Postoperative Computed Tomography Scans Research Articles

Pedicle Screw-Associated Violation of the Adjacent Unfused Facet Joint: Clinical Outcomes and Fusion Rates.

Retrospective review of a prospective randomized trial. To compare outcome scores and fusion rates in patients with and without pedicle screw-associated facet joint violation (FJV) after a single-level lumbar fusion. Clinical outcomes data and computed tomography (CT) imaging were reviewed for 157 patients participating in a multicenter prospective trial. Post-operative CT scans at 12-months follow-up were examined for fusion status and FJV. Patient-reported outcomes (PROs) included Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) for leg and low back pain. Chi-square test of independence was used to compare proportions between groups on categorical measures. Two-sample t-test was used to identify differences in mean patient outcome scores. Logistic regression models were performed to determine association between FJV and fusion rates. Of the 157 patients included, there were 18 (11.5%) with FJV (Group A) and 139 (88.5%) without FJV (Group B). Patients with FJV experienced less improvement in ODI (P = .004) and VAS back pain scores (P = .04) vs patients without FJV. There was no difference in mean VAS leg pain (P = .4997). The rate of fusion at 12-months for patients with FJV (27.8%) was lower compared to those without FJV (71.2%) (P = .0002). Patients with FJV were 76% less likely to have a successful fusion at 12-months. Pedicle screw-associated violation of the adjacent unfused facet joint during single-level lumbar fusion is associated with less improvement in back pain, back pain-associated disability, and a lower fusion rate at 1-year after surgery.

Lateral Thoracic Expansion for Jeune's Syndrome, Surgical Approach, and Technical Details

Jeune's syndrome, or asphyxiating thoracic dystrophy (ATD), is a rare autosomal recessive disorder characterized by skeletal dysplasia. Ribs are typically short and horizontal resulting-in lethal variant-in severe lung hypoplasia, progressive respiratory failure, and death. Lateral thoracic expansion (LTE) consists in staggered bilateral ribs osteotomy leading to chest expansion and lung development. Studies on LTE in ATD patients report encouraging data, but the rarity of ATD implies the lack of a standardized surgical path. The aim of this report is to present our experience with LTE, the technical modification we adopted, and patients' clinical outcome. We retrospectively reviewed data of 11 LTE performed in 7 ATD patients with lethal variant. Information regarding pre- and postoperative clinical conditions and surgical details was collected. We adopted a single-stage or a two-stage approach based on patient clinical condition. Computed tomography (CT) scan was performed before and after surgery and lung volume was calculated. Five patients are alive, while two died in intensive care unit for other than respiratory cause (sepsis). Most patients experienced clinical improvement in terms of decreased respiratory infections rate, need for ventilation, and improved exercise tolerance. Postoperative CT scan demonstrated a median lung volume increase of 88%. Mortality in ADT patients is high. However, LTE is a feasible and safe surgical approach, which could improve clinical conditions and survival rate. Survived patients showed postoperatively less oxygen requirement and improved clinical conditions.

Severe Tortuosity of the Distal Descending Thoracic Aorta Affects the Accuracy of Distal Deployment During a Thoracic Endovascular Aortic Repair

Purpose: An accurate distal deployment is essential for successful thoracic endovascular aortic repair (TEVAR) of a paradiaphragmatic aortic aneurysm. This study aimed to investigate the anatomical and intraoperative factors that affect the accuracy of distal deployment during TEVAR. Methods: We conducted a retrospective review of preoperative and postoperative computed tomography scans of 426 patients undergoing TEVAR at our institution between October 2008 and May 2021, of which the stent-graft was attempted to be deployed just above the celiac axis or the superior mesenteric artery in 56 patients. Based on the anatomical factors related to the malposition (deployed >10 mm away from the target vessel) and the greater curve to the straight-line ratio (G/S ratio), the patients were categorized as severe tortuosity (n=21) and mild tortuosity (n=35) groups to compare the operative and clinical outcomes. Result: Stent-graft malpositioning occurred in 21 cases. Among all anatomical variables, only the G/S ratio was significantly larger in the malpositioned cases (p=0.049). A cutoff G/S ratio value of 1.15 was determined using the receiver operating curve analysis. In the severe tortuosity group, the distal end of the stent-graft was significantly farther (median: 10.0 [interquartile range (IQR): 2.5–19.5] mm vs 3.0 [0–8.0] mm; p=0.015) from the target vessel, and the tilt angle of the stent-graft’s distal edge was larger (median: 21.4 [IQR: 15.8–24.5] vs 9.5 [5.5–12.5] degree; p<0.01) than that in the mild tortuosity group. Both groups were comparable for the incidence of a primary type Ib endoleak (p=0.454), a secondary type Ib endoleak (p=1.0), and the rate of distal reintervention (p=0.276). Conclusion: Severe tortuosity in the distal descending thoracic aorta is associated with a malpositioned and tilted distal end of the stent-graft. Clinical Impact Thoracic endovascular aortic repair (TEVAR) for paradiaphragmatic thoracic aortic aneurysms requires accurate distal landing. In this paper, a retrospective CT analysis revealed that the greater curve to the straight-line ratio (G/S ratio) was associated to affects the malposition of the stent graft, defined as being deployed more than 10 mm away from the target vessel. Further, a comparative analysis based on the G/S ratio demonstrated that severe aortic tortuosity was associated with a more distal and tilted deployment of the stent graft.

A Retrospective Analysis of Pedicle Screw Placement Accuracy Using the ExcelsiusGPS Robotic Guidance System: Case Series.

Robotic guidance has become widespread in spine surgery. Although the intent is improved screw placement, further system-specific data are required to substantiate this intention for pedicle screws in spinal stabilization constructs. To determine the accuracy of pedicle screws placed with the aid of a robot in a cohort of patients immediately after the adoption of the robot-assisted surgery technique. A retrospective, Institutional Review Board-approved study was performed on the first 100 patients at a single facility, who had undergone spinal surgeries with the use of robotic techniques. Pedicle screw accuracy was graded using the Gertzbein-Robbins Scale based on pedicle wall breach, with grade A representing 0 mm breach and successive grades increasing breach thresholds by 2 mm increments. Preoperative and postoperative computed tomography scans were also used to assess offsets between the objective plan and true screw placements. A total of 326 screws were analyzed among 72 patients with sufficient imaging data. Ages ranged from 21 to 84 years. The total accuracy rate based on the Gertzbein-Robbins Scale was 97.5%, and the rate for each grade is as follows: A, 82%; B, 15.5%; C, 1.5%; D, 1%; and E, 0. The average tip offset was 1.9 mm, the average tail offset was 2.0 mm, and the average angular offset was 2.6°. Robotic-assisted surgery allowed for accurate implantation of pedicle screws on immediate adoption of this technique. There were no complications attributable to the robotic technique, and no hardware revisions were required.

Computer-aided design and manufacturing technology applied to total nasal reconstruction

The principles of nasal reconstruction include the need to reconstruct three tissue layers, the need to restore entire skin aesthetical units, and, possibly, the replacement with like tissues. Computer-aided design (CAD) and computer-aided manufacturing (CAM) technologies were applied to two total nasal reconstructions in male patients who underwent rhinectomy for cancer. Three-dimensional (3D) data were obtained from computerized tomography (CT) scan-derived DICOM files (Digital Imaging and Communications in Medicine), this allowed us to design the shape of the reconstructive nose in order to mimic the native nose and to plan dimensions and angles. A custom-made titanium plate was manufactured for the structure and a bi-dimensional template for the forehead flap was printed. The patients underwent a total nasal reconstruction in three layers: local flaps for the lining, custom-made titanium plate for the structure, and expanded forehead flap for the skin. Forehead flap pedicle was divided 3 weeks postoperatively under local anesthesia in an outpatient clinic, as well as further minor refinements. The patients underwent a 6-month post-operative CT scan in order to compare the result to the planned nose. No complications were reported. The superimposition demonstrated a 92% match in case 1 and 95% match in case 2 between the reconstructed nose and the planned one. Forehead flap is still the most favorable option for nasal reconstruction, CAD technology allows to implement the planning and makes the procedure easier; moreover, the use of a CAM plate for the structure allows to reconstruct a nose with the desired naso-frontal angle.Level of evidence: level V, therapeutic study.

Improvements in airflow characteristics and effect on the NOSE score after septoturbinoplasty: A computational fluid dynamics analysis.

Septoturbinoplasty is a surgical procedure that can improve nasal congestion symptoms in patients with nasal septal deviation and inferior turbinate hypertrophy. However, it is unclear which physical domains of nasal airflow after septoturbinoplasty are related to symptomatic improvement. This work employs computational fluid dynamics modeling to identify the physical variables and domains associated with symptomatic improvement. Sixteen numerical models were generated using eight patients' pre- and postoperative computed tomography scans. Changes in unilateral nasal resistance, surface heat flux, relative humidity, and air temperature and their correlations with improvement in the Nasal Obstruction Symptom Evaluation (NOSE) score were analyzed. The NOSE score significantly improved after septoturbinoplasty, from 14.4 ± 3.6 to 4.0 ± 4.2 (p < 0.001). The surgery not only increased the airflow partition on the more obstructed side (MOS) from 31.6 ± 9.6 to 41.9 ± 4.7% (p = 0.043), but also reduced the unilateral nasal resistance in the MOS from 0.200 ± 0.095 to 0.066 ± 0.055 Pa/(mL·s) (p = 0.004). Improvement in the NOSE score correlated significantly with the reduction in unilateral nasal resistance in the preoperative MOS (r = 0.81). Also, improvement in the NOSE score correlated better with the increase in surface heat flux in the preoperative MOS region from the nasal valve to the choanae (r = 0.87) than in the vestibule area (r = 0.63). Therefore, unilateral nasal resistance and mucous cooling in the preoperative MOS can explain the perceived improvement in symptoms after septoturbinoplasty. Moreover, the physical domain between the nasal valve and the choanae might be more relevant to patient-reported patency than the vestibule area.

Predictive Factors for Lateral Hinge Fracture in Medial Closing Wedge Distal Femoral Osteotomy

Background: Recent studies have reported that lateral hinge fracture (LHF) has a negative effect on bone healing at the osteotomy site after medial closing wedge distal femoral osteotomy (MCDFO). However, limited evidence exists in the literature regarding the predictive factors for LHF in MCDFO. Hypothesis: A large medial closing gap and a lateral hinge position in the supracondylar area would increase plain radiography–based and/or computed tomography (CT)–based LHF in MCDFO. Study Design: Case control study; Level of evidence, 3. Methods: We retrospectively evaluated 67 knees of 53 patients (mean age, 37.4 ± 16.9 years) who underwent MCDFO between May 2009 and June 2021. The surgical indications for MCDFO were genu valgum deformity combined with either lateral compartment osteoarthritis or recurrent patellar dislocation. The presence of LHF was evaluated based on immediate postoperative plain radiography and CT scans. The predictive factors for LHF in MCDFO were investigated using multivariate logistic regression analysis. Results: LHFs were identified in 21 knees (31.3%) through plain radiography and in 40 knees (59.7%) through CT. Multivariate logistic regression analysis showed that the medial closing gap and lateral hinge position were predictive factors for plain radiography– and CT-based LHF after MCDFO. Controlling for other variables, we found that an increase in the medial opening gap by 1 mm increased the likelihood of plain radiography–based LHF by a factor of 1.805 (95% CI, 1.291-2.525; P = .001) and CT-based LHF by 1.333 (95% CI, 1.003-1.772; P = .048). Moreover, a lateral hinge position in the supracondylar area increased the likelihood of plain radiography–based LHF by a factor of 9.870 (95% CI, 2.179-44.720; P = .003) and CT-based LHF by 5.686 (95% CI, 1.124-28.754; P = .036). Conclusion: A large medial closing gap and lateral hinge position in the supracondylar area are associated with LHF in MCDFO. Care should be taken to prevent LHF in MCDFO with a large medial closing gap. Moreover, a lateral hinge position in the supracondylar area should be avoided to decrease the incidence of LHF in MCDFO.

Early Postoperative CT Scan Provides Prognostic Data on Clinical Outcomes of Fresh Osteochondral Transplantation of the Knee

Background: There is a lack of information regarding the ability of imaging studies to predict clinical outcomes after fresh osteochondral allograft (FOCA) transplantation of the knee. Purpose: To determine the value of computed tomography (CT) scans to predict the clinical outcome of FOCA transplantation using the assessment computed tomography osteochondral allograft (ACTOCA) score. Study Design: Cohort study; Level of evidence, 3. Methods: We prospectively collected data from all consecutive patients who underwent FOCA transplantation for osteochondral knee lesions at one institution between August 2017 and August 2019. All patients were followed up for a minimum of 2 years. CT scans performed 6 months after surgery were evaluated by a musculoskeletal radiologist using the ACTOCA scoring system. The radiologist was blinded to the patient’s medical history. Clinical outcomes were assessed preoperatively and at 12 and 30 months postoperatively using the International Knee Documentation Committee (IKDC) score, the Kujala score, the Tegner activity scale, and the Western Ontario Meniscal Evaluation Tool (WOMET) score. Results: A total of 38 cases were included. The ACTOCA score at 6 months after surgery showed a statistically significant correlation with clinical results at 12 and 30 months. The correlation was better at 30 months, showing a high negative correlation with the IKDC score (−0.663) and a moderate negative correlation with the Kujala, WOMET, and Tegner scores (−0.593; −0.547, and −0.593, respectively) (P < .001). Conclusion: A statistically significant correlation between the mean ACTOCA score on CT scans at 6 months and the clinical results measured by the IKDC, Kujala, WOMET, and Tegner scores at 30 months confirmed the predictive value of the ACTOCA score for use in clinical practice.

Relevance of posterior malleolar fracture fixation to ankle syndesmotic reduction, a comparative study

&lt;p&gt;&lt;strong&gt;Background:&lt;/strong&gt;&lt;strong&gt; &lt;/strong&gt;Appropriate distal tibiofibular syndesmotic reduction is crucial to restore ankle stability, guard against future arthrosis with worse functional outcome. Optimal technique for syndesmotic reduction has been a matter of debate. This study aimed at radiological evaluation of syndesmotic integrity following two methods of reduction (posterior malleolar fixation and trans-syndesmotic screw fixation), additionally, correlating the posterior malleolus size to the radiological results of both techniques.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;Syndesmotic integrity was compared after each technique as per translational and rotational fibular positions. Utilizing, preoperative and postoperative computed tomography scans of injured ankle, the fibular antero-posterior and Medio-lateral translation distances were measured. Additionally, the fibular rotation angle was calibrated. Incidence of inadequate reduction in each group was reported. Preoperative and postoperative radiological findings were compared and correlated to posterior malleolus size in relation to tibial articular distance.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results:&lt;/strong&gt; A significant difference between both techniques was noted in term of fibular rotation. In patients with PM ˂ 10% of tibial articular surface, a significant difference was obvious in postoperative AP-translational and rotational findings between both techniques. Overall malreduction incidence rate of 68.9% was reported in this study, with 84.7% rate in patients managed with SS-fixation, whilst 51.2% rate in those managed via PM-fixation.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt;&lt;strong&gt; &lt;/strong&gt;Posterior malleolar fixation could limit syndesmotic malreduction risk whatsoever it’s size. Approaching CT reference values for syndesmotic reduction might benefit preoperative planning and detect intraoperative malreduction. Further future clinical studies correlating these findings to clinical outcome would be more helpful.&lt;/p&gt;

Clinical Importance of Hounsfield Unit in Computed Tomography of Sub-Axial Cervical Vertebral Body.

Objective: Computed tomography (CT) is an often-used diagnostic imaging tool during the evaluation of the cervical spine pathology. CT scan can provide one’s bone density by measuring Hounsfield’s unit. In anterior cervical discectomy and fusion (ACDF) surgeries, bone density may play an important role as it may relate to non-union. Therefore, the evaluation and consideration of the Hounsfield’s unit of sub-axial cervical vertebral body is important, especially during multi-level ACDF.Methods: Patients who have taken cervical CT scan pre-operatively to multi-level (3 or 4 levels) anterior cervical discectomy and fusion with anterior plating between June 2010 and August 2018, at our department were retrospectively reviewed. The bone density was estimated by measuring Hounsfield Unit (HU) of sub-axial vertebrae - C3 to T1 - by using PiViewStar imaging software program. Radiological evaluation of fusion was done by assessing postoperative plain X-rays and CT scans of 4 months and 1-year follow-up. The difference in HU were evaluated between different segments of sub-axial vertebrae. Then the fusion rate of the ACDF ending at C6 were compared to C7. All grouped values were tested for normality using the Shapiro-Wilk test. Matched-ANOVA and Fisher’s exact test was used.Results: A total of eighty patients were who underwent 3 or 4 level ACDF with anterior plate fixation were retrospectively reviewed. Bone density estimated from Hounsfield unit (HU) measurement of the sub-axial vertebral bodies ranges from 112.2 to 594.9 with the mean of 280.91. When comparing C5 with 6, 6 with 7, and 7 with T1 they showed significantly decreasing HU value with p-value&lt;0.01 with mean difference of 49.10, 30.98, and 31.25, respectively. ACDF ending at C7 showed significantly lower fusion rate than C6 at 4 months and 1-year follow-up, respectively.Conclusion: The HU show a decreasing trend towards lower sub-axial cervical vertebral body. Furthermore, multi-level ACDF ending at C7 showed higher non-union rate than ending at C6. Although, there is no direct evidence that lower bone density at lower sub-axial cervical vertebrae is causative for non-union, it should be considered for pre-operative planning.

Physician-Modified Stent Graft for Blunt Thoracic Aortic Injuries: Do the Benefits Worth the Trouble?

Obtaining a suitable proximal landing zone in blunt thoracic aortic injuries (BTAI) often necessitates coverage of the left subclavian artery (LSA). This study aimed to evaluate the outcomes of physician-modified endovascular grafts (PMEGs) in this indication. We performed a retrospective analysis of a prospective registry including all patients who had undergone a thoracic endovascular aortic repair (TEVAR) for BTAI from October 2008 to October 2020. Starting in 2015, patients requiring coverage of the LSA were either treated using a physician-modified proximal scalloped or single-fenestrated stent graft. After an early postoperative computed tomography scan, follow-up was performed at 3 months, 6-months, and yearly. Among 58 patients treated with TEVAR for BTAI, 23 (39.6%) patients required a zone 2 landing zone of which 10 (17.2%) patients were treated with PMEGs. The median age was 48 [31-64.5] years, and 78.2% (n=18) patients were male. The median Injury Severity Score was 38 [27-55.5]. Coverage of the LSA was performed in 25.8% (n=15) of the total population in which 5 patients had an LSA transposition. The median modification time was 18 [14-27] minutes. Technical success of PMEGs was 90.0% overall and 100% for fenestrated stent grafts. No stroke, paraplegia, or retrograde dissection was observed. The primary patency of the LSA in the PMEGs group was 90 % at 1year and 28.8 % in the LSA coverage group (P<0.01). The use of PMEGs is feasible and effective in the management of BTAI with a short proximal landing zone. Further evaluation of long-term outcomes and durability are awaited.

A standardized method of measuring screw breach on postoperative computed tomography scans following percutaneous fixation of the posterior pelvic ring.

To assess the reliability of a standardized measurement of screw breach on postoperative computed tomography (CT) scans following percutaneous fixation of the posterior pelvic ring. Three orthopedic trauma surgeons independently utilized a standardized method of measuring posterior pelvic ring screw breaches on post-operative CT scan images. Breaches were measured as a continuous variable on sagittal images reformatted to be perpendicular to the screw on axial images. The inter-rater and intra-rater reliability of screw breach distance measurements was assessed. Measurements were performed on 42 screws in 20 patients. Screw types included S1-iliosacral (IS) (n = 16), S1-transsacral (TS) (n = 8), S2-IS (n = 2), and S2-TS (n = 16). Patients with varying degrees ofscrew breacheswere chosen to test measurements across breach severities, including0mm (n = 10), ≤ 2mm (n = 12), > 2 to 4mm (n = 11), and > 4mm (n = 9). The mean difference and 95% confidence interval (CI) between screw breach measurements between the three surgeons was - 0.13mm (CI - 0.48 to 0.20), 0.05mm (CI - 0.6 to 0.7), and 0.18mm (CI - 0.47 to 0.85), respectively. The inter-rater reliability of the measurements was considered excellent (intraclass correlation coefficient (ICC), 0.93). The mean intra-rater reliability for the observers was considered good (ICC 88.5, CI 82 to 95). This simple standardized method of measuring screw breaches had excellent inter-rater reliability and would support comparisons of screw breach severity across studies. Level III.

Defining Sacral Dysmorphism: What Size Corridor Precludes Transsacral Screw Placement.

To determine what size S1-transsacral (TS) corridor is amenable to TS screw placement, as this is commonly used to identify sacral dysmorphism, and to determine if gender, ethnicity, or screw breach is associated with narrow corridors. Retrospective review. Urban level-1 trauma center. Two hundred ninety patients with pelvic ring injuries and preoperative computed tomography (CT) scans. Percutaneous posterior pelvic ring fixation. The width of the S1-TS corridor was measured on the axial (inlet) and coronal (outlet) reformatted CT images. Patients with S1-TS screw fixation and postoperative CT scans were identified. Corridor size, gender, ethnicity, and screw breach were documented. S1-TS screws were placed in 55 of the 290 patients. No S1-TS screws were placed in corridors less than 8 mm. Corridors of &lt;8 mm were present in 114 (39%) of the 290 patients and were not associated with gender or ethnicity. S1-TS screws placed in small (&lt;10 mm) versus large (≥10 mm) corridors did not have a detectable difference in screw breaches (5 of 8, 62% versus 19 of 47 40%; difference, 22%, 95% confidence interval -14% to 52%) or median (interquartile range) screw breach distance [3 mm (2.5-4.8) versus 3 mm (1.2-4.8); difference, 0.9 mm; confidence interval -1.6 to 2.2]. These data are useful for the standardization of sacral dysmorphism reporting based on corridor size. Screw breaches were common irrespective of TS corridor size, emphasizing the small degree of error allowed by this procedure. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Percutaneous iliosacral screw insertion with only outlet and inlet fluoroscopic view for unstable pelvic ring injuries: Clinical and radiological outcomes.

Percutaneous iliosacral screw fixation in posterior pelvic ring fractures is challenging and commonly performed under fluoroscopy or navigation techniques. This study aimed to assess the safety and efficacy of percutaneous iliosacral screw implantation under fluoroscopy guidance with only inlet and outlet views. This retrospective study included 58 consecutive unstable posterior pelvic injury patients (36 sacral fractures and 22 sacroiliac joint disruptions) treated with percutaneous iliosacral screws between January 2015 and November 2019. Acceptable inlet radiographs show the anterior cortex of the S1 body superimposed on the S2 body. Acceptable outlet radiographs show the superior pubic symphysis at the level of the S2 foramen and visualize the S1 and S2 sacral foramina. In our technique, the screw was inserted at the inferior half of the outlet view and the posterior half of the inlet view. The time needed for screw insertion and the radiation exposure time was recorded. Intra and postoperative complications were documented. Postoperative computed tomography (CT) scans assessed screw position. In total, 69 iliosacral screws were inserted in 58 patients. In postoperative CT scans, the screw position was assessed, 89.8% were in a secure position, and 10.2% had malposition. The mean operation time per screw was 21.18 min and the mean fluoroscopy time per screw was 112 s. There was no evidence of wound infection or iatrogenic neurovascular injury. No reoperation was performed. Percutaneous iliosacral screws can be placed using the only outlet and inlet fluoroscopic views with comparable radiological and clinical outcomes to the conventional method.

Safety and Accuracy of Freehand Pedicle Screw Placement and the Role of Intraoperative O-Arm: A Single-Institution Experience.

Retrospective cohort study. The aim was to investigate the accuracy of pedicle screw placement by freehand technique and to compare revision surgery rates among three different imaging verification pathways. Studies comparing different imaging modalities in freehand screw placement surgery are limited. A single-institution retrospective chart review identified adult patients who underwent freehand pedicle screw placement in the thoracic, lumbar or sacral levels. Patients were stratified into three cohorts based on the intraoperative imaging modality used to assess the accuracy of screw position: intraoperative X-rays (cohort 1); intraoperative O-arm (cohort 2); or intraoperative computed tomography (CT)-scan (cohort 3). Postoperative CT scans were performed on all patients in cohorts 1 and 2. Postoperative CT scan was not required in cohort 3. Screw accuracy was assessed using the Gertzbein-Robbins grading system. A total of 9179 pedicle screws were placed in the thoracic or lumbosacral spine in 1311 patients. 210 (2.3%) screws were identified as Gertzbein-Robbins grades C-E on intraoperative/postoperative CT scan, 137 thoracic screws, and 73 lumbar screws ( P <0.001). Four hundred and nine patients underwent placement of 2754 screws followed by intraoperative X-ray (cohort 1); 793 patients underwent placement of 5587 screws followed by intraoperative O-arm (cohort 2); and 109 patients underwent placement of 838 screws followed by intraoperative CT scan (cohort 3). Postoperative CT scans identified 65 (2.4%) and 127 (2.3%) malpositioned screws in cohorts 1 and 2, respectively. Eleven screws (0.12%) were significantly malpositioned and required a second operation for screw revision. Nine patients (0.69%) required revision operations: eight of these patients were from cohort 1 and one patient was from cohort 2. When compared to intraoperative X-ray, intraoperative O-arm verification decreased the revision surgery rate for malpositioned screws from 0.37% to 0.02%. In addition, our analysis suggests that the use of intraoperative O-arm can obviate the need for postoperative CT scans.

Novel Covert-Inferior Pelvic Approach with a Subpubic Plate for Anterior Pelvic Ring Fractures: Preliminary Results.

Anterior pelvic ring injuries can be treated via Pfannenstiel, modified Stoppa, or ilioinguinal approaches, but these require exposing the abdominal soft tissues and may damage pelvic organs. The scar on the abdominal wall is also unacceptable for some patients. The minimally invasive anterior pelvic ring internal fixator (INFIX) is not ideal for thin patients with easily irritated skin, and it is associated with complications such as femoral nerve palsy, vascular occlusion, and lateral femoral cutaneous nerve injury. In this study, we designed a new external pelvic approach for the treatment of an anterior pelvic ring fracture. We retrospectively reviewed 28 patients with 36 pubic ramus fractures that had been treated via the covert-inferior pelvic approach. All patients underwent a surgical procedure between August 2019 and January 2021. According to the Nakatani classification, there were 6 cases of type-I fracture, 25 cases of type-II fracture, and 5 cases of type-III fracture. Operative time, blood loss, and postoperative radiographic and computed tomographic (CT) findings were recorded. Patients were followed for fracture healing time, functional status, esthetic satisfaction, and complications. A total of 27 patients had follow-up for at least 12 months (range, 12 to 29 months). Postoperative radiographs and CT scans showed well-positioned plates and screws. The mean preoperative time was 9.4 ± 3.8 days, the mean operative time was 61.3 ± 22.67 minutes, the mean intraoperative blood loss was 63.6 ± 42.62 mL, the mean fracture healing time was 4.1 ± 1.6 months, and the mean Majeed score was 89.74 ± 8.07. There were no complications of nonunion, internal fixation failure, vascular injury, nerve palsy, or hernia. All of the patients were esthetically satisfied with the scar. The covert-inferior pelvic approach combined with a subpubic plate effectively fixed Nakatani type-I, II, and III fractures. The advantages of this method include rapid recovery after the surgical procedure, safety, simplicity, a short learning curve, no damage to abdominal soft tissue, no effect on pubic symphysis micromotion, and esthetic benefits. It may be another option for anterior pelvic ring fractures and can supplement other approaches. Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

A Novel Bone Contouring Technique Using Multiple Tangential Shaving for Conservative Management of Craniofacial Fibrous Dysplasia.

This study aimed to propose a novel surgical technique, named multiple tangential shaving of bone contour, for the conservative management of craniofacial fibrous dysplasia. We retrospectively reviewed 17 patients who underwent conservative management of craniofacial fibrous dysplasia using multiple tangential shaving technique between July 2005 and December 2020. Demographics, tumor characteristics, and surgery-related factors were investigated. All patients underwent preoperative (T0) and postoperative computed tomography scans taken at least twice within 1 month for immediate assessment (T1) and at least 12 months postoperatively for long-term assessment (T2). Clinical outcomes, including tumor recurrence, perioperative complications, and physician measure of esthetic outcomes (Whitaker score), were investigated. This technique was applied for contouring of the zygomatic-maxillary and calvarial bone for patients aged between 16 and 60 years (mean age: 26y). The mean±SD tumor volume reduction was 15.5±8.95cm 3 , and the postoperative mean±SD tumor growth rate was 5.52±6.26% per year. Satisfactory outcome was obtained in terms of esthetics with a mean±SD Whitaker score of 1.41±0.62. Patients required a mean operation time of 1.67±0.43 hours and a mean number of shaving operations of 1.35±0.61 during the follow-up period. Five of 17 patients required reoperation because of the tumor recurrence (N=4) and to correct new-onset diplopia after surgery (N=1). In conclusion, the multiple tangential shaving technique allows an easy approach for conservative management of craniofacial fibrous dysplasia. An acceptable rate of tumor recurrence and esthetic outcomes can be obtained by selecting the appropriate candidate for a conservative approach.

Novel Multiportal Approach to the Internal Auditory Canal for Hearing-Preserving Surgery: Feasibility Assessment in Dissections

State-of-the-art, minimally invasive endoscopic transcanal surgery of the internal auditory canal (IAC) sacrifices the cochlea with complete hearing loss. With a combination of the transcanal infracochlear and transmastoid retrolabyrinthine approaches, we aim to preserve hearing and enable minimally invasive surgical treatment of vestibular schwannoma. In this study, we investigate the anatomical indications and the feasibility of both approaches in dissections, in human whole head specimens. We operated whole head anatomical specimens with a four-handed technique, using the retrolabyrinthine approach as the main surgical corridor and the infracochlear approach for endoscopic visualization. We tested 4 different powered surgical systems. We collected intraoperative data on the size of the access windows, the surgical freedom, and the exposed area of the IAC. Finally, we evaluated the outcome in postoperative computed tomography scans. Six out of 14 sides were anatomically suitable and qualified for the surgery based on preoperative computed tomography. In all attempted sides, the IAC could be reached and opened, leaving the ossicular chain and the labyrinth intact. 51%-75% of the length and 22%-40% of the circumference of the IAC could be exposed. All tested instruments were beneficial at different stages of the surgery. The four-handed technique enabled good maneuverability of the instruments. The combined multiportal approach to the IAC is feasible with a good surgical exposure and full anatomical preservation of hearing. State-of-the-art surgical instruments in specimens with suitable anatomy are sufficient to perform this approach.

Thyroid Gland Flap for Prevention of Pharyngocutaneous Fistula After Total Laryngectomy.

Pharyngocutaneous fistula (PCF) is the one of the major complications after total laryngectomy (TL), which can result in saliva leakage, rupture of major vessels, and increased hospitalization. Several flaps have been tried to prevent PCF during TL, and they are usually associated with donor site morbidity and uncertain viability in case of previously irradiated patients. This study aimed to report a novel bilateral pedicled thyroid gland flap (TGF) technique for delicate and effective reinforcement of neopharynx suture line after TL. Bilateral pedicled TGF was performed for the reinforcement of neopharynx T-shape suture sites after TL in this case series. A total of five cases of the TGF were performed during TL, with four of them being salvage setting following previous chemoradiation therapy (CRT). The well-adapted and viable TGF status was confirmed by post-operative computed tomography scan and normally preserved thyroid hormone levels in all patients. No post-operative infections, hemorrhage, hypothyroidism, hypoparathyroidism, or PCF were reported. The TGF is an effective and reliable flap in TL patents and should be considered as a method in neopharynx reconstruction, even in salvage TL following prior CRT.

Large Fenestrations Versus Scallops for the Superior Mesenteric Artery during Fenestrated Endovascular Aneurysm Repair: Does it Matter?

Fenestrated endovascular aneurysm repair is an established customized treatment for aortic aneurysms with 3 current commercially available configurations for the superior mesenteric artery (SMA)-a single-wide scallop, large fenestration, or small fenestration, with the scallop or large fenestration most utilized. Outcomes comparing SMA single-wide scallops to large fenestrations with the Zenith fenestrated (ZFEN) device are scarce. As large fenestrations have the benefit of extending the proximal seal zone compared to scalloped configurations, we sought to determine the differences in seal zone and sac regression outcomes between the 2 SMA configurations. We retrospectively reviewed our prospectively maintained complex endovascular aneurysm repair database and included all patients treated with the Cook ZFEN device with an SMA scallop or large fenestration configuration at its most proximal build. All first postoperative computed tomography scans (1-30days) were analyzed on TeraRecon to determine precise proximal seal zone lengths, and standard follow-up anatomic and clinical metrics were tabulated. A total of 234 consecutive ZFEN patients from 2012 to 2021 were reviewed, and 137 had either a scallop or a large fenestration for the SMA as the proximal-most configuration (72 scallops and 65 large fenestrations) with imaging available for analysis. The mean follow-up was 35months. The mean proximal seal zone length was 19.5±7.9mm for scallop versus 41.7±14.4mm for large fenestration groups (P<0.001). There was no difference in sac regression between the scallop and large fenestration at 1year (10.1±10.9mm vs. 11.0±12.1, P=0.63). Overall, 30-day mortality (1.3% vs. 2.5%, P=0.51) and all-cause 3-year mortality (72.5% vs. 81.7%, P=0.77) were not significantly different. Reinterventions within 30days were primarily secondary to renal artery branch occlusions, with only 1 patient in the scallop group requiring reintervention for an SMA branch occlusion. Despite attaining longer proximal seal lengths, large SMA fenestrations were not associated with a difference in sac regression compared to scalloped SMA configurations at a one-year follow-up. There were no significant differences in reinterventions or overall long-term survival between the 2 SMA strategies.