William Dias Belangero

Inherited risk factors for thrombophilia among children with Legg-Calvé-Perthes disease

An inherited tendency to hypercoagulability has been suggested as a cause of vascular thrombosis resulting in Legg-Calvé-Perthes disease (LCPD). Here we carried out an investigation of the most common inherited risk factors for hypercoagulability including the mutation in the factor V gene (factor V Leiden), the transition 20.210G-->A in the prothrombin gene, and also the homozygosity for the 677C-->T transition in the methylenetetrahydrofolate reductase gene (MTHFR). The investigation was carried out among 61 Brazilian children with LCPD, who were compared with 296 individuals from the general population. The prevalence of the factor V Leiden mutation was higher in LCPD patients than in the controls (4.9 vs. 0.7%; p = 0.03). However, no patient had the prothrombin gene variant, and no difference was found between patients and controls when homozygosity for MTHFR-T (3.2 vs. 2.6%: p = 0.64) was determined. These data suggest that in our population, the heterozygosity for factor V Leiden was the only inherited risk factor associated with the development of LCPD.

Relevant Aspects of Centrifugation Step in the Preparation of Platelet-Rich Plasma

Introduction. Platelet-Rich Plasma (PRP) is rich in growth factors, playing important role in tissue healing. The wide variation of reported protocols for preparation of PRP leads to variable compositions, which induce different biological responses and prevent results comparison. This study aims to highlight relevant aspects of the centrifugation step to obtain reproducible results and overall quality. Material and Methods. Samples of blood were collected from 20 healthy donors that have signed free informed consent. Two centrifugation steps (spins) were analyzed for the influence of centrifugal acceleration, time, processed volume, and platelet gradient. The Pure Platelet-Rich Plasma (P-PRP) was characterized as platelet concentration, integrity, and viability (sP-selectin measurement). Results. Lower centrifugal accelerations favour platelet separation. The processing of 3.5 mL of blood at 100 ×g for 10 min (1st spin), 400 ×g for 10 min (2nd spin), withdrawing 2/3 of remnant plasma, promoted high platelet recovery (70–80%) and concentration (5x) maintaining platelet integrity and viability. The recovery of platelets was reduced for a larger WB volume (8.5 mL) processed. Conclusion. Centrifugal acceleration, time, WB processed volume, and minimization of the platelet gradient before sampling are relevant aspects to ensure reproducible compositions within the autologous nature of PRP.

Orthopedic pathology of the lower extremities: Scintigraphic evaluation in the thigh, knee, and leg

Radionuclide imaging (RI) of the osseous and nonosseous structures of the thigh, knee, and leg provide important diagnostic and prognostic information upon which the orthopedic surgeon can base treatment planning and management decisions. 99mTc-MDP scintigraphy is essential in overuse injuries such as stress fractures and shin splints. RI is important in assessing complications of trauma. It is the only imaging modality able to assess the magnitude of physeal stimulus caused by femoral fractures and to predict a favorable or unfavorable outcome of leg length by semiquantitative analysis; SPECT imaging can detect and locate decreased metabolism associated with posttraumatic closure of the physeal plate to predict growth arrest and deformities. Three-phase bone imaging (TPBI) is essential to differentiate hypervascular from avascular nonunions and follow delayed union. In osteonecrosis of the knee, bone scintigraphy precedes radiography changes even in stage l of the disease. 99mTc-MDP and 99mTc-HIG imaging are powerful tools in determining the outcomes of osteoarthritis and rheumatoid arthritis, respectively. Bone scintigraphy can also detect chronic ligament and acute and chronic meniscal lesions. The combined use of TPBI, gallium-67 citrate imaging, and indium-111 or 99mTc-HMPAO labeled leukocytes is important to diagnose and differentiate acute from chronic osteomyelitis, and to detect infected knee prostheses. Thallium-201 chloride imaging and 99mTc-sestamibi imaging have an important role in the assessment of tumor response to chemotherapy and in the quantification of tumor viability.

Análise da interface formada entre o polifluoreto de vinilideno (piezelétrico e não piezelétrico) e o tecido ósseo de ratos

O objetivo deste estudo foi analisar a interface formada entre o poli(fluoreto de vinilideno) (PVDF - piezeletrico e nao piezeletrico) e o tecido muscular e osseo do rato. Foram utilizados 40 tubos de PVDF [P(VDF-TrFE)] piezeletricos com coeficiente de piezeletricidade de d3h = 2,5 pC/N e capacitância 800 pF/m e 40 tubos de PVDF nao piezeletricos. Em vinte animais foram implantados 40 tubos de PVDF piezeletricos e nos outros vinte, 40 tubos de PVDF nao piezeletricos, seguidos por 7 dias, 3, 6 e 12 semanas. Os tubos foram implantados na regiao intercondiliana do femur da pata posterior esquerda e no corpo do musculo triceps sural da pata posterior direita. A interface formada pelos tubos com o tecido muscular (n=40) e osseo (n=32) foi estuda por microscopia optica convencional e os tubos retirados por microscopia eletronica de varredura (n= 72). A MEV por retroespalhado foi realizada para o estudo da interface entre o tubo e o tecido osseo nao descalcificado (n = 8). Ao redor dos tubos implantados no tecido muscular houve formacao de capsula com ausencia de macrofagos e celulas gigantes. A retirada dos tubos piezeletricos, tanto do tecido muscular quanto do tecido osseo, foi sempre mais dificil do que a dos tubos nao piezeletricos, devido a aderencia dos primeiros no leito receptor. A microscopia eletronica de varredura demonstrou maior aderencia e crescimento de tecido conjuntivo sobre os tubos de PFVD piezeletricos. Ao redor e no interior dos tubos de PVDF piezeletricos implantados no tecido osseo pode se observar, apos 12 semanas, crescimento evidente de tecido osseo, principalmente no interior do tubo. A microscopia eletronica por retroespalhamento tambem demonstrou a presenca de tecido osseo somente no interior dos tubo piezeletricos, apos 12 semanas. Os resultados indicam que a piezeletricidade teve papel importante na neoformacao, tanto do tecido osseo quanto do tecido conjuntivo denso. Provavelmente, essa neoformacao foi decorrente de microdeformacoes produzidas nos tubos piezeletricos, oriundas da contracao do musculo triceps sural e da pressao intraarticular gerada pelo movimento articular e pela marcha Abstract

Biomechanical and histological evaluation of hydrogel implants in articular cartilage

We evaluated the mechanical behavior of the repaired surfaces of defective articular cartilage in the intercondylar region of the rat femur after a hydrogel graft implant. The results were compared to those for the adjacent normal articular cartilage and for control surfaces where the defects remained empty. Hydrogel synthesized by blending poly(2-hydroxyethyl methacrylate) and poly(methyl methacrylate-co-acrylic acid) was implanted in male Wistar rats. The animals were divided into five groups with postoperative follow-up periods of 3, 5, 8, 12 and 16 weeks. Indentation tests were performed on the neoformed surfaces in the knee joint (with or without a hydrogel implant) and on adjacent articular cartilage in order to assess the mechanical properties of the newly formed surface. Kruskal-Wallis analysis indicated that the mechanical behavior of the neoformed surfaces was significantly different from that of normal cartilage. Histological analysis of the repaired defects showed that the hydrogel implant filled the defect with no signs of inflammation as it was well anchored to the surrounding tissues, resulting in a newly formed articular surface. In the case of empty control defects, osseous tissue grew inside the defects and fibrous tissue formed on the articular surface of the defects. The repaired surface of the hydrogel implant was more compliant than normal articular cartilage throughout the 16 weeks following the operation, whereas the fibrous tissue that formed postoperatively over the empty defect was stiffer than normal articular cartilage after 5 weeks. This stiffness started to decrease 16 weeks after the operation, probably due to tissue degeneration. Thus, from the biomechanical and histological point of view, the hydrogel implant improved the articular surface repair.

Less invasive percutaneous wave plating of simple femur shaft fractures: A prospective series

In developing nations, fixation of femoral shaft fractures with intramedullary (IM) nails can pose significant challenges. Use of IM implants is commonly limited by availability, funds or patients physique. Conversely, traditional compression plates are usually readily available at a much lower cost, making bridge plating of femur fractures a frequently used surgical technique. We hypothesised that less invasive percutaneous plate osteosynthesis (MIPPO) of femoral shaft fractures has a similar outcome compared to IM nailing. The study is designed as a prospective case series at a Level 1 university trauma centre. Fifty-seven patients with simple femur shaft fractures (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) type A) were enrolled between April 2001 and December 2005 and followed up for a minimum of 1 year or until fracture union. Primary outcome measures included union rate and time to union. Secondary outcome parameters were hardware failure, malalignment, infection and need for revision surgery. The mean age of the study cohort was 24.7 years. Fifty-four patients sustained associated systems injury. Primary union occurred in 54 patients in an average time of 13 weeks. Two patients presented with implant failure, and one patient displayed signs of delayed union. Six patients developed valgus deformities, whereas five patients displayed external rotation malalignment. One patient developed a superficial wound infection, and another presented with a deep infection. Bridge wave plating represents a safe and efficacious treatment alternative to IM nailing for simple femoral shaft fractures in countries where IM nails are limited by availability, costs and patients physical characteristics.

Prediction and Modulation of Platelet Recovery by Discontinuous Centrifugation of Whole Blood for the Preparation of Pure Platelet-Rich Plasma

Abstract The aim of this study was to describe the behavior of the separation of red blood cells (RBCs) by discontinuous centrifugation (DC) of whole blood to modulate and control the platelet recovery in the preparation of pure platelet-rich plasma (P-PRP). P-PRP is a platelet-rich plasma (PRP) in which the white blood cell layer is not included. To achieve this goal, an analytical model was derived that takes into account the packing of RBCs and predicts the behavior of platelet and plasma recovery efficiencies (PtPlRE) based on the volume of whole blood, the hematocrit, and the volume of supernatant, as a function of the operating variables, centrifugal acceleration, and time. The model was derived from the basic equation of DC, which originates from the equilibrium balance of forces on a particle, and included the addition of one factor that corrected the terminal velocity of RBCs and was also correlated to the PtPlRE in the supernatant. This factor was the ratio between the fractional volume concentrations of plasma and RBCs in the centrifugation pellet after centrifugation. The model was validated and the variability of the data was determined using experimental data from 10 healthy donors in the age range of 25–35 years. The predicted behavior for the packing of RBCs and the PtPlRE was consistent with the behavior seen in the experimental data. Thus, the PtPlRE could be modulated and controlled through centrifugal acceleration, time, and hematocrit. Use of this model based on a physical description of events is the first step of a reliable standardization of PRP preparations.

Avaliação da qualidade de vida em pacientes idosos um ano após o tratamento cirúrgico de fraturas transtrocanterianas do fêmur

OBJETIVO: Avaliar o impacto que as fraturas transtrocanterianas produzem sobre a qualidade de vida de pacientes idosos, tratados cirurgicamente, durante o periodo de um ano de acompanhamento. MATERIAL E METODO: Foram selecionados 73 idosos com fratura transtrocanterina, com idade igual ou superior a 65 anos de ambos os sexos. Foi aplicado questionario padronizado, para se obter informacoes quanto aos habitos de vida, atividade fisica, funcionalidade, deambulacao e estado cognitivo. Foram excluidos os obitos ocorridos durante o estudo, pacientes que nao deambulavam, com doencas neurologicas ou fraturas patologicas. RESULTADOS: A media de idade foi 80,17 ± 7,2, sendo 75% do sexo feminino. Ao comparar as somatorias das atividades de vida diaria (p=0,04) e instrumentais da vida diaria (p=0,004), obtidas na pre e pos-fratura, os pacientes tornaram-se mais dependentes pos-fratura. Atividades de vida diaria que apresentaram piora pos-fratura foram: tomar banho (p=0,04), ir ao banheiro (p=0,02) e vestir-se (p=0,04). Todas as atividades instrumentais da vida diaria apresentaram diferenca significativa, apresentando maior dependencia funcional pos-fratura, assim como aumento da necessidade de auxilio a deambulacao (p=0,00002), idade avancada (p=0,01) e nao realizar atividades domesticas (p=0,01). A baixa pontuacao no teste Minimental estava associada com uma maior dependencia para realizar as atividades da vida diaria na pre-fratura (p=0,00002) e pos-fratura (p=0,01). CONCLUSAO: Apos um ano, as atividades de vida diaria que dependiam dos membros inferiores pioraram significativamente, todas as atividades instrumentais de vida diaria apresentaram piora significativa em mais de 50% dos pacientes e mais da metade dos pacientes que andavam sem apoio perderam esta capacidade.

Labrum repair combined with arthroscopic reduction of capsular volume in shoulder instability

We performed arthroscopic treatment of traumatic anterior and anteroinferior shoulder instability combining three procedures— labrum repair, reduction of capsular volume and suture of the rotator cuff interval—with the aim of analysing the results with regard to stability and function. Between January 1999 and December 2003, 27 patients underwent arthroscopic treatment for labrum repair with metal anchors, reduction of capsular volume through thermal capsulorrhaphy and suture of rotator cuff interval. These patients were evaluated in the pre- and postoperative period using the UCLA and Rowe scales and in the postoperative period using the ASES scale. During a mean follow-up period of 32.4 months (range 22–74 months) all shoulders remained stable. Using the UCLA scale, there was improvement from the preoperative period, with a mean score of 24.7, to the postoperative period, with a mean of 32.81. Improvement was also shown by the Rowe scale, with a mean score of 39.81 in the preoperative period and 90.74 in the postoperative period. On the ASES scale the mean score was 92.22. All shoulders remained stable and there was marked functional improvement in the patients who were treated. These results are comparable to those obtained with open surgery, observing similar patient selection criteria.RésuméNous avons réalisé le traitement arthroscopique de l’instabilité de l’épauleen associant trois techniques, réparation du labrum, ligature capsulaire et suture de la coiffe. L’analyse des résultats de ces techniques a porté sur la stabilité et sur l’amélioration de la fonction articulaire. De janvier 1999 à décembre 2003, 27 patients ont été traités selon ces techniques,réparation du labrum utilisant des ancres métalliques, la réduction capsulaire étant réalisée par une capsuloraphie et les lésions de la coiffe étant suturées. Ces patients ont été évalués en pré et post-opératoire à l’aide des scores UCLA et Rowe et en post-opératoire avec le score ASES. Pendant toute la période de suivi 32,4 mois (22–74), les épaules sont restées stables , le score UCLA a montré une amélioration des patients (24.7 en pré-opératoire, 32.81 en post-opératoire). Ces patients ont également été améliorés comme le montre le score Rowe avec une moyenne de 39.81 en pré-opératoire à 90.74 en post-opératoire. Les scores de l’ASES ont montré une moyenne de 92.22. Conclusion : toutes les épaules sont restées stables avec une importante amélioration fonctionnelle des patients opérés. Ces résultats sont comparables aux résultats obtenus par une chirurgie à ciel ouvert si l’on compare les patients et les critères de sélection.

Osteossíntese de fratura diafisária do úmero com placa em ponte: apresentação e descrição da técnica

The authors describe for the first time ever a minimally invasive plate osteosythesis for the treatment of the humeral shatf fractures. After anatomic human cadavers studies, it was identified three surgical approaches for plate percutaneous insertion on the anterior surface of the humerus without vascular and nervous injury. The proximal approach is between the biceps and deltoid muscles. The distal approach for medial third fractures is between the biceps brachialis and brachialis muscles. The plate is inserted from the proximal to distal direction. For distal fractures, the proximal approach is the same described by Krocher, with the plate inserted from distal to proximal and fixed on the anterior surface of the lateral column of the humerus. This method has been used since June/2001 mainly for the treatment of multiple trauma patients, allowing other surgical procedures, and it has been showed very efficient. The patient is operated in DHD without image intensifier or x ray apparatus. Until the moment, 22 patients have been treated without vascular or nervous complications.