Cartilaginous Components Research Articles

Molecular confirmation that fibrocartilaginous dysplasia is a variant of fibrous dysplasia

AimsFibrocartilaginous dysplasia (FCD) is a subvariant of fibrous dysplasia (FD). This study aims to retrospectively elucidate the clinicopathological and separate genetic features of the cartilaginous and fibro-osseous components of FCD.MethodsIn...

Anatomy of the Naviculocuneiform Joint Complex.

The purpose of this study was to quantify the articular surfaces of the naviculocuneiform (NC) joint to help clinicians better understand common pathologies observed such as navicular stress fractures and arthrodesis nonunions. Twenty cadaver NC joints were dissected and the articular cartilage of the navicular, medial, middle, and lateral cuneiforms were quantified by calibrated digital imaging software. Statistical analysis included calculating the mean cartilage surface area dimensions of the distal navicular and proximal cuneiform bones. Length measurements on the navicular were obtained to estimate the geographic location of the interfacet ridges. Lastly, all facets of the articular surfaces were described in regard to the shape and location of cartilaginous or fibrous components. Results were compared using Student t tests. Navicular cartilage was present over 75.4% of the surface area of the proximal NC joint, compared with 72.6% of combined cuneiform cartilage distally. The mean height of the deepest (dorsal-plantar) measurement of navicular articular cartilage was 18 ± 3 mm. The mean heights of the distal medial, middle, and lateral cuneiform articular facets were 15 ± 1 mm, 17 ± 2 mm, and 15 ± 2 mm, respectively. There is significant variation among the articular surfaces of the NC joint. Additionally, the central third of the navicular was calculated to lie in the inter-facet ridge between the medial and middle articular facets of the navicular. Surgeons may consider this study data when performing joint preparation for NC arthrodesis as cartilage was present to a mean depth of 18 mm at the NC joint. Additionally, this study demonstrates that the central third of the navicular, where most navicular stress fractures occur, lies in the interfacet ridge between the medial and middle articular facets of the navicular.

Collagen type X expression and chondrocyte hypertrophic differentiation during OA and OS development.

Chondrocyte hypertrophy and the expression of its specific marker, the collagen type X gene (COL10A1), constitute key terminal differentiation stages during endochondral ossification in long bone development. Mutations in the COL10A1 gene are known to cause schmid type metaphyseal chondrodysplasia (SMCD) and spondyloepiphyseal dyschondrodysplasia (SMD). Moreover, abnormal COL10A1 expression and aberrant chondrocyte hypertrophy are strongly correlated with skeletal diseases, notably osteoarthritis (OA) and osteosarcoma (OS). Throughout the progression of OA, articular chondrocytes undergo substantial changes in gene expression and phenotype, including a transition to a hypertrophic-like state characterized by the expression of collagen type X, matrix metalloproteinase-13, and alkaline phosphatase. This state is similar to the process of endochondral ossification during cartilage development. OS, the most common pediatric bone cancer, exhibits characteristics of abnormal bone formation alongside the presence of tumor tissue containing cartilaginous components. This observation suggests a potential role for chondrogenesis in the development of OS. A deeper understanding of the shifts in collagen X expression and chondrocyte hypertrophy phenotypes in OA or OS may offer novel insights into their pathogenesis, thereby paving the way for potential therapeutic interventions. This review systematically summarizes the findings from multiple OA models (e.g., transgenic, surgically-induced, mechanically-loaded, and chemically-induced OA models), with a particular focus on their chondrogenic and/or hypertrophic phenotypes and possible signaling pathways. The OS phenotypes and pathogenesis in relation to chondrogenesis, collagen X expression, chondrocyte (hypertrophic) differentiation, and their regulatory mechanisms were also discussed. Together, this review provides novel insights into OA and OS therapeutics, possibly by intervening the process of abnormal endochondral-like pathway with altered collagen type X expression.

Nicotinamide mononucleotide enhances fracture healing by promoting skeletal stem cell proliferation.

The process of skeletal regeneration initiated by stem cells following injury, especially in fractures, is significantly impaired by aging and adverse factors. Nicotinamide mononucleotide (NMN), a critical endogenous precursor of nicotinamide adenine dinucleotide (NAD), has garnered extensive attention for its multifaceted regulatory functions in living organisms and its wide-ranging therapeutic potential. However, whether NMN contributes to trauma-induced skeletal regeneration remains unclear. Methods: The transverse femoral shaft fracture model was employed to evaluate the potential advantages of NMN administration for overall repair during the initial fracture stages in male mice through micro-CT analysis, histochemistry, and biomechanical testing. The pro-proliferative function of NMN on skeletal stem cells (SSCs) was investigated through flow cytometry, qRT-PCR, NAD content measurement, and cell proliferation assay. Results: In this study, we observed that the administration of NMN during the initial phase of fracture in mice led to a larger callus and corresponding improvement in micro-CT parameters. NMN enhances the cartilaginous component of the callus by elevating the NAD content, consequently accelerating subsequent endochondral ossification and the fracture healing process. Subsequent analyses elucidated that NMN was beneficial in promoting the expansion of diverse stem cells in vivo and in vitro potentially via modulation of the Notch signaling pathway. Moreover, the depletion of macrophages profoundly obstructs the proliferation of SSCs. Conclusion: Our discoveries provide a potential strategy for enhancing fracture healing through stimulation of callus SSC proliferation at an early stage, shedding light on the translational value of NMN as an enhancer for skeletal regeneration and highlighting the pivotal role of macrophage-stem cell interactions in governing the regenerative influence of NMN on stem cells.

Gradient myopic defocus causes scleral tissue reinforcement and structural scleral remodelling

Aims/Purpose: To determine histological effects of lens induced refractive change on scleral remodelling in chicks.Methods: 18 Ross‐Ross chicks were raised for 14 days on a 14 hr light/10 hr dark cycle. 6 chicks were allowed to develop normally. 6 chicks wore conventional ‐10D lenses for the full 14 days. 6 chicks wore conventional ‐10D lenses for the first 7 days and myopia progression control (MPC) lenses or the next 7 days. MPC lenses had a central power of ‐10D and a gradient power rise at pupil edge (+ 2.75D). Birds were euthanized after 14 days and eyes were routinely processed for histopathological evaluation. Whole mount H&E‐stained tissue sections were microscopically analysed using bright field microscopy.Results: All lens treated birds developed significant myopia as expected Total scleral thickness was significantly reduced in the group wearing conventional ‐10 lenses (p < 0.05), but remained comparable to the normal control group for the MPC lenses treated birds. New appositional growth of the cartilaginous sclera was observed in all MPC lenses treated eyes and only in those eyes. The thickness of the cartilaginous component of the sclera was 135 ± 6, 153 ± 5, 125 ± 8 μm for conventional myopic, MPC lenses treated, and control birds respectively. There was a significant increase in the cartilaginous scleral thickness in the MPC lenses treated birds compared to the other two groups (p < 0.03), but not between the conventional ‐10D lens treated and control birds (p > 0.05).Conclusions: It is possible to induce appositional growth in hyaline cartilage in the chick sclera. In our study, this has only been achieved by using MPC lenses to reverse previously induced experimental myopia with conventional minus lenses. Our finding suggests that gradient decrease in peripheral lens power and the resulting differential level of defocus it causes could be a potential trigger of scleral reinforcement through stimulation of cartilage growth in the chick sclera.

Hip Morphology on Post-Reduction MRI Predicts Residual Dysplasia 10 Years After Open or Closed Reduction.

There is limited evidence supporting the value of morphological parameters on post-reduction magnetic resonance imaging (MRI) to predict long-term residual acetabular dysplasia (RAD) after closed or open reduction for the treatment of developmental dysplasia of the hip (DDH). We performed a retrospective study of 42 patients (47 hips) undergoing open or closed reduction with a minimum 10 years of follow-up; 39 (83%) of the hips were in female patients, and the median age at reduction was 6.3 months (interquartile range [IQR], 3.3 to 8.9 months). RAD was defined as additional surgery with an acetabular index >2 standard deviations above the age- and sex-specific population-based mean value or Severin classification grade of >2 at last follow-up. Acetabular version and depth-width ratio, coronal and axial femoroacetabular distance, cartilaginous and osseous acetabular indices, transverse ligament thickness, and the thickness of the medial and lateral (limbus) acetabular cartilage were measured on post-reduction MRI. At the time of final follow-up, 24 (51%) of the hips had no RAD; 23 (49%) reached a failure end point at a median of 11.4 years (IQR, 7.6 to 15.4 years). Most post-reduction MRI measurements, with the exception of the cartilaginous acetabular index, revealed a significant distinction between the group with RAD and the group with no RAD when mean values were compared. The coronal femoroacetabular distance (area under the receiver operating characteristic curve [AUC], 0.95; 95% confidence interval [CI], 0.90 to 1.00), with a 5-mm cutoff, and limbus thickness (AUC, 0.91; 95% CI, 0.83 to 0.99), with a 4-mm cutoff, had the highest discriminatory ability. A 5-mm cutoff for the coronal femoroacetabular distance produced 96% sensitivity (95% CI, 78% to 100%), 83% specificity (95% CI, 63% to 95%), 85% positive predictive value (95% CI, 65% to 96%), and 95% negative predictive value (95% CI, 76% to 100%). A 4-mm cutoff for limbus thickness had 96% sensitivity (95% CI, 78% to 100%), 63% specificity (95% CI, 41% to 81%), 71% positive predictive value (95% CI, 52% to 86%), and 94% negative predictive value (95% CI, 70% to 100%). Coronal femoroacetabular distance, a quantitative metric assessing a reduction's concentricity, and limbus thickness, a quantitative metric assessing the acetabulum's cartilaginous component, help to predict hips that will have RAD in the long term after closed or open reduction. Diagnostic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Gliosarcoma with Complete Osteosarcomatous Differentiation and Extensive Calcification: Case Report

Gliosarcoma is a rare malignant tumor, grade IV according to WHO. It presents malignant biphasic glial and sarcomatous components. Calcifications and ossification are uncommon findings in these tumors. We reported a rare case of gliosarcoma with extense osseous differentiation and dystrophic calcification. A 51- year-old man that presented intense headache, visual alterations, and with an observed temporal right lobe tumor. He was surgically operated and the histopathological diagnosis was a gliosarcoma with osseous and cartilaginous component. He received radiotherapy with a total dose of 66 grays (GY) in 30 fractions. He then was hospitalized again due to intense headache and pyramidal syndrome. He was surgically intervened and an enormous indurated tumor that showed only dystrophic calcifications, osseous spikes, extensive necrosis and ghost glial cells was observed. Few viable neoplastic cells were determined. This tumor showed loss of Glial acidic fibrillary protein (GFAP), and Vimentin, Ostecondrin, Osteoponin, Ki-67, and blood vessel immunoexpression. Now, it is known that the effect of radiotherapy has influence in the development of tumors (specially in gliomas), but regression with extensive osseous dystrophic calcification after therapy can rarely be observed. Some authors refer to these as “tumoral stones”. Extensive calcification could be a sign of a good prognosis as it facilitates extirpation during surgery, although a broaden study in this topic is necessary to affirm this sentence. This is a rare case of gliosarcoma with rapid involution of tumor and stone formation secondary to radiotherapy.

NKX3.1 immunohistochemistry and methylome profiling in mesenchymal chondrosarcoma: additional diagnostic value for a well-defined disease?

Mesenchymal chondrosarcoma (MCS) is a rare and highly aggressive tumour of soft tissue and bone that is defined by an underlying and highly specific fusion transcript involving HEY1 and NCOA2. Histologically, the tumours show a biphasic appearance consisting of an undifferentiated blue and round cell component as well as islands of highly differentiated cartilage. Particularly in core needle biopsies, the chondromatous component can be missed and the non-specific morphology and immunophenotype of the round cell component can cause diagnostic challenges. We applied NKX3.1 immunohistochemistry which was recently reported as a highly specific marker as well as methylome and copy number profiling to a set of 45 well characterised MCS cases to evaluate their potential diagnostic value. Methylome profiling revealed a highly distinct cluster for MCS. Notably, the findings were reproducible also when analysing the round cell and cartilaginous component separately. Furthermore, four outliers were identified by methylome profiling for which the diagnosis had to be revised. NKX3.1 immunohistochemistry showed positivity in 36% of tumours, the majority of which was rather focal and weak. Taken together, NKX3.1 expression showed a low sensitivity but a high specificity in our analysis. Methylome profiling on the other hand represents a sensitive, specific and reliable tool to support the diagnosis of MCS, particularly if only the round cell component is obtained in a biopsy and the diagnosis is not suspected. Furthermore, it can aid in confirming the diagnosis in case RNA sequencing for the HEY1::NCOA2 fusion transcript is not available.

Bioinspired collagen-gelatin-hyaluronic acid-chondroitin sulfate tetra-copolymer scaffold biomimicking native cartilage extracellular matrix facilitates chondrogenesis of human synovium-derived stem cells

The microenvironment plays a crucial role in stem cell differentiation, and a scaffold that mimics native cartilaginous extracellular components can promote chondrogenesis. In this study, a collagen–gelatin–hyaluronic acid–chondroitin sulfate tetra-copolymer scaffold with composition and architecture similar to those of hyaline cartilage was fabricated using a microfluidic technique and compared with a pure gelatin scaffold. The newly designed biomimetic scaffold had a swelling ratio of 1278 % ± 270 %, a porosity of 77.68 % ± 11.70 %, a compressive strength of 1005 ± 174 KPa, and showed a good resilience against compression force. Synovium-derived stem cells (SDSCs) seeded into the tetra-copolymer scaffold attached to the scaffold firmly and exhibited good mitochondrial activity, high cell survival with a pronounced glycosaminoglycan production. SDSCs cultured on the tetra-copolymer scaffold with chondrogenic induction exhibited upregulated mRNA expression of COL2A1, ChM-1, Nrf2, TGF-β1, and BMP-7. Ex vivo study revealed that the SDSC–tetra-copolymer scaffold regenerated cartilage-like tissue in SCID mice with abundant type II collagen and S-100 production. BMP7 and COL2A1 expression in the tetra-copolymer scaffold group was much higher than that in the gelatin scaffold group ex vivo. The tetra-copolymer scaffold thus exhibits strong chondrogenic capability and will facilitate cartilage tissue engineering.

Nasal Sesamoid Cartilages: Fact or Fiction? An Anatomical Study of the Lateral Nasal Ala.

To evaluate the presence of cartilage in the lateral nasal ala (LNA) via histological analysis of alar Mohs surgical specimens. An accurate understanding of nasal anatomy is essential to optimize esthetic and reconstructive surgical outcomes. LNA anatomy is typically pictured to include discreet accessory and sesamoid cartilages; however, the authors debate the actual presence of these structures. A blinded reviewer analyzed 101 lateral nasal alar histologic specimens from 362 tissue blocks using a Hematoxylin and Eosin (H&E) stain to assess for the presence of cartilage. Out of the 362 tissue blocks histologically analyzed, only 1 included cartilaginous components. We conclude that the presence of sesamoid and accessory cartilages in the LNA within our sample set is exceedingly rare.

Prognostic Significance of Percentage and Size of Dedifferentiation in Dedifferentiated Chondrosarcoma

Dedifferentiated chondrosarcoma is rare, aggressive, and microscopically bimorphic. How pathologic features such as the amounts of dedifferentiation affect prognosis remains unclear. We evaluated the percentages and sizes of dedifferentiation in a consecutive institutional series of dedifferentiated chondrosarcomas from 1999 to 2021. The statistical analysis included cox proportional hazard models and log-rank tests. Of the 67 patients (26 women, 41 men; age, 39 to >89 [median 61] years; 2 with Ollier disease), 58 presented de novo; 9 were identified with conventional chondrosarcomas 0.6–13.2 years (median, 5.5 years) prior. Pathologic fracture and distant metastases were noted in 27 and 7 patients at presentation. The tumors involved the femur (n = 27), pelvis (n = 22), humerus (n = 7), tibia (n = 4), scapula/ribs (n = 4), spine (n = 2), and clivus (n = 1). In the 56 resections, the tumors ranged in size from 3.5 to 46.0 cm (median, 11.5 cm) and contained 1%-99.5% (median, 70%) dedifferentiated components that ranged in size from 0.6 to 24.0 cm (median, 7.3 cm). No correlation was noted between total size and percentage of dedifferentiation. The dedifferentiated components were typically fibrosarcomatous or osteosarcomatous, whereas the associated cartilaginous components were predominantly grade 1-2, rarely enchondromas or grade 3. The entire cohort's median overall survival and progression-free survival were 11.8 and 5.4 months, respectively. In the resected cohort, although the total size was not prognostic, the percentage of dedifferentiation ≥20% and size of dedifferentiation >3.0 cm each predicted worse overall survival (9.9 vs 72.5 months; HR, 3.76; 95% CI, 1.27-11.14; P = .02; 8.7 vs 58.9 months; HR, 3.03; 95% CI, 1.21-7.57; P = .02, respectively) and progression-free survival (5.3 vs 62.1 months; HR, 3.05; 95% CI, 1.13-8.28; P = .03; 5.3 vs 56.6 months; HR, 2.50; 95% CI, 1.06-5.88; P = .04, respectively). In conclusion, both the percentages and sizes of dedifferentiation were better prognostic predictors than total tumor sizes in dedifferentiated chondrosarcomas, highlighting the utility of their pathologic evaluations.

Resection of a rare giant chondromesenchymal hamartoma of the scalp with intracranial blood supply in an adult woman: illustrative case.

Nasal chondromesenchymal hamartomas (NCMHs) are benign, slow-growing lesions formed by mesenchymal and cartilaginous components. They occur predominantly in male infants at the nasopharynx and orbit. Rare cases have been reported in adults. Ectopic NCMHs occurring in other head regions without the typical nasopharyngeal or orbital involvement have not been previously described. The authors presented the case of a 40-year-old woman with a giant mass in the left frontoparietal region that started to enlarge progressively after the patient's first pregnancy at the age of 21 years. The tumor caused intense headaches, nausea, vomiting, asthenia, and syncope. On admission, the neurological examination revealed no abnormalities. Brain magnetic resonance imaging showed a solid homogeneous tumor without intraaxial involvement extending inferiorly to the left zygomatic arch, with a significant mass effect on the adjacent bones but no infiltration. Remarkably, digital subtraction angiography demonstrated that the tumor received blood supply from superficial as well as intracranial branches of the left vertebral artery. After tumor resection, histopathological analysis revealed characteristics indistinguishable from an NCMH. The authors described a rare NCMH of the scalp with intracranial blood supply in an adult patient. A case with similar characteristics had not been reported before.

Mesenchymal chondrosarcoma of the head and neck with HEY1::NCOA2 fusion: A clinicopathologic and molecular study of 13 cases with emphasis on diagnostic pitfalls.

Mesenchymal chondrosarcoma (MCS) is a rare translocation-associated sarcoma, driven by a canonical HEY1::NCOA2 fusion. The tumors typically have a biphasic phenotype of primitive small blue round cells intermixed with hyaline cartilage. The head and neck (HN) region is a common site for MCS, accounting for 12-45% of all cases reported. We assembled a relatively large cohort of 13 molecularly confirmed HN MCS for a detailed clinicopathologic analysis. The underlying fusion events were determined using fluorescence in situ hybridization and/or targeted RNA sequencing. The median age of presentation was 19 years. Five MCSs (39%) had an intraosseous presentation (skull, maxilla, palate, and mandible), while the remaining eight cases occurred in the brain/meninges, orbit, and nasal cavity. Microscopically, HN MCSs were characterized by primitive round cells arranged in a distinctive nested architecture and a rich staghorn vasculature. A cartilaginous component of hyaline cartilage islands and/or single chondrocytes were present in 69% cases. A combined immunoprofile of CD99(+)/SATB2(+)/CD34(-)/STAT6(-) was typically noted. As this immunoprofile is non-specific, the referral diagnoses in cases lacking a cartilaginous component included Ewing sarcoma family and osteosarcoma. Among the seven patients with follow-up data, three developed distant metastasis and one died of disease. HN MCS may arise at intra- or extra-osseous sites. The HN MCS appears to have a more prolonged survival compared other MCS sites. Testing for HEY1::NCOA2 fusion is recommended in HN tumors with nested round cell morphology and staghorn vasculature that lack a distinctive cartilaginous component.

The skeleton of the giant Jacob Lolly is a unique “brand” of the department of normal anatomy

The paper presents the history of the appearance of the legendary skeleton of the giant Jacob Lolli in the museum collection of the Department of Normal Anatomy of the Military medical Academy. Research has been conducted on archival documents, including old magazines, newspapers, monographs, and minutes of the Academy Conference meetings stored in the Russian National Library, as well as the catalog and card index of the fundamental museum of the department. Data at the time of making the giant skeleton given in the catalog of the fundamental museum and literary sources of the 19th century were quite different and refer to the period from 1814 to 1818. Probably, the giants corpse was taken to the Department of Anatomy and Physiology of the Imperial MedicalSurgical Academy to establish the cause of death. After a while, the skeleton was presented to the Academy Conference as a rare museum exhibit and presented to its president, Jacov Willie, who returned the skeleton to the department. From 1818 to 1824, the skeleton temporarily left the walls of the academy and was examined by I.V. Buyalsky in the home museum. After the scientific work, the skeleton was returned to the department; as a result of the research conducted by I.V. Buyalsky in 1847, the article Measure of the skeleton and the weight of the bones of the giant Jacob Lolly, was the only published scientific work on the skeleton of a giant. The measurements were translated into the modern system of units. A brief description of the giants skull as a vivid example of typical changes in acromegaly was made a hundred years later by A.P. Bystrov, an employee of the department, in the book, Past, present, future of man. Two hundred years after its construction, the giants skeleton needed restoration, including delicate cleaning, restoration of destroyed fragments, and replacement of the material to imitate the cartilaginous components of the skeleton. The restorers work process is described, and the result of their activity is presented.

Intraspinal periosteal chondroma in upper thoracic spine causing cord compression and myelopathy: A case report.

IntroductionChondromas are slow-growing cartilage-forming benign tumors, rarely occurring in the spine. Generally, most spinal chondromas are asymptomatic; however, with slow progressive growth, these lesions may enlarge and expand and cause compressive neurological symptoms, resulting in radiculopathy or more commonly myelopathy due to direct neural compression.Presentation of caseA 15-year-old male adolescent presented to Emergency Department with history of fall (slippage) on concrete ground while playing three months back. On neurological examination, the motor power in bilateral upper limbs was 5/5 while it was 1/5 in both lower extremities. Some muscle wasting was noted in the lower limbs. The planter reflexes were upgoing; and the sensory loss was below T6 spinal level. CT scan of dorsolumbar spine demonstrated a well-defined high-density lesion in lateral aspect of spinal canal at T2-T3 vertebral level adjacent to left T2-T3 facet joint. MRI of dorsal spine revealed a 3 × 2 × 1 cm3-sized, well-defined, non-enhancing T1 low to isointense and T2/STIR heterogeneous hyperintense lesion with osseous and cartilaginous components in the left lateral aspect of spinal canal at T1-T3 level, causing compression and contralateral displacement of spinal cord. The patient was then subjected to posterior laminectomy, complete excision, followed by laminoplasty using minicranial plates and screws. Histopathology of the mass showed bony trabeculae with hematopoietic elements and attached lobules of hyaline cartilage, chondroid matrix and lobules of mature chondrocyte and myxoid changes. Postoperatively his power was improved slightly and he was able to stand up with some assistance. On six-month follow up, patient showed significant neurological improvement. He was able to walk independently with minimal assistance. He was able to control bowel and bladder functions.DiscussionChondromas occurring in the spine are rare, accounting for only about 3% of all chondromas. Spinal chondromas are commonly encountered in the thoracic spine as in our case.ConclusionComplete en bloc surgical excision is generally recommended as the treatment of choice for cases with local and/or neurological symptoms.

Anatomy of the Intermetatarsal Facets of the Fourth and Fifth Metatarsals

Category:Basic Sciences/BiologicsIntroduction/Purpose:The intermetatarsal joint between the fourth and fifth metatarsals (4-5 IM) is important in defining fifth metatarsal fractures. The purpose of the current study was to quantify this joint in order to determine the mean cartilage area, the percentage of the articulation that is cartilage, and to give the clinician data to help understand the joint anatomy as it relates to fifth metatarsal fracture classification.Methods:Twenty cadaver 4-5 IM joints were dissected. Digital images were taken and the articular cartilage was quantified by calibrated digital imaging software.Results:For the lateral fourth proximal intermetatarsal articulation, the mean area of articulation was 188 + 49 mm, with 49% of the area composed of articular cartilage. The shape of the articular cartilage had 3 variations: triangular, oval, and square. A triangular variant was the most common (80%, 16 of 20 specimens). For the medial fifth proximal intermetatarsal articulation, the mean area of articulation was 143 + 30 mm, with 48% of the joint surface being composed of articular cartilage. The shape of the articular surface was oval or triangular. An oval variant was the most common (75%, 15 of 20 specimens).Conclusion:This study supports the notion that the 4-5 IM joint is not completely articular and has both fibrous and cartilaginous components.

Concordance between Radiological Features and Histopathological Diagnosis of Cartilaginous Lesions of Bone among Patients at a Tertiary Care Centre, Trivandrum, Kerala

Introduction: Cartilaginous tumours comprise a large, heterogeneous group of mesenchymal neoplasms. They pose a challenge in terms of accurate diagnosis and management. Histopathological findings have direct implications for treatment outcomes. Aim: To determine the concordance between the radiological features and the histopathological diagnosis of cartilaginous lesions of bone. Materials and Methods: This was a retrospective study conducted in the Department of Pathology, Regional Cancer Centre, Trivandrum, Kerala, India, among 109 patients with histopathologically proven benign and malignant cartilaginous tumours, received in the laboratory between January 2012 and December 2021 for a duration of 10 years, were analysed. The study was conducted between September 2019 and January 2022. The demographic data for the study, including age, tumour site, clinical findings, and radiological diagnosis, were obtained from medical records. The cases were histopathologically graded based on the World Health Organization 2020 classification of tumours of soft tissue and bone. The concordance between histopathological diagnosis and radiological features was assessed. The Chi-square test was used to find the association between two categorical variables, and the Independent sample t-test was used to find the difference between two groups with respect to mean and standard deviation. Results: There were a total of 109 cases of cartilaginous tumours, out of which 82 cases (75.22%) were diagnosed as malignant and 27 cases (24.77%) were diagnosed as benign. Among benign neoplasms, chondroblastoma and osteochondroma were the most common, with 10 cases (37.03%) each. Among malignant chondroid tumours, 73 (89.02%) were diagnosed as conventional chondrosarcoma. There were five cases (6.09%) of secondary chondrosarcomas (malignant transformation of a benign cartilaginous lesion). Among the secondary chondrosarcomas, three cases (60%) were malignant transformation in osteochondroma, 1 (20%) in enchondroma, and 1 (20%) in synovial chondromatosis. Among the 91 cases for which radiology was available, 86 (94.50%) had a concordance between radiological and histopathological diagnosis. Five cases (5.49%) had a discordant radiological diagnosis. Conclusion: For histologically benign tumours, the radiological findings in the study were identical and concordant. For histologically malignant tumours, there were discrepancies with radiological findings in this study when the lesion had an associated cyst, absence of cortical destruction, or absence of a clear cartilaginous component and extra cortical expansion. For histologically suspicious cases in the study, the final diagnosis was made based upon radiological findings, with a particular interest in cortical destruction.

Histological examination of cranial synchondroses as functionally significant elements in the cranial osteopathic concept

Introduction. In recent decades, medical science has accumulated convincing evidence of the fact that the normal activity of a human brain depends on the functional integration of its vascular system, a circulation system of cerebrospinal fluid and biomechanical features of a skull, forming a single structural and functional system.The aim of the study is to research the histological structure of functionally significant cranial synchondroses in the middle and elderly age group, to find possible points of osteopathic influence application in their structure. Materials and methods. The study was performed on cadaver material of 27 persons (7 men — 26 %, 20 women — 74 %) who died at the age from 49 to 66 years (57,5±5,3 years) from various somatic pathologies, but had no history of craniocerebral injuries with fractures of osseous structures. Small bone fragments with sutures of interest/synchondroses (spheno-occipital synchondrosis, petro-jugular synchondrosis, sphenopetrosal synchondrosis) were subjected to standard histological processing followed by microscopy.Results. Evaluating histological specimens of spheno-occipital synchondrosis, we observed the similar pattern: highly mineralized tissues at the edges of the bodies of the sphenoid and occipital bones were connected without elements of cartilagi-nous or connective tissue. In all cases, no fibrous or nerve tissue elements were found during the in situ immunohistochemical reactions. Reactions with the CD34 antibody mark multiple vessels of the Volkmann's or Haversian canals. Evaluating histological specimens of petro-jugular and sphenopetrosal synchondroses, we found the presence of cartilage tissue in the suture in the form of small islands of various sizes (from 20 to 120 microns) with signs of degeneration and a small number of remained chondrocytes. When evaluating specimens with immunohistochemical reactions with antibodies against the S100 protein, no elements of the nervous tissue were detected.Conclusion. Spheno-occipital synchondrosis has a temporary nature. With age, its cartilaginous tissue is replaced by osseous one. According to the histological structure, sphenobasilar synchondrosis demonstrates the complete absence of a cartilaginous component in the middle and elderly age groups. Petro-jugular and sphenopetrosal synchondroses retain the cartilaginous component in their suture throughout lifetime. During histological examination of the petro-jugular and sphenopetrosal synchondroses, the cartilaginous component is represented by variety of small islands. In all synchondroses, there is an absence of vascular and nervous components. At the same time, we revealed the presence of a prominent vascular bed in the bone tissue. The fact requires emphasizing the importance of liquid potency and elastic component in cartilaginous and osseous tissues as an application point for osteopathic techniques.

Morphometric characteristics of the mucous membrane and the cartilaginous component of the larynx are normal at different times during the experimental opioid effect and during withdrawal

Background. The problem of uncontrolled use of opioid drugs is extremely relevant based on the data of domestic and world statistics which are covered in the scientific literature. That is why the study of indicators of morphometric characteristics of the laryngeal mucosa under opioid exposure under experimental opioid exposure will be of interest to both morphologists and practical otorhinolaryngologists. Objective: To study the morphometric parameters of the laryngeal mucosa in normal at different times of the experimental opioid effect and its cancellation. Methods. The material of the study were sexually mature, outbred rats - males in the amount of 61 animals, weighing 80 - 135 g, aged 4.5 - 7.5 months. Histological specimens were prepared according to conventional methods. All morphometric studies were performed using primary (unedited) photographs taken on a Meiji MT4300 LE microscope, Canon EOS 550D x100 lens. All statistical calculations were performed using RStudio v. 1.2.5042. Results. Throughout the experiment, the change of morphometric parameters of the laryngeal mucosa with signs of wavy growth and decline was clearly observed at all times. More positive was the dynamics of morphometric parameters after the abolition of the opioid analgesic, which hypothetically suggests the process of recovery of the mucosa, even after prolonged administration of the opioid.

Self-assembling human skeletal organoids for disease modeling and drug testing.

Skeletal conditions represent a considerable challenge to health systems globally. Barriers to effective therapeutic development include a lack of accurate preclinical tissue and disease models. Most recently, work was attempted to present a novel whole organ approach to modeling human bone and cartilage tissues. These self-assembling skeletal organoids mimic the cellular milieu and extracellular organization present in native tissues. Bone organoids demonstrated osteogenesis and micro vessel formation, and cartilage organoids showed evidence of cartilage development and maturation. Skeletal organoids derived from both bone and cartilage tissues yielded spontaneous polarization of their cartilaginous and bone components. Using these hybrid skeletal organoids, we successfully generated "mini joint" cultures, which we used to model inflammatory disease and test Adenosine (A2A ) receptor agonists as a therapeutic agent. The work and respective results indicated that skeletal organoids can be an effective biological model for tissue development and disease as well as to test therapeutic agents.