Spinal Fixation Surgery Research Articles

Posterolateral full-endoscopic debridement and irrigation is effective in treating thoraco-lumbar pyogenic spondylodiscitis, except in cases with large abscess cavities.

To determine the efficacy and poor prognostic factors of posterolateral full-endoscopic debridement and irrigation (PEDI) surgery for thoraco-lumbar pyogenic spondylodiscitis. We included 64 patients (46 men, 18 women; average age: 63.7years) with thoracic/lumbar pyogenic spondylodiscitis who had undergone PEDI treatment and were followed up for more than 2years. Clinical outcomes after PEDI surgery were retrospectively investigated to analyze the incidence and risk factors for prolonged and recurrent infection. Of 64 patients, 53 (82.8%) were cured of infection after PEDI surgery, and nine (17.2%) had prolonged or recurrent infection. Multivariate analysis demonstrated that significant risk factors for poor prognosis included a large intervertebral abscess cavity (P = 0.02) and multilevel intervertebral infections (P < 0.05). PEDI treatment is an effective, minimally invasive procedure for pyogenic spondylodiscitis. However, a large intervertebral abscess space could cause instability at the infected spinal column, leading to prolonged or recurrent infection after PEDI. In cases with a large abscess cavity with or without vertebral bone destruction, endoscopic drainage alone may have a poor prognosis, and spinal fixation surgery could be considered.

Prevention of Compression Fracture in Osteoporosis Patients under Minimally Invasive Trans-Foraminal Lumbar Interbody Fusion with Assistance of Bone-Mounted Robotic System in Two-Level Degenerative Lumbar Disease.

Background and Objectives: Minimally invasive spine surgery reduces destruction of the paraspinal musculature and improves spinal stability. Nevertheless, screw loosening remains a challenging issue in osteoporosis patients receiving spinal fixation and fusion surgery. Moreover, adjacent vertebral compression fracture is a major complication, particularly in patients with osteoporosis. We assessed long-term imaging results to investigate the outcomes of osteoporosis patients with two-level degenerative spine disease receiving minimally invasive surgery with the assistance of a robotic system. Materials and Methods: We retrospectively analyzed consecutive osteoporosis patients who underwent minimally invasive surgery with the assistance of a robotic system at our institution during 2013–2016. All patients were diagnosed with osteoporosis according to the World Health Organization criteria. All patients were diagnosed with two levels of spinal degenerative disease, including L34, L45, or L5S1. The study endpoints included screw-loosening condition, cage fusion, and vertebral body heights of the adjacent, first fixation segment, and second fixation segments before and after surgery, including the anterior, middle, and posterior third parts of the vertebral body. Differences in vertebral body heights before and after surgery were evaluated using the F-test. Results: Nineteen consecutive osteoporosis patients were analyzed. A lower rate of screw loosening was observed in osteoporosis patients in our study. There were no significant differences between the preoperative and postoperative vertebral body heights, including adjacent and fixation segments. Conclusions: According to our retrospective study, we report that minimally invasive surgery with the assistance of a robotic system provided better screw fixation, a lower rate of screw loosening, and a lesser extent of vertebral compression fracture after spinal fixation and fusion surgery in osteoporosis patients.

The effects of combined microwave ablation and open surgery for the treatment of lung cancer-derived thoracolumbar metastases.

ObjectiveTo investigate the clinical effects of microwave ablation (MWA) in addition to open surgery for the treatment of lung cancer‐derived thoracolumbar metastases.MethodsThis was a single‐institution, retrospective, cohort study. From January 2019 to December 2020, a total of 47 patients with lung cancer‐derived thoracolumbar metastases underwent posterior spinal canal decompression and fixation surgery in our hospital. Two independent surgical teams treated these patients. One group underwent open surgery combined with MWA therapy, while the other had open surgery only (control). The pre‐ and post‐operative visual analog scale (VAS) scores and the overall survival (OS) were compared between the MWA and control groups. The Frankel Grade classification was applied for the evaluation of the post‐surgical spinal cord function. Improvement was defined as an increase of at least one rank from the pre‐operative scores. Each patient was evaluated pre‐ and post‐operatively at 48 h, 1 month, and 3‐month intervals. Data on surgical‐related complications were recorded.ResultsThirty men and 17 women were included, with an average age of 57.9 ± 11.4 years (range, 26–81 years). Twenty‐eight patients underwent MWA and were in the MWA group, and 19 patients were included in the control group. Post‐operatively all patients were followed up regularly; the median follow‐up time was 12 months (range, 3–24 months), and their median OS was 14 months. Patients in the MWA group had a lower VAS score than those in the control group at the 48‐h (1.75 ± 1.01 vs 2.47 ± 0.96, P = 0.01) and 1‐month (1.79 ± 0.92 vs 2.53 ± 1.35, P = 0.048) check‐ups. At the 3‐month evaluation, the VAS score differences between the two groups were not significant (P = 0.133). After surgery, spinal cord function improvement was not significantly different between the MWA and control groups (P = 0.515). MWA therapy combined with open surgery was not associated with increased OS compared with the control group (P = 0.492).ConclusionMWA can be an effective and safe pain‐relief method but may not extend the OS of patients with lung cancer.

Effect of continuous intra-incisional bupivacaine on postoperative pain in non-traumatic spinal fixation surgeries: a randomized controlled trial

BackgroundContinuous injection of local anesthetics by using surgical wound catheters for postoperative pain relief has gained acceptance in recent years. However, whether this method can be alternatively used instead of systemic opioids in different surgical procedures has not yet been elucidated. ObjectivesThe aim was to investigate the effect of continuous injection of bupivacaine through a catheter inside the surgical wound on reducing the postoperative pain of lumbar spine fusion surgeries. MethodsIn this clinical trial, 31 patients undergoing non-traumatic lumbar spine stabilization surgery were randomly assigned to receive (n = 15) or do not receive (n = 16) bupivacaine through a catheter inside the surgical wound, postoperatively. Pain intensity (NRS), dose of required morphine, and drug-related complications within 24 hours of intervention were assessed and compared by the Mann-Whitney and independent t-test. ResultsMean pain intensity was significantly lower in the case group over the first postoperative hour in the recovery room (p < 0.001), which continued for the first 2 hours after entering the ward. The mean morphine intake was lower in the bupivacaine group during the first postoperative 24 hours (16 ± 0.88 vs. 7.33 ± 0.93 mg, p < 0.001). The two groups were not significantly different regarding drug-related complications. ConclusionContinuous intra-incisional infusion of bupivacaine helped better pain reduction during the early postoperative hours while sparing morphine consumption in the first postoperative day.

Albee spinal osteoplastic fixation surgery

Operation of osteoplastic fixation of the spine according to Albee, performed by Baer'om (Bull, of the Johns Hopkins Hosp., Vol. 33, No. 374, p. 140-142, 1922) in 50 cases, led V. to the following conclusion

Risk factors for screw loosening in patients with adult degenerative scoliosis: the importance of paraspinal muscle degeneration

BackgroundParaspinal muscle is an important component to maintain spinal stability. But the relationship between the degeneration of paraspinal muscle and postoperative screw loosening in patients with adult degenerative scoliosis has not been studied. The objective of this study was to investigate risk factors for screw loosening in patients with adult degenerative scoliosis, including paraspinal muscle degeneration.MethodsWe investigated 93 patients with adult degenerative scoliosis who underwent spinal interbody fusion and pedicle screw fixation surgery. The lateral curvature was located in the lumbar spine and the follow-up time was ≥ 2 years. The patients were divided into loosening and non-loosening groups. Screw loosening was defined as a 1-mm or wider circumferential radiolucent line around the pedicle screw. We checked the cross-sectional area of paraspinal muscles, spinopelvic parameters, bone mineral density, number of fusion segment, and other factors. The potential risk factors for screw loosening were investigated by using binary logistical regression analysis.ResultsFifty-seven patients showed screw loosening, which is 63.4% of total. Compared with patients in the non-loosening group, the cross-sectional area of erector spinae and psoas major muscle at L5 level were significantly smaller in patients with screw loosening (P < 0.05). Among these factors, the number of fused segments and relative erector spinae total cross-sectional area were independent risk factors for screw loosening.ConclusionsThe degeneration of paraspinal muscle and the increase of fusion segment were independent factors for screw loosening in patients with adult degenerative scoliosis.

Spinal Pedicle Morphometry using Multidetector CT—An experience from the Indian Subcontinent

Abstract Introduction For safe pedicle screws placement, knowledge of pedicle morphometry is essential, because an inconsistency between pedicle width and the screw diameter may lead to severe complications like nerve, vessel or visceral injuries. Objectives To study the spinal pedicle width and height of lumbar spine, using multidetector CT (MDCT), among the Indian population. To study the spinal pedicle angulation of lumbar spine, using MDCT, among the Indian population. Method The study was conducted at a tertiary care multispecialty hospital. In the present study, a total of 321 patients were included, who underwent MDCT scan without contrast at our institution, over a period of 2 years, from May 2017 to May 2019. The study population (n = 321) was divided into different subgroups on the basis of the age. The data was taken from the workstation. Comparison was made separately between each subgroup. Results In our subset of population, the 10 to 90 years age group, pedicle dimensions are as follow: The pedicle diameter from L1 to L5 is 4.46 to 11.92 mm. The pedicle height from L1 to L5 is 7.38 to 11.01 mm. The pedicle axial angulation from L1 to L5 is 22.27 to 36.08 degree. The pedicle lateral angulation from L1 to L5 is 16.12 to 22.47 degree. Conclusion Knowledge of the pedicle morphometry (pedicle width, height and angulation) of lumbar spine will help the neurosurgeons standardize the size of pedicle screws which is required for spinal fixation surgery at various lumbar vertebra levels.

Multimodal treatment including lumbar facet joint denervation for severe low back pain in patients with neuromuscular disorders.

Severe low back pain (LBP) is an occasional complaint in patients with neuromuscular disorders (NMDs). Accurate diagnosis and treatment are required to manage LBP; however, the precise pathophysiology differs for each patient. This study aimed to evaluate the efficacy of lumbar facet joint denervation (FJD) and adjunctive modalities in the treatment of LBP in patients with NMD-associated kyphoscoliosis. A total of 16 patients (22 sites) with NMD (bilateral, n = 6; unilateral, n = 10) and LBP treated with lumbar FJD were evaluated. The patients were divided into two groups: those treated with FJD alone (group 1) and those treated with multimodal treatment, including FJD along with radiofrequency ablation for sacroiliac joint pain, piriform muscle block, botulinum toxin injection into the paraspinal muscles, spinal cord stimulation, or any of their combinations (group 2). All patients were followed up for 48 weeks postoperatively. The two groups were compared with respect to the duration required for improvements in LBP by more than 50% (numerical rating scale ≤ 5). There was no significant difference between the groups regarding the age, duration since the onset of Parkinson's syndrome, and radiographic analysis. The effective period of improved pain was greater in group 2 than in group 1 (30.7 vs. 8.4 weeks, P < 0.01). Multimodal treatment including FJD is safe and relatively effective in patients with NMD-associated kyphoscoliosis. Hence, it is a potential substitute for conventional spinal fixation surgery, which has a higher risk of complications.

Spondylodiscitis treated with freeze-dried bone allograft alone or combined with autograft: A randomized and blinded trial.

To compare the bone fusion of freeze-dried allograft alone versus freeze-dried allograft combined autograft in spinal instrumentation due to spondylodiscitis. A randomized prospective trial of patients with spondylodiscitis treated with surgical debridement and spinal fixation with freeze-dried bone allograft and autograft (Group 1) or freeze-dried bone allograft alone (Group 2) was performed. Patient follow-up was assessed with a CT-scan for bone fusion; consecutive serum inflammatory marker detection (C-reactive protein, [CRP], and erythrocyte sedimentation rate, [ESR]) and clinical assessment (pain, functional disability, and spinal cord injury recovery) were other outcome parameters. The primary outcome was the grade of bone allograft integration with the scale of Tan (which ranges from 1 to 4, with lower scores indicating a better fusion rate) at 1 year after surgery. A total of 20 patients were evaluated, 13 (65%) men and 7 (35%) women with a mean age of 47.2 (±14.3) years. Homogeneous distribution of demographic data was observed. A similar satisfactory bone graft fusion grade was observed in both graft groups at 1 year after surgery (p = 1.0000). Serum inflammatory markers gradually decreased in both groups after surgical intervention (CRP, p < 0.001; ESR, p < 0.01). At one-year follow-up, gradual improvement of pain, functional disability, and neurological spinal injury recovery in both graft groups were achieved. Freeze-dried allograft alone could be a therapeutic option for spinal fixation surgery due to spondylodiscitis since it achieves a satisfactory graft fusion rate and clinical improvement. Level 1. Treatment. NCT03265561.

Predicting the Failure Risk of Internal Fixation Devices in Chinese Patients Undergoing Spinal Internal Fixation Surgery: Development and Assessment of a New Predictive Nomogram.

The current study is aimed at developing and validating a nomogram of the risk of failure of internal fixation devices in Chinese patients undergoing spinal internal fixation. We collected data from a total of 1139 patients admitted for spinal internal fixation surgery at the First Affiliated Hospital of Guangxi Medical University from May 2012 to February 2019. Of these, 1050 patients were included in the spinal internal fixation group and 89 patients in the spinal internal fixation device failure group. Patients were divided into training and validation tests. The risk assessment of the failure of the spinal internal fixation device used 14 characteristics. In the training test, the feature selection of the failure model of the spinal internal fixation device was optimized using the least absolute shrinkage and selection operator (LASSO) regression model. Based on the characteristics selected in the LASSO regression model, multivariate logistic regression analysis was used for constructing the model. Identification, calibration, and clinical usefulness of predictive models were assessed using C-index, calibration curve, and decision curve analysis. A validation test was used to validate the constructed model. In the training test, the risk prediction nomogram included gender, age, presence or absence of scoliosis, and unilateral or bilateral fixation. The model demonstrated moderate predictive power with a C-index of 0.722 (95% confidence interval: 0.644–0.800) and the area under the curve (AUC) of 0.722. Decision curve analysis depicted that the failure risk nomogram was clinically useful when the probability threshold for internal fixation device failure was 3%. The C-index of the validation test was 0.761. This novel nomogram of failure risk for spinal instrumentation includes gender, age, presence or absence of scoliosis, and unilateral or bilateral fixation. It can be used for evaluating the risk of instrumentation failure in patients undergoing spinal instrumentation surgery.

Adjacent segment disease on hip joint as a complication of spinal fusion surgery including sacroiliac joint fixation.

Recently, the number of adult spinal deformity surgeries including sacroiliac joint fixation (SIJF) by using an S2 alar iliac screw or iliac screw has increased to avoid the distal junctional failure. However, we occasionally experienced patients who suffered from hip pain after a long instrumented spinal fusion. We hypothesized that long spinal fusion surgery including SIJF influenced the hip joint as an adjacent joint. The aim of this paper was to evaluate the association between spinal deformity surgery including SIJF and radiographic progression of hip osteoarthritis (OA). This study was retrospective cohort study. In total, 118 patients who underwent spinal fusion surgery at single center from January 2013 to August 2018 were included. We measured joint space width (JSW) at central space of the hip joint. We defined reduction of more than 0.5mm/year in JSW as hip OA progression. The patients were divided into two groups depending on either a progression of hip osteoarthritis (Group P), or no progression (Group N). The number of patients in Group P and Group N was 47 and 71, respectively. Factor that was statistically significant for hip OA was SIJF (p = 0.0065, odds ratio = 7.1, 95% confidence interval = 1.6-31.6). There were no other significant differences by the multiple logistic regression analysis. This study identified spinal fixation surgery that includes SIJF as a predictor for radiographic progression of hip OA over 12months. We should pay attention to hip joint lesions after adult spinal deformity surgery, including SIJF.

A Tailored Approach to Cortical Bone Track for Spine Fixation Surgery: 3-Dimensional Printed Custom Made Guides for Screws Placement: 2-Dimensional Operative Video.

Cortical bone trajectory (CBT) screw fixation is an attractive technique.1-4 However, the ideal insertion of those screws could be technically demanding.5,6 The use of 3-dimensional (3D) patient-matched guides increase safety for CBT screws implantation.7 In this video, the case of a 46 yr old male is presented. He complained low back pain with left sciatica. magnetic resonance imaging showed an L5/S1 degenerative disc disease with left herniation. The patient was positioned prone; the L5 spinous process was identified under fluoroscopic guidance than skin incision was performed. Preserving the cranial facet joints, spinous processes and laminae of L5 and S1 vertebrae were exposed. Guides were positioned on the corresponding vertebra and the contact areas checked to avoid any discrepancy. With a high-speed drill the cortical bone was violated through the guide tubes. The drill itself has a stop mechanism provided by the guides. With this mechanism the drilling can be safely performed up to the planned depth. Guidewires were than introduced into the pedicle and body of the vertebra; undertapping could be performed with cannulated instrument. Laminectomy and facetectomy were performed. Diskectomy was performed, then a titanium kidney-shaped pivoting cage was implanted. Four Screws were finally placed. Proper positioning of the implants were verified on fluoroscopy and on the postoperative computed tomography scan confirming the accuracy of the trajectory. All procedures performed for this study were in accordance with the ethical standards of our Institute and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Written informed consent was obtained from the patient who is operated in this video.

Intraoperative cone beam computed tomography is as reliable as conventional computed tomography for identification of pedicle screw breach in thoracolumbar spine surgery

ObjectivesTo test the hypothesis that intraoperative cone beam computed tomography (CBCT) using the Allura augmented reality surgical navigation (ARSN) system in a dedicated hybrid operating room (OR) matches computed tomography (CT) for identification of pedicle screw breach during spine surgery.MethodsTwenty patients treated with spinal fixation surgery (260 screws) underwent intraoperative CBCT as well as conventional postoperative CT scans (median 12 months after surgery) to identify and grade the degree of pedicle screw breach on both scan types, according to the Gertzbein grading scale. Blinded assessments were performed by three independent spine surgeons and the CT served as the standard of reference. Screws graded as Gertzbein 0 or 1 were considered clinically accurate while grades 2 or 3 were considered inaccurate. Sensitivity, specificity, and negative predictive value were the primary metrics of diagnostic performance.ResultsFor this patient group, the negative predictive value of an intraoperative CBCT to rule out pedicle screw breach was 99.6% (CI 97.75–99.99%). Among 10 screws graded as inaccurate on CT, 9 were graded as such on the CBCT, giving a sensitivity of 90.0% (CI 55.5–99.75%). Among the 250 screws graded as accurate on CT, 244 were graded as such on the CBCT, giving a specificity of 97.6% (CI 94.85–99.11%).ConclusionsCBCT, performed intraoperatively with the Allura ARSN system, is comparable and non-inferior to a conventional postoperative CT scan for ruling out misplaced pedicle screws in spinal deformity cases, eliminating the need for a postoperative CT.Key Points• Intraoperative cone beam computed tomography (CT) using the Allura ARSN is comparable with conventional CT for ruling out pedicle screw breaches after spinal fixation surgery.• Intraoperative cone beam computed tomography can be used to assess need for revisions of pedicle screws making routine postoperative CT scans unnecessary.• Using cone beam computed tomography, the specificity was 97.6% and the sensitivity was 90% for detecting pedicle screw breaches and the negative predictive value for ruling out a pedicle screw breach was 99.6%.

Clinical Correlation of Intraoperative Neuromonitoring in 319 Individuals Undergoing Posterior Decompression and Fixation of Spine.

This was a prospective study. To correlate improvement in motor evoked potential (MEP) during spine surgery with postoperative clinical improvement. Three hundred fifty-three patients operated for posterior spinal decompression and fixation surgeries were prospectively selected and followed up. Patients who underwent lumbar, dorsal, and cervical surgeries were grouped into-group A, B, and C, respectively. Intraoperative neuromonitoring was done using MEP with free-running electromyography. Improvements in MEP scores were calculated in percentage. Similarly, postoperative improvement in Oswestry disability index (ODI) and visual analog scale (VAS) scores at 3 months were calculated in percentage. Improvements in MEP scores were correlated with clinical improvement using the Spearman ρ test and the r value was calculated to find out the association. Of 353 patients, 319 (250-group A, 38-group B, and 31-group C) were included for the study. VAS and ODI improved significantly from preoperative 8.5±0.8 and 62.9±14.5, to postoperative 2.3±1.1 and 15.9±11.5, respectively, in the entire group. Average preoperative MEP were 127.8±191.0 mV on the right side and 132.3±206.6 mV on the left side, which significantly improved to 163.7±231.2 mV (P=0.0001) and 155.2±219.6 mV (P=0.0001), respectively, showing 157.0% and 178.5% improvement. Correlating MEP improvement with postoperative improvement in ODI showed poor correlation (r=0.088 right and 0.030 left sides). Similarly, correlating MEP improvement with improvement in VAS showed r=0.110 on the right and -0.023 on the left side suggesting poor correlation. Postoperative neurological complications (0.56%) were found in 2 patients in the form of screw malpositioning. Intraoperative neuromonitoring showed significant improvement during posterior decompression and fixation surgery, and reduction in postoperative neurological complication. The study also exhibited significant postoperative clinical improvement. However, improvement in MEP did not correlate with postoperative clinical improvement suggesting that it has no predictive role.

Prediction of Pelvic Inclination in the Sitting Position after Corrective Surgery for Adult Spinal Deformity.

Introduction Hip dislocation rates in patients with combined total hip arthroplasty (THA) and spinal deformity fixation are significantly higher than those of THA alone. Nevertheless, there are no treatment recommendations for patients who undergo THA and require a spine deformity correction later. Methods Twenty-eight patients underwent spinal fixation surgery for adult spinal deformity. Sagittal spinopelvic alignment was analyzed on lateral radiographs taken preoperatively and postoperatively in the sitting and standing positions. Univariate linear regression analysis was conducted to identify the factors affecting the pelvic inclination in the sitting position after spinal fixation. Multiple regression analysis was conducted to determine the most efficient combination of radiographic parameters for predicting postoperative pelvic inclination while sitting. Results There were significantly weak associations between postoperative sacral slope (SS) in the sitting position and the following factors: the number of vertebral levels fused (β = 0.30, p = 0.003); the presence of sacral fixation (β = 0.22, p = 0.01); the presence of sacroiliac joint fixation (β = 0.24, p = 0.008); and preoperative SS while standing and sitting (β = 0.21, p = 0.01 and β = 0.34, p = 0.001). Postoperative lumbar lordosis (LL) while standing was strongly associated with postoperative SS in the sitting position (β = 0.67, p <.0001). The combination of postoperative LL in the standing position and preoperative SS in the sitting position was the best fit, and the adjusted R-squared was 0.82. Conclusions We devised a prediction formula for pelvic inclination while sitting after spinal fixation that has high predictability: postoperative SS while sitting = 11.7+ (0.4 × postoperative planned LL while standing) + (0.16 × preoperative SS while sitting). This study could be the basis for treatment recommendations for patients who have undergone THA and require a spine deformity correction later.

Additive manufacturing of compositionally graded laser deposited titanium-chromium alloys

Ti-xCr (9 ≤ x ≤ 28) at% graded alloys fabricated via laser engineered net shaping (LENS™) are potential candidate materials for graded implants in spinal fixation surgeries due to their tunable Young’s modulus. This is achievable by various phase transformations on the laser deposited graded alloys by subjugating them to different β-solutionizing heat treatments. The microstructure of the as-deposited (AD) Ti-xCr alloy was comprised of a metastable β-Ti(Cr) matrix phase along with α-Ti and TiCr2 (an intermetallic Laves phase) at different regions of the graded alloy. In comparison, the microstructure of the rapidly air cooled (RAC) Ti-xCr alloy contained ω and TiCr2 precipitate phases, while the slowly furnace cooled (SFC) Ti-xCr alloy has α-Ti and TiCr2 precipitate phases along different regions of the graded alloys. An extreme change in micro-hardness values at different regions of the RAC and SFC alloys due to these various phase transformations indicates that the alloy fabricated may be qualified as a potential graded implant material. Additionally, the phase evolution along the compositional gradient of the AD Ti-xCr alloy was correlated to theories of reheating in the lower build layers, thermal gradient effect, rapid solidification rates, and enthalpy of mixing between Ti-Cr powders. A detailed explanation to variation in microstructures and mechanical properties observed at compositions of Ti∼29at%Cr (a lower build layer) and Ti∼28at%Cr (an upper build layer) in the AD Ti-xCr graded alloy is also provided.

Augmented reality navigation with intraoperative 3D imaging vs fluoroscopy-assisted free-hand surgery for spine fixation surgery: a matched-control study comparing accuracy

This study aimed to compare screw placement accuracy and clinical aspects between Augmented Reality Surgical Navigation (ARSN) and free-hand (FH) technique. Twenty patients underwent spine surgery with screw placement using ARSN and were matched retrospectively to a cohort of 20 FH technique cases for comparison. All ARSN and FH cases were performed by the same surgeon. Matching was based on clinical diagnosis and similar proportions of screws placed in the thoracic and lumbosacral vertebrae in both groups. Accuracy of screw placement was assessed on postoperative scans according to the Gertzbein scale and grades 0 and 1 were considered accurate. Procedure time, blood loss and length of hospital stay, were collected as secondary endpoints. A total of 262 and 288 screws were assessed in the ARSN and FH groups, respectively. The share of clinically accurate screws was significantly higher in the ARSN vs FH group (93.9% vs 89.6%, p < 0.05). The proportion of screws placed without a cortical breach was twice as high in the ARSN group compared to the FH group (63.4% vs 30.6%, p < 0.0001). No statistical difference was observed for the secondary endpoints between both groups. This matched-control study demonstrated that ARSN provided higher screw placement accuracy compared to free-hand.

Computed Tomography-Based Preoperative Simulation System for Pedicle Screw Fixation in Spinal Surgery.

BackgroundA preoperative planning system facilitates improving surgical outcomes that depend on the experience of the surgeons, thanks to real-time interaction between the system and surgeons. It visualizes intermediate surgical planning results to help surgeons discuss the planning. The purpose of this study was to demonstrate the use of a newly-developed preoperative planning system for surgeons less experienced in pedicle-screw fixation in spinal surgery, especially on patients with anatomical variations.MethodsThe marching cubes algorithm, a typical surface extraction technique, was applied to computed tomography (CT) images of vertebrae to enable three-dimensional (3D) reconstruction of a spinal mesh. Real-time processing of such data is difficult, as the surface mesh extracted from high-resolution CT data is rough, and the size of the mesh is large. To mitigate these factors, Laplacian smoothing was applied, followed by application of a quadric error metric-based mesh simplification to reduce the mesh size for the level-of-detail (LOD) image. Taubin smoothing was applied to smooth out the rough surface. On a multiplanar reconstruction (MPR) cross-sectional image or a 3D model view, the insertion position and orientation of the pedicle screw were manipulated using a mouse. The results after insertion were then visualized in each image.ResultsThe system was used for pre-planning pedicle-screw fixation in spinal surgery. Using any pointing device such as a mouse, surgeons can manipulate the position and angle of the screws. The pedicle screws were easy to manipulate intuitively on the MPR images, and the accuracy of screw fixation was confirmed on a trajectory view and 3D images. After surgery, CT scans were performed again, and the CT images were checked to ensure that the screws were inserted properly.ConclusionThe preoperative planning system allows surgeons and students who are not familiar with pedicle-screw fixation to safely undertake surgery following preoperative planning. It also provides opportunities for screw-fixation training and simulation.

Safety of gabapentin versus celecoxib as a part of multimodal analgesia in patients with elective spine fixation surgery, A comparative randomized control study

Safety of gabapentin versus celecoxib as a part of multimodal analgesia in patients with elective spine fixation surgery, A comparative randomized control study

Diffuse reflectance spectroscopy accurately identifies the pre-cortical zone to avoid impending pedicle screw breach in spinal fixation surgery.

Pedicle screw placement accuracy during spinal fixation surgery varies greatly and severe misplacement has been reported in 1-6.5% of screws. Diffuse reflectance (DR) spectroscopy has previously been shown to reliably discriminate between tissues in the human body. We postulate that it could be used to discriminate between cancellous and cortical bone. Therefore, the purpose of this study is to validate DR spectroscopy as a warning system to detect impending pedicle screw breach in a cadaveric surgical setting using typical clinical breach scenarios. DR spectroscopy was incorporated at the tip of an integrated pedicle screw and screw driver used for tissue probing during pedicle screw insertions on six cadavers. Measurements were collected in the wavelength range of 400-1600 nm and each insertion was planned to result in a breach. Measurements were labelled as cancellous, cortical or representing a pre-cortical zone (PCZ) in between, based on information from cone beam computed tomographies at corresponding positions. In addition, DR spectroscopy data was recorded after breach. Four typical pedicle breach types were performed, and a total of 45 pedicle breaches were recorded. For each breach direction, the technology was able to detect the transition of the screw tip from the cancellous bone to the PCZ (P < 0.001), to cortical bone (P < 0.001), and to a subsequent breach (P < 0.001). Using support vector machine (SVM) classification, breach could reliably be detected with a sensitivity of 98.3 % [94.3-100 %] and a specificity of 97.7 % [91.0-100 %]. We conclude that DR spectroscopy reliably identifies the area of transition from cancellous to cortical bone in typical breach scenarios and can warn the surgeon of impending pedicle breach, thereby resulting in safer spinal fixation surgeries.