Background: Concussion assessments rely on a multifaceted approach where evaluation of balance and postural control plays an important role. Following a concussion, 67% of individuals report dizziness as a persistent symptom and 30% experience balance impairments. Studies incorporating the common Balance Error Scoring System (BESS) tool suggest that these impairments return to pre-injury baselines within ten days of incident. In contrast, however, studies incorporating more advanced posturography methods observe significant differences in balance up to one year following injury. While the BESS is consistently associated with low sensitivity and poor reliability scores, advanced posturography systems using force plates are not practical or accessible in most recreational sports environments. Recently, the Wii Balance Board (WBB) has been identified as a potential force plate proxy. Research confirms that the WBB is both valid and reliable in collecting center of pressure data. Thus, the WBB may be useful for investigating post-concussion balance deficits. Objective: The purpose of this study was to investigate the potential utility of a customized WBB program to assess postural balance in an athletic population. The study aimed to assess change in postural balance using the clinical BESS and WBB assessment tools to evaluate balance at fixed intervals during a regular athletic season and following concussion. Design: Prospective partial cohort. Methods: Balance was assessed at baseline, mid-, and post-season. Individuals who sustained a concussion during the study period were further assessed weekly for four weeks post-injury. Results: No significant differences were observed in raw BESS scores across regular season or post-concussion time points. In contrast, significant differences in several WBB outcome measures were observed. In the single stance condition, COPML worsened by 24% and COPT worsened by 9% between baseline and post-season time points (p=.002 and p=.007). In contrast, participants improved by 14% on a timed dynamic task (p=.003) between baseline and post-season time points. Following concussion, only the WBB dynamic outcome measures were found to be statistically significant. A positive trend was observed post-concussion, suggesting that a learning effect exists with the dynamic WBB program. Conclusion: Study results emphasize the importance of considering the progression of athletic season when interpreting baseline and post-concussion balance measurements. Study results support the use of a quantitative balance assessment, such as with a WBB, to improve measurement of static and dynamic postural balance. / Graduate / 0566 / hilarymcullen@gmail.com

The thesis evaluates the effect of four-week home therapy using stabilometric platform Nintendo Wii Balance Board and tablet with integrated software HomeBalance in patients with brain injury. Software HomeBalance has been developed for the treatment of balance disorders and cognitive function. Manipulating the platform and the tablet may also develop grip and handling abilities of hand, both will be evaluated in this work as well. The theoretical part describes new trends in rehabilitation of cognitive-motor interference, dual-task therapy and therapy using technological equipments. Methods: A total of 9 subjects underwent four weeks of therapy using a therapeutic set HomeBalance. The control group of 12 subjects received therapy without any technological equipment. Patients participated in the initial examination, home therapy and final examination. As an evaluation of the therapy Mini-BESTest, Timed Up and Go test, Montreal cognitive assessment, 9- hole peg test, and also two games from HomeBalance software and questionnaire assessing satisfaction with therapy have been used. Results: After treatment the whole group improved in only two tests evaluated: in Mini- BESTest and the time of diagnostic scene in HomeBalance software. The research group had statistically better results in both tests...

Fall-related injuries in adults over the age of 65 pose an important public health issue especially with an increasing number of older adults living in retirement homes and nursing homes. Safety floors have been developed as an intervention to reduce the risk of these injuries. However, their effects on balance control reactions had never been tested during certain activities of daily living in retirement home dwellers. This research investigated how balance reactions are affected by the mechanical properties of safety flooring in older adults. The safety flooring showed minimal impact on the balance reactions while retaining force attenuation properties. There were two studies as part of this thesis. The purpose of the first study was to determine whether the Nintendo Wii Balance Board (WBB) can be used as an appropriate substitution for a force plate when measuring balance reactions during common tests used to assess balance in older adults. Specifically, I characterized the technical specifications of the WBB and compared them to those of the force plate, showing that the two devices yielded similar responses during balance measures of quiet stance. The second study investigated the effect of two traditional floors and three safety flooring systems on balance control mechanisms (based on changes in underfoot centre of pressure) during sit-to-stand and quiet stance tasks in retirement home-dwellers. The results of this study provided evidence supporting the potential for safety floors to reduce fall-related injury risk without impairing balance and mobility of users. Additional research may want to assess WBB performance during dynamic tasks involving shear forces. The results from this study supports prospective clinical investigations of pilot installations of safety flooring in retirement and nursing home settings to evaluate their real life effects on fall related injuries.

Fall-related injuries in adults over the age of 65 pose an important public health issue especially with an increasing number of older adults living in retirement homes and nursing homes. Safety floors have been developed as an intervention to reduce the risk of these injuries. However, their effects on balance control reactions had never been tested during certain activities of daily living in retirement home dwellers. This research investigated how balance reactions are affected by the mechanical properties of safety flooring in older adults. The safety flooring showed minimal impact on the balance reactions while retaining force attenuation properties. There were two studies as part of this thesis. The purpose of the first study was to determine whether the Nintendo Wii Balance Board (WBB) can be used as an appropriate substitution for a force plate when measuring balance reactions during common tests used to assess balance in older adults. Specifically, I characterized the technical specifications of the WBB and compared them to those of the force plate, showing that the two devices yielded similar responses during balance measures of quiet stance. The second study investigated the effect of two traditional floors and three safety flooring systems on balance control mechanisms (based on changes in underfoot centre of pressure) during sit-to-stand and quiet stance tasks in retirement home-dwellers. The results of this study provided evidence supporting the potential for safety floors to reduce fall-related injury risk without impairing balance and mobility of users. Additional research may want to assess WBB performance during dynamic tasks involving shear forces. The results from this study supports prospective clinical investigations of pilot installations of safety flooring in retirement and nursing home settings to evaluate their real life effects on fall related injuries.

No description available.

Bakgrund: Det finns funktionella tester med varierande svårighetsgrad för att utvärdera patienters balans i kliniken. Dessa tester kan dock endast visa på balansförmåga i grova drag, exempelvis om man kan ställa sig upp från en stol eller klarar att stå på ett ben utan att falla. För mer exakta metoder går det att använda sig utav en kraftplatta. Det har det tidigare undersökts huruvida en Wii Balance Board kan fungera som ett valitt substitut för en standardiserad kraftplatta då denna är lättare och mindre kostsam. Det har dock aldrig undersökts med ett testprotokoll där proprioceptionen hos deltagaren försökt påverkas. Syfte: Öka kunskapen om validiteten för Wii Balance Board i jämförelse med Kistler Force Plate vad gäller mätning av postural kontroll i stillastående med och utan nackrotation via bål och underkropp. Metod: Experimentell metod med 15 deltagare som genomförde tre olika test i stillastående, dels med nacken i neutralposition och dels roterad 45 grader genom att rotera bål och underkropp. Posturala svajet mättes med Wii Balance Board och kraftplatta samtidigt. Skillnader i resultaten uträknades och analyserades sedan med Bland-Altman plots metod och presenterades i grafer. Resultat: Generellt framkom mycket god samstämmighet mellan utrustningarna, dock påvisades anmärkningsvärt större avvikelser för tre av deltagarna. Diskussion: Tekniska problem som har påverkat experimentet har upptäckts under studiens gång och har tagits med för framtida kunskap. Även att standardisera de tester som genomfördes med mer detaljerade och strikta instruktioner för deltagaren att stå stilla är viktigt för att inte få onödigt posturalt svaj. Konklusion: Validiteten för Wii Balance Board bedömer vi som god då resultatet mellan plattorna stämde överens i hög grad. Det är dock viktigt att ta hänsyn till upptäckta avvikelser som går att undvika vid framtida upprepade försök tack vare kunskapen från denna studie.

This work deals with the metods frequency and time frequency analysis of stabilometric signal. In the introroduction is described theory about posturography and posturographic measurment. The work contains describtion of stabilometric parametrs in time domain (1D and 2D parametrs) and in frequency domain. The aim is create review of basic metods used to processing and preprocessing of stabilometric signals and comparing this methods . In work is realized ferquency analysis used Frourier transfrmation and Burg method and time-frequency analysis used Short time Frourier transformation and Wavelet transformation. One part of program is aimed on comparison of this methods.

Behovet för kraftplattor idag växer inom idrotts- och sportsammanhang såväl som inom medicinska sektorn. Problemet med majoriteten av kraftplattorna på marknaden idag är att de är dyra, samt stora och tunga. På Kungliga tekniska högskolans skola för medicinteknik och hälsosystem utvecklades en kraftplatteprototyp med Wii Balance Board i hopp om att vara billigare och kunna användas i medicinskt, terapeutiskt och idrottssyfte. Enligt konstruktören och uppdragsgivaren finns det ett behov att göra om denna prototyp genom att undersöka möjligheten till att använda komponenter som är billiga, tillgängliga för allmänheten men samtidigt är noggrann och pålitlig i mätningarna. I detta arbete undersöks möjligheterna samt konstrueras två prototyper för jämförelse och analys för att säkerställa pålitlighet och noggrannhet.  Två kraftplatteprototyper utvecklades, ena prototypen använde en HX711 som AD- omvandlare mellan lastcellerna på Wii Balance Boarden och ESP32 mikrokontrollern och den andra en AD7124-8 som AD-omvandlare mellan lastcellerna och ESP32 mikrokontrollern. Lastcellerna kopplades till dessa AD-omvandlare som sedan kopplades till en ESP32 mikrokontroller som tog emot datat och presenterade det i Arduino IDE samt i applikationen Blynk. Resultatet av arbetet visade att båda prototyperna är pålitliga och noggranna i viktmätningarna vid låga samplingsfrekvenser, men att AD7124-8 är betydligt mycket mer lämplig i idrott och medicinska syften på grund av dess höga samplingsfrekvens samt filtreringsalternativ för brus då det i dessa sammanhang är viktigt att kunna mäta snabba kraftförändringar. / The need for force plates is increasing today in the sports and medicine industry. The challenges with force plates are the price point and the immobility of them, they are often big and heavy. A force plate prototype with a Wii Balance Board was developed at Royal Institute of Technology’s school for biomedical engineering and health systems with the hope of achieving a cheaper solution that could be used in medical research and the sports industry. According to the constructor of the force plate prototype, there is a need to redo this prototype by doing research of using cheaper and more readily available components but at the same time be precise and trustworthy in measurements. The possibilities are evaluated in this work and two prototypes are constructed.  Two force plate prototypes were constructed, one of them used a HX711 AD-converter between the load cells of the Wii Balance Board and the ESP32 microcontroller and the other prototype used a AD7124-8. The load cells connected to the AD-converters and then to the ESP32 which showed the output values in the serial monitor of Arduino IDE and in the Blynk app. The results of the tests conducted showed that both prototypes provided a reliable and precise measurement of weight at low sample rates. But that the AD7124-8 was considerably more suitable for medicine research and sports research due to its capability to sample at high frequencies and noise filtering options, which is crucial when wanting to detect rapid changes in force.

L’instabilité posturale est fréquente chez les séniors et peut entrainer la chute. La chute chez les séniors est un problème majeur de santé publique. Les chiffres épidémiologiques sont éloquents : une personne sur trois âgées de plus de 70 ans fera une chute dans l’année. Les causes sont multifactorielles : ostéo-articulaire, visuelle, cognitive, vestibulaire…. Dans cette étude, nous nous sommes intéressés à l’évolution de la fonction des récepteurs vestibulaires périphériques avec l’âge et à la perception de rotation à partir des entrées canalaires horizontales (système vestibulaire central et projections vestibulaires corticales). Notre but est d’essayer de comprendre l’implication du vieillissement du système vestibulaire dans l’instabilité posturale des séniors. Au niveau périphérique, nous avons quantifié la fonction des canaux semi-circulaires horizontaux par le test calorique et le vidéo-head impulse test. La fonction des récepteurs otolithiques (utriculaire et sacculaire) a été évaluée par les potentiels évoqués myogéniques recueillis au niveau cervical (voies sacculo-spinales) et oculaire (voies utriculo-oculaires). Au niveau central, la perception de l’entrée vestibulaire canalaire horizontale a été appréciée après irrigation à l’eau chaude du conduit auditif externe en appliquant un score de perception (présence ou absence de sensation rotatoire). Finalement, l’équilibre a été quantifié grâce au test d’organisation sensorielle sur l’Equitest et grâce à un système que nous avons récemment mis au point en collaboration avec le Professeur Curthoys à Sydney, comprenant une Wii Balance Board, un tapis mousse et un masque de réalité virtuelle (Oculus Rift). Les résultats ont montré une diminution des réponses oculaires au test calorique après 70 ans mais une absence de baisse du gain du réflexe vestibulo-oculaire horizontal au vidéo-head impulse test. La fonction otolithique, sacculaire et utriculaire, est altérée avec l’âge quelle que soit la stimulation utilisée (aérienne ou osseuse). La perception de l’entrée vestibulaire canalaire horizontale induite par une stimulation calorique nous a permis de montrer pour la première fois que certains séniors ne percevaient pas la sensation de rotation malgré une réponse oculaire normale (vitesse maximale de la phase lente du nystagmus oculaire supérieure à 15°/s). Dans notre population, nous avons pu ainsi définir deux types de séniors : un groupe présentant une perception de vertige rotatoire et un groupe « négligeant » ne pouvant pas reconstruire une sensation rotatoire à partir des entrées vestibulaires canalaires horizontales. La comparaison de ces deux groupes de séniors appariés sur l’âge ne montre aucune différence de la fonction canalaire horizontale ni de la fonction otolithique sacculaire et utriculaire. Néanmoins, les séniors négligents présentent en majorité des performances anormales (chute ou score diminué) à l’Equitest notamment en conditions 5 et 6. De plus, leur score au DHI est plus élevé relevant ainsi le handicape ressenti par ces séniors à cause de leur instabilité. En conclusion, les troubles de l’équilibre chez certains seniors pourraient résulter en partie d’une dysfonction vestibulaire centrale. Des études ultérieures permettront de déterminer si l’augmentation du seuil de perception rotatoire est un bon facteur prédictif du risque de chute. / Postural instability is common in seniors and can lead to falls which seniors are a major problem for Public Health. Epidemiological studies clearly show the magnitude of this problem: one in three people aged than more 70 years will fall in a year. This is caused by multiple factors including: musculoskeletal, visual, cognition, vestibular… The present study concerns the effect of age on the vestibular peripheral receptors function and on the perception of rotation from horizontal canal inputs (central vestibular processing and vestibular cortical projection). The aim is to try to understand the vestibular mechanisms involved in postural instability and mobility with age. At the peripheral level, the horizontal canal function was assessed using caloric test and video-Head Impulse Test. Otolith function (saccular and utricular) was assessed using vestibular evoked myogenic potentials recorded at cervical level (sacculo-spinal pathways) and at ocular level (utriculo-ocular pathways). At the central level, perception of motion from vestibular horizontal canal inputs was studied after caloric stimulation with warm water using a subjective perceptual score (presence or absence of rotatory vertigo). Finally, postural equilibrium was assessed with the Sensory Organization Test on the Equitest machine and also with a new system developed in collaboration with Prof. Curthoys (Sydney) using a Wii Balance Board, a foam rubber pad and a virtual reality headset (Oculus Rift DK2). Results showed decreased ocular responses induced by caloric stimulation after 70 years of age but healthy horizontal gain of the vestibulo-ocular reflex assessed by video-head impulse testing. The otolithic (saccular and utricular) function is impaired with age for all the stimuli used (air or bone conducted). Perception of motion induced by caloric stimulation (vestibular horizontal canal inputs) allowed us to show for the first time that some seniors are unable to feel the induced rotatory vertigo even with normal ocular responses (peak of the slow phase eye velocity higher than 15°/s). We defined two types of seniors: one senior group having a normal feeling of vertigo and one senior ‘neglect’ group who did not feel any sensation of rotation from horizontal canal inputs. The comparison of these two age-matched groups showed no difference in horizontal canal function, or otolithic function. The majority of the ‘neglect’ seniors with an absence of perception exhibited falls or a decreased score in conditions 5 and 6 during the Equitest. Moreover, their DHI scores were higher, showing the handicap induced by postural instability in these seniors. In conclusion, postural instability and falls in seniors may result from central vestibular impairment (inadequate central processing). A prospective study is needed to determine whether the increase perceptual threshold of rotation could be a good predictor of fall risk in seniors.

[ES] Los desórdenes del equilibrio y la marcha se encuentran entre los déficits motores más frecuentes entre aquellos individuos que han sufrido un ictus. En la clínica, estas habilidades son comúnmente evaluadas mediante herramientas clínicas que, pese a ser generalmente fáciles y rápidas de administrar, adolecen de poca precisión y estar sesgadas. Los sistemas instrumentados de laboratorio existentes para valorar la postura y la marcha resuelven potencialmente estas limitaciones a costa de requerir una preparación previa por parte de los evaluadores, un amplio espacio reservado en la clínica, un elevado tiempo de realización, y tener un coste muy elevado. El desarrollo tecnológico del sector del entretenimiento ha dado lugar en la última década a periféricos, como plataformas de presión y sensores de profundidad, que permiten la interacción mediante movimientos corporales manteniendo un bajo coste y una gran portabilidad y accesibilidad. Estudios iniciales han mostrado un rendimiento de estos dispositivos muy prometedor, y a veces comparable al de sistemas de laboratorio. Sin embargo, la falta de acceso a los sistemas desarrollados, la escasa investigación en personas con ictus y el desconocimiento de las propiedades psicométricas de las pruebas basadas en estos dispositivos en esta población comprometen la relevancia clínica que podrían tener estos sistemas. La hipótesis principal de este trabajo es que plataformas de fuerzas y sensores de profundidad de bajo coste, como la Nintendo Wii Balance Board y la Microsoft Kinect v2, respectivamente, pueden proporcionar información válida para cuantificar y evaluar la postura y la marcha de sujetos que han sufrido un ictus. Durante la presente tesis doctoral, por tanto, se ha llevado a cabo el desarrollo de herramientas de valoración de la postura y la marcha mediante los dispositivos nombrados, se ha posibilitado su acceso libre, se han determinado los valores normativos de las pruebas incluidas en las herramientas desarrolladas, y, finalmente, se ha investigado su sensibilidad, su validez convergente con herramientas clínicas estandarizadas y su fiabilidad inter e intraevaluador. Los resultados obtenidos de la participación de un total de 544 sujetos sanos y 173 sujetos con ictus en los cinco estudios que comprenden este trabajo evidencian que las herramientas desarrolladas permiten caracterizar satisfactoriamente la postura y la marcha de sujetos con ictus con respecto a la de sujetos sanos, poseen una validez convergente con instrumentos variables y coherente, y tienen una fiabilidad inter e intraevaluador excelente para casi todas las pruebas incluidas. Estos hallazgos sugieren que, pese a las limitaciones existentes, las herramientas desarrolladas podrían ser potencialmente usadas como una alternativa de bajo coste a los sistemas de laboratorio existentes para complementar la valoración de la postura y la marcha de sujetos con ictus. / [CA] Els desordres de l'equilibri i la marxa es troben entre els dèficits motors més freqüents entre aquells individus que han patit un ictus. A la clínica, aquestes habilitats són comunament avaluades mitjançant instruments clínics que, tot i ser generalment fàcils i ràpids d'administrar, poden tindre poca precisió i solen estar esbiaixades. Els sistemes instrumentats de laboratori existents per avaluar la postura i la marxa permeten resoldre aquestes limitacions, però requereixen una preparació prèvia per part dels avaluadors, un ampli espai reservat a la clínica, un elevat temps per realitzar cada prova i tenen un cost molt elevat. El desenvolupament tecnològic del sector de l'entreteniment ha donat lloc a plataformes de pressió i sensors de profunditat de baix cost, gran portabilitat i accessibilitat, que permeten la interacció amb entorns virtuals mitjançant moviments corporals. Estudis preliminars han mostrat un rendiment d'aquests dispositius molt prometedor i, de vegades, comparable al de sistemes de laboratori. No obstant això, la falta d'accés a les aplicacions desenvolupades, l'escassa investigació en persones amb ictus i el desconeixement de les propietats psicomètriques de les proves basades en aquests dispositius en aquesta població comprometen la rellevància clínica dels resultats obtinguts. La hipòtesi principal d'aquest treball és que plataformes de forces i sensors de profunditat de baix cost, com la Nintendo Wii Balance Board i la Microsoft Kinect v2, respectivament, poden proporcionar informació vàlida per quantificar i avaluar la postura i la marxa de subjectes amb ictus. Durant la present tesi doctoral, per tant, s'han desenvolupat eines de valoració de la postura i la marxa mitjançant els dispositius anomenats, s'ha possibilitat el seu accés lliure, s'han determinat els valors normatius de les proves incloses en les eines desenvolupades, i, finalment, s'ha investigat la seva sensibilitat, la seva validesa convergent amb instruments clínics estandarditzats i la seua fiabilitat inter i intraavaluador. Els resultats obtinguts de la participació d'un total de 544 subjectes sans i 173 subjectes amb ictus en els cinc estudis que comprenen aquest treball evidencien que les eines desenvolupades permeten caracteritzar satisfactòriament la postura i la marxa de subjectes amb ictus respecte a la de subjectes sans, tenen una validesa convergent amb instruments variable i coherent, i tenen una fiabilitat inter i intraavaluador excel·lent en gairebé totes les proves incloses. Aquestes troballes suggereixen que, tot i les limitacions existents, les aplicacions desenvolupades podrien ser potencialment usades com una alternativa de baix cost als sistemes de laboratori existents per complementar la valoració de la postura i la marxa de subjectes amb ictus. / [EN] Balance and gait disorders are common after stroke. In the clinical setting, these skills are usually assessed using clinical instruments that, despite being generally quick and easy to administer, may have limited accuracy and be biased. Instrumented laboratory-grade systems aimed at assessing posture and gait can potentially overcome these limitations. However, they require specific training to be operated and a long time to perform the assessments, and are usually bulky and expensive. In the last decade, the technological advances in the gaming industry have given rise to low-cost, portable and off-the-shelf devices, such as pressure platforms and depth sensors, which enable interaction with videogames through body movements. Previous research on the performance of these devices has shown promising results, and suggests that some measures could have comparable accuracy to those estimated by laboratory-grade systems. However, the lack of access to the software used in the experiments, the limited research in stroke patients, and the absence of knowledge about the psychometric properties of the assemment tests based on these devices, could limit the clinical relevance of the preliminary findings. The main hypothesis of this thesis is that low-cost force platforms and depth sensors, such as the Nintendo Wii Balance Board and the Microsoft Kinect v2, can provide sensitive, valid and reliable information to quantify and asses the postural control and gait of individuals with stroke, respectively. This work describes the development of two customized applications to assess posture and gait using the devices mentioned above, their publication on a dedicated website, the exploration of the normative values of tests included in the assessment, and, finally, the investigation of the sensitivity, convergent validity with standardized clinical instruments, and their inter- and intra-rater reliability. A total of 544 healthy subjects and 173 individuals with stroke have participated in the five studies that encompass this thesis. The results of these studies showed good sensitivity to motor impairment, variable and consistent convergent validity with clinical instruments, and excellent inter- and intra-rater reliability for almost all the tests examined. All these findings suggest that, despite their limitations, the developed applications interfaced with low-cost force platforms and depth sensors, could be potentially used as a low-cost alternative to instrumented laboratory-grade systems to complement the clinical assessment of the posture and gait of individuals with stroke. / Latorre Grau, J. (2022). Valoración del equilibrio y la marcha mediante sistemas de bajo coste en sujetos con ictus [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/181339