Medullar Canal Research Articles

Bi-allelic variations in CRB2, encoding the crumbs cell polarity complex component 2, lead to non-communicating hydrocephalus due to atresia of the aqueduct of sylvius and central canal of the medulla

Congenital hydrocephalus is a common condition caused by the accumulation of cerebrospinal fluid in the ventricular system. Four major genes are currently known to be causally involved in hydrocephalus, either isolated or as a common clinical feature: L1CAM, AP1S2, MPDZ and CCDC88C. Here, we report 3 cases from 2 families with congenital hydrocephalus due to bi-allelic variations in CRB2, a gene previously reported to cause nephrotic syndrome, variably associated with hydrocephalus. While 2 cases presented with renal cysts, one case presented with isolated hydrocephalus. Neurohistopathological analysis allowed us to demonstrate that, contrary to what was previously proposed, the pathological mechanisms underlying hydrocephalus secondary to CRB2 variations are not due to stenosis but to atresia of both Sylvius Aqueduct and central medullar canal. While CRB2 has been largely shown crucial for apico-basal polarity, immunolabelling experiments in our fetal cases showed normal localization and level of PAR complex components (PKCι and PKCζ) as well as of tight (ZO-1) and adherens (β-catenin and N-Cadherin) junction molecules indicating a priori normal apicobasal polarity and cell–cell adhesion of the ventricular epithelium suggesting another pathological mechanism. Interestingly, atresia but not stenosis of Sylvius aqueduct was also described in cases with variations in MPDZ and CCDC88C encoding proteins previously linked functionally to the Crumbs (CRB) polarity complex, and all 3 being more recently involved in apical constriction, a process crucial for the formation of the central medullar canal. Overall, our findings argue for a common mechanism of CRB2, MPDZ and CCDC88C variations that might lead to abnormal apical constriction of the ventricular cells of the neural tube that will form the ependymal cells lining the definitive central canal of the medulla. Our study thus highlights that hydrocephalus related to CRB2, MPDZ and CCDC88C constitutes a separate pathogenic group of congenital non-communicating hydrocephalus with atresia of both Sylvius aqueduct and central canal of the medulla.

Radial tuberosity anatomy in intramedullar repair of distal biceps tendon ruptures. A radiological study.

The aim of this study was to measure cortex thickness and medullar canal width of the bicipital tuberosity, to evaluate the accessibility of a intramedullar fixation device and the resistance to pullout strengths of the anterior cortex. The final objective was to determine the length of tendon ingrowth size that will be expected when using this surgical technique. A total of 144 computer tomography images of the proximal radius were used. Bone thickness of the anterior and posterior cortex and medullar canal size were measured. The possible ingrowth of the tendon was measured both for an anatomical and non- anatomical reinsertion. Statistical and concordance analyses of results were performed. The average width of the medullar canal was 8,7mm proximal, 7,9mm distal and 7,7mm at the tuberosity. The average posterior and anterior cortex measured respectively 2,5mm and 2,9mm proximal, 3,2mm and 3,2mm distal and 2,8mm and 1,9mm at the radial tuberosity. The possible non-anatomical ingrowth was 7,6 mm on average and the possible anatomical ingrowth was 7,6mm on average. The radial tuberosity anatomy can accommodate the new distal biceps fixation device. The anterior cortex on which the new device relies for support has a similar thickness as the posterior cortex used in bicortical fixation devices which may suggest similar resistance to pull-out strengths. The availability for intra-osseous fixation of the tendon stump may avoids tendon gapping. The intra-osseous length for the tendon stump surpassed reported tendon slippage during mobilization and active contraction of the distal biceps tendon.

Influence of fetal bone tissue on reparative bone regeneration (experimental study)

The study was performed in 48 rabbits. After 1 cm resection of central part of radius diaphysis the defect was substituted with fragments of fetal tissue. Sixteen rabbits made up a control group. It was shown that fetal bone tissue stimulated reparative bone regeneration. Its fragments were not the centers of osteogenesis but bone development started within preserved periosteum and endosteum, i.e. in the location of cambial cells of osteodifferone. There were several stages of damaged bone full value structure restoration: 1) filling of the defect with fibrillar connective tissue surrounding the fragments of fetal bone tissue; 2) development of reticulo-fibrotic bone regenerate with fragments of fetal bone tissue; 3) remodeling and formation of laminar bone regenerate; 4) restoration of medullar canal with bone marrow. Restoration of damaged radius structure was accompanied by periosteal reaction and focal resorption of undamaged ulnar both at the defect level and outside the defect. In control group full value restoration of damaged bone was observed in no case

Effect of selenium nanoparticles and mannan oligosaccharide supplementation on muscle and lymphoid histomorphometry and morphometry of tibia bone in broilers reared under high stocking density

The current study investigated the potential of selenium-nanoparticles (SeNPs) and mannan-oligosaccharide (MOS) supplementation in ameliorating the high stocking density (HSD) stress on breast muscle, immune organs, and tibia bone in broilers. Three hundred and ninety two (392) day-old Ross chicks were divided in seven groups with eight replicates each (n = 7): as NSD [basal diet (BD) + normal stocking density: 10 chicks/m$^{2}$], HSD (BD + high stocking density: 16 chicks/m$^{2}$), Se-HSD [BD + Selenium (Se) 0.15 mg/kg of BD], MOS-HSD (BD + MOS 05 g/kg of BD), Se-MOS-HSD (BD + Se 0.15 mg/kg of BD + MOS 05 g/kg of BD), SeNP-HSD (BD + SeNP 0.15 mg/kg of BD), and SeNP-MOS-HSD (BD + SeNP 0.15 mg/kg of BD + MOS 05 g/kg of BD). HSD decreased (p < 0.05) breast muscle fibre diameter, density and area, pH at 0 h, pH at 24 h postslaughter, and water holding capacity (WHC), area of lymphoid tissue in caecal tonsil and bursa of Fabricius, tibia bone morphometric parameters, and Se and Copper (Cu) concentrations in bone, muscle, and serum in the HSD group compared to the NSD group. Breast muscle fibre diameter and density increased (p < 0.05) in the Se-MOS-HSD and SeNP-MOS-HSD groups and WHC only increased (p < 0.05) in the SeNP-MOS-HSD group. The area of lymphoid tissue in caecal tonsil and bursa of Fabricius increased (p < 0.05) in the SeNP-MOS-HSD group. The tibia bone weight, medullar canal diameter, tibio-tarsal index, weight/length index, and ash% improved (p < 0.05) in the SeNP-HSD and SeNP-MOS-HSD groups. Se and Cu concentration improved (p < 0.05) in bone, muscle, and serum of the Se-MOS-HSD, SeNP-HSD, and SeNP-MOS-HSD groups. We concluded that supplementation of SeNPs-MOS proved to be a more superior combination in mitigating HSD stress on breast muscle, lymphoid organs, and tibia bone.

Treatment outcomes of using paraosseous clamp and cerclage stabilisation technique in long bone fractures of cats: a retrospective study

The stabilisation technique of paraosseous clamp and cerclage has become one of the most widely used current techniques because of the easy of applicability and low cost. It is a relatively new method providing rigid fixation in the treatment of fractures, especially those which do not have sufficient cortex resistance and have a wide medullar canal in the period when the long bones of the extremity have not completed development. The technique is based on binding 3 double cerclage wires to each other to form a paracortical belt. The aim of this study was to evaluate the clinical and radiological results of fractures in the extremity long bones of cats treated with the new stabilisation method of paraosseous clamp and cerclage. The study group was formed of 14 cats of various breeds and ages, of both genders, diagnosed with a fracture of the extremity long bone. Clinical and radiographical follow-up examinations were made at 10, 30, and 45 days postoperatively. Clinical healing was achieved in 13 cases on postoperative day 45, and those cases could use the affected extremity. A correlation was determined between the functional healing results and low complication rates, including unstable fractures, and it is supported that this technique could be use of this technique in the treatment of long bone fractures. In conclusion, the results of this study demonstrated that the paraosseous clamp and cerclage stabilisation technique can be used as an alternative method in the treatment of long bone fractures, especially in indicated cases.

‘In-Out-In’ K-wires sliding in severe tibial deformities of osteogenesis imperfecta: a technical note

Severe infant osteogenesis imperfecta requires osteosynthesis. Intramedullary tibia’s osteosynthesis is a technical challenge given the deformity and the medullar canal’s narrowness. We describe an extramedullary technique: ‘In-Out-In’ K-wires sliding. We performed an anteromedial diaphysis approach. The periosteum was released while preserving its posterior vascular attachments. To obtain a straight leg, we did numerous osteotomies as many times as necessary. K-wires (‘In’) were introduced into the proximal epiphysis, and the medial malleolus (‘Out’) bordered the cortical and (‘In’) reach their opposite metaphysis. K-wires were cut, curved and impacted at their respective epiphysis ends to allow a telescopic effect. All tibial fragments are strapped on K-wires, and the periosteum was sutured over it. Our inclusion criteria were children with osteogenesis imperfecta operated before 6 years old whose verticalization was impossible. Seven patients (11 tibias) are included (2006–2016) with a mean surgery’s age of 3.3 ± 1.1 years old. All patients received intravenous bisphosphonates preoperatively. The follow-up was 6.1 ± 2.7 years. All patients could stand up with supports, and the flexion deformity correction was 46.7 ± 14.2°. Osteosynthesis was changed in nine tibias for the arrest of telescoping with flexion deformity recurrence and meantime first session-revision was 3.8 ± 1.7 years. At revision, K-wires overlap had decreased by 55 ± 23%. Including all surgeries, three distal K-wires migrations were observed, and the number of surgical procedures was 2.5/tibia. No growth arrest and other complications reported. ‘In-Out-In’ K-wires sliding can be considered in select cases where the absence of a medullary canal prevents the insertion of intramedullary rod or as a salvage or alternative procedure mode of fixation. It can perform in severe infant osteogenesis imperfecta under 6 years old with few complications and good survival time.

Conservative treatment of cervical intervertebral disc disease in a dog with the use of a cervical collar: case report

Intervertebral Disc Disease (IVDD) is the main spinal cord disease in dogs, especially of chondrodisthrophic breeds, and it’s characterized by structural degeneration of discs, following protrusion or extrusion of debris to the medullar canal, compression and variable degrees of pain, paresis and ataxia. Surgical descompressive intervention coupled with disc fenestration are the treatment of choice as it promotes faster recovery with higher succes rates, not withou important morbidity and mortality. The conservative management is considered when the pacient has mild clinical signs, doesn’t have severe medullar compression or contusion lesions on imaging tests, as well as when there are restrictions associated with the clinical state of the pacient or the higher costs of surgical treatment.

FORENSIC MORPHOLOGICAL SIGNS CHARACTERIZING STABILITY OF THE FEMUR, TIBIA AND FIBULA DURING EFFECT OF EXTERNAL DESTRUCTIVE LOAD

Introduction: Fractures of the lower limb bones very often become the subject of forensic expertise when experts have to determine the mechanisms of fracture formation, make retrospective restoration of conditions of their occurrence, solve the issues concerning the possibility of their formation under certain conditions. The aim of study is directed to investigation of morphological signs facilitating solidity of the osseous tissue of the lower limb long tubular bones, and therefore, promoting biochemical processes of their destruction in case of external traumatic impact. Materials and methods: Expert investigations included 128 injuries of the long tubular bones of the lower limb: femoral bone - 40 cases, tibia - 46, fibula - 42. Fractures of every bone were assessed by the three thirds: proximal, middle and distal. All the 29 macroscopic and 8 microscopic morphological signs of the osseous tissue were examined. Control studies were carried out on 576 specimens of the femoral bone, tibia and fibula (192 specimens of each), removed from dead males and females aged from 24 to 70. Results: The most valuable morphological signs forming "modulus of stability" are: length of plastic deformity zones from the site of stretching and compression, deviation angle of sphenoid cracks together with the character of traumatic injury impact. An important value in this respect belongs to the square of the medullar canal, length of the biggest sphenoid crack, number of longitudinal cracks and shape of the medullar canal from the site of compression, total mineral content and the height of the biggest crest in the rupture zone. Conclusions: "Modulus of stability" of the osseous tissue of the long tubular bones of the lower limb most accurately reflects interaction of traumatic mechanical impact with the bone structures during their injuries that should be considered in forensic practice in the process of making expertise.

Intraoperative bleeding in patients with osteogenesis imperfecta type III treated by Fassier-Duval femoral rodding: analysis of risk factors.

The surgical treatment of osteogenesis imperfecta (OI) is negatively influenced by clinical features such as osteoporosis, limb deformities and bone changes caused by bisphosphonate therapy. Blood loss during femoral nailing surgeries in patients with OI is a serious problem. Platelet anomalies have been associated with an elevation of the serum pyrophosphate originating from the platelets during clotting, even if the causality with the platelet dysfunction has not yet been established. To identify predictive risk factors regarding intraoperative bleeding, a retrospective analysis was conducted on 23 patients aged between 6 and 13 years, affected by OI type III, who were treated to correct femoral deformities or to perform an osteosynthesis for femoral shaft fractures, using the Fassier-Duval telescopic nail. Osteotomies were performed in 14 cases of deformities and in two out of seven cases of fractures. A survey about the bleeding had been obtained by calculating the sum of the blood aspirated and that lost with the gauzes or present on the surgical drapes. To obtain an estimate of the intraoperative blood losses, one must resort to a calculation based on an algorithm that evaluates the ratio between the effective blood loss divided by the total blood volume expected as per age and weight (γ distribution). The average blood loss was 237.4 ml (0.12 γ). In seven cases, it was necessary to perform postoperative transfusions, owing to an average blood loss of 502.8 ml (0.27 γ). Patients aged less than 10 years had a minor blood loss. A greater number of osteotomies was associated with a significant increase of average bleeding (P=0.046). Patients who were never treated with bisphosphonates showed a significantly greater bleeding rate (P=0.048). Patients affected by OI type III have a high risk of severe blood loss during surgery, even caused by the platelet disfunction, which characterizes this OI type. In addition to this predisposing factor, there are other risk factors to consider in preoperative surgical planning. In patients who were never treated with bisphosphonates, the bleeding was higher than in the ones treated with bisphosphonates since at least 1 year. The effects of bisphosphonates on bone tissue (such as the medullar canal narrowing and the bone cortex thickening) could reduce the spongious bone amount and the bleeding. Inhibiting the farnesyl pyrophosphate synthase enzyme and reducing the prenylation of many plasma proteins, including the methylene tetrahydrofolate reductase, the bisphosphonates could lead to an alteration of the coagulation cascade. The correlation found with the intake of bisphosphonates, capable of inhibiting the action of the farnesyl pyrophosphate synthase enzyme, thus influencing coagulation, requires further prospective studies with research of the methylene tetrahydrofolate reductase mutation in patients with OI type III undergoing surgical procedures. The number of osteotomies, the patient's age and the intake of bisphosphonates for at least 1 year seem to be the best predictive factors for blood loss.

Adaptive radiotherapy for head and neck tumors

Introduction Intensity modulated radiotherapy (IMRT) improves the quality of life for patient treated for head and neck tumors. This improvement can be optimized if the treatment is adapted to the anatomical variations occurring during the treatment [1] , [2] . The aim of this study is to provide a fast and accurate method for replanification, in order to define new criteria of decision in treatment adaptation. Methods The study includes 3 patients treated by IMRT technique with a simultaneous integrated boost (SIB). For each patient, a planification computed tomography scan and a weekly CBCT (Cone Beam Computed Tomography) are performed. An elastic registration is performed with the RayStation treatment planning system (RaySearch, V 5.0.2) to propagate the structures and dose distribution from the initial CT scan to the CBCT. The quality of the propagation of the structures is evaluated with the DICE index, compared to the delineation of the radiotherapist. The distortion of the dose distribution is also evaluated. Finally, the totalized dose distribution is calculated in order to analyze the impact of the adaptation of the treatment. Results Firsts results shows a mean Dice index of 0,8 for the thyroid, 0,7 for the medullar canal, 0,7 for mandibles, 0,7 for CTVs and 0,7 for parotids. The mean dose difference between the planification and the delivered dose shows a decrease of 5% for the CTVs and an increase of 4% for the parotids. Other results are still processing. Conclusion This study proposes a method for evaluating the delivered dose for head and neck tumors treated by IMRT techniques. The delivered dose could be an effective tool when comes the decision of a replanification during the treatment.

Chronic Hyperglycemia Modulates Rat Osteoporotic Cortical Bone Microarchitecture into Less Fragile Structures.

There is controversy concerning the diabetes impact on bone quality, notorious in type 2 diabetic postmenopausal women. One pointed cause might be uncontrolled glycemia. In this study, the effect of chronic hyperglycemia in bone turnover, morphology, and biomechanics was evaluated in female Wistar rats in the presence/absence of estrogens (ovariectomy). Animals (n = 28) were divided into sham, ovariectomized (OVX), hyperglycemic (streptozotocin 40 mg/kg, single-dose i.p.-STZ), and hyperglycemic-ovariectomized (STZ + OVX) animals. Blood biomarkers were estimated 60 days postovariectomy. Body weight, vertebral microarchitecture (L4-histomorphometry), femur biomechanical properties (bending tests), tibia ultrastructure (scanning electron microscopy), and femur and urinary calcium (atomic absorption) were also evaluated. The increased PINP/CTX ratio of hyperglycemic animals and the similar ratio between STZ + OVX and healthy animals contrasting with the lower ratio of OVX (in line with its histomorphometric data) suggest a tendency for improved bone formation in hyperglycemic-ovariectomized animals. The increased tibia medullar canal, which contrasts with the unaffected cortical thickness of both hyperglycemic groups while that of OVX decreased, was associated to the increased stiffness and strength of STZ + OVX bones compared to those of OVX, in line with the observed ultrastructure. Concluding, chronic hyperglycemia in ovariectomized female rats causes bone morphological changes that translate positively in the ultrastructure and mechanical properties of cortical bones.

Assessing heating distribution by therapeutic ultrasound on bone phantoms and in vitro human samples using infrared thermography.

BackgroundBioheat models have been proposed to predict heat distribution in multilayered biological tissues after therapeutic ultrasound (TUS) stimulation. However, evidence on its therapeutic benefit is still controversial for many clinical conditions. The aim of this study was to evaluate and to compare the TUS heating distribution on commercially available bone phantoms and in vitro femur and tibia human samples, at 1 MHz and several ultrasonic pulse regimens, by means of a thermographic image processing technique.MethodsAn infrared camera was used to capture an image after each 5-min 1-MHz TUS stimulation on bone phantoms, as well as in vitro femur and tibia samples (N = 10). An intensity-based processing algorithm was applied to estimate temperature distribution. Sections of five femurs in the coronal plane were also used for the evaluation of heat distribution inside the medullar canal.ResultsTemperature increased up to 8.2 and 9.8 °C for the femur and tibia, respectively. Moreover, the temperature increased up to 10.8 °C inside the medullar canal. Although temperature distributions inside the region of interest (ROI) were significantly different (p < 0.001), the average and standard deviation values for bone phantoms were more similar to the femur than to the tibia samples. Pulsed regimens caused lower increments in temperature than continuous sonication, as expected.ConclusionsCommercially available bone phantoms could be used in research focusing on thermal effects of ultrasound. Small differences in mean and standard deviation temperatures were observed between bone samples and phantoms. Temperature can reach more than 10 °C inside the medullar canal on a fixed probe position which may lead to severe cellular damage.

Pitfalls in implantation of InterTAN for intertrochanteric femur fracture

Objective To investigate the intraoperative technical difficulties in the implantation of InterTAN for intertrochanteric femur fracture and their countermeasures. Methods A retrospective study was conducted of the 496 patients with intertrochanteric femur fracture who had been treated with InterTAN intramedullary nails from September 2008 to August 2013 at our department. They were 172 men and 324 women, aged from 32 to 87 years at the time of fracture (average, 69.2 years). According to the AO classification, 29 cases were type 31-A1, 315 cases type 31-A2 and 152 cases type 31-A3. Intraoperative difficulties in implantation of InterTAN intramedullary nails were analyzed and countermeasures were proposed. Results We identified intraoperative technical difficulties in implantation of the main nail in the following situations: in 21 patients who had anatomic variation in femoral shaft (excessive anterior or lateral skewing), in 5 obese patients in one of whom iatrogenic fracture occurred; in 3 elderly patients, and in 17 patients with hard reduction in one of whom iatrogenic fracture occurred during the locking of a distal screw. Conclusions To deal with the difficulties in implantation of InterTAN for intertrochanteric femur fracture we propose the following 4 countermeasures: 1. Anteroposterior and lateral radiographs of the full length of the injured femur are necessary for preoperative determination of presence or absence of anatomical variations so that implantation can be adjusted during surgery. 2. Vertical trajectory and sufficient reaming in the medullar canal of the proximal femur are important to reduce the possibility of iatrogenic fracture, particularly in obese patients. 3. Violent hammering is prohibited and full reaming is recommended in the elderly whose bone is fragile. 4. For the cases where hard fracture reduction is predicted by the preoperative evaluation, the strategy of open reduction and fixation with dynamic hip screws seems more rational or should be prepared as an alternative method. Key words: Hip fractures; Fracture fixation, internal; Bone nails; Implantation difficulties

Clavo endomedular con cemento con antibióticos

IntroductionNonunion is the arrest of the consolidation process of a bone fracture, justified by the absence of clinical and radiographic signs of fusion, in a maximum period established (9 months) and that required surgery for its resolution.In the case of a septic nonunion, micro-organisms involved in this disease benefit from the loss of fracturary hematoma and colonize this focus, creating a biofilm that protects them. Among these, the most common is Staphylococcus aureus. ObjectiveTo assess the treatment of septic nonunion of tibia using nail cement with antibiotic. Materials and methodsWe evaluated 4 patients with open fractures of tibia, between 2007 and 2013, which received different initial treatments to solve their fractures and that concluded with septic nonunion in all cases. All 4 patients were reoperated in order to eliminate the infectious focus and were placed with a nail of cement prepared with antibiotics at the same time. ResultsThe patients negativized crops between the 3rd and 13th month after the nail with cement with antibiotics was placed. In all cases, laboratory paramethers normalized one week after the procedure. The definitive consolidation of fractures was only achieved in one case, while the rest were reoperated after 6 months of absence of radiographic evidence of consolidation. Consolidation between 4 and 6 months after the last surgery was finally achieved. DiscussionIn this work, we have found that the nail with cement with antibiotic is a valid option for the treatment of septic nonunion of tibia, not only to achieve resolution of the infection, but it is also improving the subsequent bone consolidation. ConclusionWe believe that the endomedular nail of cement with antibiotics, prior reaming of the medullar canal, is a technique with encouraging results for the treatment in septic nonunion of tibia. It provides relative fracture stability, higher simplicity in handling soft parts and consolidation facilities. Evidence levelI.

Topical hemostatic procedures control blood loss in bilateral cemented single-stage total knee arthroplasty

Background Blood management is critical in total knee arthroplasty (TKA). In bilateral, single stage TKA, blood loss seems more prominent. We believe it is important to control all potential bleeding within the wound tissue.Purpose The purpose of the study was to evaluate a series of topical procedures used to reduce blood loss and transfusion in single-stage bilateral cemented total knee arthroplasty: antifibrinolysis with tranexamic acid, vasoconstriction with epinephrine, sealing of the bone section intraoperatively, and closure of the drainage tube within the first 4 h postoperatively.Materials and methods Patients with osteoarthritis of the knees were randomly divided into two groups. In group A, 5 ml (25 mg/ml) tranexamic acid (TXA) and 5 ml analgesic containing epinephrine (3 μg/ml) solution were injected at several points into the posterior capsule before installation of the prosthesis. The femoral medullar canal was closed with autograft bone and then sealed compressively with cement. Before the tourniquet was released, 10 ml TXA solution and 10 ml analgesic containing epinephrine were injected at several points into the periosteum, synovium, joint capsule, tendons, and deep fascia tissue (injection of analgesic containing epinephrine into subcutaneous fat and dermis was avoided). The residual nail holes in the bone and the uncovered bone section were covered with bone wax. The tourniquet was then removed, and active bleeding points were stanched. TXA solution (20 ml) was injected into the articular cavity after wound closure. The drainage tube was clamped for 4 h, then opened. In group B, injection of analgesic containing epinephrine into soft tissue, control of active bleeding, and clamping of the drainage tube for 4-h, only, were performed.Results Ninety patients were enrolled in the study. Compared with those in group B, intraoperative blood loss, drainage volume, total postoperative blood loss, and number of patients requiring allogenic blood transfusion were significantly reduced in group A. There was no significant difference between the incidence of complications in the groups.Conclusions Our topical procedures enable effective and safe reduction of blood loss and the number of patients requiring transfusion in single-stage bilateral osteoarthritic TKA.

The role of CT analyses of the sternal end of the clavicle and the first costal cartilage in age estimation.

The ossification patterns of medial clavicle and the first costal cartilage represent interesting features of the same anatomical region which are accessible for conventional radiographic and computed tomography (CT) examinations in the same field of view. This study encompassed Serbian population and was carried out to examine whether CT analyses of medial clavicle and the first costal cartilage could be successfully applied, either individually or conjointly, in the age assessment. The study was based on CT examinations of thoracic region of 154 patients, aged between 15 and 35 years. Besides radiodensity and stages of epiphyseal cartilage ossification of medial clavicle, the study detected other features that expressed significant correlation with age, such as calculated anterior to posterior cortical thickness ratio, medullar canal diameter, and clavicular shaft diameter. However, although calculated ossified and calcified linear projections' (OCP) stages correlated to age, the distinction between stages was not satisfying. The interaction between the ossification status of medial clavicle and OCP was not significantly influenced by age. The results of our study outlined interesting new age predictors with mutual relationship: acquired radio density of the sternal epiphyseal-metaphyseal region and radio density of the first costal cartilage. Intersex variability was observed in several age-related features: calculated anterior to posterior cortical thickness ratio, diameter of medullar canal, and diameter of the clavicular shaft. Altogether, our study identified several radiological features of the first costal cartilage and medial clavicle that correlated with age and which could be applied as additional guidance for age estimation in each specific case.

Rasche Prototypen-Technik in der präoperativen Planung der totalen Hüft-Arthroplastie mit speziell angefertigten femoralen Komponenten

One of the problems we come across in our practice is related to the patients with very disturbed anatomy structures of the hip joint due to the incompatibilities between standard implants and host bone. These incompatibilities are usually represented by an extreme narrowing of the femoral medullary canal or sometimes by disturbances of the diaphyseal anatomical axis of the femur and are encountered in younger patients who usually require pressfit uncemented implants in order to achieve a normal survivorship of the implant. In these particular cases, customized prosthetic components may represent an alternative, but there are still controversies regarding the biomechanical behavior of these implants compared to the standard components.The use of prototypes for the receiving bone and for the prosthetic implant, respectively, is helpful in the validation process of the optimal model of custom implant by eliminating those designs that cannot be inserted into the medullar canal or those that could injure the receiving bone structure.Prototype design and execution for both the implant and femoral structure by means of rapid prototyping technology represents a major advantage in carrying out the preoperative planning of this type of surgical interventions due to the possibility of preoperative simulation of the insertion of femoral component into the medullar canal.

Enhancement of bony in‐growth to metal implants by combining controlled hydroxyapatite coating and heat treatment

The rate of bony in-growth to heat-treated and controlled hydroxyapatite metal implants made of either titanium alloy (Ti-6Al-4V) or stainless steel (SS) 316L inserted to the medullar canal of the femur in rats was investigated. It was found that while partial coverage of hydroxyapatite (HA) did not cause a significant elevation of their bonding strength when compared with nonheated implants, HA, and heat treatment caused a significant (p < 0.01) elevation of 3.1-fold in the bonding strength of the implants to the host bone. A similar phenomenon to that found for the titanium alloy implants was found to be true for the SS implants as well. It is concluded that the novel approach presented in this article, that is, to heat treat implants as well as controlled partial coating of them by HA, prior to their insertion to host bone, produce an enhancement of bone growth to metal implants greater than utilization of each method alone. Our findings may be used to further enhance bony in-growth to metal implants in several clinical settings, producing avid implants with superior integration capabilities.

Vascularização temporária de membros isquêmicos por meio de shunt arteriomedular: trabalho experimental

CONTEXTO: Os autores idealizaram um shunt temporário entre a artéria femoral e o canal medular de ossos longos para manter a viabilidade dos membros agudamente isquêmicos, enquanto não é possível estabelecer um tratamento definitivo. OBJETIVO: Avaliar a perviedade de shunts temporários arteriomedulares e a perfusão dos membros, durante duas horas em cães de experimentação, que tiveram a artéria femoral ligada. MÉTODOS: Alocaram-se aleatoriamente dois grupos, com três cães no Grupo Controle e seis no Grupo Intervenção. Os controles tiveram a artéria femoral comum direita ligada. O Grupo Intervenção, além da ligadura da artéria, recebeu um shunt. Após duas horas, realizou-se a medida de pH dos membros isquêmicos; avaliação do fluxo arterial por meio de um sonar Doppler; avaliação da coloração do sangramento na extremidade distal do membro e foram retirados em bloco torácico os pulmões para análise anatomopatológica. RESULTADOS: A média do pH do sangue capilar das extremidades do membros no Grupo Controle foi de 6,97 (±0,39); no Grupo Intervenção o pH foi de 7,25 (±0,46), com p&lt;0,001; a coloração do sangue no Grupo Intervenção manteve-se com aspecto rutilante em todos os animais. Os shunts necessitaram, em média, três irrigações com solução salina heparinada para manterem-se pérvios. A avaliação macroscópica e microscópica do tecido pulmonar não evidenciou embolia gordurosa. CONCLUSÃO: O shunt arterio-osteal ou arteriomedular apresentou viabilidade técnica em laboratório.

Unidirectional Porous β-Tricalcium Phosphate Bone Substitute: Examination of Balance between New Bone Formation and Absorption

In the present study, we have newly developed an artificial bone substitute, which is unidirectional porous β-tricalcium phosphate (UDPTCP). The objective of this study was to examine the effects of high and low porosity substitutes on the balance between new bone formation and β-TCP absorption. Materials and MethodsSix male Japanese white rabbits (weight 3.1–3.5 kg, approximately 18– 21 weeks old) were used for this study. Intra-venous injection of pent barbiturate was administered and the both medial and lateral femoral condyle were exposed. A hole of 5 mm diameter was drilled to a depth of 12 mm in the metaphysis, perpendicular to the long axis of the femur. (Figure 1) Figure 1. Operation procedureIn the next step, a cylindrical UDPTCP test piece measuring 4.8 × 11 mm was implanted in the holes. Within the bone substitute, unidirectional pores ranging from 100 to 300 μm in diameter were made. This unique architecture fostered transmission of fluids and cells into the piece. In this case, the test piece was implanted into the bone perpendicular to the long axis of the femur, and the orientation of uni-directional pore was parallel to the long axis of femur. We prepared two different test pieces having low (69%) and high (74%) porosities. Half of the animals were sacrificed at 3 weeks after the operation and the remaining half at 6 weeks. After removal of the femoral condyle, the specimen was fixed in formalin and demineralized. Specimens were obtained from the central axis of the cylindrical piece as well as from the lateral or medial surfaces at a distance of 4 mm from midline. The histological samples were prepared for H&amp;E and TRAP staining. Results and Discussion At 3 weeks interval, woven bone, which was formed along the wall of the substitute, could be observed by H&amp;E staining in both low and high porosity substitutes (Figure 2a, 2b). In addition, there were osteoblast-like cells lining the newly formed bone surface with extensive capillary formation (Figure 3). At 6 weeks, the β-TCP walls had thinned and bone had matured in both the groups (Figure 4a, 4b). However, in the high-porosity group, β-TCP absorption tended to be more prominent (Figure 4). In addition, it was observed that at the center of the piece, β-TCP absorption was more prominent than that in the 4 mm-area obtained from the lateral or medial surfaces. At 3 and 6 weeks interval, activities of osteoclast-like multinuclear cells were seen on the surface of the pore wall as observed by TRAP staining. Figure 2a. Low porosity (69%) Figure 2b. High porosity (74%) Fig.2a and Fig.2b H&amp;E staining (×12.5) after 3 weeks (center of the specimen)Figure 3. Formation of woven bone with osteoblast-like cells lining the low porosity specimen at 3 weeks. (H&amp;E staining ×400) Figure 4a. Low porosity Figure 4b. High porosityFig.4a and Fig. 4b H&amp;E staining at 6 weeks after implantation. In high porosity, dense-pink staining areas are located at peripheral in the field.Figure 5. TRAP-positive multinuclear cells (black arrow) were seen on the wall and in the capillaries.Conclusions The UDPTCP implanted in the medullar canal of the femur was absorbed by multinuclear cells and quickly replaced by the newly formed bone. Our results are consistent with those of other studies using porous β-TCP [1]. In our preparation, porosity had certain effects on the balance between bone formation and β-TCP absorption. Because of the unique architecture of unidirectional pores within the β-TCP specimen as well as easy formation of capillary network and access to osteoclasts may have accelerated absorption of the substitute. UDPTCP is very promising scaffolding material for bone regeneration. However, optimization of the porosity of UDPTCP in accordance with its application site is necessary before its clinical use. Reference[1] Naoki Kondo, Akira Ogose, Kunihiko Tokunaga, Tomoyuki Ito, Katsumitsu Arai, Naoko Kudo, Hikaru Inoue, Hiroyuki Irie, Naoto Endo: Bone formation and resorption of highly purified β-tricalcium phosphate in the rat femoral condyle. Biomaterials 26: 5600-5608, October 2005.