Accuracy of pedicle localization using a 3D ultrasound navigator on vertebral phantoms for posterior spinal surgery

Severe adolescent idiopathic scoliosis (AIS) requires surgery to halt curve progression. Accurate insertion of pedicle screws is important. This study reports a newly developed 3D ultrasound (3DUS) to localize pedicles intraoperatively and register a pre-op 3D vertebral model to the surface to be displayed for navigation. The objective was to determine speed of the custom 3DUS navigator and accuracy of pedicle probe placement. The developed 3DUS navigator integrated an ultrasound scanner with motion capture cameras. Two adolescent 3D printed spine models T2-T8 and T7-T11 were modified to include pedicle holes with known trajectory and be mounted on a high precision LEGO pegboard in a water bath for imaging. Calibration of the motion cameras and the 3DUS were conducted prior to the study. A total of 27 scans from T3 to T11 vertebrae with 3 individual scans were performed to validate the repeatability. Three accuracy tests that varied vertebral a) orientation, b) position and c) a combination of location and orientation were completed. Based on all experiments, the acquisition-to-display time was 18.9±3.1s. The repeatability of the trajectory error and positional error were 0.5±0.2° and 0.3±0.1mm, respectively. The a) center orientation, b) position and c) orientation/position on trajectory and positional error were for a) 1.4±0.9° and 0.5±0.4mm, b) 1.4±0.8° and 0.3±0.3mm and c) 2.0±0.8° and 0.5±0.5mm, respectively. These results demonstrated that a high precision real-time 3DUS navigator for screw placement in scoliosis surgery is feasible. The next step will study the effect of surrounding soft tissues on navigation accuracy.

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In Situ Visualization for 3D Ultrasound-Guided Interventions with Augmented Reality Headset

Bioengineering ◽

10.3390/bioengineering8100131 ◽

2021 ◽

Vol 8 (10) ◽

pp. 131

Author(s):

Nadia Cattari ◽

Sara Condino ◽

Fabrizio Cutolo ◽

Mauro Ferrari ◽

Vincenzo Ferrari

Keyword(s):

Augmented Reality ◽

Ultrasound Imaging ◽

High Precision ◽

Soft Tissues ◽

Imaging System ◽

3D Ultrasound ◽

Integrated System ◽

Head Mounted Display ◽

Manual Tasks

Augmented Reality (AR) headsets have become the most ergonomic and efficient visualization devices to support complex manual tasks performed under direct vision. Their ability to provide hands-free interaction with the augmented scene makes them perfect for manual procedures such as surgery. This study demonstrates the reliability of an AR head-mounted display (HMD), conceived for surgical guidance, in navigating in-depth high-precision manual tasks guided by a 3D ultrasound imaging system. The integration between the AR visualization system and the ultrasound imaging system provides the surgeon with real-time intra-operative information on unexposed soft tissues that are spatially registered with the surrounding anatomic structures. The efficacy of the AR guiding system was quantitatively assessed with an in vitro study simulating a biopsy intervention aimed at determining the level of accuracy achievable. In the experiments, 10 subjects were asked to perform the biopsy on four spherical lesions of decreasing sizes (10, 7, 5, and 3 mm). The experimental results showed that 80% of the subjects were able to successfully perform the biopsy on the 5 mm lesion, with a 2.5 mm system accuracy. The results confirmed that the proposed integrated system can be used for navigation during in-depth high-precision manual tasks.

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Custom-Made 3D-Printed Implants as Novel Approach to Reconstructive Surgery after Oncologic Resection in Pediatric Patients

Journal of Clinical Medicine ◽

10.3390/jcm10051056 ◽

2021 ◽

Vol 10 (5) ◽

pp. 1056

Author(s):

Giovanni Beltrami ◽

Gabriele Ristori ◽

Anna Maria Nucci ◽

Alberto Galeotti ◽

Angela Tamburini ◽

...

Keyword(s):

Pediatric Patients ◽

Soft Tissues ◽

Lower Limbs ◽

Host Bone ◽

Limb Salvage Surgery ◽

Musculoskeletal Tumor ◽

Musculoskeletal Tumor Society ◽

Custom Made ◽

3D Printed

Recently, custom-made 3D-printed prostheses have been introduced for limb salvage surgery in adult patients, but their use has not been described in pediatric patients. A series of 11 pediatric patients (mean age 10.8 years; range 2–13) with skeletal tumors treated with custom-made implants for the reconstruction of bony defects is described. Patients were followed up every 3 months. Functional results were evaluated by the Musculoskeletal Tumor Society Score (MSTS) for upper and lower limbs. The mean follow-up was 25.7 months (range 14–44). Three patients died after a mean of 19.3 months postoperatively—two because of disease progression and the other from a previous malignancy. Three patients experienced complications related to soft tissues. One patient required device removal, debridement, and antibiotic pearls for postoperative infection. Partial osseointegration between grafts and host bone was observed within a mean of 4 months. At the final follow-up, mean MSTS score was 75%. 3D prostheses may yield biological advantages due to possible integration with the host bone and also through the use of vascularized flaps. Further research is warranted.

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Hybrid Spine Simulator Prototype for X-ray Free Pedicle Screws Fixation Training

Applied Sciences ◽

10.3390/app11031038 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1038

Author(s):

Sara Condino ◽

Giuseppe Turini ◽

Virginia Mamone ◽

Paolo Domenico Parchi ◽

Vincenzo Ferrari

Keyword(s):

Augmented Reality ◽

Low Cost ◽

Lumbar Vertebrae ◽

Pedicle Screws ◽

Simulation Software ◽

Patient Specific ◽

Innovative Strategy ◽

X Ray ◽

3D Printed ◽

Harmful Radiation

Simulation for surgical training is increasingly being considered a valuable addition to traditional teaching methods. 3D-printed physical simulators can be used for preoperative planning and rehearsal in spine surgery to improve surgical workflows and postoperative patient outcomes. This paper proposes an innovative strategy to build a hybrid simulation platform for training of pedicle screws fixation: the proposed method combines 3D-printed patient-specific spine models with augmented reality functionalities and virtual X-ray visualization, thus avoiding any exposure to harmful radiation during the simulation. Software functionalities are implemented by using a low-cost tracking strategy based on fiducial marker detection. Quantitative tests demonstrate the accuracy of the method to track the vertebral model and surgical tools, and to coherently visualize them in either the augmented reality or virtual fluoroscopic modalities. The obtained results encourage further research and clinical validation towards the use of the simulator as an effective tool for training in pedicle screws insertion in lumbar vertebrae.

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Slowly cycling Rho kinase-dependent actomyosin cross-bridge “slippage” explains intrinsic high compliance of detrusor smooth muscle

AJP Renal Physiology ◽

10.1152/ajprenal.00633.2016 ◽

2017 ◽

Vol 313 (1) ◽

pp. F126-F134 ◽

Cited By ~ 4

Author(s):

Christopher J. Neal ◽

Jia B. Lin ◽

Tanner Hurley ◽

Amy S. Miner ◽

John E. Speich ◽

...

Keyword(s):

Smooth Muscle ◽

Soft Tissues ◽

Plastic Material ◽

Rho Kinase ◽

Detrusor Smooth Muscle ◽

Display Time ◽

Protein Activation ◽

Cross Bridge ◽

Cross Bridges ◽

Dependent Viscosity

Biological soft tissues are viscoelastic because they display time-independent pseudoelasticity and time-dependent viscosity. However, there is evidence that the bladder may also display plasticity, defined as an increase in strain that is unrecoverable unless work is done by the muscle. In the present study, an electronic lever was used to induce controlled changes in stress and strain to determine whether rabbit detrusor smooth muscle (rDSM) is best described as viscoelastic or viscoelastic plastic. Using sequential ramp loading and unloading cycles, stress-strain and stiffness-stress analyses revealed that rDSM displayed reversible viscoelasticity, and that the viscous component was responsible for establishing a high stiffness at low stresses that increased only modestly with increasing stress compared with the large increase produced when the viscosity was absent and only pseudoelasticity governed tissue behavior. The study also revealed that rDSM underwent softening correlating with plastic deformation and creep that was reversed slowly when tissues were incubated in a Ca2+-containing solution. Together, the data support a model of DSM as a viscoelastic-plastic material, with the plasticity resulting from motor protein activation. This model explains the mechanism of intrinsic bladder compliance as “slipping” cross bridges, predicts that wall tension is dependent not only on vesicle pressure and radius but also on actomyosin cross-bridge activity, and identifies a novel molecular target for compliance regulation, both physiologically and therapeutically.

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Sublaminar fixation versus hooks and pedicle screws in scoliosis surgery for Marfan syndrome

Journal of Craniovertebral Junction and Spine ◽

10.4103/jcvjs.jcvjs_12_20 ◽

2020 ◽

Vol 11 (1) ◽

pp. 26

Author(s):

Alessandro Rava ◽

Eugenio Dema ◽

Matteo Palmisani ◽

Rosa Palmisani ◽

Stefano Cervellati ◽

...

Keyword(s):

Marfan Syndrome ◽

Pedicle Screws ◽

Scoliosis Surgery

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Fast And Simple Automatic 3D Ultrasound Probe Calibration Based On 3D Printed Phantom And An Untracked Marker

2018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC) ◽

10.1109/embc.2018.8512406 ◽

2018 ◽

Cited By ~ 2

Author(s):

Jun Shen ◽

Nabil Zemiti ◽

Jean-Louis Dillenseger ◽

Philippe Poignet

Keyword(s):

3D Ultrasound ◽

Ultrasound Probe ◽

3D Printed ◽

Probe Calibration

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Wearable Augmented Reality Platform for Aiding Complex 3D Trajectory Tracing

Sensors ◽

10.3390/s20061612 ◽

2020 ◽

Vol 20 (6) ◽

pp. 1612 ◽

Cited By ~ 3

Author(s):

Sara Condino ◽

Benish Fida ◽

Marina Carbone ◽

Laura Cercenelli ◽

Giovanni Badiali ◽

...

Keyword(s):

Augmented Reality ◽

High Precision ◽

Ad Hoc ◽

User Study ◽

Peripersonal Space ◽

Planar Structures ◽

3D Printed ◽

Quantitative Results ◽

Manual Tasks ◽

Wearable Augmented Reality

Augmented reality (AR) Head-Mounted Displays (HMDs) are emerging as the most efficient output medium to support manual tasks performed under direct vision. Despite that, technological and human-factor limitations still hinder their routine use for aiding high-precision manual tasks in the peripersonal space. To overcome such limitations, in this work, we show the results of a user study aimed to validate qualitatively and quantitatively a recently developed AR platform specifically conceived for guiding complex 3D trajectory tracing tasks. The AR platform comprises a new-concept AR video see-through (VST) HMD and a dedicated software framework for the effective deployment of the AR application. In the experiments, the subjects were asked to perform 3D trajectory tracing tasks on 3D-printed replica of planar structures or more elaborated bony anatomies. The accuracy of the trajectories traced by the subjects was evaluated by using templates designed ad hoc to match the surface of the phantoms. The quantitative results suggest that the AR platform could be used to guide high-precision tasks: on average more than 94% of the traced trajectories stayed within an error margin lower than 1 mm. The results confirm that the proposed AR platform will boost the profitable adoption of AR HMDs to guide high precision manual tasks in the peripersonal space.

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Comparative analysis of pedicle screw versus hybrid instrumentation in adolescent idiopathic scoliosis surgery

Journal of Neurosciences in Rural Practice ◽

10.4103/0976-3147.185510 ◽

2016 ◽

Vol 7 (04) ◽

pp. 550-553 ◽

Cited By ~ 4

Author(s):

Sohail Rafi ◽

Naseem Munshi ◽

Asad Abbas ◽

Rabia Hassan Shaikh ◽

Imtiaz Hashmi

Keyword(s):

Adolescent Idiopathic Scoliosis ◽

Idiopathic Scoliosis ◽

Cobb Angle ◽

Pedicle Screw ◽

Pedicle Screws ◽

Scoliosis Surgery ◽

Hybrid Instrumentation ◽

System Versus ◽

Cobb’S Angle

ABSTRACT Introduction: Adolescent idiopathic scoliosis is the most common type of scoliosis. A Cobb angle of 50° will progress beyond the age of spinal maturity. Surgery over bracing is advised at a Cobb angle above or equal to 50°. The aim of surgery is to bring the Cobb angle down below 50° to prevent reprogression as well as improve the quality of life. The objective of the study is to analyze the efficacy and significance in lifestyle improvement of pedicle screw-only fixation system versus the more common hybrid instrumentation system used for the surgical treatment of adolescent idiopathic scoliosis. Materials and Methods: A prospective cohort study was conducted involving two groups of patients were included in the study. One group was operated with pedicle screw-only method while the other with hybrid instrumentation system. The pre- and post-operative Cobb’s angles were taken across a follow-up of 4 years. An SRS-30 questionnaire was given in a yearly follow-up to assess the lifestyle improvement of the patient. Results: Pedicle screw-only method was significantly more effective in reducing Cobb’s angle (P = 0.0487). It was showed less loss of correction (P = 0.009) pedicle screw-only surgery was also better at reducing thoracic curves (P = 0.001). There seemed a better recovery time with pedicle screw surgery (P = 0.003). Conclusion: Pedicle screws are more effective and durable than hybrid systems at when treating adolescent idiopathic scoliosis.

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Efficacy and safety for combination of t-EMG with O-arm assisted pedicle screw placement in neurofibromatosis type I scoliosis surgery

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-021-02882-9 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Xiexiang Shao ◽

Zifang Huang ◽

Jingfan Yang ◽

Yaolong Deng ◽

Junlin Yang ◽

...

Keyword(s):

Pedicle Screw ◽

Pedicle Screws ◽

Neurofibromatosis Type ◽

Screw Placement ◽

Type I ◽

Scoliosis Surgery ◽

Neurofibromatosis Type I ◽

Efficacy And Safety ◽

Pedicle Screw Placement ◽

Channel Classification

Abstract Background Due to the characteristics of neurofibromatosis type I (NF-1) scoliosis, the precise placement of pedicle screws still remains to be a challenge. Triggered screw electromyography (t-EMG) has been proved to exhibit high sensitivity to identify mal-positioned pedicle screws, but no previous study assessed the combination of t-EMG with O-arm-assisted pedicle screw placement in NF-1 scoliosis surgery. Objective To evaluate efficacy and safety for combination of t-EMG with O-arm-assisted pedicle screw placement in NF-1 scoliosis surgery. Materials and methods From March 2018 to April 2020, sixty-five NF-1 scoliosis patients underwent t-EMG and O-arm-assisted pedicle screw fixation were retrospectively reviewed. The channel classification system was applied to classify the pedicle morphology based on pedicle width measurement by preoperative computed tomography scans. The minimal t-EMG threshold for screw path inspection was used as 8 mA, and operative screw redirection was also recorded. All pedicle screws were verified using a second intraoperative O-arm scan. The correlation between demographic and clinical data with amplitude of t-EMG were also analyzed. Results A total of 652 pedicle screws (T10-S1) in 65 patients were analyzed. The incidence of an absent pedicle (channel classification type C or D morphology) was 150 (23%). Overall, abnormal t-EMG threshold was identified in 26 patients with 48 screws (7.4%), while 16 out of the 48 screws were classified as G0, 14 out of the 48 screws were classified as G1, and 18 out of the 48 screws were classified as G2. The screw redirection rate was 2.8% (18/652). It showed that t-EMG stimulation detected 3 unacceptable mal-positioned screws in 2 patients (G2) which were missed by O-arm scan. No screw-related neurological or vascular complications were observed. Conclusions Combination of t-EMG with O-arm-assisted pedicle screw placement was demonstrated to be a safe and effective method in NF-1 scoliosis surgery. The t-EMG could contribute to detecting the rupture of the medial wall which might be missed by O-arm scan. Combination of t-EMG with O-arm could be recommended for routine use of screw insertion in NF-1 scoliosis surgery.

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