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Cureus May 2024This case report aims to present the successful reconstruction of a nasal defect in a 56-year-old male patient who suffered a partial nasal amputation due to a domestic...
This case report aims to present the successful reconstruction of a nasal defect in a 56-year-old male patient who suffered a partial nasal amputation due to a domestic accident involving a grinding wheel. The reconstruction was carried out using a paramedian frontal flap in a two-stage surgical process. Initially, the flap was designed and customized to match the dimensions of the defect, with a pedicle width of approximately 1.5 cm vertically. The flap was elevated in a distal-to-proximal manner, starting with subcutaneous dissection and progressing to periosteal dissection proximally. Weekly dressing changes were made using fatty gauze and fusidic acid ointment. Four weeks postoperatively, the flap pedicle was divided, and the brow was repositioned. At the six-month follow-up, the patient showed satisfactory clinical outcomes with no functional complaints and was very pleased with the aesthetic result. Paramedian frontal flap reconstruction is a dependable technique for addressing nasal defects following traumatic amputation, providing favorable functional and aesthetic results. This case highlights the importance of careful surgical planning and technique in achieving successful facial reconstruction.
PubMed: 38803405
DOI: 10.7759/cureus.61167 -
Orthopedic Research and Reviews 2024To study the peculiarities of peroneal stump remodelling after transtibial amputation in the process of prosthesis usage.
AIM
To study the peculiarities of peroneal stump remodelling after transtibial amputation in the process of prosthesis usage.
MATERIAL AND METHODS
A histological study of the ends of the stumps of the fibula in 68 patients was performed. Terms after amputation: 2-8 years.
RESULTS
In the 1st group the stumps with the reparative process completion were formed. In the 2nd group there were sharp disturbances of the reparative process with the formation of the cone-shaped end. In the 3rd group there was a pronounced periosteal bone formation with changes in the shape and structure of bone tissue and incompleteness of the reparative process.
CONCLUSION
Absence of balloting of the fibula stump and dense overlapping of the medullary cavity by muscles promotes complete remodelling of the fibula remnant with preservation of its organicity. Pathological remodelling of the fibula stump occurs due to its hypermobility, repeated traumatisation of the forming regenerate, neuritis of the peroneal nerve, osteogenesis disorders and structural and functional mismatch of the bone tissue to the loading conditions in the prosthesis. Morphological signs of pathological remodelling are the lack of completion of reparative regeneration, intensive bone tissue remodelling lasting for years with pronounced resorption and appearance of immature bone structures, fractures of the cortical diaphyseal layer, residual limb deformities with formation of a functional regenerates, narrowing and closure of the medullary canal with conglomerate with soft tissue inclusions. The anatomical inferiority of bone tissue formed in the process of remodelling of the fibula remnant creates a threat of stress fracture.
PubMed: 38799026
DOI: 10.2147/ORR.S459927 -
BioRxiv : the Preprint Server For... May 2024Mechanical loading is required for bone health and results in skeletal adaptation to optimize strength. Local nerve axons, particularly within the periosteum, may...
Mechanical loading is required for bone health and results in skeletal adaptation to optimize strength. Local nerve axons, particularly within the periosteum, may respond to load-induced biomechanical and biochemical cues. However, their role in the bone anabolic response remains controversial. We hypothesized that spatial alignment of periosteal nerves with sites of load-induced bone formation would clarify this relationship. To achieve this, we developed RadialQuant, a custom tool for spatial histomorphometry. Tibiae of control and neurectomized (sciatic/femoral nerve cut) pan-neuronal Baf53b-tdTomato reporter mice were loaded for 5-days. Bone formation and periosteal nerve axon density were then quantified simultaneously in non-decalcified sections of the mid-diaphysis using RadialQuant. In control animals, anabolic loading induced maximal periosteal bone formation at the site of peak compression, as has been reported previously. Loading did not significantly change overall periosteal nerve density. However, a trending 28% increase in periosteal axons was noted at the site of peak compression in loaded limbs. Neurectomy depleted 88% of all periosteal axons, with near-total depletion on load-responsive surfaces. Neurectomy alone also caused de novo bone formation on the lateral aspect of the mid-diaphysis. However, neurectomy did not inhibit load-induced increases in periosteal bone area, mineralizing surface, or bone formation rate. Rather, neurectomy spatially redistributed load-induced bone formation towards the lateral tibial surface with a reduction in periosteal bone formation at the posterolateral apex (-63%) and enhancement at the lateral surface (+1360%). Altogether, this contributed to comparable load-induced changes in cortical bone area fraction (+4.4% in controls; +5.4% in neurectomized). Our results show that local skeletal innervation modulates but is not required for skeletal adaptation to applied load. This supports the continued use of loading and weight-bearing exercise as an effective strategy to increase bone mass, even in patients with peripheral nerve damage or dysfunction.
PubMed: 38798585
DOI: 10.1101/2024.05.12.593761 -
Cancers May 2024Osteosarcoma may arise as a secondary cancer following leukemias or lymphomas. We intended to increase the knowledge about such rare events.
Osteosarcoma Arising as a Secondary Malignancy following Treatment for Hematologic Cancer: A Report of 33 Affected Patients from the Cooperative Osteosarcoma Study Group (COSS).
PURPOSE
Osteosarcoma may arise as a secondary cancer following leukemias or lymphomas. We intended to increase the knowledge about such rare events.
PATIENTS AND METHODS
We searched the Cooperative Osteosarcoma Study Group's database for individuals who developed their osteosarcoma following a previous hematological malignancy. The presentation and treatment of both malignancies was investigated, and additional neoplasms were noted. Outcomes after osteosarcoma were analyzed and potential prognostic factors were searched for.
RESULTS
A total of 33 eligible patients were identified (male: 23, female: 10; median age: 12.9 years at diagnosis of hematological cancer; 20 lymphomas, 13 leukemias). A cancer predisposition syndrome was evident in one patient only. The hematological cancers had been treated by radiotherapy in 28 (1 unknown) and chemotherapy in 26 cases, including bone-marrow transplantation in 9. The secondary bone sarcomas (high-grade central 27, periosteal 2, extra-osseous 2, undifferentiated pleomorphic sarcoma of bone 2) arose after a median lag-time of 9.4 years, when patients were a median of 19.1 years old. Tumors were considered radiation-related in 26 cases (1 unknown). Osteosarcoma-sites were in the extremities (19), trunk (12), or head and neck (2). Metastases at diagnosis affected eight patients. Information on osteosarcoma therapy was available for 31 cases. All of these received chemotherapy. Local therapy involved surgery in 27 patients, with a good response reported for 9/18 eligible patients. Local radiotherapy was given to three patients. The median follow-up was 3.9 (0.3-12.0) years after bone tumor diagnosis. During this period, 21 patients had developed events as defined, and 15 had died, resulting in 5-year event-free and overall survival rates of 40% (standard error: 9%) and 56% (10%), respectively. There were multiple instances of additional neoplasms. Several factors were found to be of prognostic value ( < 0.05) for event-free (osteosarcoma site in the extremities) or overall (achievement of a surgical osteosarcoma-remission, receiving chemotherapy for the hematologic malignancy) survival.
CONCLUSIONS
We were able to prove radiation therapy for hematological malignancies to be the predominant risk factor for later osteosarcomas. A resulting overrepresentation of axial and a tendency towards additional neoplasms affects prognosis. Still, selected patients may become long-term survivors with appropriate therapies, which is an argument against therapeutic negligence.
PubMed: 38791915
DOI: 10.3390/cancers16101836 -
JCI Insight May 2024We present a transcriptomic analysis that provides a better understanding of regulatory mechanisms within the healthy and injured periosteum. The focus of this work is...
We present a transcriptomic analysis that provides a better understanding of regulatory mechanisms within the healthy and injured periosteum. The focus of this work is on characterizing early events controlling bone healing during formation of periosteal callus on day 3 post fracture. Building upon our previous findings showing that induced Notch1 signaling in osteoprogenitors leads to better healing, we compared samples in which Notch 1 intracellular domain is overexpressed by periosteal stem/progenitor cells with control intact and fractured periosteum. Molecular mechanisms and changes in skeletal stem/progenitor cells (SSPCs) and other cell populations within the callus, including hematopoietic lineages were determined. Notably, Notch ligands were differentially expressed in endothelial and mesenchymal populations, with Dll4 restricted to endothelial cells, whereas Jag1 was expressed by mesenchymal populations. Targeted deletion of Dll4 in endothelial cells using Cdh5CreER resulted in negative effects on early fracture healing, while deletion in SSPCs using α-smooth muscle actin-CreER did not impact bone healing. Translating these observations into clinically relevant model of bone healing revealed the beneficial effects of delivering Notch ligands alongside osteogenic inducer, BMP2. These findings provide insights into the regulatory mechanisms within the healthy and injured periosteum, paving the way for novel translational approaches to bone healing.
PubMed: 38781018
DOI: 10.1172/jci.insight.181073 -
PeerJ 2024In the Western Scheldt Estuary near the Belgian-Dutch border, middle to late Eocene strata crop out at the current seafloor. Most vertebrae of large Eocene basilosaurid... (Comparative Study)
Comparative Study
In the Western Scheldt Estuary near the Belgian-Dutch border, middle to late Eocene strata crop out at the current seafloor. Most vertebrae of large Eocene basilosaurid taxa from this area were previously described in several papers. They represent three morphotypes: elongated vertebrae of a large species of (Morphotype 1b), a not-elongated vertebra of a large 'dorudontid' basilosaurid (Morphotype 2) and 'shortened' vertebrae of a new, unnamed taxon (Morphotype 3). This article deals with a still undescribed, smaller vertebra, NMR-16642, from this site. Our first aim was to date it by dinoflagellate cysts in adhering sediments. Yielding an age of about 38 Ma, it is one of the very few remains of basilosaurids from Europe, of which the age could be assessed with reasonable certainty. The vertebra, Morphotype 1a, is assigned to a small species of . High-quality CT scans are used to differentiate between NMR-16642, Morphotype 1a, and the large species of Morphotype 1b. Another aim of this paper is to investigate the inner structure and vascularity of the study vertebra and that of the other morphotypes (1b, 2, 3) from this area by using high-quality CT scans. Notwithstanding differences in size, shape and compactness, the vertebral inner structure with a multi-layered cortex of periosteal bone, surrounding two cones of endosteal bone appears to be basically similar in all morphotypes. Apparently, this inner structure reflects the ontogenetic vertebral growth. An attempt to reconstruct the vascularity of the vertebrae reveals a remarkable pattern of interconnected vascular systems. From the dorsal and, if present, ventral foramina, vascular canals are running to a central vascular node. From this node a system of vascular canals goes to the epiphyseal ends, giving rise to separate systems for cortex and cones. It is the first time that the vascularity of vertebrae of archaeocetes is investigated.
Topics: Animals; Spine; Fossils; North Sea; Dinosaurs; Tomography, X-Ray Computed
PubMed: 38774542
DOI: 10.7717/peerj.16541 -
The Saudi Dental Journal May 2024Prescribing antibiotics (AB) before or after third molar surgery is common among dentists and oral surgeons; however the effectiveness of AB therapy in reducing surgery...
BACKGROUND
Prescribing antibiotics (AB) before or after third molar surgery is common among dentists and oral surgeons; however the effectiveness of AB therapy in reducing surgery complications is still contradictory.
AIM
The aim of this study is to evaluate the healing process after mandibular third molar surgery without AB therapy and to assess the role of close follow-ups on patient's perspective.
METHODS
This study is a semi-empirical, prospective study conducted on 79 healthy patients. After surgical extraction of the impacted or semi-erupted mandibular third molar, assessment of pain, swelling (intergonial width), infection, and sub-periosteal abscess was done during the 1-month follow-ups of patients.
RESULTS
The mean difficulty level of surgeries performed in this study was moderate. A significant relationship was found between the pain intensity and the psychological impact of follow-ups (p < 0.05). No fever or sign of infection were seen in any patient. The amount of swelling was significantly related to the difficulty level of surgery (p = 0.001); however, no significant correlation was found between the amount of pain and the level of difficulty.
CONCLUSION
Within the limitations of this study, it can be concluded that in order to reduce the hazards of AB therapy, close follow-up of patients after surgery can be advised.
PubMed: 38766279
DOI: 10.1016/j.sdentj.2024.02.004 -
Scientific Reports May 2024Gradual elevation of the periosteum from the original bone surface, based on the principle of distraction osteogenesis, induces endogenous hard and soft tissue...
Gradual elevation of the periosteum from the original bone surface, based on the principle of distraction osteogenesis, induces endogenous hard and soft tissue formation. This study aimed to assess the impact of alternating protocols of activation with relaxation (periosteal pumping) on bone modeling and remodeling. One hundred and sixty-two adult male Wistar rats were used in this study. Four test groups with different pumping protocols were created based on the relaxation applied. Two control groups underwent an activation period without relaxation or only a single activation. One group was sham-operated. Periosteal pumping without period of activation induced gene expression in bone and bone remodeling, and following activation period enhanced bone modeling. Four test groups and control group with activation period equaled the values of bone modeling at the end-consolidation period, showing significant downregulation of Sost in the bone and periosteum compared to that in the sham group (p < 0.001 and p < 0.001, respectively). When all test groups were pooled together, plate elevation from the bony surface increased bone remodeling on day 45 of the observation period (p = 0.003). Furthermore, bone modeling was significantly affected by plate elevation on days 17 and 45 (p = 0.047 and p = 0.005, respectively) and by pumping protocol on day 31 (p = 0.042). Periosteal pumping was beneficial for increasing bone repair when the periosteum remained in contact with the underlaying bony surface during the manipulation period. Following periosteal elevation, periosteal pumping accelerated bone formation from the bony surface by the modeling process.
Topics: Animals; Periosteum; Male; Bone Remodeling; Rats, Wistar; Rats; Osteogenesis; Osteogenesis, Distraction
PubMed: 38750119
DOI: 10.1038/s41598-024-61902-w -
PloS One 2024Entheses are classified into three types: fibrocartilaginous, fibrous, and periosteal insertions. However, the mechanism behind the development of fibrous entheses and...
Entheses are classified into three types: fibrocartilaginous, fibrous, and periosteal insertions. However, the mechanism behind the development of fibrous entheses and periosteal insertions remains unclear. Since both entheses are part of the temporomandibular joint (TMJ), this study analyzes the TMJ entheses. Here, we show that SOX9 expression is negatively regulated during TMJ enthesis development, unlike fibrocartilage entheses which are modularly formed by SCX and SOX9 positive progenitors. The TMJ entheses was adjacent to the intramembranous bone rather than cartilage. SOX9 expression was diminished during TMJ enthesis development. To clarify the functional role of Sox9 in the development of TMJ entheses, we examined these structures in TMJ using Wnt1Cre;Sox9flox/+ reporter mice. Wnt1Cre;Sox9flox/+ mice showed enthesial deformation at the TMJ. Next, we also observed a diminished SOX9 expression area at the enthesis in contact with the clavicle's membranous bone portion, similar to the TMJ entheses. Together, these findings reveal that the timing of SOX9 expression varies with the ossification development mode.
Topics: SOX9 Transcription Factor; Animals; Mice; Temporomandibular Joint; Osteogenesis; Down-Regulation; Fibrocartilage; Mice, Transgenic
PubMed: 38728328
DOI: 10.1371/journal.pone.0301080 -
Frontiers in Endocrinology 2024The first evidence of the existence of vitamin A was the observation 1881 that a substance present in small amounts in milk was necessary for normal development and... (Review)
Review
The first evidence of the existence of vitamin A was the observation 1881 that a substance present in small amounts in milk was necessary for normal development and life. It was not until more than 100 years later that it was understood that vitamin A acts as a hormone through nuclear receptors. Unlike classical hormones, vitamin A cannot be synthesized by the body but needs to be supplied by the food as retinyl esters in animal products and ß-carotene in vegetables and fruits. Globally, vitamin A deficiency is a huge health problem, but in the industrialized world excess of vitamin A has been suggested to be a risk factor for secondary osteoporosis and enhanced susceptibility to fractures. Preclinical studies unequivocally have shown that increased amounts of vitamin A cause decreased cortical bone mass and weaker bones due to enhanced periosteal bone resorption. Initial clinical studies demonstrated a negative association between intake of vitamin A, as well as serum levels of vitamin A, and bone mass and fracture susceptibility. In some studies, these observations have been confirmed, but in other studies no such associations have been observed. One meta-analysis found that both low and high serum levels of vitamin A were associated with increased relative risk of hip fractures. Another meta-analysis also found that low levels of serum vitamin A increased the risk for hip fracture but could not find any association with high serum levels of vitamin A and hip fracture. It is apparent that more clinical studies, including large numbers of incident fractures, are needed to determine which levels of vitamin A that are harmful or beneficial for bone mass and fracture. It is the aim of the present review to describe how vitamin A was discovered and how vitamin A is absorbed, metabolized and is acting as a ligand for nuclear receptors. The effects by vitamin A in preclinical studies are summarized and the clinical investigations studying the effect by vitamin A on bone mass and fracture susceptibility are discussed in detail.
Topics: Humans; Bone Density; Vitamin A; Animals; Fractures, Bone; Signal Transduction; Osteoporosis; Vitamin A Deficiency; Bone and Bones
PubMed: 38711977
DOI: 10.3389/fendo.2024.1298851