Although gradual changes in air pressure may result in rupture of the tympanic membrane, this most often occurs from a rapid change. Sudden forceful blows on the ear, which seal the external auditory meatus, can result in sufficient increase in the air pressure in the ear canal to rupture the tympanic membrane. The most frequent single cause is a blow on the ear, usually with the open hand. Thi...

Efficient movement underpins all great sporting performances. When performed by an expert, complex movements can appear effortless, almost simple; as Leonardo Da Vinci stated, “simplicity is the ultimate sophistication”. Dynamic control of movement is also central to safe sporting function and is dependent on the sophisticated integration of a range of factors including environment, nature of t...

*This table describes the situation for countries where most sporting participation opportunities are provided through community-based or recreational sporting organisations. It is acknowledged that some countries, like the USA, have sports delivery systems that are more likely to be linked to high schools or university colleges and so some of the opportunities for intervention may be different...

A summary of the evidence linking exercise and osteoarthritis is given in the table. In summary, normal joints appear to tolerate prolonged vigorous low impact exercise without accelerated development of osteoarthritis. The risk of developing osteoarthritis appears to be increased in sporting activities that continually expose normal joints to high levels of impact or torsional loading and in i...