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The effective and long-term treatment of cartilage defects is an unmet need among patients worldwide. In the past, several synthetic and natural biomaterials have been designed to support functional articular cartilage formation. However, they have mostly failed to enhance the terminal stage of chondrogenic differentiation, leading to scar tissue formation after the operation. Growth factors substantially regulate cartilage regeneration by acting on receptors to trigger intracellular signaling and cell recruitment for tissue regeneration. In this study, we investigated the effect of recombinant insulin-like growth factor 1 (rIGF-1), loaded in fibrin microbeads (FibIGF1), on cartilage regeneration. rIGF-1-loaded fibrin microbeads were injected into full-thickness cartilage defects in the knees of goats. The stability, integration, and quality of tissue repair were evaluated at 1 and 6 months by gross morphology, histology, and collagen type II staining. The in vivo results showed that compared to plain fibrin samples, particularly at 6 months, FibIGF1 improved the functional cartilage formation, confirmed through gross morphology, histology, and collagen type II immunostaining. FibIGF1 could be a promising candidate for cartilage repair in the clinic.
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Doenças das Cartilagens , Cartilagem Articular , Humanos , Animais , Colágeno Tipo II/metabolismo , Fibrina/metabolismo , Cabras , Cartilagem Articular/metabolismo , Doenças das Cartilagens/metabolismo , CondrócitosRESUMO
Background: Failure of open reduction of developmental hip dislocation is a serious complication and revision surgery appear to be technically demanding with high complication rates. Little attention has been given in literature to patients in whom open reduction of developmental hip dislocation has failed. We present a systematic review about current perspectives and timing when to perform surgical revision after failed open reduction of developmental hip dislocation in children. Methods: Following the recommendations of the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" (PRISMA) statements we performed a comprehensive search of the PubMed and Google Scholar bibliographic database in order to select all studies published between 1980 and 2022. Studies were screened for the reasons for failure of open reduction, timing when revision surgery was performed, and for the surgical techniques used for revision. Results: A total of 10 articles including 252 patients and 268 hips has been recorded. The most common causes of re-dislocation after open reduction are inadequate exposure and failure to release the obstructing soft tissues inside and around the hip. In 90% of the cases the anterolateral approach was performed for revision surgery. Avascular necrosis occurred in 5%-67% of cases and was the most encountered complication. Conclusion: Redislocation of developmental hip dislocation after an open reduction has poor long-term outcomes mainly due to a high rate of avascular necrosis of the femoral head. It is mandatory to obtain a stable reduction at the second surgery combining soft tissue release, capsulorrhaphy, pelvic and femoral osteotomies.
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Background: Total hip arthroplasty (THA) in adolescent and young adults represent only about 10% of all THAs. Despite the advances in hip conservation surgery, there are still adolescents and young adults who progress to severe joint degeneration. THA seems to be the last solution in these cases. We aimed to assess the clinical and patient-related outcomes at short-term to midterm follow-up for THAs performed before the age of 20 years. Material and methods: We performed a retrospective monocentric study including all patients that underwent a THA before the age of 20 years between January 2008 and December 2018 at our tertiary orthopaedic center with a minimum follow-up of 2 years. Demographic data were recorded. The Harris and Oxford hip scores were used to assess clinical and patient-related outcomes. Results: A total of 11 patients (12 THAs) were included. Juvenile inflammatory arthritis and avascular necrosis due to slipped capital femoral epiphysis were the most commonly encountered etiologies. The mean age at surgery was 16 years (minimum 13, maximum 19 years). The mean follow-up duration was 6 years (minimum 2, maximum 9 years) without any revision. Regarding the Harris and Oxford hip scores, the mean score were 81 and 39.5 for clinical and patient-related outcomes respectively. The Spearman correlation test revealed a statistically significant positive correlation between the 2 scores of ρ = 0.811 with a P value < .001. Conclusions: THA in adolescents and young adults suffering from end-stage osteoarthritis due to pediatric hip disorders provides improved hip function and notable pain relief at short-term to midterm follow-up.
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Intramedullary lengthening nails for lower limb reconstruction in children are a rapidly growing field and represent an alternative to external fixators. Today, two types of intramedullary lengthening nails are used: motorized (FITBONE) and magnetically driven (PRECISE) bone lengthening nails. Indications for limb lengthening nails are: 1) Significant lower limb length discrepancy; 2) Short stature and deformities due to musculoskeletal or dysplastic syndromes; 3) Constitutional short stature. Intramedullary lengthening surgery is challenging and represents a safe and reliable mode of treatment in patients under 18 years of age with an excellent reported outcome.
Les clous d'allongement intramédullaires pour la reconstruction des membres inférieurs chez les enfants sont un domaine en plein essor et représentent une alternative aux fixateurs externes. Aujourd'hui, 2 types de clous d'allongement intramédullaires sont utilisés : les clous d'allongement osseux motorisés (FITBONE) et à entraînement magnétique (PRECISE). Les indications pour les clous d'allongement des membres sont les suivantes : a) inégalité significative de longueur des membres inférieurs ; b) petite taille et déformations dues à des syndromes musculosquelettiques ou à des dysplasies et c) petite taille constitutionnelle. La chirurgie d'allongement intramédullaire est exigeante et représente un mode de traitement sûr et fiable chez les moins de 18 ans, avec un excellent résultat rapporté par les patients.
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Fêmur , Desigualdade de Membros Inferiores , Humanos , Criança , Adolescente , Fêmur/cirurgia , Desigualdade de Membros Inferiores/cirurgia , Tíbia/cirurgia , Unhas , Resultado do Tratamento , Extremidade Inferior/cirurgia , Pinos OrtopédicosRESUMO
Introduction: Circumscribed or pseudomalignant myositis ossificans (MO) is a rare and benign condition characterized by heterotopic bone formation in soft tissues. The clinical presentation of MO, imaging investigations, histological findings, and treatment strategies are unclear, especially in the pediatric population. Materials and methods: A literature search was conducted in PubMed, Scopus, and Google Scholar electronic databases to identify original articles and reviews in English or French of traumatic and non-traumatic MO. Studies were selected by 2 independent reviewers following the PRISMA recommendation and descriptive data were extracted. We harvest in each case the sex, age at diagnosis, location, presence of initial trauma, pre-emptive diagnosis, modalities of imagery used, realized biopsy, treatment performed, and type of follow-up. Results: Sixty pediatric cases of MO were identified between 2002 and 2023. Twenty-three patients (38.3%) were diagnosed with idiopathic/pseudomalignant and 37 patients (61.7%) with circumscribed. The mean age at diagnosis was 9.5 years (range 0.2-17 years), with a male-to-female ratio of 1:1. The initial pre-emptive diagnosis was neoplasia in 13 patients (21.7%). The biopsy was percutaneous in 9 patients (15%) and incisional in 7 patients (11.7%). Histological analysis was achieved in 35 cases (57%). Surgical excision was the first line treatment in 46.7% of patients, and non-surgical in the remaining patients. The follow-up strategy was clinical in 16 patients (26.7%) or based on imaging investigation in 23 patients (38.3%). Discussion: Although MO in children is described as a rare pathology, identifying the benignity of the condition is essential to avoid unnecessary invasive treatment and to avoid delaying the treatment of a potentially life-threatening entity. It seems that there is no consensus established concerning the proper imaging for diagnosis. Clinicians should acknowledge that the absence of a triggering trauma tends to direct the investigation and the management toward a surgical attitude. Conservative management is key, however, surgical excision can be proposed on matured lesions on a case-by-case basis. The absence of recurrence is not excluded. Therefore, a close clinical follow-up is suggested for all cases. The true benefit of a radiological is questioned in a question known to be self-resolving.
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Background: The Tübingen splint was initially developed for the treatment of stable developmental hip dysplasia (DDH). Later on, some authors expanded its include for the treatment of unstable DDH, but there remain some controversies in the literature. This study aims to compare the outcome between stable and unstable DDH treated with a Tübingen splint. Methods: Epidemiological data and ultrasonographic data of all infants diagnosed with DDH and initially treated with a Tübingen splint at our institution between May 2017 and February 2020 were assessed retrospectively. We divided the population into stable and unstable hips using the Graf classification. Age at treatment initiation, duration of treatment, complications, and radiological outcome between 12 and 24 months were investigated. Results: We included a total of 45 patients (57 hips) affected by DDH treated with the Tübingen splint. Treatment has been successful in 93% of stable hips and only 40% of unstable hips. Radiological outcome at 1-year follow-up significantly correlated with initial Graf classification (p < 0.001). Conclusion: The Tübingen splint is a safe and effective treatment for stable hips, nevertheless, for unstable hips, closed reduction, and spica cast remains the gold standard.
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PURPOSE: About 20% of all fractures in children occur at the lower extremity. This study aims to investigate the epidemiology and injury pattern of lower extremity fractures within the pediatric population consulting a tertiary referral hospital in Switzerland. METHODS: Study population included all patients up to 16 years presenting with a lower extremity fracture over a period of one year. Recorded data were age, gender, side, season of the year, mechanism, type of fracture and applied treatment. RESULTS: Fractures of the lower extremity represent 23% of all fractures with a mean age of 9 years and 6 months. The tibia, with 94 fractures (38%), represents the most frequently injured bone. Peak incidence is seen in winter and 24% of tibia shaft fractures were due to board sports. Overall, 82% of fractures were treated by cast with or without closed reduction, and only 18% requested surgery. CONCLUSION: Board sports seems to be a leading cause of tibial shaft fracture in our region. Nevertheless, only 18% of fractures had recourse to an orthopedic surgeon, hence the importance of the teaching quality of pediatric residents for conservative fracture treatment.
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Traumatismos da Perna , Fraturas da Tíbia , Criança , Humanos , Traumatismos da Perna/complicações , Extremidade Inferior , Estudos Retrospectivos , Suíça/epidemiologia , Centros de Atenção Terciária , Fraturas da Tíbia/epidemiologia , Fraturas da Tíbia/cirurgiaAssuntos
Neoplasias Ósseas/epidemiologia , Encondromatose/epidemiologia , Encondromatose/genética , Isocitrato Desidrogenase/genética , Adulto , Neoplasias Ósseas/complicações , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Encondromatose/complicações , Encondromatose/patologia , Feminino , Predisposição Genética para Doença , Humanos , MasculinoRESUMO
INTRODUCTION: Early diagnosis and early treatment have become the gold standard for management of developmental dysplasia of the hip. Surgery is required in case of failed initial treatment. Innominate pelvic osteotomy of Salter (SIO), Pemberton's pericapsular osteotomy (PPO) and Dega's acetabuloplasty (DA) are among the most used procedures.We performed a systematic review and meta-analysis of the past 57 years in order to assess the mid- and long-term outcome of these techniques. METHODS: Studies met inclusion criteria if they: (1) reported at least 5 cases treated by 1 of the abovementioned surgical techniques; (2) included children aged between 1 and 8 years; (3) surgical indication was late detected DDH or a failed initial treatment; (4) presented a minimal follow-up of 24 months; (5) reported the radiological score of Severin and/or the clinical score of McKay.Clinical and radiological outcomes were dichotomised into favourable and unfavourable outcome and weighted summary rates were determined using meta-analysis models. RESULTS: From a total of 7391 articles, 48 level of evidence grade IV articles were included in our review. A total of 2143 cases with a mean follow up of 112.4 months were included.Pooled Severin score indicated a statistically better outcome for PPO and DA compared to SIO (p = 0.0003 and p = 0.002, respectively). By dichotomising the results in favourable and unfavourable outcome, PPO showed the best results (p = 0.0002 vs. SIO, p = 0.01 vs. DA).Pooled McKay score showed a statistically better outcome for PPO and DA compared to SIO (p < 0.0001 and p = 0.03, respectively) as well as better outcomes for PPO compared to DA (p = 0.01). By dichotomising the results in favourable and unfavourable, PPO showed the best results. CONCLUSIONS: Even if our review demonstrates slightly better radiological and clinical results with the PPO, the currently available and limited data do not allow for clear recommendation towards one of these techniques.
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Acetabuloplastia , Displasia do Desenvolvimento do Quadril , Luxação Congênita de Quadril , Criança , Seguimentos , Luxação Congênita de Quadril/diagnóstico por imagem , Luxação Congênita de Quadril/cirurgia , Humanos , Lactente , Osteotomia , Radiografia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
PURPOSE: In case of residual hip dysplasia (RHD) in children, pelvic radiographs are sometimes insufficient to precisely evaluate the entire coverage of the femoral head, when trying to decide on the need for further reconstructive procedures. METHODS: This study retrospectively compares the bony and the cartilaginous acetabular angle of Hilgenreiner (HTE) of 60 paediatric hips on pelvic MRI separated in two groups. Group 1 included 31 hips with RHD defined by a bony HTE > 20°. Group 2 included 27 hips with a HTE < 20°. They were compared by introducing a new ratio calculated from the square of cartilaginous HTE above the bony HTE on frontal MRI. The normal upper limit for this acetabular angle ratio was extrapolated from the published normal values of cartilaginous HTE and bony HTE in children. RESULTS: The acetabular angle ratio was statistically significantly increased in the hips with RHD with a mean value of 7.1 ± 4.7 compared to the hips in the control group presenting a mean value of 2.1 ± 1.9 (p < 0.00001). CONCLUSIONS: This newly introduced ratio seems to be a helpful tool to orientate the further treatment in children presenting borderline RHD.
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Acetábulo/diagnóstico por imagem , Cartilagem Articular/diagnóstico por imagem , Luxação Congênita de Quadril/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Projetos Piloto , Estudos RetrospectivosRESUMO
We describe here a rare case of septic pseudarthrosis due to Erysipelatoclostridium ramosum in a female young patient. The patient, currently in remission from Ewing's sarcoma treated by a bone resection and allograft combined with chemotherapy, suffered from a chronic femoral pseudarthrosis in a context of bone insufficiency and graft resorption. A broad range 16S PCR followed by sequencing, as well as an enrichment culture of a bone biopsy revealed the presence of E. ramosum, an anaerobic firmicute with a low Gram-positive affinity staining and low GC content, that was further characterized by whole genome sequencing (WGS).
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Clostridium/isolamento & purificação , Pseudoartrose/etiologia , Adulto , Feminino , Fêmur , HumanosRESUMO
RATIONALE: Heptadactylia is a rare congenital disorder from the polydactyly family. Polydactyly is generally classified into 3 major groups: preaxial (medial ray), postaxial (lateral ray), and central polydactyly. Most common cases are related to preaxial or postaxial polydactyly. The rarity of central polydactyly can be explained in 3 ways. First, central polydactyly with duplication appearing on metatarsal is pretty uncommon. Second, the duplication appears isolated on the foot. Polydactyly is mostly associated with other physical defects or others duplications. Last, the duplication of the digital rays does not appear once but twice concerning all the digital rays and makes 7 functional toes appear. We describe this malformation with supporting iconography and radiography as well as its surgical management and functional results. PATIENT CONCERNS: We analyzed an original case of isolated heptadactylia on the foot of a 14-month-old girl. The supernumerary toes made it impossible for the child to wear standard shoes and her parents were worried about this problem. DIAGNOSES: Clinical foot examination and radiographs revealed the presence of 7 complete rays. Every toe was composed of phalanx and metatarsal ray. There was no other congenital deformity. INTERVENTIONS: Decision was made to resect the second and third rays (the two most misaligned toes in our consideration). The first stage of surgery was the ray resection and the second stage was the reconstruction of the intermetatarsal ligament to achieve a good functional and cosmetic results. OUTCOMES: After wound healing, the child was able to walk alone while wearing normal shoes. LESSONS: We demonstrated that treatment of foot polydactyly requires careful preoperative assessment, including radiographs and photography. A good clinical evaluation of the medial polydactyly improves type-specific recognition which may enhance the accuracy of surgical treatment. Polydactyly is frequently associated with other malformations. We recommend performing a general clinical examination to exclude concomitant malformations. We recommend surgical treatment around the onset of walking.
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Polidactilia/cirurgia , Dedos do Pé/anormalidades , Feminino , Humanos , LactenteRESUMO
Osteoblastoma is a rare, benign, osteoid-producing, and slow-growing primary bone tumor, typically arising in long bones or in the spine, with a slight male predominance. This report describes the surgical treatment of a giant C-1 (atlantal) osteoblastoma diagnosed in a young male patient with neurofibromatosis Type 1. The authors describe the clinical presentation, the surgical procedure for complete excision and stabilization, and results as of the 1-year follow-up. They detail a bilateral occipitoaxial spinal interarticular stabilization technique that they used after complete tumor excision. To the best of their knowledge, this is the first case of bilateral C-1 lateral mass reconstruction by this technique to be reported in the literature.
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Neoplasias Ósseas/cirurgia , Atlas Cervical/cirurgia , Vértebras Cervicais/cirurgia , Osteoblastoma/cirurgia , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/patologia , Criança , Humanos , Masculino , Osteoblastoma/diagnóstico , Procedimentos de Cirurgia Plástica/métodos , Resultado do TratamentoRESUMO
Osteogenesis imperfecta is an inherited connective tissue disorder with wide phenotypic and molecular heterogeneity. A common issue associated with the molecular abnormality is a disturbance in bone matrix synthesis and homeostasis inducing bone fragility. In very early life, this can lead to multiple fractures and progressive bone deformities, including long bone bowing and scoliosis. Multidisciplinary management improves quality of life for patients with osteogenesis imperfecta. It consists of physical therapy, medical treatment and orthopaedic surgery as necessary. Medical treatment consists of bone-remodelling drug therapy. Bisphosphonates are widely used in the treatment of moderate to severe osteogenesis imperfecta, from infancy to adulthood. Other more recent drug therapies include teriparatide and denosumab. All these therapies target the symptoms and have effects on the mechanical properties of bone due to modification of bone remodelling, therefore influencing skeletal outcome and orthopaedic surgery. Innovative therapies, such as progenitor and mesenchymal stem cell transplantation, targeting the specific altered pathway rather than the symptoms, are in the process of development.
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Conservadores da Densidade Óssea/uso terapêutico , Denosumab/uso terapêutico , Difosfonatos/uso terapêutico , Osteogênese Imperfeita/diagnóstico , Osteogênese Imperfeita/tratamento farmacológico , Teriparatida/uso terapêutico , Fraturas Ósseas/prevenção & controle , Humanos , Osteogênese Imperfeita/cirurgia , Osteogênese Imperfeita/terapia , Modalidades de FisioterapiaRESUMO
We report two unrelated patients with a multisystem disease involving liver, eye, immune system, connective tissue, and bone, caused by biallelic mutations in the neuroblastoma amplified sequence (NBAS) gene. Both presented as infants with recurrent episodes triggered by fever with vomiting, dehydration, and elevated transaminases. They had frequent infections, hypogammaglobulinemia, reduced natural killer cells, and the Pelger-Huët anomaly of their granulocytes. Their facial features were similar with a pointed chin and proptosis; loose skin and reduced subcutaneous fat gave them a progeroid appearance. Skeletal features included short stature, slender bones, epiphyseal dysplasia with multiple phalangeal pseudo-epiphyses, and small C1-C2 vertebrae causing cervical instability and myelopathy. Retinal dystrophy and optic atrophy were present in one patient. NBAS is a component of the synthaxin-18 complex and is involved in nonsense-mediated mRNA decay control. Putative loss-of-function mutations in NBAS are already known to cause disease in humans. A specific founder mutation has been associated with short stature, optic nerve atrophy and Pelger-Huët anomaly of granulocytes (SOPH) in the Siberian Yakut population. A more recent report associates NBAS mutations with recurrent acute liver failure in infancy in a group of patients of European descent. Our observations indicate that the phenotypic spectrum of NBAS deficiency is wider than previously known and includes skeletal, hepatic, metabolic, and immunologic aspects. Early recognition of the skeletal phenotype is important for preventive management of cervical instability.
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Anormalidades Múltiplas/genética , Mutação , Proteínas de Neoplasias/genética , Anormalidades Múltiplas/etiologia , Criança , Pré-Escolar , Feminino , Humanos , Sistema Imunitário/fisiopatologia , Lactente , Hepatopatias/genética , Masculino , Atrofia Óptica/genética , Anomalia de Pelger-Huët/etiologia , Gravidez , Retina/patologia , Pele/patologiaRESUMO
Introduction. Use of Pavlik harness for the treatment of DDH can be complicated for parents. Any misuse or failure in the adjustments may lead to significant complications. An abduction brace was introduced in our institution, as it was thought to be easier to use. Aim. We assess the results for the treatment of DDH using our abduction brace in children of 0-6 months old and compare these results with data on treatments using the Pavlik harness. Method. Retrospective analysis of patients with DDH from 0 to 6 months old at diagnosis, performed from 2004 to 2009. Outcomes were rates of reduction of the hip and avascular necrosis of the femoral head (AVN). Follow-up was at one year and up to 4 years old. Results. Hip reduction was successful in 28 of 33 patients (85%), with no AVN. Conclusion. Our results in terms of hip reduction rate and AVN rate are similar to those found in literature assessing Pavlik harness use, with a simpler and comfortable treatment procedure.
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Primary rib involvement accounts for 16% of paediatric Ewing sarcoma (ES). Neo-adjuvant chemotherapy and surgical tumor resection may leave large thoracic wall defects requiring complex reconstruction in a growing individual. We report our experience in three children aged 3, 10, and 12 years, in whom single-stage resection and reconstruction were performed using a Gore-Tex Dualmesh patch, covered by a latissimus dorsi rotation flap harvested in continuity with the thoracolumbar fascia. The youngest patient also had a vertical expandable prosthetic titanium rib (VEPTR) anchored to help prevent subsequent scoliosis throughout growth.
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Músculo Esquelético , Procedimentos de Cirurgia Plástica , Politetrafluoretileno , Sarcoma de Ewing/cirurgia , Retalhos Cirúrgicos , Doenças Torácicas/cirurgia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Radiografia , Sarcoma de Ewing/diagnóstico por imagem , Doenças Torácicas/diagnóstico por imagemRESUMO
Osgood-Schlatter disease is a painful affection of the knee which touches particularly the active teenagers. Etiology of this frequent affection is unknown. This disease appears as an anterior knee pain and swelling started and worsened by the sports activities. Diagnosis is especially clinical. X-Rays, ultrasounds or IRM are not necessary for the diagnosis. Treatment is based on eviction of sports, analgesics and sometimes physiotherapy. Surgery is rarely proposed. Knee pain stops at the end of the growth. Long-term outcome is good for the majority of the patients. Some studies suggest a patella alta at the end of the growth, without an established correlation with knee arthritis.
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Osteocondrose , Humanos , Osteocondrose/diagnóstico , Osteocondrose/terapiaRESUMO
Bioresorbable scaffolds made of poly(L-lactic acid) (PLA) obtained by supercritical gas foaming were recently described as suitable for tissue engineering, portraying biocompatibility with primary osteoblasts in vitro and interesting mechanical properties when reinforced with ceramics. The behavior of such constructs remained to be evaluated in vivo and therefore the present study was undertaken to compare different PLA/ceramic composite scaffolds obtained by supercritical gas foaming in a critical size defect craniotomy model in Sprague-Dawley rats. The host-tissue reaction to the implants was evaluated semiquantitatively and similar tendencies were noted for all graft substitutes: initially highly reactive but decreasing with time implanted. Complete bone-bridging was observed 18 weeks after implantation with PLA/ 5 wt % beta-TCP (PLA/TCP) and PLA/5 wt % HA (PLA/HA) scaffolds as assessed by histology and radiography. We show here for the first time that this solvent-free technique provides a promising approach in tissue engineering demonstrating both the biocompatibility and osteoconductivity of the processed structures in vivo.
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Materiais Biocompatíveis/química , Cerâmica/química , Gases/metabolismo , Implantes Experimentais , Ácido Láctico/metabolismo , Polímeros/metabolismo , Crânio/fisiologia , Cicatrização , Animais , Materiais Biocompatíveis/metabolismo , Contagem de Células Sanguíneas , Peso Corporal , Substitutos Ósseos/metabolismo , Cerâmica/metabolismo , Citocinas/sangue , Poliésteres , Radiografia , Ratos , Ratos Sprague-Dawley , Crânio/diagnóstico por imagem , Crânio/patologia , Crânio/ultraestrutura , Engenharia TecidualRESUMO
The aim of this investigation was to test the biocompatibility of three-dimensional bioresorbable foams made of poly(L-lactic acid) (PLA), alone or filled with hydroxyapatite (HA) or beta-tricalcium phosphate (beta-TCP), with human primary osteoblasts, using a direct contact method. Porous constructs were processed by supercritical gas foaming, after a melt-extrusion of ceramic/polymer mixture. Three neat polymer foams, with pore sizes of 170, 310, and 600 microm, and two composite foams, PLA/5 wt% HA and PLA/5 wt% beta-TCP, were examined over a 4-week culture period. The targeted application is the bone tissue-engineering field. For this purpose, human fetal and adult bone cells were chosen because of their highly osteogenic potential. The association of fetal bone cells and composite scaffold should lead to in vitro bone formation. The polymer and composite foams supported adhesion and intense proliferation of seeded cells, as revealed by scanning electron microscopy. Cell differentiation toward osteoblasts was demonstrated by alkaline phosphatase (ALP) enzymatic activity, gamma-carboxylated Gla-osteocalcin production, and the onset of mineralization. The addition of HA or beta-TCP resulted in higher ALP enzymatic activity for fetal bone cells and a stronger production of Gla-osteocalcin for adult bone cells.