Initially described, in 1948, as a tumor that could be mistaken with chondrosarcoma at histopathology, chondromyxoid fibroma is now a well-recognized entity. Surface-type chondromyxoid fibroma, ...however, remains an extremely rare occurrence. We present a case of a 55-year-old woman, who experienced right arm pain for 5 years. After unsuccessful treatment for presumed thoracic outlet syndrome, MRI revealed a large mass abutting the anteromedial cortex of the distal humeral diaphysis in a subperiosteal location. Further characterization was made with radiography, CT, and bone scan, which were followed by ultrasound-guided biopsy. Although histopathologic features were suggestive of chondromyxoid fibroma, the diagnosis remained somewhat uncertain initially due to the very unusual location involving the diaphysis of the humerus. Surgical resection was performed, and subsequent histopathologic analysis confirmed the diagnosis of chondromyxoid fibroma. Despite being a rare entity, surface-type chondromyxoid fibroma would need to be considered in the differential when dealing with expansile surface diaphyseal lesions.
The aim of this study was to measure the association between exposure to commonly used oral osteoarthritis (OA) therapies and relevant confounding risk factors on the occurrence of knee replacement ...(KR), using the Osteoarthritis Initiative (OAI) database.
In this nested case-control design study, participants who had a KR after cohort entry were defined as "cases" and were matched with up to four controls for age, gender, income, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, Kellgren-Lawrence grade, and duration of follow up. Exposure to oral OA therapies (acetaminophen, non-steroidal anti-inflammatory drugs (NSAIDs), cyclooxygenase-2 (COX-2) inhibitors, narcotics, and glucosamine/chondroitin sulfate) was determined within the 3 years prior to the date of the KR. Conditional regression analyses were performed to estimate the association between KR and exposure to oral OA therapies and other potential confounding risk factors.
A total of 218 participants who underwent a KR (cases) were matched to 540 controls. The median time to KR was 4.3 years among cases. The majority in both groups were Caucasian with mean age of 69 years and 61% were female. Numerically, cases were more exposed to acetaminophen, NSAIDs, and COX-2 inhibitors. Exposure to narcotics and glucosamine/chondroitin sulfate was relatively similar between cases and controls. No significant association was found between the occurrence of KR and exposure to any of the oral OA therapies within the 3 years prior to KR. A significantly higher occurrence of KR was found in Caucasian subjects (OR 1.84; 95% CI, 1.13-2.99; p = 0.015) and subjects with body mass index (BMI) ≥ 27 kg/m
(OR 1.65; 95% CI, 1.06-2.58; p = 0.027).
This study provides evidence that the main risk factors leading to KR are disease severity, symptoms and high BMI. Importantly, exposure to oral OA therapies was not associated with the occurrence of KR.
The weight of recommendation for intra-articular therapies such as hyaluronic acid injections varies from one set of guidelines to another, and they have not yet reached unanimity with respect to the ...usefulness of intra-articular hyaluronic acid (IAHA) injections for the symptomatic treatment of knee osteoarthritis (OA). Among the reasons for the controversy is that the current literature provides inconsistent results and conclusions about such treatment. This study aimed at identifying determinants associated with a better response to IAHA treatment in knee OA.
Subjects were selected from the Osteoarthritis Initiative database. Participants were subjects who had radiographic OA, received one IAHA treatment, and had data on demographics and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores at visits before (T0) and after (T1; within 6 months) treatment. Pain was analyzed for demographic, clinical, and imaging characteristics at T0 and change over time (T0 to T1). Subjects with WOMAC pain > 0 at T0 were subdivided into Low, Moderate, and High pain groups based on tertile analysis. Further analyses were done with the High pain group (score ≥ 8), which was divided into responders (improvement in pain ≥ 20%) and nonresponders (unchanged or worsening of pain).
Participants (n = 310) received a total of 404 treatments (one per knee). In the Low and Moderate pain groups vs the High pain group, participants had significantly lower score at T0 (p < 0.001), and the Low vs High pain group had significantly lower BMI (p = 0.002), greater joint space width (JSW) (p = 0.010) and knee cartilage volume (p ≤ 0.009), and smaller synovial effusion (p = 0.033). In the High pain group, responders vs nonresponders were usually younger (p = 0.014), with greater cartilage volume in the medial compartment (p = 0.046), a trend toward greater JSW, and a significant improvement in all WOMAC scores (p < 0.001), while nonresponders showed worsening of symptoms.
This study identified reliable predictive determinants that can distinguish patients who could best benefit from IAHA treatment: high levels of knee pain, younger, and less severe structural damage. These could be implemented in clinical practice as a useful guide for physicians.
We present the first statistical analysis of exoplanet direct imaging surveys combining adaptive optics (AO) imaging at small separations with deep seeing-limited observations at large separations ...allowing us to study the entire orbital separation domain from 5 to 5000 au simultaneously. Our sample of 344 stars includes only confirmed members of nearby young associations and is based on all AO direct-imaging detection limits readily available online, with addition of our own previous seeing-limited surveys. Assuming that the companion distribution in mass and a semimajor axis follows a power-law distribution and adding a dependence on the mass of the host star, such as , we constrain the parameters to obtain , , and at a 68% confidence level, and we obtain for the overall planet occurrence rate for companions with masses between 1 and 20 in the range of 5-5000 au. Thus, we find that occurrence of companions is negatively correlated with a semimajor axis and companion mass (marginally) but is positively correlated with the stellar host mass. Our inferred mass distribution is in good agreement with other distributions found previously from direct imaging surveys for planets and brown dwarfs, but is shallower as a function of mass than the distributions inferred by radial velocity surveys of gas giants in the 1-3 au range. This may suggest that planets at these wide and very wide separations represent the low-mass tail of the brown dwarfs and stellar companion distribution rather than an extension of the distribution of the inner planets.
There is an obvious need to identify biomarkers that could predict patient response to an osteoarthritis (OA) treatment. This post hoc study explored in a 2-year randomized controlled trial in ...patients with knee OA, the likelihood of some serum biomarkers to be associated with a better response to chondroitin sulfate in reducing cartilage volume loss.
Eight biomarkers were studied: hyaluronic acid (HA), C reactive protein (CRP), adipsin, leptin, N-terminal propeptide of collagen IIα (PIIANP), C-terminal crosslinked telopeptide of type I collagen (CTX-1), matrix metalloproteinase-1 (MMP-1), and MMP-3. Patients were treated with chondroitin sulfate (1200 mg/day; n = 57) or celecoxib (200 mg/day; n = 62). Serum biomarkers were measured at baseline. The cartilage volume at baseline and its loss at 2 years were assessed by quantitative magnetic resonance imaging (MRI). Statistical analysis included analysis of covariance.
As data from the original MOSAIC trial showed no differences in cartilage volume and loss in the lateral compartment of the knee joint between the two treatment groups in any comparison, only the medial compartment and its subregions were studied. Stratification according to the median biomarker levels was used to discriminate treatment effect. In patients with levels of biomarkers of inflammation (HA, leptin and adipsin) lower than the median, those treated with chondroitin sulfate demonstrated less cartilage volume loss in the medial compartment, condyle, and plateau (p ≤ 0.047). In contrast, patients treated with chondroitin sulfate with higher levels of MMP-1 and MMP-3, biomarkers of cartilage catabolism, had less cartilage volume loss in the medial compartment, condyle, and plateau (p ≤ 0.050). Patients with higher levels of PIIANP and CTX-1, biomarkers related to collagen anabolism and bone catabolism, respectively, had reduced cartilage volume loss in the medial condyle (p ≤ 0.026) in the chondroitin sulfate group.
This study is suggestive of a potentially greater response to chondroitin sulfate treatment on cartilage volume loss in patients with knee OA with low level of inflammation and/or greater level of cartilage catabolism.
This is a post hoc study. Original trial registration: ClinicalTrials.gov, NCT01354145 . Registered on 13 May 2011.
Abstract Objective In the perspective of personalized management of osteoarthritis (OA), a clinically relevant concern is the impact of meniscal extrusion (Ext) on response to treatment. This study ...aimed at determining the effects of conventional OA pharmacological treatments and those of the combination of glucosamine and chondroitin sulfate (Glu/CS) on knee structural changes in the presence or absence of Ext, using data from the progression cohort of the Osteoarthritis Initiative. Methods In this longitudinal study, knee OA participants were stratified based on whether (+) or not (−) they received analgesics/NSAIDs (+ and −analgesics/NSAIDs) and/or Glu/CS (+ and −Glu/CS) for 24 consecutive months and on the presence (Ext+) or absence (Ext−) of medial meniscal extrusion at baseline. The main outcomes were knee structural changes including the loss of joint space width (JSW) and cartilage volume loss measured by quantitative MRI. Results In both − and +analgesics/NSAIDs groups ( n = 300 each), the Ext+ participants had more-advanced disease at baseline (T0) and more JSW loss and cartilage volume loss in the medial compartment ( p ≤ 0.003, univariate; p ≤ 0.049, multivariate analyses) at both 12 (T12) and 24 (T24) months compared to Ext− participants. In the −analgesics/NSAIDs group, Ext+ participants taking Glu/CS had significantly less cartilage volume loss in the medial plateau at T24 ( p ≤ 0.010, univariate and multivariate analyses). In the +analgesics/NSAIDs group at T24, Ext− participants taking Glu/CS had less cartilage volume loss in the global ( p ≤ 0.002, univariate and multivariate analyses) and medial and lateral plateaus ( p = 0.034 and p = 0.013, respectively, multivariate analysis). No significant difference in JSW loss was found between the groups. Conclusion This study is the first to demonstrate, using qMRI, that meniscal extrusion can modify the response to Glu/CS treatment in knee OA patients, depending on the severity of the disease.
Pain in osteoarthritis (OA) has been classically attributed to joint structural damage. Disparity between the degree of radiographic structural damage and the severity of symptoms implies that ...factors other than the joint pathology itself contribute to the pain. Peripheral and central sensitization have been suggested as two of the underlying mechanisms that contribute to pain in OA. The aim of this study was to explore in symptomatic knee OA patients, the structural changes assessed by magnetic resonance imaging (MRI) that could be used as markers of neuropathic pain (NP).
This cross-sectional observational pilot study included 50 knee OA patients with moderate to severe pain (VAS ≥40) in the target knee. The presence of NP was determined based on the PainDETECT questionnaire. Among the 50 patients included, 25 had PainDETECT score ≤12 (unlikely NP), 9 had PainDETECT score between 13 and 18 (uncertain NP) and 16 had PainDETECT score ≥19 (likely NP). WOMAC, PainDETECT, and VAS pain scores as well as knee MRI were assessed.
Data showed no significant difference in demographic characteristics between the three groups. However, a positive and statistically significant association was found between the WOMAC pain (P <0.001), function (P <0.001), stiffness (P = 0.007) and total (P <0.001) scores as well as higher VAS pain score (P = 0.023), and PainDETECT scores. Although no difference was found in the cartilage volume between groups, the presence of meniscal extrusion in both medial (P = 0.006) and lateral (P = 0.023) compartments, and presence of meniscal tears in the lateral compartment (P = 0.011), were significantly associated with increasing PainDETECT score. Moreover, the presence of bone marrow lesions in the lateral plateau and the extent of the synovial membrane thickness in the lateral recess were associated with increasing PainDETECT scores (P = 0.032, P = 0.027, respectively).
In this study, meniscal lesions, particularly extrusion, were found to be among the strongest risk factors for NP in knee OA patients.
ClinicalTrials.gov NCT01733277. Registered 16 November 2012.
Objective
To investigate the diagnostic performance of preoperative MRI in evaluating posterolateral corner (PLC) structures after acute knee dislocation (KD) and determine the correlation of MRI ...with operative findings for grading structure integrity.
Methods
Acute knee (femorotibial) dislocations between 2005 and 2020 with preoperative MRI and surgical posterolateral corner repair were identified from a single academic institution. From MRI, integrity was evaluated for PLC structures: lateral collateral ligament (LCL), popliteus tendon (PT), biceps femoris tendon (BFT), and ligamento-capsular complex (LCC). Frequency of injury to each structure and number of PLC structures torn in each case were tabulated. Diagnostic performance of MRI was determined using surgery as the reference standard. Correlation between MRI and surgery for each PLC structure was determined using kappa.
Results
Thirty-nine KD cases (19 right) in 39 patients (28 male) were included, with mean age of 33 years. Mechanism of injury was as follows: high energy 52%, low energy 38%, ultra-low energy 10%. LCL was most frequently torn, in 95% (37/39) of cases. Most commonly, three of four PLC structures were torn in 54% (21/39) of cases. Diagnostic accuracy of MRI was high for LCL 95%, BFT 87%, PT 82%, and LCC 92%. Correlation between MRI and surgical findings was variable: substantial for BFT, moderate for LCL and PT, and fair for LCC.
Conclusion
MRI has high accuracy for detecting tears of posterolateral corner stabilizers in the setting of acute KD. However, for grading structure integrity, the correlation of MRI with surgical findings is variable, ranging from fair to substantial.
Key Points
• In acute knee dislocation, MRI has high diagnostic accuracy for detecting tears of posterolateral corner (PLC) structures.
• Preoperative MRI should be considered by orthopedic surgeons when there is clinical concern for posterolateral corner instability following acute knee dislocation.
• Although MRI is valuable in the preoperative investigation of knee dislocation, clinical assessment and intraoperative exploration may still be required for definitive diagnosis.
Wide low-mass substellar companions are known to be very rare among low-mass stars, but appear to become increasingly common with increasing stellar mass. However, B-type stars, which are the most ...massive stars within ~150 pc of the Sun, have not yet been examined to the same extent as AFGKM-type stars in that regard. In order to address this issue, we launched the ongoing B-star Exoplanet Abundance Study (BEAST) to examine the frequency and properties of planets, brown dwarfs, and disks around B-type stars in the Scorpius-Centaurus (Sco-Cen) association; we also analyzed archival data of B-type stars in Sco-Cen. During this process, we identified a candidate substellar companion to the B9-type spectroscopic binary HIP 79098 AB, which we refer to as HIP 79098 (AB)b. The candidate had been previously reported in the literature, but was classified as a background contaminant on the basis of its peculiar colors. Here we demonstrate that the colors of HIP 79098 (AB)b are consistent with several recently discovered young and low-mass brown dwarfs, including other companions to stars in Sco-Cen. Furthermore, we show unambiguous common proper motion over a 15-yr baseline, robustly identifying HIP 79098 (AB)b as a bona fide substellar circumbinary companion at a 345 ± 6 AU projected separation to the B9-type stellar pair. With a model-dependent mass of 16–25 MJup yielding a mass ratio of <1%, HIP 79098 (AB)b joins a growing number of substellar companions with planet-like mass ratios around massive stars. Our observations underline the importance of common proper motion analysis in the identification of physical companionship, and imply that additional companions could potentially remain hidden in the archives of purely photometric surveys.
PDF
