Raine syndrome: Prenatally identified severe craniofacial phenotype with multisuture synostosis and brain abnormalities associated with variants in FAM20C.

Raine syndrome (MIM 259775) is a rare autosomal recessive disorder, first described by Raine et al. in 1989, with an estimated prevalence of <1/1,000,000. This is due to pathogenic variants in FAM20C characterized by osteosclerosis, typical craniofacial features, and brain calcifications. Here, we report a novel variant in FAM20C, describe a uniquely severe craniofacial and CNS phenotype of Raine syndrome, and correlate it with prenatal findings. Fetal phenotyping was based on ultrasound and MRI. Solo exome sequencing was performed from DNA extracted from postmortem skin biopsy. Targeted parental variant testing was subsequently performed. A homozygous missense variant NM_020223.4 (c.1445 G > A (p.Gly482Glu)) was identified in FAM20C associated with Raine syndrome. The infant had the characteristic dysmorphic features seen in Raine syndrome. He had particularly significant CNS manifestations consisting of multisuture craniosynostosis with protrusion of the brain parenchyma through fontanelles and cranial lacunae. Histological sections of the brain showed marked periventricular gliosis with regions of infarction, hemorrhage, and cavitation with global periventricular leukomalacia. Numerous dystrophic calcifications were diffusely present. Here, we demonstrate the identification of a novel variant in FAM20C in an infant with the characteristic features seen in Raine syndrome. The patient expands the characteristic phenotype of Raine syndrome to include a uniquely severe CNS phenotype, first identified on prenatal imaging.

Impact of osteosclerosis on cervical pedicle screw insertion using preoperative CT-based navigation.

PURPOSE: Preoperative computed tomography (CT)-based navigation is used for cervical pedicle screw (CPS) insertion to mitigate the risk of spinal cord and vertebral artery injury. In vertebrae with osteosclerosis due to degeneration or other factors, however, probing may not proceed easily, with difficulty creating the CPS insertion hole. This study investigated the impact of osteosclerosis on the accuracy of CPS insertion. METHODS: A total of 138 patients with CPS inserted at the C3-C7 level using preoperative CT navigation were retrospectively analyzed. Pre- and postoperative CT was employed to investigate screw position and Hounsfield unit (HU) values at the lateral mass to evaluate the degree of osteosclerosis in the CPS insertion pathway. RESULTS: Among 561 CPS insertions, the Grade 3 perforation rate was 1.8%, and the Grade 2 or higher perforation rate was 8.0%. When comparing insertions with and without CPS perforation, HU values were significantly higher in the perforation group (578 ± 191 vs. 318 ± 191, p < 0.01). The frequency of CPS insertion into the mid-cervical spine was also significantly greater in the perforation group (68.9% vs. 62.5%, p < 0.01). Logistic regression analysis revealed that a high HU value at the lateral mass (odds ratio 1.09, 95% confidence interval: 1.07-1.11, p < 0.01) was a significant independent factor associated with CPS deviation. CONCLUSIONS: The screw perforation rate of Grade 2 or higher in CPS insertion using preoperative CT-based navigation was 8.0%. Since osteosclerosis was an independent factor related to CPS deviation, additional care may be required during insertion into affected vertebrae.

Novel mutation in LRP5 gene cause rare osteosclerosis: cases studies and literature review.

To study the effects of low-density lipoprotein receptor-related protein 5 (LRP5) gene mutations on bone, and to open up our view of LRP5 and Wnt pathways on bone mass regulation. Three patients with increased bone mineral density or thickened bone cortex were included, who were 30-year-old, 22-year-old and 50-year-old men, respectively. The latter two patients were son and father of a same family. The characteristics of bone X-rays were evaluated in detail. Bone turnover markers were detected, such as procollagen type 1 amino-terminal peptide (P1NP), alkaline phosphatase (ALP), and type 1 collagen carboxyl terminal peptide (ß-CTX). Dual energy X-ray absorptiometry (DXA) was used to measure the bone mineral density (BMD) at lumbar spine and proximal femur of the patients. The targeted next-generation sequencing (NGS) technology was used to detect pathogenic gene mutations, which were further verified by Sanger sequencing. Moreover, the gene mutation spectrum and phenotypic characteristics of reported patients with LRP5 gain-of-function mutations were summarized by reviewing the literature. The main characteristics of the first patient were headache, facial paralysis, high BMD (lumbar vertebrae 1-4: 1.877 g/cm2, Z-score: 5.8; total hip: 1.705 g/cm2, Z-score: 5.7), slightly increased P1NP (87.0 ng/mL) and ß-CTX (0.761 ng/mL) level, and with thickened bone cortex, especially the cranial vault. The latter two patients showed enlargement of the mandible and enlarged osseous prominence of the tours palatinus. X-rays showed that the bone cortex of skull and long bones were thickened. The bone turnover markers and BMD were normal. All three cases carried novel missense mutations in LRP5 gene, which were mutation in exon 3 (c.586 T > G, p.Trp196Gly) of the first patient, and mutation in exon 20 (c.4240C > A, p.Arg1414Ser) of the latter two patients. Combined with the reported literature, a total of 19 gain-of-function mutations in LRP5 were detected in 113 patients from 33 families. Hotspot mutations included c.724G > A, c.512G > T and c.758C > T. Furthermore, mutations in the exon 3 of LRP5 may cause severe phenotypes. LRP5 gain-of-function mutations can lead to rare autosomal dominant osteosclerosis type Ι (ADO Ι), which was characterized by increased bone mass and thickened bone cortex. In-depth research on the Wnt pathway will be benefit for discovering important mechanisms of bone mass regulation.

Neurological manifestations in patients and disease carriers in an Italian family with osteosclerosis.

BACKGROUND: Hereditary cranial hyperostosis is a rare disease never described in Italy, so the neurological manifestations in patients and carriers of the disease have been little studied. METHODS: We describe the neurological and neuroimaging features of patients and carriers of the gene from a large Italian family with sclerosteosis. RESULTS: In this family, genetic testing detected the homozygous p.Gln24X (c.70C > T) mutation of the SOST gene in the proband and a heterozygous mutation in 9 siblings. In homozygous adults, severe craniofacial hyperostosis was manifested by cranial neuropathy in childhood, chronic headache secondary to intracranial hypertension, and an obstructive sleep apnea syndrome in adults. In one of the adult patients, there was a compressible subcutaneous swelling in the occipital region caused by transosseous intracranial-extracranial occipital venous drainage, a compensation mechanism of obstructed venous drainage secondary to cranial hyperostosis. Mild cranial hyperostosis causing frequent headache and snoring was evident in the nine heterozygous subjects. CONCLUSIONS: Multiple cranial neuropathies and headache in children, while severe chronic headache and sleep disturbances in adults, are the neurological manifestations of the first Italian family with osteosclerosis. It is reasonable to extend neurological and neuroimaging evaluation to gene carriers as well.

Case 298: Skeletal Fluorosis Secondary to Huffing.

History A 37-year-old man from the United States presented with a 1-year history of neck pain and stiffness that had been unsuccessfully treated with manipulative therapy by a chiropractor at another institution. Past medical history was remarkable only for marijuana and air duster abuse. He denied use of any prescription medications. Physical examination was notable for markedly reduced range of motion of the cervical spine. Laboratory work-up revealed an elevated alkaline phosphatase level (302 U/L [5.0 µkat/L]; normal range, 40-100 U/L [0.7-1.67 µkat/L]), but all other laboratory findings, including complete blood count, renal function, liver function, vitamin A level, serum protein electrophoresis, and hepatitis C antibodies were within normal limits. Cervical spine radiography was performed, followed by MRI. Subsequently, a full skeletal survey was ordered. Included are representative radiographs of the pelvis, left forearm, and distal right leg with ankle.

A Deep Learning Model for Idiopathic Osteosclerosis Detection on Panoramic Radiographs.

OBJECTIVE: The purpose of the study was to create an artificial intelligence (AI) system for detecting idiopathic osteosclerosis (IO) on panoramic radiographs for automatic, routine, and simple evaluations. SUBJECT AND METHODS: In this study, a deep learning method was carried out with panoramic radiographs obtained from healthy patients. A total of 493 anonymized panoramic radiographs were used to develop the AI system (CranioCatch, Eskisehir, Turkey) for the detection of IOs. The panoramic radiographs were acquired from the radiology archives of the Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Eskisehir Osmangazi University. GoogLeNet Inception v2 model implemented with TensorFlow library was used for the detection of IOs. Confusion matrix was used to predict model achievements. RESULTS: Fifty IOs were detected accurately by the AI model from the 52 test images which had 57 IOs. The sensitivity, precision, and F-measure values were 0.88, 0.83, and 0.86, respectively. CONCLUSION: Deep learning-based AI algorithm has the potential to detect IOs accurately on panoramic radiographs. AI systems may reduce the workload of dentists in terms of diagnostic efforts.

Development and Validation of a Radiomics Model for Differentiating Bone Islands and Osteoblastic Bone Metastases at Abdominal CT.

Background It is important to diagnose sclerotic bone lesions in order to determine treatment strategy. Purpose To evaluate the diagnostic performance of a CT radiomics-based machine learning model for differentiating bone islands and osteoblastic bone metastases. Materials and Methods In this retrospective study, patients who underwent contrast-enhanced abdominal CT and were diagnosed with a bone island or osteoblastic metastasis between 2015 to 2019 at either of two different institutions were included: institution 1 for the training set and institution 2 for the external test set. Radiomics features were extracted. The random forest (RF) model was built using 10 selected features, and subsequent 10-fold cross-validation was performed. In the test phase, the RF model was tested with an external test set. Three radiologists reviewed the CT images for the test set. The sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (AUC) were calculated for the models and each of the three radiologists. The AUCs of the radiomics model and radiologists were compared. Results A total of 177 patients (89 with a bone island and 88 with metastasis; mean age, 66 years ± 12 [standard deviation]; 111 men) were in the training set, and 64 (23 with a bone island and 41 with metastasis; mean age, 69 years ± 14; 59 men) were in the test set. Radiomics features (n = 1218) were extracted. The average AUC of the RF model from 10-fold cross-validation was 0.89 (sensitivity, 85% [75 of 88 patients]; specificity, 82% [73 of 89 patients]; and accuracy, 84% [148 of 177 patients]). In the test set, the AUC of the trained RF model was 0.96 (sensitivity, 80% [33 of 41 patients]; specificity, 96% [22 of 23 patients]; and accuracy, 86% [55 of 64 patients]). The AUCs for the three readers were 0.95 (95% CI: 0.90, 1.00), 0.96 (95% CI: 0.90, 1.00), and 0.88 (95% CI: 0.80, 0.96). The AUC of radiomics model was higher than that of only reader 3 (0.96 vs 0.88, respectively; P = .03). Conclusion A CT radiomics-based random forest model was proven useful for differentiating bone islands from osteoblastic metastases and showed better diagnostic performance compared with an inexperienced radiologist. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Vannier in this issue.

Resolution of sclerotic lesions of dysosteosclerosis due to biallelic SLC29A3 variant in a Turkish girl.

Dysosteosclerosis is a group of sclerosing bone dysplasia characterized by short stature, increased bone fragility, osteosclerosis, and platyspondyly. It is a genetically heterogeneous disorder caused by biallelic mutations in the SLC29A3, TNFRSF11A, TCIRG1, and CSF1R genes. To date, four dysosteosclerosis patients with SLC29A3 mutations have been reported. Here, we report biallelic SLC29A3 (c.303_320dupCTACTTTGAGAGCTACCT) variant in a three-year-old girl. She had large anterior fontanelle, fracture history, short stature, camptodactyly, elbow contracture, and melanocytic nevus. Initial skeletal radiographs revealed platyspondyly, dense vertebral endplates (sandwich appearance of the vertebral bodies), diffuse sclerosis of the peripheral side of the pelvic bones, sclerosis of metaphysis and diaphysis of the long bones, metaphyseal widening, and diaphyseal cortical thickening. Mild sclerosis was also present in the skull base, maxilla, rib, scapula, and phalanges. Notably, we observed that sandwich vertebrae appearance significantly resolved and sclerosis of ribs, scapula, pelvis, and long bone metaphysis regressed over a 2.5-year period. However, platyspondyly, metaphyseal widening, and diaphyseal cortical thickening persisted. In conclusion, this study demonstrates spontaneous resolution of osteosclerosis, which was not described previously in patients with dysosteosclerosis.

Recurrent variant c.1680C>A in FAM20C gene and genotype-phenotype correlation in a patient with Raine syndrome: a case report.

BACKGROUND: Bi-allelic mutations in FAM20C gene are known to cause a rare genetic disorder- Raine syndrome (RS). The FAM20C protein binds calcium and phosphorylates proteins involved in biomineralization of bones and teeth. RS is recognized as an osteosclerotic bone dysplasia. It is characterized by distinctive facial features, generalized osteosclerosis and respiratory insufficiency along with periosteal bone formation. RS is typically described as being an aggressive skeletal dysplasia with death in the neonatal period or early infancy. However, in the recent past an increasing number of individuals having an extended life span along with a highly heterogeneous phenotype has led to classifying RS into short and extended lifespan categories. CASE PRESENTATION: We report a case of RS with antenatal fractures, facial dysmorphism and osteosclerosis without significant respiratory manifestations. The child has a relatively extended lifespan, whereby she died at 17-months of age. Clinical exome sequencing revealed a previously known, homozygous, nonsense variant c.1680C > A (p.Cys560Ter) in exon 10 of FAM20C. Whilst the variant was initially classified as a variant of uncertain significance (VUS), through the latest release of gnomAD and GTEx data, this was subsequently re-classified as likely pathogenic. Furthermore, segregation analysis showed both parents to be carriers. In contrast, a previously reported case with the same variant had polyhydramnios, complex facial abnormalities and bright echogenic brain parenchyma with oval shaped skull and anterior flattening at 26 weeks of gestation. CONCLUSION: The variant identified has been previously reported as a VUS. The present case provides further evidence towards the pathogenicity of the variant. A plausible genotype-phenotype correlation based on the location of the variant has been verified, wherein the position of a nonsense variant in the terminal exon of FAM20C gene, could have had a partial effect on the protein function, thereby resulting in a relatively milder phenotype and extended lifespan. Furthermore, the vast phenotypic variation on clinical comparison current case and a previously reported case, despite having the same genotype, could suggest an oligogenic effect and/ or environmental influence.

The imaging role for diagnosis of idiopathic osteosclerosis: a retrospective approach based on records of 33,550 cases.

OBJECTIVE: The study aimed to describe the diagnostic imaging features of idiopathic osteosclerosis (IO) to aid in differential diagnosis of similar dentomaxillomandibular conditions. MATERIALS AND METHODS: An archive of 550 dentomaxillofacial radiographic (panoramic radiography (PR) and cone beam computed tomography (CBCT)) images and 33,000 histopathological records were reviewed to identify IO cases. Chi-square, Student's t test, and ANOVA tests, with a significance of p < 0.05, were applied for comparative analysis. In addition, we analyzed various studies to present a short review. RESULTS: After meticulous observation, 36 images of 34 patients revealed 60 IO lesions in 31 PR and 5 CBCT. Sex, age group, anatomical site, shape, regularity, and root relationship showed statistical significance: sex and age group (p = 0.046), sex and IO regularity (p = 0.007), age group and IO regularity (p = 0.014), anatomical site and IO shape (p = 0.010), anatomical site and IO regularity (p = 0.003), and IO shape and IO regularity (p = 0.002). We presented a short review from 26 articles, including retrospective, cross-sectional, and longitudinal studies, documenting 2307 patients with 2435 IO lesions from 51,160 imagiological examinations. CONCLUSIONS: A radiographic diagnostic profile of IO may guide the clinical practitioners in differentiating an incidental radiopacity. PR is a preliminary examination, with CBCT facilitating the IO diagnosis. CLINICAL RELEVANCE: Knowledge of imaging characteristics variability of idiopathic osteosclerosis is crucial for accurate diagnosis process when incidental radiopacities are found in the panoramic radiographs, thus avoiding unnecessary biopsies. CBCT scans facilitate the interpretation of idiopathic osteosclerosis overlapping the mandibular canal.

Raine syndrome: Prenatal diagnosis based on recognizable fetal facial features and characteristic intracranial calcification.

OBJECTIVE: The purpose of this study was to elucidate the facial morphology and the pattern of internal malformations in three fetuses with RS born to first cousins of Egyptian decent. METHODS: The fetal ultrasonography findings were highly suggestive of RS leading to targeted Sanger sequencing of FAM20C and postnatal assessment. RESULTS: The prenatal ultrasound findings of osteosclerotic skull, exorbitism, hypoplastic nose, midface hypoplasia, small mouth with down-curved corners, and a distinct and recognizable pattern of intracranial calcification were identified in three fetuses with RS. The calcifications were evident specifically around the corpus callosum and/or ventricular walls. Ectopic renal and hepatic calcifications, pulmonary hypoplasia, mild rhizomelic shortening of the upper limbs, intrauterine fractures, and cerebellar hypoplasia were also noted. Molecular analysis identified three novel homozygous variants, two frameshift: [c.456delC (p.Gly153Alafs*34)] in exon 1 and [c.905delT (Phe302Serfs*35)] in exon 4 and one nonsense mutation in exon 10, [c.1557C>G(p.Tyrs519*)]. The three variants were segregated with the phenotype. This is the first description of a phenotype associated with homozygous truncating variants of FAM20C. CONCLUSION: RS has characteristic prenatal ultrasound findings which can improve the prenatal identification of this condition and help in guiding the molecular diagnosis and counseling.

Diagnosis and treatment of intramedullary osteosclerosis: a report of three cases and literature review.

BACKGROUND: Intramedullary osteosclerosis (IMOS) is a rare condition without specific radiological findings except for the osteosclerotic lesion and is not associated with family history and infection, trauma, or systemic illness. Although the diagnosis of IMOS is confirmed after excluding other osteosclerotic lesions, IMOS is not well known because of its rarity and no specific feature. Therefore, these situations might result in delayed diagnosis. Hence, this case report aimed to investigate three cases of IMOS and discuss imaging findings and clinical outcomes. CASE PRESENTATION: All three cases were examined between 2015 and 2019. The location of osteosclerotic lesions were femoral diaphyses in the 60-year-old man (Case 1) and 41-year-old woman (Case 2) and tibial diaphysis in the 44-year-old woman (Case 3). All cases complained of severe pain and showed massive diaphyseal osteosclerotic lesions in plain radiograms and computed tomography (CT) scans. Cases 2 and 3 were examined using the triphasic bone scan, and a fusiform-shaped intense area of the tracer uptake on delayed bone image was detected in both cases without (Case 2) or slightly increased vascularity (Case 3) on the blood pool image, which was reported as a specific finding of IMOS. Open biopsy was performed in all cases, and histologic section showed trabecular bone sclerosis with hypocellular fibrous tissues, finally diagnosed as IMOS. The pain was sharply improved after biopsy and kept at the latest follow-up periods (34, 33, and 6 months in Cases 1, 2, and 3, respectively). CONCLUSIONS: Massive sclerotic lesions with severe pain in the diaphyseal region of long bones should be considered as IMOS to avoid the delayed diagnosis, although other sclerotic bony lesions should be carefully excluded. Triphasic bone scan with a fusiform-shaped intense area of tracer uptake on delayed bone image and without or slightly increased vascularity on the blood pool image will help confirm IMOS. The role of open biopsy was to confirm the diagnosis of IMOS and to give the severe pain relief immediately in the three cases, although more cases and long-term follow-up are necessary.

Skeletal fluorosis: don't miss the diagnosis!

Skeletal fluorosis is a rare toxic osteopathy characterized by massive bone fixation of fluoride. The disease occurs as an endemic problem in some parts of the world and is the result of prolonged ingestion or rarely by inhalation of high amounts of fluoride. Radiographic presentation is mainly characterized by bone changes with osteocondensation and later ossification of many ligaments and interosseous membranes. Skeletal fluorosis is not clinically obvious and can be confused with other rheumatologic disorders. Its severity lies in the development of skeletal deformities and neurological complications. Management of fluorosis generally focuses on symptom treatment.

A novel FAM20C mutation causing hypophosphatemic osteomalacia with osteosclerosis (mild Raine syndrome) in an elderly man with spontaneous osteonecrosis of the knee.

Raine syndrome is characterized by FGF23-mediated hypophosphatemic osteomalacia with osteosclerosis caused by mutations in the FAM20C gene. We report a case of a 72-year-old man who presented with rapid progressive spontaneous osteonecrosis of the knee (SONK). A full osteologic assessment including dual energy X-ray absorptiometry (DXA), high-resolution peripheral quantitative computed tomography (HR-pQCT), and serum analyses revealed a high bone mass in the lumbar spine and hip (DXA T-score + 7.5 and + 4.7/+4.2) with increased bone microstructural parameters in the distal radius and tibia (BV/TV 127%, 140% of the age-matched mean, respectively), as well as a low bone turnover state. Phosphate levels were low due to renal phosphate wasting and high FGF23 levels (126.5 pg/ml, reference range 23.2-95.4 pg/ml). Using gene panel sequencing, we identified a novel FAM20C heterozygous missense mutation in combination with a homozygous duplication that potentially alters splicing. Taken together, this is the first case of mild Raine syndrome with spontaneous osteonecrosis of the knee, phosphate wasting, and a pronounced trabecular high bone mass phenotype.

Diffuse osteosclerosis as a presentation of recurrent breast cancer: role of endothelin 1.

We report a 46-yr-old woman with a history of breast cancer who presented with diffuse myalgias, bone pain, and osteosclerosis. She was found to have recurrent breast cancer producing endothelin-1. INTRODUCTION: Acquired osteosclerosis can be caused by various disorders. Endothelin -1 is believed to contribute to osteosclerosis caused by breast cancer. METHODS: Although the bone marrow biopsy did not reveal breast cancer, she developed skin lesions consistent with metastatic breast cancer. She ultimately died from progressive disease. At autopsy immunohistochemistry for endothelin-1 was performed on a section from the L5 vertebral body. RESULTS: The section from the L5 vertebral body showed small foci of cells consistent with metastatic carcinoma and a prominent sclerotic response. Immunohistochemistry for endothelin-1 was strongly positive. CONCLUSIONS: Recurrent breast cancer may present with diffuse osteosclerosis. Endothelin-1 may be a paracrine factor responsible for increased bone formation and osteosclerosis.

The effect of ultraviolet photofunctionalization of titanium instrumentation in lumbar fusion: a non-randomized controlled trial.

BACKGROUND: Titanium instrumentations are widely used in orthopedics; the metal bonds with bone in a process called osseointegration. Over time, hydrocarbons adhere to the instrumentation, which weakens the bone-binding ability. Ultraviolet photofunctionalization enhances the bone-binding ability of instrumentation by reducing hydrocarbons. The process has been proven effective in dentistry, but its effects in orthopedics are unverified. We aimed to determine the effect of ultraviolet photofunctionalization of titanium instrumentation used in lumbar fusion. METHODS: This was a non-randomized controlled trial. We prospectively enrolled 13 patients who underwent lumbar fusion surgery. We inserted two pure titanium cages into each intervertebral space; one cage had undergone ultraviolet photofunctionalization, while the other was untreated. The degree of osteosclerosis around both cages was then compared by measuring the densities around the cages on imaging at 2, 3, 6, and 12 months postoperatively compared with 1 month postoperatively. The carbon attachment of the titanium cages was measured using X-ray photoelectron spectroscopy. RESULTS: There was no significant difference between the degree of osteosclerosis (as assessed by the density) around the treated versus untreated cages at any timepoint. The ratio of carbon attachment of the titanium cages was only 20%, which was markedly less than the ratio of carbon attachment to titanium instrumentation previously reported in the dentistry field. CONCLUSIONS: The effect of ultraviolet photofunctionalization of titanium instrumentation in spine surgery is questionable at present. The biological aging of the titanium may be affected by differences in the manufacturing process of orthopedics instrumentation versus dentistry instrumentation. TRIAL REGISTRATION: UMIN Clinical Trials Registry (Identifier: UMIN000014103 ; retrospectively registered on June 1, 2014).

Finite-element analysis of the proximal tibial sclerotic bone and different alignment in total knee arthroplasty.

BACKGROUND: Despite potential for improving patient outcomes, studies using three-dimensional measurements to quantify proximal tibial sclerotic bone and its effects on prosthesis stability after total knee arthroplasty (TKA) are lacking. Therefore, this study aimed to determine: (1) the distribution range of tibial sclerotic bone in patients with severe genu varum using three-dimensional measurements, (2) the effect of the proximal tibial sclerotic bone thickness on prosthesis stability according to finite-element modelling of TKA with kinematic alignment (KA), mechanical alignment (MA), and 3° valgus alignment, and (3) the effect of short extension stem augment utilization on prosthesis stability. METHODS: The sclerotic bone in the medial tibial plateau of 116 patients with severe genu varum was measured and classified according to its position and thickness. Based on these cases, finite-element models were established to simulate 3 different tibial cut alignments with 4 different thicknesses of the sclerotic bone to measure the stress distribution of the tibia and tibial prosthesis, the relative micromotion beneath the stem, and the influence of the short extension stem on stability. RESULTS: The distribution range of proximal tibial sclerotic bone was at the anteromedial tibial plateau. The models were divided into four types according to the thickness of the sclerotic bone: 15 mm, 10 mm, 5 mm, and 0 mm. The relative micromotion under maximum stress was smallest after MA with no sclerotic bone (3241 µm) and largest after KA with 15 mm sclerotic bone (4467 µm). Relative micromotion was largest with KA and smallest with MA in sclerotic models with the same thickness. Relative micromotion increased as thickness of the sclerotic bone increased with KA and MA (R = 0.937, P = 0.03 and R = 0.756, P = 0.07, respectively). Relative micromotion decreased with short extension stem augment in the KA model when there was proximal tibial sclerotic bone. CONCLUSIONS: The influence of proximal tibial sclerotic bone on prosthesis's stability is significant, especially with KA tibial cut. Tibial component's short extension stem augment can improve stability.

Systemic Changes Affecting the Morphology of Calvarial Bone.

Plastic surgeons are frequently consulted to evaluate concerns about a patient's skull. Imaging studies often reveal abnormalities in bone morphology, from increased porosity to sclerotic changes. While focal findings imply a benign or malignant neoplasm, the etiology of more diffuse findings can be more varied, making the correct diagnosis challenging. The present review summarizes the differential diagnosis of osseous lesions of the calvarium that affect the bone and contribute to changes seen on imaging studies.

Idiopathic osteosclerosis in the maxillomandibular area.

OBJECTIVES: To test a more complete set of morphometric radiographic parameters to evaluate the idiopathic osteosclerosis (IO) lesions located in the maxillomandibular area and to know their features during routine radiographic evaluation. MATERIALS AND METHODS: Radiographs from patients attending the oral diagnosis clinic of our institution were reviewed. Evaluated parameters were gender and age of the patients, size, side, homogeneity, morphology, radiodensity, mineralization, borders, relation to roots, affected tooth or teeth and location of the analyzed lesions. RESULTS: Of the 6340 assessed patients, 354 (5.6%) harbored 362 lesions. IOs were more common during 2nd to 4th decades (mean age = 39 years). IO frequency rose from 1st to 3rd decades and then decreased. Size varied from 0.1 to 5.8 cm, and its frequency increased from 7 to 30 years age and then decreased too. The mandible and molar region were more commonly affected. Radiopaque image, radicular location, round shape, homogeneous core and well-defined boundaries were the more frequent IO features. CONCLUSIONS: Our method allows to analyze IO lesions with precise parameters. Analysis of the results does not support the previously suggested theories to explain their origin, and these figures suggest that the so-called IOs are developmental alterations of the bone.