Risk Factors for 90-Day Readmission Among Patients with Metastatic Spine Tumors in South Korea: A Nationwide Population-Based Study.

BACKGROUND: Population-based studies on the cause of readmission within 90 days after surgery or radiotherapy for metastatic spine tumors are scarce. We aimed to investigate the risk factors for readmission within 90 days after initial surgical or radiation treatment for metastatic spine tumors. METHODS: Patients who were diagnosed with metastatic spine tumors between 2012 and 2019 and underwent spinal magnetic resonance imaging within 1 year were classified according to treatment (surgical or radiotherapy groups), and the causes of the 90-day readmission and patient characteristics were compared. RESULTS: Overall, data from 15,815 patients (surgical group, 13,974 patients; radiotherapy group, 1841 patients) were evaluated. Radiotherapy was preferred in younger and male patients with a high Charlson Comorbidity Index, whereas surgery was mainly performed in patients with lumbar metastasis. Radiotherapy, age of 30-69 years, male sex, and Charlson Comorbidity Index >1 increased the risk of 90-day readmission in patients with metastatic spine tumors. The main causes of 90-day readmission among patients with metastatic spine tumors who received radiotherapy included tumor recurrence, chemotherapy, radiotherapy, and treatment of other organ metastases with radiotherapy. CONCLUSIONS: These study findings offer a better understanding of the causes of readmission following radiotherapy or surgical treatment in patients with metastatic spine tumors, and these results can help reduce postoperative morbidity and medical costs among these patients.

Deep Learning Method for Precise Landmark Identification and Structural Assessment of Whole-Spine Radiographs.

This study measured parameters automatically by marking the point for measuring each parameter on whole-spine radiographs. Between January 2020 and December 2021, 1017 sequential lateral whole-spine radiographs were retrospectively obtained. Of these, 819 and 198 were used for training and testing the performance of the landmark detection model, respectively. To objectively evaluate the program's performance, 690 whole-spine radiographs from four other institutions were used for external validation. The combined dataset comprised radiographs from 857 female and 850 male patients (average age 42.2 ± 27.3 years; range 20-85 years). The landmark localizer showed the highest accuracy in identifying cervical landmarks (median error 1.5-2.4 mm), followed by lumbosacral landmarks (median error 2.1-3.0 mm). However, thoracic landmarks displayed larger localization errors (median 2.4-4.3 mm), indicating slightly reduced precision compared with the cervical and lumbosacral regions. The agreement between the deep learning model and two experts was good to excellent, with intraclass correlation coefficient values >0.88. The deep learning model also performed well on the external validation set. There were no statistical differences between datasets in all parameters, suggesting that the performance of the artificial intelligence model created was excellent. The proposed automatic alignment analysis system identified anatomical landmarks and positions of the spine with high precision and generated various radiograph imaging parameters that had a good correlation with manual measurements.

Traumatic spinal cord injury in South Korea for 13 years (2008-2020).

Traumatic spinal cord injury (TSCI) has significant physical, psychological, and socioeconomic impacts. However, the epidemiological characteristics and treatment patterns of TSCI in South Korea remain unclear. This study aimed to investigate TSCI incidence and treatment behaviors in South Korea from 2008 to 2020. We included data from 30,979 newly diagnosed TSCI patients obtained from the Health Insurance Review and Assessment Service (HIRA). Treatment trends, location of surgery, surgical method, comorbidities, factors affecting hospital stay, and risk factors affecting readmission were analyzed. Patients were divided into the surgery group [n = 7719; (25%)] and the non-surgery group [n = 23,260; (75%)]. Surgical cases involved cervical (64%), thoracic (17%), and lumbar/sacral (19%) lesions. Anterior fusion (38%), posterior fusion (54%), and corpectomy (8%) were the surgical methods. Surgical treatments increased annually. Factors influencing hospital stay included male sex, older age, and higher Charlson comorbidity index (CCI). Female sex and higher CCI scores were associated with readmission. In conclusion, a quarter of all TSCI patients underwent surgery, with an upward trend. Risk factors for longer hospital stays were thoracic spine injury, older age, higher CCI, and male sex. Risk factors for readmission included age range of 40-59 years, lumbar/sacral spine injuries, CCI score of 2, and female sex.

Finite Element Analysis of Stress Distribution and Range of Motion in Discogenic Back Pain.

OBJECTIVE: Precise knowledge regarding the mechanical stress applied to the intervertebral disc following each individual spine motion enables physicians and patients to understand how people with discogenic back pain should be guided in their exercises and which spine motions to specifically avoid. We created an intervertebral disc degeneration model and conducted a finite element (FE) analysis of loaded stresses following each spinal posture or motion. METHODS: A 3-dimensional FE model of intervertebral disc degeneration at L4-5 was constructed. The intervertebral disc degeneration model was created according to the modified Dallas discogram scale. The von Mises stress and range of motion (ROM) regarding the intervertebral discs and the endplates were analyzed. RESULTS: We observed that mechanical stresses loaded onto the intervertebral discs were similar during flexion, extension, and lateral bending, which were greater than those occurring during torsion. Based on the comparison among the grades divided by the modified Dallas discogram scale, the mechanical stress during extension was greater in grades 3-5 than it was during the others. During extension, the mechanical stress loaded onto the intervertebral disc and endplate was greatest in the posterior portion. Mechanical stresses loaded onto the intervertebral disc were greater in grades 3-5 compared to those in grades 0-2. CONCLUSION: Our findings suggest that it might be beneficial for patients experiencing discogenic back pain to maintain a neutral posture in their lumbar spine when engaging in daily activities and exercises, especially those suffering from significant intravertebral disc degeneration.

The Effect of Evogliptin Tartrate on Controlling Inflammatory Pain.

Background: Evogliptin tartrate inhibits dipeptidyl peptidase-4 (DPP-4), boosting glucagon-like peptide 1 (GLP-1) secretion and improving insulin release and glucose tolerance, while also exerting anti-inflammatory effects. We investigated its anti-inflammatory and analgesic effects. Methods: Forty male Sprague Dawley rats were divided into (N = 10 in each): (1) naïve, (2) complete Freund's adjuvant (CFA) inflammation + evogliptin tartrate (once for 10 mg/kg) (CFAE), (3) CFA + vehicle (same volume with normal saline with evogliptin tartrate/once) (CFAV), and (4) CFA + indomethacin (5 mg/mL/kg/1 time) (CFAI) groups. CFA was injected subcutaneously into rat plantar regions, and medications (evogliptin tartrate, vehicle, and indomethacin) were administered orally for 5 days. Post treatment, blood from the heart and plantar inflammatory tissue were collected to assess inflammatory cytokines. Evogliptin tartrate effects on controlling inflammation and pain were evaluated by measuring rat plantar paw thickness, paw withdrawal threshold, dorsal root ganglion (DRG) resting membrane potential, DRG action potential firing, and cytokine (TNF-α and IL-1ß) levels. Results: Compared with the naïve group, plantar paw thickness, cytokine (TNF-α and IL-1ß) levels, DRG resting membrane potential, and DRG action potential firing increased, whereas the paw withdrawal threshold decreased in all CFA groups. However, CFAE and CFAI rats showed recovery. The degree of CFAE recovery resembled that observed in the CFAI group. Conclusions: Evogliptin tartrate mirrored the anti-inflammatory pain relief of indomethacin. We aim to broaden its use as an anti-inflammatory drug or pain relief drug.

What are the risk factors for a second osteoporotic vertebral compression fracture?

BACKGROUND CONTEXT: Osteoporosis is characterized by decreased bone strength and an increased risk of fracture. Osteoporosis-related fractures are associated with increased morbidity, mortality, dysfunction, access to health care, health-care costs, and reduced quality of life. Therefore, preventing osteoporotic vertebral compression fractures (OVCF) is important. Secondary OVCFs often occur after the first OVCF. PURPOSE: This study aimed to identify risk factors for a second OVCF after a first OVCF. STUDY DESIGN: Retrospective observational study. PATIENT SAMPLE: One hundred seventy-eight patients from a single institution who had their first OVCF between January 1, 2000 and December 31, 2019 were enrolled in this study. OUTCOME MEASURES: The following data were observed for all cases: patient demographics, bone mineral density, and pelvic parameters. METHODS: We retrospectively reviewed patients from a single institution who had their first OVCF between January 1, 2000 and December 31, 2019. Demographic factors, medication (oral bisphosphonate, zoledronic acid, denosumab), bone mineral density (BMD), body mass index (BMI), fat, and muscle amount of the trunk using dual-energy X-ray absorptiometry (DEXA), and pelvic parameters (lumbar lordosis, sacral slope, pelvic tilt, pelvic incidence minus lumbar lordosis) were investigated. RESULTS: Of 178 patients who had an OVCF, 68 (38.2%) had a second OVCF. Patients were followed up for >2 years and wore braces for an average of 6 months. The mean age was 71.9±8.63 years, mean BMD T-score was -3.1±1.09, and mean BMI was 23.3±2.96. Comparing those with and without a second OVCF, the smaller the BMD T-score and trunk muscle mass to fat ratio, the more likely a second OVCF occurred (p<.05). There were fewer second OVCF cases in the injection medication group than in the peroral group (p<.05). There were no significant differences in radiologic parameters between these groups. CONCLUSIONS: Patients who had a second OVCF had an average of 21.3 months after the first OVCF. Risk factors for a second OVCF are low T-scores in the femur, and low M/F ratio of the trunk, android, and gynoid regions. For patients with an OVCF, injection medications may be advisable.

Clinical features and prognostic factors of spinal metastatic pancreatic cancer: A retrospective observational study.

Pancreatic cancer is an aggressive malignant cancer that shows the lowest survival rates. Recently, the 5-year survival rate of pancreatic cancer has been increasing, owing to early diagnosis and therapeutic advancement. The purpose of this study was to investigate the clinical characteristics and significant prognostic factors of spinal metastatic pancreatic cancer. Seventeen patients diagnosed with spinal metastases originating from pancreatic cancer from January 2005 to December 2022 were divided into 2 groups: those who underwent spinal surgery and those who did not. We collected patients' demographic data, clinical features, prognosis, and radiologic data. Age, sex, neurologic symptoms, symptom duration, metastasis location, non-neurologic symptoms, adjuvant therapy, overall survival, survival after spinal metastasis, pain score, and quality of life were compared. The average age was 64.05 (50-80) years. The average interval from pancreatic cancer diagnosis to spinal metastasis diagnosis was 12.53 (0-39) months. Eleven patients underwent spinal surgery, while six did not. Preoperative European Cooperative Oncology Group performance status score of the surgery group was 1.91 ± 1.04 and that of the non-surgery group was 2.5 ± 0.84. Survival time after spinal metastasis in the surgical group was 6.14 ± 6.0 months, while that in the non-surgery group was 2.54 ± 2.38 months. The 1-year survival rate after spinal metastasis was 18% in the surgical group, while that of the non-surgery group was 0% (P = .042). Pancreatic cancer patients with spinal metastases showed poor prognoses and extremely short survival rates. Despite poor prognosis, appropriate surgical treatment may improve prognoses.

Unsubtracted Roadmap Technique for Preventing Cement Leakage During Percutaneous Vertebroplasty: A Retrospective Cohort Study.

OBJECTIVE: To determine the effectiveness of the unsubtracted roadmap technique (USRT) for decreasing cement leakage (CL) during percutaneous vertebroplasty (PVP). METHODS: In this retrospective cohort study, patients who underwent PVP between January and November 2018 were included. Patients were divided into the unsubtracted roadmap (UR) (n = 20) and conventional venography (CV) (n = 22) groups. USRT was performed before cement injection in the UR group. Computed tomography was performed on the first day after PVP in both groups to assess the CL. The vertebral height restoration rate was confirmed by radiography before and after the procedure. The CL location was classified as basivertebral vein (type B), segmental vein (type S), or cortical defect (type C). Visual analog scale and Oswestry Disability Index scores before and after surgery were calculated to confirm clinical outcomes. RESULTS: Based on the computed tomography images, CL occurred in 7 (34.78%) and 15 (63.64%) cases in the UR and CV groups, respectively. Number of CL type B, S, and C in the UR and CV groups were 2 and 6, 3 and 6, and 2 and 3, respectively. The injected cement volume was not significantly different between the UR (4.86 mL) and the CV (4.75 mL) groups (P = 0.450). Regarding vertebral body height restoration (P = 0.856) and clinical outcomes, there were no significant differences between both groups. Radiation exposure was significantly less in the UR group (P = 0.019). CONCLUSIONS: USRT is an effective method for reducing CL and radiation exposure during PVP.

Artificial Intelligence for Neurosurgery : Current State and Future Directions.

Artificial intelligence (AI) is a field of computer science that equips machines with human-like intelligence and enables them to learn, reason, and solve problems when presented with data in various formats. Neurosurgery is often at the forefront of innovative and disruptive technologies, which have similarly altered the course of acute and chronic diseases. In diagnostic imaging, such as X-rays, computed tomography, and magnetic resonance imaging, AI is used to analyze images. The use of robots in the field of neurosurgery is also increasing. In neurointensive care units, AI is used to analyze data and provide care to critically ill patients. Moreover, AI can be used to predict a patient's prognosis. Several AI applications have already been introduced in the field of neurosurgery, and many more are expected in the near future. Ultimately, it is our responsibility to keep pace with this evolution to provide meaningful outcomes and personalize each patient's care. Rather than blindly relying on AI in the future, neurosurgeons should gain a thorough understanding of it and use it to enhance their patient care.

Immediate postoperative lumbar spine magnetic resonance imaging: Correlation with postoperative pain in lumbar microdiscectomy.

Magnetic resonance imaging (MRI) has been extensively used in the management of patients with a herniated lumbar disc. Nevertheless, immediate postoperative MRI has not become a standard procedure, with limited research suggesting that the findings are often similar to preoperative MRI in both symptomatic and asymptomatic patients. This study aimed to determine the benefits of immediate postoperative MRI in patients with or without postoperative symptoms and its correlation with these symptoms. A total of 172 patients who underwent lumbar spine microdiscectomy at our institution between 2014 and 2021 were included. Patients who had previous spinal surgery and lumbar fusion were excluded. Patient data were collected from medical records. MRI was performed 3 days after surgery and assessed by 2 neurosurgeons to minimize bias. Immediate postoperative MRI results showed dural sac compression or foraminal stenosis in 29 patients (16.86%), of which 10 had postoperative pain and 19 were pain free. Among the 143 patients (83.14%) without these findings on MR imaging, 38 had postoperative pain. Immediate postoperative MRI did not correlate with postoperative pain (P = .421/.357). Intraoperative bleeding and the Charlson comorbidity index (CCI) showed significant correlations with postoperative pain (P = .018 and .002, respectively). In a multivariate analysis, intraoperative blood loss and CCI independently correlated with postoperative pain (P = .001 and .001, respectively). Based on our findings, intraoperative blood loss and CCI appear to be the factors that may predict the persistence of postoperative pain, despite normal findings on MRI.

The Effect of Denosumab and Risk Factors for Recurrence in Spinal Giant Cell Tumors: A Systematic Review and Meta-Analysis.

PURPOSE: Giant cell tumors (GCTs) are common benign primary bone tumors and are well known for their locally aggressive performance and tendency to recur. The purpose of this study was to analyze the effects of denosumab and risk factors for recurrent spinal GCTs. MATERIALS AND METHODS: We searched PubMed, EMBASE, Web of Science, and Cochrane Library databases to identify differences between individuals treated with and without denosumab and risk factors for spinal GCT recurrence. Patient data, including age, sex, tumor resection range, location, denosumab use, Campanacci grade, and radiotherapy, were documented. Comparable factors were evaluated using odds ratios (ORs) and weighted mean differences (WMDs) with 95% confidence intervals (CIs). RESULTS: Sixteen studies were included. The overall incidence of spinal GCT recurrence was 29%. Campanacci grade III tumors showed better recurrence outcomes than grades I and II (OR, 16.36; 95% CI, 4.19-63.93; p<0.001). Gross total resection (OR, 0.09; 95% CI, 0.04-0.19; p<0.001), radiotherapy (OR, 0.27; 95% CI, 0.11-0.65; p=0.004), and the use of denosumab during subtotal resection (OR, 2.95; 95% CI, 1.07-8.17; p=0.04) were important factors for reducing recurrence. CONCLUSION: Clinicians must consider the effects of gross total resection, radiotherapy use, and denosumab use in cases of subtotal resection during spinal GCT treatment. So far, many researchers have used denosumab in spinal GCT, but none have clearly suggested an endpoint. Most studies, however, recommend using it for more than 6 months.

Risk Factors of Unplanned Readmission after Anterior Cervical Discectomy and Fusion: A Systematic Review and Meta-Analysis.

PURPOSE: With an increasing number of anterior cervical discectomy and fusion (ACDF) being conducted for degenerative cervical disc disease, there is a rising interest in the related quality of management and healthcare costs. Unplanned readmission after ACDF affects both the quality of management and medical expenses. This meta-analysis was performed to evaluate the risk factors of unplanned readmission after ACDF to improve the quality of management and prevent increase in healthcare costs. MATERIALS AND METHODS: We searched the databases of PubMed, EMBASE, Web of Science, and Cochrane Library to identify eligible studies using the searching terms, "readmission" and "ACDF." A total of 10 studies were included. RESULTS: Among the demographic risk factors, older age [weighted mean difference (WMD), 3.93; 95% confidence interval (CI), 2.30-5.56; p<0.001], male [odds ratio (OR), 1.23; 95% CI, 1.10-1.36; p<0.001], and private insurance (OR, 0.34; 95% CI, 0.17-0.69; p<0.001) were significantly associated with unplanned readmission. Among patient characteristics, hypertension (HTN) (OR, 2.14; 95% CI, 1.41-3.25; p<0.001), diabetes mellitus (DM) (OR, 1.59; 95% CI, 1.20-2.11; p=0.001), coronary artery disease (CAD) (OR, 2.87; 95% CI, 2.13-3.86; p<0.001), American Society of Anesthesiologists (ASA) physical status grade >2 (OR, 2.13; 95% CI, 1.68-2.72; p<0.001), and anxiety and depression (OR, 1.39; 95% CI, 1.29-1.51; p<0.001) were significantly associated with unplanned readmission. Among the perioperative factors, pulmonary complications (OR, 22.52; 95% CI, 7.21-70.41; p<0.001) was significantly associated with unplanned readmission. CONCLUSION: Male, older age, HTN, DM, CAD, ASA grade >2, anxiety and depression, pulmonary complications were significantly associated with an increased occurrence of unplanned readmission after ACDF.

Risk factors for reoperation after lumbar spine surgery in a 10-year Korean national health insurance service health examinee cohort.

Degenerative lumbar spine disease is becoming increasingly prevalent in the aging population. Surgical treatment is the standard treatment modality for intractable cases, but the reoperation rate remains high. We conducted this study to longitudinally evaluate the impact of health risk factors on the risk of lumbar spine reoperation in Koreans aged over 40 years. Subjects aged > 40 years who underwent their first lumbar spinal surgery between January 2005 and December 2008 were selected and followed up until 2015. A total of 6300 people were included. The reoperation rate during the 10-year follow-up period was 13.2% (831/6300 patients). The reoperation rate was the highest in patients in their 60 s (15.4%, P < 0.05). The reoperation rates were also significantly higher in men (vs. women: 14.7% vs. 11.7%, P < 0.05), smokers (vs. non-smokers: 15.2% vs. 12.7%, P < 0.05), alcohol drinkers (vs. non-drinkers: 14.7% vs. 12.4%, P < 0.05), and those with a higher Charlson Comorbidity Index (CCI) score (CCI 0, 11.6%; 1-2, 13.2%; and ≥ 3, 15%; P < 0.05). Among patients undergoing lumbar spine surgery, reoperation is performed in 13.2% of patients within 10 years. Male sex, age in the 60 s, alcohol use, smoking, higher Hgb and a high CCI score increased the risk of reoperation after lumbar spine operation.

A new surgical method for treating syringomyelia secondary to arachnoiditis following cervical spine surgery: the syringo-cisterna magna shunt.

PURPOSE: The 5-year postoperative failure rate of conventional shunt treatment for syringomyelia is 50%, with arachnoditis, shunt obstruction, and shunt malfunction being the most common causes. We report a new syringo-cisterna magna (SCM) shunt that allows syrinx cerebrospinal fluid (CSF) drainage normally into the cerebellomedullary cisterns through the subarachnoid space. METHODS: Between November 2012 and February 2017, six patients (mean age: 57.25 years; sex: four male and two female) received the SCM shunt. They had spinal cord injury, abscess formation after a spine operation, and cerebral meningitis-related syringomyelia (syrinx between C0 and T9), and presented sensory changes and motor weakness. Preoperatively and at 1 year postoperatively, the syrinx length and diameter were assessed using magnetic resonance imaging (MRI). Clinical outcomes were evaluated using the visual analog scale (VAS) and Japanese Orthopedic Association (JOA) scores. RESULTS: Motor weakness improved, pain subsided, and sensory disturbance resolved in all patients who returned to work within 6 weeks postoperatively. In all cases, the syrinx collapsed (length: 3.3 levels decreased; diameter: decreased from 7.90 to 4.64 mm, p = 0.046) on postoperative MRI. No patient experienced syrinx recurrence and shunt malfunction on MRI or showed spinal instability signs on plain radiography. The VAS (pre- vs post-shunt: 6.50 vs 3.83, p = 0.027) and JOA scores (pre- vs post-shunt: 10.00 vs 11.17, p = 0.167) were improved postoperatively. CONCLUSION: We developed a new shunting system allowing syrinx CSF drainage to the posterior fossa, with symptomatic improvement, minimal complications, and syrinx decrease on follow-up MRI. The SCM shunt is effective for treating syringomyelia.

Incidence, reasons, and risk factors for 30-day readmission after lumbar spine surgery for degenerative spinal disease.

This study investigated risk factors for 30-day readmission of discharged patients who had undergone lumbar spinal surgery. This retrospective, case-control study reviewed 3,933 patients discharged after elective spinal surgery for lumbar degenerative diseases from 2005 to 2012 at a university hospital. Of these patients, 102 were re-hospitalized within 30 days of discharge. Patient medical records were reviewed. The incidence of readmission within 30 days was 2.6%, and uncontrolled pain was the most common reason for readmission. In the univariate analysis, age, mental illness, the number of medical comorbidities, previous spinal surgery, fusion surgery, number of fusion levels, estimated blood loss, operation time, intensive care unit (ICU) admission, length of hospital stays, and total medical expenses were associated with a higher risk of readmission within 30 days. Multiple logistic regression analysis revealed that previous spinal surgery, operation time, ICU admission, length of hospital stays, and total medical expenses were independent risk factors for 30-day readmission. Independent risk factors for readmission were longer operation time, a previous spinal surgery, ICU admission, longer hospital stays, and higher medical expenses. Further studies controlling these risk factors could contribute to reducing readmission and thus improving the quality of care.

Diagnostic Value of Single-Photon Emission Computed Tomography/Computed Tomography Scans with Tc-99m HDP in Cervicogenic Headache.

A cervicogenic headache (CEH) is difficult to diagnose due to its varied pathology. We evaluated the usefulness of single-photon emission computed tomography/computed tomography (SPECT/CT) in diagnosing CEH and its interventional treatment. Retrospectively, 23 patients diagnosed with CEH between March 2016 to August 2018 were allocated to SPECT/CT (n = 11) and control (n = 12) groups. The SPECT/CT group was further stratified into SPECT/CT(+) and SPECT/CT(-) groups according to the presence of positive findings. Patients in the SPECT/CT group underwent an intra-articular injection at a radiologically verified lesion site, whereas those in the control group underwent third occipital nerve block. Clinical outcomes were evaluated with the visual analog scale (VAS), neck disability index (NDI), and global perceived effect (GPE) scale at baseline, and at one, three, and six months postoperatively. The SPECT/CT group showed less VAS, NDI, and GPE scores at six months postoperatively (2.91 ± 2.30 vs. 4.42 ± 1.62, p = 0.08; 38.00 ± 16.54 vs. 48.7 ± 12.40, p = 0.093; 2.00 ± 1.41 vs. 3.17 ± 1.11, p = 0.039). Successful responders at six months postoperatively were higher in the SPECT/CT(+) group than in the control group (75% vs. 0%). SPECT/CT can identify arthritic changes and accurately define therapeutic targets.

Efficacy of a Novel Annular Closure Device after Lumbar Discectomy in Korean Patients : A 24-Month Follow-Up of a Randomized Controlled Trial.

OBJECTIVE: Lumbar discectomy is an effective treatment for lumbar disc herniation (LDH); however, up to 2-18% of patients with LDH have experienced recurrent disc herniation. The purpose of this study was to evaluate the efficacy of a novel annular closure device (ACD) for preventing LDH recurrence and re-operation compared with that of conventional lumbar discectomy (CLD). METHODS: In this prospective randomized controlled trial, we compared CLD with discectomy utilizing the Barricaid® (Intrinsic Therapeutics, Inc., Woburn, MA, USA) ACD. Primary radiologic outcomes included disc height, percentage of preoperative disc height maintained, and re-herniation rates. Additional clinical outcomes included visual analog scale (VAS) scores for back and leg pain, Oswestry Disability Index (ODI) scores, and 12-item short-form health survey (SF-12) quality of life scores. Outcomes were measured at preoperation and at 1 week, 1, 3, 6, 12, and 24 months postoperation. RESULTS: Sixty patients (30 CLD, 30 ACD) were enrolled in this study. At 24-month follow-up, the disc height in the ACD group was significantly greater than that in the CLD group (11.4±1.5 vs. 10.2±1.2 mm, p=0.006). Re-herniation occurred in one patient in the ACD group versus six patients in the CLD group (χ2=4.04, p=0.044). Back and leg VAS scores, ODI scores, and SF-12 scores improved significantly in both groups compared with preoperative scores in the first 7 days following surgery and remained at significantly improved levels at a 24-month follow-up. However, no statistical difference was found between the two groups. CONCLUSION: Lumbar discectomy with the Barricaid® (Intrinsic Therapeutics, Inc.) ACD is more effective at maintaining disc height and preventing re-herniation compared with conventional discectomy. Our results suggest that adoption of ACD in lumbar discectomy can help improve the treatment outcome.

Clinical Effectiveness of Percutaneous Epidural Neuroplasty According to the Type of Single-Level Lumbar Disc Herniation : A 12-Month Follow-Up Study.

OBJECTIVE: To determine whether the outcomes of percutaneous epidural neuroplasty (PEN) are influenced by the type of lumbar disc herniation (LDH) and evaluate the effectiveness of PEN in patients with single-level LDH. METHODS: This study included 430 consecutive patients with single-level LDH who underwent PEN. Before treatment, the LDH type was categorized as bulging, protrusion, extrusion, and sequestration, while Pfirrmann grades were assigned according to imaging findings. Visual analog scale (VAS) scores for back and leg pain and success rates (Odom's criteria) were assessed at 1, 3, 6, and 12 months after treatment. RESULTS: The mean preoperative VAS scores for back and leg pain were 6.90 and 4.23, respectively; these decreased after PEN as follows : 2.25 and 1.45, respectively, at 1 month; 2.61 and 1.68, respectively, at 3 months; 2.28 and 1.48, respectively, at 6 months; and 2.88 and 1.48, respectively, at 12 months (p<0.001). The decrease in VAS scores for leg pain was significantly greater in the extrusion and sequestration groups than in the other two groups (p<0.05); there were no other significant differences among groups. More than 70% patients exhibited good or excellent 12-month outcomes according to Odom's criteria. Subsequent surgery was required for 59 patients (13.7%), with a significantly higher rate in the extrusion (25.0%) and sequestration (30.0%) groups than in the bulging (7.3%) and protrusion (13.8%) groups (p<0.05). Nevertheless, subsequent surgery was not required for >70% patients with extrusion or sequestration. Patients with Pfirrmann grades 1-3 (14.0-21.5%) showed a significantly higher rate of subsequent surgery than those with Pfirrmann grade 0 (4.9%; p<0.05). CONCLUSION: Our findings suggest that PEN is an effective treatment for back and leg pain caused by single-level LDH, with the outcomes remaining unaffected by the LDH type.

Effect of the type of electrical stimulation on spinal fusion in a rat posterolateral spinal fusion model.

BACKGROUND CONTEXT: Posterolateral fusion (PLF) with autogenous iliac bone graft is one of the most common surgical procedures for lumbar spinal disease. However, its limited success demands new biologically competent graft enhancers or substitutes. Although the use of direct current (DC) electrical stimulation has been shown to increase rate of successful spinal fusions, little is known about the effect of the type of current in DC stimulation. PURPOSE: To evaluate the effects of various DC stimulators on the strength and success rate of posterolateral fusion facilitated by using a nitinol mesh container, in rats. STUDY DESIGN: This was an experimental animal study. METHODS: A conductive, tubular nitinol mesh container was used to carry small pieces of bone grafts. The nitinol mesh container received electrical stimulation via a lead that connected the container to different types of DC stimulators. Sixty male Sprague-Dawley rats were divided into three groups (N=20 in each): a control group that underwent PLF with a nitinol container filled with autograft, a constant DC group that received a nitinol container and constant DC (100 µA), and a pulsed DC group that received a nitinol container and pulsed DC (100 µA, 100 Hz, 200 µs). The rats underwent PLF between L4 and L5, and transverse processes were grafted with bilateral iliac grafts. A stimulator was implanted subcutaneously. The rats were sacrificed 8 weeks postsurgery, and lumbar spines were removed. Spinal fusion was evaluated by microcomputed tomography, manual testing, biomechanical testing, histologic examination, and molecular analysis. RESULTS: All animals in the DC stimulation groups displayed solid fusion, whereas only 70% of control animals showed solid fusion. Radiographic images, biomechanical testing, histologic examination, and molecular analysis revealed improved fusion in the order control group

Biomechanical Analysis of Biodegradable Cervical Plates Developed for Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: In-vitro biomechanical investigation. PURPOSE: To evaluate the biomechanical effects of the degeneration of the biodegradable cervical plates developed for anterior cervical discectomy and fusion (ACDF) on fusion and adjacent levels. OVERVIEW OF LITERATURE: Biodegradable implants have been recently introduced for cervical spine surgery. However, their effectiveness and safety remains unclear. METHODS: A linear three-dimensional finite element (FE) model of the lower cervical spine, comprising the C4-C6 vertebrae was developed using computed tomography images of a 46-year-old woman. The model was validated by comparison with previous reports. Four models of ACDF were analyzed and compared: (1) a titanium plate and bone block (Tita), (2) strong biodegradable plate and bone block (PLA-4G) that represents the early state of the biodegradable plate with full strength, (3) weak biodegradable plate and bone block (PLA-1G) that represents the late state of the biodegradable plate with decreased strength, and (4) stand-alone bone block (Bloc). FE analysis was performed to investigate the relative motion and intervertebral disc stress at the surgical (C5-C6 segment) and adjacent (C4-C5 segment) levels. RESULTS: The Tita and PLA-4G models were superior to the other models in terms of higher segment stiffness, smaller relative motion, and lower bone stress at the surgical level. However, the maximal von Mises stress at the intervertebral disc at the adjacent level was significantly higher in the Tita and PLA-4G models than in the other models. The relative motion at the adjacent level was significantly lower in the PLA-1G and Bloc models than in the other models. CONCLUSIONS: The use of biodegradable plates will enhance spinal fusion in the initial stronger period and prevent adjacent segment degeneration in the later, weaker period.