Relationship Between Submental Superficial Layer Hardness and Tongue Pressure Determined Using a Tissue Durometer.

Aging affects the tongue and suprahyoid muscles, causing dysphagia and undernutrition. We hypothesized that tongue function would affect submental superficial layer hardness. Tongue movements during water retention between the tongue and palate are the same as those required during bolus formation, involving internal and external tongue muscle movement. In 28 healthy adults (14 males, 14 females, average age 28.7 ± 2.9 years), we measured the submental superficial layer characteristics (frequency [tension], stiffness, decrement [inverse of resilience], relaxation, and creep [deformation over time]) using a simple tissue durometer (MyotonPRO®), and examined their relationship with maximum voluntary tongue pressure. The tissue durometer sensor was placed in the submental region, where there is no intervening bone. Measurements were performed at rest and while retaining 5 mL water. Tongue pressure was measured using a tongue pressure-measuring device. The submental superficial layer hardness differed significantly between rest and during water retention. During water retention, frequency and stiffness were high, while decrement, relaxation, and creep were low. When pressure is applied to the palate, such as during water retention the inner tongue muscle, which changes the tongue's shape, and the outer tongue muscle, which moves the tongue laterally, are active. However, the change in the hardness of the submental superficial layer during water retention may be related to the suprahyoid muscles that are present in this layer. The results of this study suggested that the hardness of the submental superficial layer changed during water retention, and that tongue movement could be measured from outside the mouth.

Apply ultra-thin lobulated anterolateral thigh perforator flap in repairing of large soft tissue defect in foot: a report of 8 cases / 中华显微外科杂志

Objective:Exploring the clinical efficacy of using ultra-thin lobulated anterolateral thigh perforator flap(ALTPF) with retrograde separation of perforating vessels from the superficial and deep junction layer of the superficial fascia to repair large soft tissue defects in the foot.Methods:From August 2021 to November 2022, 8 patients (5 males and 3 females) were admitted to the Second Department of Hand and Foot Surgery, the Affiliated Central Hospital of Dalian University of Technology. The patients were 28 to 52 years old in age. The soft tissue defects were located in dorsal and plantar foot. At the plantar foot, the wound involved the weight-bearing area with explosion of bone, tendon or internal fixtures. The area of soft tissue defects was 6.0 cm × 5.0 cm - 16.0 cm × 8.0 cm, and the sizes of ALTPF were 8.0 cm ×5.5 cm - 18.0 cm × 8.5 cm. Preoperative high frequency CUD combined with CTA angiography were employed to locate the 2 flap perforator vessels. By keeping the perforator vessels at center and according to the soft tissue defect area and the wound shape, an ALTPF with a proper size and shape was designed in anterolateral thigh. The perforator were separated in the boundary layer between superficial and deep fascia, where it helped to obviously thin the flap. After the flap was harvested, it was further lobulated between the 2 perforators into 2 lobes after having confirmed the effective blood supply. Finally the lobulated ALTPF was transferred to covered the defect in foot. Cautions should be taken to ensure that the flap covered the weight-bearing area of foot. All the donor sites were directly sutured. Postoperative follow-up was conducted to observe the survival of flaps and the functional recovery of the reconstructed site, also to evaluate the clinical effect. Postoperative follow-up included outpatient visits and reviews over WeChat or telephone. Recovery of the ankle motor function was evaluated according to the American Orthopedic Foot and Ankle Societ (AOFAS) ankle-hind foot score scale.Results:All 8 ALTPF survived. Over 6 to 18 months (10.8 months in average) of follow-up, the transferred flaps had good blood supply, soft in texture, with good elasticity and thin in appearance. Appearance and function of donor sites recovered well, except 1 patient who had mild scar hyperplasia. The plantar flap had good abrasion resistance. No flap damage, bleeding or granulation tissue hyperplasia occurred when walking. The mean score of AOFAS ankle-hind foot score achieved 95.6.Conclusion:The application of ultra-thin lobulated ALTPF with retrograde separation of perforating vessels from the superficial fascia at the junction layer for repairing large soft tissue defects in the foot has good clinical efficacy.

Influence of material heterogeneity on the mechanical response of articulated cartilages in a knee joint.

Structurally, the articular cartilages are heterogeneous owing to nonuniform distribution and orientation of its constituents. The oversimplification of this soft tissue as a homogeneous material is generally considered in the simulation domain to estimate contact pressure along with other physical responses. Hence, there is a need for investigating knee cartilages for their actual response to external stimuli. In this article, impact of material and geometrical heterogeneity of the cartilage is resolved using well known material models. The findings are compared with conventional homogeneous models. The results indicate vital differences in contact pressure distribution and tissue deformation. Further, this study paves way for standardizing material models to extract maximum information possible for investigating knee mechanics with variable geometry and case specific parameters.

Postoperative clinical outcomes and radiological healing according to deep and superficial layer detachment in first facet involving subscapularis tendon tear.

BACKGROUND: Subscapularis tendon insertion at the first facet has separate layers (deep and superficial). The purpose of this study is to evaluate postoperative clinical outcomes and radiological healing according to each layer of detachment in the first facet involving subscapularis tendon tear. METHODS: Eighty-three patients who underwent arthroscopic repair due to First facet involving the scapularis tendon tear accompanying small to medium sized posterosuperior cuff tear were classified into three groups (group A: deep layer partial detachment, group B: deep layer complete detachment, but no superficial layer detachment, and group C: deep layer and superficial layer complete detachment). Subscapularis tendon healing was evaluated using computed tomography arthrogram and clinical result was evaluated using American Shoulder and Elbow Surgeons (ASES) shoulder score, Constant score and University of California Los Angeles (UCLA) shoulder score. RESULTS: Retear rate of the subscapularis tendon was 2.2%, 18.2%, and 33.3% in group A, group B, and group C, respectively. These rates showed statistically significant difference among the three groups, which were classified by deep and superficial layer detachment in the first facet (p=0.003). Group A showed significant difference in subscapularis tendon healing compared with group B and group C (p=0.018 and p<0.001, respectively), but there was no statistical difference between group B and group C (p=0.292). Regarding clinical outcomes, there was no significant difference among three groups in ASES and UCLA score at final follow-up (p=0.070 and p=0.106, respectively). CONCLUSIONS: Complete detachment of deep layer may be related with retear occurrence regardless with detachment of superficial layer, but clinical outcome may not be related with each layer detachment in the first facet involving subscapularis tendon tear.

Multiple umbilical cord-derived MSCs administrations attenuate rat osteoarthritis progression via preserving articular cartilage superficial layer cells and inhibiting synovitis.

BACKGROUND/OBJECTIVES: Articular cartilage erosion probably plays a substantial role in osteoarthritis (OA) initiation and development. Studies demonstrated that umbilical cord-derived mesenchymal stem cells (UCMSCs) could delay chondrocytes apoptosis and ameliorate OA progression in patients, but the detailed mechanisms are largely uncharacterised. In this study, we aimed to study the effects of UCMSCs on monosodium iodoacetate (MIA)-induced rat OA model, and explore the cellular mechanism of this effect. METHODS: Intra-articular injection of 0.3 â€‹mg MIA in 50 â€‹µL saline was performed on the left knee of the 200 â€‹g weight male Sprague-Dawley rat to induce rat knee OA. A single dose of 2.5 â€‹× â€‹105 undifferentiated UCMSCs one day after MIA or three-time intra-articular injection of 2.5 â€‹× â€‹105 UCMSCs on Days 1, 7 â€‹and 14 were given, respectively. Four weeks after MIA, joints were harvested and processed for paraffin sections. Safranine-O staining, haematoxylin and eosin staining â€‹and immunohistochemistry of MMP-13, ADAMTS-5, Col-2, CD68 â€‹and CD4 were performed to observe cartilage erosion and synovium. For in vitro â€‹studies, migration ability of cartilage superficial layer cells (SFCs) by UCMSCs were accessed by transwell assay. Furthermore, catabolism change of MIA-induced SFCs by UCMSCs was performed by real-rime polymerase chain reaction of Col-X and BCL-2 genes. CCK-8 assay was performed to check proliferation ability of SFCs by UCMSCs-conditioned media. RESULT: In this study, we locally injected human UCMSCs, which is highly proliferative and noninvasively collectible, into MIA-induced rat knee OA. An important finding is on obviously ameliorated cartilage erosion and decreased OA Mankin score by repeated UCMSCs injection after MIA injection compared with single injection, both of which attenuated OA progression compared with vehicle. Interestingly, we observed significantly increased number of SFCs on the articular cartilage surface, probably related to elevated proliferation, mobilisation and inhibited catabolism marker: Col-X and BCL-2 gene expression of cultured SFCs by UCMSCs-conditioned media treatment in vitro. In addition to the change of unique SFCs, catabolism markers of ADAMTS-5 and MMP-13 were substantially upregulated in the whole cartilage layer chondrocytes as well. Strikingly, MIA-induced inflammatory cells infiltration, on both CD4+ Th cells and CD68+ macrophages, and hyperplasia of the synovium, which was alleviated by repeated UCMSCs injection. CONCLUSION: Our study demonstrated a critical role of repeated UCMSCs dosing on preserving SFCs function, cartilage structure and inhibiting synovitis during OA progression, and thus provided mechanistic proof of evidence for the use of UCMSCs on OA patients in the future. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: UCMSCs are a relatively "young" stem cell, and noninvasively collectible. In our study, we clearly demonstrated that it could effectively delay OA progression, possibly through reserving SFCs function and inhibiting synovitis. Therefore, it could be a new promising therapeutic cell source for OA after further clinical trials.

Impact of Skull Thickness on Cerebral NIRS Oximetry in Neonates: An in silico Study.

Monitoring of cerebral tissue oxygen saturation (StO2) by near-infrared spectroscopy (NIRS oximetry) has great potential to reduce the incidence of hypoxic and hyperoxic events and thus prevent long-term disabilities in preterm neonates. Since the light has to penetrate superficial layers (bone, skin and cerebrospinal fluid) before it reaches the brain, the question arises whether these layers influence cerebral StO2 measurement. We assessed this influence on the accuracy of cerebral StO2 values. For that purpose, we simulated light propagation with 'N-layered medium' software. It was found that with a superficial layer thickness of ≤6 mm, typical for term and preterm neonates, StO2 accurately reflects cerebral tissue oxygenation.

Assessment of valgus laxity after release of the medial structure in medial open-wedge high tibial osteotomy: an in vivo biomechanical study using quantitative valgus stress radiography.

BACKGROUND: To perform medial open-wedge high tibial osteotomy (OWHTO), surgeons expose the medial-proximal tibia by releasing or cutting the superficial layer of the medial collateral ligament (sMCL). Biomechanically, the sMCL provides primary restraint against valgus forces. Therefore, any release of the sMCL can cause valgus instability of the knee joint. The purpose of this study was to assess valgus laxity after release of the medial structure of the knee during OWHTO. METHODS: Between 2009 and 2015, 84 consecutive patients (93 knees) who underwent OWHTO using a locking plate were enrolled in this study. All patients underwent radiological examinations before surgery, during surgery, 1 year after surgery, and after plate removal to objectively assess valgus laxity. The medial joint space (MJS) and the joint line convergence angle (JLCA) of the knee were evaluated using quantitative valgus stress radiography. Clinical evaluation was performed 2 years after surgery. RESULTS: The mean functional knee score improved significantly, from 65.5 to 91.1 points (p < 0.0001). The mechanical axis percentage shifted to pass through a point 69.7% lateral from the medial edge of the tibial plateau. The MJS and JLCA increased significantly during OWHTO surgery (11.0 mm, 7.4 °, p < 0.0001). However, no significant differences were noted in the MJS and JLCA among preoperative, 1-year postoperative periods and after plate removal. CONCLUSION: Valgus laxity was significantly greater after release of the sMCL. However, no significant differences were noted in valgus laxity in preoperative, 1-year postoperative periods and after plate removal. Complete release of the sMCL did not cause postoperative valgus laxity after OWHTO surgery. TRIAL REGISTRATION: Trial registration number: No.012-0360.

Application of confocal, SHG and atomic force microscopy for characterizing the structure of the most superficial layer of articular cartilage.

The surface of articular cartilage plays a crucial role in attenuating and transmitting mechanical loads in synovial joints to facilitate painless locomotion. Disruption to the surface of articular cartilage causes changes to its frictional properties instigating the deterioration of the tissue. In this study, we physically peeled the most superficial layer, a transparent membrane of 20.0 ± 4.7 µm thick, from the central loading region of femoral condyles of sheep. The ultrastructure of this layer without interference from the underlying cartilage was independently investigated using confocal, second harmonic generation and atomic force microscopy. We found that the most superficial layer contains chondrocytes, densely packed collagen, coarse elastic fibres and a fine elastic network. The elastic fibres are most prevalent at the surface of the layer, where collagen and chondrocyte densities are lowest. At the interface of this most superficial layer with the underlying bulk cartilage, a dense fibrillar network exists, formed mainly by collagen fibrils and elastin microfibrils. By contrast, the interface of the underlying cartilage with the most superficial layer contains collagen fibrils, fine microfibrils and microfibrils distinctively laced on one side. The findings of this study will play an important role in understanding the mechanical function and wear resistance of articular cartilage, and in developing more promising tissue engineering techniques to treat cartilage defects and osteoarthritis. LAY DESCRIPTION: The chronic pain and dysfuction in synovial joints caused by osteoarthritis can have a debilitating impact on daily activities for sufferers. Osteoarthritis is characterised by the deterioration of the articular cartilage. Despite intensive research, the wear mechanism of articular cartilage and the progression of osteoarthritis remain unclear in the literature. Articular cartilage is a resilient tissue that provides a low friction surface to facilitate painless locomotion. The surface of articular cartilage plays a crucial role in attenuating and transmitting mechanical loads. Disruption at the surface of articular cartilage causes changes to its frictional properties, instigating the deterioration of the tissue. Despite this, the definition of the most superficial layer of articular cartilage, as well as its composition and microstructure, have endured a long history of debate, clouding our understanding of the early progression of osteoarthritis. In order to investigate the surface of articular cartilage independently from the underlying cartilage, we physically peeled a transparent membrane of 20.0 ± 4.7 µm thickness, the most superficial layer, from the central loading region of the femoral condyles of sheep. Using confocal, second harmonic generation and atomic force microscopy, we found that the most superficial layer contains cartilage cells (chondrocytes), densely packed collagen, coarse elastic fibres and a fine elastic network. The coarse elastic fibres are most prevalent at the surface of the layer where collagen and chondrocyte densities are lowest. Furthermore, we investigated the surfaces at the interface of the most superficial layer with the underlying articular cartilage. At the interface of this most superficial layer with the underlying bulk cartilage, a dense fibrillar network exists, formed mainly by collagen fibrils and elastin microfibrils. In contrast, the interface of the underlying cartilage with the most superficial layer contains collagen fibrils, fine microfibrils and microfibrils distinctively laced on one side. The findings of this study have confirmed that there is a most superficial layer that is able to be removed using a tangential force. Through the application of advanced imaging technologies, we have shown that this most superficial layer is cellular and have detailed its composition and ultrastructure. Due to the close association between the form and function of tissues, the findings of this study will play an important role in understanding the mechanical function and wear mechanism of articular cartilage. This may lead to the development of more promising tissue engineering techniques to treat cartilage defects and osteoarthritis.

Bilateral supernumerary clavicular heads of sternocleidomastoid muscle in a Korean female cadaver.

Many anatomical variants on the sternocleidomastoid muscle have been reported. In this study, supernumerary clavicular heads of sternocleidomastoid muscle in a Korean female cadaver were bilaterally displayed. The observed supernumerary heads were classified as follows: one sterno-mastoid, one cleido-occipital and one cleido-mastoid on the right side, and one sterno-mastoid-occipital, four cleido-occipitals, and one cleido-mastoid on the left side. The sterno-mastoid and sterno-mastoid-occipital and the cleido-occipital made the superficial layer of the sternocleidomastoid muscle, while others made deep layer. We discussed clinical relevance and developmental basis of these muscular variations important for clinicians and anatomists.

Superficial-Layer-Enhanced Raman Scattering (SLERS) for Depth Detection of Noncontact Molecules.

Although the strength of Raman signals can be increased by many orders of magnitude on noble metal nanoparticles, this enhancement is confined to an extremely short distance from the Raman-active surface. The key to the development of Raman spectroscopy for applications in diagnosis and detection of cancer and inflammatory diseases, and in pharmacology, relies on the capability of detecting analytes that are noninteractive with Raman-active surfaces. Here, a new Raman enhancement system is constructed, superficial-layer-enhanced Raman scattering (SLERS), by covering elongated tetrahexahedral gold nanoparticle arrays with a superficial perovskite (CH3 NH3 PbBr3 ) film. Plasmonic decay is depressed along the vertical direction away from the noble metal surface and the penetration depth is increased in the perovskite media. The vertical penetration of SLERS is verified by the spatial distribution of the analytes via Raman imaging in layer-scanning mode.

Location and thickness of delaminated rotator cuff tears: cross-sectional analysis with surgery record review.

BACKGROUND: To facilitate better treatment, we analyzed morphologic features of delamination from the viewpoint of the location of delamination and the thickness of each layer. MATERIALS AND METHODS: Of 270 shoulders that consecutively underwent arthroscopic rotator cuff repair, 210 were included. During the operation, the surgeon assessed the size of the rotator cuff tear, determined the presence and location of delamination, and compared the thickness between superficial and deep layers if delamination was present. Immediately after the operation, the surgeon wrote down the data in the record form. The authors retrospectively referred to these surgical records to investigate those items. RESULTS: Delamination was found in 111 of 210 shoulders. The overall preoperative Constant score did not significantly differ between the 2 groups. In terms of the location, 7.2% cases had delamination in the anterior part, 74.8% in the posterior part, and 18.0% in both parts (Fleiss κ = 0.9). The larger the rotator cuff tear, the more frequently the delamination was limited to the posterior part (trend P = .001). As for layer thickness comparison, 40.0% of the shoulders with small tears, 38.8% with medium tears, 66.0% with large tears, and 80.0% with massive tears had a thicker deep layer than superficial layer (Fleiss κ = 0.9). The larger the size of the rotator cuff tear, the more frequently the deep layer was thicker than the superficial layer (trend P = .001). CONCLUSIONS: The larger the rotator cuff tear, the more carefully shoulder surgeons should observe and treat the posterior and deep part of delamination.

Lubricin is Required for the Structural Integrity and Post-natal Maintenance of TMJ.

The Proteoglycan 4 (Prg4) product lubricin plays essential roles in boundary lubrication and movement in limb synovial joints, but its roles in temporomandibular joint (TMJ) are unclear. Thus, we characterized the TMJ phenotype in wild-type and Prg4(-/-) mouse littermates over age. As early as 2 weeks of age, mutant mice exhibited hyperplasia in the glenoid fossa articular cartilage, articular disc, and synovial membrane. By 1 month of age, there were fewer condylar superficial tenascin-C/Col1-positive cells and more numerous apoptotic condylar apical cells, while chondroprogenitors displayed higher mitotic activity, and Sox9-, Col2-, and ColX-expressing chondrocyte zones were significantly expanded. Mutant subchondral bone contained numerous Catepsin K-expressing osteoclasts at the chondro-osseous junction, increased invasive marrow cavities, and suboptimal subchondral bone. Mutant glenoid fossa, disc, synovial cells, and condyles displayed higher Hyaluronan synthase 2 expression. Mutant discs also lost their characteristic concave shape, exhibited ectopic chondrocyte differentiation, and occasionally adhered to condylar surfaces. A fibrinoid substance of unclear origin often covered the condylar surface. By 6 months of age, mutant condyles displayed osteoarthritic degradation with apical/mid-zone separation. In sum, lubricin exerts multiple essential direct and indirect roles to preserve TMJ structural and cellular integrity over post-natal life.