Tongue-in-Groove: A Novel Implant Design for a Blow-Out Fracture.

Background: During blow-out fracture surgery, restoration of the orbital volume and rigid implant fixation are essential. The migration of an implant is a concern of most surgeons. The purpose of this study was to introduce a simple idea of molding and fixing an orbital implant. Methods: In the tongue-in-groove method, an incision of about 2 mm was made on the edge of the implant and it was bent to form a slot. A hole was made in the center of the implant for fitting a bone hook, and the implant was firmly fit into the remaining intact bone. Before and after surgery, computed tomography (CT) was used to evaluate changes in the orbital volume and the location of the implant. Statistically significant restoration of the orbital volume was confirmed on postoperative CT. Results: Compared with the unaffected orbital volume, the affected orbital volume was increased from 87.06 ± 7.92% before surgery to 96.14 ± 6.11% after surgery (p < 0.001). There was one case of implant migration during follow-up. However, the degree of movement was not severe, and there were no events during the follow-up period. Conclusions: The tongue-in-groove technique offers advantages, such as easy fixation of the implant, with minimal trauma to the surrounding tissues. In addition, the method offers advantages, such as being easy to learn, requiring little time for trimming the implant, and being relatively low cost. Therefore, it can be one of the options for implant fixation.

Injectable Microparticle-containing hydrogel with controlled release of bioactive molecules for facial rejuvenation.

The skin is the largest organ and a crucial barrier for protection against various intrinsic and extrinsic factors. As we age, the skin's components become more vulnerable to damage, forming wrinkles. Among different procedures, hyaluronic acid-based hydrogel has been extensively utilized for skin regeneration and reducing wrinkles. However, it has limitations like low retention and weak mechanical properties. In this study, we suggested the poly(l-lactic acid) (PLLA) microparticles containing alkaline magnesium hydroxide and nitric oxide-generating zinc oxide and rejuvenative hyaluronic acid (HA) hydrogels including these functional microparticles and asiaticoside, creating a novel delivery system for skin rejuvenation and regeneration. The fabricated rejuvenative hydrogels have exhibited enhanced biocompatibility, pH neutralization, reactive oxygen species scavenging, collagen biosynthesis, and angiogenesis capabilities in vitro and in vivo. Additionally, an excellent volume retention ability was demonstrated due to the numerous hydrogen bonds that formed between hyaluronic acid and asiaticoside. Overall, our advanced injectable hydrogel containing functional microparticles, with controlled release of bioactive molecules, has a significant potential for enhancing the regeneration and rejuvenation of the skin.

Osteoporotic Bone Regeneration via Plenished Biomimetic PLGA Scaffold with Sequential Release System.

Achieving satisfactory bone tissue regeneration in osteoporotic patients with ordinary biomaterials is challenging because of the decreased bone mineral density and aberrant bone microenvironment. In addressing this issue, a biomimetic scaffold (PMEH/SP), incorporating 4-hexylresorcinol (4HR), and substance P (SP) into the poly(lactic-go-glycolic acid) (PLGA) scaffold with magnesium hydroxide (M) and extracellular matrix (E) is introduced, enabling the consecutive release of bioactive agents. 4HR and SP induced the phosphorylation of p38 MAPK and ERK in human umbilical vein endothelial cells (HUVECs), thereby upregulating VEGF expression level. The migration and tube-forming ability of endothelial cells can be promoted by the scaffold, which accelerates the formation and maturation of the bone. Moreover, 4HR played a crucial role in the inhibition of osteoclastogenesis by interrupting the IκB/NF-κB signaling pathway and exhibiting SP, thereby enhancing the migration and angiogenesis of HUVECs. Based on such a synergistic effect, osteoporosis can be suppressed, and bone regeneration can be achieved by inhibiting the RANKL pathway in vitro and in vivo, which is a commonly known mechanism of bone physiology. Therefore, the study presents a promising approach for developing a multifunctional regenerative material for sophisticated osteoporotic bone regeneration.

Does the advantage of transcutaneous oximetry measurements in diabetic foot ulcer apply equally to free flap reconstruction?

BACKGROUND: Transcutaneous oxygen pressure (TcpO2) is a precise method for determining oxygen perfusion in wounded tissues. The device uses either electrochemical or optical sensors. AIM: To evaluate the usefulness of TcpO2 measurements on free flaps (FFs) in diabetic foot ulcers (DFUs). METHODS: TcpO2 was measured in 17 patients with DFUs who underwent anterolateral thigh (ALT)-FF surgery and compared with 30 patients with DFU without FF surgery. RESULTS: Significant differences were observed in the ankle-brachial index; duration of diabetes; and haemoglobin, creatinine, and C-reactive protein levels between the two groups. TcpO2 values were similar between two groups except on postoperative days 30 and 60 when the values in the ALT-FF group remained < 30 mmHg and did not increase > 50 mmHg. CONCLUSION: Even if the flap is clinically stable, sympathectomy due to adventitia stripping during anastomosis and arteriovenous shunt progression due to diabetic polyneuropathy could lead to low TcpO2 values in the ALT-FF owing to its thick fat tissues, which is supported by the slow recovery of the sympathetic tone following FF. Therefore, TcpO2 measurements in patients with DFU who underwent FF reconstruction may be less accurate than in those who did not.

Breast filler granuloma mistaken for implant rupture: A case report.

RATIONALE: Breast augmentation is usually performed by inserting implants into the breasts. However, injectable fillers are sometimes used for the convenience of both patients and surgeons. If foreign substances, such as biomaterials, are injected into the body, complications such as inflammation, granuloma, and tissue necrosis can occur owing to foreign body reactions. PATIENT CONCERNS: A 39-year-old female patient visited our hospital complaining of tenderness, redness, and swelling in both breasts. The patient had undergone bilateral breast augmentation using implants 4 years prior to current consult. DIAGNOSES: On magnetic resonance imaging (MRI), cystic lesions and fluid collections were observed, with findings suggesting implant rupture; hence, surgery was planned to remove both implants. INTERVENTIONS: Intraoperatively, the implant was malpositioned in the upper lateral portion without rupture. Capsular contracture findings were also not prominent. A large amount of inflammatory granuloma was observed and removed in the prepectoral plane, and the implants were immediately inserted into a new subpectoral plane. OUTCOMES: The volume of the new implant was 175 mL, which was smaller than the previous one, as per the patient preference. Cytology of the fluid from the previous implant pocket showed no evidence of malignancy, and the granuloma was identified as inflammatory tissue caused by a foreign body reaction on biopsy. The excessive protrusion of both breasts was corrected after surgery, and the patient was satisfied with the aesthetic outcomes without any complications up to 3 months after surgery. LESSONS: The use of injectable fillers for breast augmentation carries the risk of misdiagnosis, and, therefore, surgeons should always exercise caution.

Multimodal therapy strategy based on a bioactive hydrogel for repair of spinal cord injury.

Traumatic spinal cord injury results in permanent and serious neurological impairment, but there is no effective treatment yet. Tissue engineering approaches offer great potential for the treatment of SCI, but spinal cord complexity poses great challenges. In this study, the composite scaffold consists of a hyaluronic acid-based hydrogel, decellularized brain matrix (DBM), and bioactive compounds such as polydeoxyribonucleotide (PDRN), tumor necrosis factor-α/interferon-γ primed mesenchymal stem cell-derived extracellular vesicles (TI-EVs), and human embryonic stem cell-derived neural progenitor cells (NPC). The composite scaffold showed significant effects on regenerative prosses including angiogenesis, anti-inflammation, anti-apoptosis, and neural differentiation. In addition, the composite scaffold (DBM/PDRN/TI-EV/NPC@Gel) induced an effective spinal cord regeneration in a rat spinal cord transection model. Therefore, this multimodal approach using an integrated bioactive scaffold coupled with biochemical cues from PDRN and TI-EVs could be used as an advanced tissue engineering platform for spinal cord regeneration.

Prediction of diabetic foot amputation using newly revised DIRECT coding system: Comparison of accuracy with that of five existing classification systems.

Diabetes mellitus (DM) causes various complications over time, one such complication is diabetic foot ulcers (DFU), which are challenging to treat and can lead to amputation. Additionally, a system for accurate prediction of amputation has yet to be developed. In total, 131 patients were included in the study after retrospectively collecting data from 2016 to 2020 about DFU. The collected data were used for comparison of the accuracy between five existing classification systems and the newly revised DIRECT coding system, and investigation of risk factors for lower extremity amputation (LEA). The existing five classification systems and DIRECT system can effectively predict LEA. The DIRECT3 system has three elements, C-reactive protein (CRP), ulcer history (UH), and hypertension (HTN) in addition to those of the DIRECT system. It had a high predictive value and accuracy similar to that of Wagner and University of Texas (UT) on depth among the five classification systems. Among the statistically significant risk factors, duration of DM and HTN, haemoglobin (Hb), CRP, and UH showed an association with LEA. The DIRECT coding system is effective for predicting LEA and explaining appropriate treatment methods for DFU, and is widely applicable because of its user accessibility and convenience.

A long-term follow-up study of diabetic foot ulcer using micronized acellular dermal matrix.

Treating a diabetic foot ulcer (DFU) extending to the tendon or bone can be a challenge for physicians. Recent studies have shown positive results of micronized acellular dermal matrix (ADM) treatment for treating DFU. However, studies on such ADM with a long-term follow-up are rare. Thus, the objective of this study was to retrospectively analyse patients treated with micronized ADM with a long-term follow-up to assess the effectiveness of the treatment and determine the recurrence rate. The rate of success of complete healing was 62.96% and the time of complete healing was 86.96 days in this study. The recurrence rate of DFUs was 41.17% in the overall group. However, it was only 23.52% in the micronized ADM group. The average duration of recurrence was 720.50 ± 505.12 days. The recurrence rate was 50% in weight bearing areas such as the plantar and heel. It was 12.5% in toes and non-weight bearing areas. In conclusion, micronized ADM can be used to effectively treat DFUs that have invaded ligaments or bones. A close follow-up of weight bearing area wounds will allow us to identify and treat recurrence early.

Earlobe Reconstruction Using Two Opposed Periauricular Dermal Pedicled Flap.

There are several flap techniques of earlobe reconstruction. The ideal method should be a 1-stage procedure that is simple, has fewer complications, and has excellent esthetic outcomes with a proper earlobe texture and volume. We report a case of a 45-year-old man presented with skin and soft tissue defect of right ear lobule. He underwent composite graft using 2×1 cm sized stump. Two weeks later, total necrosis of graft site was observed. After that, he underwent 2 opposed periauricular dermal pedicled flap. Each flap caudally based periauricular flaps were elevated and consisted of redundant fat tissue. These flaps were sutured like sandwich and the donor sites were closured by primary repair. There was no complication as flap congestion or hematoma. After 6 months, the patient was satisfied esthetically and there was no need of additional surgical procedure. We introduce new technique of earlobe reconstruction named 2 opposed periauricular flap. This method affords reconstruction of large sized and full-thickness earlobe defect in a simple, easy manner. It provides proper texture and volume as normal earlobe. Also, it is 1-stage method not requiring skin graft or debulking procedure. Therefore, if plastic surgeon reconstructs a large defect of earlobe, our technique can be thought of as one good option.

PLLA Composites Combined with Delivery System of Bioactive Agents for Anti-Inflammation and Re-Endothelialization.

The development of a biodegradable vascular scaffold (BVS) for the treatment of cardiovascular diseases (CVDs) still requires some improvement. Among them, re-endothelialization and anti-inflammation are clinically important to restore vascular function. In this study, we proposed a coating system to deliver hydrophilic bioactive agents to BVS using nanoemulsion and drop-casting methods. The poly(L-lactide) (PLLA) scaffold containing magnesium hydroxide (MH) was coated on the surface with bioactive molecules such as polydeoxyribonucleotide (PDRN), L-arginine (Arg, R), and mesenchymal stem cell-derived extracellular vesicles (EVs). PDRN upregulates the expression of VEGF as one of the A2A receptor agonists; and Arg, synthesized into nitric oxide by intracellular eNOS, induces endothelialization. In particular, EVs, which are composed of a lipid bilayer and transfer bioactive materials such as protein and nucleic acid, regulate homeostasis in blood vessels. Such a bioactive agent coating system and its PLLA composite suggest a new platform for the treatment of cardiovascular dysfunction.

Reduced restenosis and enhanced re-endothelialization of functional biodegradable vascular scaffolds by everolimus and magnesium hydroxide.

BACKGROUND: Coronary artery disease is a cardiovascular disease with a high mortality and mortality rate in modern society. Vascular stent insertion to restore blood flow is essential to treat this disease. A fully biodegradable vascular scaffold (BVS) is a vascular poly (L-lactic acid) (PLLA) stent that is receiving growing interest as this is biodegradable in the body and does not require secondary removal surgery. However, acidic byproducts composed of PLLA produced during the biodegradation of the BVS can induce an inflammatory response. Magnesium hydroxide, a basic inorganic particle, neutralizes the acidic byproducts of PLLA.  METHODS: In this study, we investigated using a BVS coated with everolimus and surface-modified magnesium hydroxide that suppresses smooth muscle cell proliferation and protects endothelial cells, respectively. The various characteristics of the functional stent were evaluated using in vitro and in vivo analyses.  RESULTS: The BVS was successfully prepared with evenly coated everolimus and surface-modified magnesium hydroxide. A neutral pH value was maintained by magnesium hydroxide during degradation, and everolimus was released for one month. The coated BVS effectively inhibited protein adsorption and platelet adhesion, demonstrating excellent blood compatibility. In vitro analysis showed that BVS protects endothelial cells with magnesium hydroxide and selectively inhibits smooth muscle cell proliferation via everolimus treatment. The functional BVS was inserted into porcine coronary arteries for 28 days, and the results demonstrated that the restenosis and inflammation greatly decreased and re-endothelialization was enhanced as compared to others. CONCLUSIONS: This study provides new insights into the design of drug-incorporated BVS stent for coronary artery disease.

Reduction of comminuted fractures of the anterior wall of the frontal sinus using threaded Kirschner wires and a small eyebrow incision.

BACKGROUND: Frontal sinus fractures are relatively rare. Their surgical management significantly differs depending on whether the posterior wall is invaded and the clinical features vary. A bicoronal incision or endoscopic approach can be used. However, the minimally invasive approach has been attracting attention, leading us to introduce a simple and effective surgical method using multiple-threaded Kirschner wires. METHODS: All patients had isolated anterior wall fractures without nasofrontal duct impairment. The depth from the skin to the posterior wall was measured using computed tomography to prevent injury. The edge of the bone segment on the skin was marked, a threaded Kirschner wire was inserted into the center of the bone segment, and multiple Kirschner wires were gently reduced simultaneously. RESULTS: Surgery was performed on 11 patients. Among them, seven patients required additional support for appropriate fracture reduction. Therefore, a periosteal elevator was used as an adjunct through a small sub-brow incision because the reduction was incomplete with the Kirschner wire alone. The reduction results were confirmed using facial bone computed tomography 1 to 3 days postoperatively. The follow-up period was 3 to 12 months. CONCLUSION: The patients had no complications and were satisfied with the surgical results. Here we demonstrated an easy and successful procedure to reduce a pure anterior wall frontal sinus fracture via non-invasive threaded Kirschner wire reduction.

Clinical significance of early venous enhancement on CT angiography of the ischemic lower limbs.

The authors observed good clinical courses in patients with lower limb ulcers and extensive skin inflammation who showed early venous enhancement at contrast-enhanced lower extremity computed tomographic angiography. The author hypothesized that these early venous enhancements tend to occur in conditions of healthier vascular status. A total of 145 patients who met the inclusion criteria were classified based on the degree of arterial occlusion and early venous enhancement according to lower extremity angiography. Early venous enhancement correlated with age over 65 (t-score = 0.001), absence of ulcer history (t-score = 0.003), absence of amputation history (t-score = 0.004), and low ankle-brachial index (P value = .001). We confirmed that the factors related with early venous enhancement differ from the factor inducing arterial occlusion. Prior to this study, early enhancement of veins in the lower limb was thought to be an artifact. However, in this study, veins that show early enhancement are suspected of being healthier and more responsive to inflammation than those that do not show early enhancement. These findings may help to predict the clinical course and to determine therapeutic planning without additional studies. Also, it can be easily reproduced in other facilities.

Controlled vitamin D delivery with injectable hyaluronic acid-based hydrogel for restoration of tendinopathy.

Tendinopathy is a term used to describe tendon disorders that are marked by pain and a loss of function. Recent studies demonstrated that inflammation plays an important role throughout the broad spectrum of tendinopathy. Conventional treatments such as steroid injections, analgesics, and physical modalities simply give pain relief and do not alter the disease progression without the tendon regeneration effect. Tenocytes are responsible for maintaining the tendon matrix and understanding how they function is essential to studying new treatments for tendinopathy. Our previous study showed the protective effects of vitamin D (Vit D) on damaged tenocytes. Besides its well-known effects on bone metabolism, the non-classical action of Vit D is the pleiotropic effects on modulating immune function. In the present study, we developed a Vit D delivery system with hyaluronic acid (HA), which is one of the major components of the extracellular matrix that has anti-inflammation and wound-healing properties. A novel Vit D delivery system with cross-linked HA hydrogel (Gel) and Tween 80 (T80), Vit D@Gel/T80, could be a new regeneration technique for the treatment of tendinopathy. Vit D@Gel/T80 reduced TNF-α induced damage to human tenocytes in vitro. In an animal study, the Vit D@Gel/T80 injected group demonstrated tendon restoration features. As a result, this Vit D@Gel/T80 system might be a local injection material in the treatment for tendinopathy.

Enhanced Mechanical Properties and Anti-Inflammation of Poly(L-Lactic Acid) by Stereocomplexes of PLLA/PDLA and Surface-Modified Magnesium Hydroxide Nanoparticles.

Poly(L-lactic acid) (PLLA), as a biodegradable polymer, has attracted attention for use as a biomaterial. In order to apply PLLA as a cardiovascular stent, stronger mechanical properties and anti-inflammatory effects against acidic by-products are required. In this study, PLLA/PDLA stereocomplex microparticles (SC) were developed and surface-modified magnesium hydroxide (MH) nanoparticles with oligolactide were combined with these PLLA composites. The SC improved the mechanical properties of the PLLA composites through the formation of stereocomplex structures. The surface-modified MH nanoparticles showed enhanced mechanical properties due to the stereocomplex structures formed by PLLA chains and inhibited inflammatory responses by pH neutralization as a result of MH. Additionally, the MH nanoparticles containing PLLA composites had antibacterial effects and increased the viability of human vascular endothelial cells. This technology is expected to have great potential in the development of PLLA composite materials for the production of various medical devices, such as cardiovascular stents.

Nanofiber Composites as Highly Active and Robust Anodes for Direct-Hydrocarbon Solid Oxide Fuel Cells.

Direct utilization of methane fuels in solid oxide fuel cells (SOFCs) is a key technology to realize the immediate inclusion of such high-efficiency fuel cells into the current electricity generation infrastructure. However, the broad commercialization of direct-methane fueled SOFCs is critically hindered by the inadequate electrode activity and their poor longevity, which primarily stems from the carbon build-up issues. To make the technology more competitive, a novel electrode structure that can dramatically improve the tolerance against coking is essential. Herein, we present highly active and robust core-shell nanofiber anodes, La0.75Sr0.25Cr0.5Mn0.5O3@Sm0.2Ce0.8O1.9 (LSCM@SDC), directly obtained with a single-nozzle electrospinning process through the use of two immiscible polymers. The intimate coverage of SDC on LSCM not only increases the active reaction sites but also promotes resistance toward carbon deposition and thermal aggregation. As such, the electrode polarization resistance obtained with LSCM@SDC NFs is among the lowest value ever reported with LSCM derivatives (∼0.11 Ω cm2 in wet H2 at 800 °C). The facile fabrication process of such complex heterostructures developed in this work is attractive for the design of not only SOFC electrodes but also other solid-state devices such as electrolysis cells, membrane reformers, and protonic cells.

Bioactive PCL microspheres with enhanced biocompatibility and collagen production for functional hyaluronic acid dermal fillers.

Polymeric microspheres containing magnesium hydroxide (MH) and a bioactive agent (BA), such as apocynin (APO) and astaxanthin (ATX), have been prepared as functional dermal fillers with enhanced physicochemical and biological performance. In this study, polycaprolactone (PCL)-based microspheres were produced with a uniform size of about 30-40 µm by utilizing a membrane emulsification device. MH from the PCL/MH microspheres effectively neutralized acidic products from PCL degradation. For in vitro cell experiments, when acidic degradation products (6-hydroxycaproic acid, HCA) were treated with MH, the acidic pH was neutralized to induce wound healing and suppress inflammation. The microspheres comprised of BA had a sustained release of the BA, without an initial burst release. Remarkably, the ATX added into the microspheres was maintained for 16 weeks and displayed positive attributes, such as tissue regeneration and collagen production improvement, as noted by in vivo testing. Overall, these results suggest that the bioactive PCL microspheres containing ATX have excellent potential as a functional dermal filler for skin aesthetics and facial plastic surgery.

Pathophysiologic Review of Blow-Out Fracture and Blow-Out Fracture Extended to Subarachnoid Space Due to Air Gun Injury.

ABSTRACT: Blow-out fracture is usually caused by direct traumatic events in the periorbital area. But in this case, the authors introduce a case in which the medial orbital wall was fractured directly through the medial rectus muscle by high pressure air gun.A 38-year-old man was injured in his right periorbital area after being hit by high pressure air gun. He had mild ecchymosis and subconjunctival hemorrhage. He had a normal light reflex and intraocular pressure of 14 mm Hg. A facial computed tomography scan confirmed a blow-out fracture of the medial orbital floor with multiple extensive subcutaneous emphysema in the right hemifacial area. Free air was also seen near the basal cistern and Sylvian fissure, indicating a pneumocephalus. The operation was performed after swelling and emphysema were subsided. Intraoperative, medial rectus muscle was damaged. After the operation, no abnormal findings were observed in the ophthalmic examination. Also, the free air findings, which were observed in preoperative x-ray, have disappeared.This case is a rare case in which an orbital wall has been fractured directly through the medial rectus muscle due to an air gun injury. Therefore, we should always kept in mind that blow-out fractures can occur even with unusual mechanisms.

Clinical features and literature review related to the material differences in thread rhinoplasty: Two case reports.

BACKGROUND: Thread rhinoplasty can trigger a reaction to thread material, which is a foreign body. We compared clinical features induced by absorbable and non-absorbable threads following thread rhinoplasty. CASE SUMMARY: Two patients who underwent different thread materials showed different clinical courses and different Hounsfield unit (HU) values in computed tomography. Patients with absorbable thread showed high HU values similar to a metallic material, and the HU value of inflammation was similar to vascular tissues with a lot of water (250). In the intraoperative field, absorbable thread materials and micro-abscesses were observed. In contrast, in the case of a non-absorbable thread, an object presumed to be thread was seen on the computed tomography (CT), and the HU value of inflammatory tissues was less than 100. In both patients, post-operative HU decreased to less than 100 and the clinical course improved. In both cases, histopathologic findings revealed foreign body granuloma associated with inflammation. CONCLUSION: Absorbable threads were more aggressive and are more easily detected on CT.

Advanced PLGA hybrid scaffold with a bioactive PDRN/BMP2 nanocomplex for angiogenesis and bone regeneration using human fetal MSCs.

Biodegradable polymers have been used with various systems for tissue engineering. Among them, poly(lactic-co-glycolic) acid (PLGA) has been widely used as a biomaterial for bone regeneration because of its great biocompatibility and biodegradability properties. However, there remain substantial cruxes that the by-products of PLGA result in an acidic environment at the implanting site, and the polymer has a weak mechanical property. In our previous study, magnesium hydroxide (MH) and bone extracellular matrix are combined with a PLGA scaffold (PME) to improve anti-inflammation and mechanical properties and osteoconductivity. In the present study, the development of a bioactive nanocomplex (NC) formed along with polydeoxyribonucleotide and bone morphogenetic protein 2 (BMP2) provides synergistic abilities in angiogenesis and bone regeneration. This PME hybrid scaffold immobilized with NC (PME/NC) achieves outstanding performance in anti-inflammation, angiogenesis, and osteogenesis. Such an advanced PME/NC scaffold suggests an integrated bone graft substitute for bone regeneration.