Search results for " Bone"
showing 10 items of 933 documents
Vergleich radiologischer Verfahren zur präoperativen Beurteilung der Verankerungsfestigkeit von Wirbelsäulenimplantaten
1997
PURPOSE To compare three techniques with regards to their ability to estimate pull out strength of spinal fusion hardware. MATERIAL AND METHODS VDS-screw fixation strength in 50 human cadaveric vertebral bodies was approximated by means of pull out force measurement. Bone quality was assessed by Dual X-ray Absorptiometry (DXA). Quantitative Computed Tomography (QCT) and T2*-relaxation time. For each of these techniques, correlation with axial pull out force strength was investigated. RESULTS Highest correlation was found for cancellous bone density measured by QCT (r = 0.72; p < 0.001). Immediately followed by DXA (r = 0.70; p < 0.001), which involves all bone components. Inverted T2*-relax…
Unusual manifestation of an osteoid osteoma of the capitate.
1999
A case of osteoid osteoma of the capitate in a 29-year-old male is reported. The patient suffered from unspecific clinical findings and a 3-year history of uncharacteristic wrist pain. Conventional radiographs of the wrist revealed a circumscribed sclerosis in the proximal part of the capitate bone beside a diffuse demineralisation of the carpal bones. Magnetic resonance imaging demonstrated a circumscribed, tumorous lesion with marked enhancement after IV administration of contrast agent and a highly calcified nidus, which was sharply demarcated by a small rim of granulation tissue from the surrounding spongious bone. Based on MRI findings, the diagnosis of an osteoid osteoma was establish…
New Modalities in Knee Osteoarthritis Treatment Using Autologous Bone Marrow-Derived Mononuclear Cells
2018
Abstract The clinical effects on knee osteoarthritis (OA) symptoms and tissue structure were evaluated after bone marrow-derived mononuclear cell intraarticular injection. A group of 32 patients with 34 knee joints in stage II–III osteoarthritis were treated by intraarticular injection of mononuclear cell suspension. Clinical results were obtained by KOOS (Knee Osteoarthritis Outcome Score) and KSS (Knee Society Score) scores during a 12 months follow-up period. Radiological evaluation was performed using magnetic resonance imaging. A comparison with a control group of 28 patients treated with routinely used three hyaluronic acid intra-articular injections was made. No adverse effects were …
COL1A1 Sp1 polymorphism associates with bone density in early puberty.
2006
Optimal acquisition of bone mass in puberty is a key determinant of the lifetime risk of osteoporosis and has a strong genetic basis. We investigated the relationship between the COL1A1 Sp1 polymorphism and BMD in early puberty, and how the genotypes relate to bone size and geometry as well as bone turnover and material properties in 247 10- to 13-year-old girls. Bone properties were measured using DXA, pQCT, and ultrasound. Also, serum P1NP, OC, B-ALP, and TRACP 5b were assessed. Our results showed that girls with the TT genotype had significantly lower BMC and BMD of the total body, lumbar spine, and proximal femur, as well as BUA at the calcaneus, than those with the GT and GG genotype. …
Screw‐in‐screw fixation of fragility sacrum fractures provides high stability without loosening—biomechanical evaluation of a new concept
2020
Surgical treatment of fragility sacrum fractures with percutaneous sacroiliac (SI) screw fixation is associated with high failure rates. Turn-out is detected in up to 20% of the patients. The aim of this study was to evaluate a new screw-in-screw implant prototype for fragility sacrum fracture fixation. Twenty-seven artificial hemipelvises were assigned to three groups (n = 9) for instrumentation of an SI screw, the new screw-in-screw implant prototype, ora transsacral screw. Before implantation, a vertical osteotomy was set in zone 1 after Denis. All specimens were biomechanically tested to failure in upright position. Validated setup and test protocol were used for complex axial and torsi…
Improving the cementation of the tibial component in knee arthroplasty : a study of four techniques in the cadaver.
2021
Aims The main objective of this study is to analyze the penetration of bone cement in four different full cementation techniques of the tibial tray. Methods In order to determine the best tibial tray cementation technique, we applied cement to 40 cryopreserved donor tibiae by four different techniques: 1) double-layer cementation of the tibial component and tibial bone with bone restrictor; 2) metallic cementation of the tibial component without bone restrictor; 3) bone cementation of the tibia with bone restrictor; and 4) superficial bone cementation of the tibia and metallic keel cementation of the tibial component without bone restrictor. We performed CT exams of all 40 subjects, and mea…
Identifizierung unbekannter Leichen durch Röntgenbildvergleich
1995
Between 1987 and 1993, 30 unknown bodies were identified by means of pre- and postmortem radiographs at the Forensic Institute in Mainz. Our experience indicates that radiological identification comprises a useful, rapid and cheap method, at least as valuable as dactyloscopy or odontological comparisons. The ages of available radiographs were up to 25 years; the most suitable regions are the skull (11), pelvis and lumbar spine (6), lower femur and knee (5) and distal leg with the ankle joint (5). In respect of the problem of objectifying the probability of identity, possibilities for solutions are shown.
The Skull in Achondroplasia
1988
The growth disorder in achondroplasia results from abnormalities of endochondral bone formation. Cranial abnormalities originate from the occipital bone, the only region where enchondral bone is formed.
Reaction of the bone structure to methotrexate-Palacos flow y. Experimental investigations in animals.
1989
With the combined osteosynthesis of pathological fractures in association with tumors and/or metastases in mind, E. Merck (Darmstadt, FRG) developed a bone cement containing a cytostatic agent, methotrexate-Palacos flow y (MTX-Pf). The animal-experimental study presented here investigates the tolerability of MTX-Pf in the femurs of rabbits with lateral comparison. In these investigations we used both the concentration of 0.63% MTX, as is currently used in standard clinical surgery, as well as a much higher concentration of 2.5% MTX. The histological sections were investigated using microradiographic methods and provided no indication of any significant differences between the femora with th…
Does hysterectomy with ovarian conservation affect bone metabolism and density?
2002
We evaluated whether hysterectomy with ovarian conservation (HYX) has an effect on bone metabolism and density in 176 healthy Caucasian postmenopausal women aged 48-59 years. Bone properties of the hip, spine, radius, tibia, and calcaneus were measured using different bone assessment modalities. In addition, bone turnover was assessed using serum bone-specific alkaline phosphatase (BAP), osteocalcin (OC), and tartrate-resistant acid phosphatase (TRAP) 5b as biomarkers. Our results showed that women having HYX had a significantly lower level of OC ( P = 0.017) and a marginally lower level of TRAP 5b ( P = 0.051) and higher bone mineral density (BMD) of the femoral neck ( P = 0.037) and lumba…