Biomedical subjects

V Alt

Publications and source records attributed to V Alt.

17 recordsLinked to original sources

PubMed2006

[Cost-benefit analysis of the use of rhBMP-2 in open tibial fractures: savings from a health insurer's perspective].

BACKGROUND AND PURPOSE: The purpose of the current study was to evaluate savings from the use of recombinant human bone morphogenetic protein-2 (rhBMP-2) in open tibia fractures by faster fracture healing and reduction of secondary treatment costs from a health insurance perspective for Germany and to compare them to the upfront price of 2900 EUR of rhBMP-2. METHODS: Raw data from a previously published study (BESTT study) were used to conduct an economic calculation for secondary treatment costs for each patient from the standard care group and the 1.5 mg/ml rhBMP-2 group based on G-DRG 2005 prices from a health insurer's perspective for an observation period of 1 year for Germany. RESULTS: The use of rhBMP-2 leads to savings of 5697 EUR and 3183 EUR per patient for Gustilo-Anderson grade IIIB and all grade IIIA and B injuries, respectively. These savings offset the upfront price of 2900 EUR of rhBMP-2 and, therefore, net savings of 2797 EUR and 283 EUR for grade IIIB and all grade IIIA and B injuries can be achieved, respectively. These savings are mainly due to reduced sickness payments because of faster fracture healing in the rhBMP-2 group. CONCLUSIONS: The current study shows that the use of rhBMP-2 in Gustilo-Anderson grade IIIA and B open fractures leads--besides the better medical outcome for patients as shown previously in the BESTT study--to net savings from a health insurer's perspective.

Bone Morphogenetic Protein 2↗

PubMed2006

[School accidents--an epidemiological assessment of injury types and treatment effort].

Children and adolescents spend up to 50% of their time at school. The purpose of this study was to assess injury patterns with their treatment of school accidents in a Trauma Service of a German University Hospital and to compare these data to the literature. All school accidents from 01.07.1999 to 30.06.2004 were statistically analysed in a retrospective manner by chart review. There were 1399 school accidents treated in our department. Average age of the injured children was 11.8 years with a boy:girl ratio of 3:2. Almost 40% of the injuries occurred during school sport. The most frequently injured region was the upper extremity including the hand (36.8%). Distortion and contusion were the most frequent diagnoses of all injuries. 16% of the cases had to be treated surgically and/or under general anaesthesia and also a total of 16% of the patients had to be admitted to the hospital. It can be concluded for school facilities that special attention has to be paid during school sports activity and breaks because they account for most accidents. Traffic education may reduce severe injuries. For diagnosis and treatment of school accidents specific knowledge of the growing longbones of the upper extremity and the hand is important.

Accidents↗

PubMed2006

Economic considerations for the use of recombinant human bone morphogenetic protein-2 in open tibial fractures in Europe: the German model.

The addition of recombinant human bone morphogenetic protein (rhBMP-2) to the standard of care, consisting of soft tissue management and intramedullary nailing, in the BMP-2 Evaluation in Surgery for Tibial Trauma (BESTT) study led to a significantly better outcome for the patient. Reductions in fracture healing time, secondary interventions for delayed fracture healing and infection rates were observed with 1.50 mg/mL rhBMP-2 compared with the standard of care alone. In Germany the approximate cost of applying one dose of recombinant human bone morphogenetic protein-2 (rhBMP-2) to an open tibial fracture is euro2970. The current German-Diagnosis-Related Group reimbursement system provides one flat rate per hospital stay or treatment case, and does not take into account the costs of rhBMP-2 application. Therefore there is no reimbursement for the price of rhBMP-2 for hospitals by health insurance companies. However, the above mentioned improvements in medical outcome could lead to important savings for health care systems, particularly for health insurance companies. A sound economic model to assess the cost-effectiveness and budget impact of rhBMP-2 is required. Using medical data from the BESTT study the differences in fracture healing time, in reduction of secondary interventions for fracture healing and infection treatment can be transferred into economic savings. It is anticipated that the overall savings that can be achieved by rhBMP-2 treatment in open tibia fractures, offset the upfront price of rhBMP-2 and lead to net savings for health insurance companies.

Bone Morphogenetic Protein 2↗

PubMed2005

Regulation of mesenchymal stem cell and chondrocyte differentiation by MIA.

Melanoma inhibitory activity (MIA), also referred to as cartilage-derived retinoic acid-sensitive protein (CD-RAP), an 11-kDa secreted protein, is mainly expressed in cartilaginous tissue during embryogenesis and adulthood. Currently, the function of MIA in cartilage tissue is not understood. Here, we describe that MIA acts as a chemotactic factor on the mesenchymal stem cell line C3H10T1/2, stimulating cell migration significantly at concentrations from 0.24 to 240 ng/ml, while inhibiting cell migration at higher doses of 2.4 microg/ml. When analyzing the role of MIA during differentiation processes, we show that MIA by itself is not capable to induce the differentiation of murine or human mesenchymal stem cells. However, MIA influences the action of bone morphogenetic protein (BMP)-2 and transforming growth factor (TGF)-beta 3 during mesenchymal stem cell differentiation, supporting the chondrogenic phenotype while inhibiting osteogenic differentiation. Quantitative RT-PCR analysis revealed the up-regulation of the cartilage markers MIA, collagen type II and aggrecan in human mesenchymal stem cell (HMSC) cultures differentiated in the presence of MIA and TGF-beta 3 or BMP-2 when compared to HMSC cultures differentiated in the presence of TGF-beta 3 or BMP-2 alone. Further, MIA down-regulates gene expression of osteopontin and osteocalcin in BMP-2 treated HMSC cultures inhibiting the osteogenic potential of BMP-2. In the case of human primary chondrocytes MIA stimulates extracellular matrix deposition, increasing the glycosaminoglycan content. Therefore, we postulate that MIA is an important regulator during chondrogenic differentiation and maintenance of cartilage.

Adult↗

PubMed2005

The arteries of the humeral head and their relevance in fracture treatment.

Bone vascularisation has gained increased interest in relation to the blood supply of bone fragments during treatment of fractures. In the current study the pattern of vascular supply of the proximal humerus was studied in six cadavers by the corrosion technique. Furthermore, the effect of fractures on the vascular supply was also investigated. In all preparations the intraosseous arteries of the humeral head arose from the circumflex arteries, which surrounded the humerus and dispatched branches towards the proximal end. The main vessel was the branch of the anterior circumflex artery, penetrating the major tubercle in six of six cases. Due to the intraosseous arch shape of this vessel it is referred to as the arcuate artery. Besides other smaller vessels, there was also a vascular network arising from the posterior circumflex artery. Their branches penetrated medially at the cartilage bone interface in five of six preparations. The medial bone arteries appear to gain distinctive importance in humeral head fractures by their impact on the vascularisation of the fracture fragments. After disruption of the arterial supply from the arcuate artery, the vascularisation of the head fragments is most likely ensured by this group of vessels. Therefore, necessary repositioning manoeuvres during open reduction of the fracture should be conducted with care in order to preserve these arteries.

Aged↗

PubMed2005

Plasma transglutaminase factor XIII induces microvessel ingrowth into biodegradable hydroxyapatite implants in rats.

Coagulation factor XIII is a member of the transglutaminase-family. Transgluaminases cross-link either fibrin monomers in blood coagulation or extracellular proteins in extracellular matrix formation. In early stages of bone healing migration and proliferation of endothelial cells lead to formation of new vessels. The aim of this study was to investigate the angiogenetic activity of plasma factor XIII in bone defects filled with nanoparticulate hydroxyapatite paste. A critical size defect was created in the tibial head of rats which was not filled in group I. In group II the defect was filled with hydroxyapatite paste, and in group III with hydroxyapatite paste enriched with factor XIII. Ten days after surgery angiogenesis in the defects was assessed using immunohistochemistry and confocal laser scanning microscopy. Ac16 antibody was used to detect activation of factor XIII into factor XIIIA. In defects without biomaterial (group I) vessel-rich connective tissue and diffuse distribution of capillaries was observed. In defects filled with pure hydroxyapatite (group II) formation of capillaries was limited to the host bone-hydroxyapatite interface. In contrast, addition of plasma factor XIII to hydroxyapatite (group III) stimulated formation of vessels within the biomaterial. The current study reveals that factor XIII can improve angiogenesis in hydroxyapatite.

Absorbable Implants↗

PubMed2005

[Covering of soft tissue defects of the lower leg with adipo-facial flaps].

AIM OF THE STUDY: Soft tissue covering on the lower leg is a difficult challenge. A plastic surgical method for covering of these soft tissue defects is presented. PATIENTS AND METHODS: From May 1997 until May 2003 36 patients were treated using neurovascular flaps. Above the sural or the saphenous nerve an adipo-facial flap is dissected, rotated into the defect and fixed without tension. Wound closure of the donor-site defect is done primarily or by mesh-graft. RESULTS: In 35 cases the flap healed without functional impairment. Primary healing was achieved in 30 patients. In 5 cases partial loss of the skin island was registered, whereby subcutaneous tissue remained vital. Revision by mesh-graft transplantation led to successful healing in these patients. In only one patient necrosis of the flap was seen. CONCLUSION: Neurovascular flaps usually result in reliable and complete healing of soft tissue defects of the lower extremity.

Adolescent↗

PubMed2005

[The arteries of the humerus and their relevance in fracture treatment].

BACKGROUND: The purpose of the current work was to study the arterial blood supply of the humerus to evaluate impairments of the blood supply after humeral fractures and different methods of fracture treatment. METHODS: Arterial blood supply of the humerus was studied by corrosion injection technique in 6 cadaver preparations and is compared with the existing literature. RESULTS: Humeral head arteries originate from the circumflex humeral arteries. The major vessel enters the greater tubercle. Another group of vessels accesses the head from medially. The nutrient artery for the shaft enters into the medial third of the shaft. At the distal humerus there are multiple anastomoses with penetrating branches into both condyles and proximal to the radial, coronoid, and olecranon fossae. CONCLUSIONS: Fragments of a proximal humeral fracture usually have an independent blood supply. The medial vessels to the head gain high importance in fractures of the anatomical neck. The nutrient artery lies regularly medial to the humeral mid-shaft and is at risk at open reduction of this region. The abundant vessels at the entire distal humerus ensure sufficient vascularization of the fragments after fracture.

Arteries↗

PubMed2004

[Difficulties involved in the Hoffa fractures].

To study the outcome in Hoffa fractures regarding the type of fracture, concomitant injuries, and different treatments. From January 1996 until December 2002, 7 Hoffa fractures (6 patients) from a total of 79 distal femoral fractures were treated in the Department of Trauma Surgery, University Hospital of Giessen. The results were evaluated by Neer's score. For the evaluation of postoperative vascularization of the distal femur, clinical and radiological findings were compared with anatomical studies of the bone arteries by corrosion preparations. Fracture consolidation was seen in all cases. Patients with an isolated Hoffa fracture achieved a score of 89.0 (82-97) according to Neer. One patient suffering initially from nonunion achieved 68 points after bone union. One polytraumatized patient with bilateral Hoffa fracture achieved a satisfying result (score value of 72) and a bad result (score value of 38). Multiple small nutrient arteries of the distal femur originate from the "rete articulare genus." They can be expected to ensure the arterial blood supply. Hoffa fracture is a very rare injury. In our patients, careful surgical treatment with open reduction and safe screw fixation yielded good to very good results.

Adult↗

PubMed2004

[Nanoparticulate silver. A new antimicrobial substance for bone cement].

BACKGROUND: Multiresistant bacteria have become an important problem in prosthetic joint infections. Their frequent resistance against gentamicin, which is commonly used in antibiotic-loaded bone cements, makes a new prophylaxis necessary. METHODS: PMMA-cement was loaded with 1% nanoparticulate silver and its antibacterial activity tested in vitro against gentamicin-resistant MRSE and MRSA strains as well as being compared to the activity of plain and gentamicin-loaded bone cements. A quantitative elution testing was also done to study the potentially cytotoxic effects of NanoSilver cement. RESULTS: Unloaded and PMMA-cement loaded with 2% gentamicin did not exhibit any antibacterial activity against MRSE and MRSA. At 1%, NanoSilver cement completely inhibited the proliferation of MRSA and MRSE. NanoSilver bone cement did not show any significant differences compared to the non-toxic control group. CONCLUSIONS: If these promising in vitro results can be confirmed in vivo, NanoSilver bone cement may be of considerable value in total joint arthroplasty.

Animals↗

PubMed2004

Expression of EDA+ and EDB+ fibronectin splice variants in bone.

The extracellular matrix component fibronectin (fn) has fundamental functions in cell attachment, differentiation, proliferation, and migration. Isoforms of cellular fibronectin, named EDA+ fibronectin or embryonal EDB+ fibronectin, are generated by alternative splicing of its mRNA precursors. Little is known about the expression of EDA+ and EDB+ fibronectin splice variants in human bone. The aim of this study was to investigate the expression pattern of fibronectin splice variants in bone cell lines and in different human bone tissue samples (mature bone, early stages of fracture healing, hypotrophic nonunion, osteosarcoma). Analysis was done by immunostaining with recombinant and monoclonal antibodies, qualitative RT-PCR and LightCycler-based real-time quantitative RT-PCR assay. In osteoblast and osteosarcoma cell lines, abundant expression of EDA+ and EDB+ fibronectin was found in immunocytochemistry. High transcription levels of both splice variants mRNA were seen in quantitative RT-PCR in osteosarcoma cell lines. In mature bone, EDA+ and EDB+ were not detectable in immunohistochemistry. Transcription of mRNA in both splice variants was absent in these samples. Early stages of fracture healing and osteosarcoma cell samples exhibited extensive staining for EDA+ and EDB+ fibronectin, and high mRNA levels were found. Both osteosarcoma and bone fracture healing tissue expressed high mRNA levels of the fibronectin splice variants independent of benign or malignant behavior. Low level of EDA+ fibronectin mRNA transcription and focal immunohistochemical staining of EDA+ fibronectin was found in hypotrophic nonunions, whereas EDB+ fibronectin was not detected by immunohistochemistry and qualitative or quantitative PCR. EDA+ fibronectin was found in granulation tissue-forming processes in bone independent from bone-forming activity. EDB+ fibronectin was seen only in high-turnover new osteoid-forming processes like early stages of fracture healing and osteosarcoma and was absent in low-turnover processes like mature bone and hypotrophic nonunion. Both EDA+ and EDB+ fibronectin mark active processes in bone without differentiation between malignant or benign activity. In conclusion, EDA+ and EDB+ fibronectin splice variants are strong markers for active fibrogenetic and osteoid-forming processes in human bones.

Adolescent↗

PubMed2004

Dorsal transscaphoid-transtriquetral perilunate dislocation in pseudarthrosis of the scaphoid.

A patient reported that he sustained a minor fall on the outstretched hand in hyperextension, pronation, and in ulnar deviation. Initial radiographs suggested dorsal transscaphoid-transtriquetral perilunate dislocation. Traditionally, however, this injury is the result of a high-energy impact. A CT scan obtained after closed reduction of the dislocation revealed not only a fresh fracture of the triquetrum but also two corticalized fragments of the scaphoid. A former major fall on this hand and a normal scaphoid of the other hand made pseudarthrosis more likely than scaphoid bipartition. Arthrography revealed intact lunotriquetral and scapholunate ligaments, precluding the possibility of preexisting ligamentous instability. Pseudarthrosis of the scaphoid with a loss of scaphoid function as a mechanical tie-rod of the carpus is most likely responsible for this complex injury. This is the first clinical study that shows that single scaphoid discontinuity without preexisting ligamentous carpal instability may lead to complex perilunar dislocation in minor trauma.

Adult↗

PubMed2002

[The BEHAC nail--a new intramedullary implant for managing 2-stage fractures of the humerus].

The BEHAC-nail is a new implant for the treatment of complex humeral fractures, particularly for segmental fractures. It is an elastic intramedullary implant that is inserted retrograde into the distal humerus. The special feature of this nail is its proximal "loop design" which reduces the implant penetration at the proximal fixation site in the subchondral area of the humeral head in comparison to implants with tips such as Rush pins or Hackethal's nails. Thus, the risk of nail migration and perforation of the humeral head is less with the BEHAC-nail than with other nails. Another advantage of the "loop design" is that the humeral head fragment can be fixed adequately. Even short proximal fragments can be stabilized with this design. In contrast a short humeral head fragment cannot be held with implants like the UHN, HVN or Seidel's nail. The BEHAC-nail is a useful implant for segmental fractures of the humerus.

Equipment Design↗

PubMed2002

[Intraligamentous suture of a scapholunar ligament lesion in a 9-year-old child].

Scapholunate dissociation is a well-known injury in adult patients. In pediatric patients, repair of this injury in the skeletally immature carpus has been previously reported. However, in none of these case studies is single ligamentous suture performed. We report a case of scapholunate dissociation in a 9-year-old boy after an initial Salter I injury of the distal radius. After 6 weeks of wrist immobilization, arthroscopy was performed due to persisting pain over the scapholunate gap, a positive Watson sign, and limited range of motion. This arthroscopy revealed intraligamentous rupture of the scapholunate ligament. Suture repair of the scapholunate ligament was performed. The suture was protected by a temporary K-wire arthrodesis for 8 weeks. One year after removal of the K-wire, the patient is completely free of symptoms and resumes all sport activities.

Arthroscopy↗

PubMed2001

Knee fusion--a new technique using an old Belgian surgical approach and a new intramedullary nail.

Knee arthrodesis is a useful procedure in difficult cases such as failed total knee arthroplasty, severe articular trauma, bone tumors, and infected knee joints. The most common techniques for knee fusion include external fixation and intramedullary nailing. Küntscher's nail is driven antegrade from the intertrochanteric region into the knee. We describe a new technique for knee arthrodesis using a new intramedullary nail and an old Belgian surgical approach to the knee joint published by Lambotte in 1913. This approach provides excellent exposure for the implantation of the nail by osteotomizing the patella vertically. The nail is implanted using HeyGroves method, whereby the nail is inserted retrograde into the femur and pulled distally anterograde into the tibia. We now use this technique as our standard procedure for knee fusion.

Arthrodesis↗

PubMed1999

Bone grafting from the proximal tibia.

OBJECTIVE: A retrospective study was undertaken to analyze the results of proximal tibial bone grafts with immediate postoperative weight bearing. METHODS: Over a 2-year period, 54 patients underwent bone grafting harvested from the proximal tibia. Postoperatively patients were allowed to bear weight as tolerated on the donor site. Mean follow-up was 26.4 weeks, with a range of 6 to 80 weeks. Indications for bone grafting were fresh fractures with primary grafting and nonunions. RESULTS: The overall complication rate was 1.9%, with one patient suffering a local hematoma. No major complications such as fracture, sensory deficit, or wound infection were observed. Immediate postoperative weight bearing did not have any deleterious effects. Higher complication rates for iliac graft sites have been reported. The amount of bone that can be harvested is usually more than adequate. CONCLUSION: Complication rates are low without significant patient morbidity. Most importantly, the patients may start weight bearing immediately after surgery.

Adult↗

PubMedDate not supplied

[Health-economic considerations for the use of BMP-2 for spinal surgery in Germany].

INTRODUCTION: BMP-2 can replace autogenous bone grafting in lumbar one-level anterior lumbar interbody fusions (ALIF). The current G-DRG system does not reimburse the upfront price of 2,970 euro per BMP-2 application for hospitals in Germany. The purpose of the current study was to create a health economic model to evaluate the financial savings for health care providers (hospitals) and health care payers (health care insurance) that can be achieved by the use of BMP-2 in spine surgery. METHODS: A previously published pooled data analysis was used in which BMP-2 showed significant improvements in the treatment after ALIF surgery compared to autogenous bone grafting, including earlier return to work time and reduced revision rates. These medical findings were transformed into economic data based on the regulations of the German health system of 2005. RESULTS: The significantly shorter return to work time under BMP-2 treatment generates important financial savings for health care insurances offsetting the upfront prize of 2,970 euro for BMP-2. Savings for hospitals are mainly related to shorter surgery time due to the absence of the bone grafting procedure and faster discharge of the patient. CONCLUSIONS: The combination of improved medical outcome by BMP-2 treatment for the patient and net savings for the entire health care system in Germany represents a "dominant" strategy from a health economic perspective. This implicates that BMP-2 in ALIF procedures is to be recommended from a health economic point of view for the German health care system.

Bone Morphogenetic Protein 2↗