Heading injuries out of soccer: A review of the literature

Monash University Accident Research Centre – Report No. 125 - 1997

Authors: A.C. McGrath & J. Ozanne-Smith

Abstract:

Soccer is the most popular sport in the world, and one of the most popular in Australia. Soccer is characterised as vigorous, high intensity, intermittent, ball and contact sport. The characteristics of soccer along with the required functional activities obviously places great demands on the technical and physical skills of individual players. A direct blow from a soccer ball or a stray kick may result in fractures, bruising, or even death. Soccer players can also suffer from a range of overuse injuries associated with running, jumping, pivoting, heading and kicking of the ball. The overall aim of this report is to critically review both the formal literature and informal sources that describe injury prevention measures, or countermeasures, for soccer. The range of countermeasures for preventing soccer injuries is presented in this report, together with an assessment of the extent to which they have been formally demonstrated to be effective. Such countermeasures include pre-season conditioning, protective equipment including shin guards, warm-up programs, attention to environmental conditions, adequate footwear, modified rules, education and coaching, first aid and rehabilitation. Recommendations include the need to conduct more biomechanical and epidemiological research into the mechanisms of injury; further development and testing of protective equipment; improving education for both players and coaches, particularly at the wider community level; adopting modified rules for children; extending pre-participation screening to the general soccer community; providing prompt first aid; and improved injury data collections, particularly for the less formal level of play.

Executive Summary

Soccer is characterised as vigorous, high intensity, intermittent, ball and contact sport. Functional activities include acceleration, deceleration, jumping, cutting, pivoting, turning, heading and kicking of the ball . It is obvious that the game of soccer puts many demands on the technical and physical skills of the individual player . Soccer is one of the most popular sports with over 270,000 registered Australian players and approximately 200 million players in 186 countries registered with the International Federation of Football Association . Further there is estimated to be a equal number of unlicensed soccer players .

With an increase in popularity and expectation of players, along with the characteristics of soccer, significant numbers of injuries are conceivable. Although a significant amount has been published on the epidemiology and biomechanics of soccer injuries, there are few formal, controlled evaluations of the effectiveness of injury prevention countermeasures.

This report aims to critically review both formal literature and informal sources that describe injury prevention measures (countermeasures). It provides an evaluation of the extent to which these countermeasures have been demonstrated to be effective. Unlike other literature describing soccer injuries, this report does not specifically focus on the epidemiology of soccer injuries, nor their aetiology. Instead, it presents a detailed examination of the range of countermeasures promoted to prevent soccer injuries. A brief overview of the epidemiology of soccer injuries, particularly from an Australian perspective, is given to set the scene for the subsequent discussion of countermeasures.

Recommendations for further research, development and implementation are based on the review presented here and discussions with experts acknowledged in this report. Many of the recommended countermeasures have not yet been proven to be effective and further controlled evaluation studies are needed. A summary of the countermeasures reviewed and recommendations for further research, development and implementation are given below.

LOWER LEG INJURIES AND TECHNIQUE

The nature of the game of soccer, in which players make sharp turns off a planted foot, and intense contact with the ball and other players, along with the essential underlying components of running and kicking, indicate the vulnerability of the lower extremities. The epidemiological soccer literature clearly indicates that the majority of soccer injuries occur to the lower extremities. Lower extremity injuries account for between 58% to 93% of all injuries for adults and 39.1% to 89% for children. The dominant injuries occur to the knees, ankles and shins. Countermeasures include correct footwear and shin guards.

Recommendations

Studies are required on the causes and prevention of lower leg injuries. Research questions still to be answered included:
Which features of footwear are protective against soccer injuries?
Where should the balance lie between foot protection and stabilising effects of footwear and flexibility of shoes etc.?
What is the interaction between footwear and specific playing surfaces?
Do cushioning effects of footwear mask longer term damaging effects?
Research studies need to take into account measures of exposure such as hours played, hours of training, position on the field etc.
Evidence on the effects of interventions between footwear and surfaces should be reviewed with reference to other sports.
Where the effectiveness of countermeasures have been proven and regulated eg. shin guards, enforcement at all levels of the game during practice and competition should occur.
Shin guards and footwear should be further and continually developed.
Equipment such as shin guards and footwear should be fitted with professional advice.
The use of wobble board training should be encouraged.

HEAD INJURIES

While the vast majority of soccer injuries occur to the lower extremities, injuries to the head and neck may also occur. From the international literature, the proportion of total injuries to the head, spine and trunk areas ranges from 4-22% in adults and 9-26% in youths. Head injuries are sustained from heading the ball, ball strikes to the head and head to head contact, most often when two players attempt to head the ball simultaneously. Common head injuries include lacerations and concussion. Unlike injuries to the lower extremities, injuries to the head and neck have greater potential to be catastrophic.

Recommendations

Use only plastic coated balls
Once water resistance qualities are lost, replace the ball.
Use the appropriate sized ball for the age and gender group playing.
Teach the player to head correctly and to maintain eye contact with the ball before and after contact is made (Dods, undated).
Ensure the head and neck are kept rigid at impact and, once this basic technique has been acquired, only then progress to the standing jump and finally to the running jump (Dods, undated).
The development of strong neck musculature, to keep the neck rigid at impact (Dods, undated).
Strengthen the hip flexor and abdominal muscles for the ballistic action in the standing header.
Children should be specifically trained and monitored in terms of correct heading technique
Investigations should be made into the advantages and disadvantages of a lightweight helmet for soccer.
Epidemiological research into the incidence of head injuries and associated factors should be undertaken
Current evidence is not conclusive, thus further controlled studies of heading need to be conducted.
The recommendations made by NHMRC should be endorsed.

FACIAL INJURIES

Most sports can give rise to dental, mouth and face damage, though contact sports such as soccer, have been shown to have a relatively higher incidence. There is an absence of FIFA rules for protection from orofacial injury and no mention of such devices in texts for coaches and athletes.

Recommendations

Investigate the advantages and disadvantages of developing a light weight soccer helmet.
Epidemiological research into the incidence and circumstances of eye, dental and face injuries should be undertaken based on participation rates.
Barriers to the use of mouthguards should be determined.
Mouthguards should be used by all players.

GOAL POSTS

Over a 16 year period (1979-1994), the Consumer Product Safety Commission, a United States federal government agency, reported at least 21 deaths and an estimated 120 injuries involving falling soccer goal posts had been treated in US hospital emergency rooms. These statistics do not encompass the numerous injuries that occur and do not receive emergency treatment.

Recommendations

Ensure both portable and permanent goals are securely anchored to the ground.
Ensure portable goals are made of a lightweight material.
Dismantle, remove, tie up or secure to a permanent structure portable goals after use.
Cover goals with protective padding.
Conduct further research into goal post design.
Conduct epidemiological studies looking at the mechanism and types of injuries associated with goal posts.

RULES OF THE GAME

Pushing, holding, barging, tripping, striking or intentional kicking are not allowed in soccer and free-kicks are awarded when rules are broken. If a player commits a serious foul, abuses an official or continues to break the rules, then they can be warned with a yellow card, or sent from the field with the presentation of a red card.

Recommendations

Players need to be educated that foul play is not an acceptable part of the game.
The deterrent effect of the send off rule with limited substitution, should be examined in comparison with the benefits of encouraging injured players to leave the field with unlimited substitution.
Rules need to be enforced.

CROWD CONTROL

A major concern to the reputation and popularity of soccer is the worldwide risk of injury and even death through crowd violence. Although Australia has been less prone to this than other countries, signs of tensions in supporting crowds have begun to emerge in recent years.

Recommendations

Ensure that the FIFA regulations are fully enforced

PHYSICAL PREPARATION

A soccer player needs to meet at least minimum physical, physiological and psychological requirements to cope with the demands of competition and reduce the risk of injury. Individual player factors are often related to soccer injuries and can be prevented through corrections in training and conditioning. Warm-up and stretching is also recommended to increase playing ability, however, its role in injury prevention is controversial.

Recommendations

More research into the role of warm-up, training and conditioning as an injury prevention measure for soccer is needed.
Controlled research studies should be undertaken into the benefits of different types of warming-up, cooling-down and stretching practices.
Information about warm-up, cool-down and stretching techniques should be developed and widely promoted to improve specific knowledge of techniques and effectiveness.
Simple fitness testing should be conducted prior to soccer competition to ensure adequate fitness levels for competition.
Appropriate education and monitoring of players should be conducted regarding nutritional and hydration demands of soccer, particularly as intensity increases with a training programme, and emphasising complex carbohydrate intake
Recreational soccer players should not train excessively. If fitness is the overall goal, soccer drills could be interspersed with other activities.
Soccer players should consider some form of cross-training (eg. bicycling) to improve their fitness levels and remain injury free.
Soccer skills and fitness should be built-up gradually.
Soccer players with potential biomechanical abnormalities (eg. leg length discrepancies) should have these assessed by a professional who can recommend corrective actions.
More research is needed to determine the threshold and optimal levels of the various training factors under which soccer players are likely to remain injury free.
A campaign aimed at increasing soccer players’ awareness of the injury consequences of training errors should be developed and promoted.

PREVENTING OVERUSE INJURIES

Soccer players, like any athletes today, are expected to train harder and longer, and to commence at an earlier age, if they are to succeed at the elite level. It is, therefore, not surprising that there is an increasing number of overuse injuries. An overuse injury results from an accumulation of stresses to the involved tissue - bone, ligaments or tendons. Alternatively, an overuse injury could result from a previous injury for which the body compensates, by increasing the stress on another part of the body, eventually leading to tissue breakdown and overt injury at the vulnerable site.

Recommendations

More research into the aetiology of overuse injuries needs to be undertaken.
Soccer players should be educated about the risk and severity of overuse injuries.
Soccer players with potential biomechanical error (eg. leg length discrepancies) should have these assessed by a professional who can recommend corrective actions.
Coaches and trainers should be educated in the importance of gradual increases in training, particularly pre-season or in the early part of the season.

ENVIRONMENTAL CONDITION

Traditionally soccer is played on a rectangular field, predominantly a grass surface, and less commonly a surface of sand, gravel or artificial turf. During a game a player covers a large percentage of this area and suffers significant impact forces of two to three times body weight. For this reason the surface and the environmental surrounds are important factors to consider when reviewing the nature and incidence of soccer injuries.

Recommendations

Risk management plans to control environmental hazards should be developed, implemented and monitored for facilities.
More research into the role of environmental conditions such as playing surface and weather conditions should be undertaken in a controlled manner.
Soccer should not be played under extremes of weather conditions.
Adequate player hydration should be ensured.
Soccer players should use a broad spectrum sunscreen in high ultra-violet conditions
A wet globe bulb temperature system should be available at all soccer matches which are played under hot and humid conditions to assess heat load.
Risk management plans should incorporate specific regulations regarding the environment.
Further research needs to be conducted on the interaction between footwear and specific playing surfaces.
Evidence on the effects of interventions between footwear and surfaces should be reviewed with reference to other sports.

MODIFIED RULES AND CHILDREN

Significant differences exist between child and adult athletes. Therefore injury prevention strategies for children should be considered separately to those for adults, despite the fact that their injuries may be attributed to many of the factors associated with adult soccer players.

Recommendations

The modified rules version of soccer (Rooball) should be widely implemented
Children should be encouraged to play with smaller sized balls as in Rooball at all times
Children and adolescents should be taught correct techniques and procedures.
The use of shin guards should be enforced.

EDUCATION AND COACHING

Education, as a component of injury prevention should cover a wide range of aspects such as facilities, training and treatment. Guidelines have been produced by the Australian Sports Commission and the Australian Soccer Federation to aid in school education programs, particularly on Rooball and progression to traditional soccer.

Recommendations

All coaches should be accredited and undergo regular re-accreditation.
Coach education schemes should be updated regularly to ensure they provide current information.
Instruction clinics for the wider community should be developed and made widely available.
Education resources for informal soccer need to be developed and disseminated.
Schools should seek advice from the Aussie Sports Program in terms of modified rules, as well as the state organisation for guidance on program development.

FIRST AID AND REHABILITATION

Injuries need to be properly managed to restrict the possibility of further damage. Overall, the treatment goals are pain relief, promotion of healing, decreased inflammation, and a return to functional and sports activities as soon as possible. This procedure may involve, first aid, taping or bracing, referral and general rehabilitation.

Recommendations

Controlled research is needed to determine the effectiveness of taping and bracing of ankle and knee joints in the primary presentation of injury
Taping or bracing should be considered by professionals in the prevention of re-injury of ankle joints
Return to play after injury should only occur after full recovery
Qualified first aid personnel should be available at all sporting events.
Conduct research into the biomechanics of acceleration, deceleration, jumping, cutting, pivoting, turning, heading and kicking of the ball.
Ensure that all players have prompt and adequate first aid treatment.
Further players should undergo controlled rehabilitation before returning to play after an injury.

INDOOR SOCCER/FUTSAL

Indoor soccer, is played by over 100 countries with 12 million players world wide. Futsal is the only official form of indoor soccer approved under the auspices of the FIFA. While the strategy is the same in both indoor and outdoor soccer, the confined indoor area demands quick reflexes, fast thinking, and pin-point passing and leads to an increase in injuries. Indoor soccer injuries are generally similar to those of the outdoor game.

Recommendations

Well designed studies are required to determine the relative risk of injury between indoor and outdoor soccer.
Epidemiological studies in terms of the mechanism of injury and the relation to the games surrounds needs to be conducted.
Risk management plans should be prepared, implemented and monitored based on the apparent risk of futsal.

GENERAL SUMMARY AND CONCLUSIONS

This report has discussed hospital emergency department data, epidemiological data presented in the literature and the full range of injury prevention activities for preventing soccer injuries. The proportion of emergency department presentations reported for both child and adult injury in Victoria was generally within the ranges found in the literature in terms of body region and nature of injury. In addition to specific recommendations, the following more general recommendations have been made:

Improved data collection about the occurrence of soccer injuries and their associated factors needs to be developed and maintained.
Data about injuries and their associated factors in recreational soccer needs to be collected.
Data collections should conform to guidelines for sports injury surveillance being developed and promoted nationally.
Information about preventing soccer injuries should be disseminated widely through soccer broadcasts, soccer equipment points of sale, soccer and general magazines.
Guidelines for minimum safety requirements for soccer events (including the need for mobile phones, telephone contacts, first aid kits, etc) should be developed and widely disseminated.
Future research studies to determine risk factors and to evaluate the effectiveness of countermeasures need to be controlled.
Risk management plans for sporting bodies, clubs and associations should be developed, implemented, enforced and regularly reviewed.

Risk management plans for facilities should be developed and implemented.

This project was funded by Sport and Recreation Victoria