Posterior Stabilization Procedure Research Articles

Clinical Observation of Posterior Approach for Surgical Treatment of Thoracolumbar Pseudarthrosis in Ankylosing Spinal Disorders

To evaluate the surgical effectiveness of posterior procedure with long segment stabilization for treating thoracolumbar pseudarthrosis associated with ankylosing spinal disorders (ASD) without anterior fusion or osteotomy. Twelve patients with thoracolumbar pseudarthrosis in ASD were enrolled. All patients underwent posterior long-segment stabilization procedures. In some patients, the percutaneous technique or the aid of a robot or O-arm navigation was utilized for pedicle screw implantation. The clinical results were evaluated by means of the Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI). Radiological outcomes were evaluated for bone fusion, anterior column defect, local kyphotic correction (LK) and position of the pedicle screws. All patients experienced effective bone fusion at the sites of pseudarthrosis. The mean operative time was 161.7±57.1 min, and the average amount of blood loss was 305.8 ± 293.2 ml. For six patients who underwent surgery with the assistance of a robot or O-arm navigation, there was no statistically significant difference observed in terms of operative time and mean blood loss compared to those who used the freehand technique (P>0.05). The VAS score, ODI value, and mean LK angle showed significant improvements at the final follow-up (P<0.05). The accuracy of pedicle screw placement was 96%. Posterior surgery with long-segment fixation, without anterior fusion or osteotomy, can achieve satisfactory outcomes in ASD patients with thoracolumbar pseudarthrosis. The application of percutaneous techniques, as well as the assistance of robots or navigation technique may be a good choice for the treatment of pseudarthrosis in ASD patients.

Establishing the Minimal Clinically Important Difference, Substantial Clinical Benefit, and Patient Acceptable Symptomatic State After Arthroscopic Posterior Labral Repair for Posterior Glenohumeral Instability

Background: Posterior glenohumeral instability is an increasingly recognized cause of shoulder pain and dysfunction among young, active populations. Outcomes after posterior stabilization procedures are commonly assessed using patient-reported outcome measures including the Single Assessment Numeric Evaluation (SANE), the Rowe instability score, the American Shoulder and Elbow Surgeons (ASES) score, and the visual analog scale (VAS) for pain. The clinical significance thresholds for these measures after arthroscopic posterior labral repair (aPLR), however, remain undefined. Purpose: We aimed to define the minimal clinically important difference (MCID), substantial clinical benefit (SCB), and patient acceptable symptomatic state (PASS) for the SANE, Rowe score, and ASES score as well as the VAS pain after aPLR. Additionally, we sought to determine preoperative factors predictive of reaching, as well as failing to reach, clinical significance. Study Design: Case-control study; Level of evidence, 3. Methods: This study was a retrospective analysis of patient-reported outcome scores collected from patients who underwent aPLR between January 2011 and December 2018. To determine the clinically significant threshold that corresponded to achieving a meaningful outcome, the MCID, SCB, and PASS were calculated for the SANE, Rowe score, ASES score, and VAS pain utilizing either an anchor- or distribution-based method. Additionally, univariate and multivariate logistic regression analyses were performed to determine the factors associated with achieving, or not achieving, the MCID, SCB, and PASS. Results: A total of 73 patients with a mean follow-up of 82.55 ± 24.20 months were available for final analysis. MCID, SCB, and PASS values for the VAS pain were 1.10, 6, and 3, respectively; for the ASES score were 7.8, 34, and 80, respectively; for the SANE were 10.15, 33, and 85, respectively; and for the Rowe score were 11.3, 60, and 90, respectively. To meet the MCID, male sex (odds ratio [OR], 1.1639; P = .0293) was found to be a positive predictor for the VAS pain, and a lower preoperative SANE score (OR, 0.9939; P = .0003) was found to be a negative predictor for the SANE. Dominant arm involvement was associated with lower odds of achieving the PASS for the ASES score (OR, 0.7834; P = .0259) and VAS pain (OR, 0.7887; P = .0436). Patients who reported a history of shoulder trauma were more likely to reach the PASS for the SANE (OR, 1.3501; P = .0089), Rowe score (OR, 1.3938; P = .0052), and VAS pain (OR, 1.3507; P = .0104) as well as the SCB for the ASES score (OR, 1.2642; P = .0469) and SANE (OR, 1.2554; P = .0444). A higher preoperative VAS pain score was associated with higher odds of achieving the SCB for both the VAS pain (OR, 1.1653; P = .0110) and Rowe score (OR, 1.1282; P = .0175). Lastly, concomitant biceps tenodesis was associated with greater odds of achieving the SCB for the ASES score (OR, 1.3490; P = .0130) and reaching the PASS for the SANE (OR, 1.3825; P = .0038) and Rowe score (OR, 1.4040; P = .0035). Conclusion: To our knowledge, this study is the first to define the MCID, SCB, and PASS for the ASES score, Rowe score, SANE, and VAS pain in patients undergoing aPLR. Furthermore, we found that patients who reported a history of shoulder trauma and those who underwent concomitant biceps tenodesis demonstrated a greater likelihood of achieving clinical significance. Dominant arm involvement was associated with lower odds of achieving clinical significance.

Preventive efficacy of ibuprofen and dexamethasone combination for postoperative pain in posterior vertebral stabilization: a randomized controlled study

Background: Posterior vertebral stabilization procedures often cause acute postoperative pain that can turn into chronic pain if not managed adequately. We compared the interleukin 6 (IL-6) level and pain intensity with preventive use of multimodal analgesia with different combinations of intravenous ibuprofen and dexamethasone in these patients.&#x0D; Methodology: Thirty-nine eligible patients were randomized to receive intravenous ibuprofen 400 mg and dexamethasone 10 mg (Group A), ibuprofen 800 mg and dexamethasone 10 mg (Group B), and ibuprofen 800 mg alone (Group C). The study drugs were injected 30 min before surgical procedure followed by fentanyl 24 h postop in a single‑blinded fashion. Serum levels of IL-6 were measured with ELISA. and pain intensity was measured using numeric rating scale (NRS) at preop, then at 2 h and 24 h postoperatively.&#x0D; Results: There was a significant difference in the NRS scores between all treatment groups (P &lt; 0.005) at all measurement times, where Group B had the lowest value. There was a significant difference between IL-6 levels between all treatment groups (P &lt; 0.005) at all measurement times, where Group B had the lowest value at all measurement times. No side effects were observed in all treatment groups.&#x0D; Conclusion: Preventive combination of ibuprofen and dexamethasone has efficacy and safety in managing acute postoperative pain in posterior vertebral stabilization procedures.&#x0D; Abbreviations: COX – Cyclooxygenase; IL-6 - Interleukin 6; MAC - Minimum Alveolar Concentration; NRS - Numeric Rating Scale; NSAIDs - Non-Steroidal Anti-Inflammatory Drugs; PSA - Patient-Controlled Analgesia&#x0D; Key words: Analgesia; Dexamethasone; Ibuprofen; Interleukin-6; Preventive Medicines; Spinal Surgery&#x0D; Citation: Gaus S, Darise SA, Ala AA, Ahmad MR, Musba AT, Tan CW. Preventive efficacy of ibuprofen and dexamethasone combination for postoperative pain in posterior vertebral stabilization: a randomized controlled study. Anaesth. pain intensive care 2023;27(5):548−554; DOI: 10.35975/apic.v27i5.1851&#x0D; Received: March 22, 2023; Reviewed: August 26, 2023; Accepted: September 04, 2023

A Laminectomy Decompression in Radiculopathy Vertebrae L3-L4, L4-L5: A Case Report

Abstract. Introduction: Spinal tumors are uncommon lesions and affect only a minority of the population. Spinal metastases comprising approximately 97% of masses encountered with spinal imaging and is the most common site of metastasis from breast cancer. The sign and symptom for metastatic spinal tumors is varied from back pain, motoric and sensoric dysfunction and in advanced disease, spinal cord compression.Case Report: In this case, we report a 39-year-old female patient with complaints of weakness in the lower limb with history of breast cancer. The patient underwent a contrast lumbosacral MRI examination and found the patient has metastatic spine tumors. The patient was then planned to undergo laminectomy decompression, tumor resection, and posterior stabilization procedures. Conclusion: Spinal tumors is a condition that can arise within spinal cord itself or from the adjacent structures. It affects only a minority of the population. The hallmark symptom for spinal metastases is back pain. Surgical techniques such as open decompression and stabilization are used from the condition of the patient who has a neurodeficit and compression from radiological examination with good prognosis. Keywords: Breast cancer, Metastatic spinal tumors, Neurosurgery, Weakness

Paper 04: Acromial Morphology Differences in Primary versus Revision Posterior Shoulder Instability Patients

Objectives: Predisposing factors for failure of shoulder posterior stabilization surgery are not well defined. Characterization of revision posterior instability patients allows for insight into potentially identifiable risk factors for failure. Methods: A series of patients who underwent stabilization surgery for posterior shoulder instability as well as revision posterior instability cases performed between 2005-2019 were identified. Patient demographics were collected and glenoid morphology was quantified by measuring posterior bone loss, acromial tilt, and posterior acromial height on shoulder MRIs. Continuous variables were compared with Student’s t-test. Results: 42 active duty servicemembers who underwent successful primary posterior stabilization (primaries, P) and 41 who underwent revision posterior stabilization (revisions, R) and were identified. Mean ages of the primaries and revisions at time of primary surgery were 28.7 (±6.0; 18-39) and 23.0 (±5.2; 18-41) years respectively (p &lt; 0.005). Males made up 92.9% (P) and 92.7% (R) of each group. Mean posterior glenoid bone loss at index MRI was 4.5% (±7.2; P) and 6.3% (±7.8; R) (p = 0.316). Mean index acromial tilt (from horizontal) was 40.9 degrees (±10.2; P) and 28.8 degrees (±10.6; R) (p &lt; 0.005). Index posterior acromial height was 14.2 mm (±7.4; P) and 19.8 mm (±7.6; R) (p = 0.001). In the revision group, the progression of bone loss from index MRI to pre-revision MRI was 6.3% (±7.8) to 6.6% (±6.2) (p = 0.456). Index bone loss greater than 15% was present in 5/41 revision patients; when excluding these, mean index bone loss was 3.4% (±3.3), significantly less than that at pre-revision MRI (p = 0.038). Additional surgery occurred in 9.8% (4/41) of the revision group, and 2/4 separated from the military. In the revision group, 17.1% (7/41) separated, while an additional 7.3% (3/41) remained on active duty with upper extremity activity limitations. Conclusions: Index acromial tilt and posterior acromial height were respectively lower and higher in a population of revision posterior stabilization than in a cohort of patients who underwent successful posterior stabilization. A “high and flat” acromial morphology may predispose patients to failure of standard posterior stabilization procedures, potentially justifying further study into supplemental techniques to decrease failure risk.

Outcomes of Revision Arthroscopic Posterior Labral Repair and Capsulorrhaphy: A Systematic Review.

Failure rates up to 14% have been reported after arthroscopic posterior capsulolabral repair. It is unknown if revision arthroscopic posterior capsulolabral stabilization has inferior restoration of stability and return to sport when compared with primary repair. Optimal management of failed posterior capsulolabral stabilization is unknown. To report outcomes of revision posterior capsulolabral repair and factors that contribute to failure and to determine optimal management of failed posterior stabilization procedures. Systematic review; Level of evidence, 4. A computerized search of the PubMed, EMBASE, and Web of Science databases and manual screening of selected article reference lists were performed in January 2022. Randomized controlled trial, cohort, case-control, and case series studies reporting clinical outcomes of revision arthroscopic posterior capsulolabral repair were eligible. Patient characteristics, indications for revision, intraoperative findings, surgical techniques, and patient-reported outcomes were recorded. Owing to heterogeneity of reported outcomes, data were summarized and presented without pooled statistics. Only 3 of the 990 identified studies met inclusion criteria. The included studies encompassed 26 revision arthroscopic posterior capsulolabral repairs, with follow-up ranging from 2.3 to 5.3 years. The failed index procedure was arthroscopic capsulolabral repair with suture anchors (n = 22) or posterior thermal capsulorrhaphy (n = 4). The primary indications for revision were recurrent instability and pain. Six patients experienced recurrent instability after revision. Patient satisfaction ranged from 15% to 25%. This systematic review of 3 studies demonstrated that the incidence of persistent pain and recurrent instability after revision arthroscopic posterior shoulder stabilization is common, and despite slight improvement in patient-reported outcomes, many patients are dissatisfied with their clinical outcomes. Revision arthroscopic posterior shoulder stabilization appears to have a significant failure rate, and there is need for additional prospective studies to help determine the best intervention for these patients.

Comparison of postoperative IL-6 and IL-10 levels following Erector Spinae Plane Block (ESPB) and classical Thoracolumbar Interfascial Plane (TLIP) block in a posterior lumbar decompression and stabilization procedure: a randomized controlled trial

Background and objectivesThe erector spinae plane block (ESPB) and classical thoracolumbar interfascial plane (TLIP) block can reduce postoperative pain in lumbar surgery. In this study, we compared the efficacy of ESPB and classical TLIP block in providing perioperative analgesia in patients undergoing lumbar posterior decompression and stabilization by comparing postoperative pain, opioid consumption, and IL-6 and IL-10 serum concentrations between ESPB and classical TLIP block.MethodThis was a prospective, double-blinded, randomized controlled trial in tertiary referral hospitals. Forty patients were randomized into two equal groups, each receiving either ESPB or classical TLIP block. The primary outcome was the difference in IL-6 and IL-10 serum concentrations at baseline and 6 h after lumbar posterior decompression and stabilization. The secondary outcome was total opioid consumption and pain score 24 h post-operatively.ResultThere were no significant differences between the ESPB and classical TLIP block groups in pain score, IL-6 and IL-10 concentration change, and total opioid consumption post-operatively. There was a significant difference in the time until the first dose of morphine was needed between the ESPB and classical TLIP block groups (300 min vs. 547.5 min; p = 0.002).ConclusionESPB and classical TLIP block performance during lumbar surgery have comparable pain scores, IL-6 and IL-10 concentration differences pre- and post-operation, and total opioid consumption post-operatively. However, classical TLIP block provides a prolonged duration of analgesia.Trial registrationClinicalTrials.gov NCT04951024.

Effect of Preoperative Embolization on the Intraoperative Bleeding during Posterior Stabilization in Thoracolumbal Fracture Cases at Prof. Dr. R. D Kandou Hospital Manado

Abstract: Embolization is a technique to stop or prevent bleeding by inserting an object, such as an air-filled membrane (balloon), or an embolic material such as foam into a blood vessel to block the blood flow. This study aimed to prove that preoperative embolization might affect and reduce the amount of intraoperative bleeding during the posterior stabilization procedure for thoracolumbal vertebrae fracture. A quasi-experimental method was chosen for this study, and samples were not taken at random. Samples were patients with thoracolumbal vertebrae fracture who underwent the posterior stabilization procedure. Samples were divided into two groups, treated with and without preoperative embolization groups. The treatment was given 24-48 hours before posterior stabilization procedure. The intraoperative bleeding was measured in milliliters. The resulys showed that the average intraoperative blood loss was 283.3 mL, meanwhile of the untreated group was 583.3 mL. The one-way t-test resulted in a p-value of 0.004 at 5% of significance. In conclusion, preoperative embolization could reduce the amount of blood loss during intra-operative posterior stabilization in patients with thoracolumbar vertebral fractures. Further research on preoperative embolization in patient who will undergo posterior stabilization surgery of the thoracolumbal region due to fracture, either mechanically or generatively, is needed. Keywords: preoperative embolization; intraoperative blood loss

Predictors of the Pedicle Screw Misplacement in Patients with Thoracolumbar Fracture

Objectives: To investigate the prevalence and risk factors of the misplacement of the pedicle screw in patients with thoracolumbar spine fracture. Methods: Patients who underwent posterior stabilization procedure due to thoracolumbar spine fracture were included. Association between potential risk factors and the misplacement of the pedicle screw were evaluated by logistic regression analysis. Results: A total of 88 consecutive patients with thoracolumbar spine fracture who underwent posterior stabilization surgery using pedicle screws and rods (mean age 43 ± 14, male 52.3 %). On post-operation CT evaluation, 98 (14.8 %) pedicle screws were misplaced (34 thoracic screws and 64 lumbar screws) and the prevalence of the misplaced pedicle screw was not significantly different between thoracic and lumbar screws (13.2 % vs. 15.8 %, p = 0.347). Among risk factors including location of spine fracture, multiple spine fracture and location of screws, the AO classification of spine fracture was significantly associated with the misplacement of the pedicle screw (OR = 1.27, 95 % CI 1.06 - 1.53, p = 0.011). Conclusion: High grade spine fracture, as assessed by the AO classification, was significantly associated with pedicle screw misplacement in patients with thoracolumbar spine fracture.

Poster 175: Beach Chair Versus Lateral Decubitus Positioning for Primary Arthroscopic Posterior Shoulder Stabilization

Objectives:There are no studies that directly compare beach chair (BC) versus lateral decubitus (LD) position for arthroscopic treatment of posterior instability. In the few systematic reviews evaluating BC vs. LD, no difference had been demonstrated in regard to recurrence and revision rates. Additionally, bone loss was not accounted for in the recurrence rate. The purpose of this study is to identify predictors of shoulder instability recurrence and revision after posterior shoulder stabilization surgery in a young, high demand population and evaluate surgical position and glenoid bone loss as independent predictors of the outcomes of interest, recurrence and revision at short- and mid- term follow-up.Methods:A consecutive series of 147 arthroscopic posterior stabilization procedures were performed by sports medicine certified and fellowship trained orthopaedic surgeons from 2005-2019 in either the BC or LD position. Patients were included if they underwent an isolated primary arthroscopic posterior capsulolabral repair. Patients were excluded if concomitant anterior labral repair was performed at the time of surgery. Shoulders were additionally excluded if magnetic resonance imaging (MRI) was not available at the time of preoperative evaluation, or the patient was lost to follow up. All shoulders were evaluated for glenohumeral bone loss using the best-fit circle technique on the sagittal enface MRI. The primary outcomes of interest were recurrent instability and revision stabilization. Recurrent instability was defined as the presence of a recurrent pain limiting activities with physical exam consistent with recurrent posterior instability per clinical notes in the electronic medical record. Rates of recurrence and revision were calculated among the full cohort among patients with available 1-year or 5-year follow up. Patient and procedure characteristics were compared by BC or LD group using two sample t-tests or Chi-square tests.Results:A total of 147 shoulders with a mean age of 22.6 years (4.82 SD) underwent isolated arthroscopic repair and were followed for a mean 6.93 (3.29 SD) years. The overall recurrent instability and revisions rates were 16% (23/147) and 12% (18/147), respectively. With respect to surgical position, there was no significant difference in recurrence or revision (p-value >0.05). With respect to patient age, anchor number, and bone loss there was no significant difference in recurrence or revision with respect to patient age (p-value >0.05).Conclusions:Among fellowship-trained orthopaedic surgeons, there was no difference in rates of recurrent instability and revision surgery after performing arthroscopic stabilization for isolated posterior shoulder instability in a high demand population in either the BC or LD position.

The Relationship Between Transpedicular Stabilization with Spinal Canal Type.

To analyze the spinal canal type and spinal structure of patients, to determine appropriate preoperative preparation and surgical procedures to prevent material malposition, which is the most common complication of thoracolumbar posterior transpedicular stabilization (TPTS) and is a determiner of its clinical outcomes. A total of 214 cases were examined. TPTS procedures carried out on each thoracolumbar spine were evaluated. Twenty parameters were documented and retrospectively examined in each patient. Laminectomy is not helpful for healing unless there is spinal compression and ligamentotaxis is beneficial for healing. The correlation between the structure of the spinal canal and defective screw delivery found (p < 0.05). The spinal structure formed around the canal should be the first form to evaluate while TPTS applications to protect the spinal cord, which is the focal point of the spinal structure.

Postoperative fungal discitis in immune-competent patients: A series of five patients

Introduction: Postoperative fungal discitis is a rare phenomenon and sparse data are available concerning the cause and adequate treatment guidelines especially in immune-competent patients. This case series reports fungal spondylodiscitis in five immune-competent patients after minimal access spine surgery. Study Design: Retrospective observational study. Materials and Methods: Retrospectively five patients with postoperative fungal discitis were studied. Spine radiographs, gadolinium contrast magnetic resonance imaging, and hematological markers (erythrocyte sedimentation rate/C-reactive protein) were performed in all patients. All patients underwent posterior debridement and stabilization procedure followed by antifungal therapy at our center. The clinical outcomes in the form of Oswestry disability index (ODI) and visual analog scale (VAS) scores were recorded before index surgery, 3 months, and at final follow-up. Results: All patients, four men and one woman with an average age of 55.2 years (45–61), had primary coincidental minimal access spine surgery. The average delay from the primary surgery to onset of pain was 6.4 weeks (4–10 weeks). The average delay from the onset of symptoms, postprimary surgery to secondary surgery, at the author’s institution was 13.2 weeks (11–16 weeks). Preoperative values of ODI and VAS were significantly decreased from 78.8 and 8.2 to 14.4 and 1.4, respectively, at the final follow-up. There was one case of recurrence at adjacent level 3 months after antifungal treatment requiring a revision surgery and recommencement of antifungal treatment. Conclusion: A high index of suspicion is required for prompt diagnosis. Fungal study should be routinely included in tissues biopsied for infective etiology. Antifungal treatment of adequate duration with surgical debridement and stabilization should be the mainstay of treatment.

Percutaneous Versus Open Treatment of Posterior Pelvic Ring Injuries: Changes in Practice Patterns Over Time

To determine how the utilization of open versus percutaneous treatment of posterior pelvic ring injuries in early-career orthopaedic surgeons has changed over time. Case log data from surgeons testing in the trauma subspecialty for part II of the American Board of Orthopaedic Surgery examination from 2003 to 2015 were evaluated. Current procedural terminology codes for percutaneous fixation (27216) and open fixation (27218) of the posterior pelvic ring were evaluated using a regression analysis. A total of 377 candidates performed 2095 posterior ring stabilization procedures (1626 percutaneous, 469 open). Total case volume was stable over time [β = -1.7 (1.1), P = 0.14]. There was no significant change in the number of posterior pelvic ring fracture surgery cases performed per candidate per test year [β = 0.1 (0.1), P = 0.50]. The proportion of posterior pelvic ring cases performed percutaneously increased significantly from 49% in 2003 to 79% in 2015 [β = 1.0 (0.4), P = 0.03]. There was a significant decrease in the number of open cases reported per candidate [β = -0.07 (0.03), P = 0.008]. Early-career orthopaedic surgeons are performing more percutaneous fixation of the posterior pelvic ring and less open surgery. The impact of this change in volume on surgeon proficiency is unknown and warrants additional research.

Risk stratification of vertebral artery vulnerability during surgery for congenital atlanto-axial dislocation with or without an occipitalized atlas.

Variability in dimensions and course of vertebral artery (VA) makes it vulnerable to injury during surgery for congenital atlanto-axial dislocation (AAD) with or without an occipitalized atlas. This prospective study attempts to define anatomical variations that render VA at the craniovertebral junction (CVJ) vulnerable to injury during transoral decompression and posterior stabilization procedures; and, to propose a classification that helps in preoperative risk stratification. A prospective study. 104 patients (65 with AAD; 39 controls) underwent a three-dimensional multiplanar computed tomographic angiogram to study anatomical variations in VA size, course, and anomalous medial deviation as well as in the type of axial isthmus and rotational deformity/tilt at the CVJ. The VA/foramen transversarium diameter; "stretched loop" sign of VA; and C1-2 facet joint angle were also assessed. A medial VA deviation that brought it in close proximity to the trajectory of the surgical approach was evaluated (P ≤ 0.05 significant). An increased predisposition to VA injury was present in 23 (35.4%) patients (persistent first intersegmental artery [n = 20; 30%]; fenestrated VA [n = 1; 1.53%], and low-lying posterior inferior cerebellar artery [n = 2; 3.0%]) where VA crossed the C1-2 facet joint; 8 (12%) with an anomalous medial deviation; 12 (18%) with a high-riding VA at C2 and a narrow axial isthmus; and 13 (20%) with rotation/tilt at the CVJ. A normal score of 5 was obtained in 21 patients; and a score of 6-9 (that progressively indicated an increased vulnerability of VA to iatrogenic injury) in 44 patients. The "AAD with an occipitalized atlas" group was associated with a significant medial deviation of VA (right: P = 0.00 and left: P = 0.001). A preoperative detailed risk assessment of anatomical variations in the size and course of VA at the CVJ significantly reduces chances of its iatrogenic injury.

Integrity of “Damage Control” Posterior Spinal Fixation Constructs for Polytrauma Patients in the ICU Setting: A Biomechanical Investigation

Spine damage control procedures involve an early limited posterior stabilization procedure performed during the first 24 hours, and later followed by definitive stabilization in a second stage when the patient is in a physiologically more stable status. Because these patients will experience minimal activity during this phase in the intensive care unit, less instrumentation may be adequate to stabilize the spine.

Commentary on: "L4 and L5 Spondylectomy for En Bloc Resection of Giant Cell Tumor and Review of the Literature".

Giant cell tumor (GCT; also known as osteoclastoma) is a locally aggressive, intermediate primary bone tumor characterized by osteoclast-like, multinucleated giant cells and the overexpression of receptor activator of nuclear factor kB ligand (RANKL) produced by stromal tumor cells. The tumorigenesis seemed to be associated with mutations of a histone (H3F3A) gene. Prevalence of GCT can be different in different regions/ethnical groups; e.g., GCT is rare in the United States—approximately 4 to 5% of primary bone tumors—but more often occurs in China where it is 10 to 20%.1 Local recurrence is common in surgically treated cases. Globally, malignant transformation has been described in 10% of cases, and lung metastases have been described in 1 to 4% of cases. Metastasizing can occur in benign, primary lesions as well and more frequently in recurrent GCTs and in spinal lesions.2 3 According to the Enneking surgical staging system, GCT is rarely S1 (latent); in 90% of cases, it is S2 (active with extensive cortical thinning and bulging) or S3 (aggressive with soft-tissue component). Management of GCT is often challenging and requires a multidisciplinary approach. In the spine, the osteolytic lesion can result in pathological fracture and consequential instability. Furthermore, the locally aggressive expansion of the tumor can cause neurological symptoms even in its early stage. The Enneking appropriate, en bloc resection of an S3 spinal lesion is a technically challenging surgery with high risk for perioperative complications and functional loss. The case report of Santiago-Dieppa et al demonstrates the complexity of such a surgery. Regarding the differential diagnosis, on one hand, the imaging studies present the typical diagnostic findings in the case of spinal GCT: lytic, aggressive tumor in L4–L5 with local extension across the L4–L5 disc and to the spinal canal. On the other hand, the patient was 58 years old. That age is not typical for the appearance of a GCT, which is usually diagnosed in the second to fourth decade. The patient had local and irradiating pain but no neurological symptom. Considering the unpredictable nature of the tumor and the high risk for local recurrence, the authors performed an en bloc L4–L5 spondylectomy followed by lumbopelvic reconstruction. The description of the technical details of the two-stage surgery clearly shows the difficulty of the management of such a patient; however, more data on the total time of the surgery, blood loss, and hospital stay would have been more informative. In the reported case, the sagittal alignment is properly reconstructed, but I would have been also interested about the bone-grafting procedure, which is the key element of the long-term stability of the lumbopelvic reconstruction. Despite the proper surgical technique and the careful perioperative care, complications occur in almost all of these patients. The reported deep wound infection and CSF leak are the most common complications after en bloc lumbar spondylectomies and lumbopelvic stabilization procedures. However, in some cases, the short- and long-term outcome of extended spinal surgery is not as good as in this patient. The recently described pathological importance of the RANKL in the tumorigenesis of GCT led to human trials of the anti-RANKL monoclonal antibody (denosumab) in the management of the disease. Osteoclasts and their progenitors are dependent on RANKL, and the giant cells in the tumor produce unknown factors important for the survival of the stromal tumor cells. Denosumab was originally developed for the treatment of osteoporosis, but its inhibitory effect on osteoclasts blocks the bone resorption and the tumor progression in GCT. Moreover, in the absence of RANKL, the less cellular stroma starts to produce new osteoid matrix. After the successful phase 1 and 2 trials, denosumab was recently registered for the treatment of unresectable GCTs. Most of these studies comprised patients with GCT in the appendicular skeleton. The first report, with medium-term follow-up, about the use of denosumab in spinal GCT has been recently published by Mattei et al who treated successfully a 22-year-old female with a C2 GCT, applying denosumab after a posterior stabilization procedure.4 The open-label, parallel-group, phase-2 study about the safety and efficacy of denosumab in GCT also included 75 spinal cases (26.5%).5 In the overall cohort, use of the drug was associated with the inhibition of tumor progression and the reduced need for morbid surgery with an acceptable safety profile. Unfortunately, sub-analysis of spinal cases was not reported in this study, despite the importance of the possible surgical morbidity–reducing effect. The first results promise to bring significant changes to the current therapeutic standards, but further multicentric studies on the effect of denosumab in spinal GCT are required to include the drug into the first-line treatment.

Dynamic stabilization: a nidus for infection?

Introduction: Dynamic stabilization offers an adjunct to fusion with motion preservation. In comparison, standard instrumented fusion (if) consists of titanium screws and rods/plates, which do not allow for motion at the level of the fusion. The reported infection rate following a standard if ranges from 0.2% to 7%. Methods: a retrospective chart review of 142 patients who underwent posterior lumbar stabilization procedures was conducted. Ten patients received dynamic stabilization and 132 patients had a standard if. Rates of infection, requiring hardware removal, were compared between the aforementioned groups. Results: Of the 132 patients undergoing posterior if, three developed a deep wound infection requiring removal of hardware (2.3%). Of the 10 patients undergoing dynamic stabilization, three developed a deep wound infection (30%) with 2 requiring removal of hardware (20%), secondary to persistent deep wound infection or osteomyelitis at the pedicle screw sites. There was a significantly increased risk of deep wound infection (p < 0.0001) with the use of dynamic stabilization compared to standard if. Conclusions: Our series demonstrates that the infection rate in patients undergoing dynamic stabilization is higher than the infection rate for instrumented fusion without a significant difference in comorbidity scores. We postulate that the polycarbonate urethane spacer acts as a medium for bacteria, whereas the titanium screws and rods are smooth, solid, and inert, resulting in a lower risk of infection.

Management of Vertebral Malignant Tumors: Clinical and Radiographic Study

26 patients underwent decompression-stabilization procedures for their malignant spinal lesions. Fifteen were females and 11 males. Their average age was 60.6 years (range 18-73 years). These patients were classified according to extent of involvement of the spine. One column was involved in 1/26 (3.8%) case, two in 11/26 cases (42.3%) and three in 14/26 cases (53.8%). A posterior approach alone was done in 8/26 (30.8%) patients while a combined anterior and posterior approaches were done in 18/26 (69.2%) cases. A variety of posterior stabilization procedures were used. Out of 24 patients who were able to attend the follow-up 16 (66.7%) were able to walk, five (20.8%) were paraparetic, and 3 patients (12.5%) were paraplegic. Patients with combined approach showed higher percentage of neurologic improvement (62%) while patients with posterior approach showed only 35% improvement in their neurologic status. Accordingly results obtained from direct anterior approaches using corpectomy and anterior reconstruction of the anterior and middle columns have produced the best results in terms of neurological improvement. Almost all of our patients had 2 or 3 columns involvement but the results did not support the three columns theory where we could not correlate any significant results, regarding pre- or post-operative radiographic measurements (mechanical instability) and pre- or post-operative neurologic findings (neurologic instability), with the number of involved columns.

Surgical options for lumbosacral fusion: biomechanical stability, advantage, disadvantage and affecting factors in selecting options

Numerous surgical procedures and instrumentation techniques for lumbosacral fusion (LSF) have been developed. This is probably because of its high mechanical demand and unique anatomy. Surgical options include anterior column support (ACS) and posterior stabilization procedures. Biomechanical studies have been performed to verify the stability of those options. The options have their own advantage but also disadvantage aspects. This review article reports the surgical options for lumbosacral fusion, their biomechanical stability, advantages/disadvantages, and affecting factors in option selection. Review of literature. LSF has lots of options both for ACS and posterior stabilization procedures. Combination of posterior stabilization procedures is an option. Furthermore, combinations of ACS and posterior stabilization procedures are other options. It is difficult to make a recommendation or treatment algorithm of LSF from the current literature. However, it is important to know all aspects of the options and decision-making of surgical options for LSF needs to be tailored for each patient, considering factors such as biomechanical stress and osteoporosis.

Can posterior dynamic stabilization reduce the risk of adjacent segment deterioration?

The aim of this study was to systematically review the relevant literature to develop a benchmark for the incidence of adjacent segment degeneration (ASDeg) and adjacent segment disease (ASDis) following the posterior dynamic stabilization (PDS) procedure and to investigate whether conclusions can be made with regard to the isolated PDS procedure in reducing the risk of ASDeg and ASDis compared with fusion, and with regard to the role of additional PDS devices implanted adjacent to fusion in protecting from ASDeg and ASDis caused by the neighboring fusion. We retrieved electronic databases of Medline, Ovid and Cochrane Central Registry of Controlled Trials, combined with a supplemental hand search. Thirty-one articles met our inclusion criteria. The pooled incidence of ASDeg and ASDis following PDS procedure was 16.4% and 5.5% respectively. Data from comparative studies showed a significantly lower incidence of ASDeg and nonsignificantly lower incidence of ASDis following PDS than following fusion surgery. Further, the additional PDS devices implanted adjacent to fusion could significantly reduce the risk of ASDeg and nonsignificantly decrease that of ASDis caused by fusion. These results suggested relative success of the PDS procedure in protecting against ASDeg and ASDis.