Comparing zero-profile and conventional cage and plate in anterior cervical discectomy and fusion using finite-element modeling.

Conventional cage and plate (CCP) implants usually used in ACDF surgery, do have limitations such as the development of postoperative dysphagia, adjacent segment degeneration, and soft tissue injury. To reduce the risk of these complications, zero-profile stand-alone cage were developed. We used finite-element modeling to compare the total von Mises stress applied to the bone, disc, endplate, cage and screw when using CCP and ZPSC implants. A 3-dimensional FE (Finite element) analysis was performed to investigate the effects of the CCP implant and ZPSC on the C3 ~ T1 vertebrae. We confirmed that the maximum von Mises stress applied with ZPSC implants was more than 2 times greater in the endplate than that applied with CCP implants. The 3D analysis of the ZPSC model von Mises stress measurements of screw shows areas of higher stress in red. Although using ZPSC implants in ACDF reduces CCP implant-related sequalae such as dysphagia, we have shown that greater von Mises stress is applied to the endplate, and screw when using ZPSC implants. This may explain the higher subsidence rate associated with ZPSC implant use in ACDF. When selecting an implant in ACDF, surgeons should consider patient characteristics and the advantages and disadvantages of each implant type.

Biomechanical Effects of Different Sitting Postures and Physiologic Movements on the Lumbar Spine: A Finite Element Study.

This study used the finite element method(FEM) to investigate how pressure on the lumbar spine changes during dynamic movements in different postures: standing, erect sitting on a chair, slumped sitting on a chair, and sitting on the floor. Three load modes (flexion, lateral bending, and axial rotation) were applied to the FEM, simulating movements of the lumbar spine. Results showed no significant difference in pressure distribution on the annulus fiber and nucleus pulposus, representing intradiscal pressure, as well as on the cortical bone during movements between standing and erect sitting postures. However, both slumped sitting on a chair and sitting on the floor postures significantly increased pressure on the nucleus pulposus, annulus fibrosus, and cortical bone in all three movements when compared to standing or erect sitting on a chair. Notably, sitting on the floor resulted in even higher pressure on the nucleus pulposus and annulus fibers compared to slumped sitting on a chair. The decreased lumbar lordosis while sitting on the floor led to the highest increase in pressure on the annulus fiber and nucleus pulposus in the lumbar spine. In conclusion, maintaining an erect sitting position with increased lumbar lordosis during seated activities can effectively reduce intradiscal pressure and cortical bone stress associated with degenerative disc diseases and spinal deformities.

Rare or Overlooked Cases of Acute Acalculous Cholecystitis in Young Patients with Central Nervous System Lesion.

This case series presents two cases of acute acalculous cholecystitis (AAC)-a rare condition-in young women with central nervous system (CNS) lesions. Both patients had significant neurologic deficits and no well-known risk factors or presence of comorbidities (such as diabetes or a history of cardiovascular or cerebrovascular disease). Early diagnosis is important in cases of AAC owing to its high mortality rate; however, due to neurological deficits in our cases, accurate medical and physical examinations were limited, thereby leading to a delay in the diagnosis. The first case was of a 33-year-old woman with multiple fractures and hypovolemic shock due to a traumatic accident; she was diagnosed with hypoxic brain injury. The second case was of a 32-year-old woman with bipolar disorder and early-onset cerebellar ataxia who developed symptoms of impaired cognition and psychosis; she was later diagnosed with autoimmune encephalopathy. In the first case, the duration between symptom onset and diagnosis was 1 day, but in the second case, it was 4 days from diagnosis based on the occurrence of high fever. We emphasize that if a young woman presents with high fever, the possibility of AAC should be considered, particularly if a CNS lesion is present because it may pose difficulty in the evaluation of typical symptoms of AAC. Careful attention is thus required in such cases.

Electrophysiologic Patterns of Symptomatic Vincristine-Induced Peripheral Neuropathy in Children with Acute Lymphocytic Leukemia.

Acute lymphocytic leukemia is one of the most common cancers in children. Multi-drug chemotherapy is used for treatment, and the representative drug is vincristine. Although various side effects may occur due to vincristine, the association with peripheral neuropathy is high compared to that of other drugs. This study focused on children under the age of 18 years of age with ALL who received chemotherapy containing vincristine. We retrospectively analyzed the results of a nerve conduction study and a cumulative dose of vincristine in 30 children diagnosed with peripheral neuropathy. The average cumulative dose until diagnosis of vincristine-induced peripheral neuropathy was 14.99 ± 1.21 mg/m2, and motor nerves were predominantly involved. Additionally, a marked decrease in average amplitude was also observed in motor nerves. In addition, when the relationship between the incidence of peripheral neuropathy and the cumulative dose was analyzed through the survival curve, about 50% of children developed peripheral neuropathy at a dose of 15.5 ± 1.77 mg/m2. Based on the electrophysiological characteristics of pediatric vincristine-induced peripheral neuropathy, as well as the relationship between the incidence rate and the cumulative dose, it is possible to observe more closely the vincristine-induced peripheral neuropathy occurrence in children with ALL at an appropriate time.

Designing with relaxed skin tension line in perforator-based island flap for sacral sore reconstruction: A STROBE-compliant observational study.

Many various types of operative techniques have been performed used to treat make-up for sacral defects. Perforator-based flaps with flap transposition, but achieving an optimal flap design and tension-free flap closure without skeletonizing the perforator requires a great deal of clinical experience. In this study, we demonstrate perforator selection based on considerations of the relaxed skin tension line (RSTL), which has proven to be a suitable method of achieving an efficient flap design that enables primary closure. Twenty-five perforator-based flap procedures were performed on 25 patients at a single institution from February 2018 to January 2021. The medical records of patients were retrospectively reviewed. Twenty-three flaps survived completely. Two flaps developed partial tip necrosis but recovered after secondary healing, and 1 patient developed temporary congestion, which resolved spontaneously. No recipient or donor site recurrence or dehiscence was identified during follow-up. We report our clinical experiences of perforator-based flap use in the sacral region. When selecting an appropriate perforating vessel, 2 important points should be considered, that is, a flap long axis parallel to RSTLs and defect shape. According to the method presented in this paper, perforator-based flaps can be transposed safely and easily with few complications and serve as useful practice models to cover sacral defects.

Multifocal intraosseous calvarial hemangioma misdiagnosed as subgaleal lipoma.

Intraosseous hemangioma is a rare, slow-growing, benign tumor of blood vessels. Primary hemangioma of the skull is a benign lesion that may appear as a palpable mass or accidentally detected during image evaluation. Simple radiography is the most commonly used technique to localize a lesion and computed tomography (CT) may help determine the effect of a lesion. We report a case of multifocal intraosseous calvarial hemangioma developed in the subgaleal plane of an elderly male patient. Ultrasonography examination revealed hyperechoic striated septae parallel to the skin and discontinuity of the focal cortex, however, the underlying bone cortex appeared relatively intact. No significant flow is observed on Doppler ultrasonography. Based on these evaluations, the mass was interpreted by a radiologist as a subgaleal lipoma. This case highlights the importance of additional CT examination in a patient presenting with a scalloping sign of the underlying calvarium. Clinicians also should be aware of the possibility of intraosseous calvarial hemangiomas in lesion. Furthermore, the proper choice of congenital vascular malformation term is still quite confusing with misconception present in the literature.

Effective method for reconstruction of remaining lower lip vermilion defect after a mental V-Y advancement flap.

BACKGROUND: The mental V-Y advancement flap method is useful for reconstruction of lower lip defect because of its many advantages. However, it is not easy to select the optimal reconstructive method for the vermilion defect that remains after application of the mental V-Y advancement flap. In choosing the representative surgical method for vermilion mucosal reconstruction including mucosal V-Y advancement flap, buccal mucosal flap, and buccal mucosal graft. We describe an efficient technique to large lower lip defects combining mental V-Y advancement flap and buccal mucosal graft. METHODS: This study included 16 patients who underwent reconstructive surgery for full-thickness and large defect (> half the entire width) of the lower lip from October 2006 to September 2017. The operation was conducted using mental V-Y advancement flap with various vermilion mucosal reconstruction methods considering the location of the defect and the amount of residual tissue of the lip coloboma after excision. RESULTS: All patients underwent mental V-Y advancement flap. In vermilion mucosal reconstruction, five patients underwent mucosal V-Y advancement flap, three underwent buccal mucosal flap, and eight underwent buccal mucosal graft. There were good aesthetic and functional results in all patients who underwent buccal mucosal graft. However, two patients who underwent mucosal V-Y advancement flap complained of oral incompetence, and all patients who underwent buccal mucosal flap had oral commissure deformity. CONCLUSION: Buccal mucosal graft combined with mental V-Y advancement flap can produce suitable functional and aesthetic outcomes in near total lower lip reconstruction in patient with large mucosal defect including vermilion portion.

Comparative Measurement of Biophysical Parameters in Consideration of Skin Graft Donor Site for Nasal Defects.

BACKGROUND: In planning a skin graft, the texture, color, and size of the recipient and donor site tissues should be considered. OBJECTIVE: We determined the optimal donor sites for nasal full-thickness skin grafting based on biophysical parameters. METHODS: Thirty women over the age of 60 were selected for this study. Four recipient sites (nasal root, dorsum, tip, ala) and three donor sites (preauricle, postauricle, forehead) were considered. Biophysical parameters such as transepidermal water loss (TEWL), capacitance, sebum output, erythema/melanin value, and skin replica technique were tested. RESULTS: The nasal root was correlated with the forehead in terms of TEWL and sebum output. The nasal dorsum was correlated with the preauricle in terms of TEWL, erythema/melanin value, and skin replica measurements. The nasal tip was correlated with the preauricle in terms of TEWL, sebum output, erythema/melanin value, and skin replica measurements. The ala was correlated with the forehead in terms of TEWL and skin replica measurements. CONCLUSION: The preauricule is the optimal donor site for resurfacing of the nasal dorsum and tip. The forehead is a good donor site for alar defects. For resurfacing of the nasal root, the forehead and postauricle are good choices.

Spatial expression of claudin family members in various organs of mice.

Claudins (CLDNs) are tetraspan transmembrane proteins, which are components of tight junctions. The CLDN family is composed of 27 members that are responsible for paracellular transport and certain CLDNs form charge-selective ion channels. CLDNs have two extracellular loops, and the charge of the first extracellular loop determines the ion selectivity of each CLDN. Although the expression and function of each CLDN have been previously investigated, the distribution of CLDNs in various target organs remains to be determined. In the present study, the tissue-specific mRNA distribution of CLDNs (1-5, 7-8, 10a and b, 11-12, 14-17 and 19) in the duodenum, ileum, colon, kidney, liver and lung were defined. Among the tested CLDNs, CLDN1, 2, 12 and 16 were selected for further investiagtion. It was observed that CLDN1, CLDN2 and CLDN12 transcripts and proteins were particularly abundant in the investigated organs. Notably, immune-reactive CLDN16 was detected in a tissue-specific manner and shown in the renal tubules and portal vein. The tested CLDNs were localized to intercellular apical junctions in the epithelium of the intestine, renal tubule and bronchus. Based on this novel information, the presence of several types of CLDNs is of interest as CLDNs may promote or dampen the paracellular diffusion of specific ions.