Since the advent of keyboards into the workplace, workers began to experience disorders of the tendons and nerves of the upper extremities, referred to as cumulative trauma disorders, due to the repeated exertions and excessive movements. One of the major research voids in the study of occupational injuries to the wrist is the lack of understanding of the kinematic nature of the wrist during keying tasks. Changes in wrist position were measured on 9 males and 9 females while keying, in the flexion/extension and radial/ ulnar planes. This information was then used to determine the wrist dynamic characteristics, then wrist accelerations were derived. The effects of Gender, Keyboard Height (5 cm below sitting elbow height, at sitting elbow height, 5 cm above elbow height), Keyboard Angle (-30 degrees from horizontal, horizontal, +30 from horizontal), and Keying Rate( 110 and 90 percent of the individual's average typing rate) on wrist accelerations were scrutinized. The results of this study indicated that, throughout the keying task, there were a significant changes in wrist position (p < 0.05). Keyboard Height was the only significant variable (p < 0.05) on the magnitude of mean peak wrist acceleration. The lowest magnitude of wrist acceleration occurred when the keyboard was positioned 5 cm below the user's sitting elbow height From these findings it appears that the methods used were effective in determining the kinematic nature of the wrist during a keying task. Specifically, the technique employed is adequate for measuring the accelerations of the wrist, but future research is needed to more accurately define the factors that influence the magnitude of wrist accelerations. / Master of Science

Two-thirds of repetitive strain injuries affect the wrist joint. Although force is believed to be one of the major factors, the forces involved in wrist movements have not been thoroughly characterized in vivo. Computer simulations with a musculoskeletal model of the wrist have been used to estimate wrist muscle forces, but only at maximum voluntary contraction and only involving a single degree of freedom (DOF). In this study we present a method for creating a subject-specific model that can be used to estimate muscle forces and joint torques in both degrees of freedom of the wrist over a range of torques applicable to activities of daily living. Ten young, healthy subjects applied three levels of isometric wrist torque (about 7, 15, and 25% of maximum torque) in combinations of wrist flexion-extension and radial-ulnar deviation while joint torque in both DOF and surface electromyograms (sEMG) in the five major wrist muscles were measured. To find subject-specific parameters, we followed a two-step process. First, a pre-existing, generic musculoskeletal model of the wrist was scaled to individual subjects' height. Second, we compared joint torques predicted from measured sEMG using forward simulations of muscular dynamics to measured torques and minimized this error to optimize for subject-specific model parameter values. The model parameters optimized were the maximum isometric force and tendon slack length of each muscle. Optimization constraints were added to ensure physiologically plausible combinations of parameter values. The optimization produced model parameters that 1) were in a reasonable physiological range for each test subject and 2) significantly improved the accuracy of the model’s torque estimation. Scaling the generic model reduced the root mean squared (RMS) error between predicted and measured joint torques by 2.8±4.6% (mean±SD), whereas optimizing the scaled model further reduced the RMS error by 51.4±18.9% for the torque level at which the model was optimized. Testing the optimized model at other torque levels still significantly reduced the error between predicted and measured torques compared to the scaled model (43.7±28.0% and 25.0±24.0% for lower and higher torque levels, respectively). The mean error between predicted and measured torque was 0.23±0.04, 0.30±0.04, and 1.17±0.26 Nm at the low-, mid-, and high-torque levels, respectively. The method generally reduced the error in flexion-extension (FE) more than radial-ulnar deviation (RUD), likely in part because sEMG and torque were larger in FE than in RUD. Optimizing for subject-specific model parameters significantly improved prediction over both the generic and scaled models, in both degrees of freedom of the wrist, and at all three torque levels. The presented method for creating subject-specific models can be used in future studies to quantify muscle forces and joint torques of natural wrist movements in vivo.

No description available.

No description available.

The elderly population is increasing at a rapid rate each year, and with the increase in the elderly population there is a need for better medical assistance and devices. The greatest problem this demographic is facing is the ability to age in place. More elderly people are being placed in nursing homes, assisted living homes, moving in with relatives due to disabilities or fear of disabilities caused by a life threaten event such as heart disease, stroke, falling/fainting, or uncontrolled glucose levels. Falling is the number one leading cause of deaths, injuries and incapacity in the elderly. Stroke is the 3rd leading cause of death in the U.S; it is the 2nd leading cause worldwide. Rapid change in glucose levels is another leading cause of disabilities and deaths. Heart disease is the 2nd leading cause of death in the elderly. These life threatening events can be prevented and if treated early enough can allow the person to have a full recovery and continue to age in place. A device was proposed that could monitor these four life threatening events: heart disease, stroke, falling/fainting and changes in glucose levels. This device will monitor the user continuously. Research was conducted to see what other products are on the market and how they detect these events and how reliable they are for the user. A literature review was performed to understand what other people are doing to solve the aging in place problem. Using this and needs assessment of the elderly, the system architecture for the wrist worn device was designed along with a testing plan and procedure. More research needs to be done in certain areas to better improve solutions and technology in the area aging in place of the elderly. Before this device can bridge some of the gaps between the current issues and the solution the device will have to be tested for several things such as its ability to differentiate between stimulated falling/fainting and fall like activities such as sitting then lying. The orientation and position will be tested to see if the device can actually tell where the person is located. The device will have to be tested against well-known devices and see if it gives similar precise and accurate readings in real time. / Master of Science

Of the studies that considered negatively sloped keyboards, results showed improved comfort and postural effects while typing on keyboards; however, few studies of negatively sloped keyboard angles and their resulting effects on objective physiological measures, psychological measures, and performance have been performed. The objective of this study was to quantify the effects of negative keyboard slopes on forearm muscle activity, wrist posture, key strike force, perceived discomfort, and performance to identify a negative keyboard angle or range of keyboard angles that minimizes exposure to hypothesized risk factors for hand/wrist work related musculoskeletal disorders. Ten experienced typists (4 males and 6 females) participated in a laboratory study to compare keyboard slopes ranging from 7° to -30°, at 10° increments from 0° to -30°, using an experimental wedge designed for use with QWERTY keyboards. Repeatability was examined by requiring participants to complete the experiment in two test sessions one week apart. Dependent variable data was collected during 10 minute test sessions. Wrist posture data revealed postural benefits for negative angles of 0° or greater compared to 7°. Specifically, the percentage of wrist movements within a neutral zone and percentage of wrist movements within ±5° and ±10° degrees increased as keyboard angle became more negative. EMG results were mixed with some variables supporting negative keyboard angles, while other results favored the standard keyboard configuration. Net typing speed supported the -10° keyboard angle, while other negative typing angles were comparable, if not better, than the standard. These findings showed that there was strong support for improved postural changes associated with negatively sloped keyboard wedges, though user perceptions favored the standard configuration. / Master of Science

Introdução: Ao analisar a osteoartrose pós-traumática do punho a literatura demonstra que sua etiologia é, na maioria das vezes, secundária a lesões ligamentares ou a fraturas do carpo que, por sua vez, seguem um padrão definido e evolutivo de acometimento articular do punho. Várias abordagens cirúrgicas são descritas para o tratamento da osteoartrose pós-traumática do carpo. Considerando a carpectomia proximal e a artrodese dos quatro cantos, a literatura apresenta apenas estudos retrospectivos comparando os resultados funcionais entre as técnicas. O objetivo desta tese é comparar os resultados funcionais entre a carpectomia proximal e a artrodese dos quatro cantos no tratamento da osteoartrose pós-traumática do punho, sem acometimento da articulação mediocárpica. Método: Neste estudo prospectivo e randomizado 20 pacientes portadores de osteoartrose pós-traumática sem acometimento da articulação mediocárpica do punho, submetidos à carpectomia proximal ou a artrodese dos quatro cantos tiveram seus dados pós-operatórios analisados e comparados. Resultados: Todos os pacientes deste estudo referiram melhora da dor e da sua capacidade funcional. Em todos os casos houve diminuição dos valores pré e pós-operatórios de goniometria em ambos os procedimentos. Não houve diferença estatisticamente significante entre os procedimentos. Conclusão: Com relação aos resultados funcionais, a carpectomia proximal e a artrodese dos quatro cantos são procedimentos efetivos e semelhantes no tratamento dos pacientes portadores de SLAC/SNAC WRIST sem acometimento da articulação mediocárpica. / Introduction: Wrist arthritis results most of the times from ligaments tears or carpal bones fractures. Many surgical procedures are described in literature. Regarding proximal row carpectomy and four corner arthrodesis, there are only retrospective studies available in literature. The objective of this study is to compare the functional results between these two surgical procedures. Method: In this prospective and randomized study 20 patients underwent proximal row carpectomy or four corner arthrodesis for the treatment of wrist arthritis. In all patients the midcarpal joints were free of lesions. Functional results were compared. Results: Both proximal row carpectomy and four corner arthrodesis improved pain. All cases showed decreased range of motion after surgery. The differences between the groups were not statistically significant. Conclusion: Regarding functional results both procedures were similar and improved pain in patients with SLAC/SNAC WRIST without degenerative changes in midcarpal joint.

Introdução: Ao analisar a osteoartrose pós-traumática do punho a literatura demonstra que sua etiologia é, na maioria das vezes, secundária a lesões ligamentares ou a fraturas do carpo que, por sua vez, seguem um padrão definido e evolutivo de acometimento articular do punho. Várias abordagens cirúrgicas são descritas para o tratamento da osteoartrose pós-traumática do carpo. Considerando a carpectomia proximal e a artrodese dos quatro cantos, a literatura apresenta apenas estudos retrospectivos comparando os resultados funcionais entre as técnicas. O objetivo desta tese é comparar os resultados funcionais entre a carpectomia proximal e a artrodese dos quatro cantos no tratamento da osteoartrose pós-traumática do punho, sem acometimento da articulação mediocárpica. Método: Neste estudo prospectivo e randomizado 20 pacientes portadores de osteoartrose pós-traumática sem acometimento da articulação mediocárpica do punho, submetidos à carpectomia proximal ou a artrodese dos quatro cantos tiveram seus dados pós-operatórios analisados e comparados. Resultados: Todos os pacientes deste estudo referiram melhora da dor e da sua capacidade funcional. Em todos os casos houve diminuição dos valores pré e pós-operatórios de goniometria em ambos os procedimentos. Não houve diferença estatisticamente significante entre os procedimentos. Conclusão: Com relação aos resultados funcionais, a carpectomia proximal e a artrodese dos quatro cantos são procedimentos efetivos e semelhantes no tratamento dos pacientes portadores de SLAC/SNAC WRIST sem acometimento da articulação mediocárpica. / Introduction: Wrist arthritis results most of the times from ligaments tears or carpal bones fractures. Many surgical procedures are described in literature. Regarding proximal row carpectomy and four corner arthrodesis, there are only retrospective studies available in literature. The objective of this study is to compare the functional results between these two surgical procedures. Method: In this prospective and randomized study 20 patients underwent proximal row carpectomy or four corner arthrodesis for the treatment of wrist arthritis. In all patients the midcarpal joints were free of lesions. Functional results were compared. Results: Both proximal row carpectomy and four corner arthrodesis improved pain. All cases showed decreased range of motion after surgery. The differences between the groups were not statistically significant. Conclusion: Regarding functional results both procedures were similar and improved pain in patients with SLAC/SNAC WRIST without degenerative changes in midcarpal joint.

Παρά τον μεγάλο όγκο της βιβλιογραφίας σχετικά με τα αποτελέσματα της αντιμετώπισης των ασταθών καταγμάτων του περιφερικού άκρου της κερκίδας με κλειστή ανάταξη και ελάχιστα επεμβατική οστεοσύνθεση υπάρχουν ακόμα σημαντικά αναπάντητα ερωτήματα. Πιό συγκεκριμένα, δεν υπάρχουν επαρκή στοιχεία γιά τον ρυθμό αποκατάστασης των κλινικών παραμέτρων κατά τη διάρκεια της μετατραυματικής περιόδου, γιά το τελικό αποτέλεσμα όπως εκφράζεται από τους ασθενείς με τη χρήση κλιμάκων αυτο-αξιολόγησης, καθώς και γιά τον βαθμό επίδρασης συγκεκριμένων ακτινολογικών παραμέτρων στο τελικό λειτουργικό αποτέλεσμα. Επίσης, δεν έχει διερευνηθεί ο συσχετισμός μεταξύ της ακτινολογικής παραμέτρου της παλαμιαίας γωνίας του περιφερικού άκρου της κερκίδας και των φορτίων που αναπτύσσονται στην φυσιολογική κερκιδοκαρπική άρθρωση. Η εργασία αυτή αποτελεί μία προοπτική μελέτη ασταθών καταγμάτων του περιφερικού άκρου της κερκίδας που αντιμετωπίστηκαν με κλειστή ανάταξη και ελάχιστα επεμβατική (διαδερμική) οστεοσύνθεση. Έγινε ανάλυση ακτινολογικών και κλινικών παραμέτρων καθώς και χρησιμοποίηση κλίμακας αυτο-αξιολόγησης της δυσλειτουργίας της πηχεοκαρπικής άρθρωσης γιά συνολικό διάστημα ενός έτους μετά τον τραυματισμό. Τα αποτελέσματα έδειξαν ότι ο ‘τυπικός’ ρυθμός μετατραυματικής αποκατάστασης αντιστοιχεί σε ταχεία κλινική βελτίωση κατά τη διάρκεια των τριών πρώτων μηνών ακολουθούμενη από ήπιου βαθμού δυσλειτουργία. Ωστόσο σημαντική δυσλειτουργία παραμένει σε 10% των ασθενών ένα έτος μετά τον τραυματισμό. Επίσης, τα αποτελέσματα δείχνουν σημαντικές διαφορές στο βαθμό κατά τον οποίο ο περιορισμός συγκεκριμένων αντικειμενικών κλινικών παραμέτρων αντανακλά το επίπεδο δυσλειτουργίας της πηχεοκαρπικής άρθρωσης. Ακτινολογικά, η μόνιμη απώλεια της παλαμιαίας γωνίας, η κερκιδική βράχυνση και η παρουσία ανωμαλίας της αρθρικής επιφάνειας της πηχεοκαρπικής με αρθρικό ‘βήμα’ τουλάχιστον ενός χιλιοστού σχετίζονται με επιμένοντα συμπτώματα πόνου και δυσλειτουργίας, ενώ δεν υπάρχει εμφανής συσχέτιση μεταξύ του τύπου του κατάγματος και του τελικού λειτουργικού αποτελέσματος. Επιπλέον, ανάλυση δυνάμεων της φυσιολογικής πηχεοκαρπικής άρθρωσης έδειξε φορτίσεις που μπορεί να φθάνουν έως 4,2 φορές το ανυψούμενο βάρος, αντίστροφο συσχετισμό μεταξύ της παλαμιαίας γωνίας του περιφερικού άκρου της κερκίδας και του μέγιστου φορτίου στην κερκιδοκαρπική άρθρωση καθώς και μη σημαντική διαφορά μεταξύ της γωνίας διεύθυνσης του μέγιστου φορτίου της κερκιδοκαρπικής και της παλαμιαίας γωνίας του περιφερικού άκρου της κερκίδας. / Despite the large volume of published literature on the results of management of unstable fractures of the distal radius using closed reduction and minimally invasive fixation there are still significant unanswered questions. More specifically, there is no sufficient evidence about the rate of recovery of the clinical parameters over the post-traumatic period, the final outcome as expressed by the patients using self-assessment scores and the degree that specific radiographic parameters influence the final functional outcome. Furthermore, the correlation between the radiographic parameter of volar tilt of the distal radius and the normal loads in the radiocarpal joint has not been investigated. The present thesis is a prospective study of unstable fractures of the distal radius managed with closed reduction and minimally invasive (percutaneous) fixation. Analysis of radiographic and clinical parameters as well as of patient-rated wrist dysfunction score for one year following injury was carried out. The results showed that a ‘typical’ rate of post-traumatic recovery corresponds to an initial rapid clinical improvement for the first three months followed by mild wrist dysfunction. However, significant dysfunction persists in 10% of patients one year following injury. Furthermore, the results showed significant differences in the degree to which the restriction of specific objective clinical parameters reflected the level of wrist dysfunction. Regarding the radiographic parameters, permanent loss of palmar tilt of the distal radius, radial shortening and the presence of articular incongruency with an articular ‘step off’ of at least 1 mm correlate with persisting pain and dysfunction while there is no obvious correlation between the fracture type and the final functional outcome. Moreover, force analysis in the normal wrist showed loads as high as 4.2 times the lifted weight, a reverse relationship between the angle of palmar tilt of the distal radius and the maximum radiocarpal load as well as a nonsignificant difference between the angle of the maximum radiocarpal force and the angle of palmar tilt of the distal radius.

<p>Scaphoid fracture is most common in young individuals of working age. Without adequate diagnosis and treatment, long-term results are poor. Operative treatment is being recommended increasingly often instead of a long time in cast, although there is no evidence-based support for its superiority.</p><p>The present thesis focuses on diagnostic problems and therapeutic consequences of acute scaphoid fractures and of scaphoid reconstruction when other treatments have failed.</p><p>Simultaneous plain radiographs and computed tomography were done in 97 injured wrists. Structural assessments of plain radiography images were highly predictive with respect to the risk of having a displaced or comminute fracture as diagnosed on computed tomography. Any finding of a gap or step-off > 0.5 mm, the presence of an intermediate fragment or a dorsal lunate tilt of ≥ 15° identified 81 % of fractures that were displaced or comminuted when investigated with computed tomography.</p><p>Eighty-three patients were randomly allocated to and received either nonoperative treatment in cast or operative treatment with the aim of assessing long-term outcome of the two treatment options. Fifty-two of the patients were occupationally active. From an occupational perspective with an early return to work, surgical treatment was superior in individuals with manual employment, and from a health economic perspective conservative treatment was superior in non-manual workers.</p><p>Patients treated for scaphoid fractures generally do well up to 13 years after the injury based on limb-specific outcome scores. No benefits were identified with operative treatment compared to non-operative treatment in cast. On the contrary, there was an increased risk for osteoarthritis in the scaphotrapezial joint in those who were operated.</p><p>The patient-rated long-term results of silicone implant arthroplasty were good, with pain relief and reasonable hand function in many patients up to 20 years after surgery.</p>