Facet Osteoarthritis Research Articles

The location of the centre of the proximal quadriceps tendon in kinematically aligned total knee arthroplasty is not associated with poor outcome scores or symptomatic patellar instability.

A previous study on osteoarthritic knees found that the average position of the centre of the proximal quadriceps tendon (PQT) was 9 mm lateral from the native trochlear groove. In patients with lateral patellar facet osteoarthritis, which indicates patellofemoral instability, the average location was 21 mm. The researchers suggested that a position more lateral than 20 mm might lead to poor outcomes after kinematically aligned total knee arthroplasty (KA TKA)-the current study aimed to test this hypothesis. The study involved all patients (n = 302) who underwent KA TKA (n = 313) in 2019, had a post-operative long-leg scanogram and knee computed tomography scan, and completed a 2-year questionnaire. An evaluator measured the location of the PQT relative to the centre of the distal prosthetic trochlear groove. A Spearman's rank correlation coefficient analysis determined whether there was an association between the location of the PQT and the Forgotten Joint Score (FJS) and Oxford Knee Score (OKS) at 2 years. The mean location of the PQT was 11 ± 8 mm (range, -2 medial to 36 mm lateral), with 16% (N = 46) of the KA TKAs having a more lateral location than 20 mm. The location of the PQT was not associated with the FJS (r = -0.0349, p = 0.7281) and OKS (r = -0.0641, p = 0.9009)-no patient response indicated symptoms or operative treatment for patellofemoral instability. Even though 16% of patients with a KA TKA had a more lateral location than 20 mm, there is no reason to measure the centre of the PQT relative to the distal prosthetic groove. This is because the location did not show any association with the 2-year FJS and OKS nor had any patient experienced patellofemoral instability. IV.

The Relationship Between Craniocervical Morphology and the Presence and Level of Cervical Facet Joint Degeneration.

To investigate the relationship between craniocervical morphology and the presence and level of cervical facet joint degeneration (FJD). A total of 108 consecutive female patients aged 45-55 years who had undergone neck + brain CT angiography were included in this retrospective sectional study. Only patients of a certain age and of the same gender were included in order to eliminate the differences that create a disposition to the development of spinal degeneration. The presence of facet joint (FJ) arthritis (grade ≥2 degeneration in at least one affected facet joint) and the grade of the facet joint degeneration for each patient were recorded. A total of 20 lengths and 3 angles of craniocervical morphology were measured. The differences between the individuals with and without FJ arthritis were investigated with the independent-sample t test, and the relationship between the FJD grade and craniocervical morphology was investigated using the Spearman correlation test. Individuals with FJ arthritis were found to have longer Grabb-Oakes measurement, shorter FM AP length, lower ADI, lower EOP thickness, higher clivus length, higher crista gall-ATS distance, lower CCA angle, lower distance between the C1 vertebra lateral masses, and higher BAI than those without FJ arthritis (P ˂ 0.05). Besides, we found that the FJD grade increased as the Grabb-Oakes measurement increased, ADI distance decreased, FM AP length decreased, EOP thickness decreased, clivus length increased, basal angle increased, distance between the C1 vertebra lateral masses decreased, and BAI increased (P ˂ 0.05). Differences in craniocervical morphology are statistically associated with degenerative processes that result in degenerative changes in the facet joint. Therefore, some morphological changes in craniocervical anatomy cause changes in the momentum and distribution of the load on the facet joints, predisposing the patient to facet arthropathy and osteoarthritis.

Severe Lateral Facet Patella Osteoarthritis Is Not Associated With Increased Failure at Mean 10 Years After Lateral Unicompartmental Knee Arthroplasty

BackgroundThe purpose of this study was to determine if severe lateral patella facet osteoarthritis was related to lower survivorship and poor patient-reported outcomes following fixed-bearing lateral unicompartmental knee arthroplasty (UKA). MethodsThere were 61 patients who underwent a fixed-bearing, nonrobotically assisted, lateral UKA between May 7, 2003 and December 18, 2019 and met the inclusion criteria. The patello-femoral joint was examined intraoperatively for chondral damage prior to UKA implantation. Severe lateral facet patella osteoarthritis (LFPOA) was defined as Outerbridge grades 3 or 4 changes on the lateral facet. All patients completed subjective functional outcomes questionnaires and a clinical examination at a minimum of 4 years following UKA. ResultsSevere LFPOA was identified in 28 (46%) patients. At a mean follow-up of 10.9 years, there were no statistically significant differences in any Knee Osteoarthritis Outcomes Score (KOOS) subscale or Kujala scores between patients who had and did not have severe LFPOA. There was no statistically significant difference in the percentage of patients who achieved Patient Acceptable Symptom State for the KOOS subscale scores between groups. Mean survival in patients who did not have severe LFPOA was 16.6 years (95% confidence interval, 15.4 to 17.7) compared to 18.9 years (95% confidence interval, 17.6 to 20.2) in patients who had severe LFPOA (P = 0.62). ConclusionsSevere LFPOA did not result in lower survival or inferior functional outcomes compared to patients who did not have severe osteoarthritis at an average 10-year follow-up after fixed-bearing lateral UKA.

Baastrup’s disease prevalence across various age groups and its association with degenerative changes: insights from STIR sequence in MRI

PurposeBaastrup’s disease is characterized by abnormal contact between adjacent spinous processes. Our study is the first to systematically incorporate the STIR sequence, recognized for its heightened sensitivity to fluid and edema, into the MRI protocol for diagnosing Baastrup’s disease in symptomatic individuals. The objective is to determine its prevalence and association with lumbar spinal degenerative changes.Materials and methodsLumbar spinal MRI examinations of 375 patients performed between January 2021 and 2022 were retrospectively reviewed by two radiologists. Baastrup’s disease was diagnosed based on meeting any of the following criteria: lumbar interspinous bursitis, hyperintense signal changes in adjacent spinous processes, and ligaments on the STIR sequence. The study also investigated the presence of degenerative changes and interreader agreement among radiologists.ResultsBaastrup’s disease was found in 141 of 375 individuals (37.8%). It correlated significantly with degenerative lumbar changes such as bulging (P = 0.0012), herniation (P = 0.0033), disc degeneration (P = 0.0013), Modic changes (P = 0.034), facet osteoarthritis (P = 0.0041), spinal stenosis (P = 0.005), and anterolisthesis (P = 0.0049). No significant associations were observed with gender (P = 0.468) or retrolisthesis (P = 0.167). Its occurrence increased gradually, peaking at 87.5% in individuals aged 80 and above. Radiologists showed complete agreement with Baastrup’s diagnoses.ConclusionBaastrup’s disease is more commonly observed than being considered rare, displaying an incremental occurrence with increasing age in symptomatic individuals notably discernible on the STIR sequence. Using the STIR sequence seems to promote a consensus among radiologists, irrespective of their experience levels.

Minimally Invasive Treatment of Facet Osteoarthritis Pain in Spine: A Clinical Approach Evaluating Cryotherapy

Chronic pain management remains a challenging aspect of neurosurgical care, with facet arthrosis being a significant contributor to the global burden of low back pain. This study evaluates the effectiveness of cryotherapy as a minimally invasive treatment for patients with facet arthrosis. By focusing on reducing drug dependency and pain intensity, the research aims to contribute to the evolving field of pain management techniques, offering an alternative to traditional pain management strategies. Through a retrospective longitudinal analysis of patients with facet osteoarthritis treated via cryotherapy between 2013 and 2023, we evaluated the impact on medication usage and pain levels, utilizing the Visual Analog Scale for pre- and posttreatment comparisons. The study encompassed 118 subjects, revealing significant pain alleviation, with Visual Analog Scale scores plummeting from 9.0 initially to 2.0 after treatment. Additionally, 67 patients (56.78%) reported decreased medication consumption. These outcomes underscore cryotherapy's potential as a pivotal tool in chronic pain management. The findings illuminate cryotherapy's efficacy in diminishing pain and curtailing medication dependency among patients with facet arthrosis. This study reaffirms cryotherapy's role in pain management and propels the discourse on nontraditional therapeutic avenues, highlighting the urgent need for personalized and innovative treatment frameworks.

Gut-spine axis: a possible correlation between gut microbiota and spinal degenerative diseases.

As society ages, the number of patients with spinal degenerative diseases (SDD) is increasing, posing a major socioeconomic problem for patients and their families. SDD refers to a generic term for degenerative diseases of spinal structures, including osteoporosis (bone), facet osteoarthritis (joint), intervertebral disk degeneration (disk), lumbar spinal canal stenosis (yellow ligament), and spinal sarcopenia (muscle). We propose the term "gut-spine axis" for the first time, given the influence of gut microbiota (GM) on the metabolic, immune, and endocrine environment in hosts through various potential mechanisms. A close cross-talk is noted between the aforementioned spinal components and degenerative diseases. This review outlines the nature and role of GM, highlighting GM abnormalities associated with the degeneration of spinal components. It also summarizes the evidence linking GM to various SDD. The gut-spine axis perspective can provide novel insights into the pathogenesis and treatment of SDD.

Mechanical crosstalk between the intervertebral disc, facet joints, and vertebral endplate following acute disc injury in a rabbit model.

Vertebral endplate sclerosis and facet osteoarthritis have been documented in animals and humans. However, it is unclear how these adjacent pathologies engage in crosstalk with the intervertebral disc. This study sought to elucidate this crosstalk by assessing each compartment individually in response to acute disc injury. Eleven New Zealand White rabbits underwent annular disc puncture using a 16G or 21G needle. At 4 and 10 weeks, individual compartments of the motion segment were analyzed. Discs underwent T 1 relaxation mapping with MRI contrast agent gadodiamide as well T 2 mapping. Both discs and facets underwent mechanical testing via vertebra-disc-vertebra tension-compression creep testing and indentation testing, respectively. Endplate bone density was quantified via μCT. Discs and facets were sectioned and stained for histology scoring. Intervertebral discs became more degenerative with increasing needle diameter and time post-puncture. Bone density also increased in endplates adjacent to both 21G and 16G punctured discs leading to reduced gadodiamide transport at 10 weeks. The facet joints, however, did not follow this same trend. Facets adjacent to 16G punctured discs were less degenerative than facets adjacent to 21G punctured discs at 10 weeks. 16G facets were more degenerative at 4 weeks than at 10, suggesting the cartilage had recovered. The formation of severe disc osteophytes in 16G punctured discs between 4 and 10 weeks likely offloaded the facet cartilage, leading to the recovery observed. Overall, this study supports that degeneration spans the whole spinal motion segment following disc injury. Vertebral endplate thickening occurred in response to disc injury, which limited the diffusion of small molecules into the disc. This work also suggests that altered disc mechanics can induce facet degeneration, and that extreme bony remodeling adjacent to the disc may promote facet cartilage recovery through offloading of the articular cartilage.

Lateral Patella Facet Osteoarthritis is Not Contraindicated for Medial UKA: Mean 10-Year Outcomes and Survivorship

Lateral Patella Facet Osteoarthritis is Not Contraindicated for Medial UKA: Mean 10-Year Outcomes and Survivorship

Image quality and lesion detectability of deep learning-accelerated T2-weighted Dixon imaging of the cervical spine.

To validate the subjective image quality and lesion detectability of deep learning-accelerated Dixon (DL-Dixon) imaging of the cervical spine compared with routine Dixon imaging. A total of 50 patients underwent sagittal routine Dixon and DL-Dixon imaging of the cervical spine. Acquisition parameters were compared and non-uniformity (NU) values were calculated. Two radiologists independently assessed the two imaging methods for subjective image quality and lesion detectability. Interreader and intermethod agreements were estimated with weighted kappa values. Compared with the routine Dixon imaging, the DL-Dixon imaging reduced the acquisition time by 23.76%. The NU value is slightly higher in DL-Dixon imaging (p value: 0.015). DL-Dixon imaging showed superior visibility of all four anatomical structures (spinal cord, disc margin, dorsal root ganglion, and facet joint) for both readers (p value: < 0.001 ~ 0.002). The motion artifact scores were slightly higher in the DL-Dixon images than in routine Dixon images (p value = 0.785). Intermethod agreements were almost perfect for disc herniation, facet osteoarthritis, uncovertebral arthritis, central canal stenosis (κ range: 0.830 ~ 0.980, all p values < 0.001) and substantial to almost perfect for foraminal stenosis (κ = 0.955, 0.705 for each reader). There was an improvement in the interreader agreement of foraminal stenosis by DL-Dixon images, from moderate to substantial agreement. The DLR sequence can substantially decrease the acquisition time of the Dixon sequence with subjective image quality at least as good as the conventional sequence. And no significant differences in lesion detectability were observed between the two sequence types.

Síndrome Facetária Lombar

Low back pain originating from lumbar facet joints or zygapophyseal joints has been identified as a potential cause of low back pain. Facet osteoarthritis, a degenerative pathology, is the most common cause of facet pain, and its prevalence increases with age. Facet syndrome is a frequent diagnosis in rhythmic and acrobatic gymnastics athletes, surfing, bodyboarding, and yoga, due to its characteristic repetitive and / or maintained movements of hyperextension and rotation of the lumbar spine. The facet syndrome does not yet reach consensus from its diagnosis to the therapeutic strategies adopted, being still poorly understood, and probably underdiagnosed, which implies the need for further investigation.

Impact of Adjacent Facet Joint Osteoarthritis on Adjacent Segment Degeneration after Short-Segment Lateral Lumbar Interbody Fusion for Indirect Decompression: Minimum 5-Year Follow-Up.

Purpose Lumbar fusion combined with lateral lumbar interbody fusion (LLIF) and percutaneous pedicle screws (PPS) is a widely used, minimally invasive surgical treatment, but studies on incidence and risk factors for subsequent adjacent segment degeneration (ASD) are limited. This study was aimed at investigating midterm incidence and reoperation rate of ASD after indirect decompression (IDD) with LLIF and PPS and at clarifying the impact of preexisting adjacent facet osteoarthritis on development of ASD after IDD. Methods Forty-one patients who underwent short-segment (1- or 2-level) lumbar fusion with LLIF and PPS with a minimum 5-year follow-up were analyzed. Cephalad adjacent facet osteoarthritis was classified as 1 (normal) to 4 (severe) by an established classification system on preoperative CT. ASD was diagnosed with plain radiographs taken preoperatively and up to 5 years postoperatively, and preoperative degree of facet osteoarthritis was compared between the ASD+ group and ASD- group (control). We also divided patients into two groups according to severity of facet degeneration, mild (grades 1-2) group and severe (grades 3-4) group, and investigated ASD-free survival of the groups by the Kaplan-Meier method. Results The incidence of ASD at 5 years postoperatively was 34.1%, and the reoperation rate for ASD was 4.9%. The degree of preexisting facet joint osteoarthritis was significantly different between the ASD+ and ASD- groups (grade 1/2/3/4: 0/29/64/7% and 29/62/29/10%, P = 0.008). Kaplan-Meier analysis showed the severe group to have significantly lower ASD-free survival than the mild group (P = 0.017) at 5 years postoperatively. Conclusion Comparative analysis of the ASD+ versus ASD- group showed preexisting facet joint osteoarthritis to be a risk factor for ASD progression after IDD. Additional longitudinal studies with long-term follow-up are needed to understand the causal relationship between facet joint degeneration and progression of adjacent segment deterioration following IDD.

Level dependent alterations in human facet cartilage mechanics and bone morphometry with spine degeneration.

The zygapophyseal joints of the spine, also known as the facet joints, are paired diarthrodial joints posterior to the intervertebral disc and neural elements. The pathophysiology of facet osteoarthritis (OA), as well as crosstalk between the disc and facets, remains largely understudied compared to disc degeneration. The purpose of this study was to characterize alterations to human facet cartilage and subchondral bone across a spectrum of degeneration and to investigate correlations between disc and facet degeneration. Human lumbar facet articular surfaces from six independent donors were subject to creep indentation mechanical testing to quantify cartilage mechanical properties, followed by microcomputed tomography (µCT) analyses for subchondral bone morphometry. The degenerative state of each articular surface was assessed via macroscopic scoring and via Osteoarthritis Research Society International histopathology scoring. Our data suggest reduced facet cartilage compressive and tensile moduli and increased permeability with increasing degenerative grade, particularly at the lower levels of the spine. µCT analyses revealed spinal level-dependent alterations to the subchondral bone, with an increase in trabecular bone at the L4-L5 level, but a decrease at the upper levels of the lumbar spine with increasing degenerative grade. Cortical bone volume fraction was generally decreased with increasing degenerative grade across spinal levels. Correlation analysis revealed several associations between quantitative measures of disc degeneration and facet OA. This study showed that alterations in the mechanical properties of facet cartilage and in the structural properties of facet subchondral bone correlated with aspects of disc degeneration and were highly dependent on spinal level.

Association of presurgical circulating MicroRNAs with 1-year postsurgical pain reduction in spine facet osteoarthritis patients with lumbar spinal stenosis

PurposeUp to 30% of spine facet osteoarthritis patients with lumbar spinal stenosis (SF-OA ​+ ​LSS) have little to no improvement in their pain after surgery. Lack of meaningful improvement in pain following surgery provides a unique opportunity to identify specific predictive biomarker signatures that might be associated with the outcomes of surgical treatment. The objective of the present study was to determine whether a microRNA (miRNA) biomarker signature could be identified in presurgical blood plasma that corresponded with levels of SF-OA ​+ ​LSS patient post-surgical pain intensity one year later. MethodsRNA was extracted from baseline plasma of SF-OA ​+ ​LSS patients and prepared for miRNA sequencing. Statistical approaches were performed to identify differentially expressed miRNAs associated with reduced 1-year postsurgical pain (n ​= ​56). Using an integrated computational approach, we further created predicted gene and pathway networks for each identified miRNA. ResultsWe identified a panel of 4 circulating candidate miRNAs (hsa-miR-155-5p, hsa-let-7e-5p, hsa-miR-125a-5p, hsa-miR-99b-5p) with higher levels at presurgical baseline that were associated with greater changes in % NPRS20Δ, reflecting reduced pain intensity levels at one year. Genes encoding hsa-let-7e-5p, hsa-miR-125a-5p, and hsa-miR-99b-5p are part of an evolutionarily conserved miRNA cluster. Using integrated computational analyses, we showed that mammalian target of rapamycin, transforming growth factor-β1 receptor, Wnt signaling, epithelial–mesenchymal transition regulators, and cholecystokinin signaling were enriched pathways of predicted gene targets. ConclusionsTaken together, our findings suggest that 4 presurgical baseline circulating miRNAs correlate with 1-year postsurgical SF-OA ​+ ​LSS patient pain intensity and represent possible candidate biomarker signature of surgical pain response.

Upregulation of P2Y12 inhibits chondrocyte apoptosis in lumbar osteoarthritis through the PI3K/AKT signaling pathway.

Lumbar facet osteoarthritis (FJOA) is a major cause of severe lower back pain and disability worldwide. However, the mechanism underlying cartilage degeneration in FJOA remains unclear. The purpose of this study was to investigate the regulation and mechanism of P2Y12 on chondrocyte apoptosis in FJOA. The experimental rats were randomly divided into non-operation (n = 20) and operation groups (n = 20). In the operation group, Sodium iodoacetate (MIA, Sigma, 200mg/mL) was injected into the right L4/5 facet process using a blunt nanoneedle 26 (WPI, Sarasota, FL, USA) under the control of an injection pump. The final injection volume was 5µL and the injection rate was 2µL/min. The facet joint was removed four weeks after surgery. After the operation, samples were stored at -80°C until further use, whereby the right facet joints in each group were tested. Hematoxylin and eosin (HE) and iron-red solid green staining were used to observe the degeneration of articular chondrocytes in rats. Immunohistochemistry and western blotting were used to observe the expressions of P2Y12, Matrix metalloproteinase 13 (MMP13), Collagen II (COL2), and other cartilage degeneration and apoptosis-related genes. Co-localization of P2Y12-cleaved caspase-3 in the apoptosis model was detected by dual-standard immunofluorescence staining. Apoptosis was also detected by flow cytometry and TUNEL assay.P2Y12 is highly expressed in OA cartilage tissue, and inhibits IL-1β -induced chondrocyte apoptosis through PI3K/AKT signaling pathway, thus playing a certain protective role on cartilage.

Research progress of spontaneous facet fusion after lumbar spine surgery

To summarize the research progress on spontaneous facet fusion (SFF) after lumbar spine surgery, and provide reference for further research on SFF. The definition, development, clinical significance, and related influence factors of SFF were throughout reviewed by referring to relevant domestic and foreign literature in recent years. SFF is a phenomenon of joint space disappearance and fusion of upper and lower articular processes, which starts in a ring shape from the outermost edges to the central regions. Currently reported SFF occurred after posterior lumbar pedicle screw fixation. SFF may increase the stability of surgical segments and relieve clinical symptoms of patients. SFF is closely related to the method of lumbar internal fixation, facet osteoarthritis, interbody fusion, age, body mass index, type B fracture (according to AO classification), and the operative segment. Most reported SFF occur after posterior lumbar pedicle screw fixation, which can increase lumbar stability, but the mechanism and influencing factors remain to be further clarified.

Factors Associated with Treatment Success After Interlaminar Epidural Steroid Injection for Cervical Radicular Pain.

To investigate the demographic, clinical and radiological findings associated with treatment success after interlaminar epidural steroid injection (ILESI) in radicular pain induced by cervical disc herniation. In this retrospective study, the data of patients who received cervical ILESI between January 2017 and June 2021 were screened. Of 223 patients, 92 with unilateral radicular neck pain due to cervical disc herniation were included. Demographic data, symptom duration, and numerical rating scale scores at baseline, at three weeks, three months, and six months after treatment were collected from the medical records of the patients. Disc herniation level, cervical axis, disc height, presence and degree of spinal canal and neural foraminal stenosis, vertebral endplate signal change, and definitive presence of uncovertebral and facet osteoarthritis were evaluated using cervical spine magnetic resonance imaging. Treatment success was determined as ?50% reduction in pain scores at six months compared to baseline. Data of 92 patients (27 men, 65 women) were included. The mean age was 50.82 ± 10.22 years, and the median symptom duration was 12 (4.25 to 20) months. At six months after ILESI, treatment was successful in 58 (58.7%) patients and unsuccessful in 34 (41.3%) patients. Multivariable logistic regression analysis was performed to identify the factors associated with treatment success at six months post-injection. In the final model, neural foraminal stenosis (non-severe vs. severe) and spinal canal stenosis (non-severe vs. severe) were significantly associated with the treatment success (OR=3.02, 95% CI=1.40?10.95, p=0.009; OR=5.31, 95% CI=1.77?15.85, p=0.003). Treatment success of cervical ILESI at six months is favorable. However, the presence of severe neural foraminal and spinal canal stenosis is associated with a reduced likelihood of treatment success.

Facet Joint Violation by Thoracolumbar Percutaneous Pedicle Screw and Its Effect on Progression of Facet Joint Osteoarthritis.

Study DesignA retrospective study.PurposeThis study aimed to investigate the rate and associated factors of facet violation (FV) in percutaneous pedicle screws (PPS) from the thoracic to the lumbar spine and the effect of FV on facet osteoarthritis (OA) progression.Overview of LiteratureSome reports claim PPS has a higher FV rate than conventional open surgery. However, previous reports of FV in PPS were limited to the lumbar spine; only a few reports included the thoracic spine.MethodsThe present study includes 1,028 PPS inserted from T4 to S1 in 218 patients. The rate of FV and facet OA progression after FV were assessed using computed tomography (CT) scans conducted postoperatively at 1 week and 6 months or more. To identify factors associated with FV or facet OA progression after FV, a multivariate logistic regression analysis was conducted. To investigate whether FV caused facet OA progression, we compared OA progression between patients with FV and matched controls.ResultsFV was observed in 68 (6.6%) of the 1,028 facets, and the thoracic spine was identified as an independent factor associated with FV. OA progression was detected in 48.2% of the cases with FV via CT scans conducted postoperatively at a mean duration of 22.6 months. The time between CT scans was identified as an independent factor for facet OA progression after FV. The rate of OA progression in patients with FV was significantly greater than that of the controls.ConclusionsFV was observed in 6.6% of the patients, and the thoracic spine was identified as an independent factor associated with FV. OA progression of a violated facet occurs over time. FV is considered a complication leading to facet OA progression.

Standardized Classification of Lumbar Spine Degeneration on Magnetic Resonance Imaging Reduces Intra- and Inter-subspecialty Variability

Background and PurposeTo determine the efficacy of standardized definitions of degenerative change in reducing variability in interpretation of lumbar spine magnetic resonance imaging within and between groups of subspecialty-trained neuroradiologists (NR) and musculoskeletal radiologists (MSK). Materials and MethodsSix radiologists, three from both NR and MSK groups were trained on a standardized classification system of degenerative change. After an 11-month washout period, they independently re-interpreted fifty exams at the L4-L5 and L5-S1 levels. Responses were converted to a six-point ordinal scale for the assessment of neural foraminal stenosis and spinal canal stenosis (SCS), three-point scale for lateral recess stenosis, and four-point scale for facet osteoarthritis (FO). Intra-subspecialty and inter-subspecialty analysis was performed using the weighted Cohen's kappa with a binary matrix of all reader pairs. ResultsInter-subspecialty agreement improved from k=0.527 (moderate) to k=0.602 (substantial) for neural foraminal stenosis, from k=0.540 (moderate) to k=0.652 (substantial) for SCS, from k=0.0818 (slight) to k=0.337 (fair) for lateral recess stenosis, and from k=0.176 (slight) to k=0.495 (moderate) for FO. The NR group demonstrated improved intra-subspecialty agreement for the assessment of SCS, from k=0.368 (fair) to k=0.638 (substantial). The MSK group demonstrated improved intra-subspecialty agreement for the assessment of FO, from k=0.134 (slight) to k=0.413 (moderate). Intra-subspecialty agreement was similar for other parameters before and after training. ConclusionsAs result of the standardized definitions training, the NR and MSK groups each improved in one of the four parameters, while inter-subspecialty variability improved in all four parameters. These definitions may be useful in clinical practice across radiology subspecialties.

97. The utility of the AP view of cervical spine radiography in nontraumatic cervical spinal disorders

<h3>BACKGROUND CONTEXT</h3> While ordering the two-view cervical spine X-rays is a routine in evaluating patients with nontraumatic cervical spinal disorders, the anteroposterior (AP) view seems to provide relatively less information than the lateral view. Considering the radiation and cost of the examination, and given that most surgical patients would already have CT and/or MRI available, it is reasonable to examine the utility of the AP view in cervical spine radiography in nontraumatic conditions. <h3>PURPOSE</h3> This study aims to (a) examine how often the radiological reports of the cervical spine describe findings from an AP view and (b) survey senior spine surgeons nationwide regarding their utilization of the AP view in actual practice. <h3>STUDY DESIGN/SETTING</h3> Review of radiological reports using the technique of text-mining, followed by a survey of surgeons. <h3>PATIENT SAMPLE</h3> A total of 210 patients diagnosed with nontraumatic cervical spinal disorders at our hospital, and 24 senior spine surgeons nationwide. <h3>OUTCOME MEASURES</h3> Percentages of the radiological aspects of the cervical spine that are described in the radiological reports by view (AP vs lateral vs both views), percentages of the surgeons' responses. <h3>METHODS</h3> This study included two parts: a review of radiological reports and a survey of surgeons. In Part 1, radiological reports of the two-view cervical spine radiographs for patients diagnosed with nontraumatic cervical spinal disorders at a tertiary spine center were collected, excluding those with tumor or previous cervical spinal surgery. After the hospital's medical informatics service used programming algorithms to locate the first such radiography of each patient, the radiological reports were reviewed in two steps. Step 1 used the technique of text-mining to obtain 50 most frequently used words in the radiological reports so as to summarize the main radiological aspects of a cervical spine (eg, alignment, disc space, uncovertebral joint, etc.) Then, step 2 identified the source of each radiological aspect's description in the radiological report: Was it from the AP view, the lateral view, or both? For example, a sentence in the radiological report read, "Frontal view demonstrates no significant uncovertebral hypertrophy," and this indicates that this radiological aspect -the uncovertebral joint- was evaluated using the AP view. As another example, a report noted "disc space narrowing at C5-6 with prominent osteophyte." As disc space narrowing is inherently a lateral-view sign, this indicates that both the disc space and the osteophyte here in this report were described using the lateral view. In this way, each radiological aspect of the cervical spine was examined, recorded, and tallied in all of the radiological reports. Then in Part 2, a two-question survey asking surgeons whether they think the AP view is practically useful and why was distributed among a group of 37 senior spine surgeons nationwide, who were from a published survey study on a different topic. <h3>RESULTS</h3> A total of 210 radiological reports from 2006 and 2020 were eligible for inclusion. Together, they described 18 radiological aspects of the cervical spine. Of these 18 radiological aspects, 28% (5/18, eg, uncovertebral joint, transverse process) were described exclusively on the AP view, 50% (9/18, eg, lordosis, disc space) were exclusively on the lateral view, and 22% (4/18, eg, fracture, degenerative changes in general) could be from both views. These 18 radiological aspects varied in their frequency of presence in the radiological reports, ranging from disc degeneration (82%, 172/210) to cervical scoliosis (0.5%, 1/210). The AP view was used to describe uncovertebral joint (24%, 51/210), transverse process (3%, 6/210), lung apices (1%, 2/210), and some other signs. Three radiological aspects could be from both the AP and lateral views: alignment in general (81%, 171/210), fracture (53%, 112/210) and degenerative changes in general (26%, 54/210). The survey of surgeons obtained a response rate of 65% (24/37). Among the respondents, 63% (15/24) thought that the AP view is useful, and the reasons included showing deformity or alignment (47%, 7/15), showing facet osteoarthritis (27%, 4/15), showing clavicle or rib for spinal level localization (20%, 3/15) and showing the uncovertebral joints (20%, 3/15), among others. <h3>CONCLUSIONS</h3> For nontraumatic degenerative cervical spinal disorders, the AP view of the cervical spine radiography provides relatively less information than the lateral view. However, the radiological reports and surgeons' feedback suggest that the AP view is sometimes useful in actual practice. As such, the value of the AP view should be patient-specific and dependent upon whether the AP view is essential for the care of the specific patient. A granular practice guideline regarding when to and when not to order the AP view is needed, and warrants future research. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

SIGNIFICANCE OF SEDIMENTATION SIGN OF MAGNETIC RESONANCE IMAGING (MRI) IN LUMBAR CANAL STENOSIS

Lumbar spinal stenosis (LSS) is common sequelae of degenerative disorders of spine. Spinal canal stenosis is a narrowing in the spinal canal or neural foramina, causing compression on the spinal cord, cauda equina, or individual nerve roots, and it may be congenital or acquired. The acquired causes for Spinal canal stenosis are frequently occurring and can result from: facet osteoarthritis, ligamentum flavum hypertrophy, degenerative bulging disc, or osteophyte formation. The nerve root sedimentation (NRS) sign is a new radiological sign first reported by Barzet al.In the normal person during supine position, the nerve roots would sink posteriorly in the dural sac due to gravity. In those patients with LSS, the nerve root would not be able to sink but disperse ventrally. The NRS sign has been shown to discriminate well between patients with and without LSS and reported to be 94% sensitive and 100% specific. However, the sign is not widely used probably due to its limited reliability study. A positive sedimentation sign was defined as the absence of nerve root sedimentation in at least 1 axial MRI scan, at a level above or below, disregarding the location of the scan within the level and its proximity to the maximal stenosis.The only exception from this is the two nerve roots leaving the dural sac one segmental level below the stenosis. If there are nerve roots in the ventral part of the dural sac except for the ones exiting the dural sac, the sedimentation sign is positive.