Key risk factors and adverse outcomes in metachronous vertebral osteomyelitis following periprosthetic joint infection: A 5-year retrospective study.

Purpose: Periprosthetic joint infection (PJI) is a leading cause of joint arthroplasty failure, potentially leading to critical complications like vertebral osteomyelitis (VO). The factors contributing to VO after PJI and the outcomes for these patients are not well understood. Our study aims to (1) identify risk factors for VO following PJI and (2) assess the clinical outcomes in these cases. Methods: We included PJI patients treated surgically at our centre from January 2006 to December 2020, excluding those with simultaneous VO post-PJI. Our focus was on patients with VO occurring after PJI, monitored for at least 5 years. Analysis included patient comorbidities, PJI treatment approaches, pathogen identification and clinical outcomes. Results: Of 1701 PJI cases, 21 (1.23%) developed VO. Key risk factors for VO post-PJI were identified: systemic inflammatory response syndrome, substance misuse, polymicrobial infection and undergoing at least three stages of resection arthroplasty (odds ratios: 1.86, 54.28, 52.33 and 31.88, respectively). Adverse outcomes were noted in VO patients, with recurrent VO in 6/21 and repeated PJIs in 18/21 cases. Conclusions: Patients with PJI, especially those with certain risk factors, have an increased likelihood of developing VO and encountering negative outcomes. The potential role of bacteremia in the development of VO after PJI needs further exploration. Level of Evidence: Level III.

Teriparatide alone versus vertebroplasty on pain control and radiographic outcomes after osteoporotic vertebral compression fracture.

PURPOSE: To investigate efficacy of 3-month teriparatide(TPD) and compare this treatment with vertebroplasty in terms of clinical and radiographic outcomes after osteoporotic vertebral compression fractures (OVCFs). METHODS: This is a retrospective matched cohort study. Patients who received conservative treatment with at least 3-month TPD treatment for acute OVCF with at least 6 months follow-up were included. Each enrolled TPD case was matched with 2 vertebroplasty cases using age and gender. 30 TPD cases and 60 vertebroplasty cases were enrolled. Patient-reported pain scores were obtained at diagnosis and 1, 3, 6 months after diagnosis. Radiographic parameters including middle body height, posterior body height, wedge angle and kyphotic angle were measured at diagnosis and 6 months after diagnosis. Fracture non-union and subsequent vertebral fracture were evaluated. RESULTS: TPD treatment showed inferior pain relief to vertebroplasty group at 1 month, but did not show difference at 3 and 6 months after diagnosis. In TPD cases, progression of vertebral body collapse was noted in terms of middle body height and wedge angle at final follow up. Instead, both middle body height and wedge angle increased significantly after operation in the vertebroplasty group. Fracture non-union was confirmed via MRI and 4 TPD patients were diagnosed with non-union (4/30, 13.3%). Subsequent compression fracture within 6 months was significant higher in vertebroplasty group (12/60, 20%) than in TPD group (1/30, 3.3%). CONCLUSION: In acute OVCFs, 3-month TPD treatment alone showed comparable pain improvement and less subsequent spine fracture than vertebroplasty.

Local application of zoledronate inhibits early bone resorption and promotes bone formation.

Nonunion resulting from early bone resorption is common after bone transplantation surgery. In these patients, instability or osteoporosis causes hyperactive catabolism relative to anabolism, leading to graft resorption instead of fusion. Systemic zoledronate administration inhibits osteoclastogenesis and is widely used to prevent osteoporosis; however, evidence on local zoledronate application is controversial due to osteoblast cytotoxicity, uncontrolled dosing regimens, and local release methods. We investigated the effects of zolendronate on osteoclastogenesis and osteogenesis and explored the corresponding signaling pathways. In vitro cytotoxicity and differentiation of MC3T3E1 cells, rat bone marrow stromal cells (BMSCs) and preosteoclasts (RAW264.7 cells) were evaluated with different zolendronate concentrations. In vivo bone regeneration ability was tested by transplanting different concentrations of zolendronate with ß-tricalcium phosphate (TCP) bone substitute into rat femoral critical-sized bone defects. In vitro, zolendronate concentrations below 2.5 × 10-7 M did not compromise viability in the three cell lines and did not promote osteogenic differentiation in MC3T3E1 cells and BMSCs. In RAW264.7 cells, zoledronate inhibited extracellular regulated protein kinases and c-Jun n-terminal kinase signaling, downregulating c-Fos and NFATc1 expression, with reduced expression of fusion-related dendritic cell­specific transmembrane protein and osteoclast-specific Ctsk and tartrate-resistant acid phosphatase (. In vivo, histological staining revealed increased osteoid formation and neovascularization and reduced fibrotic tissue with 500 µM and 2000 µM zolendronate. More osteoclasts were found in the normal saline group after 6 weeks, and sequential osteoclast formation occurred after zoledronate treatment, indicating inhibition of bone resorption during early callus formation without inhibition of late-stage bone remodeling. In vivo, soaking ß-TCP artificial bone with 500 µM or 2000 µM zoledronate is a promising approach for bone regeneration, with potential applications in bone transplantation.

Forcefully engaging rods into tulips with gap discrepancy leading to pedicle screw loosening-a biomechanical analysis using long porcine spine segments.

BACKGROUND CONTEXT: Long-segment pedicle screw instrumentation is widely used to treat complex spinal disorders. Rods are routinely precontoured to maximize assistance on the correcting side of the deformity, but there often exists a residual gap discrepancy between the precontoured rods and screw tulips. No previous research has investigated the diminished pullout strength of the most proximal or distal pedicle screw resulting from a mismatched rod in long-segment pedicle screw instrumentation. PURPOSE: The present study aimed to investigate the decreased pullout force of pedicle screws affected by the gap discrepancy when forcefully engaging a mismatched rod into a tulip in a normal-density porcine spine. STUDY DESIGN: The pedicle screw fixation strength under axial pullout force was compared among three different gap discrepancies between rods and tulips using long porcine spine segments. METHODS: Twelve porcine lumbar vertebrae (L3-L6) were implanted with pedicle screws and rods. Screws on one side had no gap between the tulip and rod (0-mm group), while the most proximal screw on the other side had an intentional gap of 3 mm (3-mm group) or 6 mm (6-mm group). Three hours after forcefully engaging the rod into the tulips at room temperature, the set screws in all specimens were loosened, and each specimen was dissected into individual vertebrae for subsequent pullout testing. RESULTS: The control group exhibited significantly greater pullout strength (1987.68 ± 126.80 N) than the groups from different rod-tulip configurations (p<.05), with significantly greater strength in the 3-mm group (945.62 ± 97.43 N) than the 6-mm group (655.30 ± 194.49 N) (p<.05). Only 47.6% and 33.0% of the pullout strength was retained in the 3-mm and 6-mm groups, respectively, compared to the control group. CONCLUSIONS: Gap discrepancies between rods and tulips can significantly reduce pedicle screw pullout strength, with a correlation between decreased strength and increased gaps. Surgeons should avoid forcefully engaging mismatched rods and consider well-fitted contoured rods in spinal surgery to minimize the risk of screw loosening. CLINICAL SIGNIFICANCE: The gap discrepancy between rod and tulip significantly affected pullout strength, with greater gaps leading to reduced strength. Forcefully engaging mismatched rods into tulips in degenerative spinal surgery should be avoided to minimize the risk of early screw pullout.

Quantitative lateral flow immunoassay for rapid detection of procollagen type I N-terminal propeptide in the monitoring of osteoporosis treatment.

Appropriate follow-up after treatment initiation in patients with osteoporosis is challenging. Serum biomarkers may offer more efficient monitoring of bone mineral density (BMD) than the currently used dual X-ray absorptiometry; however, significant changes in BMD often occur over at least 12 months. During teriparatide treatment for osteoporosis, monitoring with markers such as procollagen type I propeptide (PINP), which is derived from osteoblasts, can provide clinically useful information for disease management. However, rapid and cost-effective methods for detecting serum PINP are lacking, necessitating a point-of-care test (POCT) for enhanced follow-up efficiency in osteoporosis management. For the quantitative detection of PINP, we developed a high-sensitivity lateral flow immunoassay with a stacking pad (sLFIA). We established a calibration equation based on the test line/control line ratio obtained from our PINP sLFIA results of various nonspiked serum samples to calculate the PINP concentrations in 40 serum samples and compared the result with those obtained using a fully automated electrochemiluminescence immunoassay. PINP concentrations between these two methods exhibited excellent correlation (R = 0.991). In addition, we assessed the serum PINP concentrations of patients with osteoporosis treated with teriparatide. At the 3-month follow-up, their PINP levels were nearly twice as high as those at baseline, thus implying that our method can be used for osteoporosis treatment monitoring. Our findings thus indicate that the PINP sLFIA can serve as a POCT for monitoring medication response and managing osteoporosis.

A self-powered multifunctional dressing for active infection prevention and accelerated wound healing.

Interruption of the wound healing process due to pathogenic infection remains a major health care challenge. The existing methods for wound management require power sources that hinder their utilization outside of clinical settings. Here, a next generation of wearable self-powered wound dressing is developed, which can be activated by diverse stimuli from the patient's body and provide on-demand treatment for both normal and infected wounds. The highly tunable dressing is composed of thermocatalytic bismuth telluride nanoplates (Bi2Te3 NPs) functionalized onto carbon fiber fabric electrodes and triggered by the surrounding temperature difference to controllably generate hydrogen peroxide to effectively inhibit bacterial growth at the wound site. The integrated electrodes are connected to a wearable triboelectric nanogenerator (TENG) to provide electrical stimulation for accelerated wound closure by enhancing cellular proliferation, migration, and angiogenesis. The reported self-powered dressing holds great potential in facilitating personalized and user-friendly wound care with improved healing outcomes.

Percutaneous Endoscopic Interbody Debridement and Fusion (PEIDF) Decreases Risk of Sepsis and Mortality in Treating Infectious Spondylodiscitis for Patients with Poor Physical Status, a Retrospective Cohort Study.

Background: Postoperative immunosuppression is associated with blood loss and surgical trauma during surgery and subsequently predisposes patients to increased morbidity. Spine endoscopic surgery has been accepted as an effective surgical technique with less surgical trauma and less blood loss for the complication of infectious spondylodiscitis. Therefore, the aim of this study was to investigate whether PEIDF could reduce the morbidity rates for patients with infectious spondylodiscitis. Methods: We launched a retrospective cohort study on the comparison of the perioperative prognosis between PEIDF and conventional open surgery for single-level lumbar infectious spondylodiscitis in patients with poor physical health (ASA ≥ 4) from 2014 to 2019. Results: Forty-four patients were included in this study. Fifteen of them underwent PEIDF, and the rest of the 29 patients were treated with open surgery. Less surgical blood loss (p < 0.001) and intraoperative transfusions (p < 0.001) with a better decline of CRP (p = 0.017) were statistically significant in patients receiving PEIDF. Patients undergoing conventional open surgery encountered more postoperative sepsis (p = 0.030), a higher qSOFA score (p = 0.044), and prolonged-time for CRP normalization (p = 0.001). Conclusions: PEIDF minimizes a poor postoperative outcome due to less surgical trauma, intraoperative blood loss, and the need for a blood transfusion.

Self-assisted wound healing using piezoelectric and triboelectric nanogenerators.

The complex process of wound healing depends on the coordinated interaction between various immunological and biological systems, which can be aided by technology. This present review provides a broad overview of the medical applications of piezoelectric and triboelectric nanogenerators, focusing on their role in the development of wound healing technology. Based on the finding that the damaged epithelial layer of the wound generates an endogenous bioelectric field to regulate the wound healing process, development of technological device for providing an exogenous electric field has therefore been paid attention. Authors of this review focus on the design and application of piezoelectric and triboelectric materials to manufacture self-powered nanogenerators, and conclude with an outlook on the current challenges and future potential in meeting medical needs and commercialization.

Minimal invasive fixation following with radiotherapy for radiosensitive unstable metastatic spine.

BACKGROUND: Minimally invasive surgery (MIS) has become a feasible option for patients with spinal metastasis, but the effectiveness of percutaneous pedicle screw fixation (PPSF) without decompression in patients with severe cord compression remains unknown. We compared PPSF without decompression with debulking surgery in patients with radiosensitive, unstable, metastatic thoracolumbar spinal cord compression. METHODS: A retrospective study of surgically treated spinal metastasis and spinal cord compression patients was conducted between October 2014 and June 2019. Demographic and pre- and postoperative data were collected and compared between patients treated with minimally invasive percutaneous fixation and external beam radiotherapy (EBRT) (the PPSF group) and those treated with debulking surgery (the debulking group). RESULTS: We included 50 patients in this study. The PPSF group had a significantly shorter operative time (143.56 ± 49.44 min vs. 181.47 ± 40.77 min; p < 0.01), significantly lower blood loss (116.67 ± 109.92 mL vs. 696.55 ± 519.43 mL; p < 0.01), and significantly shorter hospital stay (11.90 ± 9.69 vs. 25.35 ± 20.65; p < 0.01) than did the debulking group. No significant differences were observed between the groups in age, sex, spinal instability neoplastic score, ESCC, Tomita scores, numeric rating scale scores, American Spinal Injury Association Impairment Scale scores, survival rates, and complication rates. Postoperative neurologic function and decrease in pain were similar between the groups. CONCLUSION: The PPSF group had a shorter operation time, shorter length of hospital stay, and less blood loss than did the debulking group. PPSF followed by EBRT is pain relieving, relatively safe and appropriate as palliative therapy.

Risk Factors of Coexisting Septic Spondylitis and Arthritis: A Case-Control Study in a Tertiary Referral Hospital.

INTRODUCTION: In patients under immunosuppression or severe sepsis, it is sometimes manifested as coexisting septic arthritis and spondylitis. The aim of this study is to evaluate and investigate the risk factors of infectious spondylitis associated with septic arthritis. METHODS: The study retrospectively reviewed the patients diagnosed with infectious spondylitis between January 2010 and September 2018 for risk factors of coexisting major joint septic arthritis. RESULTS: A total of 10 patients with infectious spondylitis and coexisting septic arthritis comprised the study group. Fifty matched patients with solely infectious spondylitis were selected as the control group. Major risk factors include preoperative C-reactive protein (p = 0.001), hypoalbuminemia (p = 0.011), history of total joint replacement (p < 0.001), duration of preoperative antibiotics treatment (p = 0.038) and psoas muscle abscess (p < 0.001). CONCLUSION: Infectious spondylitis and septic arthritis are thought of as medical emergencies due to their high mortality and morbidity. Our study evaluated 5 risk factors as significant major findings: hypoalbuminemia (<3.4 g/dL), higher preoperative CRP (>130 mg/L), psoas muscle abscess, longer preoperative antibiotics treatment (>8 days) and history of total joint replacement. Clinicians should pay attention to the patients with those five factors to detect the coexisting infections as early as possible.

Comparison of outcomes between indirect decompression of oblique lumbar interbody fusion and MIS-TLIF in one single-level lumbar spondylosis.

Minimal invasive spinal fusion has become popular in the last decade. Oblique lumbar interbody fusion (OLIF) is a relatively new surgical technique and could avoid back muscle stripping and posterior complex destruction as in minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). Between December 2016 and September 2018, patients with single level degenerative spondylosis were selected to enroll in this retrospective study. A total of 21 patients that underwent OLIF and 41 patients that received MIS-TLIF were enrolled. OLIF showed significantly less blood loss and shorter surgery time compared to MIS-TLIF (p < 0.05). The improvement in segmental lordosis and coronal balance was significantly more in OLIF group than MIS-TLIF group (p < 0.05). When comparing with MIS-TLIF, OLIF was significantly better in Oswestry Disability Index (ODI) and visual analogue scale for back pain improvement at post-operative 6 months (p < 0.05). Both OLIF and MIS-TLIF are becoming mainstream procedures for lumbar degenerative-related disease, especially for spondylolisthesis. However, the indirect decompression of OLIF has shown to have less perioperative blood loss and shorter surgery time than that of MIS-TLIF. In addition, OLIF gives superior outcome in restoring segmental lordosis and coronal imbalance. While both OLIF and MIS-TLIF provide optimal clinical outcomes, upon comparison between the two techniques, the indirect decompression of OLIF seems to be a superior option in modern days.

Early detection and intervention for acute perforated peptic ulcer after elective spine surgeries: a review of 13 cases from 24,026 patients.

BACKGROUND: To determine how perforated peptic ulcers be diagnosed earlier after patients undergoing an elective spine surgery. METHODS: Patients who underwent elective spine surgeries at our hospital between January 2000 and April 2018 and experienced an acute perforated peptic ulcer were included. An age-and gender-matched control group was comprised of 26 patients without a postoperative acute perforated peptic ulcer who received spine surgery during the same period. Medical records and imaging studies were thoroughly reviewed. RESULTS: Thirteen patients were enrolled in the study group, including eight females and five males. Three patients, two females and one male, died of uncontrolled peritonitis during the hospital stay. All patients in the study group experienced the sudden onset of abdominal pain, which was continuous and progressively worsening. Patients with elevated serum amylase, a peptic ulcer history and increased intraoperative blood loss had a tendency to develop a postoperative perforated peptic ulcer. CONCLUSION: Spine surgeons should be highly alert to these risk factors of postoperative perforated peptic ulcers inpatients who has history of peptic ulcer, large amount ofintraoperative blood loss and abnormal high serum amylase level after elective spine surgery. Early diagnosis and emergent surgical intervention promote better outcomes.

The comparison between anterior and posterior approaches for removal of infected lumbar interbody cages and a proposal regarding the use of endoscope-assisted technique.

BACKGROUND: In cases of postoperative deep wound infection after interbody fusion with cages, it is often difficult to decide whether to preserve or remove the cages, and there is no consensus on the optimal approach for removing cages. The aim of this study was to investigate the surgical management of cage infection after lumbar interbody fusion. METHODS: A retrospective study was conducted between January 2012 and August 2018. Patients were included if they had postoperative deep wound infection and required cage removal. Clinical outcomes, including operative parameters, visual analog scale, neurologic status, and fusion status, were assessed and compared between anterior and posterior approaches for cage removal. RESULTS: Of 130 patients who developed postoperative infection and required surgical debridement, 25 (27 levels) were diagnosed with cage infection. Twelve underwent an anterior approach, while 13 underwent cage removal with a posterior approach. Significant differences were observed between the anterior and posterior approaches in elapsed time to the diagnosis of cage infection, operative time, and hospital stay. All patients had better or stationary American Spinal Injury Association impairment scale, but one case of recurrence in adjacent disc 3 months after the surgery. CONCLUSIONS: Both anterior and posterior approaches for cage removal, followed by interbody debridement and fusion with bone grafts, were feasible methods and offered promising results. An anterior approach often requires an additional extension of posterior instrumentation due to the high incidence of concurrent pedicle screw loosening. The use of an endoscope-assisted technique is suggested to facilitate safe removal of cages.

Thermocatalytic hydrogen peroxide generation and environmental disinfection by Bi2Te3 nanoplates.

The highly reactive nature of reactive oxygen species (ROS) is the basis for widespread use in environmental and health-related fields. Conventionally, there are only two kinds of catalysts used for ROS generation: photocatalysts and piezocatalysts. However, their usage has been limited due to various environmental and physical factors. To address this problem, herein, we report thermoelectric materials, such as Bi2Te3, Sb2Te3, and PbTe, as thermocatalysts which can produce hydrogen peroxide (H2O2) under a small surrounding temperature difference. Being the most prevalent environmental factors in daily life, temperature and related thermal effects have tremendous potential for practical applications. To increase the practicality in everyday life, bismuth telluride nanoplates (Bi2Te3 NPs), serving as an efficient thermocatalyst, are coated on a carbon fiber fabric (Bi2Te3@CFF) to develop a thermocatalytic filter with antibacterial function. Temperature difference induced H2O2 generation by thermocatalysts results in the oxidative damage of bacteria, which makes thermocatalysts highly promising for disinfection applications. Antibacterial activity as high as 95% is achieved only by the treatment of low-temperature difference cycles. The current work highlights the horizon-shifting impacts of thermoelectric materials for real-time purification and antibacterial applications.

Percutaneous Endoscopic Interbody Debridement and Fusion for Pyogenic Lumbar Spondylodiskitis: Surgical Technique and the Comparison With Percutaneous Endoscopic Drainage and Debridement.

OBJECTIVE: Surgical treatment of severe infectious spondylodiskitis remains challenging. Although minimally invasive percutaneous endoscopic drainage and debridement (PEDD) may yield good results in complicated cases, outcomes of patients with extensive structural damage and mechanical instability may be unsatisfactory. To address severe infectious spondylodiskitis, we have developed a surgical technique called percutaneous endoscopic interbody debridement and fusion (PEIDF), which comprises endoscopic debridement, bonegraft interbody fusion, and percutaneous posterior instrumentation. METHODS: Outcomes of PEIDF in 12 patients and PEDD in 15 patients with infectious spondylodiskitis from April 2014 to July 2018 were reviewed retrospectively. Outcome were compared between 2 kinds of surgical procedures. RESULTS: Patients in PEIDF group had significantly lower rate of revision surgery (8.3% vs. 58.3%), better kyphosis angle (-5.73° ± 8.74 vs. 1.07° ± 2.70 in postoperative; 7.09° ± 7.23 vs. 0.79° ± 4.08 in kyphosis correction at 1 year), and higher fusion rate (83.3% vs. 46.7%) than those who received PEDD. CONCLUSION: PEIDF is an effective approach for treating infectious spondylodiskitis, especially in patients with spinal instability and multiple medical comorbidities.

Better Functional Outcome and Pain Relief in the Far-Lateral-Outside-in Percutaneous Endoscopic Transforaminal Discectomy.

BACKGROUND: Even though percutaneous endoscopic transforaminal discectomy (PETD) has been widely used for the surgical treatment of lumbar herniated disc, there are only a few studies directly comparing the clinical outcomes between microdiscectomy (MD) and PETD. Therefore, further studies are needed in order to compare the clinical outcomes between PETD and MD on a single level more thoroughly. METHODS: We proposed a far-lateral-outside-in technique for PETD to get an entry point without complex planning and facet violation. From September 2017 to September 2019, a total of 155 patients (69 with PETD and 86 with MD) were enrolled for this retrospective study, with the inclusion criteria: single level between L2 and S1, clinical sciatica for at least 6 weeks, and failed attempts with non-surgical treatments. Patients were excluded due to cauda equina syndrome, progressive neurologic deficits, history of lumbar spinal surgery, endplate modic changes, severe disc degeneration and less than 24 months of follow-up. RESULTS: PETD showed significantly shorter surgery time and less intraoperative blood loss compared to MD. The difference between PETD and MD in VAS back pain (but not VAS leg pain) at follow-up time was significant. The ODI improvement in the follow-up time of 6 months between the 2 groups showed a significant difference (PETD: 31.23±6.59, MD: 39.85±7.81, p < 0.001). MD had a significantly higher chance of postoperative wound infection and poor healing, while PETD was more likely to have recurrence of the herniated disc. CONCLUSION: MD has been the gold standard procedure for LDH. However, with the advanced endoscopic technology and surgical technique, PETD has emerged as an alternative method due to higher functional outcome and less wound problems.