The Use of Robotics Coupled With Navigation for Pediatric Congenital Spine Deformity

Background: Spinal instrumentation in children with congenital spine deformity poses challenges to the surgeon, given the small patient size and the anomalous anatomy often encountered. Purpose: We aimed to investigate the accuracy of screw placement when robotics coupled with real-time navigation was used for surgical treatment of pediatric congenital spine deformity at 1 institution. Methods: We conducted a retrospective search of our institution’s database for all patients younger than 18 years of age with congenital spine deformity who were treated with the robotics surgical platform coupled with navigation between June 2019 and December 2020. We recorded data on demographics, location and type of anomaly, procedure performed, and intraoperative variables related to robotics and navigation. We reviewed the images of patients who had intraoperative 3-dimensional imaging or postoperative computed tomographic scans to determine the accuracy of screw placement using the Gertzbein-Robbins scale. Results: In 14 patients identified, a total of 95 screws were attempted, with 94 successfully placed using robotics coupled with navigation. There were no noted screw-related complications (neurologic or visceral) and no return to the operating room for screw malposition. Conclusion: Patients with congenital spine deformity present potentially unique challenges due to variant anatomy. This retrospective series suggests that robotics coupled with navigation for congenital spine deformity correction in the pediatric population may aid in accurate screw placement and reduce complication rates. More rigorous study is warranted.

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Bilateral use of the vertical expandable prosthetic titanium rib attached to the pelvis: a novel treatment for scoliosis in the growing spine

Journal of Neurosurgery Spine ◽

10.3171/2008.12.spine08427 ◽

2009 ◽

Vol 10 (4) ◽

pp. 287-292 ◽

Cited By ~ 26

Author(s):

Amer F. Samdani ◽

Ashish Ranade ◽

Henry J. Dolch ◽

Reed Williams ◽

Tricia St. Hilaire ◽

...

Keyword(s):

Cobb Angle ◽

Early Onset ◽

Deformity Correction ◽

Early Onset Scoliosis ◽

Spine Deformity ◽

Complication Rates ◽

Novel Device ◽

Age At Surgery ◽

Growing Spine

Object Few options exist for the treatment of severe, early onset scoliosis. Goals of treatment include stabilizing curve progression while allowing for normal spine, chest, and lung growth. The vertical expandable prosthetic titanium rib (VEPTR) is a novel device designed to control the spine deformity while permitting lung and spine growth. In this paper the authors report their experience with using bilateral VEPTRs from the ribs to the pelvis for children with severe, early onset scoliosis. Methods Eleven children were identified who had been treated with bilateral VEPTRs from the ribs to the pelvis. The authors conducted a retrospective review and collected the following data: clinical diagnosis, age at surgery, number of lengthening procedures, and complications. In addition, pre- and postoperative radiographs were reviewed to measure maximum Cobb angle (both thoracic and lumbar), thoracic height, total spine height as measured from T-1 to S-1, thoracic kyphosis (T2–12), and lumbar lordosis (L1–S1). Results The average patient age at surgery was 71 months; the mean preoperative thoracic Cobb angle was 81.7°. This angle was corrected to 50.6° immediately postoperatively, and this correction was maintained; at the most recent follow-up the curves averaged 58°. Similarly, the preoperative kyphosis (T2–12) angle measured 43° preoperatively, 23° immediately postoperatively, and 37° at the most recent follow-up evaluation. The patients underwent a total of 41 lengthening procedures (average 3.7 lengthening procedures per patient), and overall spine length increased from 23.1 cm preoperatively, to 27.3 cm immediately postoperatively, to 29.4 cm at the final follow-up (an average of 25 months). Four (36.4%) of the 11 patients experienced complications. Conclusions The VEPTR offers a viable treatment option for children with severe, early onset scoliosis. It achieves and maintains spinal deformity correction, while allowing for continued spine and chest-wall growth. Complication rates are similar to those reported for other growing systems.

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Male sex may not be associated with worse outcomes in primary all-posterior adult spinal deformity surgery: a multicenter analysis

Neurosurgical FOCUS ◽

10.3171/2017.9.focus17475 ◽

2017 ◽

Vol 43 (6) ◽

pp. E9 ◽

Cited By ~ 4

Author(s):

David B. Bumpass ◽

Lawrence G. Lenke ◽

Jeffrey L. Gum ◽

Christopher I. Shaffrey ◽

Justin S. Smith ◽

...

Keyword(s):

Sex Differences ◽

Spinal Deformity ◽

Operative Time ◽

Adult Spinal Deformity ◽

Deformity Correction ◽

Spine Deformity ◽

Complication Rates ◽

Female Patients ◽

Male Patients

OBJECTIVEAdolescent spine deformity studies have shown that male patients require longer surgery and have greater estimated blood loss (EBL) and complications compared with female patients. No studies exist to support this relationship in adult spinal deformity (ASD). The purpose of this study was to investigate associations between sex and complications, deformity correction, and health-related quality of life (HRQOL) in patients with ASD. It was hypothesized that male ASD patients would have greater EBL, longer surgery, and more complications than female ASD patients.METHODSA multicenter ASD cohort was retrospectively queried for patients who underwent primary posterior-only instrumented fusions with a minimum of 5 levels fused. The minimum follow-up was 2 years. Primary outcomes were EBL, operative time, intra-, peri-, and postoperative complications, radiographic correction, and HRQOL outcomes (Oswestry Disability Index, SF-36, and Scoliosis Research Society-22r Questionnaire). Poisson multivariate regression was used to control for age, comorbidities, and levels fused.RESULTSNinety male and 319 female patients met the inclusion criteria. Male patients had significantly greater mean EBL (2373 ml vs 1829 ml, p = 0.01). The mean operative time, transfusion requirements, and final radiographic measurements did not differ between sexes. Similarly, changes in HRQOL showed no significant differences. Finally, there were no sex differences in the incidence of complications (total, major, or minor) at any time point after controlling for age, body mass index, comorbidities, and levels fused.CONCLUSIONSDespite higher EBL, male ASD patients did not experience more complications or require less deformity correction at the 2-year follow-up. HRQOL scores similarly showed no sex differences. These findings differ from adolescent deformity studies, and surgeons can counsel patients that sex is unlikely to influence the outcomes and complication rates of primary all-posterior ASD surgery.

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Facet Violation With Percutaneous Pedicle Screw Placement: Impact of 3D Navigation and Facet Orientation

HSS Journal ® ◽

10.1177/15563316211026324 ◽

2021 ◽

pp. 155633162110263

Author(s):

Ting Cong ◽

Ahilan Sivaganesan ◽

Christopher M. Mikhail ◽

Avani S. Vaishnav ◽

James Dowdell ◽

...

Keyword(s):

Pedicle Screw ◽

Screw Placement ◽

Radiographic Measurement ◽

Pedicle Screw Placement ◽

3D Navigation ◽

3 Dimensional ◽

Computed Tomographic ◽

Percutaneous Pedicle Screw ◽

Facet Orientation ◽

Placement Accuracy

Background: The gold standard for percutaneous pedicle screw placement is 2-dimensional (2D) fluoroscopy. Data are sparse on the accuracy of 3-dimensional (3D) navigation percutaneous screw placement in minimally invasive spine procedures. Objective: We sought to compare a single surgeon’s percutaneous pedicle screw placement accuracy using 2D fluoroscopy versus 3D navigation, as well as to investigate the effect of facet orientation on facet violation when using 2D fluoroscopy. Methods: We conducted a retrospective radiographic study of consecutive cohort of patients who underwent percutaneous lumbar instrumentation using either 2D fluoroscopy or 3D navigation. All procedures were performed by a single surgeon at 2 academic institutions between 2011 and 2018. Radiographic measurement of screw accuracy was assessed using a postoperative computed tomographic scan. The primary outcome was facet violation, and secondary outcomes were endplate/tip breaches, the Gertzbein-Robbins classification for cortical breaches, and the Simplified Screw Accuracy grade. Statistical comparisons were made between screws placed using 2D fluoroscopy versus 3D navigation. Axial facet angles were also measured to correlate with facet violation rates. Results: In the 138 patients included, 376 screws were placed with fluoroscopy and 193 with navigation. Superior (unfused) level facet violation was higher with 2D fluoroscopy than with 3D navigation (9% vs 0.5%), which comprises the main cause for poor screw placement. Axial facet angles exceeding 45° at L4 and 60° at L5 were correlated with facet violations. Conclusion: This retrospective study found that 3D navigation is associated with lower facet violation rates in percutaneous lumbar pedicle screw placement when compared with 2D fluoroscopy. These findings suggest that 3D navigation may be of particular value when facet joints are coronally oriented.

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Clinical accuracy and initial experience with augmented reality–assisted pedicle screw placement: the first 205 screws

Journal of Neurosurgery Spine ◽

10.3171/2021.2.spine202097 ◽

2021 ◽

pp. 1-7

Author(s):

Ann Liu ◽

Yike Jin ◽

Ethan Cottrill ◽

Majid Khan ◽

Erick Westbroek ◽

...

Keyword(s):

Augmented Reality ◽

Pedicle Screw ◽

Spinal Instrumentation ◽

Deformity Correction ◽

Pedicle Screws ◽

Screw Placement ◽

Pedicle Screw Placement ◽

Lower Extremity Weakness ◽

Head Mounted Display ◽

Clinical Accuracy

OBJECTIVE Augmented reality (AR) is a novel technology which, when applied to spine surgery, offers the potential for efficient, safe, and accurate placement of spinal instrumentation. The authors report the accuracy of the first 205 pedicle screws consecutively placed at their institution by using AR assistance with a unique head-mounted display (HMD) navigation system. METHODS A retrospective review was performed of the first 28 consecutive patients who underwent AR-assisted pedicle screw placement in the thoracic, lumbar, and/or sacral spine at the authors’ institution. Clinical accuracy for each pedicle screw was graded using the Gertzbein-Robbins scale by an independent neuroradiologist working in a blinded fashion. RESULTS Twenty-eight consecutive patients underwent thoracic, lumbar, or sacral pedicle screw placement with AR assistance. The median age at the time of surgery was 62.5 (IQR 13.8) years and the median body mass index was 31 (IQR 8.6) kg/m2. Indications for surgery included degenerative disease (n = 12, 43%); deformity correction (n = 12, 43%); tumor (n = 3, 11%); and trauma (n = 1, 4%). The majority of patients (n = 26, 93%) presented with low-back pain, 19 (68%) patients presented with radicular leg pain, and 10 (36%) patients had documented lower extremity weakness. A total of 205 screws were consecutively placed, with 112 (55%) placed in the lumbar spine, 67 (33%) in the thoracic spine, and 26 (13%) at S1. Screw placement accuracy was 98.5% for thoracic screws, 97.8% for lumbar/S1 screws, and 98.0% overall. CONCLUSIONS AR depicted through a unique HMD is a novel and clinically accurate technology for the navigated insertion of pedicle screws. The authors describe the first 205 AR-assisted thoracic, lumbar, and sacral pedicle screws consecutively placed at their institution with an accuracy of 98.0% as determined by a Gertzbein-Robbins grade of A or B.

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TREATMENT OF SEVERE SPINAL DEFORMATIONS IN CHILDREN WITH IDIOPATHIC SCOLIOSIS USING HALO-GRAVITY TRACTION

Wiadomości Lekarskie ◽

10.36740/wlek202010107 ◽

2020 ◽

Vol 73 (10) ◽

pp. 2144-2149

Author(s):

Valentyn A. Rohozynskyi ◽

Anatolii F. Levytskyi ◽

Mykola M. Dolianytskyi ◽

Irina M. Benzar

Keyword(s):

Spinal Cord ◽

Comparative Analysis ◽

Vertebral Column ◽

Spinal Instrumentation ◽

Deformity Correction ◽

Second Step ◽

Vertebral Column Resection ◽

3 Dimensional ◽

One Step ◽

Surgical Treatments

The aim: To chose the best way treatment and achievement of 3-dimensional spinal correction in order to maximize its parameters to the physiological norms is a choice of the optimal surgical severe scoliotic spinal deformity correction technology. Materials and methods: Performed surgical treatments to 60 children of two patient’s groups, that were under surgical treatment for severe scoliotic spinal deformations with preliminary used halo-gravity traction and one-step correction; to establish an effective and safe protocol of the treatment for children with severe scoliotic spinal deformations (>100°). The results comparative analysis of 60 patients with severe scoliotic spinal deformations, with a two-step surgery treatments (first step – halo-gravity traction and second step – correcting spinal instrumentation) and patients with one-step correction. Patients were divided into 2 groups with 30 children in each of them. The first group treated with preoperatively HGT (halo-gravity traction) and after that a spinal instrumentation together with osteotomies (3-4 levels by Ponte; VCR (vertebral column resection) osteotomy 1 level) were performed. The second group – performed one-step spinal instrumentation with osteotomies (3-4 levels by Ponte; VCR osteotomy 1 level). Results: One-step implanted construction in children with severe scoliotic spinal deformations, compare to HGT treatment that were carried out in stages – is increasing the danger of neurological deficiency by 17%, HGT allows to make more corrections and to adjust spinal cord for the next correction treatment. . Conclusions: Halo-gravity traction as a first stage of severe scoliotic spinal deformations treatment allows to increase the mobility of the vertebral column and to adjust spinal cord step by step for the next correction treatment.

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Equivalence of fusion rates after rigid internal fixation of the occiput to C-2 with or without C-1 instrumentation

Journal of Neurosurgery Pediatrics ◽

10.3171/2009.10.peds09296 ◽

2010 ◽

Vol 5 (4) ◽

pp. 380-384 ◽

Cited By ~ 38

Author(s):

Todd C. Hankinson ◽

Anthony M. Avellino ◽

David Harter ◽

Andrew Jea ◽

Sean Lew ◽

...

Keyword(s):

Perioperative Complications ◽

Pediatric Population ◽

Spinal Instrumentation ◽

Fusion Rate ◽

Atlantoaxial Instability ◽

Complication Rates ◽

Group 3 ◽

Group 2 ◽

Lost To Follow Up ◽

Group 1

Object The object of this study was to assess a multiinstitutional experience with pediatric occipitocervical constructs to determine whether a difference exists between the fusion and complication rates of constructs with or without direct C-1 instrumentation. Methods Seventy-seven cases of occiput-C2 instrumentation and fusion, performed at 9 children's hospitals, were retrospectively analyzed. Entry criteria included atlantooccipital instability with or without atlantoaxial instability. Any case involving subaxial instability was excluded. Constructs were divided into 3 groups based on the characteristics of the anchoring spinal instrumentation: Group 1, C-2 instrumentation; Group 2, C-1 and C-2 instrumentation without transarticular screw (TAS) placement; and Group 3, any TAS placement. Groups were compared based on rates of fusion and perioperative complications. Results Group 1 consisted of 16 patients (20.8%) and had a 100% rate of radiographically demonstrated fusion. Group 2 included 22 patients (28.6%), and a 100% fusion rate was achieved, although 2 cases were lost to follow-up before documented fusion. Group 3 included 39 patients (50.6%) and demonstrated a 100% radiographic fusion rate. Complication rates were 12.5, 13.7, and 5.1%, respectively. There were 3 vertebral artery injuries, 1 (4.5%) in Group 2 and 2 (5.1%) in Group 3. Conclusions High fusion rates and low complication rates were achieved with each configuration examined. There was no difference in fusion rates between the group without (Group 1) and those with (Groups 2 and 3) C-1 instrumentation. These findings indicated that in the pediatric population, excellent occipitocervical fusion rates can be accomplished without directly instrumenting C-1.

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Evaluation of robot-guided minimally invasive implantation of 2067 pedicle screws

Neurosurgical FOCUS ◽

10.3171/2017.2.focus16552 ◽

2017 ◽

Vol 42 (5) ◽

pp. E11 ◽

Cited By ~ 36

Author(s):

Naureen Keric ◽

Christian Doenitz ◽

Amer Haj ◽

Izabela Rachwal-Czyzewicz ◽

Mirjam Renovanz ◽

...

Keyword(s):

Minimally Invasive ◽

Image Guidance ◽

Spinal Instrumentation ◽

Pedicle Screws ◽

Screw Placement ◽

Complication Rates ◽

Intraoperative Radiation ◽

Invasive Approach ◽

Placement Accuracy ◽

Spinal Image

ObjectiveRecent studies have investigated the role of spinal image guidance for pedicle screw placement. Many authors have observed an elevated placement accuracy and overall improvement of outcome measures. This study assessed a bi-institutional experience following introduction of the Renaissance miniature robot for spinal image guidance in Europe.MethodsThe medical records and radiographs of all patients who underwent robot-guided implantation of spinal instrumentation using the novel system (between October 2011 and March 2015 in Mainz and February 2014 and February 2016 in Regensburg) were reviewed to determine the efficacy and safety of the newly introduced robotic system. Screw position accuracy, complications, exposure durations to intraoperative radiation, and reoperation rate were assessed.ResultsOf the 413 surgeries that used robotic guidance, 406 were via a minimally invasive approach. In 7 cases the surgeon switched to conventional screw placement, using a midline approach, due to referencing problems. A total of 2067 screws were implanted using robotic guidance, and 1857 screws were evaluated by postoperative CT. Of the 1857 screws, 1799 (96.9%) were classified as having an acceptable or good position, whereas 38 screws (2%) showed deviations of 3–6 mm and 20 screws (1.1%) had deviations > 6 mm. Nine misplaced screws, implanted in 7 patients, required revision surgery, yielding a screw revision rate of 0.48% of the screws and 7 of 406 (1.7%) of the patients. The mean ± SD per-patient intraoperative fluoroscopy exposure was 114.4 (± 72.5) seconds for 5.1 screws on average and any further procedure required. Perioperative and direct postoperative complications included hemorrhage (2 patients, 0.49%) and wound infections necessitating surgical revision (20 patients, 4.9%).ConclusionsThe hexapod miniature robotic device proved to be a safe and robust instrument in all situations, including those in which patients were treated on an emergency basis. Placement accuracy was high; peri- and early postoperative complication rates were found to be lower than rates published in other series of percutaneous screw placement techniques. Intraoperative radiation exposure was found to be comparable to published values for other minimally invasive and conventional approaches.

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Rate of instrumentation changes on postoperative and follow-up radiographs after primary complex spinal fusion (five or more levels) for adult deformity correction

Journal of Neurosurgery Spine ◽

10.3171/2018.9.spine18686 ◽

2019 ◽

Vol 30 (3) ◽

pp. 376-381

Author(s):

Aladine A. Elsamadicy ◽

David T. Lubkin ◽

Amanda R. Sergesketter ◽

Syed M. Adil ◽

Lefko T. Charalambous ◽

...

Keyword(s):

Spinal Fusion ◽

Spine Surgery ◽

Deformity Correction ◽

The United States ◽

Spine Deformity ◽

Complication Rates ◽

Old Patients ◽

Primary Complex ◽

The Mean

OBJECTIVEIn the United States, healthcare expenditures have been soaring at a concerning rate. There has been an excessive use of postoperative radiographs after spine surgery and this has been a target for hospitals to reduce unnecessary costs. However, there are only limited data identifying the rate of instrumentation changes on radiographs after complex spine surgery involving ≥ 5-level fusions.METHODSThe medical records of 136 adult (≥ 18 years old) patients with spine deformity undergoing elective, primary complex spinal fusion (≥ 5 levels) for deformity correction at a major academic institution between 2010 and 2015 were reviewed. Patient demographics, comorbidities, and intra- and postoperative complication rates were collected for each patient. The authors reviewed the first 5 subsequent postoperative and follow-up radiographs, and determined whether revision of surgery was performed within 5 years postoperatively. The primary outcome investigated in this study was the rate of hardware changes on follow-up radiographs.RESULTSThe majority of patients were female, with a mean age of 53.8 ± 20.0 years and a body mass index of 27.3 ± 6.2 kg/m2 (parametric data are expressed as the mean ± SD). The median number of fusion levels was 9 (interquartile range 7–13), with a mean length of surgery of 327.8 ± 124.7 minutes and an estimated blood loss of 1312.1 ± 1269.2 ml. The mean length of hospital stay was 6.6 ± 3.9 days, with a 30-day readmission rate of 14.0%. Postoperative and follow-up change in stability on radiographs (days from operation) included: image 1 (4.6 ± 9.3 days) 0.0%; image 2 (51.7 ± 49.9 days) 3.0%; image 3 (142.1 ± 179.8 days) 5.6%; image 4 (277.3 ± 272.5 days) 11.3%; and image 5 (463.1 ± 525.9 days) 15.7%. The 3rd year after surgery had the highest rate of hardware revision (5.55%), followed by the 2nd year (4.68%), and the 1st year (4.54%).CONCLUSIONSThis study suggests that the rate of instrumentation changes on radiographs increases over time, with no changes occurring at the first postoperative image. In an era of cost-conscious healthcare, fewer orders for early radiographs after complex spinal fusions (≥ 5 levels) may not impact patient care and can reduce the overall use of healthcare resources.

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Tissue Expansion for Severe Foot and Ankle Deformities: A 16-Year Review

Plastic Surgery ◽

10.1177/2292550317749510 ◽

2018 ◽

Vol 26 (4) ◽

pp. 244-249

Author(s):

Kevin J. Nickel ◽

Aaron C. Van Slyke ◽

Aaron D. Knox ◽

Kevin Wing ◽

Neil Wells

Keyword(s):

Lower Extremity ◽

Pediatric Population ◽

Case Series ◽

Deformity Correction ◽

Tissue Expansion ◽

Retrospective Chart Review ◽

Complication Rates ◽

Foot And Ankle ◽

Major Complications ◽

To Receive

Background: Tissue expansion in the lower extremity is controversial, with studies reporting complication rates as high as 83%. Few studies have looked at tissue expansion prior to orthopaedic correction of severe foot and ankle deformities, and those available are restricted to clubfoot in the pediatric population. Here, we report the largest case series on the use of tissue expanders for the reconstruction of severe foot and ankle deformity and the only report in adults. Methods: This is a retrospective chart review of the senior author’s practice over a 16-year study period. All patients over 18 years of age who underwent tissue expansion prior to definitive orthopaedic correction of a severe foot and ankle deformity were included. Patient demographics, etiology of deformity, rate of expansion, and complications were recorded. Major complications were defined as those which required surgical intervention. Data were analyzed using descriptive statistics. Results: Nineteen cases were performed on 16 patients. Our overall complication rate was 31.6% (6/19), with major complications occurring in 21.1% (4/19) of cases, and minor complications occurring in 10.5% (2/19) of cases. Despite this, 94.7% (18/19) of cases went on to receive definitive orthopaedic correction after tissue expansion. No demographic parameters were associated with occurrence of complications. Conclusions: This represents the largest report on lower extremity tissue expansion for severe foot and ankle deformity correction. While we observed complications in 31.6% of patients, 94.7% of cases went on to receive definitive orthopaedic correction with successful primary closure.

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Navigated iliac screw placement may reduce radiation and OR time in lumbopelvic fixation of unstable complex sacral fractures

European Journal of Orthopaedic Surgery & Traumatology ◽

10.1007/s00590-021-02892-7 ◽

2021 ◽

Author(s):

M. F. Hoffmann ◽

E. Yilmaz ◽

D. C. Norvel ◽

T. A. Schildhauer

Keyword(s):

Radiation Exposure ◽

Operative Time ◽

Pelvic Ring ◽

Screw Placement ◽

Fluoroscopy Time ◽

Complication Rates ◽

Lumbopelvic Fixation ◽

Navigation Group ◽

Iliac Screws ◽

Iliac Screw

Abstract Purpose Instability of the posterior pelvic ring may be stabilized by lumbopelvic fixation. The optimal osseous corridor for iliac screw placement from the posterior superior iliac spine to the anterior inferior iliac spine requires multiple ap- and lateral-views with additional obturator-outlet and -inlet views. The purpose of this study was to determine if navigated iliac screw placement for lumbopelvic fixation influences surgical time, fluoroscopy time, radiation exposure, and complication rates. Methods Bilateral lumbopelvic fixation was performed in 63 patients. Implants were inserted as previously described by Schildhauer. A passive optoelectronic navigation system with surface matching on L4 was utilized for navigated iliac screw placement. To compare groups, demographics were assessed. Operative time, fluoroscopic time, and radiation were delineated. Results Conventional fluoroscopic imaging for lumbopelvic fixation was performed in 32 patients and 31 patients underwent the procedure with navigated iliac screw placement. No differences were found between the groups regarding demographics, comorbidities, or additional surgical procedures. Utilization of navigation led to fluoroscopy time reduction of more than 50% (3.2 vs. 8.6 min.; p < 0.001) resulting in reduced radiation (2004.5 vs. 5130.8 Gy*cm2; p < 0.001). Operative time was reduced in the navigation group (176.7 vs. 227.4 min; p = 0.002) despite the necessity of additional surface referencing. Conclusion For iliac screws, identifying the correct entry point and angle of implantation requires detailed anatomic knowledge and multiple radiographic views. In our study, additional navigation reduced operative time and fluoroscopy time resulting in a significant reduction of radiation exposure for patients and OR personnel.

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