Computed tomographic and magnetic resonance imaging features of canine cervical epidural dirofilariasis.

An 8-year-old neutered male Maltese dog presented with a month-long history of progressive nonambulatory tetraparesis. MRI revealed a well-defined, centrally nonenhanced, T1-weighted hypointense, extradural structure located in the vertebral canal at the level of the C5 vertebral body. CT demonstrated a hypoattenuating, space-occupying structure in the same area. Surgery revealed a long, narrow parasite in the epidural space. An adult Dirofilaria immitis was confirmed by multiplex polymerase chain reaction (PCR) assay. This is a novel report describing the MRI and CT features of cervical epidural dirofilariasis in a dog.

Deep learning-based detection of lumbar spinal canal stenosis using convolutional neural networks.

BACKGROUND CONTEXT: Lumbar spinal canal stenosis (LSCS) is the most common spinal degenerative disorder in elderly people and usually first seen by primary care physicians or orthopedic surgeons who are not spine surgery specialists. Magnetic resonance imaging (MRI) is useful in the diagnosis of LSCS, but the equipment is often not available or difficult to read. LSCS patients with progressive neurologic deficits have difficulty with recovery if surgical treatment is delayed. So, early diagnosis and determination of appropriate surgical indications are crucial in the treatment of LSCS. Convolutional neural networks (CNNs), a type of deep learning, offers significant advantages for image recognition and classification, and work well with radiographs, which can be easily taken at any facility. PURPOSE: Our purpose was to develop an algorithm to diagnose the presence or absence of LSCS requiring surgery from plain radiographs using CNNs. STUDY DESIGN: Retrospective analysis of consecutive, nonrandomized series of patients at a single institution. PATIENT SAMPLE: Data of 150 patients who underwent surgery for LSCS, including degenerative spondylolisthesis, at a single institution from January 2022 to August 2022, were collected. Additionally, 25 patients who underwent surgery at 2 other hospitals were included for extra external validation. OUTCOME MEASURES: In annotation 1, the area under the curve (AUC) computed from the receiver operating characteristic (ROC) curve, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, positive likelihood ratio (PLR), and negative likelihood ratio (NLR) were calculated. In annotation 2, correlation coefficients were used. METHODS: Four intervertebral levels from L1/2 to L4/5 were extracted as region of interest from lateral plain lumbar spine radiographs totaling 600 images were obtained. Based on the date of surgery, 500 images derived from the first 125 cases were used for internal validation, and 100 images from the subsequent 25 cases used for external validation. Additionally, 100 images from other hospitals were used for extra external validation. In annotation 1, binary classification of operative and nonoperative levels was used, and in annotation 2, the spinal canal area measured on axial MRI was labeled as the output layer. For internal validation, the 500 images were divided into each 5 dataset on per-patient basis and 5-fold cross-validation was performed. Five trained models were registered in the external validation prediction performance. Grad-CAM was used to visualize area with the high features extracted by CNNs. RESULTS: In internal validation, the AUC and accuracy for annotation 1 ranged between 0.85-0.89 and 79-83%, respectively, and the correlation coefficients for annotation 2 ranged between 0.53 and 0.64 (all p<.01). In external validation, the AUC and accuracy for annotation 1 were 0.90 and 82%, respectively, and the correlation coefficient for annotation 2 was 0.69, using 5 trained CNN models. In the extra external validation, the AUC and accuracy for annotation 1 were 0.89 and 84%, respectively, and the correlation coefficient for annotation 2 was 0.56. Grad-CAM showed high feature density in the intervertebral joints and posterior intervertebral discs. CONCLUSIONS: This technology automatically detects LSCS from plain lumbar spine radiographs, making it possible for medical facilities without MRI or nonspecialists to diagnose LSCS, suggesting the possibility of eliminating delays in the diagnosis and treatment of LSCS that require early treatment.

Predictors of Patient Dissatisfaction after Lumbar Spinal Canal Stenosis Surgery: A Multicenter Retrospective Study.

Introduction: Recently, patient satisfaction has gained prominence as a crucial measure for ensuring patient-centered care. Furthermore, patient satisfaction after lumbar spinal canal stenosis (LCS) surgery is an important metric for physician's decision of surgical indication and informed consent to patient. This study aimed to elucidate how patient satisfaction changed after LCS surgery to identify factors that predict patient dissatisfaction. Methods: We retrospectively reviewed time-course data of patients aged ≥40 years who underwent LCS surgery at multiple hospitals. The participants completed the Zurich Claudication Questionnaire (ZCQ) and the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) before surgery and then 6 months and 1 year postsurgery. Patient satisfaction was categorized according to the postoperative score of the satisfaction domain of the ZCQ: satisfied, score ≤2.0; moderately satisfied, 2.0< score ≤2.5; and dissatisfied, score >2.5. Results: The study enrolled 241 patients. Our data indicated a satisfaction rate of around 70% at 6 months and then again 1 year after LCS surgery. Among those who were dissatisfied 6 months after LCS surgery, 47.6% were more satisfied 1 year postsurgery. Furthermore, 86.2% of those who were satisfied 6 months after LCS surgery remained satisfied at 1 year. Multivariable analysis revealed that age (relative risk, 0.5; 95% confidence interval, 0.2-0.8) and preoperative score of psychological disorders on the JOABPEQ (relative risk, 0.2; 95% confidence interval, 0.03-0.08) were significantly associated with LCS surgery dissatisfaction. In addition, the receiver operating characteristic curve analysis revealed that the cutoff value for the preoperative score of psychological disorder of the JOABPEQ was estimated at 40 for LCS surgery dissatisfaction. Conclusions: Age and psychological disorders were identified as significant predictors of dissatisfaction, with a JOABPEQ cutoff value providing potential clinical applicability.

Minimally Invasive Trans-sacral Canal Plasty for Lumbar Canal Stenosis.

Objective The elderly population is increasing in Japan. Along with the increase in the elderly population, the number of patients with lumbar degenerative diseases is also on the rise. In general, elderly patients tend to have more complications and are at higher risk for surgery. Many elderly people suffer from lumbar degenerative disease. We reviewed our initial experience with trans-sacral canal plasty (TSCP) for patients with lumbar spinal canal stenosis and examined the pertinent literature for this report. Methods An analytical observational study was performed on 120 patients with lumbar spinal canal stenosis who underwent TSCP at our single institution from March 2019 to October 2021. These patients had leg pain and/or lower back pain due to degenerative lumbar disease. Patients who had coagulation abnormality, pregnancy, contrast allergy, pyogenic spondylitis, or spinal metastasis were excluded. Results Immediately after TSCP, the average Visual Analog Scale (VAS) score for back pain improved from 58.2 to 29.3, and for leg pain from 72.0 to 31.3. Two years after TSCP, the average VAS score for back pain increased slightly and the average score for leg pain remained almost the same. Additional surgery was performed in 37 of 120 (31%) patients who underwent TSCP. The additional surgery group had significantly worse back pain at one and three months postoperatively than the conservative treatment group. The additional surgery group had significantly worse leg pain immediately after TSCP and at one and three months postoperatively than the conservative treatment group. Logistic regression analysis demonstrated that a decreased spinal canal area (OR 0.986, p = 0.039) was associated with additional surgery. Conclusions We reviewed the outcomes of TSCP at our hospital. The average VAS score for back pain and leg pain improved. However, 31% of patients who underwent TSCP required additional surgery. It was found that the spinal canal area was a major factor in the need for additional surgery.

Effects of circulating inflammatory proteins on spinal degenerative diseases: Evidence from genetic correlations and Mendelian randomization study.

Background: Numerous investigations have suggested links between circulating inflammatory proteins (CIPs) and spinal degenerative diseases (SDDs), but causality has not been proven. This study used Mendelian randomization (MR) to investigate the causal associations between 91 CIPs and cervical spondylosis (CS), prolapsed disc/slipped disc (PD/SD), spinal canal stenosis (SCS), and spondylolisthesis/spondylolysis. Methods: Genetic variants data for CIPs and SDDs were obtained from the genome-wide association studies (GWAS) database. We used inverse variance weighted (IVW) as the primary method, analyzing the validity and robustness of the results through pleiotropy and heterogeneity tests and performing reverse MR analysis to test for reverse causality. Results: The IVW results with Bonferroni correction indicated that beta-nerve growth factor (ß-NGF), C-X-C motif chemokine 6 (CXCL6), and interleukin-6 (IL-6) can increase the risk of CS. Fibroblast growth factor 19 (FGF19), sulfotransferase 1A1 (SULT1A1), and tumor necrosis factor-beta (TNF-ß) can increase PD/SD risk, whereas urokinase-type plasminogen activator (u-PA) can decrease the risk of PD/SD. FGF19 and TNF can increase SCS risk. STAM binding protein (STAMBP) and T-cell surface glycoprotein CD6 isoform (CD6 isoform) can increase the risk of spondylolisthesis/spondylolysis, whereas monocyte chemoattractant protein 2 (MCP2) and latency-associated peptide transforming growth factor beta 1 (LAP-TGF-ß1) can decrease spondylolisthesis/spondylolysis risk. Conclusions: MR analysis indicated the causal associations between multiple genetically predicted CIPs and the risk of four SDDs (CS, PD/SD, SCS, and spondylolisthesis/spondylolysis). This study provides reliable genetic evidence for in-depth exploration of the involvement of CIPs in the pathogenic mechanism of SDDs and provides novel potential targets for SDDs.

Steel bar penetrating cervical spinal canal without neurological injury: A case report.

BACKGROUND: We report a rare case of cervical spinal canal penetrating trauma and review the relevant literatures. CASE SUMMARY: A 58-year-old male patient was admitted to the emergency department with a steel bar penetrating the neck, without signs of neurological deficit. Computed tomography (CT) demonstrated that the steel bar had penetrated the cervical spinal canal at the C6-7 level, causing C6 and C7 vertebral body fracture, C6 left lamina fracture, left facet joint fracture, and penetration of the cervical spinal cord. The steel bar was successfully removed through an open surgical procedure by a multidisciplinary team. During the surgery, we found that the cervical vertebra, cervical spinal canal and cervical spinal cord were all severely injured. Postoperative CT demonstrated severe penetration of the cervical spinal canal but the patient returned to a fully functional level without any neurological deficits. CONCLUSION: Even with a serious cervical spinal canal penetrating trauma, the patient could resume normal work and life after appropriate treatment.

A Three-Dimensional Morphological Assessment for Evaluating Pre- and Postsurgery in Cervical Laminoplasty.

OBJECTIVE: The efficacy of medical treatments and the changes in radiologic imaging before and after treatment have consistently remained pivotal factors. This is particularly critical for surgical procedures, where precise evaluation of disparities pre and postsurgery or the accuracy of implantation is paramount. Based on three-dimensional morphological interests, we provide an automatic quantification evaluation method that delivers an evident base for assessing the outcomes of a widely employed surgical technique, cervical laminoplasty. METHODS: The sample study included patients who underwent cervical laminoplasty for cervical spondylotic myelopathy/ossification of the longitudinal ligament. We present a superimposition method that facilitates a unique and precise assessment between pre and postsurgery. The degree of expansion was evaluated by the canal volume increase and canal expansion rate after surgery. RESULTS: There were 31 patients with 112 vertebral segments measured. The target cervical's pre and postoperative canal areas were 122.63 ± 30.34 and 196.50 ± 37.10 mm2, respectively (P < 0.001). The average cervical canal expansion rate was 64.42%. The expansion effect of C5 cervical laminoplasty was the maximum (71.01%), and the canal volume of other segments expanded by approximately 60%. The functional outcomes demonstrated significant improvements in symptoms. CONCLUSIONS: The quantification evaluation method can be utilized for any morphology changes before and after laminoplasty, as it does not lead to errors or variations from different inspection machines or human factors. The automatic method delivers an evident base for assessing the outcomes of a widely employed surgical technique.

Focal compression of the cervical spinal cord alone does not indicate high risk of neurological deterioration in patients with a diagnosis of mild degenerative cervical myelopathy.

Degenerative Cervical Myelopathy (DCM) is the functional derangement of the spinal cord resulting from vertebral column spondylotic degeneration. Typical neurological symptoms of DCM include gait imbalance, hand/arm numbness, and upper extremity dexterity loss. Greater spinal cord compression is believed to lead to a higher rate of neurological deterioration, although clinical experience suggests a more complex mechanism involving spinal canal diameter (SCD). In this study, we utilized machine learning clustering to understand the relationship between SCD and different patterns of cord compression (i.e. compression at one disc level, two disc levels, etc.) to identify patient groups at risk of neurological deterioration. 124 MRI scans from 51 non-operative DCM patients were assessed through manual scoring of cord compression and SCD measurements. Dimensionality reduction techniques and k-means clustering established patient groups that were then defined with their unique risk criteria. We found that the compression pattern is unimportant at SCD extremes (≤14.5 mm or > 15.75 mm). Otherwise, severe spinal cord compression at two disc levels increases deterioration likelihood. Notably, if SCD is normal and cord compression is not severe at multiple levels, deterioration likelihood is relatively reduced, even if the spinal cord is experiencing compression. We elucidated five patient groups with their associated risks of deterioration, according to both SCD range and cord compression pattern. Overall, SCD and focal cord compression alone do not reliably predict an increased risk of neurological deterioration. Instead, the specific combination of narrow SCD with multi-level focal cord compression increases the likelihood of neurological deterioration in mild DCM patients.

Comparing the Efficacy of Transforaminal and Caudal Epidural Injections of Calcitonin in Treating Degenerative Spinal Canal Stenosis: A Double-Blind Randomized Clinical Trial.

Background: Lumbar spinal stenosis (LSS) is the most common indication for lumbar surgery in elderly patients. Epidural injections of calcitonin are effective in managing LSS. Objectives: This study aimed to compare the efficacy of transforaminal and caudal injections of calcitonin in patients with LSS. Methods: In this double-blind randomized clinical trial, LSS patients were divided into two equal groups (N = 20). The first group received 50 IU (international units) of calcitonin via caudal epidural injection (CEI), and the second group received 50 IU of calcitonin via transforaminal epidural injection (TEI). The Visual Analogue Scale (VAS) and Oswestry Low Back Pain Disability Questionnaire (ODI) were used to assess the patient's pain and ability to stand, respectively. Visual Analogue Scale and ODI scores were recorded and analyzed. Results: The results showed that caudal and TEIs of calcitonin significantly improved pain and ability to stand during follow-up compared to before intervention (P < 0.05). Additionally, CEI of calcitonin after 6 months significantly reduced pain in LSS patients compared to TEI of calcitonin (P < 0.05). However, no significant difference was observed between the two epidural injection techniques in improving the patient's ability to stand (P > 0.05). Conclusions: The results of the study indicate that epidural injection of calcitonin in long-term follow-up (6 months) had a significant effect on improving pain intensity and mobility in patients with LSS, and its effect on pain in the TEI method was significantly greater than that in the CEI method.

Evidence-based commentary on the diagnosis, management, and further research of degenerative cervical spinal cord compression in the absence of clinical symptoms of myelopathy.

Degenerative cervical myelopathy (DCM) represents the final consequence of a series of degenerative changes in the cervical spine, resulting in cervical spinal canal stenosis and mechanical stress on the cervical spinal cord. This process leads to subsequent pathophysiological processes in the spinal cord tissues. The primary mechanism of injury is degenerative compression of the cervical spinal cord, detectable by magnetic resonance imaging (MRI), serving as a hallmark for diagnosing DCM. However, the relative resilience of the cervical spinal cord to mechanical compression leads to clinical-radiological discordance, i.e., some individuals may exhibit MRI findings of DCC without the clinical signs and symptoms of myelopathy. This degenerative compression of the cervical spinal cord without clinical signs of myelopathy, potentially serving as a precursor to the development of DCM, remains a somewhat controversial topic. In this review article, we elaborate on and provide commentary on the terminology, epidemiology, natural course, diagnosis, predictive value, risks, and practical management of this condition-all of which are subjects of ongoing debate.

Radiation Exposure During Lumbar Interbody Fusion Surgery Can Be Reduced by Using a Three-Dimensional Patient-Specific Template Guide.

BACKGROUND: The use of posterior lumber interbody fusion (PLIF) using cortical bone trajectory (CBT) with a patient-specific 3D template guide is increasingly widespread. To our knowledge, no studies have extensively evaluated the reduction of radiation exposure when using patient-specific drill template guides. The purpose of this study is to compare the intra-operative radiation dose and surgeon's exposure to radiation in CBT-PLIF when using a patient-specific drill guide with that in traditional minimally invasive (MIS)-PLIF. METHODS: In this observational study, we retrospectively compared data from five patients who were treated with single-level CBT-PLIF using a patient-specific drill guide (G group) and five patients who were treated with single-level traditional MIS-PLIF (M group). We compared the surgical time, surgeon's exposure to radiation, and intra-operative radiation time and dose between the two groups of patients. RESULTS: The mean age of the patients was 67.0 years in the M group and 74.2 years in the G group. The average surgical time was 242.8 min in the M group and 189.6 min in the G group (p = 0.020). The surgeon's exposure to radiation was 373.7 µSv in the M group and 81.75 µSv in the G group at chest level outside the protector (p = 0.00092); 42.0 µSv (M group) and 3.6 µSv (G group) at chest level inside the protector (p = 0.0000062); and 4.33 µSv (M group) and 1.20 µSv (G group) at the buttocks of the surgeon (p = 0.0013). Radiation time was 269.8 s (M group) and 56.6 s (G group) (p = 0.0097), and radiation dose was 153.7 mGy (M group) and 30.42 mGy (G group) (p = 0.00057). CONCLUSION: The patient-specific drill template guide is an invaluable tool that facilitates the safe insertion of CBT screws with a low radiation dose from the outset.

Morphometric Evaluation of Thoracolumbar Spinal Canal and Cord by Magnetic Resonance Imaging in Normal Small-Breed Dogs.

Thoracolumbar intervertebral disc disease (IVDD) is the most common cause of spinal injury in dogs. MRI has been considered the gold standard for neurologic diagnosis, but studies focusing on the thoracolumbar spinal canal and spinal cord using MRI in small-breed dogs are limited. Therefore, this study aimed to establish an MRI reference range for the spinal cord and canal measurements (height, width, cord-to-canal ratio of height, width, cross-sectional area (CSA)) of each intervertebral disc level from T11 to L5 (total of seven levels) on transverse T2-weighted images in normal small-breed dogs. We hypothesized that the spinal cord and spinal canal measurements might vary according to the body weight and age. The width and height of the spinal cord and canal increased as the body weight increased at all levels (p < 0.05). The cord-to-canal ratio of the width showed a negative correlation to the body weight at all levels. The cord-to-canal ratio of the height did not show any correlation to the body weight at all levels. All measurements (height, width, cord-to-canal ratio of height, width, CSA) did not show any statistical correlation between the groups subdivided by age. These measurements could serve as a morphometric baseline for thoracolumbar spinal diseases and clinical research in small-breed dogs.

Acquired Simple Bone Cyst Associated With Lumbar Spinal Canal Stenosis Progression: A Case Report.

A simple bone cyst (SBC) in the posterior lumbar bone structure is very rare. Here, we report a case of SBC at the L5 lumbar lamina with venous obstruction associated with ligamentum flavum thickening. A 59-year-old woman presented with intermittent claudication due to low back pain and bilateral sciatica. A lumbar MRI showed L4-5 lumbar spinal canal stenosis and a T2-weighted image hyperintense lesion in the L5 lamina. Imaging four years earlier showed no lesions in the L5 lamina. Her symptoms improved after lumbar decompression surgery. The L5 lamina lesion was SBC, leading to a diagnosis of venous infarction. The involvement of neovascularization in the mechanism of degenerative hypertrophy in the ligamentum flavum was suggested. In this case, increased venous perfusion and venous obstruction were involved in the formation of the bone cyst.

The Impact of Frailty on Surgical Outcome of Patients with Lumbar Spinal Canal Stenosis.

Introduction: Frailty is an important factor in surgical outcomes. The current study aimed to evaluate the effect of preoperative frailty on postoperative outcomes in older patients with lumbar spinal canal stenosis (LSCS). Methods: We retrospectively examined 209 patients aged ≥65 years who underwent surgery for LSCS. Health-related quality-of-life (HRQOL) tools, including the Roland-Morris Disability Questionnaire (RDQ), Zurich Claudication Questionnaire (ZCQ), and Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ), were used in the assessment conducted before surgery and at 6 months and 1 year after surgery. Frailty was categorized based on the 11-item modified frailty index (mFI-11). Patients with mFI-11 of 0, <0.21, and >0.21 were classified under the robust (R), pre-frailty (P), and frailty (F) groups, respectively. Results: According to the mFI-11, 24, 138, and 47 patients were included in the R, P, and F groups, respectively. Regarding preoperative radiographic parameters, there was a remarkable increase in the sagittal vertical axis and a significant decrease in the development of lumbar lordosis with frailty progression. The preoperative scores of RDQ and ZCQ, and lumbar function, walking ability, social life, and psychological disorder domain scores of JOABPEQ differed significantly among these groups. The frequency of revision surgery was not higher in the F group than in the other groups. After adjustment for factors have shown different distributions among the three groups, the frequency of effective surgical cases did not show a clear trend among the three groups in all domains of the JOABPEQ. Conclusions: The preoperative HRQOL scores and the radiographic parameters of patients with LSCS worsened with frailty severity. However, frailty did not affect the rate of revision surgery and surgical efficacy in patients with LSCS. Although this study has limitations, our findings indicated that even LSCS patients with frailty can be considered for surgery if they have an indication for LSCS surgery.

Developmental cervical spinal canal size: population reference range.

Background: The developmental size of the cervical spinal canal varies considerably. Neural compression and injury are more likely with a developmentally small spinal canal. This study was designed to develop a population reference range for developmental cervical spinal canal size for the Hong Kong population. Methods: Prospective study of 522 ambulatory patients (256 males, 266 females, mean age 55±18 years; range, 20-89 years) who underwent computed tomography (CT) neck examinations. Using a manually operated segmentation program, spinal canal, and vertebral body cross-sectional area (CSA), anteroposterior (AP) sagittal diameter, and width were measured at each level from C3-C7. Patient height and weight were measured. Results: Considerable variation in spinal canal size existed with, for example, a 164-168% variation exists for males and females between the largest and smallest spinal canal CSA at C5. All spinal canal measurements increased slightly with height (r=0.25-0.36, P<0.001), while vertebral body AP sagittal diameter increased with age (r=0.48-0.51, P<0.001). All spinal canal measurements were larger (<0.0001) in males. Although spinal canal CSA was larger in males (at C5, males 276.0±41.5 mm2; females 252.6±38.4 mm2), relative to vertebral body CSA, spinal canal CSA was larger in females. Arbitrary population thresholds indicating the smallest 25% spinal canal CSA and AP sagittal diameter as well as other parameters were defined. Conclusions: There is a large variation in developmental cervical spinal canal size within the Hong Kong population. A reference range of developmental spinal canal size was developed which will enable an objective assessment of an individual's cervical spinal canal size relative to the wider population.

Pneumorrhachis as a complication of a severe pressure ulcer: An unique case report.

Pneumorrhachis is a medical condition that refers to the presence of air within the spinal canal. Many circumstances, including trauma, infection, or medical procedures, might lead to this syndrome.In some cases, pneumorrhachis may not cause any symptoms and can resolve on its own. However, it can also be associated with more severe underlying conditions, such as spinal fractures, spinal infections, or underlying lung pathologies that lead to air escaping into the spinal canal. In this case we report an incidental finding of pneumorrhachis in a patient who came to our attention for suspected sepsis.

A new etiology of nontraumatic C0-C1-C2-Complex instability - abnormality of musculus rectus capitis posterior minor: a case report.

PURPOSE: This study presents an abnormality of the musculus rectus capitis posterior minor (RCPmi) as a new etiological factor for nontraumatic sagittal plane instability in the C0-C1-C2-complex, with a focus on identifying the absence or atrophy of RCPmi on both sides. METHODS: A 36-year-old male patient presented with recurring neck pain (VAS 8/10) and tingling paresthesia in the entire left hand over a six-month period, without significant neurological deficits. Radiated arm pain was not reported. Imaging examinations revealed sagittal plane instability in the C0-C1-C2-complex, spinal canal stenosis (SCS), and myelopathy at the C1 level. Subsequently, a dorsal C0-1 reposition and fusion with laminectomy were performed. RESULTS: The congenital absence or atrophy of RCPmi, leading to the lack of cephalad-rearward traction on the C1-tuberculum-posterius, induced a developmental failure of the C1 posterior arch. Consequently, the oblate-shaped C1 posterior arch lost support from the underlying C2 posterior arch and the necessary cephalad-rearward traction throughout the patient's 36-year life. This gradual loss of support and traction caused the C1 posterior arch to shift gradually to the anterior side of the C2 posterior arch, resulting in a rotational subluxation centered on the C0/1 joints in the sagittal plane. Ultimately, this led to SCS and myelopathy. Traumatic factors were ruled out from birth to the present, and typical degenerative changes were not found in the upper cervical spine, neck muscles, and ligaments. CONCLUSION: In this case, we not only report the atrophy or absence of RCPmi as a new etiological factor for nontraumatic sagittal plane instability in the C0-C1-C2-complex but also discovered a new function of RCPmi. The cephalad-rearward traction exerted by RCPmi on the C1 posterior arch is essential for the development of a normal C1 anterior-posterior diameter.

Carpal tunnel syndrome, spinal canal stenosis, cardiomyopathy, renal insufficiency, enteropathy, and diffuse myopathy as an expression of systemic ATTR amyloidosis - diagnostics and therapy.

Systemic amyloidosis is an incurable multisystem disease, caused by fibrillar protein deposits with resulting dysfunction of affected organ systems. It mostly affects patients > 60 years. Diagnosis is often delayed because the symptoms are nonspecific and highly variable. We report on an elderly patient with multi-organ involvement with proven wild-type transthyretin amyloidosis. The initial manifestation involved bilateral carpal tunnel syndrome and lumbar spinal canal stenosis. The occurrence of ligament and tendon disorders, unexplained muscle pain and polyneuropathy in elderly patients should be considered as a possible first manifestation of systemic amyloidosis.

Long-term oral meclozine administration improves survival rate and spinal canal stenosis during postnatal growth in a mouse model of achondroplasia in both sexes.

Achondroplasia (ACH) is a skeletal dysplasia characterized by short-limbed short stature caused by the gain-of-function mutations in the fibroblast growth factor receptor 3 (FGFR3) gene. Activated FGFR3, which is a negative regulator of bone elongation, impairs the growth of long bones and the spinal arch by inhibiting chondrocyte proliferation and differentiation. Most patients with ACH have spinal canal stenosis in addition to short stature. Meclozine has been found to inhibit FGFR3 via drug repurposing. A 10-d treatment with meclozine promoted long-bone growth in a mouse model of ACH (Fgfr3ach mice). This study aimed to evaluate the effects of long-term meclozine administration on promoting bone growth and the spinal canal in Fgfr3ach mice. Meclozine (2 mg/kg/d) was orally administered to Fgfr3ach mice for 5 d per wk from the age of 7 d to 56 d. Meclozine (2 mg/kg/d) significantly reduced the rate of death or paralysis and improved the length of the body, cranium, and long bones in male and female Fgfr3ach mice. Micro-computed tomography analysis revealed that meclozine ameliorated kyphotic deformities and trabecular parameters, including BMD, bone volume/tissue volume, trabecular thickness, and trabecular number at distal femur of Fgfr3ach mice in both sexes. Histological analyses revealed that the hypertrophic zone in the growth plate was restored in Fgfr3ach mice following meclozine treatment, suggesting upregulation of endochondral ossification. Skeletal preparations demonstrated that meclozine restored the spinal canal diameter in Fgfr3ach mice in addition to improving the length of each bone. The 2 mg/kg/d dose of meclozine reduced the rate of spinal paralysis caused by spinal canal stenosis, maintained the growth plate structure, and recovered the bone quality and growth of axial and appendicular skeletons of Fgfr3ach mice in both sexes. Long-term meclozine administration has the potential to ameliorate spinal paralysis and bone growth in patients with ACH.

[Analysis of effectiveness of one-hole split endoscopy technique in treatment of lumbar spinal stenosis].

Objective: To investigate the effectiveness of one-hole split endoscope (OSE) technique in the treatment of single segment lumbar spinal stenosis (LSS). Methods: The clinical data of 32 single segment LSS patients treated with OSE technique for simple spinal canal decompression between January 2022 and December 2022, who met the selection criteria, were retrospectively analysed. There were 18 males and 14 females, the age ranged from 45 to 82 years, with an average of 65.1 years. The disease duration was 9-72 months, with an average of 34.9 months. The surgical segments included L 3, 4 in 3 cases, L 4, 5 in 19 cases, and L 5, S 1 in 10 cases. The incision length, operation time, intraoperative blood loss, intraoperative radiation exposure frequency, postoperative mobilization time, and the area of the patient's lesion segment dural sac before operation and at 1 month after operation were recorded. Low back pain and leg pain were assessed by visual analogue scale (VAS) score before operation and at 3 days, 3 months, and 12 months after operation; functional recovery was assessed by Oswestry disability index (ODI) before operation and at 3 months and 12 months after operation; the effectiveness was assessed by modified MacNab criteria at last follow-up. Results: All 32 patients successfully completed the operation, with an average incision length of 2.05 cm, an average operation time of 88.59 minutes, an average intraoperative blood loss of 46.72 mL, an average intraoperative radiation exposure frequency of 3.84 times, and an average postoperative mobilization time of 11.66 hours. All patients were followed up 12-16 months, with an average of 13.5 months. One patient experienced lower limb numbness, pain, and decreased muscle strength after operation, while the remaining patients did not experience complications such as dural tear or important nerve damage. The VAS scores of low back pain and leg pain and ODI in patients at various time points after operation were significantly better than preoperative ones, and each indicator further improved with time. The differences between time points were significant ( P<0.05). At 1 month after operation, the area of the patient's lesion segment dural sac was (123.13±19.66) mm 2, which significantly increased compared to preoperative (51.25±9.50) mm 2 ( t=-18.616, P<0.001). At last follow-up, the improved MacNab criteria were used to evaluate the effectiveness, with 18 cases achieving excellent results, 11 cases being good, and 3 cases being fair, with an excellent and good rate of 90.6%. Conclusion: The effectiveness of using OSE technique for simple spinal canal decompression treatment of single segment LSS is satisfactory, with the advantages of minimal surgical trauma and fast recovery.