Search results for "BONE"
showing 10 items of 2629 documents
Die Kleinfragment-Doppelplattenosteosynthese bei C1- bis C3-Frakturen des Pilon tibiale
2008
Intra-articular fractures of the tibial pilon always have been a challenge for the surgeon and his operative technique. With conservative or operative management, we have to take care of destroyed articular surfaces and traumatised soft tissues. Therefore, tibial pilon fractures are known in the literature as complicated lesions with a high rate of complications. Between 1993 and 2001 twenty-one patients who were between 18 and 65 years old and suffered a monotrauma of the tibial pilon of the type C1 to C3 of the AO classification, were treated with a staged reconstruction. Stabilisation was done by small-fragment double plate osteosynthesis. In this retrospective study, we could review 17 …
Management of Osteoporosis in Postmenopausal Women
2019
Osteoporosis is a noncommunicable disease with increasing incidence at a global level. The burden of the disease particularly concerns women. A drastic and rapid decline in the circulating levels of estrogens, a key regulator of bone metabolism, is responsible for the increase in bone loss after menopause. Cells with a role in bone metabolism, osteoblasts, osteoclasts and osteocytes, have estrogen receptors. The fall in estrogens increases the differentiation of osteoclasts from progenitors in the bone marrow. A significant expansion in the resorption process follows.
Distal Humerus Fractures
2014
Distal humerus fractures display seldom but severe injuries because of the complex distal humerus anatomy and often comminuted fracture types. They account for approximately 2–3 % of all fractures and for 17–30 % of fractures around the elbow. In younger patients, there is a predominance among males. The mechanism of accident is mostly a high-energy trauma in this population. In contrast, among elderly patients, distal humerus fractures concern mostly women with osteoporotic bone. Fractures are caused by a low-energy trauma such as a fall from standing height onto the outstretched or slightly flexed arm. These fractures are often severely comminuted. Because of the thin soft tissue envelope…
Bestimmung der Knochenqualität vor Wirbelsäuleninstrumentation - Stellenwert verschiedener in vivo-Methoden
2008
OBJECTIVE: The present investigation should elucidate which assessment technique for bone quality is most appropriate to estimate preoperatively fixation strength of instrumental spine fusions. METHODS: VDS-screw fixation strength in 50 human cadaveric vertebral bodies was approximated by means of pullout force assessment. Bone quality was assessed by Dual Energy X-ray Absorptiometry (DEXA), Quantitative Computed Tomography (QCT), MRT and histomorphometry. For each of these techniques, correlation with axial pull out force strength was investigated. RESULTS: Highest correlation was found for cancellous bone density (QCT) (r = 0.72; p < 0.001) and DEXA (r = 0.70; p < 0.001). MRT, cortical bo…
Operator-Related Errors and Pitfalls in Dual Energy X-Ray Absorptiometry: How to Recognize and Avoid Them.
2020
Dual-energy X-ray absorptiometry (DXA) is the most common modality for quantitative measurements of bone mineral density. Nevertheless, errors related to this exam are still very common, and may significantly impact on the final diagnosis and therapy. Operator-related errors may occur during each DXA step and can be related to wrong patient positioning, error in the acquisition process or in the scan analysis. The aim of this review is to provide a practical guide on how to recognize such errors in spine and hip DXA scan and how to avoid them, also presenting some of the most common artifacts encountered in clinical practice.
The effect of cement fixation on initial micromotion of the femoral component in condylar knee replacement
1992
Four fresh, cadaveric specimens were fitted with total knee replacements and mounted on a knee joint loading and measuring rig. Femoral component micromotion in the sagittal plane was measured with a transducer during flexion and extension of the specimen. Various condylar designs were used without and with cement. Movement followed a characteristic curve pattern and was less with cement fixation particularly for bone of low trabecular strength as determined by bone sample tests for stiffness. Cement fixation appears to be superior to cementless fixation.
Growth and aging of proximal femoral bone - a study with women spanning three generations
2015
Abstract. Osteoporotic hip fracture is a serious clinical event associated with high morbidity and mortality. Understanding femoral growth patterns is important for promoting bone health in the young and preventing fractures in later life. In this study, growth patterns of areal bone mineral density (aBMD) and geometric properties of the proximal femur were measured by dual-energy X-ray absorptiometry (GE Lunar Prodigy, USA). They were studied in 251 girls from premenarche (11.2±0.7 yrs) to late adolescence (18.3±1.1 yrs), and compared to their premenopausal mothers (n=128, aged 44.9±4.1 yrs) and postmenopausal grandmothers (n=128, aged 70.0±6.3 yrs). Hip axis length (HAL) was the first to …
Exercise for bone and cartilage in postmenopausal women with mild knee osteoarthritis
2016
The purpose of this study was to investigate the effects of high-impact exercise on bone mineral mass and strength, and on knee cartilage composition in postmenopausal women with mild knee osteoarthritis (OA). In addition, the association between knee OA and femoral neck bone structural characteristics in women with mild knee radiographic OA and those without radiographic knee OA was studied. Also, the reproducibility of measuring human knee joint cartilage by the delayed gadolinium-enhanced MRI (dGEMRIC) technique was determined in healthy asymptomatic subjects. Data from a 12-month randomized controlled trial (RCT) was used to assess the effects of exercise on bones and cartilages. The tr…
Bone mineral density of the proximal femur after hip resurfacing arthroplasty: 1-year follow-up study
2011
Abstract Background Hip resurfacing arthroplasty (HRA) is considered a bone-preserving procedure and may eliminate proximal femoral stress shielding and osteolysis. However, in addition to implant-related stress-shielding factors, various patient-related factors may also have an effect on bone mineral density (BMD) of the proximal femur in patients with HRA. Thus, we studied the effects of stem-neck angle, demographic variables, and physical functioning on the BMD of the proximal femur in a one-year follow-up. Methods Thirty three patients (9 females and 24 males) with a mean (SD) age of 55 (9) years were included in the study. BMD was measured two days and 3, 6, and 12 months postoperative…
In Vitro Study on Bone Heating during Drilling of the Implant Site: Material, Design and Wear of the Surgical Drill
2020
Objective: An in vitro study was made to compare mean thermal variation according to the material, design and wear of the surgical drills used during dental implant site preparation. Material and methods: Three study groups (stainless steel drills with straight blades