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| 2. |
- Abul-Kasim, Kasim, et al.
(författare)
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Optimization of Radiation Exposure and Image Quality of the Cone-beam O-arm Intraoperative Imaging System in Spinal Surgery.
- 2012
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Ingår i: Journal of Spinal Disorders and Techniques. - 1539-2465. ; 25:1, s. 52-58
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Tidskriftsartikel (refereegranskat)abstract
- STUDY DESIGN: Retrospective study. OBJECTIVES: To optimize the radiation doses and image quality for the cone-beam O-arm surgical imaging system in spinal surgery. SUMMARY OF BACKGROUND: Neurovascular compromise has been reported after screw misplacement during thoracic pedicle screw insertion. The use of O-arm with or without navigation system during spinal surgery has been shown to lower the rate of screw misplacement. The main drawback of such imaging surgical systems is the high radiation exposure. METHODS: Chest phantom and cadaveric pig spine were examined on the O-arm with different scan settings: 2 were recommended by the O-arm manufacturer (120 kV/320 mAs, and 120 kV/128 mAs), and 3 low-dose settings (80 kV/80 mAs, 80 kV/40 mAs, and 60 kV/40 mAs). The radiation doses were estimated by Monte Carlo calculations. Objective evaluation of image quality included interobserver agreement in the measurement of pedicular width in chest phantom and assessment of screw placement in cadaveric pig spine. RESULTS: The effective dose/cm for 120 kV/320 mAs scan was 13, 26, and 69 times higher than those delivered with 80 kV/80 mAs, 80 kV/40 mAs, and 60 kV/40 mAs scans, respectively. Images with 60 kV/40 mAs were unreliable. Images with 80 kV/80 mAs were considered reliable with good interobserver agreement when measuring the pedicular width (random error 0.38 mm and intraclass correlation coefficient 0.979) and almost perfect agreement when evaluating the screw placement (κ value 0.86). CONCLUSIONS: The radiation doses of the O-arm system can be reduced 5 to 13 times without negative impact on image quality with regard to information required for spinal surgery.
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| 3. |
- Karlsson, Magnus K, et al.
(författare)
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Characteristics of Prevalent Vertebral Fractures Predict New Fractures in Elderly Men.
- 2016
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Ingår i: Journal of Bone and Joint Surgery. American Volume. - 1535-1386. ; 98:5, s. 379-385
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Tidskriftsartikel (refereegranskat)abstract
- Studies have shown that specific characteristics of prevalent vertebral fractures are associated with a markedly low bone mineral density. This study evaluates if these characteristics also predict subsequent fractures.
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| 6. |
- Kherad, Mehrsa, et al.
(författare)
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Risk factors for low back pain and sciatica in elderly men-the MrOS Sweden study
- 2017
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Ingår i: Age and Ageing. - : Oxford University Press (OUP). - 0002-0729 .- 1468-2834. ; 46:1, s. 64-71
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: the aim of this study was to identify whether factors beyond anatomical abnormalities are associated with low back pain (LBP) and LBP with sciatica (SCI) in older men. MATERIAL AND METHODS: Mister Osteoporosis Sweden includes 3,014 men aged 69-81 years. They answered questionnaires on lifestyle and whether they had experienced LBP and SCI during the preceding 12 months. About 3,007 men answered the back pain (BP) questions, 258 reported BP without specified region. We identified 1,388 with no BP, 1,361 with any LBP (regardless of SCI), 1,074 of those with LBP also indicated if they had experienced LBP (n = 615), LBP+SCI (n = 459). RESULTS: about 49% of those with LBP and 54% of those with LBP+SCI rated their health as poor/very poor (P < 0.001). Men with any LBP to a greater extent than those without BP had poor self-estimated health, depressive symptoms, dizziness, fall tendency, serious comorbidity (diabetes, stroke, coronary heart disease, pulmonary disease and/or cancer) (all P < 0.001), foreign background, were smokers (all P < 0.01), had low physical activity and used walking aids (all P < 0.05). Men with LBP+SCI to a greater extent than those with LBP had lower education, lower self-estimated health, comorbidity, dizziness and used walking aids (all P < 0.001). CONCLUSIONS: in older men with LBP and SCI, anatomical abnormalities such as vertebral fractures, metastases, central or lateral spinal stenosis or degenerative conditions may only in part explain prevalent symptoms and disability. Social and lifestyle factors must also be evaluated since they are associated not only with unspecific LBP but also with LBP with SCI.
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| 7. |
- Kherad, Mehrsa
(författare)
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The clinical relevance of vertebral fractures and low back pain in elderly men
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The number of vertebral fractures has increased during the last few decades.The increase could at least partly be explained by the increasing proportion of elderly in society since these fractures are more commonly found in elderly than in young individuals. Low bone mass and osteoporosis which are also partly related to aging are risk factors for fracture but both age and low bone mass are independent risk factors for fracture. Furthermore, a vertebral fracture is itself a risk factor for future fractures. Our knowledge regarding prevalent vertebral fractures and their association with future fractures and back pain is predominantly derived from studies in women. Whether the same applies to men is less evaluated. This thesis therefore focuses on elderly men. In this thesis we cross-sectionally evaluated the epidemiology of prevalent vertebral fractures in elderly Swedish men and their association with back pain, low bone mass density and osteoporosis and prospectively evaluated if specific characteristics of prevalent vertebral fractures predict future fractures. In a cross-sectional study design we also identified factors associated with low back pain (LBP) and sciatica (SCI). Our aim was to evaluate (i) whether a prevalent vertebral fracture is associated with back pain in elderly men (ii) if a prevalent vertebral fracture and specific characteristics of a prevalent vertebral fracture is associated with back pain, low bone mineral density, osteoporosis and future fractures and (iii) whether lifestyle and social factors are more associated with not only low back pain but also sciatica in elderly men. We used the Osteoporotic Fractures in Men Sweden (MrOs) Study, a population-based cohort of 3014 community dwelling men aged 69—81 years recruited in the cities of Malmö (n=1005), Gothenburg (n=1010) and Uppsala (n=999). The primary aim of the study is to evaluate prospectively the risk factors for osteoporosis and fractures. At baseline these men answered a questionnaire that evaluated fracture history and life style along with the occurrence of back pain, low back pain and sciatica during the preceding 12 months. They also had their total body, total hip and lumbar spine BMD measured by dual energy X-ray absorptiometry (DXA). Also 988 of the men in Malmö and 465 of the men in Gothenburg underwent a lateral thoracic and lumbar spine radiograph. Clinical and radiographically verified fractures that occurred after baseline were registered for a mean 10 years by repeated review of the archives of the respective radiographic departments. This thesis shows that a prevalent vertebral fracture in elderly men is of low clinical relevance in respect of back pain, that lifestyle and social factors are associated with not only LBP but also LBP and SCI and that a prevalent vertebral fracture and especially those fractures with specific characteristics, could be used to identify individuals at high risk of having osteoporosis and sustaining new fractures.
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| 8. |
- Kherad, Mehrsa, et al.
(författare)
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The number and characteristics of prevalent vertebral fractures in elderly men are associated with low bone mass and osteoporosis.
- 2015
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Ingår i: The bone & joint journal. - 2049-4408. ; 97-B:8, s. 1106-10
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Tidskriftsartikel (refereegranskat)abstract
- We sought to determine whether specific characteristics of vertebral fractures in elderly men are associated with low bone mineral density (BMD) and osteoporosis. Mister Osteoporosis Sweden is a population based cohort study involving 3014 men aged 69 to 81 years. Of these, 1427 had readable lateral radiographs of the thoracic and lumbar spine. Total body (TB) BMD (g/cm²) and total right hip (TH) BMD were measured by dual energy x-ray absorptiometry. The proportion of men with osteoporosis was calculated from TH BMD. There were 215 men (15.1%) with a vertebral fracture. Those with a fracture had lower TB BMD than those without (p < 0.001). Among men with a fracture, TB BMD was lower in those with more than three fractures (p = 0.02), those with biconcave fractures (p = 0.02) and those with vertebral body compression of > 42% (worst quartile) (p = 0.03). The mean odds ratio (OR) for having osteoporosis when having any type of vertebral fracture was 6.1 (95% confidence interval (CI) 3.9 to 9.5) compared with those without a fracture. A combination of more than three fractures and compression in the worst quartile had a mean OR of 114.2 (95% CI 6.7 to 1938.3) of having osteoporosis compared with those without a fracture. We recommend BMD studies to be undertaken in these subcohorts of elderly men with a vertebral fracture.
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| 9. |
- Tiderius, Carl Johan, et al.
(författare)
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Hur många kroppsdelar ska få offras?
- 2012
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Ingår i: Läkartidningen. - 0023-7205. ; 109:51-52, s. 2332-2333
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Tidskriftsartikel (refereegranskat)
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