Pyogenic spondylodiscitis is a significant health concern, particularly in older individuals. Minimally invasive surgical techniques, such as posterior fixation, are promising for infection control; however, their mechanisms remain unclear. This study aimed to clarify how posterior fixation promotes infection control in an animal model. Thirty female Wistar rats were used to create a pyogenic spondylodiscitis model by injecting methicillin-sensitive Staphylococcus aureus into the intervertebral space between the 6th and 7th coccygeal vertebrae. Three days post-injection, rats were divided into fixation and control groups. The fixation group underwent posterior fixation with an external fixator, whereas the control group underwent screw insertion alone. Bone destruction was assessed via microcomputed tomography on postoperative days (POD) 7, 14, and 21. Immunohistochemistry for cathepsin K and receptor activator of nuclear factor-kappa B ligand (RANKL) was performed on POD 7 samples to assess osteoclast activity. The fixation group showed less bone destruction than the control group at POD 14 (35% vs. 56%, p = 0.0007) and POD 21 (30% vs. 52%, p < 0.0001). The cathepsin K-positive area was significantly reduced in the fixation group (p = 0.027). RANKL expression was localized within the intervertebral disc in the fixation group, whereas RANKL was strongly expressed on the bone surface adjacent to the disc in control. The RANKL-positive area was also reduced in the fixation group (p = 0.041). Our combined model of pyogenic spondylodiscitis and posterior fixation supports the theory that posterior fixation stability suppresses RANKL and osteoclast expression, promoting infection control.

This study compared patient characteristics, clinical outcomes, and antibiotic durations between patients undergoing posterior fixation for gram-negative rods (GNR) or gram-positive cocci (GPC) thoracolumbar pyogenic spondylitis. In this multicenter retrospective cohort study, 53 patients who underwent minimally invasive posterior fixation for thoracolumbar pyogenic spondylitis were categorized into a GPC or GNR group based on the identified causative organisms. Patient characteristics, surgical outcomes, and postoperative infection control were compared between the two groups to identify factors affecting antibiotic duration. The patients in the GNR group (n = 14) were older (77.2 years versus 70.1 years; p = 0.008), had a higher incidence of a history of abdominal-pelvic infections (4 versus 0; p = 0.003), required longer preoperative antibiotics (5.9 weeks versus 3.0 weeks; p = 0.035), and had more unplanned additional surgeries due to poor infection control (n = 4 versus n = 1; p = 0.014) than those in the GPC group (n = 39). Furthermore, GNR infection independently predicted longer preoperative antibiotic duration (p = 0.002, β = 0.43). Pyogenic spondylitis with GNR is associated with the need for prolonged antibiotic treatment and higher rates of unplanned additional surgeries due to poor infection control as compared to GPC-associated pyogenic spondylitis. Older age and a history of abdominal-pelvic infections tend to complicate the management in these patients; therefore, tailored treatment strategies are required to optimize treatment duration and minimize complications. Not applicable.

Background Minimally invasive posterior fixation surgery for pyogenic spondylitis is known to reduce invasiveness and complication rates; however, the outcomes of concomitant insertion of pedicle screws (PS) into the infected vertebrae via the posterior approach are undetermined. This study aimed to assess the safety and efficacy of PS insertion into infected vertebrae in minimally invasive posterior fixation for thoracolumbar pyogenic spondylitis.Methods This multicenter retrospective cohort study included 70 patients undergoing minimally invasive posterior fixation for thoracolumbar pyogenic spondylitis across nine institutions. Patients were categorized into insertion and skip groups based on PS insertion into infected vertebrae, and surgical data and postoperative outcomes, particularly unplanned reoperations due to complications, were compared.Results The mean age of the 70 patients was 72.8 years. The insertion group (n = 36) had shorter operative times (146 versus 195 min, p = 0.032) and a reduced range of fixation (5.4 versus 6.9 vertebrae, p = 0.0009) compared to the skip group (n = 34). Unplanned reoperations occurred in 24% (n = 17) due to surgical site infections (SSI) or implant failure; the incidence was comparable between the groups. Poor infection control necessitating additional anterior surgery was reported in four patients in the skip group.Conclusions PS insertion into infected vertebrae during minimally invasive posterior fixation reduces the operative time and range of fixation without increasing the occurrence of unplanned reoperations due to SSI or implant failure. Judicious PS insertion in patients with minimal bone destruction in thoracolumbar pyogenic spondylitis can minimize surgical invasiveness.

Introduction: Percutaneous vertebral augmentation techniques, such as balloon kyphoplasty (BKP) and vertebral body stenting (VBS), are commonly used for surgical intervention in osteoporotic vertebral fractures (OVFs). However, markedly unstable OVF cases require additional fixation procedures, prompting the exploration of combined percutaneous vertebral augmentation and posterior fixation. A novel surgical approach involving percutaneous vertebral augmentation with upward penetrating endplate screws (PES) and downward PES, complemented by a short fusion of one above one below, was developed. This study aimed to introduce and report the preliminary outcomes of this technique based on a retrospective analysis of 20 consecutive cases in the short and medium term. Methods: Surgical indications are a vertebral wedge angle difference of 10° or more, vertebral pedicle fractures, posterior wall fractures, and diffuse low-signal changes exceeding 50% on T1-weighted magnetic resonance imaging. The procedure is reserved for highly unstable cases following a comprehensive health assessment. The surgical technique involves prone positioning, fluoroscopy-guided percutaneous vertebral augmentation, and the use of downward PES in the cranial vertebral body and upward PES for the caudal vertebral body by percutaneous technique. The fixation range is one above and one below. Results: The case series of 20 patients, with an average follow-up period of 146.9 days, demonstrates a mean surgical time of 57 min and minimal complications. The advantages of the technique are as follows: ease of performance, minimal fixation range, and time efficiency. Risks, such as potential screw loosening and the need for prolonged follow-up, are acknowledged. Discussion: The technique represents a promising surgical approach that balances the requirements of minimally invasive intervention and relatively robust initial fixation for elderly osteoporotic patients with unstable OVFs. While short- and medium-term results are favorable, long-term observations are needed to further assess its efficacy. This novel technique has a potential to be a valuable surgical option for unstable OVFs.

BACKGROUND CONTEXT Neurogenic bladder dysfunction poses a significant challenge in patients with ossification of posterior longitudinal ligaments (OPLL), affecting both bladder storage and voiding function. Predicting postsurgery bladder function outcomes in OPLL patients is essential for counselling, rehabilitation planning, and discharge. However, no valid prediction rule is currently available for bladder outcomes. PURPOSE This study aims to discover the independent factors for predicting the recovery of bowel function one year after surgery for OPLL patients. STUDY DESIGN/SETTING N/A PATIENT SAMPLE N/A OUTCOME MEASURES N/A METHODS A total of 477 patients treated surgically for OPLL at various departments between 2014 and 2018 were reviewed. The treatment modalities included anterior and posterior surgical approaches and combined both, involving procedures such as corpectomy, discectomy, laminoplasty, laminectomy, and fusion. Exclusion criteria for the study were: (i) patients with a preoperative JOA score of 3 points in bladder function and (ii) patients with less than one year of follow-up after surgery. Among the remaining 192 patients analyzed, consisting of 145 men and 47 women with a mean age of 68 (standard deviation [SD]: 11.0), 2 groups were formed: the improved group (n=125) with a postoperative JOA score increase of 3 points in bladder function, and the unimproved group (n=67) with a postoperative JOA score under 2 points. JOA score consists of 6 domains: motor function in the upper extremities (MU), motor function in the lower extremities (ML), sensory function in the upper extremities (SU), sensory function in the trunk (ST), sensory function in the lower extremities (SL), and bladder function, with a minimum total score of 0 and maximum of 17. Univariable and multivariable analyses were executed using the Cox proportional hazards regression model. This study investigates factors at the initial visit, including age, sex, BMI, comorbidities, preoperative JOA score, OPLL occupation ratio, and K-line. RESULTS The improved group comprised 94 men and 31 women, with a mean age of 65 (standard deviation: 10.8) years. The unimproved group included 51 men and 16 women, with a mean age of 70 (standard deviation [SD]: 10.4) years. Among the improved group, 106 patients (84%) had comorbidities, and 42 patients (34%) had diabetes. The mean OPLL occupation ratio was 44.7 (SD: 16), and the mean preoperative JOA MU score was 2.41 (SD: 0.81), ML 2.05 (SD: 0.4), SU 1 (SD: 0.92), ST 1.66 (SD: 0.53), SL 1.34 (SD: 0.58), and total score of 9.98 (SD: 2.27). In the unimproved group, 56 patients (83%) had comorbidities and 23 patients (34%) had diabetes. The mean OPLL occupation ratio was 45.7 (15.7), and the mean preoperative JOA MU score was 1.93 (SD: 1.13), ML 1.3 (SD: 0.92), SU 0.88 (SD: 0.48), ST 1.35 (SD: 0.70), SL 1.12 (SD: 0.59), and total score of 7.65 (SD: 3.24). In the multivariable analyses, it was found that age (P = 0.003), preoperative JOA ML (P < 0.001), and preoperative JOA ST significantly influenced postoperative bladder function recovery. Using the receiver operating characteristic curve, a preoperative JOA ML cut-off value of 1.5 points (P < 0.001) was identified as a threshold for full bladder function recovery. The sensitivity was 0.582, and the specificity was 0.776. Conversely, a preoperative JOA SL cut-off value of 1.5 points (P < 0.001) was determined to achieve full bladder function recovery. The sensitivity was 0.478, and the specificity was 0.736. CONCLUSIONS Utilizing the receiver operating characteristic curve, a preoperative JOA ML and SL cut-off value of 1.5 points (P < 0.001) were determined for achieving full recovery of bladder function.Age, preoperative JOA ML, and preoperative JOA ST are identified as relevant factors for predicting postoperative bladder function. These findings offer valuable insights for clinicians in optimizing patient care and enhancing prognostic precision in managing OPLL patients with neurogenic bladder dysfunction. FDA Device/Drug Status This abstract does not discuss or include any applicable devices or drugs.

This study aimed to evaluate the difference in treatment duration and unplanned additional surgeries between patients with unidentified causative organisms on empiric antibiotics and those with identified organisms on selective antibiotics in treating thoracolumbar pyogenic spondylitis with minimally invasive posterior fixation. This multicenter retrospective cohort study included patients with thoracolumbar pyogenic spondylitis refractory to conservative treatment who underwent minimally invasive posterior fixation. Patients were divided into the identified (known causative organism) and unidentified groups (unknown causative organism). We analyzed data on demographics, antibiotic use, surgical outcomes, and infection control indicators. We included 74 patients, with 52 (70

Although postoperative recurrent lumbar disc herniation (rec-LDH) is uncommon, it is a challenging situation that requires revision surgery when conservative treatment fails. Recently, an agent inducing chemical dissolution of the nucleus pulposus using condoliase has been approved as a novel intradiscal treatment for LDH. To date, no evidence has been reported regarding its effectiveness in the treatment of postoperative rec-LDH. A 25-year-old man with a history of LDH in L4/5, who underwent transforaminal full endoscopic lumbar discectomy when he was 17 years old, complained of severe pain radiating to his left leg since 1 month. The straight leg-raising test was limited to 25° on the left side. Lumbar T2-weighted magnetic resonance imaging (MRI) showed intracanal, left-sided transligamentous disc herniation at L4/5 with high-signal intensity. Because the conservative treatment with oral analgesics and selective left L5 nerve root block failed, the patient requested intradiscal condoliase injection instead of revision surgery. There were no adverse events reported after the condoliase treatment, and the pain radiating to the left leg improved within 2 weeks. A lumbar MRI performed 2 months after treatment revealed that the disc herniation had significantly decreased in size. The straight leg-raising test examined 3 months after treatment was negative. In this case, the disc herniation was of the transligamentous type and showed a high-signal intensity on T2-weighted MRI which could be suitably treated by condoliase injection therapy. This case report is the first to suggest that intradiscal condoliase injection could be a useful and novel conservative treatment option to treat postoperative rec-LDH.

Thoracolumbar spine injury is frequently seen with high-energy trauma but dislocation fractures are relatively rare in spinal trauma, which is often neurologically severe and requires urgent treatment. Therefore, it is essential to understand other concomitant injuries when treating dislocation fractures. The purpose of this study is to determine the differences in clinical features between thoracolumbar spine injury without dislocation and thoracolumbar dislocation fracture. We conducted an observational study using the Japan Trauma Data Bank (2004–2019). A total of 734 dislocation fractures (Type C) and 32,382 thoracolumbar spine injuries without dislocation (Non-type C) were included in the study. The patient background, injury mechanism, and major complications in both groups were compared. In addition, multivariate analysis of predictors of the diagnosis of dislocation fracture using logistic regression analysis were performed. Items significantly more frequent in Type C than in Non-type C were males, hypotension, bradycardia, percentage of complete paralysis, falling objects, pincer pressure, accidents during sports, and thoracic artery injury (P < 0.001); items significantly more frequent in Non-type C than in Type C were falls and traffic accidents, head injury, and pelvic trauma (P < 0.001). Logistic regression analysis showed that younger age, male, complete paralysis, bradycardia, and hypotension were associated with dislocation fracture. Five associated factors were identified in the development of thoracolumbar dislocation fractures. III.