Citations

Purpose The purpose of this in vitro biomechanical study was to assess the effects of the remplissage procedure for small‐ and large‐sized Hill‐Sachs lesions (HSLs) on shoulder range of motion (ROM) with a special interest in the apprehension position. Methods HSLs of 50% and 100% of the glenoid width were simulated in 7 cadaveric shoulders as small and large lesions, respectively, and the postoperative condition was reproduced by placing suture anchors on the articular surface and tying down the infraspinatus at the medial edge of the would‐be lesion site. ROMs were measured in abduction, internal rotation, and external rotation with the humerus in the adducted and abducted position. In addition, the ROM was measured in the anterior apprehension position, in which 2 torques of external rotation and extension were applied simultaneously, and external rotation and horizontal extension ROMs were measured with the humerus in different abduction angles (20°, 40°, and 60°). Results For standard ROMs, the procedure for the 50% HSL maintained complete ROMs, whereas the procedure for the 100% HSL significantly decreased external rotation ROM with the humerus in both the adducted and abducted positions, as well as abduction ROM. In the apprehension position, remplissage for the 50% HSL decreased extension ROM with the humerus abducted to 40° and 60°. Remplissage for the 100% HSL significantly decreased both external and extension ROMs regardless of the humeral abduction angle. Conclusions In the cadaveric model with an intact humeral head and the simulated postoperative condition, the remplissage procedure for a large HSL caused significant restrictions in ROM of abduction in the scapular plane and external rotation with the humerus in both adduction and abduction. It also caused significant restrictions in both external rotation and extension ROMs in the apprehension position. Clinical Relevance The indication for the remplissage procedure for the larger HSL should be considered carefully, especially for the competitive throwing athlete who needs exceptional external rotation ROM for optimal overhead throwing performance.

The second most abundant cation in seawater (SW), Mg2+, is present at concentrations of ∼53 mM. Marine teleosts maintain plasma Mg2+concentration at 1–2 mM by excreting Mg2+into the urine. Urine Mg2+concentrations of SW teleosts exceed 70 mM, most of which is secreted by the renal tubular epithelial cells. However, molecular mechanisms of the Mg2+secretion have yet to be clarified. To identify transporters involved in Mg2+secretion, we analyzed the expression of fish homologs of the Slc41 Mg2+transporter family in various tissues of SW pufferfish torafugu ( Takifugu rubripes) and its closely related euryhaline species mefugu ( Takifugu obscurus). Takifugu genome contained five members of Slc41 genes, and only Slc41a1 was highly expressed in the kidney. Renal expression of Slc41a1 was markedly elevated when mefugu were transferred from fresh water (FW) to SW. In situ hybridization analysis and immunohistochemistry at the light and electron microscopic levels revealed that Slc41a1 is localized to vacuoles in the apical cytoplasm of the proximal tubules. These results suggest that pufferfish Slc41a1 is a Mg2+transporter involved in renal tubular transepithelial Mg2+secretion by mediating Mg2+transport from the cytosol to the vacuolar lumen, and support the hypothesis that Mg2+secretion is mediated by exocytosis of Mg2+-rich vacuoles to the lumen.

SummaryObjectivesIn pediatric patients vascular access is often more difficult than in adults because of the smaller size of the vessels and the inability of the patient to cooperate without deep sedation or general anesthesia. Therefore Ultrasound has already become an invaluable tool for vascular access, but the full potential of ultrasound has yet to be fully realized. Improvements in image quality and a better understanding of optimal insertion techniques continue to help clinicians safely and efficiently place catheters with fewer complications.Methods and TechniqueThe probes used for the vascular access are mainly linear and convex type. Higher‐ frequency ultrasound provides a vivid image; however, the signals are remarkably attenuated. Therefore, the choice of the probe with appropriate frequency is essential. As blood vessels are relatively easily identified with ultrasound, ultrasound‐guided vascular access does not require as sharp images as ultrasound‐guided nerve block. For pediatric vascular access, the linear probe with 5–15 MHz, 2–5 cm depth is ideal and adequate for almost all cases. Ultrasound‐guided vascular access has two main approaches: ‘long‐axis’ or ‘in‐plane approach’ and ‘short‐axis’ or ‘transverse approach’. The long‐axis approach visualizes the vessel along the insertion pathway and is commonly used to monitor the entire approach of the needle into the vessel. The short‐axis approach is easier to show the positional relationship and depth of target vessels, but it is much harder to follow the needle tip within the tissues.ConclusionThe use of ‘real‐time’ ultrasound has been shown to increase first insertion success, reduce access time, have a higher overall success, and reduce arterial puncture. As the technology continues to improve the use of ultrasound will become as ubiquitous as the lines themselves.

Atrial and brain natriuretic peptides (ANP and BNP) are produced by the heart, and their plasma concentrations are increased in human chronic congestive heart failure. Although separate studies have suggested that circulating levels of the biologically active C-terminal ANP, the biologically inactive N-terminal ANP, and BNP may have diagnostic utility in the detection of left ventricular systolic dysfunction or left ventricular hypertrophy, no studies have directly assessed the relative value of these peptides prospectively. We therefore designed this study to compare the relative ability of the different natriuretic peptides to detect abnormal left ventricular systolic and diastolic function and left ventricular hypertrophy. Using a prospective study design, we investigated 94 patients referred for cardiac catheterization and 15 age-matched normal subjects. The diagnostic abilities of elevated plasma C-terminal ANP, N-terminal ANP-(1-30), and BNP concentrations to identify systolic dysfunction (ejection fraction <45%), diastolic dysfunction (time constant of left ventricular relaxation >55 milliseconds, left ventricular end-diastolic pressure >18 mm Hg), and left ventricular hypertrophy (left ventricular mass index >120 g/m 2 ) were objectively compared by receiver operating characteristic analysis. The areas under the receiver operating characteristic curve of BNP for detecting each of these abnormalities ranged from 0.715 to 0.908 and were significantly greater than those of C-terminal ANP or N-terminal ANP-(1-30). The sensitivity and specificity of an elevated plasma BNP, which we defined as greater than the mean+3 SD of the 15 age-matched normal subjects, were 0.83 and 0.77, respectively, for detecting ejection fraction less than 45%, 0.85 and 0.70 for detecting the time constant of left ventricular relaxation greater than 55 milliseconds, 0.63 and 0.76 for detecting left ventricular end-diastolic pressure greater than 18 mm Hg, and 0.81 and 0.85 for detecting left ventricular mass index greater than 120 g/m 2 . The use of BNP and one other peptide increased sensitivity (0.90 to 0.96), albeit with lower specificity (0.56 to 0.71). An elevated plasma BNP was a more powerful marker of left ventricular systolic dysfunction, left ventricular diastolic dysfunction, and left ventricular hypertrophy than C-terminal ANP or N-terminal ANP-(1-30) in this population of patients with suspected cardiac disease. Measurement of BNP alone or in combination with C-terminal ANP or N-terminal ANP-(1-30) has potential utility for the detection of altered left ventricular structure and function in a patient population at risk for cardiovascular disease.