Les complications orthopédiques de l’ostéogenèse imparfaite

Osteogenesis imperfecta is a genetic disease characterized by bone frailty. It is generally caused by an abnormal production of collagen, which is the main fibrous protein of the bone. Collagen is also present in the skin, tendons, the sclera of the eye and dentin. The most frequent manifestation of osteogenesis imperfecta is the occurrence of multiple fractures without major trauma. Severity and timing of the attack varies widely: some patients sustain a significant number of fractures during early childhood which may have a serious impact on growth, while others will have some fractures separated by a few years. In all cases, the bone strength improves in adulthood. The bone fractures cause pain and bone deformities sometimes result in a smaller size. Scoliosis is frequent and associated with painful vertebral collapses. We present a case of osteogenesis imperfecta in a 40-year-old adult and we describe the various orthopaedic complications of the disease, stressing the role of bone scintigraphy in the diagnosis and monitoring of these complications.     

Decellularized tissue and cell-derived extracellular matrices as scaffolds for orthopaedic tissue engineering

The reconstruction of musculoskeletal defects is a constant challenge for orthopaedic surgeons. Musculoskeletal injuries such as fractures, chondral lesions, infections and tumor debulking can often lead to large tissue voids requiring reconstruction with tissue grafts. Autografts are currently the gold standard in orthopaedic tissue reconstruction; however, there is a limit to the amount of tissue that can be harvested before compromising the donor site. Tissue engineering strategies using allogeneic or xenogeneic decellularized bone, cartilage, skeletal muscle, tendon and ligament have emerged as promising potential alternative treatment. The extracellular matrix provides a natural scaffold for cell attachment, proliferation and differentiation. Decellularization of in vitro cell-derived matrices can also enable the generation of autologous constructs from tissue specific cells or progenitor cells. Although decellularized bone tissue is widely used clinically in orthopaedic applications, the exciting potential of decellularized cartilage, skeletal muscle, tendon and ligament cell-derived matrices has only recently begun to be explored for ultimate translation to the orthopaedic clinic.     

Regeneration of the skeleton by recombinant human bone morphogenetic proteins

Recombinant human bone morphogenetic proteins (rhBMPs) have past a long journey in human orthopaedic surgery during the last 15 years. From the first reports of the use of rhBMPs in hostile environments such as critically-sized bone defects, avascular femoral head necrosis, unstable thoracolumbar vertebral fractures, instability between the atlas and axis due to rheumatoid arthritis; over the use for nonunions of long bones and the scaphoid, reconstructive and revision surgeries of the hip, acute fractures, allograft nonunions, congenital pseudarthrosis, and various approaches of lumbar and cervical spine fusions, rhBMPs overgrow to a safe and reliable device in the treatment of open tibial shaft fractures, nonunions of long bone fractures, anterior lumbar interbody fusion and revision posterolateral lumbar fusions. Systematic review of the published literature of rhBMPs is presented.     

Novel technology to provide an enriched therapeutic cell concentrate from bone marrow aspirate

Current strategies to repair fractures rely on orthopaedic surgeons harvesting bone from one area of the body, typically pelvis and transferring it to the fracture site. The amount of tissue available is therefore limited, requiring a second surgical procedure and often causing the patient long term pain. An alternative approach is utilise therapeutic cells contained within bone marrow aspirate during the primary procedure. The number of therapeutic cells within a fresh aspirate is insufficient to provide clinically acceptable bone healing in a timescale that is satisfactory to the surgeon and the patient. Therefore methods to efficiently concentrate bone marrow in the clinical setting are required. Centrifugation is the current method of choice but has limitations in that it requires large capital equipment, servicing and there are potential issues of tissue contamination. We have developed a novel, acoustically‐assisted filtration device that addresses these limitations, delivering a concentrated bone marrow in a point of care, single use, fully disposable, compact device. An additional advantage is that the level of concentration required can be specified by the end user. The resulting bone marrow concentrate has been characterised in terms of cell number, viability and osteogenic potential using flow cytometry and alkaline phosphatase assay. When compared to recent clinical studies using bone marrow to repair non‐union fractures, the findings from our work suggest that the bone marrow concentrate is likely to be highly therapeutic and clinically efficacious as a bone fracture repair strategy. A product concept for use in the clinical setting is presented. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010     

Transplantability and therapeutic effects of bone marrow-derived mesenchymal cells in children with osteogenesis imperfecta

In principle, transplantation of mesenchymal progenitor cells would attenuate or possibly correct genetic disorders of bone, cartilage and muscle, but clinical support for this concept is lacking. Here we describe the initial results of allogeneic bone marrow transplantation in three children with osteogenesis imperfecta, a genetic disorder in which osteoblasts produce defective type I collagen, leading to osteopenia, multiple fractures, severe bony deformities and considerably shortened stature. Three months after osteoblast engraftment (1.5-2.0% donor cells), representative specimens of trabecular bone showed histologic changes indicative of new dense bone formation. All patients had increases in total body bone mineral content ranging from 21 to 29 grams (median, 28), compared with predicted values of 0 to 4 grams (median, 0) for healthy children with similar changes in weight. These improvements were associated with increases in growth velocity and reduced frequencies of bone fracture. Thus, allogeneic bone marrow transplantation can lead to engraftment of functional mesenchymal progenitor cells, indicating the feasibility of this strategy in the treatment of osteogenesis imperfecta and perhaps other mesenchymal stem cell disorders as well.     

Fibular and metatarsal osteosynthesis in a southern brown howler monkey (Alouatta guariba clamitans)

Here we describe a successful surgical management of a distal fibular fracture combined with a tarsocrural luxation and multiple metatarsal fractures in the left foot of a southern brown howler monkey (Alouatta guariba clamitans). We achieved satisfactory outcome by applying intramedullary pinning for each of the bone fractures and closed reduction of joint luxation—kept in place only by bone alignment, without further ligament reconstruction. Bone healing occurred uneventfully within eight weeks and the monkey's foot regained its normal function. Therefore, we could properly release the patient back into the wild.     

Metabolic bone disease: atypical femoral fractures

Since 2005 reports have been published describing unusual femoral shaft fractures primarily in postmenopausal women treated for prolonged periods with a bisphosphonate drug for osteoporosis. In some patients pain develops in the femur prior to a completed fracture. Bilateral fractures have occurred in some patients. It is unclear whether oversuppression of bone cell activity is a major factor in the pathogenesis of the fractures, or whether these are a rare manifestation of the underlying bone disease. Such fractures do occur in other metabolic bone disorders in which there are marked abnormalities of bone structure.     

Fresh frozen homologous bone in oral surgery: case reports

Intraoral bone defects may be treated using autologous grafts, homologous grafts, heterologous grafts or synthetic products. Autologous bone is now considered the gold standard for bone grafting procedures. Homologous fresh frozen bone, provided by bone banks, is frequently utilized by orthopaedic surgeons because it is considered a safe material from immunological and viral points of view.In the cases reported here, homologous bone was used to repair some osseous defects without changing the surgical protocol utilized for autologous bone procedures. The main advantages of this strategy are low morbidity, shorter surgical times, more comfort and less risk of infection for the patient as well as the greater availability of bone.     

神阙穴帖敷治疗骨科骨折患者术后便秘的疗效观察

目的探讨大黄水蜜贴敷"神阙"穴对骨折术后便秘的治疗效果。方法选取我院骨科骨折术后发生便秘的患者100例,随机分成治疗组和对照组各50例。对照组采用传统的治疗方法,即在骨科常规护理措施上指导患者多饮水,多进食水果、蔬菜,必要时给予缓泻药或开塞露纳肛。治疗组在对照组的基础上加用大黄水蜜贴敷"神阙"穴治疗,并对两组患者的便秘情况和相关症状进行比较。结果治疗组的治疗有效率为90%,对照组为60%,两组比较差异有统计学意义(P0.05);观察组发生便秘的相关症状少于对照组,差异有统计学意义(P0.05)。结论大黄水蜜贴敷"神阙"穴治疗骨科骨折术后便秘的疗效显著,值得临床推广应用。     

Stéroides sexuels et ostéoporose chez l'homme

Several epidemiological studies have shown that about 25 per cent of hip fractures and 20 per cent of symptomatic vertebral fractures occur in men. The lifetime risk of hip fracture was estimated to be about 6 to 8 per cent and the risk of any osteoporotic fracture was estimated to be about 18 per cent in 50-year-old white men. In about 60% of cases in men, bone loss is secondary to several pathological conditions, such as long-term steroid therapy, severe hypogonadism, smoking or alcohol abuse or gastrointestinal disorders. In 40% of cases, osteoporosis is primary or idiopathic in men between the ages of 40 and 60 years. Genetic factors, a defect of boneforming cells or abnormal serum levels of bioavailable sex steroids could explain bone loss and fragility fractures in these men. It has been shown that hypogonadism is associated with a marked increase in bone remodelling and particularly in bone resorption with a dramatic loss in trabecular bone. It is now known that testosterone is partly transformed into estradiol by aromatase. Testosterone may therefore act on bone in two ways: it directly stimulates bone formation and estradiol regulates bone remodelling and inhibits bone resorption. Finally, in men over the age of 60 without hypogonadism, it has been shown that bone mineral density and fracture risk were better correlated with serum levels of bioavailable estradiol and Sex Hormone Binding Globulin than with serum testosterone levels.     

Reductive stress on life span extension in C. elegans

Background

Induction programme for trainee doctors in the UK generally do not focus on the surgical aspects of their jobs. In this context we decided to conduct a telephonic survey among the hospitals belonging to three orthopaedic training regions in the UK from the point of view of the diversity of instrumentations and implants used for index procedures.

Results

We chose four index trauma & orthopaedic procedures (Total hip replacement, total knee replacement, intramedullary nailing and external fixator systems for long bone fractures). A telephonic survey was done in six NHS trust hospitals which were part of an orthopaedic training rotation (2 from England, 2 from Wales and 2 from Scotland). In total there were 39 different instrumentation systems for these 4 index procedures in the 6 trusts (see table 1). These comprise 12 Total hip replacement (THR) systems, 14 total knee replacement (TKR) systems, 9 intra-medullary nailing systems, and 4 external fixator systems. The number of different systems for each trust ranged from 7 to 19. There is a vast array of implants and instrumentation systems in each trust, as highlighted by our survey. The surgical tools are not the same in each hospitals. This situation is more complicated when trainees move to new hospitals as part of training rotations.

Toward CT-based facial fracture treatment

Facial fractures have formerly been classified solely by anatomic location. CT scans now identify the exact fracture pattern in a specific area. Fracture patterns are classified as low, middle, or high energy, defined solely by the pattern of segmentation and displacement in the CT scan. Exposure and fixation relate directly to the fracture pattern for each anatomic area of the face, including frontal bone, frontal sinus, zygoma, nose, nasoethmoidal-orbital region, midface, and mandible. Fractures with little comminution and displacement were accompanied by subtle symptoms and required simple treatment; middle-energy injuries were treated by standard surgical approaches and rigid fixation. Highly comminuted fractures were accompanied by dramatic instability and marked alterations in facial architecture; only multiple surgical approaches to fully visualize the "buttress" system provided alignment and fixation. Classification of facial fractures by (1) anatomic location and (2) pattern of comminution and displacement define refined guidelines for exposure and fixation.     

Therapeutic potentials and modulatory mechanisms of fatty acids in bone

Bone metabolism is a lifelong process that includes bone formation and resorption. Osteoblasts and osteoclasts are the predominant cell types associated with bone metabolism, which is facilitated by other cells such as bone marrow mesenchymal stem cells (BMMSCs), osteocytes and chondrocytes. As an important component in our daily diet, fatty acids are mainly categorized as long‐chain fatty acids including polyunsaturated fatty acids (LCPUFAs), monounsaturated fatty acids (LCMUFAs), saturated fatty acids (LCSFAs), medium‐/short‐chain fatty acids (MCFAs/SCFAs) as well as their metabolites. Fatty acids are closely associated with bone metabolism and associated bone disorders. In this review, we summarized the important roles and potential therapeutic implications of fatty acids in multiple bone disorders, reviewed the diverse range of critical effects displayed by fatty acids on bone metabolism, and elucidated their modulatory roles and mechanisms on specific bone cell types. The evidence supporting close implications of fatty acids in bone metabolism and disorders suggests fatty acids as potential therapeutic and nutritional agents for the treatment and prevention of metabolic bone diseases.     

Biomechanical studies and finite element analysis of a bone-implant interface]

In the present study, the fixation system of a femoral medullary nail connection was investigated. In surgical treatment of fractured femurs, the fracture is bridged by a medullary nail that is fixed by interlocking screws in the bone. Bone failure around these screws is the most common complication associated with the treatment of fractures of osteoporotic bone. The present study analyses the stresses present in the region of the implant/bone system. Three-dimensional finite element models were generated, a nonlinear structure analysis performed, and the stresses at material interfaces investigated. The highest concentration of stresses is to be found in the middle of the interlocking screws and the holes drilled in the bone. This is in agreement with the results of experimental investigations.     

Modeling Staphylococcus epidermidis-Induced Non-Unions: Subclinical and Clinical Evidence in Rats

S. epidermidis is one of the leading causes of orthopaedic infections associated with biofilm formation on implant devices. Open fractures are at risk of S. epidermidis transcutaneous contamination leading to higher non-union development compared to closed fractures. Although the role of infection in delaying fracture healing is well recognized, no in vivo models investigated the impact of subclinical low-grade infections on bone repair and non-union. We hypothesized that the non-union rate is directly related to the load of this commonly retrieved pathogen and that a low-grade contamination delays the fracture healing without clinically detectable infection. Rat femurs were osteotomized and stabilized with plates. Fractures were infected with a characterized clinical-derived methicillin-resistant S. epidermidis (10³, 10⁵, 10⁸ colony forming units) and compared to uninfected controls. After 56 days, bone healing and osteomyelitis were clinically assessed and further evaluated by micro-CT, microbiological and histological analyses. The biofilm formation was visualized by scanning electron microscopy. The control group showed no signs of infection and a complete bone healing. The 10³ group displayed variable response to infection with a 67% of altered bone healing and positive bacterial cultures, despite no clinical signs of infection present. The 10⁵ and 10⁸ groups showed severe signs of osteomyelitis and a non-union rate of 83–100%, respectively. The cortical bone reaction related to the periosteal elevation in the control group and the metal scattering detected by micro-CT represented limitations of this study. Our model showed that an intra-operative low-grade S. epidermidis contamination might prevent the bone healing, even in the absence of infectious signs. Our findings also pointed out a dose-dependent effect between the S. epidermidis inoculum and non-union rate. This pilot study identifies a relevant preclinical model to assess the role of subclinical infections in orthopaedic and trauma surgery and to test specifically designed diagnostic, prevention and therapeutic strategies.     

Accurate,firm stabilization using external pins: a proposal for closed reduction of unfavorable nasal bone fractures and their simple classification

Nasal bone fractures are the most common among facial fractures and are the third most common fractures in the human frame. Although many forms of treatment have been introduced, controversy regarding the optimal treatment still remains. Nasal bone fractures are complex, with significantly varying types that are often undermanaged in closed reduction procedures. The authors' experiences with nasal bone fractures have shown that the baseline for surgical intervention depends on the type of fracture and the method of maintenance after reduction, both of which have considerable impact on the final result. Therefore, it is very important and challenging to determine the proper method of reduction and maintenance. The periosteal covering plays an important role in the splinting action after closed reduction, but sagging, depression, and instability remain major complications in some cases. The authors devised a new method of accurate, firm stabilization of the fractured nasal bone by using external pins in those unfavorable fractures determined radiologically to gain optimal reduction and fixation. In the present study, fractures were grouped into favorable and unfavorable fractures, the latter being those that remained unstable or impacted even after reduction and thus needed open reduction. Unfavorable fractures were divided into four subclasses according to radiologic findings: (1) type I (frontal), including chip or tip fractures, which often depress the upper lateral cartilage and tend to sag after reduction; (2) type II (lateral), or laterally depressed segmental fractures with a lateral shift of the arch in fragments or as a unit; (3) type III (mixed), or type II with septal involvement; and (4) type IV (complex), including open or multiple comminuted fractures. After an initial evaluation to determine the fracture type, closed reduction and external fixation were performed for types I, II, and III fractures and open reduction was performed for type IV fractures 5 to 7 days after the fracture. Closed reduction with the use of external pins was done in eight cases: type I (two), type II (four), and type III (two). The mean age of the patients was 27.8 years, and the average follow-up period was 11.7 months. Functional and aesthetic results were satisfactory. This new method for support and fixation is an alternative to the conventional closed reduction and a promising way to prevent secondary deformity.     

Orthopaedic manifestations of sickle-cell disease

Sickle-cell disease is a well-recognized clinical entity. The pathophysiology of this hemoglobinopathy has been described in detail by numerous investigators since the first case report appeared in 1910. Orthopaedic manifestations of sickle-cell disease account for much of the morbidity associated with this disorder, including pain, osteonecrosis, arthritis, and sepsis. Effective management of these bone and joint sequelae reflect accurate diagnosis, understanding of this disorder's pathophysiology, and knowledge of available medical and surgical treatment alternatives. In this review, the authors summarize the major orthopaedic manifestations of sickle-cell disease with special emphasis placed upon osteonecrosis and osteomyelitis, since these conditions are the most disabling and serious complications in patients with sickle-cell disease.     

OPG/RANKL: role and therapeutic target in osteoporosis

Given the increasing risk of fractures with aging in western countries, there is a need for the development of safe and efficient anti-osteoporotic drugs for the prevention and treatment of osteoporosis. Recent studies have provided evidence for an essential role of RANKL (Receptor Activator of Nuclear Factor-kappa B Ligand) and its decoy receptor osteoprotegerin in the control of osteoclast differentiation and survival. Post-menopausal osteoporosis results from an imbalance between resorption and formation associated with decreased OPG/RANKL. Targeting the OPG/RANKL system may therefore have a beneficial impact in osteoporosis. Accordingly, the development of novel strategies targeting OPG/RANKL using anti-RANKL or therapeutic intervention proved to be efficient to reduce bone resorption and to prevent bone loss in postmenopausal osteoporosis. This opens the way for novel therapeutic strategies for correcting bone metabolism in various pathologic disorders characterized by increased bone remodelling and bone loss.     

Prospective randomised study of an orthopaedic geriatric inpatient service.

A randomised controlled trial of two management regimens was carried out in women patients over 65 years of age with hip fractures. Ninety seven patients were admitted to a designated orthopaedic geriatric unit and 125 to orthopaedic wards. No difference was observed in mortality, length of stay, or placement of patients between the two groups. More medical conditions were recognised and treated in patients in the orthopaedic geriatric unit group. It is concluded that designated orthopaedic geriatric units can provide medical care to these patients and should be administered without additional cost.