SUMMARY Objective To summarize literature on the concurrent and predictive validity of MRI-based measures of osteoarthritis (OA) structural change. Methods An online literature search was conducted of the OVID, EMBASE, CINAHL, PsychInfo and Cochrane databases of articles published up to the time of the search, April 2009. 1338 abstracts obtained with this search were preliminarily screened for relevance by two reviewers. Of these, 243 were selected for data extraction for this analysis on validity as well as separate reviews on discriminate validity and diagnostic performance. Of these 142 manuscripts included data pertinent to concurrent validity and 61 manuscripts for the predictive validity review. For this analysis we extracted data on criterion (concurrent and predictive) validity from both longitudinal and cross-sectional studies for all synovial joint tissues as it relates to MRI measurement in OA. Results Concurrent validity of MRI in OA has been examined compared to symptoms, radiography, histology/pathology, arthroscopy, CT, and alignment. The relation of bone marrow lesions, synovitis and effusion to pain was moderate to strong. There was a weak or no relation of cartilage morphology or meniscal tears to pain. The relation of cartilage morphology to radiographic OA and radiographic joint space was inconsistent. There was a higher frequency of meniscal tears, synovitis and other features in persons with radiographic OA. The relation of cartilage to other constructs including histology and arthroscopy was stronger. Predictive validity of MRI in OA has been examined for ability to predict total knee replacement (TKR), change in symptoms, radiographic progression as well as MRI progression. Quantitative cartilage volume change and presence of cartilage defects or bone marrow lesions are potential predictors of TKR. Conclusion MRI has inherent strengths and unique advantages in its ability to visualize multiple individual tissue pathologies relating to pain and also predict clinical outcome. The complex disease of OA which involves an array of tissue abnormalities is best imaged using this imaging tool.

SUMMARY Objective To summarize literature on the responsiveness and reliability of MRI-based measures of knee osteoarthritis (OA) structural change. Methods A literature search was conducted using articles published up to the time of the search, April 2009. 1338 abstracts obtained with this search were preliminarily screened for relevance and of these, 243 were selected for data extraction. For this analysis we extracted data on reliability and responsiveness for every reported synovial joint tissue as it relates to MRI measurement in knee OA. Reliability was defined by inter- and intra-reader intra-class correlation (ICC), or coefficient of variation, or kappa statistics. Responsiveness was defined as standardized response mean (SRM) - ratio of mean of change over time divided by standard deviation of change. Random-effects models were used to pool data from multiple studies. Results The reliability analysis included data from 84 manuscripts. The inter-reader and intra-reader ICC were excellent (range 0.8–0.94) and the inter-reader and intra-reader kappa values for quantitative and semi-quantitative measures were all moderate to excellent (range 0.52–0.88). The lowest value (kappa = 0.52) corresponded to semi-quantitative synovial scoring intra-reader reliability and the highest value (ICC = 0.94) for semi-quantitative cartilage morphology. The responsiveness analysis included data from 42 manuscripts. The pooled SRM for quantitative measures of cartilage morphometry for the medial tibiofemoral joint was −0.86 (95% confidence intervals (CI) −1.26 to −0.46). The pooled SRM for the semi-quantitative measurement of cartilage morphology for the medial tibiofemoral joint was 0.55 (95% CI 0.47–0.64). For the quantitative analysis, SRMs are negative because the quantitative value, indicating a loss of cartilage, goes down. For the semi-quantitative analysis, SRMs indicating a loss in cartilage are positive (increase in score). Conclusion MRI has evolved substantially over the last decade and its strengths include the ability to visualize individual tissue pathologies, which can be measured reliably and with good responsiveness using both quantitative and semi-quantitative techniques.

Objective Osteoarthritis (OA) is currently diagnosed using clinical and radiographic findings. In recent years MRI use in osteoarthritis has increasingly been studied. This study was conducted to determine the diagnostic utility of MRI in OA through a meta-analysis of published studies. Methods A systematic literature search was undertaken to include studies that used MRI to evaluate or detect osteoarthritis. MRI was compared to various reference standards: histology, arthroscopy, radiography, CT, clinical evaluation, and direct visual inspection. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and receiver operating characteristic (ROC) area under the curve were calculated. Random effects models were used to pool results. Results Of 20 relevant studies identified from the literature, 16 reported complete data and were included in the meta-analysis, with a total of 1220 patients (1071 with OA and 149 without). Overall sensitivity from pooling data of all the included studies was 61% (95% confidence interval [CI] 53 to 68), specificity was 82% (95% CI 77 to 87), PPV was 85% (95% CI 80 to 88), and NPV was 57% (95% CI 43 to 70). The ROC showed an area under the curve of 0.804. There was significant heterogeneity in the above parameters (I2 >83%). With histology as the reference standard, sensitivity increased to 74% and specificity decreased to 76% compared with all reference standards combined. When arthroscopy was used as the reference standard, sensitivity increased to 69% and specificity to 93% compared with all reference standards combined. Conclusion MRI can detect OA with an overall high specificity and moderate sensitivity when compared with various reference standards, thus lending more utility to ruling out OA than ruling it in. The sensitivity of MRI is below the current clinical diagnostic standards. At this time standard clinical algorithm for OA diagnosis, aided by radiographs appears to be the most effective method for diagnosing OA.

Arteriovenous hemodialysis fistulas (AVFs) serve as a lifeline for many individuals with end-stage renal failure. A common cause of AVF failure is cephalic arch stenosis. Its high prevalence compounded with its resistance to treatment makes cephalic arch stenosis important to understand. Proposed etiologies include altered flow in a fistulized cephalic vein, external compression by fascia, the unique morphology of the cephalic arch, large number of valves in the cephalic outflow tract and biochemical changes that accompany renal failure. Management options are also in debate and include angioplasty, cutting balloon angioplasty, bare metal stents, stent grafts and surgical techniques including flow reduction with minimally invasive banding as well as more invasive venovenostomy with transposition surgeries for refractory cases. In this review, the evidence for the clinical relevance of cephalic arch stenosis, its etiology and management are summarized.

Injuries to the distal biceps occur at the tendinous insertion at the radial tuberosity. Distal biceps injuries range from tendinosis to partial tears to non-retracted and retracted complete tears. Acute and chronic complete tears result from a tendinous avulsion at the radial tuberosity. Acute tears result from a strong force exerted on an eccentric biceps contraction, leading to tendon injury.