Comparison of radiological and functional outcomes of conservative treatment with teriparatide and denosumab in thoracolumbar osteoporotic vertebral fracture.

Teriparatide and denosumab, anti-osteoporosis medications with different mechanisms, have been widely used in the patients with osteoporotic vertebral fracture (OVF) considered as advanced osteoporosis. Teriparatide has been shown to enhance bone formation and fracture healing in OVF, but there are still no sufficient evidences discussing about the role of denosumab in newly developed OVF. In this study, we found the similar radiological deformation and functional outcomes of conservative treatment with teriparatide and denosumab in thoracolumbar (TL) OVF, and teriparatide showed a more frequent incidence of fracture union with paravertebral bone bridge formation compared to denosumab. INTRODUCTION: Teriparatide and denosumab have been widely used to treat advanced osteoporosis and prevent subsequent fractures in patients with OVCF. Unlike teriparatide, which is considered to be effective in fracture healing, there is still no clear role and evidence for the effect of denosumab in acute OVCF. This study compared the radiological and functional outcomes of conservative treatment with teriparatide and denosumab in TL-OVF. METHODS: This retrospective study enrolled 78 women with mean age of 74.69 ± 7.66 (60-92) years diagnosed as a TL-OVF with no neurological deficits. All patients were treated conservatively with teriparatide (34 of group T, once-daily 20 µg) or denosumab (44 of group D, once-6 months 60 mg) for 6 months. We evaluated the radiological deformation (kyphotic angle, segmental vertebral kyphotic angle, and compression ratio) and the incidence of fracture union with paravertebral bone bridge formation (FUPB) and functional outcomes using the visual analog scale (VAS) and Oswestry Disability Index (ODI) at 0, 3, and 6 months. RESULTS: In the radiological deformation and functional outcomes, there were no significant differences at 0, 3, and 6 months between the two groups (P > 0.05). However, the incidence of FUPB at 6 months was higher in group T (20/34, 58.8%) compared to group D (11/44, 25.0%) (P = 0.004), and teriparatide was the most statistically significant factor for achieving FUPB (OR 4.486, P = 0.012) in multivariable logistic analysis. CONCLUSIONS: Teriparatide and denosumab, despite of their different pharmacological mechanisms, showed similar radiological deformation and functional outcomes in the conservative treatment of TL-OVF. However, teriparatide showed a significantly higher incidence of fracture union with paravertebral bone bridge formation.

Risk factors for adjacent segment disease requiring reoperation after posterior lumbar interbody fusion with screw fixation: focus on paraspinal muscle, facet joint, and disc degeneration.

PURPOSE: Adjacent segment disease (ASD) requiring revision surgery is the most serious complication that can occur in patients undergoing posterior lumbar interbody fusion (PLIF) surgery. This study aimed to determine the risk factors for surgical ASD requiring revision surgery after PLIF with screw fixation surgery. We especially focused on paraspinal muscle, facet joint, and disc degeneration. METHODS: Among the patients who underwent PLIF with screw fixation due to degenerative spinal disease from January 2010 to December 2019, patients who underwent revision surgery for the development of ASD were enrolled. To evaluate the risk factors for surgical ASD, we selected a control group. Each patient in the control group was matched by age, sex, fusion level, number of fused segments, secondary MRI follow-up interval, and follow-up duration with a patient in the surgical ASD group. The radiographic and demographic data were compared between the surgical ASD and control groups. RESULTS: There were statistically significant differences between the two groups in radiological parameters of preoperative facet degeneration, facet effusion, facet angle, and fatty degeneration of the multifidus muscle. Multivariable logistic regression analysis revealed that preoperative facet effusion (odds ratio [OR] 6.48), preoperative facet angle (OR 1.24), and progression of fatty degeneration in the multifidus muscle (OR 1.07) were significant risk factors for surgical ASD. CONCLUSIONS: Preexisting high-grade adjacent facet effusion, sagittally oriented facet joint angle, and progressive fatty degeneration of the multifidus muscle are associated with the development of surgical ASD after PLIF surgery.

Assessment of Therapeutic Responses Using a Deep Neural Network Based on 18F-FDG PET and Blood Inflammatory Markers in Pyogenic Vertebral Osteomyelitis.

Background and Objectives: This study investigated the usefulness of deep neural network (DNN) models based on 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) and blood inflammatory markers to assess the therapeutic response in pyogenic vertebral osteomyelitis (PVO). Materials and Methods: This was a retrospective study with prospectively collected data. Seventy-four patients diagnosed with PVO underwent clinical assessment for therapeutic responses based on clinical features during antibiotic therapy. The decisions of the clinical assessment were confirmed as 'Cured' or 'Non-cured'. FDG-PETs were conducted concomitantly regardless of the decision at each clinical assessment. We developed DNN models depending on the use of attributes, including C-reactive protein (CRP), erythrocyte sedimentation ratio (ESR), and maximum standardized FDG uptake values of PVO lesions (SUVmax), and we compared their performances to predict PVO remission. Results: The 126 decisions (80 'Cured' and 46 'Non-cured' patients) were randomly assigned with training and test sets (7:3). We trained DNN models using a training set and evaluated their performances for a test set. DNN model 1 had an accuracy of 76.3% and an area under the receiver operating characteristic curve (AUC) of 0.768 [95% confidence interval, 0.625-0.910] using CRP and ESR, and these values were 79% and 0.804 [0.674-0.933] for DNN model 2 using ESR and SUVmax, 86.8% and 0.851 [0.726-0.976] for DNN model 3 using CRP and SUVmax, and 89.5% and 0.902 [0.804-0.999] for DNN model 4 using ESR, CRP, and SUVmax, respectively. Conclusions: The DNN models using SUVmax showed better performances when predicting the remission of PVO compared to CRP and ESR. The best performance was obtained in the DNN model using all attributes, including CRP, ESR, and SUVmax, which may be helpful for predicting the accurate remission of PVO.

Isolated thoracic intramedullary Erdheim-Chester disease presenting with paraplegia: a case report and literature review.

BACKGROUND: Erdheim-Chester disease (ECD) is a rare, idiopathic, systemic non-Langerhans cell histiocytosis involving long bone and visceral organs. Central nervous system (CNS) involvement is uncommon and most cases develop as a part of systemic disease. We present a rare case of variant ECD as an isolated intramedullary tumor. CASE PRESENTATION: A 75-year-old female patient with a medical history of diabetes and hypertension presented with sudden-onset flaccid paraparesis for 1 day. Neurological examination revealed grade 2-3 weakness in both legs, decreased deep tendon reflex, loss of anal tone, and numbness below T4. Leg weakness deteriorated to G1 before surgery. Preoperative magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) showed an intramedullary mass lesion at T2-T4 with no systemic lesion, which was heterogeneous enhancement pattern with cord swelling and edema from C7 to T6. Gross total removal was achieved for the white-gray-colored and soft-natured intramedullary mass lesion with an ill-defined boundary. Histological finding revealed benign histiocytic proliferation with foamy histiocytes and uniform nuclei. We concluded it as an isolated intramedullary ECD. The patient showed self-standing and walkable at 18-month with no evidence of recurrence and new lesion on spine MRI and whole-body FDG-PET/CT until sudden occurrence of unknown originated thoracic cord infarction. CONCLUSIONS: We experienced an extremely rare case of isolated intramedullary ECD, which was controlled by surgical resection with no adjuvant therapy. Histological examination is the most important for final diagnosis, and careful serial follow-up after surgical resection is required to identify the recurrence and progression to systemic disease.

Radiographic predictors of clinical outcome in traumatic brain injury after decompressive craniectomy.

BACKGROUND: Primary decompressive craniectomy (DC) is considered for traumatic brain injury (TBI) patients with clinical deterioration, presenting large amounts of high-density lesions on computed tomography (CT). Postoperative CT findings may be suitable for prognostic evaluation. This study evaluated the radiographic predictors of clinical outcome and survival using pre- and postoperative CT scans of such patients. METHODS: We enrolled 150 patients with moderate to severe TBI who underwent primary DC. They were divided into two groups based on the 6-month postoperative Glasgow Outcome Scale Extended scores (1-4, unfavorable; 5-8, favorable). Radiographic parameters, including hemorrhage type, location, presence of skull fracture, midline shifting, hemispheric diameter, effacement of cisterns, parenchymal hypodensity, and craniectomy size, were reviewed. Stepwise logistic regression analysis was used to identify the prognostic factors of clinical outcome and 6-month mortality. RESULTS: Multivariable logistic regression analysis revealed that age (odds ratio [OR] = 1.09; 95% confidence interval [CI] 1.032-1.151; p = 0.002), postoperative low density (OR = 12.58; 95% CI 1.247-126.829; p = 0.032), and postoperative effacement of the ambient cistern (OR = 14.52; 95% CI 2.234-94.351; p = 0.005) and the crural cistern (OR = 4.90; 95% CI 1.359-17.678; p = 0.015) were associated with unfavorable outcomes. Postoperative effacement of the crural cistern was the strongest predictor of 6-month mortality (OR = 8.93; 95% CI 2.747-29.054; p = 0.000). CONCLUSIONS: Hemispheric hypodensity and effacement of the crural and ambient cisterns on postoperative CT after primary DC seems to associate with poor outcome in patients with TBI.

Validity of Clinical Assessment Using Clinical Symptoms and C-Reactive Protein for Therapeutic Response in Pyogenic Vertebral Osteomyelitis: Analysis Based on 18F-FDG-PET.

Backgroundand objectives: The clinical assessment of therapeutic response in pyogenic vertebral osteomyelitis (PVO) has been usually performed based on the changes of clinical symptoms and blood inflammatory markers. Recently, 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) has emerged as an alternative independent method. We analyzed the validity of the clinical assessment for detecting residual PVO based on 18F-FDG-PET. Materials and Methods: This study was conducted with 53 patients confirmed as lumbar PVO under retrospective design. All patients underwent clinical assessment using clinical symptoms and C-reactive protein (CRP) for therapeutic response after parenteral antibiotic therapy, which led to the decision of placement in the uncontrolled (group UC) or controlled (group C) group. The validity of clinical assessment was analyzed based on the cut-off values of FDG uptake for detecting residual PVO as references, which are already established in the previous literature. Results: The mean duration of parenteral antibiotic therapy and recurrence rate were 42.19 ± 15.84 (21-89) days and 9.4% (5/53), respectively. 18F-FDG-PETs were performed at 80 rounds of clinical assessment on 37.40 ± 13.15 (21-83) days of parenteral antibiotic therapy and divided: 31 into group UC and 49 into group C, according to the decisions of clinical assessment. Based on the cut-off values of FDG uptake, clinical assessment showed 48.4-58.1% of false positive for residual PVO in group UC. However, 18F-FDG-PET showed 8.2% (4/49) of false negative for residual PVO in group C, which led to recurrences. Conclusions: Clinical assessment using clinical symptoms and CRP for evaluating therapeutic response in PVO is still a useful method in terms of similar recurrence rate compared to 18F-FDG-PET. However, the high rate of false positive for residual PVO can prolong the use of unnecessary antibiotics and overall treatment period.

Antimicrobial therapy and assessing therapeutic response in culture-negative pyogenic vertebral osteomyelitis: a retrospective comparative study with culture-positive pyogenic vertebral osteomyelitis.

BACKGROUND: There are still controversies regarding the treatment and outcomes in culture-negative pyogenic vertebral osteomyelitis (PVO). The purpose of this study is to investigate the antimicrobial therapy, assessment of therapeutic response, and outcome of culture-negative PVO compared to culture-positive PVO. METHODS: A retrospective study was performed with non-surgical lumbar PVO patients. The patients were divided into two groups based on the causative bacterial identification (CN group with culture-negative PVO and CP group with culture-positive PVO). The clinical features, use of antibiotics, laboratory data, and outcomes were compared between the two groups. RESULTS: Seventy-three patients with 41 (56.2%) of the CN group and 32 (43.8%) of the CP group were enrolled. The CN group showed a shorter duration of parenteral antibiotics (45.88 ± 16.14 vs. 57.31 ± 24.39, p = 0.019) but a tendency of prolonged duration of total (parenteral + oral) antibiotics (101.17 ± 52.84 vs. 84.19 ± 50.29 days, p = 0.168). When parenteral antibiotics were discontinued or switched to oral antibiotics, the mean erythrocyte segmentation rate (ESR, normal range: < 25 mm/h), C-reactive protein (CRP, normal range: < 0.5 mg/dL) level, and visual analog scale (VAS) score of back pain were 42.86 ± 24.05 mm/h, 0.91 ± 1.18 mg/dL, and 4.05 ± 1.07, respectively, with no significant differences between the two groups. The recurrence rates of CN and CP groups were 7.3% (3/41) and 6.3% (2/32), respectively (p = 1.000). The presence of epidural abscess was the most significant factor for the identification of causative bacteria (p = 0.002), and there was no significant relationship between the use of empirical antibiotics before tissue culture and the causative bacterial identification (p = 0.194). CONCLUSIONS: The CN group required a shorter duration of parenteral antibiotics than the CP group. Discontinuation of parenteral antibiotics or changing the administration route can be considered based on the values of ESR, CRP, and VAS score of back pain. The presence of epidural abscess was the most significant factor for the identification of causative bacteria.

Giant intradural plexiform schwannoma of the lumbosacral spine - a case report and literature review.

BACKGROUND: Plexiform schwannoma (PS), variant of schwannoma, often involves multiple fascicles as plexiform neurofibroma, and is usually located superficially on the dermis and subcutaneous layers. Spinal PS is extremely rare, and there is insufficient information on its natural course and treatment strategy. We describe the clinical features and treatment of giant intradural PS at the lumbosacral spine. CASE PRESENTATION: A 66-year-old man presented with leg pain, paresthesia, and weakness for 2 years. Magnetic resonance imaging demonstrated a large mass lesion involving a continuous multi-lobulated bead-like mass and a cystic portion from L1 to S3. The lesion was iso-intense on T2-weighted images (WI), iso- to slightly low-intense on T1-WI, and heterogeneous enhancement on contrast-enhanced T1-WI. The large mass lesion had three portions, including a cystic mass at L1, continuous multi-lobulated bead-like mass with a cystic portion from L2 to S1, and multi-lobulated mass from S2 to S3, which were identified with severe adhesions with cauda equina on operative assessment. Grossly total extirpation was achieved at the lumbar spine, and remained three round shaped small masses at the lumbar area and a multi-lobulated round masses from S2 to S3 involving nerves related with motor function of the lower extremities and anal sphincter, respectively. Histological examination revealed multinodular or plexiform growth pattern composed of spindle-shaped tumor cells, which were diffusely and strongly positive for S100 protein with KI67 < 1%. There were no recurrence of preoperative symptoms and changes of the remained masses over a 2-year follow-up period. CONCLUSION: Subtotal extirpation to minimize neural deficits and close observation can be considered an appropriate treatment strategy for a giant spinal PS considering its benign prognosis and histological features, with a high risk of neurological damage during surgery.

Simultaneous 18F-FDG PET/MRI in tuberculous spondylitis: an independent method for assessing therapeutic response - case series.

BACKGROUND: 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) shows great potential for diagnosis and assessing therapeutic response of tuberculous spondylitis. Tuberculous spondylitis required long-term anti-tuberculosis (TB) medication therapy, and the optimal duration of therapy is controversial. There is still no clear way to tell when the anti-TB therapy can safely be discontinued. CASE PRESENTATION: Three patients with tuberculous spondylitis were evaluated for therapeutic response using 18F-FDG PET/magnetic resonance imaging (MRI). Clinical and hematological improvements were achieved after about 12 months of anti-TB medication therapy, and we considered whether to discontinue the therapy. There was no relapse during one year of follow-up after discontinuation of 12 months anti-TB medication based on the low maximum standardized uptake value (SUVmax) of 1.83 in one patient. However, the other two patients continued further anti-TB medication therapy based on the high SUVmax of 4.14 and 7.02, which were suspected to indicate active residual lesions in the abscess or granulation tissues. Continuous TB was confirmed by the bacterial and histological examinations. CONCLUSIONS: 18F-FDG PET/MRI has metabolic and anatomical advantages for assessing therapeutic response in TB spondylitis, and can be considered as a helpful independent and alternative method for determining the appropriate time to discontinue anti-TB medication.

Concomitant Fahr's syndrome and thoracic ossification of the posterior longitudinal ligament caused by idiopathic hypoparathyroidism - case report.

BACKGROUND: Fahr's syndrome presenting multiple and symmetric calcification of basal ganglia and cerebral cortex is rare, and idiopathic hypoparatyroidism is known as one of the causes. The relationship between ossification of posterior longitudinal ligament (OPLL) and idiopathic hypoparatyroidism is also reported in a few cases. Here, we report a patient presenting concomitant Fahr's syndrome and thoracic OPLL developed by idiopathic hypoparatyroidism. CASE PRESENTATION: 53-year-old female patient presented myelopathic sign including gait disturbance and both leg weakness (Grade 3) for 4 months after slip down, and has the history of anti-epileptic medication for several years. Magnetic resonance imaging revealed cord compression by the mixed-type OPLL from T5 to T9, and decompressive surgery was planned. Sudden onset generalized tonic-clonic seizure attack developed before the surgery. Hypocalcemia (3.7 mg/dL) with QT prolongation on electrocardiogram, hypomagnesemia (1.4 mg/dL), hyperphosphatemia (7.7 mg/dL), hypoparathyroidism, and normal range of vitamin D was noted. Brain study showed Fahr's syndrome with multiple and symmetric calcification of basal ganglia, cerebral cortex, and cerebellum. Decompressive laminectomy was performed after transient correction of hypocalcemia. The myelopathic symptoms improved to normal walking by the 14-month follow-up. The cause of hypoparathyroidism was concluded to be idiopathic. CONCLUSION: Concomitant expression of Fahr's syndrome and OPLL related with idiopathic hypoparatyroidism is very rare. However, we recommend considering the possibility of hypoparathyroidism and Fahr's syndrome when we evaluate the patients with OPLL to avoid the risks of sudden onset seizure and cardiac arrhythmia due to cerebral lesions and hypocalcemia.

Experience of surgical treatment via posterior approaches for herniated thoracic disc.

The incidence of symptomatic herniated thoracic disc (HTD) is very low. There are still no established priority in surgical approaches and guidelines for additional instrumentation with fusion. From 2007 through 2014, 38 patients (22 males and 16 females) were enrolled. The thoracolumbar region was a most common site for HTD (75.6%). The clinical characteristics of HTD based on size, location, and calcification; the factors for applying instrumentation with fusion were analyzed retrospectively. All patients were undergone surgical treatment via various posterior approaches. The additional instrumentation with fusion was performed in 14 patients (36.8%). The larger amount of facet joint resection (more than 50%) was only statistical significant factor for instrumentation (p=0.023). There were four surgical complications (10.5%). Surgical treatment via posterior approach was a reliable modality for HTD. The significant factor for applying additional instrumentation with fusion was the amount of facet joint resection.

Diagnostic and prognostic significance of preoperative evoked potential tests in degenerative cervical myelopathy.

BACKGROUND CONTEXT: Decompression surgery is a treatment option for patients with degenerative cervical myelopathy (DCM). Surgical decisions primarily depend on clinical symptoms and radiological examinations. The diagnostic and prognostic significance of evoked potential tests for surgical outcomes in patients with DCM has not been thoroughly examined. PURPOSE: To identify the diagnostic and prognostic significance of preoperative evoked potential tests in patients with DCM who underwent decompression surgery. STUDY DESIGN: This was a retrospective observational study. PATIENT SAMPLE: One hundred two consecutive patients who underwent evoked potential tests and surgical treatment between January 2016 and December 2020 in a single spine center and had a minimum follow-up of 6 months. OUTCOME MEASURES: Japanese Orthopedic Association (JOA) scores obtained preoperatively and 6 months after surgery. METHODS: This study evaluated the preoperative central motor conduction time (CMCT), somatosensory evoked potentials, and Japanese Orthopedic Association (JOA) scores obtained preoperatively and 6 months after surgery. RESULTS: Abnormal CMCT findings were observed in 94 patients (92.2%). Abnormal somatosensory evoked potentials were observed in 77 patients (75.5%). There was a statistically significant correlation between preoperative JOA score and abductor pollicis brevis (APB)-CMCT (r=-0.546, p=.001), tibialis anterior (TA)-CMCT (r=-0.517, p<.001), median nerve (MN)-SSEP (r=-0.353, p=.001), and tibial nerve (TN)-SSEP (r=-0.349, p=.003). There were significant differences in recovery rates associated with diabetes mellitus (DM), preoperative severity of myelopathy, TA-CMCT, MN-SSEP, and TN-SSEP. Stepwise multiple regression analysis showed that the major factors affecting the clinical outcomes were TN-SSEP (ß=0.327, p=.004), preoperative JOA score (ß=0.278, p=.012), and DM (ß=0.241, p=.025). CONCLUSIONS: Evoked potential testing is a functional diagnostic tool that can indicate the severity of myelopathic symptoms in patients with DCM. Additionally, preoperative TN-SSEP may have significant prognostic value in predicting postoperative clinical outcomes. Thus, preoperative evoked potential tests could be helpful for determining suitable surgical treatment candidates and forecasting postoperative prognosis.

Comparison of the Clinical Efficacy of Anabolic Agents and Bisphosphonates in the Patients With Osteoporotic Vertebral Fracture: Systematic Review and Meta-analysis of Randomized Controlled Trials.

OBJECTIVE: We investigated the clinical efficacy of anabolic agents compared with bisphosphonates (BPs) for the incidence of new osteoporotic vertebral fracture (OVF) and fracture healing of OVF in the patients with OVF via meta-analyses of randomized controlled trials (RCTs). METHODS: Electronic databases, including PubMed, Embase, and Cochrane Library were searched for published RCTs till December 2022. The RCTs that recruited participants with osteoporosis at high-/very high-risk of fracture (a history of osteoporotic vertebral or hip fracture) or fresh OVF were included in this study. We assessed the risk of bias on every included RCTs, estimated relative risk (RR) for the incidence of new OVF and fracture healing of OVF, and overall certainty of evidence. Meta-analyses were performed by Cochrane review manager (RevMan) ver. 5.3. Cochrane risk of bias 2.0 and GRADEpro/GDT were applied for evaluating methodological quality and overall certainty of evidence, respectively. RESULTS: Five hundred eighteen studies were screened, and finally 6 eligible RCTs were included in the analysis. In the patients with prevalent OVF, anabolic agents significantly reduced the incidence of new OVF (teriparatide and romosozumab vs. alendronate and risedronate [RR, 0.57; 95% confidence interval, 0.45-0.71; p < 0.00001; high-certainty of evidence]; teriparatide vs. risedronate [RR, 0.50; 95% confidence interval, 0.37-0.68; p < 0.0001; high-certainty of evidence]). However, there was no evidence of teriparatide compared to alendronate in fracture healing of OVF (RR, 1.23; 95% confidence interval, 0.95-1.60; p = 0.12; low-certainty of evidence). CONCLUSION: In the patients with prevalent OVF, anabolic agents showed a significant superiority for preventing new OVF than BPs, with no significant evidence for promoting fracture healing of OVF. However, considering small number of RCTs in this study, additional studies with large-scale data are required to obtain more robust evidences.

Generation of synthetic PET/MR fusion images from MR images using a combination of generative adversarial networks and conditional denoising diffusion probabilistic models based on simultaneous 18F-FDG PET/MR image data of pyogenic spondylodiscitis.

BACKGROUND CONTEXT: Cross-modality image generation from magnetic resonance (MR) to positron emission tomography (PET) using the generative model can be expected to have complementary effects by addressing the limitations and maximizing the advantages inherent in each modality. PURPOSE: This study aims to generate synthetic PET/MR fusion images from MR images using a combination of generative adversarial networks (GANs) and conditional denoising diffusion probabilistic models (cDDPMs) based on simultaneous 18F-fluorodeoxyglucose (18F-FDG) PET/MR image data. STUDY DESIGN: Retrospective study with prospectively collected clinical and radiological data. PATIENT SAMPLE: This study included 94 patients (60 men and 34 women) with thoraco-lumbar pyogenic spondylodiscitis (PSD) from February 2017 to January 2020 in a single tertiary institution. OUTCOME MEASURES: Quantitative and qualitative image similarity were analyzed between the real and synthetic PET/ T2-weighted fat saturation MR (T2FS) fusion images on the test data set. METHODS: We used paired spinal sagittal T2FS and PET/T2FS fusion images of simultaneous 18F-FDG PET/MR imaging examination in patients with PSD, which were employed to generate synthetic PET/T2FS fusion images from T2FS images using a combination of Pix2Pix (U-Net generator + Least Squares GANs discriminator) and cDDPMs algorithms. In the analyses of image similarity between the real and synthetic PET/T2FS fusion images, we adopted the values of mean peak signal to noise ratio (PSNR), mean structural similarity measurement (SSIM), mean absolute error (MAE), and mean squared error (MSE) for quantitative analysis, while the discrimination accuracy by three spine surgeons was applied for qualitative analysis. RESULTS: Total of 2,082 pairs of T2FS and PET/T2FS fusion images were obtained from 172 examinations on 94 patients, which were randomly assigned to training, validation, and test data sets in 8:1:1 ratio (1664, 209, and 209 pairs). The quantitative analysis revealed PSNR of 30.634 ± 3.437, SSIM of 0.910 ± 0.067, MAE of 0.017 ± 0.008, and MSE of 0.001 ± 0.001, respectively. The values of PSNR, MAE, and MSE significantly decreased as FDG uptake increased in real PET/T2FS fusion image, with no significant correlation on SSIM. In the qualitative analysis, the overall discrimination accuracy between real and synthetic PET/T2FS fusion images was 47.4%. CONCLUSIONS: The combination of Pix2Pix and cDDPMs demonstrated the potential for cross-modal image generation from MR to PET images, with reliable quantitative and qualitative image similarities.

Using Machine Learning Models to Identify Factors Associated With 30-Day Readmissions After Posterior Cervical Fusions: A Longitudinal Cohort Study.

OBJECTIVE: Readmission rates after posterior cervical fusion (PCF) significantly impact patients and healthcare, with complication rates at 15%-25% and up to 12% 90-day readmission rates. In this study, we aim to test whether machine learning (ML) models that capture interfactorial interactions outperform traditional logistic regression (LR) in identifying readmission-associated factors. METHODS: The Optum Clinformatics Data Mart database was used to identify patients who underwent PCF between 2004-2017. To determine factors associated with 30-day readmissions, 5 ML models were generated and evaluated, including a multivariate LR (MLR) model. Then, the best-performing model, Gradient Boosting Machine (GBM), was compared to the LACE (Length patient stay in the hospital, Acuity of admission of patient in the hospital, Comorbidity, and Emergency visit) index regarding potential cost savings from algorithm implementation. RESULTS: This study included 4,130 patients, 874 of which were readmitted within 30 days. When analyzed and scaled, we found that patient discharge status, comorbidities, and number of procedure codes were factors that influenced MLR, while patient discharge status, billed admission charge, and length of stay influenced the GBM model. The GBM model significantly outperformed MLR in predicting unplanned readmissions (mean area under the receiver operating characteristic curve, 0.846 vs. 0.829; p < 0.001), while also projecting an average cost savings of 50% more than the LACE index. CONCLUSION: Five models (GBM, XGBoost [extreme gradient boosting], RF [random forest], LASSO [least absolute shrinkage and selection operator], and MLR) were evaluated, among which, the GBM model exhibited superior predictive performance, robustness, and accuracy. Factors associated with readmissions impact LR and GBM models differently, suggesting that these models can be used complementarily. When analyzing PCF procedures, the GBM model resulted in greater predictive performance and was associated with higher theoretical cost savings for readmissions associated with PCF complications.

Analysis of Clinical Factors Associated with Medical Burden and Functional Status in Pyogenic Spine Infection.

BACKGROUND AND PURPOSE: Pyogenic spinal infection (PSI) has recently been on the rise due to aging and increasing degenerative spinal disease related procedures. PSI requires long-term antibiotic treatment and is followed by sustained functional disability even after successful treatment. This study aimed to analyze the clinical factors associated with medical burden and functional status of PSI. METHODS: This retrospective study involved patients with non-postoperative PSI of thoraco-lumbo-sacral area in a single tertiary hospital. The length/cost of hospitalization with an antibiotic therapy and severity of back pain using the short form 36 (SF-36) were defined as the medical burden and functional status, respectively. We analyzed the clinical factors associated with medical burden and functional status. RESULTS: We enrolled 142 patients (91 males and 51 females). The length and cost of hospitalization were 55.56 ± 27.09 (7-172) days and $14,070.17 ± 9289.39 (1611.87-48,722.35), respectively. A recurrence rate of 7.7% (11/142) and significant improvement of SF-36 at six months after completion of antibiotic treatment were noted (p < 0.05). Procedure-related (OR 2.702), C-reactive protein (CRP; OR 1.062), bacteremia (OR 4.966), additional surgical treatment (OR 6.524), recurrence (OR 12.453), and paraspinal abscess (OR 5.965) for above-average length of hospitalization were observed; female (OR 4.438), CRP (OR 1.071), bacteremia (OR 4.647), additional surgical treatment (OR 6.737), recurrence (OR 22.543), and extent of lesion (OR 1.431) for above-average cost of hospitalization; leg weakness (OR 15.966), white blood cell (WBC; OR 1.116), Charlson's comorbidity index (CCI, OR 1.485), and identification of causative bacteria (OR 2.913) for below-average initial SF-36 were observed; leg weakness (OR 7.975) and WBC (OR 1.094) for below-average 6-month SF-36 were the statistically significant clinical factors in the multivariable logistic regression analysis (p < 0.05). CONCLUSION: Recurrence and leg weakness were identified as the most important clinical factors for medical burden and functional status in PSI, respectively. We think that it is necessary to actively suppress recurrence and manage neurological deficits for decreasing medical burden and achieving favorable functional outcome in the treatment of PSI.

Probabilistic graphical modelling using Bayesian networks for predicting clinical outcome after posterior decompression in patients with degenerative cervical myelopathy.

BACKGROUND: Probabilistic graphical modelling (PGM) can be used to predict risk at the individual patient level and show multiple outcomes and exposures in a single model. OBJECTIVE: To develop PGM for the prediction of clinical outcome in patients with degenerative cervical myelopathy (DCM) after posterior decompression and to use PGM to identify causal predictors of the outcome. METHODS: We included data from 59 patients who had undergone cervical posterior decompression for DCM. The candidate predictive parameters were age, sex, body mass index, trauma history, symptom duration, preoperative and last Japanese Orthopaedic Association (JOA) scores, gait impairment, claudication, bladder dysfunction, Nurick grade, American Spinal Injury Association (ASIA) grade, smoking, diabetes mellitus, cardiopulmonary disorders, hypertension, stroke, Parkinson's disease, dementia, psychiatric disorders, arthritis, ossification of the posterior longitudinal ligament, cord signal change, postoperative kyphosis and the cord compression ratio. RESULTS: In regression analyses, preoperative JOA (PreJOA) score, presence of a psychiatric disorder, and ASIA grade were identified as significant factors associated with the last JOS score. Dementia, sex, PreJOA score and gait impairment were causal factors in the PGM. Sex, dementia and PreJOA score were direct causal factors related to the last follow-up JOA (LastJOA) score. Being female, having dementia, and having a low PreJOA score were significantly related to having a low LastJOA score. CONCLUSIONS: The causal predictors of surgical outcome for DCM were sex, dementia and PreJOA score. Therefore, PGM may be a useful personalized medicine tool for predicting the outcome of patients with DCM.

Sex, dementia and preoperative neurological status are causal factors contributing to the postoperative outcome of patients with degenerative cervical myelopathy.The Bayesian network (BN) structure may be useful for predicting the probability for clinical outcomes for each patient who undergoes posterior decompressive surgery.The BN structure may provide a useful model in the current era of personalized medicine.

An unusual penetrating injury of the back: retroperitoneal hematoma from a glass stabbing injury: a case report.

In stab injury of the back visceral or vascular injuries are more uncommon than anterior abdominal stab injuries. The authors report the case of a 52-year-old man who presented to the emergency center with glass fragments lodged in his back after falling on a glass door on his back. On a retroperitoneal computed tomography (CT) scan, two foreign bodies were detected in left paraspinal and psoas muscles. Furthermore, hematoma with active bleeding was seen in the retroperitoneal cavity. He was referred to a general surgeon for retroperitoneal active bleeding, but emergency laparotomy was not deemed necessary considering the patient's stable condition in terms of vital signs, the level of hemoglobin, and the amount of bleeding. Therefore, we performed conservative treatment, such as packed cell transfusion and back compression, after removing the glass fragment through the posterior approach. The paravertebral muscle was dissected through the open wound, the tip of the piece of glass was accessible. The piece of glass was carefully removed, and there was no active bleeding. The postoperative CT scan showed continued active bleeding and increased retroperitoneal hematoma, but the patient's vital signs were stable. Conservative treatment was administered continuously, a follow-up CT scan taken a month later showed hematoma resolution and no more dye leakage. If the patient's vital signs are stable and the patient is neurologically intact, conservative treatment may be prioritized without laparotomy.

Paraspinal muscle fatty degeneration as a predictor of progressive vertebral collapse in osteoporotic vertebral compression fractures.

BACKGROUND CONTEXT: Most osteoporotic vertebral compression fractures (OVCFs) are treated conservatively; however, in some patients, progressive vertebral body collapse leads to spinal deformity and cord compression. These complications are strongly associated with impaired performance activities of daily living and a poor quality of life. PURPOSE: To identify the role of the paraspinal muscle as a risk factor for progressive vertebral body collapse in patients with OVCF. STUDY DESIGN: This was a retrospective observational study. PATIENT SAMPLE: Fifty-five consecutive patients with OVCF who were treated conservatively from January 2018 to June 2020 in a single spine center and had a minimum follow-up of 6 months. OUTCOME MEASURES: A lateral plain radiograph in a neutral posture was taken when the patient was first diagnosed and at 1, 3, and 6 months after the first diagnosis. Vertebral height was measured at the point of maximal collapse of the affected vertebral body; vertebral collapse (%) was also measured. The cross-sectional area (CSA) and fatty degeneration of the paraspinal muscle were measured using the open-source software Image J. The visual analogue scale (VAS) scores were collected at the time of initial fracture diagnosis and at 1, 3, and 6 months. METHODS: The clinical and radiological data were analyzed. In the L4-5 intervertebral disc level, axial T2-weighted magnetic resonance imaging was used to measure the CSA and fatty degeneration of the paraspinal muscles. Correlation and multiple regression analyses were performed to analyze the risk factors associated with progressive vertebral body collapse. RESULTS: The vertebral collapse difference was strongly associated with paraspinal muscle fatty degeneration (r=0.684, p=.000) and body mass index (r=0.300, p=.026). Multiple linear regression analysis demonstrated that the risk factor for progression of vertebral collapse was paraspinal muscle fatty degeneration (ß=0.724, p=.000). There was a statistically significant correlation between the progression in vertebral collapse and VAS score at 3 (r=0.402, p=.002) and 6 months (r=0.604, p=.000). CONCLUSIONS: In patients with OVCF, fatty degeneration of the paraspinal muscle was a predictive factor for progressive vertebral body collapse. This study suggests that more attention should be paid to patients with paraspinal sarcopenia among those with OVCFs.

Non-operative Treatment of Osteoporotic Thoracolumbar Extension-distraction Fracture Using Teriparatide in Elderly Female Patient with Severe Osteoporosis under Inoperable Condition: A Case Report.

Vertebral extension-distraction fractures are a type of unstable fracture and require surgical stabilization with instrumentation. Unfortunately, in elderly patients with severe osteoporosis, poor bone quality can be related to postoperative pseudo-arthrosis and instability. Teriparatide is known as an effective anabolic agent for bone healing, union, and managing osteoporosis. In this report, we describe a rare case of extension-distraction thoracolumbar fractures in 86-year-old female patient with severe osteoporosis, which was treated conservatively. The patient was inoperable due to the presence of concomitant cardiopulmonary problems and the patients' old age. She had poor bone quality on bone mineral densitometry (-6.7, lumbar spine) but no neurologic deficits. As conservative treatment, bedrest and pain control were first performed for three weeks along with the use of teriparatide for 6-month and supplementation of calcium and vitamin D. Afterwards, sitting and standing with wearable orthoses were gradually implemented. After 1 year, the patient achieved bone fusion and was able to walk by herself, and there was radiological correction of the initial segmental lordotic curvature and disappearance of the intravertebral gap caused by the extension-distraction fracture.