Statin use and MRI subchondral bone marrow lesion worsening in generalized osteoarthritis: longitudinal analysis from Osteoarthritis Initiative data.

OBJECTIVES: To determine the association between statin therapy and knee MRI-detected subchondral bone marrow lesion (BML) longitudinal worsening in patients with Heberden's nodes (HNs) as the hallmark of generalized osteoarthritis (OA) phenotype. METHODS: All participants gave informed consent, and IRB approved HIPAA-compliant protocol. We assessed the worsening in BML volume and number of affected subregions in the Osteoarthritis Initiative (OAI) participants with HNs at baseline clinical examination (HN+), using the semi-quantitative MRI Osteoarthritis Knee Scores at baseline and 24 months. Participants were classified according to baseline BML involvement as "no/minimal" (≤ 2/14 knee subregions affected and maximum BML score ≤ 1) or "moderate/severe." Statin users and non-users were selected using 1:1 propensity-score (PS) matching for OA and cardiovascular disease (CVD)-related potential confounding variables. We assessed the association between statin use and increasing BML score and affected subregions using adjusted mixed-effect regression models. RESULTS: The PS-matched HN+ participants (63% female, aged 63.5 ± 8.5-year-old) with no/minimal and moderate/severe BML cohorts consisted of 332 (166:166, statin users: non-users) and 380 (190:190) knees, respectively. In the HN+ participants with no/minimal BML, statin use was associated with lower odds of both BML score worsening (odds ratio, 95% confidence interval: 0.62, 0.39-0.98) and increased number of affected subregions (0.54, 0.33-0.88). There was no such association in HN- participants or those HN+ participants with baseline moderate/severe BML. CONCLUSION: In patients with CVD indications for statin therapy and generalized OA phenotype (HN+), statin use may be protective against the OA-related subchondral bone damage only in the subgroup of participants with no/minimal baseline BML. KEY POINTS: • Statin use may reduce the risk of subchondral bone damage in specific osteoarthritis patients with a generalized phenotype, minimal subchondral bone damage, and cardiovascular statin indications.

Patient Experience Scores for Radiologists: Comparison With Nonradiologist Physicians and Changes After Public Posting in an Institutional Online Provider Directory.

BACKGROUND. Patients are increasingly using online information regarding patient experiences to guide care decisions. OBJECTIVE. The purpose of our study was to compare patient experience scores between radiologists and nonradiologist physicians and to assess changes in scores after their public posting in an online physician directory. METHODS. This retrospective study included data collected from May 1, 2017, to November 30, 2018, at a single large academic medical center. After all institutional outpatient visits, patients were e-mailed the Press Ganey Medical Practice Survey, which included 10 questions (answered using a Likert scale and converted to 100-point range) relating to the patient's experience with the specific provider for the encounter. Surveys were distributed to patients after radiology encounters if involving an image-guided invasive procedure. Mean scores for each question and the mean weighted overall score were displayed on each physician's publicly available profile on the hospital's online physician directory and were updated monthly. Scores were compared between radiologists and nonradiologist physicians; temporal changes were assessed. RESULTS. The response rate was 18.0% (96,057/533,983). After exclusions (23,989 surveys completed without provider ratings; 183 surveys evaluating physician assistants), 71,885 physician surveys were evaluated: 2703 surveys for 65 radiologists, 49,403 surveys for 916 physicians in 17 nonsurgical specialties, and 19,779 surveys for 262 physicians in 13 surgical specialties. Over the study period, the mean overall score was 95.6 for radiologists and 95.9 for nonradiologists (94.6 for surgical specialties, 96.4 for nonsurgical specialties). For the 10 individual questions, scores ranged for radiologists from 94.6 (time spent with patient) to 96.8 (friendliness/courtesy) and for nonradiologists from 94.6 (time spent with patient) to 97.0 (friendliness/courtesy). The mean overall score increased from the first month to the final month for radiologists from 94.2 to 97.1 and for nonradiologists from 95.7 to 96.3. For radiologists, the largest improvement was for instructions regarding postprocedure follow-up care (increased from 91.4 to 97.4). CONCLUSION. Radiologists received high scores on patient experience surveys when evaluated on encounters involving invasive procedures, achieving scores similar to those for other physicians. Scores improved over time, possibly related to online posting of survey results. CLINICAL IMPACT. The findings support the utility of implementing patient experience surveys in radiology.

Kinematic Tibiofibular Syndesmotic Measurements as Indicators of Tibiotalar Osteoarthritis: Exploratory Analysis Using 4-Dimensional Computed Tomography.

OBJECTIVE: The aim of this study was to evaluate the association between 4-dimensional computed tomography (4DCT)-derived measurements of tibiofibular syndesmosis during active dorsiflexion-plantarflexion motion and the presence of tibiotalar osteoarthritis (OA). METHODS: Sixteen ankle joints underwent 4DCT imaging during active dorsiflexion-plantarflexion. Syndesmotic anterior distance (SAD) and syndesmotic translation (ST) were obtained by a foot-and-ankle surgeon. We used Kellgren-Lawrence (KL) grading to determine tibiotalar OA. RESULTS: Of 16 scanned ankles, 12 ankles had KL ≥2 at the tibiotalar joint. In these ankles, SAD (-0.4, P = 0.02) and ST (-0.9, P = 0.006) measurements significantly changed during the dorsiflexion-plantarflexion motion. Changes in SAD measurements were significantly correlated with the KL grades (correlation coefficient: -0.688, P = 0.003); however, the changes in ST measurements were not significantly correlated with the KL grade. CONCLUSIONS: Our exploratory cross-sectional analysis shows that SAD measurement changes during motion using 4DCT are correlated with the tibiotalar OA grading. This measurement may be used but requires confirmation in larger studies including patients with actual syndesmotic injuries.

Evidence-based use of clinical examination, ultrasonography, and MRI for diagnosing ulnar collateral ligament tears of the metacarpophalangeal joint of the thumb: systematic review and meta-analysis.

OBJECTIVES: To determine the performances of clinical examination, ultrasonography, and MRI for diagnosing non-displaced and displaced ulnar collateral ligament (UCL) tears. METHODS: Based on a literature search of Medline, ISI Web of Science, Embase, and Scopus between January 1990 and December 2019, all published original articles which met the inclusion criteria were included. We determined the pooled sensitivities, specificities, and accuracies of clinical examination, ultrasonography, and MRI using a meta-analysis based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses-Diagnostic Test Accuracy (PRISMA-DTA) guidelines. RESULTS: A total of 17 studies with 519 subjects reporting diagnostic performances of clinical examination (8), ultrasonography (12), and MRI (5) met the inclusion criteria. For ruling out UCL tears, the pooled sensitivities were similarly high for clinical examination (97% (95% confidence interval [CI], 93-99%)), ultrasonography (96% (95% CI, 94-98%)), and MRI (99% (95% CI, 92-100%)) (p = 0.3). For ruling in UCL tears, the pooled specificities were higher for MRI (100% (95% CI, 87-100%)) when compared to ultrasonography (91% (95% CI, 86-95%)) (p = 0.1) and clinical examination (85% (95% CI, 78-91%)) (p = 0.04). For the diagnosis of displaced UCL tears, MRI had a higher specificity (92% (95% CI, 73-99%)) than ultrasonography (72% (95% CI, 63-80%)) (p = 0.2). CONCLUSIONS: Clinical examination, ultrasonography, and MRI have similarly high sensitivities for ruling out UCL tears in patients presenting with a thumb injury. MRI and ultrasonography have high specificities to confirm the presence of suspected UCL tears. MRI performs best for differentiating non-displaced from displaced UCL tears. KEY POINTS: • Clinical examination followed by ultrasonography is the most appropriate test for ruling out ulnar collateral ligament (UCL) tears of the thumb. • MRI and ultrasonography both have high specificities to confirm the presence of a suspected UCL tear. • MRI outperforms ultrasonography for differentiating non-displaced from displaced UCL tears.

Kneeling as a risk factor of patellofemoral joint cartilage damage worsening: an exploratory analysis on the Osteoarthritis Initiative.

OBJECTIVES: To determine whether kneeling activity is associated with the MRI measures of patellofemoral (PF) joint cartilage damage worsening in subjects with/without patella alta (PA). METHODS: Baseline and 24-month 3-T MR images and semi-quantitative MRI Osteoarthritis Knee Score (MOAKS) of PF joint of 600 subjects from the FNIH study, a nested study within the Osteoarthritis Initiative (OAI), were extracted. At baseline visit, subjects were asked how many days per week they participated in kneeling activities lasted ≥ 30 min. Insall-Salvati ratio (ISR) (patellar tendon/patellar height) was measured on baseline MRIs by a musculoskeletal radiologist; ISR ≥ 1.3 was considered PA. Regression analysis adjusted for confounding variables was used to assess the impact of kneeling on worsening of MOAKS cartilage over 24 months. The potential moderating effect of PA was evaluated using adjusted regression analysis. RESULTS: Six hundred subjects (58.8% female, years, BMI = 30.7 ± 4.8 kg/m2) were included; 13.7%, 6.2%, and 5.5% of participants reported 1 day, 2-5 days, and ≥ 6 days of kneeling activities per week. A higher frequency of kneeling activity was associated with the increased risk of MOAKS cartilage score worsening (adjusted OR (95% CI): 2.33 (1.08-5.06)). Stratification analysis showed that only ≥ 6 days/week of kneeling activities was associated with the worsening of MOAKS cartilage scores (2.74 (1.03-7.27)). When we included the presence of PA in regression models, the OR (95% CI) for the association between kneeling and PF cartilage damage will decrease to 1.26 (0.78-2.04), suggesting the potential role of PA as the moderator variable. CONCLUSION: Extensive kneeling activity (≥ 6 days/week) may be associated with the MRI-based worsening of PF cartilage damage, specifically in subjects with an underlying patella alta. KEY POINTS: • Frequent daily kneeling activity is associated with a higher risk of patellofemoral cartilage damage resulting in patellofemoral osteoarthritis. • The cartilage damage associated with extensive kneeling activity may be worse in subjects with an underlying patella alta (i.e., high-riding patella).

Association between Patellofemoral and medial Tibiofemoral compartment osteoarthritis progression: exploring the effect of body weight using longitudinal data from osteoarthritis initiative (OAI).

OBJECTIVES: To investigate the associations of medial and lateral patellofemoral osteoarthritis (PF-OA) at baseline with symptomatic and radiographic OA outcomes in the medial tibiofemoral compartment (MTFC) over 4 years, according to baseline overweight status. METHODS: Data and MRI images of 600 subjects in the FNIH-OA biomarkers consortium were used. Symptomatic worsening and radiographic progression of MTFC-OA were defined using Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain scores and MTFC joint space narrowing (JSN) from baseline to 4-year follow-up. Baseline MRIs were read to establish PF-OA diagnosis. The association between baseline regional PF-OA pattern and odds for MTFC-OA progression was evaluated using regression models (adjusted for relevant confounding covariates including body mass index (BMI), age, sex, PF alignment measurements, KL grade, and knee alignment). To evaluate the effect modifying role for overweight status, stratification analysis was performed (BMI ≥ 25 vs. < 25 kg/m2). RESULTS: At baseline, 340 (56.7%), 255 (42.5%), and 199 (33.2%) subjects had OA in the medial, lateral, and both PF compartments. Baseline medial PF-OA was associated with WOMAC pain score and MTFC JSN progression at 4 years (Adjusted OR:1.56[95%CI:1.09-2.23] and 1.59[1.11-2.28], respectively) but not lateral PF-OA. In stratification analysis, overweight status was found to be an effect modifier for medial PF-OA and WOMAC pain (OR in overweight vs. non-overweight subjects:1.65[1.13-2.42] vs. 0.50[0.12-1.82]) as well as MTFC-JSN progression (1.63[1.12-2.4] vs. 0.75[0.19-2.81]). CONCLUSIONS: In addition to the known confounding effect of BMI for PF-OA and MTFC-OA, the overweight status may also play an effect modifier role in the association between baseline medial PF-OA and MTFC-OA progression, which is amenable to secondary prevention.

Use of Advanced Imaging for Radiographically Occult Hip Fracture in Elderly Patients: A Systematic Review and Meta-Analysis.

Background The overall rate of hip fractures not identified on radiographs but that require surgery (ie, surgical hip fractures) remains unclear in elderly patients who are suspected to have such fractures based on clinical findings. Moreover, the importance of advanced imaging in these patients has not been comprehensively assessed. Purpose To estimate the frequency of radiographically occult hip fracture in elderly patients, to define the higher-risk subpopulation, and to determine the diagnostic performance of CT and bone scanning in the detection of occult fractures by using MRI as the reference standard. Materials and Methods A literature search was performed to identify English-language observational studies published from inception to September 27, 2018. Studies were included if patients were clinically suspected to have hip fracture but there was no radiographic evidence of surgical hip fracture (including absence of any definite fracture or only presence of isolated greater trochanter [GT] fracture). The rate of surgical hip fracture was reported in each study in which MRI was used as the reference standard. The pooled rate of occult fracture, diagnostic performance of CT and bone scanning, and strength of evidence (SOE) were assessed. Results Thirty-five studies were identified (2992 patients; mean age, 76.8 years ± 6.0 [standard deviation]; 66% female). The frequency of radiographically occult surgical hip fracture was 39% (1110 of 2835 patients; 95% confidence interval [CI]: 35%, 43%) in studies of patients with no definite radiographic fracture and 92% (134 of 157 patients; 95% CI: 83%, 98%) in studies of patients with radiographic evidence of isolated GT fracture (moderate SOE). The frequency of occult fracture was higher in patients aged at least 80 years (44%, 529 of 1184), those with an equivocal radiographic report (58%, 71 of 126), and those with a history of trauma (41%, 977 of 2370) (moderate SOE). CT and bone scanning yielded comparable diagnostic performance in the detection of radiographically occult hip fracture (P = .67), with a sensitivity of 79% and 87%, respectively (low SOE). Conclusion Elderly patients with acute hip pain and negative or equivocal findings at initial radiography have a high frequency of occult hip fractures. Therefore, the performance of advanced imaging (preferably MRI) may be clinically appropriate in all such patients. © RSNA, 2020 Online supplemental material is available for this article.

Patellofemoral morphology measurements and their associations with tibiofemoral osteoarthritis-related structural damage: exploratory analysis on the osteoarthritis initiative.

OBJECTIVES: Given the coexistence and possible interactions between patellofemoral and tibiofemoral compartments, roles of patellofemoral morphology measurements in tibiofemoral osteoarthritis (OA) have not been investigated extensively. We aimed to determine whether patellofemoral morphology is associated with the presence and longitudinal worsening of tibiofemoral OA in participants of the Osteoarthritis Initiative (OAI). METHODS: Baseline knee MRIs of 600 participants were read by two independent blinded observers in consensus to determine patellofemoral morphology measurements including tibial tuberosity to trochlear groove (TT-TG) distance, trochlear groove depth (TGD), lateral patellar tilt (LPT), and Insall-Salvati ratio (ISR). Radiographic and MRI OA knee scoring (MOAKS) measurements were extracted from baseline and 2-year follow-up readings. Associations between baseline patellofemoral morphology metrics with radiographic medial tibiofemoral compartment (MTFC) joint space loss (> 0.7 mm, between baseline and 2nd-4th-year readings), and MRI-derived cartilage damage, bone marrow lesions (BMLs), and osteophytes (baseline to 2 years), were investigated using regression models adjusted for age, sex, body mass index, and knee alignment. P values were corrected using the Benjamini-Hochberg procedure. RESULTS: Patellofemoral morphology measurements were not associated with longitudinal joint space loss in the MTFC or MOAKS determinants. Only TT-TG distance was associated with the baseline number of subregions with cartilage defects (OR (95% CI), 1.09 (1.04-1.14), corrected p value ≤ 0.01), BMLs (OR (95% CI), 1.1 (1.04-1.17), corrected p value = 0.01), and osteophytes (OR (95% CI), 1.09 (1.05-1.14), corrected p value ≤ 0.01) in the lateral tibiofemoral compartment (LTFC), and worsening of LTFC cartilage defects over 2 years (OR (95% CI), 1.09 (1.03-1.16), corrected p value = 0.02). CONCLUSIONS: Higher TT-TG distance was associated with concurrent MRI-derived OA-related structural damages and 2-year follow-up worsening only in LTFC. No associations were detected between patellofemoral morphology measurements and MTFC OA progression. KEY POINTS: • Of all patellofemoral morphology measurements, the only lateralization of the tibial tubercle may be considered as a risk factor for lateral (not medial) tibiofemoral osteoarthritis worsening. • Patellofemoral morphology measurements of patella alta, trochlear dysplasia, patellar tilt, and lateralization of the tibial tubercle are not associated with radiographic and MRI-based medial tibiofemoral osteoarthritis worsening over 2 years. • Using longitudinal MRI data, each millimeter increase of TT-TG distance is associated with a 9% (95% confidence interval, 3-16%) increase in odds of longitudinal cartilage defects in the lateral tibiofemoral (but not medial) compartment over 2 years.

Optimal Choice of Ultrasound-Based Measurements for the Diagnosis of Ulnar Neuropathy at the Elbow: A Meta-Analysis of 1961 Examinations.

OBJECTIVE. The purpose of this study was to determine the optimal ultrasound (US) measurement technique and cutoff value for the diagnosis of ulnar neuropathy at the elbow. MATERIALS AND METHODS. A systematic literature search was conducted of the PubMed, Embase, Scopus, and Web of Science databases for studies evaluating the diagnostic accuracy of US of patients with ulnar neuropathy at the elbow before April 2019. Random-effects modeling was performed to compare the sensitivity, specificity, and diagnostic odds ratio (DOR) of different US measurements, including diameter and cross-sectional area (CSA) of the nerve at the medial epicondyle or proximal and distal levels, maximal diameter, maximal CSA, and nerve ratios. Sensitivity and metaregression analyses were performed to assess the impact of clinical and imaging-based variables on the DOR of US. RESULTS. Among 820 retrieved studies, 19 studies (1961 examinations) were included. Measuring the CSA of the ulnar nerve at the medial epicondyle with a cutoff value greater than 10-10.5 mm2 had higher sensitivity (80.4%, 95% CI, 75.4-84.7%) than other techniques. Nerve ratios had higher specificity (89.1%, 95% CI, 85.8-91.8%) than other measurements; however, the definition of ratios and cutoff values varied across studies. ROC analysis showed higher diagnostic performance for measuring CSA at the medial epicondyle (AUC, 0.931). The mean CSA value was a significant predictor of the DOR of US (ß coefficient, 0.307 ± 0.074; p < 0.001). Every 1-mm2 larger CSA was associated with a 36% increase in DOR. The diagnostic performance of US was the same in any degree of elbow flexion. CONCLUSION. Measuring CSA of the ulnar nerve at the medial epicondyle has sensitivity and diagnostic performance superior to those of other techniques for the diagnosis of ulnar neuropathy at the elbow.

Updates on Imaging of Liver Tumors.

PURPOSE OF REVIEW: We review advances in imaging of liver tumors, by particularly focusing on the utility of novel imaging in diagnosis and management of these lesions. RECENT FINDINGS: Contrast-enhanced CT and/or MRI are currently utilized for accurate diagnosis of liver tumors, but several ongoing studies are examining the use of other advanced techniques. Novel CT (i.e., dual-energy CT and perfusion CT), MRI (diffusion-weighted imaging, MR elastography, and T1 mapping), and image processing (texture analysis and artificial intelligence-based methods) techniques have emerged and can be used for precise characterization of liver tumors, quantification of treatment responses, and prediction of overall survival rate of patients. Recent advancements in imaging of liver tumors allowed for a precise assessment of tumor features. These evolving technologies can be utilized for applying individualized treatment based on the presence of specific imaging biomarkers.

Epidemiology of facial fractures: incidence, prevalence and years lived with disability estimates from the Global Burden of Disease 2017 study.

BACKGROUND: The Global Burden of Disease Study (GBD) has historically produced estimates of causes of injury such as falls but not the resulting types of injuries that occur. The objective of this study was to estimate the global incidence, prevalence and years lived with disability (YLDs) due to facial fractures and to estimate the leading injurious causes of facial fracture. METHODS: We obtained results from GBD 2017. First, the study estimated the incidence from each injury cause (eg, falls), and then the proportion of each cause that would result in facial fracture being the most disabling injury. Incidence, prevalence and YLDs of facial fractures are then calculated across causes. RESULTS: Globally, in 2017, there were 7 538 663 (95% uncertainty interval 6 116 489 to 9 493 113) new cases, 1 819 732 (1 609 419 to 2 091 618) prevalent cases, and 117 402 (73 266 to 169 689) YLDs due to facial fractures. In terms of age-standardised incidence, prevalence and YLDs, the global rates were 98 (80 to 123) per 100 000, 23 (20 to 27) per 100 000, and 2 (1 to 2) per 100 000, respectively. Facial fractures were most concentrated in Central Europe. Falls were the predominant cause in most regions. CONCLUSIONS: Facial fractures are predominantly caused by falls and occur worldwide. Healthcare systems and public health agencies should investigate methods of all injury prevention. It is important for healthcare systems in every part of the world to ensure access to treatment resources.

Musculoskeletal Radiology Reports: Overlooked or Valuable?

The electronic medical record (EMR) can reveal preferences of clinicians regarding imaging services. We sought to evaluate viewing habits for reports and images of musculoskeletal (MSK) studies by ordering clinicians. We hypothesized that MSK reports are important to clinical management, especially for advanced imaging modalities. We tracked the image and report access of all MSK studies ordered in September 2016 over 8 months using logs of the EMR (Epic Systems, Verona, WI), and by an independent analysis of the institutional PACS (Picture Archiving and Communication Systems) (Carestream Health, Rochester, NY). The time stamps were extracted for when images and reports were viewed. We categorized MSK studies by modality and provider department. We also compared the rates of viewing reports and images among different modalities and departments using the chi-square test. Of the 8143 viewed MSK studies, 7842 (96.3%) reports (with/without images) and 3916 (48.1%) imaging data (with/without reports) were viewed. Viewing reports alone occurred in 4227 (51.9%) studies. CT and MRI reports alone views occurred more often in comparison to radiographs ([482/706; 68.3%] for CT and [981/1713; 57.3%] for MRI vs. [2764/5724; 48.3%] for radiography, p < 0.001). Orthopedists ordered the highest number of MSK studies and viewed reports 99.2% (3216/3242) of the time, including a 54.6% (1770/3242) rate of viewing reports alone and a 44.6% (1446/3242) rate of viewing both reports and images. They viewed images without reports in 0.8% (27/3242) of cases. MSK reports were viewed significantly more frequently than the images across all modalities and all relevant specialties.

Statin Use and Knee Osteoarthritis Outcome Measures according to the Presence of Heberden Nodes: Results from the Osteoarthritis Initiative.

Background The exact contribution of statins to knee osteoarthritis (OA) radiographic outcomes and the characteristics of patients with OA as potential responders to statins remain unclear. Purpose To evaluate the effect of statin use on the incidence of radiographic knee OA (development of Kellgren-Lawrence grade ≥2) and progression of joint space narrowing (JSN) according to the nodal OA status defined according to the presence of Heberden nodes (HNs). Materials and Methods Institutional review boards approved this HIPAA-compliant protocol, and all participants gave informed consent. The Osteoarthritis Initiative (OAI) cohort, which began in 2004 and is ongoing (https://clinicaltrials.gov identifier, NCT00080171), was used to conduct a longitudinal 1:1 propensity score-matched retrospective analysis of prospectively collected data. Participants were classified as having HN-positive or HN-negative findings according to the presence of HNs at baseline physical examination. In each cohort, per-protocol and new-user design were used to match statin initiators (participants who reported ≤1 year of statin use before enrollment) and nonusers (participants who reported no statin use before enrollment) for variables that potentially contributed to confounding by indication bias. Participants were followed up annually over 8 years. Any associations between statin use and longitudinal knee OA radiographic incidence, JSN progression, or nonacceptable symptomatic state incidence was assessed by using hazard ratios (HRs) of Cox regression. Results In the longitudinal analysis, there were 832 knees of 602 participants (pair-matched knees of statin initiators and nonusers) in the HN-positive cohort (mean age, 64.7 years ± 8.0 [standard deviation]; 377 patients were female [62.6%]) and 386 knees of 285 participants in the HN-negative cohort (mean age, 58.9 years ± 8.2; 144 patients were female [50.5%]). In the HN-positive cohort, statin users had 46% lower risk of JSN progression in comparison with matched nonusers (HR, 0.54; 95% confidence interval [CI]: 0.36, 0.93; P = .02). In contrast, in the HN-negative cohort, statin use had no association with radiographic JSN progression (HR, 1.37; [95% CI: 0.74, 2.53]; P = .32). Conclusion Statin use was associated with reduced risk of radiographic knee osteoarthritis joint space narrowing progression in patients with nodal osteoarthritis. © RSNA, 2019 Online supplemental material is available for this article.

Activation of ATP-sensitive K-channel promotes the anticonvulsant properties of cannabinoid receptor agonist through mitochondrial ATP level reduction.

Cannabinoid receptor (CBR) agonist could act as a protective agent against seizure susceptibility in animal models of epilepsy. Studies have shown that potassium channels could play a key role in ameliorating neuronal excitability. In this study, we attempted to evaluate how CBRs and Adenosine Tri-Phosphate (ATP)-sensitive potassium channels collaborate to affect seizure susceptibility by changing the clonic seizure threshold (CST). We used male Naval Medical Research Institute (NMRI) mice and treated them with the following drugs: cromakalim (a potassium channel opener, 10 µg/kg), glibenclamide (a potassium channel blocker, 0.03 and 1 mg/kg), 0.5 mg/kg of AM-251 (a selective CB1 antagonist), AM-630 (a selective CB2 antagonist), and 0.5, 3, and 10 mg/kg of WIN 55,212-2 (a nonselective agonist of CBRs); and CST was appraised after each type of administration. Also, we evaluated the ATP level of the hippocampus in each treatment to clarify the interaction between the cannabinoid system and potassium channel. Our results showed that administration of WIN 55,212-2 at 10 mg/kg significantly increased CST (P < 0.001). This change could be reversed by using AM-251(P < 0.001) but not AM-630. Also, either cromakalim (10 µg/kg) or glibenclamide (0.03 and 1 mg/kg) could not significantly affect the CST. In addition, glibenclamide (1 mg/kg) could reverse the anticonvulsant effect of WIN 55,212-2 (10 mg/kg) on CST (P < 0.001). However, the anticonvulsant effect was observed when cromakalim (10 µg/kg) was added to WIN 55,212-2 at its subeffective dose (3 mg/kg) in comparison to single-treated animals. Interestingly, we observed that CB1 agonist could significantly decrease ATP level. In conclusion, CB1 agonist accomplishes at least a part of its anticonvulsant actions through ATP-sensitive potassium channels, probably by decreasing the mitochondrial ATP level to open the potassium channel to induce its anticonvulsant effect.

Kinematic Analysis of the Distal Radioulnar Joint in Asymptomatic Wrists Using 4-Dimensional Computed Tomography-Motion Pattern and Interreader Reliability.

PURPOSE: The aim of this study was to determine the normal measurement values and interobserver performance of the distal radioulnar joint during wrist pronation-supination using 4-dimensional computed tomography (CT). METHODS: Four-dimensional CT examinations were performed on the asymptomatic contralateral wrists of 10 patients with unilateral chronic wrist pain. Measurements were conducted using the modified radioulnar (mRU) line and epicenter (Epi) methods. Volar subluxation of the ulnar head was demonstrated with negative values. Wilcoxon rank sum test was used to determine the measurement changes. Interobserver agreements were assessed using interclass correlation coefficients. RESULTS: In pronation, mRU line measurements (median, 0.09; interquartile range, 0-0.15) were significantly larger than in supination (median, -0.1; interquartile range, -0.18 to 0; P = 0.008).The Epi measurements were not significantly different in pronation (median, 0.03; interquartile range, 0.01-0.07) and supination (median, 0.06; interquartile range, 0.01-0.1; P = 0.799). There was an excellent inter-observer agreement between the two readers using mRU and Epi methods in pronation (0.982, 0.898), midpoint (0.994, 0.827) and supination (0.989, 0.972) positions, respectively. CONCLUSIONS: Using 4-dimensional CT examination, distal radioulnar joint kinematics in asymptomatic wrists demonstrate excellent interobserver agreements with increased volar ulnar subluxation with supination as detected using mRU, but not the Epi method.

Role of toll-like receptors in inflammatory bowel disease.

Inflammatory bowel disease (IBD) is the chronic inflammation of the gastrointestinal tract. Recently, studies of the interplay between the adaptive and innate immune responses have provided a better understanding of the immunopathogenesis of inflammatory disorders such as IBD, as well as identification of novel targets for more potent interventions. Toll-like receptors (TLRs) are a class of proteins that play a significant role in the innate immune system and are involved in inflammatory processes. Activation of TLR signal transduction pathways lead to the induction of numerous genes that function in host defense, including those for inflammatory cytokines, chemokines, and antigen presenting molecules. It was proposed that TLR mutations and dysregulation are major contributing factors to the predisposition and susceptibility to IBD. Thus, modulating TLRs represent an innovative immunotherapeutic approach in IBD therapy. This article outlines the role of TLRs in IBD, focusing on both animal and human studies; the role of TLR-targeted agonists or antagonists as potential therapeutic agents in the different stages of the disease is discussed.

Superolateral Hoffa's fat pad (SHFP) oedema and patellar cartilage volume loss: quantitative analysis using longitudinal data from the Foundation for the National Institute of Health (FNIH) Osteoarthritis Biomarkers Consortium.

OBJECTIVES: To determine the association of superolateral Hoffa's fat pad (SHFP) oedema and patellofemoral joint structural damage in participants of Foundation for the National Institute of Health Osteoarthritis Biomarkers Consortium study. METHODS: Baseline and 24-month MRIs of 600 subjects were assessed. The presence of SHFP oedema (using 0-3 grading scale) and patellar morphology metrics were determined using baseline MRI. Quantitative patellar cartilage volume and semi-quantitative MRI osteoarthritis knee score (MOAKS) variables were extracted. The associations between SHFP oedema and patellar cartilage damage, bone marrow lesion (BML), osteophyte and morphology were evaluated in cross-sectional model. In longitudinal analysis, the associations between oedema and cartilage volume loss (defined using reliable change index) and MOAKS worsening were evaluated. RESULTS: In cross-sectional evaluations, the presence of SHFP oedema was associated with simultaneous lateral patellar cartilage/BML defects and inferior-medial patellar osteophyte size. A significant positive correlation between the degree of patella alta and SHFP oedema was detected (r = 0.259, p < 0.001). The presence of oedema was associated with 24-month cartilage volume loss (odds ratio (OR) 2.11, 95% confidence interval 1.46-3.06) and medial patellar BML size (OR 1.92 (1.15-3.21)) and number (OR 2.50 (1.29-4.88)) worsening. The optimal cut-off value for the grade of baseline SHFP oedema regarding both presence and worsening of patellar structural damage was ≥ 1 (presence of any SHFP hyperintensity). CONCLUSIONS: The presence of SHFP oedema could be considered as a predictor of future patellar cartilage loss and BML worsening, and an indicator of simultaneous cartilage, BML and osteophyte defects. KEY POINTS: • SHFP oedema was associated with simultaneous lateral patellar OA-related structural damage. • SHFP oedema was associated with longitudinal patellar cartilage loss over 24 months. • SHFP oedema could be considered as indicator and predictor of patellar OA.

Tibial tuberosity to trochlear groove distance and its association with patellofemoral osteoarthritis-related structural damage worsening: data from the osteoarthritis initiative.

OBJECTIVES: To determine whether the tibial tuberosity-to-trochlear groove (TT-TG) distance is associated with concurrent patellofemoral joint osteoarthritis (OA)-related structural damage and its worsening on 24-month follow-up magnetic resonance imaging (MRI) in participants in the Osteoarthritis Initiative (OAI). METHODS: Six hundred subjects (one index knee per participant) were assessed. To evaluate patellofemoral OA-related structural damage, baseline and 24-month semiquantitative MRI Osteoarthritis Knee Score (MOAKS) variables for cartilage defects, bone marrow lesions (BMLs), osteophytes, effusion, and synovitis were extracted from available readings. The TT-TG distance was measured in all subjects using baseline MRIs by two musculoskeletal radiologists. The associations between baseline TT-TG distance and concurrent baseline MOAKS variables and their worsening in follow-up MRI were investigated using regression analysis adjusted for variables associated with tibiofemoral and patellofemoral OA. RESULTS: At baseline, increased TT-TG distance was associated with concurrent lateral patellar and trochlear cartilage damages, BML, osteophytes, and knee joint effusion [cross-sectional evaluations; overall odds ratio 95% confidence interval (OR 95% CI): 1.098 (1.045-1.154), p < 0.001]. In the longitudinal analysis, increased TT-TG distance was significantly related to lateral patellar and trochlear cartilage, BML, and joint effusion worsening (overall OR 95% CI: 1.111 (1.056-1.170), p < 0.001). CONCLUSIONS: TT-TG distance was associated with simultaneous lateral patellofemoral OA-related structural damage and its worsening over 24 months. Abnormally lateralized tibial tuberosity may be considered as a risk factor for future patellofemoral OA worsening. KEY POINTS: • Excessive TT-TG distance on MRI is an indicator/predictor of lateral-patellofemoral-OA. • TT-TG is associated with simultaneous lateral-patellofemoral-OA (6-17% chance-increase for each millimeter increase). • TT-TG is associated with longitudinal (24-months) lateral-patellofemoral-OA (5-15% chance-increase for each millimeter).

Acute foot-shock stress decreased seizure susceptibility against pentylenetetrazole-induced seizures in mice: Interaction between endogenous opioids and cannabinoids.

BACKGROUND: Stressful conditions affect the brain's neurotransmission and neural pathways that are involved in seizure susceptibility. Stress alters the intensity and/or frequency of seizures. Although evidence indicates that chronic stress exerts proconvulsant effects and acute stress has anticonvulsant properties, the underlying mechanisms which mediate these effects are not well understood. In the present study, we assessed the role of endogenous opioids, endocannabinoids, as well as functional interaction between opioid and cannabinoid systems in the anticonvulsant effects of acute foot-shock stress (FSS) against pentylenetetrazole (PTZ)-induced seizures in mice. METHODS: Prolonged intermittent FSS was chosen as an acute stress model. Seizure threshold was determined after 30 min of stress induction in male Naval Medical Research Institute (NMRI) mice (20-30 g). Opioid and cannabinoid receptor antagonists were administered before animal placement in the FSS apparatus. RESULTS: Acute FSS significantly decreased seizure susceptibility in animals. The administration of the cannabinoid receptor 1 (CB1) antagonist, AM251, completely blocked the anticonvulsant effect of acute FSS at the doses of 1 pg/kg-100 µg/kg but not at 1 fg/kg. Pretreatment with the nonspecific opioid receptor antagonist, naltrexone (NTX), significantly inhibited the anticonvulsant effects of acute FSS at 1 and 2 mg/kg but not at 0.3 mg/kg. However, coadministration of the subeffective doses of AM251 (1 fg/kg) and NTX (0.3 mg/kg) reversed the anticonvulsant effects of acute FSS. CONCLUSIONS: Opioid and cannabinoid systems are involved in the anticonvulsant effects of acute FSS, and these neurotransmission systems interact functionally in response to acute FSS.