Global decreases in physical activity levels among youth have been observed over the last decade and physical inactivity is one of the major risk factors associated with leading causes of death and disability. Injury has been found to be the most common reason for attrition from lifelong physical activity among young people. This thesis deals with the promotion of physical activity by addressing the prevention of knee injuries among adolescent basketball players. Basketball is currently thought to be one of the fastest growing sports in South Africa, a sport associated with a high knee injury prevalence and consequence of developing early osteoarthritic changes. There are no published reports on knee injury prevalence among African youth, nor is there a national policy on injury prevention as a mechanism for promoting healthy activity. This thesis reports on several interlinked studies which established injury prevalence and mechanisms, investigating the biomechanics of a major injury mechanism, designed and laboratory tested preventative strategy, and then applied this strategy in a pilot field study. / The first stage of this study involved a retrospective survey of young South African basketball players (n=458). A questionnaire captured information on injuries sustained during the previous season. The probability of sustaining a knee injury was significantly greater than sustaining an injury to another body part or no injury combined (OR: 1.3:95% CL 1.1-1.5). The most common injury mechanism among both boys and girls was landing badly from a jump and approximately one third of the knee injuries (37.5%) were sustained as a result of landing badly. / The second stage of the study, a biomechanical analysis of landing strategies of matched knee injured and uninjured adolescent basketball players (n=22) was conducted using a three-dimensional, six-camera Vicon motion analysis system and force plate. The injured and uninjured players were matched for gender, age, anthropometrics, basketball experience and had to play for the same club. A strong positive correlation (0.49: p<0.01) was found between the maximum ground reaction force and the average injury score of the case subjects. The control players had significantly deeper knee flexion angles than the cases on landing (p=0.01). Injured players also demonstrated significantly less eccentric activity on landing compared to the uninjured players (p<0.01). / The third stage of the study was to develop a neuromuscular exercise program to prevent injuries from landing, based on the biomechanical analysis of the landing data. Currently these types of exercise programs have the most promising evidence in the prevention of knee injuries. The rationale of these programs are based on improving feed-forward mechanisms of motor control, thereby decreasing the motor response time, enabling dynamic joint stability to prevent injuries during high speed dynamic tasks such as landing. Biomechanical validation of the resultant exercise program suggested that it would be effective in improving landing technique of uninjured male adolescent basketball players with respect to reducing peak ground reaction forces (p<0.01), improved knee flexion angles (p<0.01) and improved negative work (p<0.01). / The final stage of the project was to employ health promotion principles in an on-field validation of the exercise program and highlighted the complexities of introducing such a program into real-life training situations. The preliminary results from this aspect of the study demonstrated a decrease in knee injury prevalence. The importance of qualitative information in implementing preventative strategies in ensuring the success of the program implementation and compliance from players, coaches and players was also highlighted. / This study proposes recommendations for preventing knee injuries in adolescent South African basketball players and provides ideas for future research into injury prevention in young sports players. / Thesis (PhD)--University of South Australia, 2004.
| Identifer | oai:union.ndltd.org:ADTP/267562 |
| Creators | Louw, Quinette |
| Source Sets | Australiasian Digital Theses Program |
| Language | English |
| Detected Language | English |
| Rights | copyright under review |
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