Insertion Area Research Articles

Quantifying the Dimensions of Achilles Tendon Insertional Area Using Ultrasound Imaging A Validity and Reliability Study

Quantifying the Dimensions of Achilles Tendon Insertional Area Using Ultrasound Imaging A Validity and Reliability Study

The femoral posterior fan-like extension of the ACL insertion increases the failure load.

To examine the role of the posterior fan-like extension of the ACL's femoral footprint on the ACL failure load. Sixteen (n = 16) fresh frozen, mature porcine knees were used in this study and randomized into two groups (n = 8): intact femoral ACL insertion (ACL intact group) and cut posterior fan-like extension of the ACL (ACL cut group). In the ACL cut group, flexing the knees to 90°, created a folded border between the posterior fan-like extension and the midsubstance insertion of the femoral ACL footprint and the posterior fan-like extension was dissected and both areas were measured. Specimens were placed in a testing machine at 30° of flexion and subjected to anterior tibial loading (60mm/min) until ACL failure. The intact ACL group had a femoral insertion area of 182.1 ± 17.1mm2. In the ACL cut group, the midsubstance insertion area was 113.3 ± 16.6mm2, and the cut posterior fan-like extension portion area was 67.1 ± 8.3mm2. The failure load of the ACL intact group was 3599 ± 457N and was significantly higher (p < 0.001) than the failure load of the ACL cut group 392 ± 83N. Transection of the posterior fan-like extension of the ACL femoral footprint has a significant effect on the failure load of the ligament during anterior loading at full extension. Regarding clinical relevance, this study suggests the importance of the posterior fan-like extension of the ACL footprint which potentially may be retained with remnant preservation during ACL reconstruction. Femoral insertion remnant preservation may allow incorporation of the fan-like structure into the graft increasing graft strength.

The early evolution of the sabre-toothed felid killing bite: the significance of the cervical morphology of Machairodus aphanistus (Carnivora: Felidae: Machairodontinae)

Abstract The study of cervical anatomy in the Miocene machairodontine felid Machairodus aphanistus reveals the early stages of evolution of the sabre-toothed adaptations in the homotherin lineage. The cervical vertebrae of M. aphanistus show a surprising mosaic of features, combining a more primitive atlas than its derived relative Homotherium, with a set of elongated, caudal cervical vertebrae that display well-developed transverse processes with complex and strong muscle insertion areas. In spite of its primitive morphology, the atlas of M. aphanistus does show a slight caudal projection of the atlas wings, indicating an emphasis on vertical motions of the cranial portion of the neck and skull. The rest of the cervical vertebrae of M. aphanistus show clear adaptations for strength, flexibility and precise control of neck motions compatible with the canine shear-bite model and comparable to those of Homotherium. Such a powerful and flexible neck could provide additional stability to partly compensate for the risk of canine breakage created by the less specialized adaptations of the skull and cranial cervical vertebrae for the machairodontine bite.

Safe trajectory for an occipital condyle screw: A computer simulation study.

The purpose of this study was to evaluate the feasibility of posterior occipital condyle screw (OCS) placement analysis of the safe trajectory area for screw insertion. Computed tomographic angiography scans of patients (46 males and 27 females) with normal occipitocervical structures were obtained consecutively. Vertebral artery (VA)-occiput distance <4.0 mm was defined as "unfeasible" for OCS fixation, and occipital-atlas angulation was measured to assess the feasibility of screw placement. Next, the placement of 3.5 mm diameter OCS was simulated, the probability of breach of structures surrounding occipital condyles was calculated, and placement parameters were analyzed. OCS placement was feasible in 91.1% (133/146) of occipital condyles, and the feasible probability also presented a significant sex-related difference: The probability was higher for males than for females (95.7% vs. 83.3%, p < 0.05). The incidence of anatomical structures injured under screw placement limitation was 18.8% (VA), 81.2% (hypoglossal canal), 59.4% (occipital-atlas joint), and 40.6% (occiput bone surface). There were no significant differences between the left and right condyles in relation to the measured parameters (p > 0.05). The screw range of motion was significantly smaller in females than in males (p < 0.05). The feasibility of OCS placement and OCS range of motion were significantly greater in the kyphosis group (>5°) than in the other two groups (p < 0.05). OCS placement is a feasible technique for occipital-cervical fusion. The male group and occipitocervical region kyphosis group had a wider available space for OCS placement. Tangent angulation may be useful for the accurate and safe placement of an OCS.

Thermostable Lichenase from Clostridium thermocellum as a Host Protein in the Domain Insertion Approach.

Clostridium thermocellum lichenase (endo-β-1,3;1,4-glucan-D-glycosyl hydrolase, EC 3.2.1.73 (P29716)) has been tested for the insertion of two model fluorescent proteins (EGFP and TagRFP) into two regions of this enzyme. Functional folding of the resulting proteins was confirmed by retention of lichenase activity and EGFP and TagRFP fluorescence. These results convincingly demonstrate that (i) the two experimentally selected lichenase loop regions may serve as the areas for domain insertion without disturbing enzyme folding in vivo; (ii) lichenase permits not only single but also tandem insertions of large protein domains. High specific activity, outstanding thermostability, and efficient in vitro refolding of thermostable lichenase make it an attractive new host protein for the insertional fusion of domains in the engineering of multifunctional proteins.

Novel strategy of ovarian cancer implantation: Pre-invasive growth of fibrin-anchored cells with neovascularization.

Although direct adhesion of cancer cells to the mesothelial cell layer is considered to be a key step for peritoneal invasion of ovarian cancer cell masses (OCM), we recently identified a different strategy for the peritoneal invasion of OCM. In 6 out of 20 cases of ovarian carcinoma, extraperitoneal growth of the OCM was observed along with the neovascularization of feeding vessels, which connect the intraperitoneal host stroma and extraperitoneal lesions through the intact mesothelial cell layer. As an early step, the OCMs anchor in the extraperitoneal fibrin networks and then induce the migration of CD34‐positive and vascular endothelial growth factor A (VEGF‐A)‐positive endothelial cells, constructing extraperitoneal vascular networks around the OCM. During the extraperitoneal growth of OCM, podoplanin‐positive and α smooth muscle actin (αSMA)‐positive cancer‐associated fibroblasts (CAF) appears. In more advanced lesions, the boundary line of mesothelial cells disappears around the insertion areas of feeding vessels and then extraperitoneal and intraperitoneal stroma are integrated, enabling the OCM to invade the host stroma, being associated with CAF. In addition, tissue factors (TF) are strongly detected around these peritoneal implantation sites and their levels in ascites were higher than that in blood. These findings demonstrate the presence of neovascularization around fibrin net‐anchored OCMs on the outer side of the intact peritoneal surface, suggesting a novel strategy for peritoneal invasion of ovarian cancer and TF‐targeted intraperitoneal anti‐cancer treatment. We observed and propose a novel strategy for peritoneal implantation of ovarian cancer. The strategy includes the preinvasive growth of fibrin‐anchored cancer cells along with neovascularization on the outer side of the intact peritoneal surface.

Throwing Activities Among Neolithic Populations from the Meuse River Basin (Belgium, 4500–2500 BC) with a Focus on Adolescents

ABSTRACTThe anterior band of the medial collateral ligament (MCL) is an important stabilizer for valgus stress at the elbow. When practised intensively and repetitively, activities using overhead throwing motions can injure this ligament and its insertion. If these activities occur when the epiphyses are not yet fully fused, traction forces can result in bony detachments in the area of the MCL insertion. This study was based on commingled graves found in 16 Middle and Late Neolithic caves from Belgium. We recorded the presence of MCL lesions on 196 humeri and studied the relation between lesions, siding, and robusticity. 5.1% of the humeri displayed MCL lesions, which affected only the right robust humeri. Our results suggest a social division in throwing activities in Belgium during the Neolithic. They also suggest that throwing practice started from a young age, which invites us to re-examine the role of teenagers in prehistoric societies.

Comparación del grosor óseo palatino bilateral para inserción de miniimplantes

Objetivo: comparar el grosor óseo palatino bilateral e identificar zonas seguras para inserción de miniimplantes. Métodos: se llevó a cabo un estudio transversal que incluyó 100 tomografías de haz cónico (CBCT) pretratamiento de pacientes que asistieron a la Especialidad de Ortodoncia en la Universidad Autónoma de Nayarit (UAN). Las imágenes fueron orientadas utilizando el mismo protocolo. En el corte sagital, las mediciones se realizaron de los 0 a los 24mm, con intervalos de 3mm entre cada una, con la primera medición en el borde posterior del foramen incisivo. Las mediciones del grosor palatino se realizaron en el corte coronal a los 2, 4, 6 y 8mm de la sutura media palatina hacia ambos lados. Resultados: se encontró mayor grosor en la zona anterior en las medidas sagitales de 0 mm y 3 mm, a diferencia del resto del paladar. Se hallaron diferencias estadísticamente significativas al comparar los valores tanto sagitales como transversales. Con la prueba Post Hoc de Tukey no se encontraron diferencias estadísticamente significativas al comparar el lado derecho con el izquierdo en cada una de las medidas transversales. Conclusiones: no se encontraron diferencias significativas entre los dos lados, se determinó como zona segura la región anterior del paladar de 0mm a 6mm y es primordial la CBCT en todos los pacientes con indicación de miniimplantes en paladar.

Ectopic tendons of the pectoralis minor muscle as cause for shoulder pain and motion inhibition-Explaining clinically important variabilities through phylogenesis.

OJECTIVEClinical consequences of ectopic tendons of the pectoralis minor muscle (PMM) for shoulder pain and range-of-motion limitation have been demonstrated. For better understanding the existence of such ectopic tendons, a phylogenetic hypothesis is proposed.METHODSForty-five shoulders of anatomical specimens were dissected and examined. Insertions areas of PMM were measured and occurring aberrant tendons were identified. Their relationship with the coracohumeral ligament (CHL) described and samples of the ligament were collected and histologically stained.RESULTSThe prevalence of PMM variations was 37.84%. Shoulders with variations showed a statistically significant smaller coracopectoral distance (p<0.001) and larger insertion areas (p<0.003) than shoulders without. A strong negative correlation between these two variables (p<0.001, r = -0.620) was shown.CONCLUSIONSThe presented results prompted the conclusion that the CHL may be in fact the remnant of the pectoralis minor tendon (PMT), which migrated from the humerus to the coracoid process through the process of phylogenetic evolution. Variations of PMTs are significantly more common than in previous studies. Imaging techniques appear to be insufficiently sensitive for reliably detecting ectopic tendons. Especially in patients experiencing shoulder pain and stiffness in whom the commoner pathologies have been ruled out the possibility of ectopic PMT should be kept in mind and ruled out.

Behavior under Load of A Human Shoulder: Finite Element Simulation and Analysis

Most musculoskeletal injuries occur during the work routines in different areas, due to repetitive and sustained movements, they are often located in the shoulder. For workers in the building sector, the repetitive movements and displacements occur under load and unnatural postures of the shoulder joint. For this reason, this study aims to model in 3D the biological components which form the shoulder joint for the later finite element analysis. Three cases with different loads have been considered for this study. Due to a linear and isotropic joint approach it has been possible to evaluate the tensions in the main components of the shoulders: muscles, tendons and ligaments. The methodology used allowed obtaining an improved mesh of the shoulder joint to analyse real situations with finite element method analysis with applications in the field of sports medicine, work, etc. Furthermore, the simplification adopted for modelling the joint muscles, as 1D elements in the finite element model has made it possible to establish different positions of human joint without mesh again each of the studied positions. The results are consistent with the states of applied loads. In fact, the maximum stresses in bones are in the insertion areas of the ligaments. Due to the static positions of the joint under study, the muscles do not support high stresses. According to the stresses distribution, the maximum values are in the zones of tendons. From the result analysis, it is observed how the stresses distribution in the cartilage area maintains coherence with reality since the maximum stresses appear in the lower half of the cartilage. In this area in which the Humerus-scapula contact is greater, the compression tensions are greater.

Comparativo de inserción a estadías del nivel TSU en Turismo de la UTRM entre el modelo BIS y tradicional

Objective: In order to follow up on the research published in 2017 regarding the insertion of TSU Tourism: Hotel Area students in the process of the professional practicum within the productive sector, a comparative analysis of the traditional modality and the Bilingual, International and Sustainable (BIS) modality was carried out to identify the contribution from the students in the formation of human resources of the institution towards the hospitality industry. Methodology: This was a qualitative study, with a descriptive scope. The results obtained from the first investigation were considered and contrasted with the results of the insertion in professional practicums of the generation of 2017 – 2019 BIS modality. The factors considered in the comparison were: socioeconomic, company and area of insertion. Contribution: The results will be a reference for the Subsystem of Technological and Polytechnic Universities that impart the BIS modality in the Tourism program. This will allow them to identify the formation of the human resource by students in the BIS modality compared to what was seen in the traditional model, within the hospitality sector.

Acupuncture Points and Perforating Cutaneous Vessels Identified Using Infrared Thermography: A Cross-Sectional Pilot Study.

Aims To evaluate the presence of perforating cutaneous vessels (PCV) in different lower limb acupuncture points (AP) using thermography. Material and Methods An analytical cross-sectional study was performed on the two lower limbs (n=6) of volunteer subjects. In total, 144 AP and 144 control points (CP) were analysed, one for each AP. First, the AP and CP were located on each individual. Subsequently, both the real and thermographic images were created. In the real images, the location of the AP and the established CP were highlighted with boxes. FLIR Tools Plus and Physio Thermal Imaging software were used to merge the real image with the AP and the CP and to merge the thermographic image with the PCV. By superimposing both images, we were able to verify the presence of PCV among the AP and CP. Results PCV were identified in 87.5% of the 144 AP examined and in 18.1% of the respective CP. All the AP had a higher percentage of PCV compared to their respective CP, with statistically significant differences in all points, except for ST33 and ST34. The probability of finding PCV in AP was 11 times higher than the probability of not finding it. Discussion Thermography may serve as a useful tool in the assessment and treatment of patients using acupuncture. The presence of PCV in the area of the acupuncture needle insertion could partially influence the effects generated by the acupuncture technique from the vascular autonomic point of view. Conclusions There is a high proportion of PCV in the AP area located in the lower limb.

Polyurethane Transparent Dressing Protection on the Insertion Area of Peripheral Intra Venous Catheter (PIVC)

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The optimal pathway for S1 sacroiliac screwing: 3D imaging study and clinical application

Objective To determine the optimal pathway for S1 sacroiliac screwing based on the largest safe zone in Chinese population using 3D imaging models and observe its clinical application in patients with sacroiliac joint fracture or dislocation. Methods Pelvic CT scans of 54 Chinese adults were obtained to create reconstruction 3D models of the right hemi-pelvis. After the models were transparentized and rotated to the axial view of the S1 pedicle, the angle was slightly adjusted to maximize the translucent safe zone. Next, simulative insertion into the center of this zone was conducted with one virtual screw, as large as possible and tangent to the boundary. Measured were the diameter and length of the screw, the vertical distances from the entry point to the horizontal tangent line of the greater sciatic notch and to the vertical tangent line of the posterior superior iliac spine, and from the exit point to the S1 superior endplate and to the anterior cortex. The differences between males and females were analyzed. The above parameters of the optimal pathway for S1 sacroiliac screwing were used in insertion of 16 screws in the 12 patients with sacroiliac joint fracture or dislocation from January 2014 to January 2016 at Department of Orthopaedics and Traumatology, Nanfang Hospital. They were 8 males and 4 females, from 16 to 47 years of age (average, 34 years). According to the Tile classification, 6 cases belonged to Type Ⅱ and 6 ones to Type Ⅲ. The efficacy of S1 sacroiliac screwing was observed. Results In all the pelvic 3D imaging models, an oval translucent area for safe screw insertion could be easily identified from the S1 pedicle axial view. The maximum diameter and length of the optimal intraosseous pathway were 13.66±2.04 mm and 77.66±4.25 mm; the vertical distances from the entry point to the horizontal tangent line of the greater sciatic notch and to the vertical tangent line of the posterior superior iliac spine were 32.77±4.55 mm and 49.57±5.24 mm; the vertical distances from the exit point to the S1 superior endplate and to the anterior cortex were 9.30±1.54 mm and 15.85±2.12 mm. The differences were of statistical significance between males and females regarding the maximum diameter, the distance from the entry point to the vertical axis, and the distance from the exit point to the anterior cortex (P<0.05). All the 16 screws were safely implanted in the 12 patients. Conclusion The optimal screw pathway can be easily identified and its parameters can be measured in pelvic 3D imaging models using computer virtual technology. The clinical application has proved that the parameters can serve as a theoretical basis for safe placement of S1 sacroiliac screws. Key words: Sacroiliac joint; Bone nails; Fracture fixation, internal; Computer virtual technology; Anatomy

The correlation between the femoral anterior cruciate ligament footprint area and the morphology of the distal femur: three-dimensional CT evaluation in cadaveric knees.

"Anatomical" anterior cruciate ligament (ACL) reconstruction is defined as the functional restoration of the ACL to its native dimensions. It is essential to obtain more accurate predictors of ACL size before surgery. The purpose of this study was to investigate the correlation between the native femoral ACL footprint size and the morphology of the distal femur using three-dimensional CT (3D-CT). Thirty non-paired Japanese human cadaver knees were used. All soft tissues around the knee were resected except the ACL. For the evaluation of femoral condyle morphology, trans-epicondylar length (TEL), notch outlet length, axial notch area, and notch width index were measured using 3D-CT. The ACL was cut in the middle, and the femoral bone was cut at the most proximal point of the femoral notch. The ACL was carefully dissected, and the boundaries of the ACL insertion site were outlined on the femoral side. An accurate lateral view of the femoral condyle was photographed with a digital camera. The size of the femoral ACL footprint, length of Blumensaat's line, and the height and area of the lateral wall of the femoral intercondylar notch were measured with ImageJ software. Notch height, lateral notch area, and TEL were significantly correlated with the femoral ACL footprint area. Both axial notch area and notch outlet length were significantly correlated with the femoral mid-substance insertion area. Morphological evaluation using 3D-CT preoperatively may be useful in predicting the femoral ACL footprint size.

Complex abnormality combinations between the scleritome and the sclerites of Chiton articulatus (Mollusca: Polyplacophora): New findings for the teratological classification

Teratological diagnosis in polyplacophorans has mostly been based on primary structure (Chiton scleritome) with four types (hypermerism, hypomerism, coalescence and splitting), including some deformities in plates; however, diagnoses are hardly detailed for each sclerite. As part of a monthly research campaign conducted by a year investigating Chiton articulatus, we found several cases with a complex combination of abnormalities (chiton scleritome + sclerites) that complement the previous classification. Identification and diagnosis of abnormalities were assigned in terms of sclerite number, number of slits per side in the insertion area of intermediate sclerites and the merging grade between sclerites. Slit and slit-ray numbers were baseline to identify combination of abnormalities; the slit formula of Chiton articulatus is 13–18[I]/1[II-VII]/16–22[VIII]. We found four abnormality cases with combinations among them: a) perfect hypomerism, b) heterogeneous coalescence, c) homogeneous coalescence, d) imperfect hypermerism. Heterogeneous coalescence was most common abnormality, with a different merging degree between sclerites and with specimens showing combinations of abnormal states such as: normality/coalescence, coalescence/hypomerism, coalescence/hypermerism and normality/hypermerism; so these complex abnormalities can generates asymmetry between the right and left side of a chiton. We postulate that coalescence is an intermediate step toward perfect hypomerism or perfect hypermerism. The width/length ratio suggests that an abnormal chiton increases its width to compensate and retain a normal body appearance despite different degrees of abnormal development.

The Impact of Decreased Scapulothoracic Upward Rotation on Subacromial Proximities.

Decreased scapulothoracic upward rotation has been theorized to increase an individual's risk for rotator cuff compression by reducing the clearance for the tendons in the subacromial space (ie, subacromial proximities). However, the impact of decreased scapulothoracic upward rotation on subacromial proximities has not been tested during dynamic in vivo shoulder motion. To determine the impact of decreased scapulothoracic upward rotation on subacromial proximities. Shoulder kinematics were quantified in 40 participants, classified as having high or low scapulothoracic upward rotation, during scapular plane abduction using single-plane fluoroscopy and 2-D/3-D shape-matching. Subacromial proximities were calculated as (1) the normalized minimum distance between the coracoacromial arch and humeral rotator cuff insertion, and (2) the surface area of the humeral rotator cuff insertion in immediate proximity to the coracoacromial arch. The effect of decreased scapulothoracic upward rotation on subacromial proximities was assessed using 2-factor mixed-model analyses of variance. The prevalence of contact between the coracoacromial arch and rotator cuff was also quantified. Subacromial distances were generally smallest below 70° of humerothoracic elevation. With the arm at the side, the normalized minimum distance for participants in the low scapulothoracic upward rotation group was 34.8% smaller compared to those in the high upward rotation group (P = .049). Contact between the coracoacromial arch and rotator cuff tendon occurred in 45% of participants. Decreased scapulothoracic upward rotation shifts the range of risk for subacromial rotator cuff compression to lower angles. However, the low prevalence of contact suggests that subacromial rotator cuff compression may be less common than traditionally presumed. J Orthop Sports Phys Ther 2019;49(3):180-191. Epub 18 Jan 2019. doi:10.2519/jospt.2019.8590.

Вариабельность по экспрессии GFP-гена в моноклональных клеточных линиях Arabidopsis thaliana

A set of transgenic Arabidopsis thaliana monoclonal cell lines has been created by selecting individual cells (cell aggregates) with random GFP gene integration events after the Agrobacterium-mediated transformation. The yield of the recombinant GFP ranged from 0.07 to 2.37% of the total soluble protein. Three lines with the highest, about 2% of the total soluble protein, accumulation of the target GFP protein were isolated. Areas of T-DNA insertions into the plant genome for 12 monoclonal cell lines were determined. The variation in this characteristic among 21 examined cell lines can serve as a reference for A. thaliana CRISPR/Cas9 genome editing aimed at the increase in the yield of recombinant proteins in plant expression systems. The lines with the highest level of the recombinant protein accumulation are of interest for the further identification and detailed characteristics of the sites for the transgene integration. These sites can be used as targets for the gene integration during the creation of lines for the production of recombinant proteins. Arabidopsis thaliana, cell suspension culture, Agrobacterium-mediated transformation, gene expression, green fluorescent protein. The work was performed under project no. 17-14-01099 of the Russian Science Foundation.

Anatomical variations of the equine popliteal tendon.

The function of the popliteal muscle and tendon in horses remains undescribed. In humans, it is considered a stabilizer of the posterior-lateral region of the knee; its function is closely related to that of the lateral collateral ligament (LCL) and meniscus. The popliteal tendon (PopT) constitutes the main proximal attachment of the popliteus muscle to the femur, and in humans, insertional variations have been described. Knowledge of anatomical variations is needed for the correct interpretation of diagnostic images and arthroscopic findings. To elucidate further the anatomy of the equine PopT, both hind limbs of 30 horses were dissected. Similar to humans, the equine PopT has 3 variants (types I, II, and III) depending on the number of components forming the tendon. Additionally, the area of insertion varies; the location can be either cranial, underneath, or caudal to the proximal insertion of the LCL. Furthermore, the PopT has a constant attachment to the lateral meniscus. The results of the present study are useful for clinicians working with equine orthopedics, as the tendon and insertional variants could affect the interpretation of diagnostic images and arthroscopic examinations.

Differences in The Number of Germs in The Insertion Area of Central Venous Catheter (CVC) Done by Polyurethane Transparent and Plaster Gauze Dressing

A central venous catheter is a catheter that is placed directly on a large vein in the body and its tip lies in one of the central veins that is often used on critical care patients. Colonization of bacteria (germ) around the insertion area of the CVC is an area that is very likely to cause infection even though it has been closed by dressing. The factor that should always be considered is that the state of moisture retention occurs beneath the dressing. Moisture will cause an increase in colonization of the insertion area and increase the risk of catheter-related infection. As is known the humidity level of Indonesia with other countries is higher and the results of positive swabs in the insertion area are associated with Percutaneous Central Venous Catheter (PCVC) colonization and Catheter-related Sepsis (CRS). Transparent polyurethane and plaster gauze are two types of dressings that are different and often used. The transparent polyurethane is widely used in invasive procedures, there are still many medical staff who use plaster gauze dressings. The purpose of this study is to determine the difference in the number of germs in the CVC insertion area that are dressed using transparent polyurethane and plaster gauze. The design of this study is a quasi-experimental pretest-posttest control group with positive sampling. The number of samples is 12 for the intervention group and 11 for the control group. The intervention group performed transparent polyurethane dressings and a control group with plaster gauze. Calculation in the number of germs is with the cup count method. Wilcoxon and Mann-Whitney tests are for te data analysis. Based on the results of the study, it can be concluded that there is no difference in the number of CVC insertion germs between the use of dressings transparent polyurethane and plaster gauze so that both types of dressings can be used for CVC dressings in critical patient care settings.