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Background The type B3 glenoid is an addition to the Walch classification. A potential etiologic theory is that it is a progression of the B2. It is characterized by uniconcavity, absent paleoglenoid, medialization, retroversion, and subluxation. The purpose of this study was to describe the morphology of B3 glenoids. Methods Fifty-two patients with B3 glenoids underwent 3-dimensional analysis of computed tomography data. Glenoid measurements (retroversion, inclination, medialization) and humeral head subluxation according to the scapular and glenoid planes were determined. The measured variables were compared between male and female patients. Results The mean B3 retroversion, inclination, and medialization were 24° ± 7°, 8° ± 6° superior, and 14 ± 4 mm, respectively. The mean posterior subluxation was 80% ± 8% and 54% ± 6% according to the scapular and glenoid planes, respectively. There were no differences in B3 characteristics between sexes ( P  > .05). A significant correlation existed between glenoid retroversion and humeral head subluxation relative to the scapular plane, with every 1° increase in retroversion translating to a 1% increase in subluxation ( P  < .001). In contrast, when referencing the glenoid plane, the humeral head remained concentric to the erosion. Conclusions The B3 is uniconcave and retroverted. As glenoid retroversion increases, posterior humeral head subluxation significantly increases as referenced to the scapular plane; however, when referenced to the glenoid plane, the head remains concentric to the erosion. This appearance of “concentricity” is acquired secondary to the wear pattern, creating a uniconcave glenoid. Therefore, surgeons should be aware that the visualized concentricity is a product of the erosion pattern and thus may conceal a greater amount of subluxation potential. [ABSTRACT FROM AUTHOR]

Background: Posterior glenoid erosion is thought to be initiated by humeral head subluxation. However, it is unknown whether subluxation is entirely caused by soft-tissue instability and unbalanced muscle activity or whether osseous morphology is a contributing factor. We hypothesized that patients with posterior erosion may exhibit premorbid glenoid morphology that is inherently retroverted and inferiorly inclined compared with age-matched normal glenoids. Methods: This study examined 80 scapulae, evenly distributed between 2 groups: osteoarthritic with type B2 glenoids and age-matched normal glenoids. From 3-dimensional computed tomography reconstructions, version and inclination were measured from the anterior paleoglenoid region of the B2 glenoids, which is representative of the premorbid glenoid, and compared with measurements obtained from similar regions in the normal cohort. Results: The anterior paleoglenoid region of B2 glenoids was significantly ( P  < .001) more retroverted (−14° ± 6°) compared with similar regions in nonarthritic normal glenoids (−5° ± 5°). There were no significant differences ( P  = .166) in the glenoid inclination angle between type B2 glenoids (0° ± 6°) and nonarthritic normal glenoids (2° ± 5°). Negative values represent retroverted and inferiorly inclined glenoids. Discussion: Understanding premorbid glenoid morphologic variations may provide insight into the pathoanatomy of humeral head subluxation, osteoarthritis, and posterior glenoid erosion. The results of this study indicate that patients with type B2 osteoarthritic glenoids have significantly greater premorbid glenoid retroversion compared with nonarthritic normal glenoids, suggesting that this premorbid morphologic variation may be one contributing factor to posterior erosion. [ABSTRACT FROM AUTHOR]

Background The purpose of this study was to evaluate and to compare the size and morphologic patterns among normal and osteoarthritic (OA) humeral heads. Methods This comparative anatomic imaging study evaluated 150 humeral heads that were separated into 3 cohorts: normal, OA with symmetric glenoid erosion, and OA with asymmetric (type B2) glenoid erosion. Three-dimensional models were created of the humeral head from computed tomography data, and point coordinates were extracted for evaluation. Parameters measured were diameter (sphere fit and circle fit), chord distance (superoinferior and anteroposterior), and humeral head height. Results The sphere-fit diameter of the humeral head for the entire OA cohort (100 patients; mean diameter, 59 ± 9 mm) was significantly greater ( P < .001) than that of the normal cohort (50 patients; mean diameter, 49 ± 5 mm). Similarly, the humeral head circle-fit diameters in the superoinferior and anteroposterior planes were significantly greater ( P < .001) in the combined OA cohorts (59 ± 9 mm and 56 ± 10 mm, respectively) compared with the normal cohort (51 ± 5 mm and 47 ± 5 mm, respectively). However, there were no significant differences ( P ≥ .099) between the symmetric and asymmetric OA cohorts in sphere-fit or circle-fit diameters. The mean values of humeral head heights were not significantly different ( P = .382) between cohorts, 19 ± 2 mm, 18 ± 2 mm, and 18 ± 2 mm for the normal, symmetric, and asymmetric cohorts, respectively. Discussion Although OA humeral head morphology varies significantly from normal, it does not vary as a function of the Walch classification between symmetric and asymmetric glenoids. Understanding of the morphologic variability of the pathologic humeral head may provide insight into the pathoanatomy of osteoarthritis and the development of various erosion patterns. [ABSTRACT FROM AUTHOR]

The number of shoulder arthroplasty procedures has increased dramatically in recent years, with the primary indication being osteoarthritis (OA). Thus, morphology and subchondral bone changes associated with OA may be important factors to consider when choosing a replacement component. For surgical treatment, many implant options exist and survivability is often dependent on patient age, activity level, and progression of OA. In the placement of these replacement components, patient-specific guides now exist to improve component positioning, with the goal to improve long-term survivability by ensuring that intra-operative placement meets component design. [ABSTRACT FROM AUTHOR]

Purpose: To develop and characterize a microscale pectin-oligochitosan hydrogel microcapsule system that could be applied in such biological fields as drug delivery, cell immobilization/encapsulation, and tissue engineering. Methods: Microscale pectin-oligochitosan hydrogel microcapsules were prepared by using the vibration/electrostatic spray method. The morphology and chemistry of the hydrogel microcapsules were characterized by using scanning electron microscope (SEM) and Fourier Transform Infrared Spectroscopy (FTIR), respectively. The designed hydrogel microcapsule system was then used to study the responsiveness of the microcapsules to different simulated human body fluids as well as cell encapsulation. Results: The designed hydrogel microcapsule system exhibited a large surface area-to-volume ratio (red blood cell-shaped) and great pH/enzymatic responsiveness. In addition, this system showed the potential for controlled drug delivery and three-dimensional cell culture. Conclusions: This system showed a significant potential not only for bioactive-agent delivery, especially to the lower gastrointestinal (GI) tract, but also as a three-dimensional niche for cell culture. In particular, the hydrogel microcapsule system could be used to create artificial red-blood-cells as well as blood substitutes. [ABSTRACT FROM AUTHOR]

Background The purpose of this computational modeling study was to compare the volume of glenoid bone removal required to implant 3 augmented component designs for management of B2 erosions. In addition, we assessed bone quality of the supporting bone directly beneath the implants by measuring bone density and porosity. Methods Three augmented component designs—full-wedge, posterior-wedge, and posterior-step—were studied by virtual implantation in a cohort of 16 patients with B2 glenoids. B2 retroversion was corrected to 0° and 10°. The outcome variables were the volume of glenoid bone removal required for implantation and the density and porosity of the bone immediately beneath the implant. Results Implant design had a significant effect on the volume of bone removal ( P < .001). When correcting to 0°, the posterior-wedge implant removed less bone than the posterior-step ( P < .001) and the full-wedge ( P = .004). At 10° retroversion, the posterior-wedge removed less bone ( P = .029) than the posterior-step but was no different than the full-wedge ( P = .143). The residual glenoid bone density with the posterior-wedge was significantly greater than with the posterior-step ( P = .048), with no other significant differences ( P > .05). Residual glenoid bone porosity was not significantly different between implants ( P > .262). Conclusions Augmented components can provide a bone-preserving option for B2 glenoid management. Substantial variations in the volume of bone removal and the quality of the remaining glenoid bone were found between 3 different designs of augmented implants. Simulations with the posterior-wedge implant resulted in substantially less glenoid bone removal, with the remaining supporting bone being of better quality. [ABSTRACT FROM AUTHOR]

Background The purpose of this computed tomography–based study was to quantify erosions in B2 glenoids. We hypothesized that erosions do not occur symmetrically and that they have a predictable orientation. Methods This study evaluated 55 type B2 glenoid cases. Computed tomography data were used to create three-dimensional reconstructions, and point coordinates were extracted from each reconstruction for morphologic analysis of the osteoarthritic glenoid and humerus. Results There was a significant difference between the mean orientation angle (28° ± 11°) of the posterior glenoid line of erosion and the superoinferior axis ( P < .001), which resulted in the average erosion being directed toward the 8-o'clock position. On average, the erosion started 1.6 ± 3.4 mm posterior to the glenoid center point. In 35% of B2 cases, the line of erosion was curved. The mean surface area was 763 ± 296 mm 2 for the neoglenoid and 957 ± 276 mm 2 for the paleoglenoid, indicating that the neoglenoid occupied 44% ± 12% of the total glenoid area. In this cohort, the mean radius of the humeral head neoarticulation was 32 ± 6 mm, the neoglenoid radius was 37 ± 8 mm, and the paleoglenoid radius was 34 ± 7 mm. The radius of the humeral head was significantly less than that of the neoglenoid ( P < .001) and the paleoglenoid ( P = .009). In addition, the radius of the neoglenoid was significantly greater than the radius of the paleoglenoid ( P = .012). Discussion Type B2 glenoids have a predictable wear pattern, which is not axisymmetric to the glenoid superoinferior axis. In addition, the identified anatomic characteristics of B2 erosions will aid surgeons in the operative management of bone loss and may assist manufacturers in the design of augmented components. [ABSTRACT FROM AUTHOR]

Background Accurate characterization of regional variations in bone density in symmetric and asymmetric (B2) glenoid erosion patterns can assist with surgical planning, reaming, and component implantation. The purpose of this study was to characterize regional bone density and porosity in symmetric and asymmetric (B2) osteoarthritic glenoids. Methods Symmetric (n = 25) and asymmetric (B2) (n = 25) erosion patterns were compared by computed tomography–based imaging software. An orthogonal coordinate system separated each glenoid into quadrants. In addition, a linear best-fit line defined the line-of-erosion between the paleoglenoid and neoglenoid in the asymmetric cohort. All glenoids were further divided into volumes at depths of 0 to 2.5 mm and 2.5 to 5 mm. Average bone density was measured in Hounsfield units. Bone voids or cysts were included to quantify regional porosity as the fraction of void volume to total glenoid volume. Results For the symmetric cohort, there were no significant differences in bone density between quadrants at either depth ( P ≥ .089). For the asymmetric cohort, bone density was significantly higher in the posterior quadrants compared with the anterior quadrants ( P < .001), especially posteroinferiorly ( P ≤ .007) at both depths. In addition, the neoglenoid had significantly higher density and lower void fraction compared with the paleoglenoid ( P < .001). There were also significant differences in void fraction between quadrants for both cohorts, at both depths ( P ≤ .004). Conclusions This study demonstrates that osteoarthritic glenoids with symmetric erosion have uniform subarticular bone density. However, asymmetric (B2) erosion patterns have potentially important regional variations in bone density and porosity, with the densest bone with the least porosity found posteroinferiorly or in the neoglenoid region. [ABSTRACT FROM AUTHOR]

Background: Posterior glenoid defects increase the risk of glenoid component loosening after total shoulder arthroplasty (TSA). The goal of this work was to evaluate the mechanical performance of a novel posterior-step glenoid prosthesis, designed to compensate for biconcave (type B2) glenoid defects. Two prototypes (“Poly-step” and “Ti-step”) were constructed by attaching polyethylene or titanium step-blocks onto standard (STD) glenoid prostheses. We hypothesized that the mechanical performance of the experimental prostheses in the presence of a B2 defect would be similar to that of an STD prosthesis in the absence of a defect. Methods: Fifteen normal shoulder specimens were consistently loaded under simulated muscle activity while peri-glenoid bone strains were measured. In 5 specimens, arthroplasty was performed with an STD glenoid prosthesis. In the remaining 10 specimens, a 20° B2 glenoid defect was created before arthroplasty was performed with the Poly-step or Ti-step prosthesis. Results: Load-induced peri-glenoid strains after TSA with either the STD or Poly-step prosthesis did not show statistical differences as compared with the native joints (P > .05). A posterior defect decreased superior glenoid strain as compared with the intact specimens (P < .05). The change in strains after Poly-step prosthesis implantation in the presence of a biconcave glenoid defect was not different than the change induced by STD prosthesis implantation in the absence of a defect. In contrast, strains after Ti-step prosthesis implantation were statistically different from those induced by the STD and Poly-step prostheses (P < .05). Conclusions: The Poly-step prosthesis may be a viable option for treating posterior glenoid defects. [Copyright &y& Elsevier]

Copper sulphide nanocrystals (NCs) and their derivatives are rapidly gaining attention of researchers due to wide variety of exciting physical properties. These properties can be further tuned by varying morphology and incorporation of suitable elements. Here, we report a simple and facile method for the synthesis of hierarchical flower shape CuS containing 30–40 nm thick nanosheets and Ni–CuS nanocomposite with varying molar ratio of Ni to CuS. It is observed that the formation of hierarchical flower shape of CuS is significantly depend on the type of sulfur source and metal to sulfur precursor ratio. The incorporation of uniformly decorated nickel particles on CuS micro flowers increased electrochemically active sites leading to better ion diffusion kinetics. Further, the specific capacitance value of Ni–CuS (molar ratio of 0.6:1) reflected significant enhancement, more than three times (464.03 F/g at 2 A/g), than the pure CuS (132.89 F/g at 2 A/g) submicron flowers with excellent cyclic stability. CuS flowers have been synthesized using ethylene glycol as a solvent. Ni–CuS nanocomposites were synthesized from the hierarchal nanoflowers of CuS and Ni nanoparticles with varying ratio of Ni–CuS. The Ni–CuS (0.6:1) nanocomposite shows more than three times enhancement of specific capacitance value as compared to pure CuS. [Display omitted] • Synthesis of submicron flower shape CuS and Ni–CuS nanocomposite by successful incorporating Ni nanocrystal on it using a simple reflux method. • Sulfur source and the ratio of metal ion to sulfur precursor play significant role for the synthesis of submicron flower shape morphology of CuS. • At low temperature (at 80 °C) Ni–CuS nanocomposite is formed while at high temperature Ni is getting incorporated on the CuS lattice. • Ni–CuS nanocomposite (Ni to CuS molar ratio of 0.6:1) shows more than three time enhancement of specific capacitance value as compared to pure CuS. [ABSTRACT FROM AUTHOR]

Microcapsules are emerging as promising microsize drug carriers due to their remarkable deformability. Shape plays a dominant role in determining their vascular transportation. Herein, we explored the effect of the shape of the microcapsules on the in vivo biodistribution for rational design of microcapsules to achieve optimized targeting efficiency. Silk fibroin, a biocompatible, biodegradable, and abundant material, was utilized as a building block to construct biconcave discoidal and spherical microcapsules with diameter of 1.8 μm and wall thickness of 20 nm. We have compared the cytocompatibility, cellular uptake, and biodistribution of both microcapsules. Both biconcave and spherical microcapsules exhibited excellent cytocompatibility and internalization into cancer cells. During blood circulation in mice, both microcapsules showed retention in liver and kidney and most underwent renal clearance. However, we observed significantly higher accumulation of biconcave silk microcapsules in lung compared with spherical microcapsules, and the accumulation was found to be stable in lung even after 3 days. The higher concentration of biconcave discoidal microcapsules found in lung arises from pulmonary environment, margination dynamics, and enhanced deformation in bloodstream. Red blood cell (RBC)-mimicking silk microcapsules demonstrated here can potentially serve as a promising platform for delivering drugs for lung diseases.