Posterior Instrumentation Surgery Research Articles

The effect of the size of pedicle screw on the long-term radiological and clinical results of short-segment posterior instrumentation in the management of thoracolumbar vertebral fractures.

It was aimed at evaluating the effect of the size of the pedicle screw placed on the fractured vertebra on the long-term radiological and clinical results of short-segment posterior instrumentation applied in the surgical treatment of thoracolumbar vertebral fractures. This retrospective study included 36 patients who underwent short-segment posterior instrumentation surgery for a single-level thoracolumbar (T11-L2) fracture between January 2015 and March 2021. The patients included in the study were divided into 2 groups according to the size of the pedicle screw placed in the fractured vertebra (group A: intermediate screw 4.5 mm, ≤35 mm+less than 50% of the vertebral corpus length, m/f: 13/4, n: 17, age: 36.5; group B: intermediate screw 5.5 mm, ≥40 mm+more than 70% of the vertebral corpus length, m/f: 11/8, n: 19, age: 42.6). All patients were periodically evaluated clinically and radiologically. Vertebral compression angle (VCA), anterior and posterior vertebral body height (ABH-PBH), intraoperative parameters (instrumentation time and intraoperative fluoroscopy number), and complications were compared between the 2 groups. Both groups were comparable with respect to age, sex, level of injury, AO classification, mechanism of injury, and American Spinal Cord Injury Association impairment scale. Restoration of VCA and vertebral corpus heights was achieved sufficiently in both groups after operation (P < .0001). There was no significant difference between the 2 groups in terms of early postoperative VCA, VCA measured at final follow-up, or loss of correction in VCA. At the last follow-up, PBH was statistically significantly better preserved in group B (P=.0424). There was no difference between the 2 groups in terms of operation time and the number of intraoperative fluoroscopies. Implant failure was observed in 1 patient in group A. This study has revealed that using a long, thick pedicle screw placed in the fractured vertebra can better preserve the PBH at the final follow-up. No correlation was found between the size of the intermediate screw and the preservation of the correction in the postoperative vertebral heights and VCA during the follow-up. Level III, Therapeutic Study.

Radiologic Examination of High Riding Vertebral Artery and Analysis of Secure Areas

ObjectiveTo radiologically examine the pedicle, lamina, and vertebral artery foraminal anatomies at the C2 vertebra for pedicular and laminar screw instrumentation at the axis in a Turkish population. Materials and MethodsFrom 2018 to 2019, we evaluated 100 patients who underwent cervical computed tomography (CT) for various reasons (excluding cervical pathologies) at Marmara University Hospital. The C2 pedicles were measured on CT images using measurement tools. In addition, axial computed tomography was performed at 0.1-mm intervals. Bilateral measurements were performed for each case. ResultsThe median right and left pedicle axial diameters were respectively 5.01 and 5.09 mm for the male patients and 4.31 and 4.38 mm for the female patients, showing a statistically significant difference between the sexes (p < 0.01). Of the patients, 15% had narrow pedicles. The pedicle sagittal diameters were smaller than 5 mm in 30% of the computed tomographic series. The internal height was <2 mm in 4% of the cases. ConclusionOur findings suggest significant individual and sex-related differences. Vertebral artery groove anomalies are commonly observed. Before performing a posterior craniocervical instrumentation surgery, a CT examination is beneficial because high-riding vertebral arteries must be kept in mind in determining the appropriate screw diameter and screw trajectory.

Comparison of the Postoperative Analgesia Effects of Patient-Controlled Analgesia and Epidural Catheter After Posterior Instrumentation Surgery

Objective: To prospectively assess the effects of intravenous patient-controlled analgesia (IV PCA) and epidural patient-controlled analgesia (epidural PCA) on postoperative pain management following posterior instrumentation surgery.&#x0D; Materials and Methods: The study involved the ASA 1-2 group, 60 patients who underwent elective thoracic or lumbar posterior instrumentation surgery at our tertiary centre for spinal stenosis. Two groups of patients were created: Group 1 (n = 30), IV PCA group, and Group 2 (n=30), epidural PCA group. IV PCA was applied by fentanyl. Epidural PCA was maintained by lading to epidural space by the neurosurgeon. Bupivacaine was administered to Group 2 patients in the recovery room. Following surgery, patients in both groups were assessed for pain using the visual analogue scale (VAS) and for motor block using the Bromage scale. Additionally, hemodynamic parameters, side effects, and patient satisfaction were noted. Following 48 hours, patients' overall rescue analgesia, opioid, and local anaesthetic requirements were recorded. &#x0D; Results: Postoperative VAS scores of Group 2 at the 1st, 2nd, 4th, 8th and 16th hours were lower than Group 1 and these differences was statistically significant. Postoperative patient satisfaction scores at 1st, 2nd, 4th, 8th, 12th, 16th, 20th, 24th, 30th, 36th, 42nd and 48th hours were significantly different between the groups and the patient satisfaction scores of Group 2 were higher than the Group 1. Side effects were similar in both groups. Group 1 required statistically significantly higher number of rescue analgesia. &#x0D; Conclusion: This study shows that epidural PCA is more comfortable than IV PCA with low VAS and high patient satisfaction scores. As a conclusion, epidural PCA is a safe, highly efficient method for patients with posterior instrumentation surgery.

Effect of pre-operative HbA1c and blood glucose level on the surgical site infection after lumbar instrumentation surgery

BackgroundThis study aims to investigate the effect of pre-operative hemoglobin A1c (HbA1c) and pre-operative blood glucose control on the rate of surgical site infection (SSI) after posterior lumbar instrumentation surgery in diabetes mellitus (DM) patients. MethodsA total of 1046 patients who had undergone posterior lumbar instrumentation surgery were reviewed. Based on pre-operative HbA1c, patients were divided into three groups: non-DM group, low HbA1c group (HbA1c < 7.0 % in DM) and high HbA1c group (≥7.0). As well, based on the status of blood glucose control in DM patients immediately before surgery, patients were divided into two groups: good control group (post-prandial blood glucose [PBG] < 200 mg/dl) and poor control group (≥200). The rate of SSI was compared among these groups. ResultsSSI occurred in 1.9 % in non-DM group, 2.4 % in low HbA1c group, and 9.3 % in high HbA1c group. Compared with non-DM group, high HbA1c group had significantly higher rate of SSI (p = 0.001). There was not statistically different between non-DM and low HbA1c groups (p = 0.550). SSI occurred in 2.2 % in good control group, and 10.2 % in poor control group. The rate of SSI was significantly lower in good control group (p = 0.013). ConclusionThis study showed that the rate of SSI after posterior lumbar instrumentation surgery tend to be higher in DM patients with high HbA1c. However, the rate might be reduced to the same level as that of non-DM group by lowering PBG to <200 mg/dl immediately before surgery.

Value of multi-channel somatosensory evoked potentials recording in patients undergoing scoliosis correction surgery.

We aimed to investigate the value of intraoperative multi-channel recording of somatosensory evoked potentials (SSEPs) in patients undergoing posterior instrumentation surgery with fusion. This study included 176 patients with scoliosis who underwent posterior correction surgery from January 2019 to June 2020. Among them, 88 patients underwent routine SSEPs monitoring via single-channel (Cz'-Fpz) cortical recording (control group), while the remaining 88 patients underwent multi-channel (Cz'-Fpz and C3'-C4') SSEPs monitoring in the cortex. Chi-square and Fisher's exact tests were used to analyze the influence of age, spinal deformity classification, and Cobb angle on waveform differentiation and the success rate of SSEPs monitoring. Univariate analysis revealed that age, type of scoliosis, and Cobb angle exerted significant effects on the success rate of intraoperative SSEPs monitoring, and the SSEPs waveform differentiation rate was poorest among patients with congenital scoliosis. Intraoperative monitoring results indicated that the success rate of single-channel SSEPs monitoring was 90.9%, while that of multi-channel monitoring was 98.9% (P < 0.05). Among the intraoperative alarm cases, the incidence of adverse events after single-channel SSEPs monitoring was 66.7%, while the incidence of adverse events after multi-channel SSEPs monitoring was only 28.6%. Multi-channel cortical SSEPs monitoring can effectively and accurately evaluate the function of the posterior column of the spinal cord. Use of multi-channel SSEP monitoring may help to improve the success rate of monitoring and reduce the incidence of postoperative adverse events in patients with congenital scoliosis.

Clinical Trial for the Safety and Feasibility of Pedicle Screws Coated with a Fibroblast Growth Factor-2-Apatite Composite Layer for Posterior Cervical Fusion Surgery.

To solve the instrument loosening problem, we developed a fibroblast growth factor-2-calcium phosphate composite layer as a novel coating material to improve screw fixation strength. The primary aim of the present study was to demonstrate the safety and feasibility of screws coated with the FGF-2-calcium phosphate composite layer for posterior instrumented surgery of the cervical spine. The trial design was a single-arm, open-label, safety and feasibility study. Patients receiving fusion of the cervical spine from C2 (or C3) to C7 (or T1) were recruited. The primary endpoint to confirm safety was any screw-related adverse events. Seven patients who underwent posterior fusion surgery of the cervical spine were enrolled in the present study. The coated pedicle screws were inserted bilaterally into the lowest instrumented vertebrae. There was only one severe adverse event unrelated with the coated screw. Three out of the fourteen coated screws showed loosening. The present results prove the safety and feasibility of pedicle screws coated with the FGF-2-calcium phosphate composite layer for fusion surgery in the cervical spine. This is the first step to apply this novel surface coating in the field of spine surgery.

Single Posterior Surgery Versus Combined Posterior–Anterior Surgery for Lumbar Tuberculosis Patients

Posterior approach of debridement, interbody graft, and instrumentation, and combined posterior-anterior approach of posterior instrumentation and anterior debridement and interbody graft are two essential surgeries for the surgical treatment of spinal tuberculosis (TB), and, until now, which one should be chosen is still controversial. This study aimed to compare the therapeutic efficacy between the single posterior surgery and combined posterior-anterior surgery for lumbar tuberculosis (LTB) patients to elucidate the role of debridement and the effects that result from posterior structure resection. One hundred and nineteen LTB patients managed with single posterior debridement, interbody graft, and instrumentation surgery (Group P, 73 cases), or combined posterior-anterior surgery of posterior instrumentation and anterior debridement and interbody graft (Group P-A, 46 cases) from January 2008 to December 2016 were retrospectively analyzed. Different indexes were compared between the two groups to evaluate the curative effect and explore the role of debridement and the effects that result from posterior structure resection: operation time, blood loss, visual analog scale (VAS), Japanese Orthopaedic Association (JOA), Erythrocyte Sedimentation Rate (ESR), C-reactive Protein (CRP), surgical complication type and rate, spinopelvic sagittal parameters (local kyphosis [LK], pelvic incidence [PI] and pelvic tilt [PT], lumbar lordosis [LL], and sacral slope [SS]), drainage retention duration, hospital stay, time of abscess disappearance, time of activity recovery, and time of bone graft fusion by t-test or χ2 test. The follow-up period ranged from 24 to 60months. No significant variations were detected between the two groups for age, sex ratio, BMI, disease duration, indication, and the preoperative values of VAS, JOA, ESR, CRP, and LK (p > 0.05). The VAS, JOA, ESR, and CRP significantly improved in both groups after the operation (p < 0.05), along with the LK and LL (p < 0.05). Meanwhile, the SS, PI, and PT showed minor improvement after the operation (p > 0.05). Compared to the P-A group, the P group had shorter operation time and less blood loss and hospital stay (p < 0.05). However, both groups presented similar VAS, JOA, ESR, CRP, and LK improvements (p > 0.05). Additionally, the surgical complication type and rate, postoperative spinopelvic sagittal parameters, and bone graft fusion time did not differ between the two groups (p > 0.05). On the other hand, the patients in the P-A group had a shorter time of abscess disappearance and activity recovery (p < 0.05) but a similar time of drainage retention (p > 0.05) compared to the P group. Both single posterior and combined posterior-anterior surgeries presented a good therapeutic effect for LTB patients with a low surgical complication rate and good quality of LK correction and LL reconstruction and maintenance. Moreover, single posterior surgery was less traumatic than combined posterior-anterior surgery but with slower TB lesion healing and activity recovery. Compared to debridement, stability seems to be more vital for STB healing, posterior structure resection does not affect the effect of spinopelvic realignment.

The Degree of Correction Correlation with Clinical Outcomes in Adult Scoliosis Patients after Posterior Instrumentation Surgery

Introduction: Restoring sagittal and coronal parameters is a primary concern in adult scoliosis surgery, yet it remains challenging due to the matured bony structure. This study aims to analyze the relationship between clinical outcomes and the degree of correction achieved through posterior instrumentation surgery in adult scoliosis. Materials and Methods: This study evaluated the clinical and radiological results of 27 adult scoliosis patients who underwent posterior instrumentation, decompression, and correction surgery. Preoperative and follow-up X-rays were performed to assess Cobb angle, sagittal balance, and coronal balance. Visual Analog Score (VAS) and Oswestry Disability Index (ODI) were evaluated preoperatively and at follow-up. Results: The study comprised 27 patients (18 female, 9 male) with a mean age of 68.2 years. Preoperative Cobb angle averaged 42.4°, reducing to 5.9° at final follow-up. Sagittal balance decreased from 30.6 mm preoperatively to 9.7 mm at final follow-up. Coronal balance improved from 22.3 mm preoperatively to 10.5 mm at 2-year follow-up. Preoperative Cobb angle showed a strong correlation with preoperative ODI (p=0.028) and postoperative ODI (p=0.014). Preoperative sagittal balance also correlated strongly with pre and postoperative ODI. However, postoperative Cobb angle and sagittal balance did not correlate with postoperative ODI (p&lt;0.05). Conclusion: While restoring sagittal and coronal parameters is a primary concern in adult scoliosis surgery, the degree of correction achieved does not necessarily correlate with clinical outcomes. Surgeons should consider this when planning surgery, and patients should be informed accordingly.

The Effect of Local Administration of Vancomycin Suspended in Fibrin Glue for Prevention of Surgical Site Infection After Spinal Instrumentation: Comparison by Probability of Treatment Weighting Model.

A retrospective cohort study. To compare the surgical site infection (SSI) rate in patients undergoing spinal instrumentation surgery who received vancomycin suspended in fibrin glue at the surgical site and those who did not. The intrawound application of vancomycin powder for preventing SSI after spinal surgery remains controversial. Vancomycin suspended in fibrin glue is another option for local administration that may be effective. The present study assessed whether vancomycin suspended in fibrin glue could prevent SSI after spinal instrumentation surgery. We enrolled patients who underwent posterior spinal instrumentation surgery with or without fusion for degenerative conditions, spinal trauma, or tumor. A multiple logistic regression model with inverse probability of treatment weighting based on propensity score was used to assess the efficacy of vancomycin suspended in fibrin glue and to account for confounding. A secondary multivariate logistic regression analysis was performed to identify the risk factors associated with SSI. Of the 264 patients enrolled in this study, 134 underwent application of vancomycin suspended in fibrin glue at the surgical site and 130 did not. The incidence of SSI was lower in patients who were treated with vancomycin suspended in fibrin glue (2.2% vs. 8.5%) even after inverse probability of treatment weighting adjustment (adjusted odds ratio: 0.25; 95% CI, 0.0768-0.91; P =0.03). Multivariate logistic regression analysis showed that the treatment with vancomycin suspended in fibrin glue was significantly associated with a lower odds of SSI (odds ratio: 0.2; 95% CI, 0.05-0.85; P =0.03). The administration of vancomycin suspended in fibrin glue was significantly associated with a lower likelihood of SSI in patients undergoing spinal instrumentation surgery.

Isolated Posterior Instrumentation for Selected Cases of Thoracic and Lumbar Spinal Tuberculosis without Radical Debridement.

The purpose of this study was to evaluate the clinical outcomes of thoracic and lumbar spinal tuberculosis treated with isolated posterior instrumentation without radical debridement. This study retrospectively analyzed 73 patients with thoracic and lumbar spinal tuberculosis who were treated using isolated posterior instrumentation without radical debridement in our hospital between January 2012 to December 2019. The patient group was composed of 42 men and 31 women with a mean age of 67.3±8.6 years. The tuberculosis spine instability score (TSIS) was used to evaluate spine stability. All patients received chemotherapy for 18 months after surgery. The time of surgery, blood loss, visual analogue score (VAS), kyphosis angle, Oswestry disability index (ODI), erythrocyte sedimentation rate (ESR), Frankel grading, SF-36 scores, and local recurrence and complications were analyzed to evaluate the efficacy of isolated posterior instrumentation surgery in the treatment of thoracic and lumbar spinal tuberculosis. All patients were followed up for 12 to 24 months (mean 14±3.2 months). The mean surgical time was 1.2±1.4h (range, 1.2-1.6h), and mean blood loss was 107±18mL. The postoperative symptoms were obviously relieved. The VAS, kyphosis angle, DI, and ESR decreased, respectively, from 8.24±1.32, 19.82±3.42, 46.25±3.62, and 49.64±17.61 to 1.12±0.21, 7.14±0.81, 20.17±5.11, and 0.35±1.13 at final follow-up. In comparison to preoperative values, SF-36 scores were significantly improved at final follow-up and the differences were statistically significant (p<0.05). All patients achieved neurological recovery at the final follow-up. There were no recurrences or complications in any of the patients. Isolated posterior instrumentation without radical debridement is a suitable minor surgical trauma that offers a remarkable advantage of effective pain relief, improvement in neurological function and performance status, and no local recurrence for selected patients with thoracic and lumbar spinal tuberculosis.

Serum Procalcitonin Levels in Postoperative Monitoring of Diabetic Patients with Posterior Lumber Vertebral Stabilization Surgery: A Prospective Comparative Study

Objective:To compare the serum procalcitonin levels and other infection markers released in response to the inflammatory response that develops secondary to the operation in patients with or without type 2 diabetes mellitus who underwent spinal instrumentation.Methods:Fifty patients, who belonged to the American Society of Anesthesiologist I-II, were between 18 and 65 years of age, and who had planned for posterior spinal instrumentation surgery were grouped into 2 as group I (n = 25) type 2 diabetic patients (group DM) and group II (n = 25) non-diabetic patients (group non-DM). On the operation day, preoperatively (T0), 5 minutes after intraoperative instrument placement (T1), on postoperative 24th hour (T2), 48th hour (T3), 3rd day (T4), 5th day (T5), 7th day (T6), 10th day (T7), and 15th day (T8), serum samples were obtained from the patients for the evaluation of procalcitonin, C-reactive protein, erythrocyte sedimentation rate, and neutrophil values.Results:Procalcitonin levels were higher in the diabetic patient group at all time points (P < .01); C-reactive protein levels were higher in T1, T2, and T5 in the diabetic patient group (P < .05). There was no difference in erythrocyte sedimentation rate or neutrophil counts between the groups (P > .05). When the alterations in procalcitonin levels were compared between diabetic and non-diabetic groups, in diabetic patients, there were significantly higher increases in the first 6 timelines (P < .05).Conclusion:In diabetic patients, the procalcitonin levels were significantly higher at all time points, predicting an augmented bacterial infection in those patients compared with the non-diabetic patients.

Postoperative progression of ligamentum flavum ossification after posterior instrumented surgery for thoracic posterior longitudinal ligament ossification: long-term outcomes during a minimum 10-year follow-up.

The authors sought to investigate clinical and radiological outcomes after thoracic posterior fusion surgery during a minimum of 10 years of follow-up, including postoperative progression of ossification, in patients with thoracic ossification of the posterior longitudinal ligament (T-OPLL). The study participants were 34 consecutive patients (15 men, 19 women) with an average age at surgery of 53.6 years (range 36-80 years) who underwent posterior decompression and fusion surgery with instrumentation at the authors' hospital. The minimum follow-up period was 10 years. Estimated blood loss, operative time, pre- and postoperative Japanese Orthopaedic Association (JOA) scores, and JOA score recovery rates were investigated. Dekyphotic changes were evaluated on plain radiographs of thoracic kyphotic angles and fusion levels pre- and postoperatively and 10 years after surgery. The distal junctional angle (DJA) was measured preoperatively and at 10 years after surgery to evaluate distal junctional kyphosis (DJK). Ossification progression at distal intervertebrae was investigated on CT. The Cobb angles at T1-12 were 46.8°, 38.7°, and 42.6°, and those at the fusion level were 39.6°, 31.1°, and 34.1° pre- and postoperatively and at 10 years after surgery, respectively. The changes in the kyphotic angles from pre- to postoperatively and to 10 years after surgery were 8.0° and 7.2° at T1-12 and 8.4° and 7.9° at the fusion level, respectively. The DJA changed from 4.5° postoperatively to 10.9° at 10 years after surgery. There were 11 patients (32.3%) with DJK during follow-up, including 4 (11.8%) with vertebral compression fractures at lower instrumented vertebrae or adjacent vertebrae. Progression of ossification of the ligamentum flavum (OLF) on the caudal side occurred in 8 cases (23.6%), but none had ossification of the posterior longitudinal ligament (OPLL) progression. Cases with OLF progression had a significantly lower rate of DJK (0% vs 38.5%, p < 0.01), a lower DJA (3.4° vs 13.2°, p < 0.01), and a smaller change in DJA at 10 years after surgery (0.8° vs 8.1°, p < 0.01). Posterior decompression and fusion surgery with instrumentation for T-OPLL was found to be a relatively safe and stable surgical procedure based on the long-term outcomes. Progression of OLF on the caudal side occurred in 23.6% of cases, but cases with OLF progression did not have DJK. Progression of DJK shifts the load in the spinal canal forward and the load on the ligamentum flavum is decreased. This may explain the lack of ossification in cases with DJK.

Halo traction combined with posterior-only approach correction for cervical kyphosis with Neurofibromatosis-1: minimum 2\u2009years follow-up

BackgroundSurgical management of cervical kyphosis in patients with NF-1 is a challenging task. Presently, anterior-only (AO), posterior-only (PO) and combined anterior-posterior (AP) spinal fusion are common surgical strategies. However, the choice of surgical strategy and application of Halo traction remain controversial. Few studies have shown and recommended posterior-only approach for cervical kyphosis correction in patients with NF-1. The aim of this study is to evaluate the safety and the effectiveness of halo Traction combined with posterior-only approach correction for treatment of cervical kyphosis with NF-1.MethodsTwenty-six patients with severe cervical kyphosis due to NF-1 were reviewed retrospectively between January 2010 and April 2018. All the cases underwent halo traction combined with posterior instrumentation and fusion surgery. Correction result, neurologic status and complications were analyzed.ResultsIn this study, cervical kyphosis Cobb angle decreased from initial 61.3 ± 19.7 degrees to postoperative 10.6 ± 3.7 degrees (P<0.01), with total correction rate of 82.7%, which consist of 45.8% from halo traction and 36.9% from surgical correction. JOA scores were improved from preoperative 13.3 ± 1.6 to postoperative 16.2 ± 0.7 (P<0.01). Neurological status was also improved. There was no correction loss and the neurological status was stable in mean 43 months follow-up. Three patients experienced minor complications and one patient underwent a second surgery.ConclusionHalo traction combined with PO approach surgery is safe and effective method for cervical kyphosis correction in patients with NF-1. A satisfied correction result, and successful bone fusion can be achieved via this procedure, even improvement of neurological deficits can also be obtained. Our study suggested that halo traction combined with PO approach surgery is another consideration for cervical kyphosis correction in patients with NF-1.

Impact of liberal intraoperative allogeneic blood transfusion on postoperative morbidity and mortality in major thoracic and lumbar posterior spine instrumentation surgeries.

To investigate the impact of intraoperative blood transfusion on outcomes in patients who had major thoracic and lumber posterior spine instrumentation surgery. Retrospective study included patients who underwent major spine surgery between 2013 and 2017. Patients' demographics, surgical charts, anesthesia charts, discharge charts and follow-up outpatient charts were reviewed. Data collection included: age, gender, BMI, Charlson Co-morbidity Index (CCI) scores, American Society of Anesthesiologists (ASA) scores, amount of estimated blood loss [% estimated blood volume (%EBV)], amount of blood transfused during surgery and post-surgery before discharge, number of fusion levels, pre- and postoperative hemoglobin (Hb) levels, and length of hospital stay. Also collected in-hospital postoperative complications (cardiovascular, pulmonary, infections and deaths). Patients' postoperative intubation status data documented. Reviewed follow-up charts to document any complications. Sample size = 289; No transfusion = 92; transfusion = 197. Transfused patients were significantly older, p < 0.001, higher average BMIs (p < 0.001); ASA scores (p < 0.001); CCI scores (p < 0.001), mean postoperative Hb level (p = 0.004), average intraoperative %EBV loss (p < 0.001), longer hospital stays (p = 0.003). Non-transfusion cohort had significantly higher proportion of patients (p < 0.001) extubated immediately after surgery. Seventeen patients had at least one in-hospital complication, p = 0.05. Complications were not significant among groups. Intraoperative blood transfusions and high volume intraoperative allogeneic blood transfusions did not increase risk for in-hospital complications or surgical site infections. Delayed extubations noticed in patients who received higher volumes of intraoperative allogeneic blood transfusions. High-volume intraoperative blood transfusions increased length of hospital stays. High post-hospital surgical infections associated with high volume intraoperative blood transfusions. Results should be interpreted cautiously due to small sample size.

The Relationship between Adjacent Segment Pathology and Facet Joint Violation by Pedicle Screw after Posterior Lumbar Instrumentation Surgery.

Transpedicular screw instrumentation systems have been increasingly utilized during the fusion of lumbar spine procedures. The superior segment facet joint violation of the pedicle screw is thought to have potential for accelerating symptomatic adjacent-segment pathology (ASP). The purpose of this study was to investigate the relationship between the superior segment facet joint violation by transpedicular screws and the development of ASP. Among all patients who underwent operations involving one- or two-level posterior lumbar arthrodesis at the Chonnam National University Hospital from 1992 to 2012, 87 patients were selected for this study. Fifty-six patients were included in the ASP group, and 31 were included in the non-ASP group. We used lumbar three-dimensional computed tomography (CT) to assess the violation of the superior facet joint by a transpedicular screw. The assessment is presented in scores ranging from zero to two, with zero indicating no violation (type I); one point indicating suspected violation (type II); and two points indicating definitely facet joint violation (type III). Facet violation was reported in 31 patients in the ASP group (n = 56), and in 13 patients in the non-ASP group (n = 31). The types of facet joint violation according to our scoring system were as follows: type I, 59 screws (52.7%); type II, 26 screws (23.2%); and type III, 27 screws (24.1%) in the ASP group; and type I, 43 screws (69.4%), type II, 14 screws (22.6 %); and type III, 5 screws (8.0%) in the non-ASP group. The score of facet joint violation in each patient according to our scoring system were as follows: 0 points, 25 patients (44.6%); 1 point, 8 patients (14.3%); 2 points, 4 patients (7.1%); 3 points, 11 patients (19.7%); 4 points, 8 patients (14.3%) in the ASP group; and 0 points, 18 patients (58.1%); 1 point, 4 patients (12.9%); 2 points, 7 patients (22.6%); 3 points, 2 patients (6.4%); 4 points, 0 patients (0%) in the non-ASP group. The mean scores were 1.4 points in the ASP group and 0.8 points in the non-ASP group (p < 0.05). We conclude that the position of the pedicle screw farther away from the facet joint surface can reduce the degeneration of the superior adjacent segment. Therefore, close attention to the screw position during surgery may reduce the rate of superior adjacent-segment pathologies.

Minimally Invasive Spine Surgery versus Open Posterior Instrumentation Surgery for Unstable Thoracolumbar Burst Fracture.

Study DesignRetrospective study.PurposeTo compare the clinical and radiological results of minimally invasive spine surgery (MISS) and open posterior instrumentation surgery for the treatment of unstable burst fractures.Overview of LiteratureMISS has exhibited postoperative outcomes similar to those obtained using open posterior instrumentation in various spine diseases. There remains no consensus regarding the use of MISS in the treatment of unstable burst fracture.MethodsWe enrolled 40 patients who underwent either MISS (M group, 20 patients) or open posterior instrumentation surgery (O group, 20 patients) for the treatment of traumatic unstable burst fractures. Clinical outcomes were evaluated based on postoperative back pain, operation time, blood loss, hospital stay duration, and perioperative complications. For radiologic evaluation, preoperative magnetic resonance imaging and plain radiography were performed before and after the surgery to evaluate the changes in the kyphotic angle and fracture union.ResultsThe change in the kyphotic angle was −8.2°±5.8° in the M group and −8.0°±7.8° in the O group. No significant difference was noted in terms of the change in the kyphotic angle (p=0.94, t-test) after 12 months of surgery. The Visual Analog Scale score was 1.5±0.7 points in the M group, while it was 5.2±1.4 points in the O group. In the M group, back pain has significantly decreased (p<0.01, t-test). The estimated blood loss was 195.5 mL in the M group and 1,077.5 mL in the O group; the operation time was significantly decreased in the O group from 290.7 to 120.7 minutes in the M group (p<0.05, t-test) (p=0.36, t-test). The average duration of hospital stay was 36.0 days in the M group and 41.9 days in the O group (p=0.36, t-test).ConclusionsFor the treatment of unstable burst fractures, MISS showed significant differences in terms of postoperative back pain, operation time, and blood loss as compared to open posterior instrumentation surgery.

Radiographic and clinical evidence: osteoarthritic knee can change surgical result for lumbar degenerative disease patient undergone surgery for 3-year follow-up: a retrospective comparative clinical study

BackgroundThere is a paucity of reports clarifying the implication of knee osteoarthritis (OA) on spinal sagittal alignment of patients undergone surgery for lumbar spine. This study aimed to analyze how osteoarthritic knee affects radiographic and clinical results of degenerative lumbar disease patients undergone lumbar fusion.MethodsWe retrospectively reviewed the medical records and radiographs of 74 consecutive degenerative lumbar disease patients who underwent posterior instrumentation and fusion surgery between May 2016 and June 2017 and were followed up for minimum 3 years postoperatively. The patients were divided into 2 groups according to the severity of knee OA by Kellgren-Lawrence grading (KLG) scale (group I, KLG 1 or 2 [n = 39]; group II, KLG 3 or 4 [n = 35]). Patient demographic data, comorbidities, spinal sagittal parameters and clinical scores were extracted and compared at preoperative, postoperative 1 month and the ultimate follow-up between the groups. In radiographic assessment, sagittal alignment parameters and sagittal balance were used. In clinical assessment, the scores of Oswestry disability index (ODI) and Scoliosis Research Society questionnaire (SRS-22) were used. For the frequency analysis of categorical variables across the groups, chi-square test was used and student t tests was used to compare the differences of continuous variables.ResultsIn radiographic assessment, TLK (thoracolumbar kyphosis), LL (lumbar lordosis), PT (pelvic tilt), C7 SVA (sagittal vertical axis) in both groups improved significantly after surgery (p < 0.05). However, LL, PT, C7SVA improved at postoperative 1 month in the group II were not maintained at the ultimate postoperative follow-up. In clinical assessment, preoperative Oswestry disability index (ODI, %) and all SRS-22 subscores of the group I and II were not different (p > 0.05). There were significant differences between the groups at the ultimate follow-up in ODI (− 25.6 vs − 12.1, p < 0.001), SRS total score (%) (28 vs 20, p = 0.037), function subscore (1.4 vs 0.7, p = 0.016), and satisfaction subscore (1.6 vs 0.6, p < 0.001).ConclusionOsteoarthritic knee with KLG 3 or 4 have a negative influence on maintaining postoperative spinal sagittal alignment, balance, and the clinical outcomes achieved immediately by posterior instrumentation and fusion for lumbar degenerative disease.Trial registrationThis study was retrospectively registered with approval by the institutional review board (IRB) of our institution (approval number: 2018–11-007).

CORRELATION BETWEEN THE SCHANZ SCREW INSERTION ANGLE AND THE LOSS OF KYPHOSIS CORRECTION IN THORACOLUMBAR FRACTURES

ABSTRACT Objective To compare the Schanz screw insertion angle and the loss of the regional kyphosis correction in thoracolumbar burst fractures following posterior short instrumentation surgery. Methods Patients with a thoracolumbar burst fracture between levels T11-L2 were divided into two groups (parallel and divergent) according to the angle formed between the Schanz screw and the vertebral plateau. Regional kyphosis was evaluated in preoperative, immediate postoperative and last follow-up radiographs. Results Of the 58 patients evaluated, 31 had a parallel assembly and 27 had a divergent assembly. When we analyzed the angle of kyphosis, no statistical difference was observed between the pre- and postoperative radiographs. However, a statistical difference in the last follow-up radiographs and in the final loss of the kyphosis correction was confirmed. Conclusion The insertion of Schanz screws with a divergent assembly presents better radiographic results with less loss of kyphosis correction angle when compared with the parallel assembly technique. Level of Evidence III; Retrospective cohort study.

Delayed surgical site infection after posterior cervical instrumented surgery in a patient with atopic dermatitis: a case report.

Objective: Atopic dermatitis (AD) is one of the known risk factors for Staphylococcus aureus infection. The authors report the case of a patient with cervical spondylosis and AD who developed delayed surgical site infection after posterior cervical instrumented surgery.Patient: A 39-year-old male presented to our hospital with paralysis of the left upper extremity without any cause or prior injury. He had a history of severe AD. We performed C3–C7 posterior decompression and instrumented fusion based on the diagnosis of cervical spondylotic amyotrophy. One year after surgery, his deltoid and bicep muscle strength were fully recovered. Nevertheless, his neck pain worsened 2 years after surgery following worsening of AD. One month after that, he developed severe myelopathy and was admitted to our hospital. Radiographic findings showed that all the screws had loosened and the retropharyngeal space had expanded. Magnetic resonance imaging and computed tomography showed severe abscess formation and destruction of the C7/T1 vertebrae.Result: We diagnosed him with delayed surgical site infection. Methicillin-resistant Staphylococcus aureus was identified on abscess culture. The patient responded adequately to treatment with antibiotic therapy and two debridements and the infection subsided.Conclusion: We should consider the possibility of delayed surgical site infection when conducting instrumented spinal surgery in patients with severe AD.

Connection of discontinuous segments in early functional recovery from thoracic ossification of the posterior longitudinal ligament treated with posterior instrumented surgery.

The objective of this study was to investigate the relationship between morphological changes in thoracic ossification of the posterior longitudinal ligament (T-OPLL) and postoperative neurological recovery after thoracic posterior fusion surgery. Changes of OPLL morphology and postoperative recovery in cases with T-OPLL have not been examined. In this prospective study, the authors evaluated data from 44 patients (23 male and 21 female) who underwent posterior decompression and fusion surgery with instrumentation for the treatment of T-OPLL at our hospital. The patients' mean age at surgery was 50.7 years (range 38-68 years). The minimum duration of follow-up was 2 years. The location of thoracic ossification of the ligamentum flavum (T-OLF), T-OLF at the OPLL level, OPLL morphology, fusion range, estimated blood loss, operative time, pre- and postoperative Japanese Orthopaedic Association (JOA) scores, and JOA recovery rate were investigated. Reconstructed sagittal multislice CT images were obtained before and at 3 and 6 months and 1 and 2 years after surgery. The basic fusion area was 3 vertebrae above and below the OPLL lesion. All parameters were compared between patients with and without continuity across the disc space at the OPLL at 3 and 6 months after surgery. The preoperative morphology of OPLL was discontinuous across the disc space between the rostral and caudal ossification regions on sagittal CT images in all but one of the patients. Postoperatively, these segments became continuous in 42 patients (97.7%; occurring by 6.6 months on average) without progression of OPLL thickness. Patients with continuity at 3 months had significantly lower rates of diabetes mellitus (p < 0.05) and motor palsy in the lower extremities (p < 0.01). The group with continuity also had significantly higher mean postoperative JOA scores at 3 (p < 0.01) and 6 (p < 0.05) months and mean JOA recovery rates at 3 and 6 months (both p < 0.01) after surgery. Preoperatively, discontinuity of rostral and caudal ossified lesions was found on CT in all patients but one of this group of 44 patients who needed surgery for T-OPLL. Rigid fixation with instrumentation may have allowed these segments to connect at the OPLL. Such OPLL continuity at an early stage after surgery may accelerate spinal cord recovery.