Patterns of variation among baseline femoral and tibial cartilage thickness and clinical features: Data from the osteoarthritis initiative.

Objective: To employ novel methodologies to identify phenotypes in knee OA based on variation among three baseline data blocks: 1) femoral cartilage thickness, 2) tibial cartilage thickness, and 3) participant characteristics and clinical features. Methods: Baseline data were from 3321 Osteoarthritis Initiative (OAI) participants with available cartilage thickness maps (6265 knees) and 77 clinical features. Cartilage maps were obtained from 3D DESS MR images using a deep-learning based segmentation approach and an atlas-based analysis developed by our group. Angle-based Joint and Individual Variation Explained (AJIVE) was used to capture and quantify variation, both shared among multiple data blocks and individual to each block, and to determine statistical significance. Results: Three major modes of variation were shared across the three data blocks. Mode 1 reflected overall thicker cartilage among men, those with higher education, and greater knee forces; Mode 2 showed associations between worsening Kellgren-Lawrence Grade, medial cartilage thinning, and worsening symptoms; and Mode 3 contrasted lateral and medial-predominant cartilage loss associated with BMI and malalignment. Each data block also demonstrated individual, independent modes of variation consistent with the known discordance between symptoms and structure in knee OA and reflecting the importance of features such as physical function, symptoms, and comorbid conditions independent of structural damage. Conclusions: This exploratory analysis, combining the rich OAI dataset with novel methods for determining and visualizing cartilage thickness, reinforces known associations in knee OA while providing insights into the potential for data integration in knee OA phenotyping.

Bone bruising severity after anterior cruciate ligament rupture predicts elevation of chemokine MCP-1 associated with osteoarthritis.

PURPOSE: Anterior cruciate ligament rupture is associated with characteristic bone contusions in approximately 80% of patients, and these have been correlated with higher pain scores. Bone bruising may indicate joint damage that increases inflammation and the likelihood of posttraumatic osteoarthritis. We sought to characterize the severity of bone bruising following acute anterior cruciate ligament injury and determine if it correlates with synovial fluid and serum levels of the proinflammatory chemokine monocyte chemoattractant protein-1 associated with posttraumatic osteoarthritis. METHODS: This was a retrospective analysis of data collected prospectively from January 2014 through December 2016. All patients who sustained an acute ligament rupture were evaluated within 15 days of injury, obtained a magnetic resonance imaging study, and underwent bone-patellar-tendon-bone autograft reconstruction were offered enrollment. The overall severity of bone bruising on magnetic resonance imaging was graded (sum of 0-3 grades in 13 sectors of the articular surfaces). Serum and synovial fluid levels of monocyte chemoattractant protein-1 were measured within 14 days of injury, and serum levels were again measured 6 and 12 months following surgery. Separate univariate linear regression models were constructed to determine the association between monocyte chemoattractant protein-1 and bone bruising severity at each time point. RESULTS: Forty-eight subjects were included in this study. They had a mean age of 21.4 years and were 48% female. Median overall bone bruising severity was 5 (range 0-14). Severity of bone bruising correlated with higher synovial fluid concentrations of monocyte chemoattractant protein-1 preoperatively (R2 = 0.18, p = 0.009) and with serum concentrations at 12 months post-reconstruction (R2 = 0.12, p = 0.04). CONCLUSIONS: The severity of bone bruising following anterior cruciate ligament rupture is associated with higher levels of the proinflammatory cytokine monocyte chemoattractant protein-1 in synovial fluid acutely post-injury and in serum 12-months following anterior cruciate ligament reconstruction. This suggests that severe bone bruising on magnetic resonance imaging after ligament rupture may indicate increased risk for persistent joint inflammation and posttraumatic osteoarthritis. LEVEL OF EVIDENCE: III - retrospective cohort study.

Talar and Subtalar T1ρ Relaxation Times in Limbs with and without Chronic Ankle Instability.

OBJECTIVE: The primary aim was to determine differences in talocrural and subtalar joint (STJ) articular cartilage composition, using T1ρ magnetic resonance imaging (MRI) relaxation times, between limbs in individuals with unilateral chronic ankle instability (CAI) and compare with an uninjured control. Our secondary purpose was to determine the association between talocrural and STJ composition in limbs with and without CAI. DESIGN: T1ρ MRI relaxation times were collected on 15 CAI (11 females, 21.13 ± 1.81 years, body mass index [BMI] = 23.96 ± 2.74 kg/m2) and 15 uninjured control individuals (11 females, 21.07 ± 2.55 years, BMI = 24.59 ± 3.44 kg/m2). Talocrural cartilage was segmented manually to identify the overall talar dome. The SJT cartilage was segmented manually to identify the anterior, medial, and posterior regions of interest consistent with STJ anatomical articulations. For each segmented area, a T1ρ relaxation time mean and variability value was calculated. Greater T1ρ relaxation times were interpreted as decreased proteoglycan content. RESULTS: Individuals with CAI demonstrated a higher involved limb talocrural T1ρ mean and variability relative to their contralateral limb (P < 0.05) and the healthy control limb (P < 0.05). The CAI-involved limb also had a higher posterior STJ T1ρ mean relative to the healthy control limb (P < 0.05). In healthy controls (P < 0.05), but not the CAI-involved or contralateral limbs (p>0.05), talocrural and posterior STJ composition measures were positively associated. CONCLUSIONS: Individuals with CAI have lower proteoglycan content in both the talocrural and posterior STJ in their involved limbs relative to the contralateral and a healthy control limb. Cartilage composition findings may be consistent with the early development of posttraumatic osteoarthritis.

Ultrasonographic Measures of Talar Cartilage Thickness Associate with Magnetic Resonance-Based Measures of Talar Cartilage Volume.

Our primary goal was to quantify associations between ultrasonographic (US) measurements of talar cartilage apparent thickness and magnetic resonance (MR)-based measures of talar cartilage volume in a heterogeneous sample of those with and without chronic ankle instability. Cartilage volume from MR and normalized cross-sectional area (CSA) and thickness from a transverse US image of the talar cartilage were calculated after 30 min of unloading. Overall talar and region of interest-specific morphology measures (i.e., volume, normalized CSA, thickness) were submitted for statistical analysis. Overall US-normalized CSA positively associated with the overall talar MR volume (r = 0.641, p < 0.001). Medial (r = 0.673, p < 0.001) and lateral US-normalized CSA (r = 0.584, p = 0.001) positively associated with MR volume in the anteromedial and anterolateral MR region of interest, respectively. No differences in US-based normalized CSA, thickness (p > 0.481) or MR-based volume (p > 0.287) were noted between the groups. US appears to be a clinically accessible and cost-effective method for evaluating average ankle cartilage apparent thickness.

Effects of a knee valgus unloader brace on medial femoral articular cartilage deformation following walking in varus-aligned individuals.

BACKGROUND: Knee varus alignment may increase loading in the medial tibiofemoral compartment, which can increase strain on the articular cartilage. Knee valgus unloader braces seek to reduce loading through the medial femoral compartment, but their effects on cartilage characteristics during dynamic tasks have not been evaluated. OBJECTIVE: To determine the effects of a knee valgus unloader brace on medial femoral articular cartilage deformation following a single 5000-step walking protocol in individuals with varus-knee alignment. METHODS: Twenty-four healthy individuals (63% female, BMI = 22 ±â€¯3 kg/m2, age = 21 ±â€¯3 years) completed two testing sessions (braced and unbraced) separated by one week. During both sessions, femoral cartilage ultrasound images were acquired prior to and following a 5000-step treadmill walking protocol at self-selected speed. Percent change scores in medial cartilage cross-sectional area (MCCA) were calculated and used as the primary outcome, and compared between the braced and unbraced conditions. RESULTS: There was no difference in percent change of MCCA between conditions (braced = -2.77%, unbraced = -3.15%, p = 0.699). Individuals whose cartilage deformed more than a previously established minimal detectable change (MDC ≥ 1.58 mm2) deformed less during the braced condition (braced = -2.94%, unbraced = -6.34%, p = 0.028), compared to individuals who did not deform greater than the MDC (n = 15, braced = -2.67%, unbraced = -1.23%, p = 0.210). CONCLUSIONS: There was no significant difference in MCCA percent change between the braced and unbraced conditions across the entire cohort; yet a valgus unloader braces may serve as a potential intervention strategy for reducing articular cartilage deformation in certain varus-aligned individuals who normally undergo measurable deformation during walking.

Enhancement of Musculoskeletal Radiology Resident Education with the Use of an Individual Smart Portable Ultrasound Device (iSPUD).

RATIONALE AND OBJECTIVES: Many medical specialties have incorporated portable ultrasound into their educational curriculum. Our objective was to determine the utility of an individual smart portable ultrasound device (iSPUD) as an educational tool in resident and fellowship Musculoskeletal Radiology training. MATERIALS AND METHODS: After Institutional Review Board approval, volunteer radiology trainees were instructed to use the iSPUD (Philips Lumify ultrasound probe and Samsung Galaxy Tab S2 8 inch tablet), asked to identify 10 wrist structures with the iSPUD and completed a Likert scale-based, pretest survey. Trainees were then given the iSPUD for 3 days of independent scanning practice. Afterward, trainees were asked to identify the same 10 wrist structures with the iSPUD and to complete a Likert scale-based, post-test survey. RESULTS: Twenty trainees volunteered to participate. Trainee performance on the 10-wrist structure identification test with the iSPUD resulted in a pretest mean number correct of 2.5 ± 2.16 and a post-test mean number correct of 9.85 ± 0.37 (p < 0.001). On the pretest survey, 68.42% (13/20) had never performed and 42.11% (8/20) had never interpreted a musculoskeletal ultrasound. On the post-test survey, 18/20 (94.74%) strongly agreed that access to an iSPUD would improve their ability to perform musculoskeletal ultrasound, improve ultrasound-guided interventional skills, and help them become better Radiologists. CONCLUSION: The use of an iSPUD as a tool in Musculoskeletal Radiology resident and fellow education can improve clinical ultrasound skills, build trainee technical confidence during diagnostic ultrasound procedures, and help trainees achieve their goal of becoming a competent Radiologist.

Quadriceps Rate of Torque Development and Disability in Persons With Tibiofemoral Osteoarthritis.

Background Declines in the ability to rapidly generate quadriceps muscle torque may underlie disability in individuals with tibiofemoral osteoarthritis. Objective To determine whether quadriceps rate of torque development (RTD) predicts self-reported disability and physical performance outcomes in individuals with tibiofemoral osteoarthritis. Methods This controlled laboratory, cross-sectional study assessed quadriceps strength and RTD in 76 individuals (55% female; mean ± SD age, 61.83 ± 7.11 years) with symptomatic and radiographic tibiofemoral osteoarthritis. Early (0-50 milliseconds), late (100-200 milliseconds), and overall peak RTDs were quantified in the symptomatic (involved) and contralateral limbs and used to calculate bilateral average values. Disability was assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function subscale and 3 physical performance tests, including the (1) 20-m fast-paced walk, (2) 30-second chair stand, and (3) timed stair climb. Separate univariate regression models were used to determine the unique associations among measures of quadriceps RTD, WOMAC function score, and physical performance outcomes after accounting for quadriceps strength (change in R2). Results Greater involved-side late RTD and greater bilateral average early RTD were associated with faster walking (change in R2 = 0.05, P = .013 and change in R2 = 0.05, P = .043, respectively). Greater bilateral average late RTD was associated with faster walking (change in R2 = 0.20, P<.001) and faster stair climb (change in R2 = 0.11, P = .001). No quadriceps RTD variable was significantly associated with WOMAC function score (change in R2 range, <0.01-0.017). Conclusion Involved-limb quadriceps RTD was weakly associated with physical performance outcomes, but not self-reported disability, in individuals with tibiofemoral osteoarthritis. Bilateral average quadriceps RTD was moderately associated with walking speed. Level of Evidence Prognosis, level 2b. J Orthop Sports Phys Ther 2018;48(9):694-703. Epub 22 May 2018. doi:10.2519/jospt.2018.7898.

Investigating magnetic susceptibility of human knee joint at 7 Tesla.

PURPOSE: To evaluate the magnetic susceptibility properties of different anatomical structures within the knee joint using quantitative susceptibility mapping (QSM). METHODS: A collagen tissue model was simulated and ex vivo animal cartilage experiments were conducted at 9.4 Tesla (T) to evaluate the B0 orientation-dependent magnetic susceptibility contrast observed in cartilage. Furthermore, nine volunteers (six healthy subjects without knee pain history and three patients with known knee injury, between 29 and 58 years old) were scanned using gradient-echo acquisitions on a high-field 7T MR scanner. Susceptibility values of different tissues were quantified and diseased cartilage and meniscus were compared against that of healthy volunteers. RESULTS: Simulation and ex vivo animal cartilage experiments demonstrated that collagen fibrils exhibit an anisotropic susceptibility. A gradual change of magnetic susceptibility was observed in the articular cartilage from the superficial zone to the deep zone, forming a multilayer ultrastructure consistent with anisotropy of collagen fibrils. Meniscal tears caused a clear reduction of susceptibility contrast between the injured meniscus and surrounding cartilage illustrated by a loss of the sharp boundaries between the two. Moreover, QSM showed more dramatic contrast in the focal degenerated articular cartilage than R2* mapping. CONCLUSION: The arrangement of the collagen fibrils is significant, and likely the most dominant source of magnetic susceptibility anisotropy. Quantitative susceptibility mapping offers a means to characterize magnetic susceptibility properties of tissues in the knee joint. It is sensitive to collagen damage or degeneration and may be useful for evaluating the status of knee diseases, such as meniscal tears and cartilage disease. Magn Reson Med 78:1933-1943, 2017. © 2017 International Society for Magnetic Resonance in Medicine.

Magnetic resonance imaging as a predictor of return to play following syndesmosis (high) ankle sprains in professional football players.

BACKGROUND: Syndesmosis ankle sprains cause greater disability and longer duration of recovery than lateral ankle sprains. OBJECTIVE: To describe the severity of syndesmosis sprains using several accepted magnetic resonance imaging (MRI) criteria and to assess the interrater reliability of diagnosing syndesmosis injury using these same criteria in professional American football players. HYPOTHESIS: There is a high degree of interrater reliability of MRI findings in American football players with syndesmosis ankle sprains. These radiographic findings will correlate with time lost to injury, indicating severity of the sprain. STUDY DESIGN: Uncontrolled retrospective review. METHODS: Player demographics and time lost to play were recorded among professional football players who had sustained a syndesmosis ankle sprain and underwent standardized ankle MRI. Each image was independently read by 3 blinded musculoskeletal radiologists. RESULTS: Seventeen players met study criteria. There was almost perfect agreement among the radiologists for diagnosing injury to the syndesmotic membrane; substantial agreement for diagnosing injury to the posterior inferior tibiofibular ligament (PITFL) and in determining the proximal extent of syndesmotic edema/injury; but only fair agreement for diagnosing injury to the anterior inferior tibiofibular ligament and in determining the width of syndesmotic separation. There was a significant correlation between the width of syndesmotic separation and time lost, but no significant correlation between individual syndesmotic ligament injury or proximal extent of syndesmotic edema/injury and time lost. CONCLUSION: While ankle MRI can identify syndesmotic disruption with a high degree of interobserver agreement, no association was demonstrated between the extent of injury on MRI and the time to return to play following a high ankle sprain. CLINICAL RELEVANCE: In athletes with suspected high ankle sprains, MRI may help confirm diagnosis or suggest alternative diagnoses when the syndesmotic supporting structures are intact. However, the severity of ligamentous and syndesmotic disruption on MRI cannot help predict recovery times.

PET/CT in the assessment of previously treated skull base malignancies.

BACKGROUND: Altered anatomy, radiotherapy, hardware, and reconstructive materials distort the posttreatment ventral skull base. The diagnostic characteristics of positron emission tomography/CT (PET/CT) studies in those with suspected recurrent malignancy were assessed. METHODS: A retrospective review was undertaken of patients with head and neck cancer who had PET/CT for ventral skull base disease. RESULTS: Thirty-four PET/CTs were performed for suspected recurrent malignancy in the skull base (mean age, 59.6 +/- 10.7 years; female 38%). The group comprised mainly minor salivary (35.3%), squamous (32.3%), and neuroectodermal (23.6%) tumors. Mean clinical follow-up after PET/CT was 256 +/- 173 days. Sensitivity was 100% but specificity was 40%. Standard uptake values (SUVs) for true positives were higher than for those without disease (p = .03). CONCLUSIONS: PET/CT is a highly sensitive test for malignant disease. The mucosal lining of the reconstructed skull base is a common source for inflammatory pathologies that may lead to false-positive PET/CT. Defining SUV thresholds for malignancy may improve specificity.

Inadequate reporting of trials compromises the applicability of systematic reviews.

BACKGROUND: Uncertainty about the applicability of controlled trial findings is an increasing concern for clinicians and policy decision makers. This study aimed to determine whether information reported in studies included in systematic reviews was adequate enough to assess their applicability. METHODS: We used the databases of four recently conducted systematic reviews on the comparative efficacy and safety of second-generation antidepressants, inhaled corticosteroids, Alzheimer's drugs, and targeted immune modulators. We developed and pilot-tested a questionnaire to assess the adequacy of reporting with respect to seven previously validated criteria of study design that distinguish explanatory from pragmatic studies. For each of the 137 included studies, two reviewers independently assessed the adequacy of reporting. RESULTS: Overall, only 12 percent of the included studies provided sufficient information to reliably distinguish explanatory from pragmatic studies. The areas with the greatest lack of reporting were the setting of the study, methods of adverse event assessment, and sample size considerations to determine a minimally important difference from a patient perspective. CONCLUSIONS: Substantial shortcomings in reporting exist in aspects of study design important to determine whether a study is applicable to specific populations of interest.