Knee injuries are the most common injury in football. The rate of injuries during games is 8.5x greater than the rate in practices, but since players have 9 or 10x more practices than games during a season, practice injuries are about as common as game time injuries.
A football injury study was done for the 1986 and 1987 football seasons. There was a combined total of 6,229 players in the study, with 445,856 Athletic Exposures (AEs). An AE is a practice session or a game.
Of the AEs, 410,165 (92.0%) occurred in practices and 35,691 in games (8.0%). A total of 2,820 injuries were reported, for an overall injury rate of 6.32/1,000 AEs, or 45.27/100 players.
The rate in practices was 3.93/1,000 AEs; in games, 33.68/1,000 AEs. Thus the injury rate was 8.6 times higher in games than in practices (in which 57.1% of total injuries occurred). This major difference in injury rate between competition and practice is consistent with most other sports that have been studied (1-3).
Anatomic site - Total Injuries - Injuries/1,000 AEs
Knee - 522 - 1.17
Ankle - 446 - 1.00
Shoulder - 297 - 0.67
Quadriceps - 180 - 0.40
Head - 155 - 0.35
Neck - 133 - 0.30
Hamstring - 130 - 0.29
Lower back - 108 - 0.24
Finger(s) - 85 - 0.19
Pelvis, hip - 84 - 0.19
Lower leg - 81 - 0.18
Hand - 58 - 0.13
Foot - 54 - 0.12
Elbow - 53 - 0.12
Ribs - 52 - 0.12
Groin - 51 - 0.11
Toe(s) - 46 - 0.10
Thumb - 38 - 0.09
Wrist - 26 - 0.06
Clavicle - 24 - 0.05
Other - 24 - 0.05
Heel/Achilles tendon - 23 - 0.05
Forearm - 17 - 0.04
Patella - 17 - 0.04
Eye(s) - 13 - 0.03
Sternum - 13 - 0.03
Chin - 12 - 0.03
Upper back - 12 - 0.03
Nose - 11 - 0.02
Stomach - 9 - 0.02
Upper arm - 7 - 0.02
Spine - 7 - 0.02
Kidney - 5 - 0.01
Jaw - 4 - 0.01
Testicles - 4 - 0.01
Face - 3 - 0.01
Mouth - 3 - 0.01
Teeth - 3 - 0.01
Coccyx - 3 - 0.01
Scapula - 2 - 0.00
Buttocks - 2 - 0.00
Spleen - 2 - 0.00
Ear - 1 - 0.00
Totals - 2,280 - 6.32
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