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Czy opatrunek gipsowy wpływa na indeks ekspozycji i dose area product? : Odpowiedź na przykładzie radiografii nadgarstka

Nowak P., Murzyn K., Pasieka E.

Inżynier i Fizyk Medyczny

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2018

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Vol. 7, nr 2

85--91

PL

Złamania dystalnej części kości promieniowej należą do jednych z najczęstszych urazów kości. W przypadku tego typu urazów podstawnym badaniem obrazowym, ze względu na niski koszt wykonania i ogólną dostępność, jest zdjęcie rentgenowskie. Standardowo radiografię stawu nadgarstkowego wykonuje się w projekcji: tylno-przedniej, skośnej i bocznej. Dodatkowymi badaniami są radiogramy w odchyleniu promieniowym lub łokciowym, a także zdjęcie celowane na kanał nadgarstka oraz kość łódeczkowatą. Cel: Celem pracy była retrospektywna analiza wartości dose area product i indeksu ekspozycji podczas radiografii stawu nadgarstkowego u pacjentów z zastosowanym opatrunkiem gipsowym oraz bez, w zależności od wielkości pola kolimacji rentgenogramu, a także wykorzystanych do diagnostyki parametrów ekspozycji. Materiały i metody: Analizie retrospektywnej poddano 208 losowo wybranych radiogramów stawu nadgarstkowego wykonanych w Zakładzie Radiologii Uniwersyteckiego Szpitala Klinicznego w Białymstoku aparatem RTG Axiom Aristos firmy Siemens. Badanie obejmowało wartości dose area product i indeksu ekspozycji, napięcia anodowego, obciążenia prądowo-czasowego oraz wiel¬kości pól kolimacji. Zebrane dane poddano analizie statystycznej przy użyciu programu Statistica 12,5 oraz MS Excel 2013. Wyniki: Większą część osób, którym wykonano radiogramy, sta¬nowiły kobiety. W tej grupie średnia wieku wyniosła 63,79 lat, natomiast średnia wieku mężczyzn była równa 47,56 lat. Średnia wielkość pola kolimacji rentgenogramu z grupy objętej bada¬niem wyniosła 324,17 cm2. Przy założeniu, że wartość referen¬cyjna pola kolimacji wynosi 234 cm2 (13 x 18 cm), to 160 (72,92%) zdjęć miało pole kolimacji większe od wartości referencyjnej, natomiast przy przyjęciu 432 cm2 (18 x 24 cm) jako wartość odniesienia tylko 35 (16,83%) radiogramów było większych od wartości wzorcowej. Wartość współczynnika ekspozycji wynio¬sła średnio 645,87 z wartością maksymalną równą 2980,00, na¬tomiast najniższa wartość była równa 141,00. Średnia wartość DAP w grupie objętej badaniem wyniosła 0,02 Gy∙cm2, przy od¬chyleniu standardowym 0,01 Gy∙cm2. Największa odnotowana wartość współczynnika DAP wyniosła 0,07 Gy∙cm2, natomiast najmniejsza 0,01 Gy∙cm2. Testy statystyczne wykazały korelację między polem powierzchni a DAP na poziomie rs = 0,78 i polem powierzchni a EXI rs = 0,19 oraz między wartością DAP (p = 0,00) i EXI (p = 0,00) a obecnością opatrunku gipsowego. Wnioski: W radiografii cyfrowej bezpośredniej (system Siemens) opatrunek gipsowy wpływa w istotny sposób na wartości DAP, zwiększając go średnio o 0,01 Gy∙cm2 oraz EXI, zmniejszając jego wartość niemal o połowę. Także zwiększenie pola kolimacji po¬woduje zwiększenie wartości DAP i EXI w radiografii nadgarstka.

EN

Distal part radial bone fractures are one of the most common types of trauma. The basis of imaging examination of the injury is radiography. The advantages of the X-ray examination are low costs and widespread availability. Standard projections for the wrist are posteroanterior and lateral views. However, there are many ancillary views like a radiograms obtained with radial or ulnar deviation and carpal tunel. Aim: The aim of the study is retrospective analysis of dose area product and exposure index during radiography of the wrist. The analysis included value collimation size and exposure para¬meters depending on whether plaster immobilization was used or not. Materials and methods: We conduct retrospective analysis of randomly selected 208 radiographs of the wrist. X-ray photos were taken of patients at the Department of Radiology, Medi¬cal University Hospital in Bialystok, with Axiom Aristos Siemens. The analysis included value of the dose area product, exposure index, tube potential, tube current-time product and collima¬tion field. Statistical analysis was done using Statistica 12.5 and MS Excel 2013. Results: The most frequently radiographs were taken for wo¬men which average age was 63,79 while average age for men was 47,56. The average size of X-ray was 324,17 cm2. Assuming that the reference value of the collimation field is 234 cm2 (160x160), 160 (72.92%) images had collimation field greater than reference value. On the other hand when reference va¬lue is 432 cm2 (18 x 24 cm) only 35 (16.83%) of the radiographs were greater. The average exposure index value was 645,87, while the maximum value was 2980,00 and minimum value was 141,00. The average DAP in study group was 0,02 Gy∙cm2, SD = 0,01 Gy∙cm2. The largest recorded DAP was 0,07 Gy∙cm2, while the smallest was 0,01 Gy∙cm2. Statistic tests showed a signifi¬cant dependence between collimation field size value and DAP (rs = 0 ,78), c ollimation fi eld s ize v alue a nd E XI ( rs = 0 ,19); D AP (p = 0,00) and EXI (p = 0,00), and presence of plaster cast. Conclusions: In digital radiology (Siemens), plaster cast have a si¬gnificant influence on DAP, increasing it 0,01 Gy∙cm2 on average and EXI reduced its value almost by half. The increased surface area of the radiographs causes increased DAP and EXI.

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Comparative analysis for kinematics of 5-DOF industrial robotic manipulator

Manjaree S., Nakra B. C., Agarwal V.

Acta Mechanica et Automatica

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2015

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Vol. 9, no. 4

229--240

EN

This paper gives the kinematic analysis of a 5-DOF industrial robotic manipulator while considering wrist in motion. Analytical solutions have been obtained for forward kinematics and inverse kinematics to accurately position the end-effector of robotic manipulator in three dimensional spaces. For the first time, a hybrid neuro-fuzzy intelligent technique with two different membership functions has been studied and their performances are comparatively evaluated with analytical solutions. An experiment has been performed for a desired trajectory. It is seen that the results for the intelligent technique are reasonably in agreement with experiment. Also, the results obtained highlight the importance of selection of a particular membership function for robotic manipulators of industrial use.

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Flexion and Extension Angles of Resting Fingers and Wrist

Lee K.-S., Jung M.- C.

International Journal of Occupational Safety and Ergonomics

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2014

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Vol. 20, No. 1

91--101

EN

This study determined flexion and extension angles of resting fingers and wrist in terms of forearm posture (neutral, pronation and supination) and shoulder flexion (0°, 45°, 90° and 135°). The participants participated in 12 angle measurements for 16 finger joints and wrist. The finger joints flexed more in supination than in neutral posture and pronation and the thumb flexed more than the other fingers because of the gravity and skin tension. This phenomenon became more apparent as the shoulder flexed. The carpometacarpal joint had the largest flexion angle in the thumb joints, whereas the proximal interphalangeal joints had the largest flexion angles in the other finger joints. The resting posture of the wrist extended of ~16° in any forearm postures when the shoulder was at 0°. The results of this study could be useful for rehabilitation tool and product designs.

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Prototyp urządzenia do ćwiczeń czynnych w odciążeniu z oporem mięśni prostowników palców i nadgarstka

Musiolik A., Jureczko P.

Aktualne Problemy Biomechaniki

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2008

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z. 2

115--122

PL

W artykule zostały przedstawione dostępne na rynku urządzenia do rehabilitacji ręki. Dodatkowo przeprowadzono badanie w systemie BTS SMART w celu wyznaczenia prędkości i przyspieszeń ręki. Ponadto zaproponowano nowy model prototypu urządzenia do rehabilitacji ręki dla chorych z niedowładem połowicznym kończyny górnej lewej i prawej po urazach mózgowych.

EN

This paper is a demonstration of the prototype of the device to active practices in the relief with the resistance of the muscles rectifiers to the fingers, with the partial paresis of the upper limb left and / or right after cerebral injuries. Furthermore it includes a investigation of the hand in the BTS SMART Software and results.

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Computer Professionals and Carpal Tunnel Syndrome (CTS)

Ali K. M., Sathiyasekaran B. W. C.

International Journal of Occupational Safety and Ergonomics

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2006

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Vol. 12, No. 3

319--325

EN

Carpal Tunnel Syndrome (CTS) is an important problem among computer professionals. Hence the prevalence of CTS among computer professionals and risk factors were studied. 648 subjects were selected from 4,276 computer professionals from 21 companies with a simple random sampling method. CTS was diagnosed based on clinical features.The prevalence of CTS was found to be 13.1% (95% CI 10.5–15.7%). Subjects with over 8 years of computer work, over 12 hrs of work per day and system administrators were at a higher risk for CTS (OR 3.3, 4.9 and 2.5 respectively). Flexed or extended hand position had higher risk for CTS. Higher risk for CTS was found with higher exposure to computer work. Ergonomic considerations are important in facilitating proper positioning of hand while working with a computer. Further studies on CTS risk factors among computer professionals are essential for planning prevention.

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Relevance of the EMG/Grip Relationship in Isometric Anisotonic Conditions

Claudon L.

International Journal of Occupational Safety and Ergonomics

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2003

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Vol. 9, No. 2

121--134

EN

The aim of the present study was to develop a relationship to evaluate grip force using the electromyogram (EMG) in isometric anisotonic conditions. The EMGs of the flexor digitorum superficialis (FDS) and the extensor digitorum (ED) were recorded in 3 flexion-extension positions of the wrist (30° flexion, 30° extension, and 60° extension) associated with 3 positions of the forearm (70° pronation, prono-supination, and 70° supination). For each position, the participants had to follow linear ramp targets (2 rates of increase and decrease) displayed on an oscilloscope. The results show the best fit is a quadratic type force-EMG relationship. Some aspects such as the rate of force variation and the forearm and wrist positions are then discussed along with the limitations of the relationship.

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Effects of Ergorest Arm Supports on Muscle Strain and Wrist Positions During the Use of the Mouse and Keyboard in Work With Visual Display Units: A Work Site Intervention

Lintula M., Nevala-Puranen N., Louhevaara V.

International Journal of Occupational Safety and Ergonomics

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2001

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Vol. 7, No. 1

103--116

EN

The effects of Ergorest arm supports on wrist angles and musculoskeletal strain in the neck-shoulder-arm region and electrical activity in the shoulder and arm muscles were studied during typing or the use of the mouse in work with a visual display unit (VDU). Twenty-one women were randomized into 3 groups (1 arm support, 2 arm supports, and control). Measurements were carried out before and after the 6-week intervention. The wrist extension of the mouse hand, the muscle activity of the trapezius muscle, and the subjective discomfort ratings indicated that 2 arm supports were better than 1 in work with a mouse. The Ergorest arm support alleviates muscle and joint strain in VDU work when used for both arms.

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Evaluation of Grip Force Using Electromyograms in Isometric Isotonic Conditions

Claudon L.

International Journal of Occupational Safety and Ergonomics

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1998

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Vol. 4, No. 2

169--184

EN

The purpose of this study was to develop a relationship to evaluate the grip force (forcerel) using the electromyogram (EMGrel) of the flexor digitorum superficialis (FDS) and of the extensor digitorum (ED) according to the flexion-extension wrist angle (0t-e) and to the pronation-supination forearm angle (0p-s). Fifteen participants had to exert 3 levels of grip forces in 4 positions of the wrist combined with 3 positions of the forearm. The relationship is: forcerel = 0.0045 • 0t-e • EMGrel(FDS) + 0.48 • EMGrel(FDS)-0.0014 • 0t-e • EMGrel(ED) -0 .0016 • 0p-s • EMGrel(ED) • 0.4- EMGrel(ED) This relationship can be used to estimate grip force for levels of strength lower than 50% of the maximal voluntary contraction.