Injuries in football – science researches

Several studies have investigated the incidence of injuries in the football leagues of Europe. An analysis was conducted during the Norway Cup, an annual international youth tournament in which 1459 teams with 25000 players participated in 2987 matches. Fifty-six percent of the 1534 consultations by the medical staff were for injuries sustained during tournament play. 32% percent were the result of accidents while 12% involved illnesses. Of the injuries, 25% were contusions while 20% were sprains and strains. Fractures accounted for 3.5% of injuries. Two thirds of the injuries occurred in the lower extremity with contusions dominating the picture. Sixteen percent of all injuries involved the ankle. The injury rate was found to be 14x1000 match h^-1 in the boys and 32x1000 match h^-1 in the girls. Nine of 10 injured athletes were allowed to play the next day.

A similar study was undertaken during two Danish international youth tournaments in 1984. The 6600 participants, aged 9-19 years, played 945 matches in 5 days. Of the 392 medical consultations, 346(88%) were due to injuries sustained during the tournament. Of the remaining 12% of consultations, 54% were the result of accidents and 46% of them resulted from illness. Injuries to the lower extremity accounted for 80% of the injuries in this report. Contusions were reported in 33% of cases while blisters and abrasions accounted for 20%. Thirteen percent of injuries involved the foot and ankle. Boys were injuried at a rate of 16.1x match ^h-1 while the rate for girls was 29.2x match ^h-1. The oldest girls had the highest incidence overall at 47.2x match h^-1 while the young girls had the lowest. The oldest boys had an incidence 20,6x match h^-1. The relative frequency of injury was thought to be 5% in these large young tournaments. Only 3.7% of these injuries were considered severe.

Two prospective studies were done in Denmark. The first registered injuries for a 1-year period involving 496 boys. These players recorded 312 injuries. Injury incidence increased with the age of players. Seventy percent of the injuries occurred in the lower extremities, with 10% involving the upper extremities. 14% had back pain, 4% of the injuries were fractures with two-thirds involving the upper extremity. The mean incidence of injury for the year was 3,7x 1000 ^h-1 of football. The older boys(16-17 years) had an incidence rate of  4x1000 ^h-1. No differences were found between injury rates in autumn and spring seasons.

The second group was 123 male players in a Danish football club. There were 93 adult males(over 18 years) and 30 boys(16-18 years). An injury was defined as an incident occurring in a game or practice that resulted in missing at least one game or practice season. Eightly-nine players sustained 109 injuries; 43 occurred during practice and 66 occurred during games. 48% percent of the injuries were the most common(36%) and were found equally at all levels. There were 20 knee injuries.

Overuse injuries comprised 37% of all injuries. Ankle injuries and strains had the highest rate of re-injury. Players in the youth and recreational leagues were most frequently injured during tackling(48 and 44%) while 54% of the competitive league injuries occurred during running. 38% of the injuries required treatment at a hospital. 50% of the injuries required treatment at a hospital. 50% of the injuries were treated by players themselves. 35% of the injuries caused an absence for more than 1 month. 28% of the injured players still had complaints at 1 year of follow-up. The injury incidence during games was highest with the competititive players while injury during practice was more prevalent with the recreational players. The youth players had a high incidence of injury in this study.

A questionnaire survey, performed in a Danish emergency room on all football injuries seen over a 1-year period, evaluated 715 injuries in 646 males and 69 females. 86% of the players were injured during matches while 9% involved insufficient warm-up and 5% occurred during training. The most common mechanism of injury was contact with another player. Earlier injuries influenced the current episode in 6% of cases. 46% of the injuries were considered moderate and 44% were classified as minor in severity. 49%  percent of the injuries involved the joints while 30% were abrasions and lacerations. Ankle sprains were the most common injury. Fractures accounted for 18% of the injuries with an equal distribution between upper and lower extremities. 20% needed further care in the out-patient clinic and 7% were hospitalized. The yearly incidence of injury was 5.5% in players less than 18 years old, 17% in players aged 18-25, and 18% in players over 25 years. The severity of the injuries was also found to be less in the younger players.

A French study undertook the analysis of insurance claims submitted as a result of football injuries. The number of accidents recorded was 6153 for 123,175 registered amateur players who played approximately 70,000 matches, 70,000 practice games, and participated in approximately 150,000 training sessions. Risk of injury was increased in the higher level skills. Females and males over 35 had the same injury rate as the juniors. Joint injuries were the most frequent with the ankle involved 20.3% and the knee 13.8% of the time. Fractures accounted for 16.6%(5.4% upper extremity and 6.2% lower extremity). Fractures were the most common injury in players less than 14 years. Sprains accounted for over half of the injuries reported in females.

An emergency room study conducted in Saudi Arabia evaluated 848 sports-related( 8.4% of emergency visits); 542(64%) were the result of football play. Soft-tissue injuries numbered 358(66%). Contusions and lacerations numbered 125(23%). Ruptured tendons occurred in 11(2% patients). Sprains were found in 141(26%) patients with half involving the ankle. Strains accounted for 40 injuries(7.5%), chiefly involving the gastrocnemius and quadriceps. Ligamentous disruptions were noted in 32(6%), mostly in the ankle and knee. There were 184 bone and joint injuries(34%). Subluxations and dislocations of the digits were seen in 16(3%). Eleven patients had dislocations of shoulders or elbow. Fractures numbered 157(29%). Of all the injuries, 21% were considered severe with 44% classified as moderate. The lower extremity was involved in 320(59%) of the injuries.

A Swedish study followed a senior male football division prospectively for 1 year. The 180 players were examined prior to the season. In 124 players, 256 injuries were sustained during a year. The yearly incidence of injury per player was 0.88 for a minor, 0.38 for moderate and 0.16 for minor injury. 88% of the injuries were localized to the lower extremity. Of these, 177(69%) were the result of trauma and 79(31%) were due to overuse. Sprains accounted for 29% of all injuries with 59% involving the ankle and 34% occurring in the knee. Strains accounted for 45 injuries(18%), 80% of which were localized to the lower extremity. 51 knee injuries were seen. 35(69%) were caused by trauma and 16(31%) through overuse. 44 ankle injuries(17%) occurred with 43 sprains and one lateral malleolar fracture. The lateral ligamentous complex was injured in 39(91%) of the 43 cases. 17(47%) of the ankles had been previously sprained. Two thirds of the traumatic injuries occurred in games, 59% of which occurred during contact with another player. 79(31%) injuries were over-use, of which 84% occurred during practice.

Football is becoming increasingly popular on the North American continent. A study of youth football in the USA included 4018 players(age 8-18 years). Injuries reported numbered 176. The overall injury rate was 4.38% with the under-19 age group having the highest incidence at 8.74%. Injury rates lessened as age decreased. Competitive teams had higher injury rates than recreational teams. The most common injury was a sprain(26.7%) with contusions comprising 25%. The ankle was most commonly injured joint, followed by the knee.

A telephone study in the USA contacted the coaches of 80 teams on a weekly basis to request injury information. There were 931 boys and 341 girls ranging in age from 7 to 18 years, with one-half being under the age of 10 years. 29 players sustained 34 injuries, five of which were reccurences. Sixteen boys had 19 injuries while 13 girls incurred 15 injuries. Each player amassed approximately 40h of participation, yielding and injury rate of 0,51x1000^h-1 for boys and 1,1x1000^h-1 for the girls. 17 injuries prevented participation for more than 7 days. The injury rate was 7,7x100^h-1 in the older age groups compared to 0,8x100^h-1 in the younger age groups. Contusions were the most common injury with 13 episodes followed closely by 12 sprains. The upper extremity was involved in six injuries, the head and neck on five occasions and the trunk in one. The lower extremity accounted for 22 injuries.

A review of insurance claims related to football was performed through the largest insurer of secondary school students in the western USA. There were 436 claims among 10,634 players. Minor injuries such as contusions and sprains accounted for 76% of the injuries but involved only 49% of the total cost. The lower extremity involved 58% of the injuries and costs. An ankle sprain was the most common injury site(19%). Knee injuries comprised 11.7% of the total and 28% of the costs. Contusions occurred in 30.7% of the injuries and sprains and strains accounted for 38.1%. The incidence of fracture was 18.8%.

Another report from the USA compared injuries in youth outdoor to youth indoor football. Responses were obtained on 455 players(62.9%) in the outdoor league. The indoor league had a response rate of 60.6%(366 players). 40 players sustained 46 injuries in the outdoor league while 63 players incurred 74 injuries during the indoor league. The majority of the injuries were minor – only two outdoor and six indoor injuries caused an absence of more than 7 days. During game play, the incidence rate of injury per 100h was 4.5 times higher in the indoor league as compared to the outdoor league. Injury rates were lowest in the younger age groups. Physical contact between two players resulted in 66.6% of the injuries(60.9%) in the outdoor league and 70.3% indoor.

Medical assistance was required in 6.5% of the injuries among respondents in the outdoor league while 24.3% of injuries sustained during indoor play needed medical services. 

“Handbook of Sports Medicine and Science - Football(Soccer)”, Björn Eklbom