Transpedicular Fixation Research Articles

Outcome of posterior decompression by L1 laminectomy, transpedicular fixation, posterolateral fusion in burst fracture L1 with incomplete spinal cord injury

Introduction: Burst fractures are more severe than compression fractures as the bones spread out in all directions and may damage the spinal cord, leading to paralysis or nerve injury. This study aims to find the surgical outcomes of Posterior Decompression by L1 Laminectomy in terms of burst fracture with incomplete spinal cord injury. Methods: 48 adult patients with burst fractures with incomplete spinal injury came to NITR from June 2023 to May 2024. In this non-randomized clinical trial, the outcomes of decompression by L1 laminectomy were analysed by using the canal encroachment ratio, while deformity correction was assessed using the sagittal Cobb angle and the percentage of anterior vertebral height for the treatment of L1 burst fracture with incomplete spinal cord injury. Results: The patients were followed up for an average of 12 months. The mean operation time was 154.53 minutes, mean intraoperative blood loss of 48.84 mL, and the mean incision length was 7.78 cm. The canal encroachment ratio decreased significantly, as well as the sagittal Cobb angle, and anterior vertebral percentage height increased. Oswestry Disability Index, and American Spinal Injury Association impairment scale classification were significant. Conclusions: Posterior decompression combined with Transpedicular Fixation and Posterolateral Fusion in the treatment of Burst Fracture L1 with Incomplete Spinal Cord Injury is safe and effective.

Efficacy and safety of short segment pedicle screw fixation in patients with neurologically intact burst fractures of the lower thoracic and lumbar spine: a meta-analysis of studies published over the last 20 years

Objective. To conduct a systematic review and meta-analysis of studies on the surgical treatment of patients with uncomplicated burst fractures of the lower thoracic and lumbar spine and to determine the effectiveness and safety of short transpedicular fixation (TPF) in this patient group.Material and Methods. The study included articles with the following criteria: publication date from January 1, 2004, to December 31, 2023; patient sample descriptions involving uncomplicated burst fractures from T10 to L5; TPF involving one segment adjacent to the fractured vertebra in both cranial and caudal directions without spinal fusion; descriptions of treatment outcomes or complications; and an average follow-up period of at least 12 months. Meta-analysis was conducted using the Comprehensive Meta-Analysis software, version 2.2.064. Depending on the level of heterogeneity (I² test), either a fixed-effects or random-effects model was applied. Begg’s or Egger’s test was used to assess publication bias, and any bias present was corrected using the trim-and-fill method.Results. The application of TPF resulted in a significant reduction in the overall Cobb angle by 5.9 degrees in the percutaneous group and by 7.6 degrees when using a midline approach. Regarding AVBCR (anterior vertebral body compression ratio), a reduction of 24.0 % and 24.8 % was observed in both groups, respectively. The overall complication rates were as follows: superficial infection, 2.2 %; deep infection, 2.0 %; and implant-associated complications, 5.6 %. No patient developed a neurological deficit. The levels of work adaptation W1 and W2 on the Denis scale were achieved in 70.9 % of patients. The overall quality of life, as measured by the Oswestry Disability Index, averaged 13.4 %.Conclusions. Short transpedicular fixation without additional spinal fusion or laminectomy appears to be an effective and safe method for treating burst fractures of the lower thoracic and lumbar spine without neurological deficits. This method allows for regression of kyphotic deformity in the long-term post-injury period by at least 5.9 degrees and restoration of anterior vertebral height by 24 %. The approach demonstrated relatively low overall postoperative complication rates. More than 90 % of patients were able to return to full-time work, either in their previous position or with reduced physical demands.

Prediction of the risks of developing clinically significant frontal imbalance in surgical treatment of severe forms of idiopathic scoliosis with a primary thoracic scoliotic curve

Objective. To create a multifactorial model for predicting the risks of developing clinically significant frontal imbalance in surgical treatment of severe idiopathic scoliosis based on the identification of predictors influencing the main clinical parameters of trunk asymmetry.Material and Methods. The results of surgical treatment of 288 patients with severe forms of idiopathic scoliosis with a primary thoracic scoliotic curve of types 1, 2, 3 according to Lenke (mean 97.6° ± 15.5° according to Cobb) who underwent surgery in 1999–2019 using posterior segmental instrumentation with hook, hybrid and transpedicular fixation, were analyzed. There were 243 female (84.4 %) and 45 male patients (15.6 %). The average age of patients at the time of surgery was 15.3 [10–39] years. The average postoperative follow-up period was 3.5 [2.0–19.5] years. The analysis included clinical and radiological data obtained in the preoperative, postoperative and late postoperative periods. Predictors of the occurrence of frontal imbalance (the distance from the plumb line to the navel and intergluteal fold more than 15 mm, the tilt of the shoulder girdles more than 5° and the tilt of the scapula more than 15°) were identified by building single- and multivariate logistic regression models.Results. In the total cohort, 41 (14.2 %) patients with clinically significant frontal imbalance were identified, including 10 (3,0 %) – with an increase in the distance from the plumb line to the umbilicus of more than 15 mm, 12 (4.2 %) – with an increase in the distance from the plumb line to the intergluteal fold of more than 15 mm, 8 (2.8 %) – with a shoulder girdle tilt of more than 5°, and 11 (3.8 %) – with a scapular tilt of more than 15°. A significant predictor of the risk of developing frontal imbalance was determined as postoperative thoracic scoliotic curve of more than 63°. Multiplicative predictors of the risk of frontal imbalance were identified: postoperative increase in the distance from the plumb line to the umbilicus by more than 15 mm and a tilt of the shoulder girdles by more than 5° with a sensitivity of 88.9 % and 100.0 %, and a specificity of 89.5 % and 100.0 %, respectively (p < 0.001).Conclusion. Identification of multiplicative predictors of the risk of frontal imbalance allows predicting the risk of increasing the distance from the plumb line to the navel by more than 15 mm and the risk of shoulder girdle tilt by more than 5°. To eliminate the risk of frontal imbalance, it is necessary to strive for maximum correction of the thoracic scoliotic curve. When planning surgical treatment using transpedicular fixation for the correction of severe thoracic scoliosis, it is necessary to take into account the patient’s gender and the presence of concomitant neurosurgical, cardiological and pulmonological pathology to prevent shoulder girdle imbalance.

ANALYSIS OF THE EFFECTIVENESS OF INDIRECT SPINAL CANAL DECOMPRESSION IN THE TREATMENT OF BURST FRACTURES AT THE THORACOLUMBAR JUNCTION

Indirect decompression of the spinal canal through ligamentotaxis is one of the methods for remodeling the spinal canal in traumatic stenosis. Objective: To evaluate the effectiveness of indirect decompression of the spinal canal for different morphological types of burst fractures of vertebral bodies at the thoracolumbar junction. Methods. A preoperative and postoperative analysis of computed tomography scans was performed on 59 patients who were treated at the«Romodanov Neurosurgery Institute, National Academy of Medical Sciences of Ukraine» for burst fractures at the thoracolumbar junction. The criterion for the effectiveness of indirect decompression was the area of the spinal canal, measured at the level of injury in the zone of maximum compression. The grading of burst fractures was performed using the classification by F. Magerl et al. (1994). Results. In the preoperative period, the median degree of stenosis in the group of patients was 43.47 % (95 % confidence interval (CI): 37.53–46.22 %). For damage type A3.1, it was 36.9 % (95 % CI: 28.1‒40.5 %), for type A3.2 — 46.1 % (95 % CI: 32.1‒54.5 %), and for type A3.3 — 47.6 % (95 % CI: 37.5‒56.5 %). After surgical treatment, the degree of stenosis decreased by 20.14 % (95 % CI: 15.93‒21.56 %). For type A3.1, the effectiveness was 20.1 % (95 % CI: 9.5‒22.7 %), for type A3.2 — 15.2 % (95 % CI: 7.51‒17.3 %), and for type A3.3 — 21.7 % (95 % CI: 20.8‒26.4 %). The difference between types A3.2 and A3.3 was statistically significant (p = 0.0018). It was found that indirect decompression is most effective with higher degrees of stenosis. For Grade I by D. Wolter (1988), the canalexpansion achieved was 7.07 % (95 % CI: 5.69‒8.65 %), for Grade II — 21.6 % (95 % CI: 20.4‒22.7 %), and for Grade III — 30.3 % (95 % CI: 27.0‒33.6 %). Conclusions. Closed remodeling of the spinal canal with transpedicular fixation and the effect of ligamentotaxis is an effective method for correcting traumatic spinal canal stenosis at the thoracolumbar junction. The effectiveness of the technique is determined by many factors, including the type of burst fracture, the initial degree of stenosis, and the level of injury.

Impact of transpedicular fixation on thoracolumbar junction burst fracture stability: a biomechanical perspective

Introduction. The treatment of burst fractures at the thoracolumbar junction remains a contentious issue in vertebrology. Despite a broad array of surgical interventions available, many surgeons favor isolated posterior stabilization, which can be performed using either minimally invasive or open approaches. However, the biomechanical properties of these methods have not been thoroughly investigated. Objective: This study aims to evaluate the biomechanical stability of the thoracolumbar junction following transpedicular stabilization of a burst fracture at the Th12 vertebra, under different system configurations influenced by lateral flexion. Materials and Methods: A mathematical finite element model of the human thoracolumbar spine, featuring a burst fracture at the Th12 vertebra, was developed. The model included a transpedicular stabilization system with eight screws, simulating “long” stabilization. We examined four variants of transpedicular fixation using both mono- and bicortical screws, with and without the inclusion of two cross-links. Results: The study found that the load borne by the damaged Th12 vertebral body varied depending on the fixation system employed. Specifically, stress levels were 24.0 MPa, 27.3 MPa, 18.4 MPa, and 25.8 MPa for models with short screws without cross-links, long screws without cross-links, short screws with cross-links, and long screws with cross-links, respectively. At the screw entry points in the vertebral arch, the highest stress values were recorded at the L2 vertebra, showing 11.8 MPa, 14.0 MPa, 9.4 MPa, and 13.4 MPa for each respective model. Among the metal construct elements, the connecting rods consistently exhibited the highest stress, with values of 226.7 MPa, 313.4 MPa, 212.4 MPa, and 293.98 MPa, respectively. Conclusion: The results underscore that utilizing cross-links in the stabilization of burst fractures at the thoracolumbar junction, which is only feasible through an open installation, somewhat mitigates stress within the stabilized spinal segment. Meanwhile, the modeling of lateral flexion revealed only minimal differences in stress values between open and minimally invasive installations.

Lumbar Pedicle Dimensions Using CT Scan in Adults of South-Eastern Nigeria as Related to Transpedicular Fixation.

Transpedicular fixation depends on accuracy of the entry points, angle of insertion and pedicular isthmus width for adequate screw insertion. Preoperative measurements of pedicle dimensions reduce the chances of failure during insertion. These pedicle dimensions (transverse diameter, longitudinal diameter, and maximum length of purchase [MLP]) vary with sex and race. Such data, from a large-scale study, are not available for our population. The study aims to evaluate the dimensions of pedicle that are relevant for pedicle screw fixation in Southeast Nigerian population. A prospective multi-slice CT based clinical anatomy study done at Memfys Hospital for Neurosurgery, Enugu. This study is on the lumbar pedicle dimensions that are related to transpedicular fixation (transverse and longitudinal diameters of the pedicle, MLP, pedicle transverse and longitudinal angles of inclination). Sample size (273) was calculated with the confidence interval formula based on the number of patients that present for images. Consent and ethical approval were obtained. The mean values are as follow: LD1 8.22 mm, LD2 7.73 mm, LD3 7.40 mm, LD4 7.16 mm, LD5 6.87 mm TD1 5.05 mm, TD2 5.31 mm, TD3 6.72 mm, TD4 8.27 mm, TD5 11.31 mm, MLP1 46.60 mm, MLP2 47.97 mm, MLP3 47.14 mm, MLP4 45.54 mm, MLP5 43.47 mm TA1 17.8°, TA2 19.34°, TA3 20.80°, TA4 22.00°, TA5 25.70° LA1 19.42°, LA2 18.61°, LA3 18.00°, LA4 17.09°, LA5 16.40°. Unlike transverse diameter, transverse angle, longitudinal dimension, longitudinal angle (LA), MLP there was significant correlation between age and mean LA. The mean values also correlated significantly with the gender. The mean values varied with the different vertebral levels and was good correlations between some of the parameters with age and gender.

Assessment of biomechanical stability of the thoracolumbar junction with a burst fracture of Th12 following surgical stabilization under rotational loading

The thoracolumbar junction is the most vulnerable to traumatic injuries, with over 65 % of injuries to the thoracolumbar spine occurring in this region. Objective: To examine the stress-strain state of the thoracolumbar spine model with a burst fracture of the Th12 vertebra under various transpedicular fixation options influenced by rotational loading. Materials and Methods: A mathematical finite-element model of the human thoracolumbar spine was developed, including a burst fracture of the Th12 vertebra and a transpedicular stabilization system containing eight screws implanted in the Th10, Th11, L1, and L2 vertebrae. Four variants of transpedicular fixation were modelled using short and long screws passing through the anterior surface of the vertebra, with and without two crosslinks. Results: The analysis showed sufficiently high loading values for both the bone structures of the models and the elements of the metal construct. The maximum stress level in the body of the damaged vertebra was 33.2, 26.7, 30.1, and 24.2 MPa, respectively, for models with monocortical screws without crosslinks, bicortical screws without crosslinks, monocortical screws with crosslinks, and bicortical screws with crosslinks. High values were also recorded for the vertebrae adjacent to the damaged one: 13.0, 8.4, 10.9, and 7.1 MPa for the L1 vertebra and 10.2, 8.9, 7.1, and 6.2 MPa for the Th11 vertebra in the respective models. The stress on the supporting rods was registered at 582.0, 512.5, 512.6, and 452.7 MPa respectively. Conclusion: The conducted analysis demonstrated that under rotational loading, the model with monocortical screws without crosslinks shows the highest peak loads at control points, whereas the model with bicortical screws and crosslinks shows the minimum. Meanwhile, models with short screws and crosslinks and long screws without crosslinks exhibit comparable results

Analysis of load distribution after transpedicular stabilization of burst fractures in the thoracolumbar junction

Background. In the structure of all traumatic spine injuries, the thoracolumbar junction is predominant, accounting for over 53 % of all vertebral fractures. One of the most clinically significant types of injuries in this area are burst fractures. The purpose was to study the stress-strain state of the thoracolumbar spine model with a burst fracture of the Th12 vertebra in various transpedicular fixation options under compression load. Materials and methods. The study developed and investigated a finite element model of the thoracolumbar spine with a burst fracture of the Th12 vertebra. The burst fracture was modeled by dividing the vertebral body of the Th12 into several planes, transforming it into separate fragments. The gaps between these fragments were filled with a material that simulated the interfragmentary regenerate. Variants of transpedicular stabilization using different types of screws, mono- or bicortical, and with or without cross-links, were examined. The model was analyzed under compression load. Results. The maximum level of stress among the bone structures directly involved in fixation was registered in the L2 vertebral body. It amounted to 19.9, 15.6, 19.4, and 15.1 MPa, respectively, for models with monocortical screws without cross-links, bicortical screws without cross-links, monocortical screws with cross-links, bicortical screws with cross-links. Simultaneously, the zone of screw entry into the arch of this vertebra shows values of 10.1, 15, 10.2, and 14.3 MPa for these models, respectively. Peak loads on the metal structure elements are observed on the rods, amounting to 212.5, 159.6, 203.7, 142.8 MPa, respectively, for the considered models. Conclusions. The results of the study showed that under the influence of compression load when modeling a burst fracture of the thoracolumbar junction, the use of long screws leads to a reduction in stress levels, both in the elements of the metal structure and in the bone elements of the model, while the use of cross-links has a negligible effect.

Some aspects of biomechanics of the operated thoracolumbar junction following two-level corpectomy

Traumatic spinal injuries pose a significant medico-social challenge, with about 60% of all spine fractures occurring at the thoracolumbar junction. Optimizing care for these patients remains a critical issue, despite the development of numerous surgical and conservative treatment methods, with outcomes still far from ideal. A key factor contributing to the consistently high rate of unsuccessful surgical interventions, which lead to stabilization failures in both the early and late postoperative periods, is the disregard of the biomechanical characteristics of the thoracolumbar junction area. Clinical protocols often regulate intervention methods based on the degree and nature of damage to the thoracolumbar spine as a whole. Enhancing the reliability of fixation, while maintaining the number of transpedicular screws, can be significantly achieved by using cross-links and adjusting screw length. The purpose of our study was to investigate the distribution of loads on the metal construct elements and bone structures in the thoracolumbar junction after extensive decompressive-stabilizing interventions. The load was modeled with a backward tilt. A mathematical finite element model of the human thoracolumbar spine segment was developed, incorporating vertebrae Th9-Th11, L2-L5, with Th12-L1 vertebrae removed, as well as elements of the metal construct—interbody support and a transpedicular system. We modeled four variants of transpedicular fixation using both short and long screws that penetrate the anterior surface of the vertebral body, with and without the use of two cross-links. Stress parameters were monitored at 20 control points in the models. Comparative analysis of the results revealed that models including long bicortical screws and two cross-links demonstrated the best biomechanical performance when the torso was tilted backward, effectively reducing stress in critical areas and enhancing the durability and effectiveness of the fixation.

THE USE OF LABORATORY CRITERIA IN THE RISK ASSESSMENT OF POSTOPERATIVE COMPLICATIONS AFTER TRANSPEDICULAR FIXATION OF THE LUMBAR SPINE

Objective. To investigate the peculiarities of the development of postoperative complications after surgical treatment of degenerative diseases of the lumbar spine with transpedicular fixation of the vertebrae and their relationship with changes in preoperative laboratory parameters. Methods. A retrospective analysis of the biochemical examination data of 35 patients with degenerative diseases of the lumbar spine who underwent discectomy with transpedicular fixation was performed. In four groups of patients with postoperative complications: 10 patients — inflammation of the what fabrics around metal structures and 5 patients — instability of the metal structure. The results of the examination of 20 people without specified complications served as a comparison group. Comparison was made with a control group (20 practically healthy people). Results. Patients have a significant increase in serum ALT activity by 42.29 and AST by 63.55 %, by 38.37 % of the level of CS content, by 37.21 % of total glycoproteins compared to those in the control group. In patients with soft tissue inflammation around the serum instrument zone, the content of LDLP was recorded by 29.27 %, by 23.53 % of the UA, by 12.34 % of TP results higher by 32.01 % ALT activity and 83 %, 49 % AST, 54.96 % AlP activity, 31.40 % — AlP/AcP, 60.47 % — concentration of CS, 95.57 % — total glycoproteins than in persons in the control group. In the serum of patients with the development of instability of metal structures, 28.55 % was observed by activity of the ALT, AlP — by 38.47 %, AcP — by 48.84 %, less by 58.35 % of AlP/AcP, the CHOL content of 13 88 %, higher by 25.43 % of the LDLP content than such persons in the control group. Content of the P was lower by 31.51 % and the Ca/P ratio was higher by 38.95 %, the content of CS by 83.72 %, total glycoproteins — by 48.83 %. Conclusions. Comparative analysis of the results of preoperative clinical and laboratory examination of patients with degenerative spinal diseases with transpedicular fixation which is reflected in the deviations of their preoperative laboratory parameters from such persons with uncomplicated course of the postoperative period after similar surgery.

INFERIOR VENA CAVA COLLAPSIBILITY INDEX AS A NON-INVASIVE METHOD OF ASSESSING THE VOLEMIC STATUS OF PATIENTS DURING SPINE INTERVENTIONS

Objective. To prove the possibility of using non-invasive diagnostics of the volemic state of postoperative patients using ultrasound assessment of inferior vena cava collapsibility index. Methods. The study included 67 patients who underwent transpedicular fixation of the spine with laminectomy. Volemiс status was determined for all participants in two ways: by catheterization of the central vein and determination of central venous pressure, as well as by ultrasound examination of the inferior vena cava and calculation of inferior vena cava collapsibility index. Results. According to the results of the invasive assessment of central venous pressure, patients were divided into 3 groups: group I (patients in hypovolemic state, n = 31), group II (patients in euvolemic state, n = 25) and group III (patients in hypervolemic state, n = 11 ). The average values of central venous pressure indicators in patients of these groups were statistically significantly different from each other (p < 0.01). The difference between the mean values of the inferior vena cava collapse index in the respective groups was statistically significant (p < 0.01). A reliable inverse correlation of very high strength was found between the indicators of inferior vena cava collapsibility index and central venous pressure (p < 0.05). Conclusions. Determination of the patient's volemic state is an extremely important tool for the correct selection of the fluid volume management. Ultrasound assessment of volemic status has a number of advantages, such as the non-invasiveness of the method, wide availability, low price and speed of execution. According to the results of our study, the possibility of using inferior vena cava collapsibility index to assess the volemic status of patients has been demonstrated.

Comparative Study of Transpedicular Fixation with and without Interbody Fusion Cage in Management of L4-L5 Lumbar Degenerative Spondylolisthesis

Comparative Study of Transpedicular Fixation with and without Interbody Fusion Cage in Management of L4-L5 Lumbar Degenerative Spondylolisthesis

Comparison of Transpedicular Fixation with Fusion with Transpedicular Fixation Alone in Spondylolisthesis

Objective: This research evaluated the clinical outcomes of two surgical methods used to treat degenerative lumbar spondylolisthesis in the short term. Fixation through the pedicles with or without inter-body fusion. Utilizing a spinal cage for first- and second-degree condition patients is one of the two methods being compared. Materials & Methods: A total of 28 individual lumbosacral spondylolisthesis were incorporated in the research. Based on the surgical method and fixation technique employed for their care, they were split into two groups at random. Posterolateral intertransverse bone fusion, transpedicular screw fixation, and posterior lumbar decompression operations were performed on Group A. Conversely, Group B underwent posterolateral interbody fusion via the implantation of interbody cages, transpedicular screws, and posterior decompression. Results: There existed no statistically significant association in terms of the two groups that is intraoperative and postoperative complications, clinical outcomes, and patient satisfaction, while noteworthy significance was observed about blood loss and rates of post-operative fusion. Conclusion: Incorporating a spinal implant in conjunction with transverse body fusion results in superior fusion rates and post-operative clinical improvements, while intertransverse bony fusion alone yields comparable patient satisfaction with reduced surgical times.

Transpedicular Fixation for the Alleviation of Neurogenic Claudication and Backache in the Management of Spondylolisthesis

ABSTRACT Objective: To evaluate the surgical outcome of transpedicular fixation for degenerative spondylolisthesis in terms of alleviation of neurogenic claudication and backache Materials & Methods: This prospective observational study was carried out at the department of Neurosurgery, Medical Teaching Institute, Bacha Khan Medical Complex, Swabi over a period of two years i.e. from 1st July, 2021 to 30th June, 2023. Patients presenting with backache and neurogenic claudication and having spondylolisthesis on radiological investigations were subjected to transpedicular fixation and evaluated for improvement in symptoms and fusion rate at 6 months follow up. Results: 60 patients participated in the study. Mean age was 41.42±7.29 years and 63.3% were females. L5-S1 was the most common level involved in 40% of the patients and 50% of the patients had Grade 2 spondylolisthesis. There was significant reduction in mean back-pain score on NRS post-operatively (Pre-op was 6.73±1.94 Vs. post-op was 1.57±1.34, P value = 0.00). The neurogenic claudication reduced from 88.3% Vs. 10% (P value = 0.00). The fusion rate was 90% at 6 month follow up. Conclusion: Transpedicular fixation for degenerative spondylolisthesis is the most effective procedure in terms of relief of neurogenic claudication and backache.

Efficacy Of Short-Segment Transpedicular Fixation for Thoracolumbar Fractures in Terms of Improvement in Neurological Status

Objective: To determine the efficacy of short-segment transpedicular fixation for thoracolumbar fractures in terms of improvement in neurological status. Materials and Methods: A prospective observational research was conducted at Bacha Khan Medical Complex, Swabi, Section of Neurosurgery. Patients having traumatic thoracolumbar fractures with neurological deficits were subjected to short-segment transpedicular fixation and evaluated for post-operative improvement in neurological status at a 6-month follow-up. Results: 48 patients participated in the study. Mean age was 35.69±8.22 years and 60.4% were males. History of falls was the most common mechanism responsible for spinal injury i.e. 56.3%. D12 vertebra was fractured in 43.8% of patients. The leading type of fracture was, AO type B in 37.5% of patients. 23 (47.9%) of the patients showed one or more grade improvements in their neurological status on the ASIA scale at 6-month follow-up. Surgical site infection was the common postoperative complication (8.3%). Conclusion: Short-segment transpedicular fixation is an effective procedure for traumatic thoracolumbar fractures in terms of improvement in neurological status.

Polyetheretherketone Polymer Transpedicular Vertebral System to Treat Vertebral Compression Fracture: A Multicentre Pilot Study of Feasibility and Safety.

To prospectively evaluate the feasibility and safety of a polyetheretherketone (PEEK) polymer transpedicular vertebral system to treat vertebral compression fracture (VCF). Nine consecutive patients (4 men and 5 women; median age 59 [interquartile range: 58-64 years]) were included. The procedure duration, length of hospital stay, and complications were reported. Visual analog scale (VAS) and the Oswestry disability index (ODI) for pain and disability were assessed before and at 2, 6, and 12-month after the procedure. The procedure was technically feasible in all patients. The median procedural time was 64 minutes [45-94]. Only minor adverse events were reported (5 clinically asymptomatic cement leakages) but no severe complications. No post procedural adjacent fracture was reported during follow-up (median: 193 days [147-279]). The median VAS score decreased from 55 mm [50-70] before the procedure to 25 mm [5-30] at 2-month (P = .0003) and 30 mm [15-40] at 6-month follow-up (P = .14). The median ODI decreased from 23% [19-26] before the procedure to 12% [10-14] at 2-month (P = .03) and 12% [9-20] at 6-month follow-up (P = .47). Percutaneous transpedicular fixation of VCF by PEEK implants appears feasible and safe.

Unprecedented journey to 650 transpedicular screws using freehand technique and intraoperative C-arm imaging with technical nuances.

Pedicle screw placement plays a crucial role in treating various cases such as fractures, scoliosis, degenerative spine issues, and kyphosis, reinforcing all three spinal columns simultaneously. While three-dimensional navigation-assisted pedicle screw placement is considered superior, the freehand technique relies on anatomical landmarks and tactile feedback, with observed low complication rates. This was a prospective single-center study conducted over a period of 3 years. It included all patients of dorsal, lumbar, and sacral spinal instability of myriad etiology. Previously operated patients and sick obtunded patients were excluded from the study. In our study, we included 102 patients including 62 (60.7%) males and 40 (39.2%) females. More than half of patients were young in the age group of 20-50 years. Our study population had a varied etiology with 43.1% of patients having vertebral column instability due to trauma. The other etiologies were spondylolisthesis and lumbar canal stenosis (39.2%), Pott's spine (11.7%), tumors (2.9%), and osteoporotic fractures (2.9%). Majority of patients (44.1%) presented with lower backache with radiculopathy. All the transpedicular screws inserted were evaluated by C-arm to assess for screw fixation. In the first year of our study, an average of 4 anteroposterior (AP) and 4 lateral C-arm X-ray shots were taken per screw placement. In the next year, an average of 3 AP and 3 lateral shots and finally in the last year of our study only 2 AP and 2 lateral C-arm X-ray shots were taken per screw placement. Out of 650 screws placed, 4 screws were identified to cause breach with maximum breaches in the lumbar spine fixation. In dorsal spine fixation, there was 1 lateral breach at D10. In lumbar spine fixation, there were 3 breaches: two medial one each at L4 and L5 and one anterior at L2 level. The various complications include wound infection, temporary and permanent neurological deficit, screw breakage, screw misplacement, cerebrospinal fluid leaks, nonunion, and spinal epidural hematoma. Our study has provided strong encouragement to persist with the freehand technique in transpedicular fixation surgeries after a certain number of cases given the minimal breaches and complications observed. There are subtle technical nuances as we increase the number of cases with less exposure of anatomical landmarks and X-rays. Success hinges on experience, adherence to technique, and thorough preoperative planning. Further research and extended follow-up periods are necessary to firmly establish this technique as the gold standard.

BIOMECHANICAL ASPECTS OF TRANSPEDICULAR FIXATION IN THE THORACOLUMBAR JUNCTION AREA: THE INFLUENCE OF LATEROFLEXION

The paradigm shift in surgery of the injured spine during the last few decades is characterized by the active implementation of the principle of stabilization without fusion. This approach significantly expands the possibilities of surgical interventions in terms of the completeness of decompression and spinal axis restoration, but also it determines higher requirements for the reliability of the fixation systems and the uniformity of load distribution on both metal systems and bone structures. Objective. To determine the features of load distribution in the area of the thoracolumbar junction after resection of one vertebra, as well as the effect of the transpedicular screw length and cross-links of the stabilization system. Methods. Mathematical finite-element model of the thoracolumbar human spine was developed. The model simulated the state after surgical treatment of a traumatic injury to the thoracolumbar junction with significant damage to the body of the ThXII vertebra. We studied 4 variants of transpedicular fixation (using monocortical screws and long bicortical screws, as well as two cross-links and without them). Results. When analyzing the stress-stain state of the model, we found that the most loaded bone structures during lateroflexion are the vertebral bodies. For the LII vertebral body, the load values were 17.2, 16.2, 16.3, and 15.5 MPa, respectively, for models with monocortical screws without cross-links, bicortical screws without cross-links, monocortical screws and cross-links, and bicortical screws and cross-links. The peak loads on the transpedicular screws were recorded on those implanted in the body of the ThXI vertebra (24.8, 25.7, 22.8 and 24.3 MPa, respectively, for the considered models) and in the body of the LII vertebra (20.2, 24.6, 19, 7 and 23.7 MPa). Conclusions. The use of long transpedicular screws causes less stress on the bony elements than the short screws. At that time stresses on the screws themselves and the bone tissue around them increase. Сross-links help to reduce stress at all control points on models with both short and long transpedicular screws.

Exploring the Effectiveness of Transpedicular Fixation for Managing Thoracic and Lumbar Tuberculous Spine Disease

Background: Tuberculous spine disease, particularly in the thoracic and lumbar regions, poses a significant health challenge in Pakistan, necessitating effective surgical interventions. Transpedicular fixation has emerged as a promising treatment option, yet there is a paucity of comprehensive studies evaluating its efficacy within this demographic. Objective: The study aimed to systematically assess the effectiveness of transpedicular fixation for treating thoracic and lumbar tuberculous spine disease in Pakistan by analyzing preoperative conditions, surgical details, and postoperative outcomes. Methods: This retrospective cohort study involved 78 patients from the Neurosurgical Ward of Khyber Teaching Hospital, Peshawar, who underwent transpedicular fixation from January 2021 to December 2022. Demographics, preoperative clinical data, radiological findings, intraoperative details, and postoperative outcomes were collected. Statistical analysis was conducted using SPSS version 26, employing Chi-square and t-tests to evaluate outcome significance. Results: The patient cohort comprised 53.85% males, with a mean age of 36.3 years. The lumbar region was the most affected (45%), followed by the thoracic (38%) and thoracolumbar (17%). Postoperative outcomes indicated an improvement in radiological stability from 48.72% preoperatively to 73.08% postoperatively (p=0.001), a non-significant increase in complications (12.82% to 19.23%, p=0.231), and a slight rise in patient satisfaction (84.62% to 88.46%, p=0.453). Conclusion: Transpedicular fixation is effective in improving radiological stability and maintaining high patient satisfaction in the treatment of thoracic and lumbar tuberculous spine disease in Pakistan. The procedure's safety profile is acceptable, though the slight increase in postoperative complications warrants attention.

Surgical treatment of recurrent herniated discs of the lumbar spine depending on risk factors

The study included 61 patients with recurrent intervertebral disc herniation. Thirty patients underwent repeated microdiscectomy without transpedicular fixation, 31 patients - resection of recurrent disc herniation with transpedicular fixation (PLIF technique). The control group included 63 patients without recurrent disc herniation. Mean follow-up period was 3.5 years. Discectomy with transpedicular fixation is characterized by larger extent, prolonged surgery time and rehabilitation period. However, there is lower risk of recurrent disc herniation and CSF leakage. Repeated microdisectomy without transpedicular fixation is characterized by smaller extent and shorter surgery time, as well as faster recovery period. Nevertheless, we have higher risk of recurrent disc herniation and CSF leakage. We developed a method for assessing the probability of recurrent intervertebral disc herniation. This algorithm allows us to predict the probability of recurrent disc herniation in a particular patient with 86.7% accuracy. We proposed an algorithm for choosing surgical treatment of recurrent disc herniation. Microdiscectomy without fixation is advisable for the risk of recurrent disc herniation <30%, discectomy with transpedicular fixation - for risk of disc herniation >30%.