Posterior Spinal Fixation Research Articles

Applications of Carbon Fiber Instrumentation in Spinal Oncology: Recent Innovations in Spinal Instrumentation and 2-Dimensional Illustrative Operative Video.

The management of spinal oncology necessitates a multimodal approach, with surgical intervention, radiation-based therapy, and postoperative advanced imaging. These systems must work well together to provide optimal patient outcomes. Traditional metallic spinal implants produce image artifacts and lead to radiation dose attenuation, which inhibit both disease monitoring and disease treatment, respectively. To demonstrate the feasibility of an improved biomaterial implant that provides structural stability, while also allowing for disease monitoring and treatment in spinal oncology patients. From February 2021 to September 2021, 3 patients with spinal oncologic deformity requiring resection and posterior spinal stabilization underwent fixation with polyether ether ketone-carbon fiber implants at a single academic institution. Patient ages ranged from 23 to 74 years (mean: 44.7 years). All patients underwent posterior spinal fixation using standard approaches. They each received polyether ether ketone-carbon fiber pedicle screw and rod implants, placed in standard fashion. There were no dural tears, postoperative wound infections, or other complications related to their treatment. Postoperative surveillance revealed gross total resection of the targeted tumor on postoperative radiographic imaging. Polyether ether ketone-carbon fiber implants are a safe and effective option for the treatment of thoracolumbar posterior spinal pathology. The utilization of this novel type of instrumentation in posterior spinal approaches may provide benefit to patients with spinal tumors over existing forms of posterior spinal instrumentation.

Chondroblastoma of Thoracic Vertebrae: a Case Report and Review of the Literature.

Chondroblastoma is a rare benign cartilaginous bone tumor typically seen at the epiphysis of long axial bones. In this regard, there are rare findings about spinal chondroblastomas. We report a 29-year-old man with T1 vertebral chondroblastoma misdiagnosed with a traumatic fracture following an accident. The patient was admitted to our clinic with a chief complaint of axial back pain and kyphosis following posterior spinal fixation. We report his clinical and imaging data before his past operation and at this admission. Our patient underwent a two-stage operation. In the first stage, posterior spinal reconstruction and kyphosis correction was performed. In the second stage, mass resection was performed anteriorly in the T1 vertebral body as much as possible. The results confirmed the chondroblastoma diagnosis histologically. Our patient remained symptom-free with no growth in tumor remnant during 6months follow-up. Although vertebral chondroblastoma is a sporadic tumor, it should be considered in the differential diagnosis when facing a vertebral infiltrative osteolytic mass, even when mimicking a traumatic fracture after the accident. In addition, histological confirmation is necessary under such conditions. We also reviewed the literature's clinical presentations, imaging findings, and treatments of 34 case reports with vertebral chondroblastoma.

Global stiffness and residual stresses in spinal fixator systems: A validated finite element study on the interconnection mechanism

Posterior spinal fixation systems are the gold standard to treat different column disorders using rods and screws. The proper connection between them is guaranteed by the Interconnection Mechanism (IM), consisting of different metallic subcomponents held together through the application of tightening torque. The response of the fixation system is defined by its overall stiffness, which in turn is governed by the local residual stress field arising during tightening. Although literature computational models for studying spinal fixation are becoming increasingly anatomically complex, most studies disregard completely the realistic modeling of the IM, namely choosing elastic-plastic material models and proper contact interactions. In this frame, the present study aims at increasing awareness in the field of spinal fixation modeling by investigating the mechanical response of the IM in terms of overall stiffness and local residual stresses. Once validated through dedicated experiments, the results of the proposed model have been compared with the current literature, highlighting the key role of the IM in the reliable modeling of spinal fixation.

Influence of spinal lordosis correction location on proximal junctional failure: a biomechanical study.

Assessment of sagittal lordosis distribution on mechanical proximal junctional failure-related risks through computer-based biomechanical models. To biomechanically assess how lordosis distribution influences radiographical and biomechanical indices related to Proximal Junctional Failure (PJF). The "optimal" patient-specific targets to restore the sagittal balance in posterior spinal fusion are still not known. Among these, the effect of the lumbar lordosis correction strategy on complications such as PJF remain uncertain. In this computational biomechanical study, five adult spinal deformity patients who underwent posterior spinal fixation were retrospectively reviewed. Their surgery, first erect posture and flexion movement were simulated with a patient-specific multibody model. Three pedicle subtraction osteotomy (PSO) levels (L3, L4, and L5) were simulated, with consistent global lordosis for a given patient and pelvic tilt adjusted accordingly to the actual surgery. Computed loads on the anterior spine and instrumentation were analyzed and compared using Kruskal-Wallis statistical tests and Spearman correlations. In these models, no significant correlations were found between the lordosis distribution index (LDI), PSO level and biomechanical PJF-related indices. However, increasing the sagittal vertical axis (SVA) and thoracolumbar junction angle (TLJ) and decreasing the sacral slope (SS) increased the bending moment sustained by the rods at the proximal instrumented level (r = 0.52, 0.57, -0.56, respectively, p < 0.05). There was a negative correlation between SS and the bending moment held by the adjacent proximal segment (r = -0.71, p < 0.05). Based on these biomechanical simulations, there was no correlation between the lordosis distribution and PJF-associated biomechanical factors. However, increasing SS and flattening the TLJ, as postural adjustment strategies required by a more distal PSO, did decrease such PJF-related factors. Sagittal restoration and PJF risks remain multifactorial, and the use of patient-specific biomechanical models may help to better understand the complex interrelated mechanisms.

Radiological outcome of operative treatment with posterior approach in patients with thoracolumbar junction traumatic injuries: A single-center pilot study in a developing country.

Background: The thoracolumbar junction (TLJ) represents a transition zone of the spine that leads to a high incidence of fractures. The treatment of burst fractures remains controversial regarding the ideal management. This study assessed the postoperative radiological outcome of TLJ fixation in patients with TLJ injuries who underwent surgery.Methods: All traumatic patients with TLJ injuries who were referred to the Khatam hospital of Zahedan between 2015 and 2020, with their thoracolumbar injury classification and severity score (TLICS) of four or more and who underwent surgery, were included in this study. The patients who entered the study were called for a follow-up examination. The degree of kyphosis, proximal junctional kyphosis, and fusion were assessed in these patients.Results: Among 273 patients, the average age was 43.5 ± 12.3 (21–73) years. One hundred and ninety-eight patients (72.5%) had no neurological symptoms at admission. Based on the above criteria, the kyphosis angle of these patients was calculated before surgery, which in 46 patients (16.8%), the kyphosis angle was more than 25°. Preoperation kyphosis was significantly associated with follow-up kyphosis (P < 0.001). Evidence of no fusion was also observed in 22 patients (8.1%). According to the Chi-square test, no association was observed between preoperative kyphosis and postoperative complications, including PJK and fusion (P > 0.05).Conclusion: According to our study, the posterior spinal fixation procedure is a low-complication method with an acceptable radiological outcome. Although kyphosis before surgery is a factor in developing long-term kyphosis, it is not associated with nonfusion and PJK.

Seat belt syndrome is caused by a different mechanism: A case report

Introduction and importanceSeat belt syndrome is associated with multiple visceral injuries and vertebral burst fractures. Small Intestinal perforations are seen in 5–15 % of blunt abdominal trauma. In our case, we will report a case that presented small intestinal perforation and thoracic vertebral fracture caused by a different mechanism.Case presentationPreviously healthy 48-year-old male presented to the emergency department following falling from 15 feats height. He was a paraplegic with a sensory level at T12. He did not have a clinical feature of spinal shock. He was complaining of epigastric and central abdominal pain and tenderness and was diagnosed to have a proximal Jejunal perforation associated with an unstable fracture of T12 causing spinal compression. Open intestinal repair followed by a posterior spinal exploration and pedicle screw fixation done.Clinical discussionViolent injury due to different mechanisms can have similar injuries to Seat belt syndrome. Ultrasonography is used to detect pneumoperitoneum, but the Contrast study is the gold standard to detect visceral injuries. The surgical approach to visceral injury depends on the patient's condition. But the laparoscopic approach has a more favorable postoperative outcome than open access.ConclusionIntestinal perforations associated with the neurological deficit are difficult to identify in an initial clinical assessment. Thoracolumbar fractures can associate with small bowel injuries during high-velocity trauma. Early identification and repair of the intestinal injury are important to prevent devastating complications and to improve neurological recovery after spinal surgery.

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.

Sacral-Alar-Iliac (SAI) Fixation in Children With Spine Deformity: Minimum 10-Year Follow-Up.

Sacral-alar-iliac (SAI) screws are utilized to achieve pelvic fixation in spine deformity patients. The primary purpose of this study is to investigate the long-term outcomes of pediatric patients with scoliosis treated with posterior spinal fusion and SAI fixation at 10-year clinical and radiographic follow-up. We reviewed the clinical and radiographic records of patients aged 18 years or below treated for scoliosis with posterior spinal fusion using SAI fixation. Pelvic obliquity and the major coronal curve were determined at the preoperative visit and 6-week, 1-year, 5-year, and 10-year postoperative visits. SAI screw-specific data collected included screw dimensions, rate of screw revision, pain at the SAI screw sites, presence of lucency >2 mm around the screw, screw loosening or breaking, and deep surgical site infections. Ninety-seven of 151 patients (75%) were included. The average age at index surgery was 13.5±3.1 years, and the most common diagnosis was cerebral palsy (67%). The mean duration of follow-up was 11±3 years. The mean pelvic obliquity measured 20±8.0 degrees preoperatively, and 8.7±4.0 degrees at the 10-year follow-up. There were no significant difference in pelvic obliquity when comparing the 10-year follow-up visit with the 6-week postoperative follow-up. Average screw dimensions were 8.4×68.8 mm. By the 10-year follow-up, 4 patients (4%) had at least 1 SAI screw-related complication. Of these patients, 2 (2%) had pain at 1 SAI screw, 4 (4%) had lucency around the screw, and 3 (3%) had broken or loose screws. Two (2%) required SAI screw revision because of late deep wound infection, and underwent exchange with a longer screw. There were no intrapelvic protrusions, vascular, or neurological complications. SAI screws are a safe and effective method for pelvic fixation in children with spinal deformity. The outcomes at ≥10 years are satisfactory, with low rates of long-term complications and excellent postoperative correction and subsequent maintenance of coronal curvature and pelvic obliquity over time. Level IV.

Unidirectional porous beta-tricalcium phosphate as a potential bone regeneration material for infectious bony cavity without debridement in pyogenic spondylitis.

An 81-year-old man was initially diagnosed with T11 osteoporotic vertebral fracture. The fractured vertebral body was filled with unidirectional porous beta-tricalcium phosphate (β-TCP) granules, and posterior spinal fixation was conducted using percutaneous pedicle screws. However, the pain did not improve, the inflammatory response increased, and bone destructive changes extended to T10. The correct diagnosis was pyogenic spondylitis with concomitant T11 fragility vertebral fracture. Revision surgery was conducted 2weeks after the initial surgery, the T10 and T11 pedicle screws were removed, and refixation was conducted. After the revision surgery, the pain improved and mobilization proceeded. The infection was suppressed by the administration of sensitive antibiotics. One month after surgery, a lateral bone bridge appeared at the T10/11 intervertebral level. This increased in size over time, and synostosis was achieved at 6months. Resorption of the unidirectional porous β-TCP granules was observed over time and partial replacement with autologous bone was evident from 6months after the revision surgery. Two years and 6months after the revision surgery, although there were some residual β-TCP and bony defect in the center of the vertebral body, the bilateral walls have well regenerated. This suggested that given an environment of sensitive antibiotic administration and restricted local instability, unidirectional porous β-TCP implanted into an infected vertebral body may function as a resorbable bone regeneration scaffold without impeding infection control even without debridement of the infected bony cavity.

The role of cross-link augmentation on fusion rate and patient satisfaction among patients with traumatic thoracolumbar spinal fracture: A randomized clinical trial.

Most of the studies evaluating the effect of cross links on spinal stability are performed in vitro on porcine or human spine segments and there is limited data regarding clinical benefits of cross link augmentation in traumatic injuries. In this study we aimed to evaluate the effects of cross-links insertion between rods on the fusion rates and post-surgical patients' satisfaction among patients with traumatic thoracolumbar fractures who underwent posterior spinal fixation with pedicle screws. This study was conducted as a randomized clinical trial on 60 patients suffering from traumatic thoracolumbar vertebrae fractures. Patients were randomized into three groups: A (without any cross-link), B (One cross-link insertion) and C (two cross-links insertion). Six months after surgery outcomes were evaluated: fusion rates (plain X-ray and CT scan), Back pain (Visual Analog Scale) and patient satisfaction (fair, good, excellent). In group A 13 (65%) patients had structured bone fusion, but in 7 (35%) patients bone fusion was not observed. In both groups B and C, 19 patients (95%) had bone fusion, but only in 1 patient (5%) fusion failed (p=0.009). In group A, fair satisfaction has the highest rate (8 patients (40%)) compared to the other groups. The highest reported severity of back pain was observed in group A while the lowest reported intensity of back pain was related to group B (p=0.001). Adding cross link to posterior spinal fixations of patients with traumatic thoracolumbar fractures can be associated with better final fusion results and patients' satisfaction. However it is necessary to design studies with greater sample sizes to confirm this theory. IRCT20120527009878N3.

The role of cross-link augmentation on fusion rate and patient satisfaction among patients with traumatic thoracolumbar spinal fracture: A randomized clinical trial

Introduction and objectivesMost of the studies evaluating the effect of cross links on spinal stability are performed in vitro on porcine or human spine segments and there is limited data regarding clinical benefits of cross link augmentation in traumatic injuries. In this study we aimed to evaluate the effects of cross-links insertion between rods on the fusion rates and post-surgical patients’ satisfaction among patients with traumatic thoracolumbar fractures who underwent posterior spinal fixation with pedicle screws. Materials and methodsThis study was conducted as a randomized clinical trial on 60 patients suffering from traumatic thoracolumbar vertebrae fractures. Patients were randomized into three groups: A (without any cross-link), B (One cross-link insertion) and C (two cross-links insertion). Six months after surgery outcomes were evaluated: fusion rates (plain X-ray and CT scan), Back pain (Visual Analog Scale) and patient satisfaction (fair, good, excellent). ResultsIn group A 13 (65%) patients had structured bone fusion, but in 7 (35%) patients bone fusion was not observed. In both groups B and C, 19 patients (95%) had bone fusion, but only in 1 patient (5%) fusion failed (p=0.009). In group A, fair satisfaction has the highest rate (8 patients (40%)) compared to the other groups. The highest reported severity of back pain was observed in group A while the lowest reported intensity of back pain was related to group B (p=0.001). ConclusionsAdding cross link to posterior spinal fixations of patients with traumatic thoracolumbar fractures can be associated with better final fusion results and patients’ satisfaction. However it is necessary to design studies with greater sample sizes to confirm this theory.Trial registration number: IRCT20120527009878N3.

Study on the clinical efficacy of bone-filled mesh vertebroplasty combined with posterior screw and rod internal fixation in the treatment of thoracolumbar metastases: a retrospective cohort study.

Thoracolumbar metastases is a difficult disease to deal with in spinal surgery. The aim of this study is to investigate the clinical efficacy of bone-filled mesh vertebroplasty combined with posterior spinal internal fixation in the treatment of thoracolumbar metastases. The clinical data of 68 patients with thoracolumbar vertebral metastases from January 2018 to April 2020 were retrospectively analyzed. A total of 37 cases underwent bone filling mesh pocket vertebroplasty combined with posterior spinal internal fixation as the observation group, and 31 cases underwent routine vertebroplasty combined with posterior spinal internal fixation as the control group. The visual analogue scale (VAS) scores, Oswestry disability index (ODI) scores, Karnofsky performance status (KPS) scores, and the heights of the anterior margin and middle of the diseased vertebra were compared between the 2 groups before and 1 week, 3 months, 6 months, and 1 year after surgery. All cases successfully completed the operation, and there was no pulmonary embolism, paraplegia, or perioperative death in follow-up reported. Intraoperative bone cement leakage occurred in 4 cases with a total of 6 vertebrae in the observation group (leakage rate: 14.29%), and in 8 cases with a total of 11 vertebrae in control group (leakage rate: 31.43%). The differences in VAS scores, ODI scores, KPS scores, and the heights of the anterior margin and middle of the diseased vertebra between preoperative and postoperative periods at 1 week, 3 months, 6 months, and 1 year in both groups were statistically significant (P<0.05), while the differences between the 2 groups were not statistically significant (P<0.05). The application of bone-filled mesh vertebroplasty combined with posterior internal pedicle screws fixation for the treatment of thoracolumbar metastases can not only reduce the injury of the operation, but also achieve the purpose of relieving pain, controlling local tumor growth to a certain extent, restoring neural function, and rebuilding the stability of the spine, which has important clinical value.

Commentary: A Novel Mobile-Device-Based Navigation System for Placement of Posterior Spinal Fixation.

Department of Neurosurgery, Henry Ford Hospital, Detroit, Michigan, USA Correspondence: Victor Chang, MD, Department of Neurosurgery, Henry Ford Hospital, 2799 W Grand Blvd, Detroit, MI48202, USA. Email: [email protected]

A Novel Mobile Device-Based Navigation System for Placement of Posterior Spinal Fixation.

Spinal navigation technology has revolutionized the field of spine surgery. However, adoption has not been universal. Reasons include cost, interruption in surgical workflow, increased OR time, and potential implant incompatibility, among others. A technology that maintains performance but alleviates these drawbacks would be valuable. A mobile device-based navigation system has been developed which relies on the iOS platform and the gyroscopic-on-chip technology, therein to guide accurate placement of pedicle screws. This system maintains a minimal footprint and resolves difficulty with line-of-sight interruption and attention shift. To evaluate the accuracy and reliability of this device in a preclinical setting. A cadaver study was performed involving 13 surgeons placing 26 pedicle screws using the novel assistive technology. CT scans were then performed, and accuracy was assessed by designating each screw a Gertzbein-Robbins score. In addition, bench top table testing was performed. This consisted of 360 tests of both the accuracy of the device's pitch and roll, corresponding to the rotation about the device's x-axis and y-axis, respectively. The mean Gertzbein-Robbins score of the 26 screws placed in the cadaver study was 1.29. The mean deviation from centerline pedicle placement was 0.66 mm, with a standard deviation of 1.52 mm. The bench top study results included a mean pitch error of 0.17° + 0.09° and a mean roll error of 0.29 + 0.21. The novel mobile device-based navigation system for placement of pedicle screws presented here demonstrates high levels of accuracy and reliability in the preclinical setting.

Hidden blood loss in extreme lateral interbody fusion for adult spinal deformity

BackgroundExtreme lateral interbody fusion (XLIF) is often used with posterior spinal fixation (PSF) to treat adult spinal deformity (ASD). However, the amount of intraoperative blood loss (IBL) reported for XLIF may underestimate the total blood loss (TBL). The objective of this study was to determine the total perioperative blood loss in XLIF for ASD. MethodsWe assessed 30 consecutive ASD patients with Schwab-SRS type L (mean age: 68.7 ± 8.2 years; mean follow-up 2.0 ± 1.3 years) who were treated by multilevel XLIF (mean, 2.5 ± 0.6 levels) followed by PSF after 3–5 days. We calculated the TBL after XLIF by the Gross equation, by hemoglobin (Hb) balance, and by the Orthopedic Surgery Transfusion Hemoglobin European Overview (OSTHEO) formula. We defined hidden blood loss (HBL) as the difference between the TBL and IBL. Pearson correlation, Spearman correlation, and multiple logistic regression analysis were performed to investigate the risk factors related to HBL. ResultsPost-XLIF blood tests showed a significant decrease in the Hb (from 11.8 ± 1.1 mg/dl to 10.6 ± 1.1 mg/dl) and hematocrit (from 36.0 ± 3.2% to 32.5 ± 3.2%). Although the mean IBL was relatively small (33 ± 52 mL), we calculated the TBL as 291 ± 171 mL (Gross equation) and the HBL as 258 ± 168 mL by Gross equation, which was 8 times greater than the IBL on average. There was no difference in the results obtained using the three methods. Multiple logistic regression analysis indicated preoperative lumber lordosis was the risk factor of high HBL (Odds ratio = 1.085, 95%CI: 1.006–1.170, p = 0.035). ConclusionsThe HBL in XLIF was 8 times greater than the IBL. During the perioperative course of correction and fusion surgery for ASD with XLIF, surgeons need to pay attention not to underestimate the TBL.

Outcome of patients undergoing posterior spine fixation and decompression for posttraumatic thoracolumbar spine fractures and the factors predicting it

Background: Posterior spine fixation and decompression for thoracic and lumbar spine fractures have the advantage of stabilization of the fracture, decompression of neural canal, early mobilization and rehabilitation of the patient. The study aimed to find out the postoperative outcome and complications following posterior spine surgery and the factors affecting the outcome.&#x0D; Methods: A retrospective study was carried out among 44 patients who underwent posterior spine decompression and fusion for thoracic and lumbar spine fracture. The data regarding patient presenting symptoms, comorbidity, associated injuries and imaging finding in CT and MRI were collected. The postoperative outcome of patients after surgery was assessed using ASIA impairment scale, KPS, VAS scale for pain are noted at the preoperative and postoperative period. Other factors like improvement of bowel and bladder symptoms, back stiffness and return to the job after surgery were also found out.&#x0D; Results: There was a significant improvement in ASIA impairment scale (mean =0.74 grade), KPS score (mean = 40) and VAS pain scale (mean = 6.7) at 6 months follow up after surgery. Improvement in ASIA impairment scale was more in the patient with severe canal compromise (mean = 1.62 grade), patients with translational/ distraction injuries (mean= 1.01grade) and patients with paraparesis (mean=1.06). Only one-third of patients with bowel and bladder involvement improved after surgery. Around 56.8% of patients were able to return to jobs at 6 months follow up. Patients who were paraplegic at the initial presentation were mostly not able to return to jobs. The most common reported complication in the study was intraoperative pedicle breakage.&#x0D; Conclusion: Decompression of the spinal cord plus posterior spine fixation is a safe, reliable and effective method in the management of thoracic and lumbar fractures with significant improvement in outcome in terms of motor power, pain and quality of life.

Cortical Bone Trajectory Pedicle Screw Fixation in Surgical Treatment of Monosegmental Pyogenic Lumbar Spondylodiskitis.

Pedicle screw fixation has been widely used in surgical treatment for infective lumbar spondylodiskitis to prevent instability and deformity. The cortical bone trajectory pedicle screw (CBTPS) fixation is a minimally invasive posterior spinal fixation system that runs from the pedicle's entry point of the caudiomedial region toward the cephalad-divergent direction. Successful results with CBTPS fixation have been reported to treat degenerative and osteoporotic spinal diseases. This study aims to investigate the clinical feasibility of CBTPS in the surgical treatment of pyogenic lumbar spondylodiskitis. We retrospectively retrieved 20 consecutive patients from two academic centers who were surgically treated for monosegmental lumbar pyogenic spondylodiskitis. The primary surgical treatment was the anterior lumbar interbody fusion with decompression, debridement, and reconstruction using an autogenous iliac strut bone graft. One to 2 weeks after the primary surgery, patients underwent a second surgery for posterior instrumentation using conventional pedicle screws (CPS; group I) and CBTPS (group II). Radiographic parameters of the deformity angle at the fusion segment and clinical parameter of visual analog scale (VAS) scores were assessed preoperatively, postoperatively, and at the last follow-up. There were 10 patients in each group. The mean follow-up periods of groups I and II were 51.10 ± 6.95 and 28.60 ± 9.31 months, respectively. Intergroup analysis indicated the two groups area age-matched (p = 0.38), but initial C-reactive protein (CRP; mg/dL, p = 0.04), CRP normalization (months, p = 0.00), and follow-up duration (months, p = 0.00) were heterogeneous. Meanwhile, deformity angles (segmental lordosis) between the two groups were not significantly different preoperatively (p = 0.25), postoperatively (p = 0.13), and at last follow-up (p = 0.38). The intragroup analysis indicated a significant postoperative increase of lordosis in both group I and II (p = 0.00 and 0.04, respectively) with subsequent subsidence. Lordosis remained increased at the last follow-up with or without significance (group I, p = 0.02; group II, p = 0.62). Both groups showed significant improvement in VAS scores (group I, p = 0.00; group II, p = 0.00). In monosegmental lumbar spondylodiskitis, posterior stabilization of the anterior strut bone graft by CBTPS and CPS was comparable via the radiographic parameter of segmental lordosis or deformity angle. Our observation suggests the clinical feasibility of CBTPS in the treatment of relatively mild monosegmental pyogenic lumbar spondylodiskitis.

Dynamic cervical flexion/extension atlantodental interval and functional outcome of the Harms technique for posterior C1/2 fixation: A retrospective analysis of 16 atlantoaxial subluxation cases in a tertiary medical center

BackgroundThe aim of this study was to assess the relationship between the atlantodental interval (ADI) on dynamic flexion/extension cervical radiographs and functional outcomes of posterior spinal fixation by the Harms technique for atlantoaxial subluxation (AAS). Dynamic flexion/extension on cervical radiographs is a standard assessment for evaluation of C1/2 instability in AAS patients. Most studies focused on postoperative ADI and functional outcome, including pain and fusion rate; only few studies compared dynamic ADI change pre- to post-operatively. Material and methodsRetrospectively, we reviewed the medical records of 16 patients who underwent posterior spinal fixation in our center from 2018 to 2019. We used dynamic cervical flexion/extension radiographs to assess the pre- to postoperative change at 12 months in ADI of flexion (ADIf), ADI of extension (ADIe), ADI between flexion/extension (ADIΔ), C1/2 fusion rate and functional outcomes measured by the modified Japanese Orthopaedic Association scale (mJOA scale). Postoperative CT at 3∼12 months assessed screw positioning on the Gertzbein and Robbins classification. ResultsIn the 16 patients included in this study, ADIf, ADIe and ADIΔ were significantly reduced, from respectively 8.0mm, 5.0mm and 3.0mm preoperatively to 4.6mm, 3.8mm and 0.8mm at 12 months’ follow-up. The fusion rate was 81% and the mJOA score recovery rate was 34.9±14.7%. Although the screw malposition rate was higher than in other studies in C1(10%) and C2(20%), there were no new neurologic deficits or worsening of symptoms at follow-up. ConclusionsThe ADIΔ showed significant reduction, showing that the Harms technique of posterior spinal fixation can effective in maintaining the stability of the atlantoaxial joint and improving functional outcome.

Rare association of traumatic diaphragmatic hernia with spinal cord injury: A case report.

Introduction and importanceThe traumatic diaphragmatic hernia could be missed in the background of spinal fractures due to neurological weakness. We report the first case of the management of thoracolumbar fracture-dislocation associated with diaphragmatic injury.Presentation of case53-year-old male transferred from local hospital following fallen from a motorbike on the 4th day after the injury. He was paraplegic from L1 below with sacral root involvement. Further imaging showed fracture-dislocation of the vertebral body at the T12-L1 level and anterior displacement of T11 on T12. The left-sided diaphragmatic hernia was detected by chest x-ray with bowel shadows in the left hemithorax. Emergency laparotomy and diaphragmatic repair followed by a posterior spinal exploration and pedicle screw fixation were done. Early mobilization was done after spinal fixation and the patient is successfully continuing rehabilitation.Clinical discussionThoracolumbar fracture-dislocation associated with the traumatic diaphragmatic hernia is rare. Clinical diagnosis of associated visceral injuries could be delayed due to the neurological deficit of the patient. An initial concern was to repair the life-threatening diaphragmatic hernia. Even current studies showed improved neurological function from early spinal surgery, spinal fixation had to delay as surgery needs a prone position.ConclusionEarly identification and management of traumatic diaphragmatic hernia are life-saving and allows early surgical intervention for the spine. Early reduction and fixation are associated with improved neurological function and will allow early mobilization and reduce hospital and ICU stay.

Distal Junctional Failure Secondary to Nontraumatic Fracture of Lower Instrumented Vertebra: Our Experience and Review of Literature.

Junctional kyphosis (JK) is usually observed in long-level instrumented fusion surgeries. Various contributing factors are proposed, the pre-existing and postoperative spinal imbalance is considered as the single most important factor for the development of JK in adult spinal deformity surgeries. Distal JK (DJK) is seldom reported compared to proximal JK (PJK), and scarce literature exists. We report 2 unique cases of distal junctional failure (DJF) with worsening of neurology, secondary to nontraumatic fracture of a lower instrumented vertebra operated for thoracic canal stenosis without deformity. The first case had acute worsening of the Neurology during follow up and on evaluation, the supine CT and MRI scan revealed well decompressed spinal canal, no implant migration to the canal, no screw loosening, or rod failure. Supine sitting radiographs demonstrated DJK with Fracture and the patient underwent extension of fusion till the pelvis with 3-rod construct and interbody fusion, because of the instability at the L1 level.The second case remained neurologically stable for a month and then had an acute onset of back pain, sensory deficit, and urine incontinence. The supine-sitting dynamic radiograph done demonstrated L1 fracture with DJK at D12-L1 levels. The patient was counseled for extension of fusion, which was deferred by the patient. Patients in our series, had an acute worsening of neurological deficit within a month of posterior spinal fixation. Their supine imaging was almost normal, and the diagnosis of DJK with L1 fracture instability was possible only on a supine-sitting dynamic radiograph. Various factors like obesity, TL kyphosis, osteoporosis, etc. can be the attributing factors for the development of DJK CONCLUSION: A high index of suspicion is required for diagnosing nontraumatic fracture in long-level fusion patients with acute neurological worsening. The supine-sitting dynamic radiograph is an important diagnostic tool for DJF in patients having difficulty standing erect. 4. Application of sitting and supine dynamic radiographs to diagnose instability in patients unable to stand for flexion and extension radiographs.