Paavo-Ilari Kuikka

Endothelial dysfunction is a systemic disorder and risk factor for atherosclerosis. Our aim was to assess whether there is a relation between peripheral endothelial function and myocardial perfusion in patients with coronary artery disease (CAD). We prospectively studied 54 patients, who had a positive result for obstructive CAD in coronary CT angiography. Myocardial perfusion (¹⁵O)H₂O positron emission tomography was imaged at rest and during adenosine-induced maximal vasodilation. Peripheral endothelial function was assessed by measuring flow-mediated dilation (FMD) with ultrasound from the left brachial artery. There was a statistically significant correlation between FMD and global hyperaemic myocardial blood flow (MBF; r = 0.308, P = 0.023). The correlation remained statistically significant when controlling for gender, height, and diastolic blood pressure at rest (r = 0.367, P = 0.008). Receiver operating character analysis, however, yielded an area under curve of only 0.559 (P = 0.492) when FMD was used to predict reduced MBF (below 2.3 mL/g/min). Patients with significantly decreased MBF (n = 14) underwent invasive coronary angiography. FMD showed an inverse correlation with the severity of the most significant stenosis (r = −0.687, P = 0.007). Peripheral endothelial function is related with hyperaemic MBF and with the severity of CAD in invasive coronary angiography. Due to insufficient sensitivity and specificity in the identification of reduced MBF, FMD is not suitable for clinical practice at the individual level. However, it works at the population level as a research tool when assessing endothelial dysfunction in patients with CAD.

The population‐based incidence and risk factors for knee injuries in young adults were assessed in Finnish male conscripts performing their compulsory military service (n = 128 584). The main outcome variables were (1) hospitalization due to knee injuries overall and (2) hospitalization due to knee disorders as categorized into specific International Classification of Diseases, tenth revision diagnoses (cruciate and collateral ligament tears, meniscal tears, traumatic chondral lesions, and patellar dislocations). Person‐time injury‐incidence rates were calculated by dividing the number of persons with a diagnosed knee injury by the total exposure time of 97 503 person‐years. The number of subjects with surgical operations and military service class changes indicative of longer term notable disability are also reported. Risk factor analyses were performed by logistic regression. The person‐based incidence of hospitalizations for knee injury was 11 cases per 1000 person‐years [95% confidence interval (CI): 10.4–11.7]. The most important risk factors were higher age (odds ratio 1.7; 95% CI: 1.3–2.2) and obesity (odds ratio 1.6; 95% CI: 1.03–2.5). Two thirds of all subjects hospitalized for knee injuries had surgery, and one third had longer term notable disability. These findings indicate that knee injuries cause a significant burden of hospitalizations, often leading to surgery and longer term disability.

Ears) with anterior knee pain had magnetic resonance imaging of the knee followed by arthroscopy. The patellar chondral lesions identified by magnetic resonance imaging were compared with the arthroscopic findings. Results: Arthroscopy confirmed the presence of chondromalacia patellae in twenty-five (45%) of the fifty-six knees, a synovial plica in twenty-five knees, a meniscal tear in four knees, and a femorotibial chondral lesion in four knees; normal anatomy was seen in six knees. No association was found between the severity of the chondromalacia patellae seen at arthroscopy and the clinical symptoms of anterior knee pain syndrome (p = 0.83). The positive predictive value for the ability of 1.0-T magnetic resonance imaging to detect chondromalacia patellae was 75% (95% confidence interval, 53% to 89%), the negative predictive value was 72% (95% confidence interval, 56% to 84%), the sensitivity was 60% (95% confidence interval, 41% to 77%), the specificity was 84% (95% confidence interval, 67% to 93%), and the diagnostic accuracy was 73% (95% confidence interval, 60% to 83%). The sensitivity was 13% (95% confidence interval, 2% to 49%) for grade-I lesions and 83% (95% confidence interval, 59% to 94%) for grade-II, III, or IV lesions. Conclusions: Chondromalacia patellae cannot be diagnosed on the basis of symptoms or with current physical examination methods. The present study demonstrated no correlation between the severity of chondromalacia patellae and the clinical symptoms of anterior knee pain syndrome. Thus, symptoms of anterior knee pain syndrome should not be used as an indication for knee arthroscopy. The sensitivity of 1.0-T magnetic resonance imaging was low for grade-I lesions but considerably higher for more severe (grade-II, III, or IV) lesions. Magnetic resonance imaging may be considered an accurate diagnostic tool for identification of more severe cases of chondromalacia patellae. Level of Evidence: Diagnostic Level I. See Instructions to Authors for a complete description of levels of evidence....

Background: No previous research has investigated the diagnostic validity of magnetic resonance imaging for acute versus chronic meniscal tears using comparable materials and methods. Hypothesis: There is no difference in the diagnostic validity of magnetic resonance imaging for acute versus chronic meniscal tears in young adults. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: A total of 628 young adult military personnel underwent magnetic resonance imaging and arthroscopy of the knee over a 6-year period. Inclusion criteria were met by 82 patients with acute knee trauma (magnetic resonance imaging within 30 days from trauma) and 40 patients with chronic knee symptoms (symptoms lasting over 6 months before magnetic resonance imaging). The original magnetic resonance imaging and arthroscopy records were reviewed twice by a musculoskeletally trained radiologist, blinded to previous magnetic resonance imaging and arthroscopy findings. Interobserver correlations and intraobserver reliability were calculated and reported. Arthroscopy served as the gold standard when calculating the diagnostic values of magnetic resonance imaging for acute and chronic meniscal tears. Results: The median age of the patients was 20 years (range, 18-25). Magnetic resonance imaging detected acute meniscal tears with sensitivity of 67%, specificity of 93%, and diagnostic accuracy of 88% and chronic meniscal tears with 64%, 91%, and 86%, respectively. There was no statistically significant difference in magnetic resonance imaging results between the 2 groups. Conclusion: The diagnostic validity of magnetic resonance imaging is similar for meniscal tears in acute knee trauma and in knee symptoms lasting over 6 months in young adults. The results also suggest that effusion or hemarthrosis do not weaken the diagnostic validity of magnetic resonance imaging. The magnetic resonance imaging sensitivity achieved in the present study was relatively poor, but the specificity was good for both acute and chronic meniscal tears. Despite negative magnetic resonance imaging findings at the acute stage of knee trauma, patient monitoring and readiness for arthroscopy should be considered if justified by the patient's symptoms.

This prospective study aimed to evaluate if chondral and meniscal lesions in symptomatic knees of osteoarthritis patients can be reliably identified using only one sagittal dual-echo MRI (Magnetic Resonance Imaging) sequence. MRI was performed on 13 patients after knee arthroscopy due to knee pain and clinically suspected osteoarthritis using a 1.5-Tesla scanner with knee coil and a sagittal dual-echo turbo spin-echo PD (Proton Density)- and T2-weighted sequence. The MRI and arthroscopic findings were then compared. Of 65 articular surfaces, 47 were damaged. For articular cartilage lesions, the overall sensitivity of MRI was 46.8%, specificity 72.2%, and diagnostic accuracy 53.9%, and for meniscal ruptures 81.2%, 66.7%, and 73.1%, respectively. The present study showed that the reliability of screening MRI of knees using only one sagittal dual-echo sequence does not suffice for diagnosis of chondral or meniscal lesions, and should therefore not replace routine knee MRI or diagnostic arthroscopy.

Purpose: The purpose of this study was to evaluate the sensitivity, specificity, and accuracy of routine 1.0‐Tesla magnetic resonance imaging (MRI) versus arthroscopy in detecting fresh traumatic chondral lesions of the knee. Methods: Over a period of 6 years, 578 consecutive military personnel underwent MRI before arthroscopy of the knee. Of these, 32 patients with arthroscopically proven fresh traumatic chondral lesions of the knee were chosen for further analysis. A supplementary condition was that arthroscopy was performed no later than 6 weeks after the onset of trauma. The original MRIs and hospital records were re‐evaluated and the chondral lesions were graded and compared with arthroscopic findings. The arthroscopic results served as the gold standard when the sensitivity, specificity, and accuracy of MRI were calculated. Results: The age of the patients ranged from 19 to 21 years (mean, 19.6 years). MRI detected cartilage defects with a sensitivity of 36% (95% confidence interval [CI], 23% to 50%), specificity of 91% (95% CI, 85% to 95%), and diagnostic accuracy of 78% (95% CI, 72% to 83%). MRI results were affected by the grade of the chondral lesions. Conclusions: This study shows that routine 1.0‐T MRI is not sensitive but is specific and somewhat accurate in detecting fresh traumatic articular cartilage lesions. The hypothesis of this study was that 1.0‐T MRI could replace diagnostic arthroscopy in the diagnosis of fresh traumatic chondral lesions. Our results fail to support this hypothesis because of the poor sensitivity obtained with MRI. Level of Evidence: Level II, development of diagnostic criteria.