A Dissertation submitted to the Department of Physiology, University of Witwatersrand, Johannesburg in fulfilment of the requirements for the degree of Master of science in Medicine. / The management and prevention of ankle sprains had been a topic of controversy in the sport medical literature to date, with various rehabilitative and preventative protocols having been suggested. In part one of this study, a relatively new rehabilitative device, the Cybex II Dynamometer,was used to determine whether the rehabilitation period of ankle sprain injuries could be reduced in recently injured patients. In part two, the Cybex II Dynamometer was used in conjunction with other training techniques in a preventative trial of first league volleyball players, to see whether the incidence of ankle sprains (which is particularly high in this population group) could be reduced. Although the experimental group was discharged almost 35 percent sooner than the control group in part one, the difference was not found to be statistically significant. In part two the preventative measures resulted in a notable difference in the incidence of injuries (32 percent in the control group compared to 11 percent in the experimental, group). Differences were just not statistically significant (p=O.059). / Andrew Chakane 2018

by Yeung Ming San, Josephine. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves 161-172). / ABSTRACT --- p.1 / Chapter I. --- INTRODUCTION --- p.4 / Chapter II. --- LITERATURE REVIEW --- p.12 / Chapter 2.1 --- Functional Anatomy of Ankle and Subtalar Joint --- p.12 / Chapter 2.1.1 --- Bony Configuration --- p.12 / Chapter 2.1.2 --- Axis of Motion --- p.13 / Chapter 2.1.3 --- Lateral Ligaments --- p.13 / Chapter 2.1.4 --- Ankle Musculature --- p.13 / Chapter 2.2 --- Biomechanics of Ankle Ligaments --- p.14 / Chapter 2.2.1 --- Characteristics of Lateral Ligaments of the Ankle --- p.15 / Chapter 2.2.1.1 --- Ligaments for Stability --- p.15 / Chapter 2.2.1.2 --- Ligaments Properties to Loading --- p.15 / Chapter 2.3 --- Lateral Ankle Ligaments Injuries --- p.17 / Chapter 2.3.1 --- Etiology --- p.17 / Chapter 2.3.2 --- Definition of Sprain --- p.18 / Chapter 2.3.3 --- Classification of Inversion Ankle Sprain --- p.18 / Chapter 2.3.4 --- Diagnosis of Lateral Ligaments Injury --- p.19 / Chapter 2.3.4.1 --- Anterior Draw Test --- p.19 / Chapter 2.3.4.2 --- Talar Tilt Test --- p.21 / Chapter 2.3.4.3 --- Anthrogram --- p.21 / Chapter 2.3.4.4 --- Controversies in Various Diagnostic Methods for Lateral Ankle Ligaments Injury --- p.21 / Chapter 2.3.5 --- Orthopedic Management of Inversion Ankle Sprain --- p.22 / Chapter 2.3.5.1 --- Operative Method --- p.22 / Chapter 2.3.5.2 --- Conservative Method --- p.23 / Chapter 2.4 --- Rehabilitation of Inversion Ankle Injury --- p.24 / Chapter 2.4.1 --- Residual Problems Resulted from Inversion Ankle Injury --- p.24 / Chapter 2.4.1.1 --- Epidemiology --- p.24 / Chapter 2.4.1.2 --- Muscle Weakness --- p.25 / Chapter 2.4.1.3 --- Proprioception --- p.27 / Chapter 2.4.1.4 --- Peroneal Muscle Reaction Time --- p.29 / Chapter 2.4.1.5 --- Muscle Tightness --- p.30 / Chapter 2.4.2 --- Rehabilitation Training --- p.31 / Chapter 2.4.2.1 --- Muscle Training --- p.31 / Chapter 2.4.2.2 --- Proprioception Training --- p.32 / Chapter 2.4.2.3 --- Other Training --- p.32 / Chapter 2.5 --- Strength Training --- p.33 / Chapter 2.5.1 --- Effects of Strength Training --- p.33 / Chapter 2.5.1.1 --- On Muscle --- p.33 / Chapter 2.5.1.2 --- On Nervous System --- p.33 / Chapter 2.5.1.3 --- On Ligaments --- p.34 / Chapter 2.5.2 --- Isokinetic Training --- p.34 / Chapter III. --- METHODOLOGY --- p.39 / Chapter 3.1 --- Epidemiological Survey --- p.42 / Chapter 3.1.1 --- Design of Questionnaire --- p.42 / Chapter 3.1.2 --- Pilot Study --- p.43 / Chapter 3.1.3 --- Survey --- p.44 / Chapter 3.2 --- Isokinetic Evaluation for Normal Non-injured Ankle --- p.45 / Chapter 3.2.1 --- Subjects --- p.45 / Chapter 3.2.2 --- Equipment --- p.46 / Chapter 3.2.3 --- Testing Procedure --- p.51 / Chapter 3.3 --- Evaluation for Ankle with Inversion Sprain --- p.59 / Chapter 3.3.1 --- Initial Evaluation --- p.60 / Chapter 3.3.1.1 --- Criteria for Subjects --- p.60 / Chapter 3.3.1.2 --- Interview of Subjects --- p.61 / Chapter 3.3.1.3 --- Testing Procedure --- p.61 / Chapter 3.3.2 --- Training Program --- p.66 / Chapter 3.3.2.1 --- Subjects --- p.66 / Chapter 3.3.2.2 --- Various Methods of Training or Exercise --- p.67 / Chapter 3.3.2.3 --- Isokinetic Exercise Protocol for Ankle --- p.69 / Chapter 3.3.2.4 --- Design of Training Protocol --- p.71 / Chapter 3.3.3 --- Second Evaluation --- p.73 / Chapter 3.3.3.1 --- Subject --- p.73 / Chapter 3.3.3.2 --- The Retest --- p.73 / Chapter 3.4 --- Data Analysis --- p.74 / Chapter IV. --- RESULTS --- p.75 / Chapter 4.1 --- Epidemiological Study --- p.75 / Chapter 4.1.1 --- Athletes' Personal Data --- p.75 / Chapter 4.1.2 --- Athletes' Injury Data --- p.82 / Chapter 4.1.3 --- Residual Problems in Ankle Sprains --- p.84 / Chapter 4.2 --- Isokinetic Evaluation for Normal Non-injured Ankle --- p.89 / Chapter 4.2.1 --- Subjects Data --- p.89 / Chapter 4.2.2 --- Range of Active and Passive Ankle Dorsiflexion --- p.89 / Chapter 4.2.3 --- Muscular Parameters Used for Data Analyzing --- p.90 / Chapter 4.2.4 --- Comparing Muscular Parameters between Dominant and Non-dominant Ankle of Normal Subjects --- p.90 / Chapter 4.2.5 --- Comparing Muscular Parameters between Male and Female Normal Subjects --- p.94 / Chapter 4.2.6 --- Torque Ratio and Work Ratio --- p.98 / Chapter 4.3 --- Evaluation for Ankles with Inversion Sprain --- p.102 / Chapter 4.3.1 --- Initial Evaluation --- p.102 / Chapter 4.3.1.1 --- Subjects Data --- p.102 / Chapter 4.3.1.2 --- Anterior Draw Sign --- p.103 / Chapter 4.3.1.3 --- Range of Motion --- p.103 / Chapter 4.3.1.4 --- Ankle Functional Rating Scale --- p.104 / Chapter 4.3.1.5 --- Isokinetic Evaluation --- p.104 / Chapter 4.3.2 --- Second Evaluation --- p.116 / Chapter 4.3.2.1 --- Subjects Data --- p.116 / Chapter 4.3.2.2 --- Comparing the Initial and Second Evaluation Ankle Functional Rating Scale --- p.117 / Chapter 4.3.2.3 --- Comparing Initial and Second Evaluation for Isokinetic Parameters of the Ankle --- p.118 / Chapter 4.3.3 --- Correlation of Various Isokinetic Parameters of the Ankle with Ankle Functional Rating Score --- p.124 / Chapter V. --- DISCUSSION --- p.127 / Chapter 5.1 --- Epidemiological Study --- p.127 / Chapter 5.2 --- Evaluation for Normal Non-injured Ankle --- p.132 / Chapter 5.3 --- Evaluation for Ankle with Inversion Sprain --- p.141 / Chapter 5.4 --- Isokinetic Rehabilitation --- p.148 / Chapter 5.5 --- Limitations and Future Direction of Research --- p.153 / Chapter VI. --- CONCLUSION --- p.156 / Chapter VII. --- REFERENCE --- p.161 / APPENDIX I --- p.i / APPENDIX II --- p.vi / APPENDIX III --- p.viii / APPENDIX IV --- p.xiii

Recorded on July 27, 2007 by Eugene Barsky, Physiotherapy Outreach Librarian, UBC

Thesis (Ph.D.)--Virginia Commonwealth University, 2010. / Prepared for: Dept. of Biomedical Engineering. Title from title-page of electronic thesis. Bibliography: leaves 149-157.

Mok, Kam Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 36-44). / Abstracts in English and Chinese. / Abstract --- p.ii / Chinese abstract --- p.iii / Acknowledgement --- p.iv / Table of contents --- p.V / List of figures --- p.vii / List of tables --- p.viii / Chapter Chapter 1: --- Introduction --- p.1 / Chapter Chapter 2: --- Review of literature --- p.3 / Chapter 2.1 --- Why prevent ankle ligamentous sprain? --- p.3 / Chapter 2.2 --- A sequence of injury prevention --- p.4 / Chapter 2.3 --- Biomechanical approaches in defining injury mechanism --- p.5 / Chapter 2.4 --- Injury mechanism of ankle ligamentous sprain in sports --- p.6 / Chapter 2.5 --- Model-Based Image-Matching motion analysis --- p.7 / Chapter Chapter 3: --- Development of an ankle joint Model-Based Image-Matching motion analysis technique --- p.9 / Chapter 3.1 --- Introduction --- p.9 / Chapter 3.2 --- Materials and method --- p.10 / Chapter 3.2.1 --- Cadaver test --- p.10 / Chapter 3.2.2 --- Model-Based Image-Matching motion analysis --- p.12 / Chapter 3.2.3 --- Statistical analysis --- p.14 / Chapter 3.3 --- Results --- p.15 / Chapter 3.3.1 --- Validity --- p.15 / Chapter 3.3.2 --- Intra-rater reliability --- p.16 / Chapter 3.3.3 --- Inter-rater reliability --- p.17 / Chapter 3.4 --- Discussion --- p.17 / Chapter 3.5 --- Conclusion --- p.21 / Chapter Chapter 4: --- Biomechanical motion analysis on ankle ligamentous sprain injury cases --- p.22 / Chapter 4.1 --- Introduction --- p.22 / Chapter 4.2 --- Materials and method --- p.24 / Chapter 4.2.1 --- Case screening --- p.24 / Chapter 4.2.2 --- Model-Based Image-Matching motion analysis --- p.24 / Chapter 4.3 --- Results --- p.28 / Chapter 4.3.1 --- High Jump Injury --- p.28 / Chapter 4.3.2 --- Field hockey Injury --- p.28 / Chapter 4.3.3 --- Tennis Injury --- p.29 / Chapter 4.4 --- Discussion --- p.30 / Chapter 4.5 --- Conclusion --- p.34 / Chapter Chapter 5: --- Summary and future development --- p.35 / References --- p.36 / List of publications --- p.42 / List of presentations at international and local conference --- p.43 / List of Awards --- p.44

Chan, Yue Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 36-40). / Abstracts in English and Chinese. / Abstract --- p.i / Chinese abstract --- p.ii / Acknowledgement --- p.iii / Table of Contents --- p.iv / List of figures --- p.vi / List of tables --- p.vii / Chapter Chapter 1: --- Introduction --- p.1 / Chapter Chapter 2: --- Review of literature --- p.4 / Chapter 2.1 --- Chapter introduction --- p.4 / Chapter 2.2 --- Anatomy and kinematics of the ankle --- p.4 / Chapter 2.3 --- Epidemiology of ankle sprain --- p.6 / Chapter 2.4 --- Grading system for classification of ankle sprain --- p.7 / Chapter 2.5 --- Previous measures of protecting ankle from sprain injury --- p.7 / Chapter 2.6 --- Usage of motion sensors in human motion detection --- p.9 / Chapter Chapter 3: --- A mechanical supination sprain simulator for studying ankle supination sprain kinematics --- p.11 / Chapter 3.1 --- Chapter Introduction --- p.11 / Chapter 3.2 --- Methods --- p.12 / Chapter 3.3 --- Results --- p.17 / Chapter 3.4 --- Discussion --- p.17 / Chapter Chapter 4: --- Identification of simulated ankle supination sprain from other normal motions by gyrometers and accelerometers --- p.19 / Chapter 4.1 --- Chapter introduction --- p.19 / Chapter 4.2 --- Methods --- p.20 / Chapter 4.2.1 --- Data collection --- p.20 / Chapter 4.2.2 --- Support Vector Machine for classification of human motion --- p.22 / Chapter 4.2.3 --- Training the Support Vector Machine --- p.23 / Chapter 4.2.4 --- Support Vector Machine verification --- p.24 / Chapter 4.2.5 --- Choose the optimal position of motion sensor --- p.25 / Chapter 4.3 --- Results --- p.25 / Chapter 4.4 --- Discussion --- p.29 / Chapter Chapter 5: --- Summary and future development --- p.34 / References --- p.36 / List of publications --- p.41 / List of presentations at international and local conferences --- p.41 / Appendix I: --- p.42 / Related publication: / "Chan, Y. Y., Fong, D. T. P., Yung, P. S. H., Fung, K. Y., & Chan, K. M (1998). A mechanical supination sprain simulator for studying ankle supination sprain kinematics. Journal of Biomechanics. 41(11), 2571-2574." / Appendix II: --- p.46 / Ethical approval of the investigation of ankle torque and motion signal pattern in foot segment during simulate sprain and other motion

O entorse de tornozelo está entre as lesões mais comuns durante as atividades esportivas. Apesar de extensas pesquisas clínicas e experimentais, a recorrência da lesão permanece alta. A prevenção do entorse de tornozelo só é possível uma vez que os fatores de risco forem identificados. Alterações no posicionamento do pé, déficits proprioceptivos, frouxidão mecânica lateral do tornozelo e déficits de força muscular são os possíveis fatores de risco para o entorse de tornozelo, mas os seus verdadeiros mecanismos ainda não estão esclarecidos. O entendimento desses mecanismos pode auxiliar os profissionais de saúde, principalmente os fisioterapeutas, a elaborar um programa de tratamento mais direcionado, levando a uma reabilitação mais eficaz. O objetivo deste estudo foi avaliar os fatores mecânicos e eletromiográficos associados ao entorse de tornozelo. Trinta e duas atletas de basquetebol e voleibol do gênero feminino (16.06±0.8 anos; 67.63±8.17 kg; 177.8±6.47 cm) participaram do estudo. As atletas foram separadas em dois grupos: um grupo controle, sem sintomas (29 tornozelos), e atletas que tinham sofrido entorse de tornozelo (29 tornozelos). A avaliação do alinhamento do retropé foi realizada por meio de fotogrametria, pelo programa SAPO® v.0.63, com as atletas em pé. A propriocepção, o torque passivo gerado pela resistência do movimento do tornozelo e a força muscular foram avaliados no dinamômetro isocinético Biodex®, e a atividade eletromiográfica de superfície pelo sistema Noraxon®. O senso de posição articular (15° inversão, 0°, 15° eversão), a cinestesia (2°/s, 4°/s, 10º/s) e o torque passivo (5°/s, 10º/s, 20°/s) foram avaliados durante os movimentos passivos de eversão e inversão. O torque eversor e inversor foi testado isometricamente (15° inversão, 0°, 15° eversão), concentricamente e excentricamente (60°/s, 180°/s, 300°/s), simultaneamente à medida do sinal eletromiográfico dos músculos fibular longo e tibial anterior. Os dados foram analisados pela ANOVA de dois e três fatores e teste post hoc Tukey. Os resultados mostraram que o alinhamento do retropé e o senso de posição não estão associados ao entorse de tornozelo em atletas do gênero feminino. Os resultados do grupo com entorse do tornozelo que indicaram diferenças significativas em relação ao grupo controle foram: atraso no tempo de percepção do movimento, menor torque passivo e menor torque isométrico e isocinético concêntrico. Além disso, a atividade eletromiográfica do músculo fibular longo e tibial anterior, durante o teste isocinético concêntrico, foi menor no grupo com entorse do tornozelo. Baseado nesses resultados, as atletas que tiveram entorse de tornozelo apresentaram déficits proprioceptivos, frouxidão mecânica e fraqueza muscular. / Ankle sprain are among the most common injuries during athletic activities. Despite extensive clinical and basic science research, the recurrence rate remains high. Prevention of ankle sprain is only possible once risk factors had been identified. Changes in foot positioning, impaired proprioception, mechanical lateral ankle laxity and muscle strength deficits are possible ankle sprain risk factors, but its real mechanisms remain unclear. Understanding such mechanisms will help health professionals, mainly physiotherapists, identify where to focus treatment efforts, leading to more effective rehabilitation. The aim of this study was to evaluate mechanical and electromyographic factors associated with ankle sprain. Thirty-two basketball and volleyball female athletes (16.06±0.8 years; 67.63±8.17 kg; 177.8±6.47 cm) participated in this study. Their ankles were divided into two groups: a symptom-free control group (29) and athletes who had suffered ankle sprain (29). Assessment of hindfoot alignment was performed by means of photogrammetry SAPO® v.0.63 software, with the athletes standing up. The proprioception, resistive torque at maximum passive ankle movement and muscle strength were assessed on the Biodex® isokinetic dynamometer and the surface electromyographic activity through the Noraxon® system. The joint position sense (15° inversion, 0°, 15° eversion), kinesthesia (2°/s, 4°/s, 10°/s) and resistive torque (5°/s, 10°/s, 20°/s), were evaluated during passive ankle inversion and eversion movements. Evertor and invertor torques were assessed isometrically (15° inversion, 0°, 15° eversion), concentrically and eccentrically (60°/s, 180°/s, 300°/s) measured simultaneously with electromyographic signal of peroneus longus and tibialis anterior muscles. The data were analyzed using 2 and 3-way ANOVA with Tukeys test for post hoc analysis. The results showed that the hindfoot alignment and the joint position sense were not associated with the ankle sprain in female athletes. The results of the ankle sprain group showed significant differences from the control group: delay in the time to detection passive motion, lower resistive torque and lower isometric and concentric torque. In addition, the electromyographic activity of peroneus longus and tibialis anterior muscles during isokinetic concentric test was lower in the ankle sprain group. Based on these results, the athletes who had ankle sprain have proprioceptives deficits, mechanical laxity and muscle weakness.

After investigating the injury mechanism, this dissertation aims to design an intelligent sprain-free sports shoe for the prevention of sport-related ankle sprain injury. It consists of a three-step mechanism: (1) Sensing, (2) Identification, and (3) Correction. The progress of this dissertation covers two options of sensing and identification. The first option is to monitor the ankle spraining motion with the ankle inversion angle. A method to employ two tiny inertial and magnetic sensors at the shank and foot segment is adopted as the sensing system. A laboratory study is conducted to obtain ankle inversion magnitude and velocity during various sport motions. Together with the article kinematics reported in the accidental sprain case report, a standard for identifying ankle sprain is established. The second option is to monitor the ankle spraining motion with the ankle supination torque. A feasible method to estimate the complete ground reaction forces with the information from pressure insoles is presented. Then, a tiny in-shoe three-pressure-sensor system is devised to monitor the ankle supination torque during sport motions. With the information of failure torque at the ankle joint reported by previous cadaveric study, an identification system of the ankle supination torque is devised. / Ankle sprain injury is the most common single type of sport-related musculoskeletal trauma which causes rupture and tear to the anterior talofibular ligament and ankle instability. In this dissertation, a new paradigm, "Orthopaedic Sport Biomechanics", is proposed to present the role of biomechanics in the practice of orthopaedics sports medicine, including the analysis of injury mechanism, and the design of prophylactic equipment for injury prevention. To directly investigate the injury, a case report of an accidental injury event in laboratory is presented. It was found that an internally rotated ankle orientation at foot strike may predispose the ankle joint to a supination sprain injury, by triggering lateral drift of the rearfoot and the subsequent vigorous inversion. At injury, the ankle joint reached an inversion of 48 degrees and an internal rotation of 10 degrees. / Future studies on the sensing and identification process, the correction, and the final evaluation are suggested. We hope that we could really invent the sprain-free shoe to help reducing the incidence of ankle sprain injury in sports in future. / Fong, Tik Pui Daniel. / Adviser: Kai-Ming Chan. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3635. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 102-127). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

O entorse de tornozelo está entre as lesões mais comuns durante as atividades esportivas. Apesar de extensas pesquisas clínicas e experimentais, a recorrência da lesão permanece alta. A prevenção do entorse de tornozelo só é possível uma vez que os fatores de risco forem identificados. Alterações no posicionamento do pé, déficits proprioceptivos, frouxidão mecânica lateral do tornozelo e déficits de força muscular são os possíveis fatores de risco para o entorse de tornozelo, mas os seus verdadeiros mecanismos ainda não estão esclarecidos. O entendimento desses mecanismos pode auxiliar os profissionais de saúde, principalmente os fisioterapeutas, a elaborar um programa de tratamento mais direcionado, levando a uma reabilitação mais eficaz. O objetivo deste estudo foi avaliar os fatores mecânicos e eletromiográficos associados ao entorse de tornozelo. Trinta e duas atletas de basquetebol e voleibol do gênero feminino (16.06±0.8 anos; 67.63±8.17 kg; 177.8±6.47 cm) participaram do estudo. As atletas foram separadas em dois grupos: um grupo controle, sem sintomas (29 tornozelos), e atletas que tinham sofrido entorse de tornozelo (29 tornozelos). A avaliação do alinhamento do retropé foi realizada por meio de fotogrametria, pelo programa SAPO® v.0.63, com as atletas em pé. A propriocepção, o torque passivo gerado pela resistência do movimento do tornozelo e a força muscular foram avaliados no dinamômetro isocinético Biodex®, e a atividade eletromiográfica de superfície pelo sistema Noraxon®. O senso de posição articular (15° inversão, 0°, 15° eversão), a cinestesia (2°/s, 4°/s, 10º/s) e o torque passivo (5°/s, 10º/s, 20°/s) foram avaliados durante os movimentos passivos de eversão e inversão. O torque eversor e inversor foi testado isometricamente (15° inversão, 0°, 15° eversão), concentricamente e excentricamente (60°/s, 180°/s, 300°/s), simultaneamente à medida do sinal eletromiográfico dos músculos fibular longo e tibial anterior. Os dados foram analisados pela ANOVA de dois e três fatores e teste post hoc Tukey. Os resultados mostraram que o alinhamento do retropé e o senso de posição não estão associados ao entorse de tornozelo em atletas do gênero feminino. Os resultados do grupo com entorse do tornozelo que indicaram diferenças significativas em relação ao grupo controle foram: atraso no tempo de percepção do movimento, menor torque passivo e menor torque isométrico e isocinético concêntrico. Além disso, a atividade eletromiográfica do músculo fibular longo e tibial anterior, durante o teste isocinético concêntrico, foi menor no grupo com entorse do tornozelo. Baseado nesses resultados, as atletas que tiveram entorse de tornozelo apresentaram déficits proprioceptivos, frouxidão mecânica e fraqueza muscular. / Ankle sprain are among the most common injuries during athletic activities. Despite extensive clinical and basic science research, the recurrence rate remains high. Prevention of ankle sprain is only possible once risk factors had been identified. Changes in foot positioning, impaired proprioception, mechanical lateral ankle laxity and muscle strength deficits are possible ankle sprain risk factors, but its real mechanisms remain unclear. Understanding such mechanisms will help health professionals, mainly physiotherapists, identify where to focus treatment efforts, leading to more effective rehabilitation. The aim of this study was to evaluate mechanical and electromyographic factors associated with ankle sprain. Thirty-two basketball and volleyball female athletes (16.06±0.8 years; 67.63±8.17 kg; 177.8±6.47 cm) participated in this study. Their ankles were divided into two groups: a symptom-free control group (29) and athletes who had suffered ankle sprain (29). Assessment of hindfoot alignment was performed by means of photogrammetry SAPO® v.0.63 software, with the athletes standing up. The proprioception, resistive torque at maximum passive ankle movement and muscle strength were assessed on the Biodex® isokinetic dynamometer and the surface electromyographic activity through the Noraxon® system. The joint position sense (15° inversion, 0°, 15° eversion), kinesthesia (2°/s, 4°/s, 10°/s) and resistive torque (5°/s, 10°/s, 20°/s), were evaluated during passive ankle inversion and eversion movements. Evertor and invertor torques were assessed isometrically (15° inversion, 0°, 15° eversion), concentrically and eccentrically (60°/s, 180°/s, 300°/s) measured simultaneously with electromyographic signal of peroneus longus and tibialis anterior muscles. The data were analyzed using 2 and 3-way ANOVA with Tukeys test for post hoc analysis. The results showed that the hindfoot alignment and the joint position sense were not associated with the ankle sprain in female athletes. The results of the ankle sprain group showed significant differences from the control group: delay in the time to detection passive motion, lower resistive torque and lower isometric and concentric torque. In addition, the electromyographic activity of peroneus longus and tibialis anterior muscles during isokinetic concentric test was lower in the ankle sprain group. Based on these results, the athletes who had ankle sprain have proprioceptives deficits, mechanical laxity and muscle weakness.

O objetivo desta pesquisa foi caracterizar o último episódio de entorse de tornozelo em atletas de voleibol de alto rendimento. Participaram inicialmente deste estudo, entre os meses janeiro de 2003 e março de 2004, 114 atletas, do sexo masculino, atuantes na categoria adulta de 9 equipes, todas participantes da Divisão Especial ou Primeira Divisão do Campeonato Paulista de Voleibol. Dos 114 atletas inicialmente analisados, 21 relataram não ter sofrido nenhuma lesão nos tornozelos, portanto, seguindo os critérios de exclusão, foram analisados 93 episódios de última entorse de tornozelo de 93 atletas. Os mesmos foram entrevistados de maneira oral e individual pelo pesquisador executante, seguindo a seqüência do questionário pré-estabelecido. Foi encontrada diferença significante na correlação entre a fase da competição e a causa da entorse bem como na relação entre a posição de atuação do atleta e o fundamento realizado no momento da lesão. Apesar dos demais itens propostos nos objetivos não terem apresentado diferença significante, os resultados indicaram que 74,2% das entorses ocorreram por mecanismo de inversão, sendo, que a maioria das recidivas também ocorreram durante este movimento. A posição oposto foi a mais acometida e o fundamento bloqueio foi o que mais ocasionou entorses. Quanto as possíveis causas do trauma, a maioria aconteceu com a participação de um segundo atleta e a fase em que mais ocorreu lesão foi o treinamento. Referente à prevenção, após o último episódio de lesão, houve um aumento no uso de proteção do tipo tornozeleira, atingindo 68,9% do total de atletas. / The purpose of this research is to characterize the last ankle sprain episode occurred with volleyball high performance athletes. From January 2003 to March 2004, 114 male athletes from 9 adult category teams of the Special and First Division of São Paulo State Volleyball Championship participated of this study. From the 114 athletes analyzed, 21 have reported no ankle sprains, thus, the last 93 episodes of ankle sprain from 93 athletes were analysed following exclusion criteria. They have been individually interviewed by the researcher, following a pre-established questionnaire. A meaningful difference was found in the correlation between the competition phase and the ankle sprain cause, as well as, in the relation between the athlete?s acting position and the movement made at the injury moment. Despite the other items proposed in the objectives have not presented any significant difference, the results indicated that 74,2% of the injuries occurred due the inversion mechanism and most of the repeated ankle sprains have also occurred during this movement. The opposite position was the most affected and the blocking movement was the one that caused the most injuries. As regards the possible causes of the injuries, most of the sprains occurred when a second athlete was involved and most of them during the training period. Concerning prevention, the use of the safety protection, such as orthesis, has increased reaching 68,9% of the total athletes.