Computer-assisted Surgical Research Articles

The Use of Computer Navigation and Robotic Technology in Complex Total Knee Arthroplasty.

The potential benefits of computer-assisted surgical (CAS) navigation and robotic total knee arthroplasty (TKA) systems, such as increased reliability of restoring the mechanical axis, fewer outliers, more rapid hospital discharge, less physical therapy requirements, decreased blood loss, and decreased revision rates, have led to their application not only in primary cases but also in complex cases such as preoperative deformity and revision. Early evidence demonstrates that CAS navigation may help to improve alignment in complex cases of femoral and tibial deformity and in cases of femoral bowing. Data regarding deformity correction with robotic systems are similar to CAS navigation with regard to alignment, but are more limited. There are also scant data regarding revision cases and cases of previous intramedullary canal instrumentation. Concerns remain regarding cost, learning curves, and operative times. There are potential long-term cost savings associated with a decrease in revisions and readmissions that require additional investigation. Early evidence for the use of these emerging technologies for deformity correction and revision cases is promising, but their impact on long-term functional outcomes remains to be demonstrated. Additional well-designed comparative studies are warranted.

Linked kinematic knee balancing in unicompartmental knee arthroplasty

The traditional approach of restoring a neutral mechanical axis to the lower extremity during total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA) has long been favored due its consistency and reproducibility. The kinematic alignment approach, which accounts for the patient's natural knee alignment and is commonly a few degrees varus to the mechanical axis, has gained popularity in recent years as a technique which reestablishes a more anatomic alignment. Linked Anatomic Kinematic Arthroplasty (LAKA), an extension of the kinematic approach that employs computer-assisted surgical (CAS) navigation, can improve the accuracy and precision of kinematic measurements in unicompartmental knee arthroplasties. This article will describe the LAKA technique in UKA and review early clinical outcomes associated with this technique.

Osteotomy Planner: An open-source tool for osteotomy simulation.

There has been a recent emphasis in surgical science on supplementing surgical training outside of the Operating Room (OR). Combining simulation training with the current surgical apprenticeship enhances surgical skills in the OR, without increasing the time spent in the OR practicing. Computer-assisted surgical (CAS) planning consists of performing operative techniques virtually using three-dimensional (3D) computer-based models reconstructed from 3D cross-sectional imaging. The purpose of this paper is to present a CAS system to rehearse, visualize and quantify osteotomies, and demonstrate its usefulness in two different osteotomy surgical procedures, cranial vault reconstruction and femoral osteotomy. We found that the system could sufficiently simulate these two procedures. Our system takes advantage of the high-quality visualizations possible with 3DSlicer, as well as implements new infrastructure to allow for direct 3D interaction (cutting and positioning) with the bone models. We see the proposed osteotomy planner tool evolving towards incorporating different cutting templates to help depict several surgical scenarios, help 'trained' surgeons maintain operating skills, help rehearse a surgical sequence before heading to the OR, or even to help surgical planning for specific patient cases.

Haptic feedback improves surgeons' user experience and fracture reduction in facial trauma simulation.

Computer-assisted surgical (CAS) planning tools are available for craniofacial surgery, but are usually based on computer-aided design (CAD) tools that lack the ability to detect the collision of virtual objects (i.e., fractured bone segments). We developed a CAS system featuring a sense of touch (haptic) that enables surgeons to physically interact with individual, patient-specific anatomy and immerse in a three-dimensional virtual environment. In this study, we evaluated initial user experience with our novel system compared to an existing CAD system. Ten surgery resident trainees received a brief verbal introduction to both the haptic and CAD systems. Users simulated mandibular fracture reduction in three clinical cases within a 15 min time limit for each system and completed a questionnaire to assess their subjective experience. We compared standard landmarks and linear and angular measurements between the simulated results and the actual surgical outcome and found that haptic simulation results were not significantly different from actual postoperative outcomes. In contrast, CAD results significantly differed from both the haptic simulation and actual postoperative results. In addition to enabling a more accurate fracture repair, the haptic system provided a better user experience than the CAD system in terms of intuitiveness and self-reported quality of repair.

Clinical evaluation of computer-assisted surgical technique in the treatment of comminuted mandibular fractures

ObjectiveThe aim of this study is to establish the advantages and efficiency of computer-assisted surgical (CAS) technique in the treatment of comminuted mandibular fractures compared with conventional technique. MethodsIn the CAS group, 12 patients with comminuted mandibular fractures were treated with computer-assisted technique. Before surgery, a virtual reduction surgery was carried out in the software program MIMICS10.01. Then a reconstructed physical mandible was manufactured for preforming the titanium reconstruction plates. Based on the preoperative planning, the real surgery was carried out. Twelve cases with the same type of fracture treated with conventional technique were reviewed as the part of the control group. The clinical outcome of the surgery was evaluated in the two groups. ResultsCompared with the patients in the control group, in the case of 12 patients in the CAS group a decrease in the operation time and the amount of intraoperative bleeding as well as a superior outcome with respect to satisfaction, mandibular symmetry and postoperative level of opening the mouth were achieved. ConclusionThe CAS of preoperative 3-D planning and preformed plates is a clinically feasible tool for surgeons to improve the treatment of comminuted mandibular fractures.

Computer-Aided Trauma Simulation System With Haptic Feedback Is Easy and Fast for Oral-Maxillofacial Surgeons to Learn and Use

Computer-assisted surgical (CAS) planning tools have become widely available in craniomaxillofacial surgery, but are time consuming and often require professional technical assistance to simulate a case. An initial oral and maxillofacial (OM) surgical user experience was evaluated with a newly developed CAS system featuring a bimanual sense of touch (haptic). Three volunteer OM surgeons received a 5-minute verbal introduction to the use of a newly developed haptic-enabled planning system. The surgeons were instructed to simulate mandibular fracture reductions of 3 clinical cases, within a 15-minute time limit and without a time limit, and complete a questionnaire to assess their subjective experience with the system. Standard landmarks and linear and angular measurements between the simulated results and the actual surgical outcome were compared. After the 5-minute instruction, all 3 surgeons were able to use the system independently. The analysis of standardized anatomic measurements showed that the simulation results within a 15-minute time limit were not significantly different from those without a time limit. Mean differences between measurements of surgical and simulated fracture reductions were within current resolution limitations in collision detection, segmentation of computed tomographic scans, and haptic devices. All 3 surgeons reported that the system was easy to learn and use and that they would be comfortable integrating it into their daily clinical practice for trauma cases. A CAS system with a haptic interface that capitalizes on touch and force feedback experience similar to operative procedures is fast and easy for OM surgeons to learn and use.

Computer-Assisted Navigation for Dorsal Percutaneous Scaphoid Screw: Not a clinical study

To investigate a computer-assisted surgical (CAS) technique for antegrade insertion of percutaneous scaphoid screws and compare insertion time, accuracy, and radiation exposure with the traditional technique. We hypothesized that CAS navigation of dorsal percutaneous scaphoid screw placement would improve accuracy, reduce actual K-wire insertion time, and decrease radiation exposure to the operating room staff.

Neuronavigational guidance in craniofacial approaches for large (para)nasal tumors involving the anterior skull base and upper clival lesions

Objective Due to the destruction of osseous landmarks of the skull base or paranasal sinuses, the anatomical orientation during surgery of frontobasal or clival tumors with (para)nasal extension is often challenging. In this relation computer assisted surgical (CAS) guidance might be a useful tool. Here, we explored the use of CAS in an interdisciplinary setting. Methods The surgical series consists of 13 patients who underwent a lateral rhinotomy combined with a subfrontal craniotomy in case of significant intracranial tumor extension. The procedures were planned and assisted by advanced CAS techniques with image fusion of CT and MRI. Tumors included carcinomas (one case associated with an olfactory groove meningioma), esthesioneuroblastoma, chordoma, chondrosarcoma and ganglioglioma. Results The application of CAS in the combined approaches was both safe and reliable for delineation of tumors and identification of vital structures hidden or encased by the tumors. There was no perioperative 30-day mortality; however two patients died 5 weeks and 5 months after craniofacial tumor resection due to worsening medical conditions. The most common perioperative morbidity was postoperative wound complication in two cases. Tumors were either removed completely, or subtotal resection was achieved allowing targeted postoperative radiotherapy. Conclusion Craniofacial approaches with intraoperative neuronavigational guidance in a multidisciplinary setting allow safe resection of large tumors of the upper clivus and the paranasal sinuses involving the anterior skull base. Complex skull base surgery with the involvement of bony structures appears to be an ideal field for advanced navigation techniques given the lack of intraoperative shift of relevant structures.

Computer-assisted versus Manual Alignment in THA: A Probabilistic Approach to Range of Motion

Dislocation remains a major complication after THA, and range of motion before impingement is important in joint stability. Variability in implant alignment affects resultant range of motion. We used a probabilistic modeling approach to assess the effects of implant alignment variability based on manual and computer-assisted surgical (CAS) techniques on resultant range of motion after THA. We implemented a contact detection algorithm within a probabilistic analysis framework. The normally distributed alignment variables (mean +/- 1 standard deviation) were cup abduction (manual = 45 degrees +/- 7.6 degrees , CAS = 45 degrees +/- 5.7 degrees ), cup anteversion (manual = 20 degrees +/- 9.6 degrees , CAS = 20 degrees +/- 4.5 degrees ), and stem anteversion (manual and CAS = 10 degrees +/- 1.5 degrees ). The outcomes of the probabilistic analysis were range of motion distributions with 1% and 99% bounds. The upper bounds of motion for manual and CAS alignment were similar because bony impingement was the limiting factor. The lower bounds of range of motion were substantially different depending on the type of surgical alignment; manual alignment produced a smaller range of motion in 3% to 5% of cases. CAS implant alignment produced range of motion values above minimum acceptable levels in all cases simulated.

Comparative repeatability of guide-pin axis positioning in computer-assisted and manual femoral head resurfacing arthroplasty

The orientation of the femoral component in hip resurfacing arthroplasty affects the likelihood of loosening and fracture. Computer-assisted surgery has been shown to improve significantly the surgeon's ability to achieve a desired position and orientation; nevertheless, both bias and variability in positioning remain and can potentially be improved. The authors recently developed a computer-assisted surgical (CAS) technique to guide the placement of the pin used in femoral head resurfacing arthroplasty and showed that it produced significantly less variation than a typical manual technique in varus/valgus placement relative to a preoperatively determined surgical plan while taking a comparable amount of time. In the present study, the repeatability of both the CAS and manual techniques is evaluated in order to estimate the relative contributions to overall variability of surgical technique (CAS versus manual), surgeon experience (novice versus experienced), and other sources of variability (e.g. across specimens and across surgeons). This will enable further improvements in the accuracy of CAS techniques. Three residents/fellows new to femoral head resurfacing and three experienced hip arthroplasty surgeons performed 20-30 repetitions of each of the CAS and manual techniques on at least one of four cadaveric femur specimens. The CAS system had markedly better repeatability (1.2 degrees) in varus/valgus placement relative to the manual technique (2.8 degrees), slightly worse repeatability in version (4.4 degrees versus 3.2 degrees), markedly better repeatability in mid-neck placement (0.7 mm versus 2.5 mm), no significant dependence on surgeon skill level (in contrast to the manual technique), and took significantly less time (50 s versus 123 s). Proposed improvements to the version measurement process showed potential for reducing the standard deviation by almost two thirds. This study supports the use of CAS for femoral head resurfacing as it is quicker than the manual technique, independent of surgeon experience, and demonstrates improved repeatability.

Craniofacial Approach for Resection of Large Paranasal Tumors Involving the Anterior Skull Base and Upper Clivus Lesions Guided by Navigation Techniques

Frontobasal or clival tumors with paranasal extension often need a combined ENT and neurosurgical approach for complete tumor resection. With regard to the extent of tumor resection and procedure-related morbidity, most pathologies in these regions are difficult to treat. Due to destruction of osseous landmarks of the skull base or paranasal sinuses, the anatomical orientation during surgery is also impeded. In this setting, computer-assisted surgical (CAS) guidance provides a useful tool. We report on a series of patients operated on by craniofacial approaches guided by CAS techniques. Thirteen patients were included in this surgical series. The surgical approach consisted of a lateral rhinotomy combined with a subfrontal craniotomy when necessary. The procedures were planned and assisted by advanced CAS techniques with image fusion of CT and MRI (Medtronic Stealth Station and BrainLAB Vector Vision). Tumors included chordomas, esthesioneuroblastomas, ganglioglioma, and carcinomas (in 1 case associated with an olfactory groove meningioma). Lateral rhinotomy was performed by the ENT surgeon and conjoint tumor removal with dural repair was performed together with the neurosurgeon in all cases. In 4 cases an additional frontal craniotomy was performed. The application of CAS in combined approaches appeared to be safe and reliable for identification of tumor borders or vital structures hidden or encased by the tumors. There was no mortality in our series. A secondary plastic procedure was performed in 2 patients after extensive tumor resection. There were no new permanent neurological deficits. Tumors were either removed completely, or subtotal resection was achieved allowing targeted postoperative radiotherapy. There were 2 tumor recurrences (esthesioneuroblastoma and paranasal squamous cell carcinoma) after total tumor resection and 1 recurrence after subtotal resection of a grade 2 chondrosarcoma.

Craniofacial Approach for Resection of Large Paranasal Tumors Involving the Anterior Skull Base and Upper Clivus Lesions Guided by Navigation Techniques

Frontobasal or clival tumors with paranasal extension often need a combined ENT and neurosurgical approach for complete tumor resection. With regard to the extent of tumor resection and procedure-related morbidity, most pathologies in these regions are difficult to treat. Due to destruction of osseous landmarks of the skull base or paranasal sinuses, the anatomical orientation during surgery is also impeded. In this setting, computer-assisted surgical (CAS) guidance provides a useful tool. We report on a series of patients operated on by craniofacial approaches guided by CAS techniques. Thirteen patients were included in this surgical series. The surgical approach consisted of a lateral rhinotomy combined with a subfrontal craniotomy when necessary. The procedures were planned and assisted by advanced CAS techniques with image fusion of CT and MRI (Medtronic Stealth Station and BrainLAB Vector Vision). Tumors included chordomas, esthesioneuroblastomas, ganglioglioma, and carcinomas (in 1 case associated with an olfactory groove meningioma). Lateral rhinotomy was performed by the ENT surgeon and conjoint tumor removal with dural repair was performed together with the neurosurgeon in all cases. In 4 cases an additional frontal craniotomy was performed. The application of CAS in combined approaches appeared to be safe and reliable for identification of tumor borders or vital structures hidden or encased by the tumors. There was no mortality in our series. A secondary plastic procedure was performed in 2 patients after extensive tumor resection. There were no new permanent neurological deficits. Tumors were either removed completely, or subtotal resection was achieved allowing targeted postoperative radiotherapy. There were 2 tumor recurrences (esthesioneuroblastoma and paranasal squamous cell carcinoma) after total tumor resection and 1 recurrence after subtotal resection of a grade 2 chondrosarcoma.

Computer-assisted femoral head resurfacing

Femoral head resurfacing is re-emerging as a surgical option for younger patients who are not yet candidates for total hip replacement. However, this procedure is more difficult than total hip replacement, and the mechanical jigs typically used to align the implant produce significant variability in implant placement and take a significant amount of time to position properly. We propose that a computer-assisted surgical (CAS) technique could reduce implant variability with little or no increase in operative time. We describe a new CAS technique for this procedure and demonstrate in a cadaver study of five paired femurs that the CAS technique in the hands of a novice surgeon markedly reduced the varus/valgus variability of the implant relative to the pre-operative plan (2° standard deviation for CAS versus 5° for a mechanical jig operated by an expert surgeon). We also show that the mechanical jig resulted in significantly retroverted implant placement. There was no significant difference in operative time between the two techniques.

Craniofacial Computerassisted Surgical Planning and Simulation

Computer-assisted planning and simulation of craniofacial surgery has progressed from development, through validation, and into clinical use. CT scans are transferred from the radiology department to a graphics workstation in the surgeon's office or laboratory, where data postprocessing and visualization for anatomic evaluation and surgical simulation are performed. Quantitative and qualitative comparative analyses between the plan/simulation and the actual postoperative result provide the feedback that validates or refutes the preoperative assessment and simulated intervention. The optimum surgical solution can be chosen from many possibilities. Interactive computer-assisted surgical simulation is also useful for morbidity-free training of inexperienced surgeons.