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International Journal of Computer... Feb 2020Predicting changes in face shape from corrective surgery is challenging in growing children with syndromic craniosynostosis. A prediction tool mimicking composite bone...
PURPOSE
Predicting changes in face shape from corrective surgery is challenging in growing children with syndromic craniosynostosis. A prediction tool mimicking composite bone and skin movement during facial distraction would be useful for surgical audit and planning. To model surgery, we used a radial basis function (RBF) that is smooth and continuous throughout space whilst corresponding to measured distraction at landmarks. Our aim is to showcase the pipeline for a novel landmark-based, RBF-driven simulation for facial distraction surgery in children.
METHODS
An individual's dataset comprised of manually placed skin and bone landmarks on operated and unoperated regions. Surgical warps were produced for 'older' monobloc, 'older' bipartition and 'younger' bipartition groups by applying a weighted least-squares RBF fitted to the average landmarks and change vectors. A 'normalisation' warp, from fitting an RBF to craniometric landmark differences from the average, was applied to each dataset before the surgical warp. The normalisation was finally reversed to obtain the individual prediction. Predictions were compared to actual post-operative outcomes.
RESULTS
The averaged change vectors for all groups showed skin and bone movements characteristic of the operations. Normalisation for shape-size removed individual asymmetry, size and proportion differences but retained typical pre-operative shape features. The surgical warps removed the average syndromic features. Reversing the normalisation reintroduced the individual's variation into the prediction. The mid-facial regions were well predicted for all groups. Forehead and brow regions were less well predicted.
CONCLUSIONS
Our novel, landmark-based, weighted RBF can predict the outcome for facial distraction in younger and older children with a variety of head and face shapes. It can replicate the surgical reality of composite bone and skin movement jointly in one model. The potential applications include audit of existing patient outcomes, and predicting outcome for new patients to aid surgical planning.
Topics: Cephalometry; Child; Craniofacial Dysostosis; Craniosynostoses; Face; Female; Humans; Male; Osteogenesis, Distraction; Postoperative Period; Plastic Surgery Procedures
PubMed: 31673962
DOI: 10.1007/s11548-019-02063-4 -
The Kobe Journal of Medical Sciences 2007This study has been performed to demonstrate the type and frequency of the anatomical variations of the sacroiliac joint according to age, gender, Body Mass Index and... (Comparative Study)
Comparative Study
This study has been performed to demonstrate the type and frequency of the anatomical variations of the sacroiliac joint according to age, gender, Body Mass Index and childbirth, and the influence of the anatomical variants to the uniformity and width of the joint space. It was conducted on 400 consecutive patients without sacroiliac complaint who underwent pelvic CT scanning for various reasons. Patients' ages were 15 or above. Anatomical variants that we observed were accessory sacroiliac joint (70 patients, 17.5%), iliosacral complex (38 patients, 9.5%), bipartite iliac bony plate (22 patients, 5.5%), semicircular defects on iliac/ sacral side (19 patients, 4.8%), crescent like iliac bony plate (14 patients, 3.5%) and ossification centers (4 patients, 1.0%). The mean joint space width of the 400 patients was 1.72+/-0.57 mm (from 0.77 mm to 4.39 mm). In adults below 40 years of age, the measured width was 2.49+/-0.66 mm. In older patients, 1.47+/-0.21 mm. Joints which presented anatomical variants (206 articulations) had a non-uniform joint space in 164 (79.6%), whereas uniform joint space were seen in 42 (20.4%) articulations. The joint width were less than 2 mm in 193 (93.7%) articulations and in 13 (6.3%) articulations were greater or equal to 2 mm. This study has demonstrated that anatomical variations and joint space are independently related to age, gender, Body Mass Index and childbirth in patients. We believe that all this information is helpful to interpret and examine the sacroiliac computed tomography images.
Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Body Mass Index; Female; Humans; Ilium; Male; Middle Aged; Obesity; Sacroiliac Joint; Sacrum; Sex Factors; Tomography, X-Ray Computed
PubMed: 18204297
DOI: No ID Found -
Scientific Reports Oct 2018The vascular wall within adipose tissue is a source of mesenchymal progenitors, referred to as perivascular stem/stromal cells (PSC). PSC are isolated via fluorescence...
The vascular wall within adipose tissue is a source of mesenchymal progenitors, referred to as perivascular stem/stromal cells (PSC). PSC are isolated via fluorescence activated cell sorting (FACS), and defined as a bipartite population of pericytes and adventitial progenitor cells (APCs). Those factors that promote the differentiation of PSC into bone or fat cell types are not well understood. Here, we observed high expression of WISP-1 among human PSC in vivo, after purification, and upon transplantation in a bone defect. Next, modulation of WISP-1 expression was performed, using WISP-1 overexpression, WISP-1 protein, or WISP-1 siRNA. Results demonstrated that WISP-1 is expressed in the perivascular niche, and high expression is maintained after purification of PSC, and upon transplantation in a bone microenvironment. In vitro studies demonstrate that WISP-1 has pro-osteogenic/anti-adipocytic effects in human PSC, and that regulation of BMP signaling activity may underlie these effects. In summary, our results demonstrate the importance of the matricellular protein WISP-1 in regulation of the differentiation of human stem cell types within the perivascular niche. WISP-1 signaling upregulation may be of future benefit in cell therapy mediated bone tissue engineering, for the healing of bone defects or other orthopaedic applications.
Topics: Adipose Tissue; Bone and Bones; CCN Intercellular Signaling Proteins; Cell Differentiation; Cell Separation; Cells, Cultured; Cellular Microenvironment; Fats; Flow Cytometry; Humans; Osteogenesis; Pericytes; Proto-Oncogene Proteins; Stem Cells; Tissue Engineering; Up-Regulation
PubMed: 30353078
DOI: 10.1038/s41598-018-34143-x -
Stem Cells Translational Medicine Oct 2014Adipose tissue is an attractive source of mesenchymal stem cells (MSCs) because of its abundance and accessibility. We have previously defined a population of native...
Adipose tissue is an attractive source of mesenchymal stem cells (MSCs) because of its abundance and accessibility. We have previously defined a population of native MSCs termed perivascular stem cells (PSCs), purified from diverse human tissues, including adipose tissue. Human PSCs (hPSCs) are a bipartite cell population composed of pericytes (CD146+CD34-CD45-) and adventitial cells (CD146-CD34+CD45-), isolated by fluorescence-activated cell sorting and with properties identical to those of culture identified MSCs. Our previous studies showed that hPSCs exhibit improved bone formation compared with a sample-matched unpurified population (termed stromal vascular fraction); however, it is not known whether hPSCs would be efficacious in a spinal fusion model. To investigate, we evaluated the osteogenic potential of freshly sorted hPSCs without culture expansion and differentiation in a rat model of posterolateral lumbar spinal fusion. We compared increasing dosages of implanted hPSCs to assess for dose-dependent efficacy. All hPSC treatment groups induced successful spinal fusion, assessed by manual palpation and microcomputed tomography. Computerized biomechanical simulation (finite element analysis) further demonstrated bone fusion with hPSC treatment. Histological analyses showed robust endochondral ossification in hPSC-treated samples. Finally, we confirmed that implanted hPSCs indeed differentiated into osteoblasts and osteocytes; however, the majority of the new bone formation was of host origin. These results suggest that implanted hPSCs positively regulate bone formation via direct and paracrine mechanisms. In summary, hPSCs are a readily available MSC population that effectively forms bone without requirements for culture or predifferentiation. Thus, hPSC-based products show promise for future efforts in clinical bone regeneration and repair.
Topics: Animals; Bone Transplantation; Cell Differentiation; Disease Models, Animal; Finite Element Analysis; Heterografts; Humans; Immunohistochemistry; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Osteogenesis; Rats; Spinal Fusion; X-Ray Microtomography
PubMed: 25154782
DOI: 10.5966/sctm.2014-0027 -
The Open Orthopaedics Journal 2017The patella is the largest sesamoid bone in the body and may have one (77%) or multiple (23%) ossification centres. Patellar and patellofemoral joint abnormalities are a...
INTRODUCTION
The patella is the largest sesamoid bone in the body and may have one (77%) or multiple (23%) ossification centres. Patellar and patellofemoral joint abnormalities are a common cause of anterior knee pain but symptomatic bipartite patella is an uncommon problem.
CASE SERIES
We report a series of six cases of painful synchondrosis in bipartite patellae, all in keen athletes following a direct blow to the anterior aspect of the knee. A complete rupture of the synchondrosis with evidence of retropatellar chondral separation was seen on MRI scan in all cases. Successful surgical fixation was undertaken with complete resolution of symptoms in all patients at an average of three months post-operatively.
CONCLUSION
Painful synchondrosis of a bipartite patella in young and active individuals following direct trauma is a relatively rare cause of anterior knee pain, but may be associated with significant morbidity. In cases refractory to non-operative management, successful symptomatic treatment can be achieved by operative fixation.
PubMed: 28603570
DOI: 10.2174/1874325001711010390 -
BMC Veterinary Research Apr 2016Navicular bone partition is a rare condition reported in horses, which is during the evaluation of a lameness or prepurchase examination often misinterpreted for a...
BACKGROUND
Navicular bone partition is a rare condition reported in horses, which is during the evaluation of a lameness or prepurchase examination often misinterpreted for a parasagittal fracture. In this report, the clinicopathological findings of three cases of navicular bone partition are evaluated. The possible pathomechanisms underlying the condition are hypothesised, focusing on a potential origin of foetal vascular disturbance. This study is furthermore aiming at a clearer and earlier recognition of navicular bone partition, since this condition would finally predispose for a clinical lameness with a poor prognosis.
CASE PRESENTATIONS
Case 1 was a 10-year-old Belgian Warmblood gelding with a Grade 3/5 chronic, recurrent left-forelimb lameness that had persisted for 4 months. Perineural palmar digital nerve block of the distal foot abolished the lameness. Radiographic examination revealed a bipartite navicular bone in the left forelimb. Unfortunately, the animal was lost to follow-up. Case 2 was a 7-year-old Quarter Horse stallion with a Grade 3/5 recurrent right forelimb lameness that had persisted for 2 years. The lameness switched to the contralateral left forelimb with a palmar digital nerve block. Radiographic examination identified a tripartite navicular bone in both forelimbs. Pathological examination additionally revealed chronic degenerative changes of the cartilage and subchondral bone with marked cystic changes. Case 3 was a 5-year-old Dutch Warmblood gelding with a Grade 3/5 recurrent left hindlimb lameness that had persisted for 6 months. Owing to the uncooperative behaviour of the horse, only a combined peroneal and tibial nerve block could be performed, which abolished the lameness. Radiographic examination revealed a bipartite navicular bone in the left hindlimb. Pathological examination showed a navicular bipartition in the left hindlimb, with microscopic changes comparable to those evident in Case 2; additionally, cartilage indentations were also found in the navicular bones of the right front- and hindlimb at a similar location as the partition site in the left hindlimb.
CONCLUSIONS
It is speculated that a navicular bone partition has a congenital origin and is caused by vascular disturbance during foetal development. This may lead to aberrant endochondral ossification or the formation of multiple ossification centres resulting in navicular bone partitioning. In the adult horse, chronic repetitive biomechanical challenges at the partition sites may induce local degenerative changes with subchondral cyst formation and thus would cause a gradually developing chronic lameness with a poor prognosis.
Topics: Animals; Bone Diseases; Forelimb; Hindlimb; Horse Diseases; Horses; Lameness, Animal; Male; Radiography; Tarsal Bones
PubMed: 27061802
DOI: 10.1186/s12917-016-0698-4 -
Clinical Orthopaedics and Related... Oct 2008We report the case of a bilateral bipartite ossification center of the proximal tibia in a 15-year-old boy with a history of knee injury. The presence of the duplicated...
We report the case of a bilateral bipartite ossification center of the proximal tibia in a 15-year-old boy with a history of knee injury. The presence of the duplicated ossific centers was an incidental finding on radiography and computed tomography performed after injury. Arthroscopy showed continuous hyaline cartilage between the two ossific centers confirming the diagnosis of a developmental abnormality; however, the articular surface was depressed in the region overlying the smaller ossific center. We presume the presence of an accessory center in the posteromedial aspect of the tibial plate could be a source of instability for the corresponding capsular and meniscal structures. This is, to our knowledge, the first report of tibial bipartite epiphysis.
Topics: Adolescent; Arthroscopy; Epiphyses; Humans; Hyaline Cartilage; Incidental Findings; Joint Instability; Knee Injuries; Male; Ossification, Heterotopic; Tibia; Tomography, X-Ray Computed
PubMed: 18663548
DOI: 10.1007/s11999-008-0400-7 -
The Journal of Bone and Joint Surgery.... Jul 2010We describe five adolescent patients aged between 13 and 16 years with bipartite ossification of the posteromedial aspect of the talus. All presented without a history...
We describe five adolescent patients aged between 13 and 16 years with bipartite ossification of the posteromedial aspect of the talus. All presented without a history of trauma. All the ankles had a similar radiological appearance. Clinically, some restriction of movement was noted in three ankles and two subtalar joints, In addition, pain was noted over the posteromedial aspect of the ankle in three patients. In each patient the bipartite fragment was excised through a posteromedial approach to the ankle. Complete resolution was achieved at six months in three patients, with the remaining two describing exercise-induced symptoms. In one of these this precluded participation in sport. Despite numerous anatomical variations within the tarsus, a case series of a bipartite talus has not previously been reported. This anatomical variation should be recognised to avoid misinterpretation as post-traumatic or other pathological processes. In the presence of recalcitrant symptoms excision is an option, but this is not universally successful in abolishing symptoms.
Topics: Adolescent; Ankle Joint; Arthralgia; Female; Humans; Male; Ossification, Heterotopic; Range of Motion, Articular; Retrospective Studies; Talus
PubMed: 20595113
DOI: 10.1302/0301-620X.92B7.23465 -
Seminars in Plastic Surgery Nov 2014Midface hypoplasia or retrusion remains a persistent feature of syndromic craniosynostosis years after successful treatment of the cranium. Although expansion of the...
Midface hypoplasia or retrusion remains a persistent feature of syndromic craniosynostosis years after successful treatment of the cranium. Although expansion of the cranial vault in infancy by traditional fronto-orbital advancement, posterior expansion, or both, can treat the immediate intracranial constriction, midface hypoplasia and its stigmata of exorbitism, sleep apnea, central face concavity, and malocclusion remain suboptimally treated. Initial enthusiasm for the procedures was tempered due to a high rate of infectious complications; timing and indications for surgery continue to stir controversy. During the last decade renewed interest with the monobloc and facial bipartition procedure using distraction osteogenesis with either an internal or external distraction system has decreased morbidity significantly. These procedures have re-emerged as powerful and comprehensive tools in the treatment of syndromic midface hypoplasia.
PubMed: 26417208
DOI: 10.1055/s-0034-1390170 -
PloS One 2014The study of the holotype and of a new specimen of Nanchangosaurus suni (Reptilia; Diapsida; Hupehsuchia) revealed a suite of hitherto unrecognized characters. For...
The study of the holotype and of a new specimen of Nanchangosaurus suni (Reptilia; Diapsida; Hupehsuchia) revealed a suite of hitherto unrecognized characters. For example, Nanchangosaurus has bipartite neural spines and its vertebral count is nearly identical to that of Hupehsuchus. It differs from the latter in having poorly developed forelimbs despite the advanced ossification in the rest of the skeleton. Other differences all pertain to hupehsuchian plesiomorphies retained in Nanchangosaurus, such as low neural spines. The relationship of Hupehsuchia within Diapsida was analyzed based on a data matrix containing 41 taxa coded for 213 characters, of which 18 were identified as aquatic adaptations from functional inferences. These aquatic adaptations may be vulnerable to the argumentation of character homology because expectation for homoplasy is high. There is an apparent incongruence between phylogenetic signals from aquatic adaptations and the rest of the data, with aquatic adaptations favoring all marine reptiles but Helveticosaurus to form a super-clade. However, this super-clade does not obtain when aquatic adaptations were deleted, whereas individual marine reptile clades are all derived without them. We examined all possible combinations of the 18 aquatic adaptations (n = 262143) and found that four lineages of marine reptiles are recognized almost regardless of which of these features were included in the analysis: Hupehsuchia-Ichthyopterygia clade, Sauropterygia-Saurosphargidae clade, Thalattosauria, and Helveticosaurus. The interrelationships among these four depended on the combination of aquatic adaptations to be included, i.e., assumed to be homologous a priori by bypassing character argumentation. Hupehsuchia always appeared as the sister taxon of Ichthyopterygia.
Topics: Adaptation, Physiological; Animals; Aquatic Organisms; China; Fossils; Phylogeny; Reptiles; Spine
PubMed: 25014493
DOI: 10.1371/journal.pone.0102361