Australian rules football injuries
Australian rules football is a sport known for its high level of physical body contact compared to other sports such as soccer and basketball. High impact collisions can occur from any direction, although deliberate collisions from front-on (known specifically as a "shirtfront" when the contact is body-on-body). In addition, players typically wear no protective padding of any kind except for a mouthguard (unlike the full-body gear in gridiron football codes or the shinguards in soccer). As such, injury rates tend to be high. Soft tissue injuries are the most frequent, including injuries  to the thighs and calf muscles. Osteitis pubis is a condition which particularly affects Australian rules footballers. Injuries to the knee, ankle and shoulders are also common. Hospital treated injuries account for 40 percent of all injuries. Knee reconstructions are among the career threatening injuries for professional and amateur players. Full contact play with the potential to be tackled or bumped from any angle means that the risk of a knee being twisted or caught on a dangerous angle is high. While many players choose not to wear protective padding, players do occasionally suffer head injury resulting in loss of  consciousness however spinal injury is extremely uncommon and comparatively much lower than rugby football. In recent years the AFL has commissioned official studies as well as introduced new rules and precautions aimed at reducing the number and severity of injuries in the sport. The high levels of injuries that take place during games of football are so much that not only during a players' career are they susceptible to injuries, but the effects afterwards are detrimental to their health. One example of a current player (as of 2005) that has suffered a large share of injuries is Essendon champion James  Hird, who has suffered virtually every injury imaginable. In a study conducted recently of 413 retired VFL/AFL footballers, common problems amongst the group in old age included arthritis, hip replacements (including Kevin Sheedy, who has had two operations on his hip within a short period of time), and low ability to perform sport-based activities. Steven Febey recently spoke out in "Good Weekend" (the magazine of the Fairfax newspaper network) detailing that his emphasis on fitness during his career had been cancelled out after his retirement, when the onset of injuries during his football career began to take their  toll. The AFL Players' Association is working on initiatives to set up a player welfare fund for after footballers' retirements. Serious or career threatening injury cases in the AFL. The following is a list of incidents in professional Australian Rules which required immediate hospitalisation or threatened the career or a player.