibial trackers. Introduction The use of computer navigation systems in total knee arthroplasty (TKA) has become increasingly popular in recent years. Many authors have already documented satisfactory short- to mid-term results after using various types of software [1-3].Bathis et al [4], as well as Decking et al [5] and Rosenberger et al [6], showed how the use of navigation systems can improve the accuracy of the femoral and tibial component placement when compared with the “traditional” techniques. Because a correct alignment of the components is one of the most important factors determining favorable long-term results of a TKA, this could lead to a higher longevity of the prosthesis.Despite these positive aspects, some authors have reported no advantages, as well as a longer operative time with the use of computer-assisted systems [7,8]. Moreover, recently three cases of stress femoral or tibial fractures have been reported as a complication of navigated TKA [9,10].We present a case of a stress fracture of the tibial diaphysis that occurred after a TKA performed with the use of a computer navigation system. The stress fracture occurred at one of the pinhole sites used for the placement of the tibial trackers.We have been using computer navigation systems since 2005 as a standard procedure for TKA. This complication occurred after a series of 155 (0.64%) uncomplicated procedures (ie, well after the learning curve was complete).

Alignment outcomes in navigated total knee arthroplasty: a meta-analysis

Whether navigated total knee arthroplasty can improve the limb and component alignment is a matter of debate. This systematic literature review analyzed the differences on alignment outcomes between navigated total knee arthroplasty and conventional total knee arthroplasty. Multiple databases, online registers of randomized controlled trials were searched. Published and unpublished randomized controlled trials were included, and data on methodological quality, population, intervention, and outcomes were abstracted in duplicate. Data were pooled across studies, and odds ratios for categorical outcomes were calculated according to study sample size. Twenty-one randomized controlled trials of varying methodological quality involving 2,414 patients were included. Statistically significant differences were observed between navigated group and conventional group in mechanical axis malalignment of >3° (odds ratio, 0.26; 95% confidence interval, 0.17-0.38) and mechanical axis malalignment of >2° (odds ratio, 0.33; 95% confidence interval, 0.26-0.42). Navigated group had a lower risk of malalignment for both coronal femoral component and coronal tibial component of >3° and >2°. Both sagittal femoral component alignment and tibial slope showed statistical significance in favor of navigated arthroplasty at >2° and 3° malalignment. Meta-analysis indicates significant improvement in alignment of the limb and the component position with use of computer navigation system. Its clinical benefits are unclear and remain to be defined on a larger scale randomized controlled trials with long-term follow-up. Therapeutic study (Systematic review of Level-I studies with inconsistent results), Level II.

Computer-Navigated Surgery in Anterior Cruciate Ligament Reconstruction: Are Radiographic Outcomes Better Than Conventional Surgery?

The use of computer navigation systems in anterior cruciate ligament (ACL) has been the subject of debate. However, there is a lack of systematic review to analyze the radiographic outcomes after computer-navigated ACL reconstruction. We searched, in duplicate, Medline, Embase, and Web of Science databases for randomized controlled trials (RCTs)/quasi-RCTs comparing conventional versus computer-navigated ACL reconstruction. Two reviewers independently extracted the data. Radiographic outcomes reported in a majority of included trials were meta-analyzed using the Mantel-Haenszel test statistic. After applying our eligibility criteria, we had 5 trials for systematic review and data synthesis. There was no evidence of statistical heterogeneity between all included studies. Both navigated and conventional ACL reconstructions placed the tibial tunnel in acceptable positions. The risk of notch impingement was reduced in the navigated group in comparison with the conventional group. A computer navigation systems may reduce variation from optimal graft alignment and notch impingement. However, there is a need for further high-quality studies with long-term follow-up, so as to prove the clinical significance of these findings. Level II, systematic review of randomized controlled trials.

Experimental validation of a pinless femoral reference array for computer‐assisted hip arthroplasty

The use of computer navigation systems during total hip arthroplasty requires the femoral fixation of a reflective dynamic reference base (DRB), which theoretically involves the risk of bony fracture, infection, and pin loosening. The first objective of this study was to evaluate the relative movements between a novel, noninvasive external femoral DRB system and the femur. Secondly, the maximum effects of these 3D movements on intraoperative, computer-assisted leg length and offset measures were evaluated. An imageless navigation system was used to track the positions of the soft tissue attached, pinless DRB relative to an invasive reference marker on the femur during a less-invasive, anterior surgical hip approach. Relative translatory movements up to 8.2 mm mediolaterally and up to 8.8 degrees in rotation were measured. Using a measurement technique in which the calculation of leg length and offset changes is primarily based on a specific realignment of the leg, maximum differences of 1.3 mm for leg length and 1.2 mm for offset were found when comparing the pin-based and pinless methods. Thus, invasive fixation techniques with screws or pins are still the method of choice when standard measurement algorithms for intraoperative leg length and offset measures are used. Though direct translatory and rotational variations between the pinless array and the femoral bone were detected, the pinless array can be used to assess leg length and offset when used with a specific measurement technique that compensates for such variations.

Computer Navigation in Balloon Kyphoplasty Reduces the Intraoperative Radiation Exposure

Comparison of the dose area product (DAP), the radiation time and the operation time during computer navigated and conventional balloon kyphoplasty procedures. To compare the patients radiation exposure and operation time in a balloon kyphoplasty procedure with and without using a navigation system for the placement of working needles. Minimal invasive spine surgery is associated with high radiation exposure for both the patient and the surgeon. The use of computer navigation has led to a reduced radiation exposure in experimental trials. To our knowledge, there is no clinical data determining the influence of computer navigation on radiation exposure and operation time in a balloon kyphoplasty procedure. Twenty-nine patients with 30 osteoporotic vertebra fractures were treated with a computer-navigated kyphoplasty. The placement of the working needles in thoracic spine fractures was performed after acquiring an intraoperative three-dimensional data set. Fractures of the lumbar spine were treated using fluoroscopic three-dimensional navigation. During each procedure the operation time, the overall radiation time, and the DAP were documented. The data of the navigated operations were compared to a control group of consisting of 30 conventional balloon kyphoplasty procedures. In the conventional kyphoplasty group the average operation times for thoracic spine (ts) and lumbar spine (ls) were 61 and 57 minutes, respectively. The average radiation times were 175 and 165 seconds. The DAP applied to the patient was 1972 and 2105 cGy cm. The average operation times in the navigated group were 67 minutes in the ts and 62 minutes in the ls. The average radiation time was reduced significantly in the navigated group (99 seconds ts and 74 seconds ls). The DAP applied to the patient was also significantly lower (1245 cGy cm (ts) and 1318 cGy cm (ls)). The use of computer navigation systems in balloon kyphoplasty procedures reduces the radiation exposure of patients and surgeons significantly. The increased technical effort did not lead to a significant longer operation time. Hence, the use of computer navigation systems in balloon kyphoplasty procedures is recommended.

Cutting errors in total knee replacement: assessment by computer assisted surgery

The observed errors in the position of the implanted prosthesis can be due to a number of potential causes. One of these is the potential error during execution of the bone cuts. However, there is only minimal information on this in the current literature. The amount of cutting errors in 40 consecutive total knee replacements was reported. All the operations were done by the same surgeon. The amount of cutting error was measured by the use of computer navigation system. It was hypothesized that there was no difference in the amount of error between bone cut through the cutting slot (slotted cutting) and bone cut done on the surface of the cutting guide (open cutting). It was found that the average absolute cutting error was 1 masculine in the coronal plane and 1.4 masculine in the sagittal plane. Significantly more outlier (more than 3 masculine) was observed in the errors in the sagittal plane (P = 0.014, chi square test). Open cutting resulted in less error in the sagittal plane of the tibial cut when compared with slotted cutting (P = 0.031, Mann-Whitney U Test). This was attributed by the use of a thicker saw blade with higher stiffness in the open cutting method.