Field hockey is a fast moving field invasive game that involves hard physical work. The heavy demands are intermittent though average energy expenditures as high as 36.5kJ/min~765kg have been recorded (Dur-nin and Passmore, 1967). Good running is essential as is a readiness for explosive action and an ability to recover rapidly. Fast visual reactions while hitting, dribbling and passing the ball are desirable. There is a high requirement to handle the stick skilfully and efficiently, and the coaching and development of these attributes are important factors in injury avoidance.
Kennedy et al (1977) highlighted the incompleteness of incidence data on sporting injuries. The shortage is pronounced when the frequency, site and severity of injuries in field hockey are being considered. Authorities differ as to the degree of risk inherent in the game. At a high level of competition, Judge (1975) cited a low incidence of injury, but this level accounts for a very small proportion of the total hockey played. Blonstein (1974), listing the most dangerous sports as measured by injury rate per player, ranked field hockey fourth after rugby, soccer and gymnastics. Irrespective of the playing standard, injuries are a serious hazard in many sports particularly where the degree of competition is intense, hockey being no exception. Oliver and associates (1977), relating the experience of the Canadian medical team at the 1976 Montreal Olympic Games, claimed that competition was particularly fierce in the field hockey events at this level. They presented evidence of numerous injuries incurred to support this view.
HOCKEY RULES AND SAFETY
The skills and tactics of the game and the rules that govern play are interrelated. Rules prohibit certain manoeuvres and discipline the execution of skills. Hockey is essentially a non-contact sport yet the rule concerned with obstruction is least understood and open to various interpretations. The rule implies that a player shall not obstruct by running between an opponent and the ball, nor place himself or his stick in any way as to be an obstruction to an opponent. This therefore precludes body-charging or contact, or shielding the ball by turning the body around it. It seems, predictably, that hockey injuries caused by body contact are relatively low, being only 3.9 per cent of total injuries in this sport (Crompton and Tubbs, 1977).
Considering that field hockey is a ‘stick and ball’ game, it is not surprising that 77 per cent of total injuries are implemental (Crompton and Tubbs, 1977). Players may be hit by a vigorously swung stick weighing between 0.48kg and 0.65kg (17 and 23 ounces), or struck by a hard ball travelling at high velocity. These implemental injuries occur to any part of the trunk, head, forearm, hand, leg, shin, ankle and foot and result in lacerations requiring sutures, bruising, oedema and inflammation, with accompanying pain and acute or sustained incapacity. Safety features to control the height of the ball and stick lift are incorporated into the rules of the game. These features, however, do not always inhibit the accidental or intentional breach of the rules and conventions.
To eliminate some of the risks, certain rules are applied and conventions observed to reduce dangerous play. A ball rising accidentally into the air from an imperfection of the playing area, is not governed by any rule and players are relieved when it is brought down. This does not imply that a ball in the air is illegal. The scoop, or aerial or overhead pass is frequently used. It is permissible to raise the ball in the air and over the heads of opponents, provided the pass itself is not dangerous to others, or unlikely to lead to dangerous play. Responsibility for interpreting what is dangerous is at the discretion of the umpires.
In a similar category is the act of flicking the ball so that it rises off the ground, as when a shot is taken at the goals or the ball is passed to a colleague. However, an undercutting hit, when a player has his weight on the rear foot and the head of the stick acutely angled under the ball which results in a sharply rising ball trajectory, should be immediately penalised as dangerous play. A sharply lifted ball can strike a player’s face causing damage to teeth, nose or facial bones.
A rule extremely pertinent to the conduct of the game is that referring to ‘sticks’, which limits the fore-and-aft swing of a player’s stick to shoulder height while hitting or tackling for the ball. Differences in interpretation occur due to the varying statures of players, the diverse postures adopted, and misjudg-ments or loss of technique under competition stress.
SITES OF INJURY
Players are exposed to various injuries during running, turning, twisting and stretching, with vulnerability at many body sites. In each injury zone the injuries can include lacerations, haematomata, dislocations, miscellaneous soft tissue injuries and fractures.
Ambeganonker and Dixit (1971) claimed that the most common severe injury in hockey is dislocation of the knee caused by loss of balance when concentrating on dribbling the ball while taking evasive action from opponents. Dislocation of the ankle joint and stress fractures of the tibia and fibula associated with abrupt changes in direction and speed are also experienced. It is suggested that a principal factor in these joint dislocations and fractures is the spinal flexion demand of the game which constitutes an ergonomically unsound posture for fast controlled locomotion. This stooped position may also precipitate back complaints particularly with taller players. Minor injuries can also occur to the foot, ankle, shin, and knee by being struck with a stick or the ball.
Injuries to the facial area may be caused when the ball rises abruptly in the air or a stick is swung in a high arc. Oliver and co-workers (1977) cited an example of a player at the 1976 Olympic Games who received a broken nose and facial lacerations from a stick slashed across his face. This player completed the last game of competition wearing a protective ice hockey mask and helmet. Running into the raised swing of a stick can cause furious expistaxis and fractures of the nose are commonly associated (Ambeganonker and Dixit, 1971).
Essentially there are three types of tackles – face to face, reverse and chase. Many injuries occur when players are close together as when tackling to dispossess the player in possession. In close face to face confrontations, experienced players conventionally keep to their left to avoid a collision and the swing of the opponent’s stick as the tackle to dispossess is made. The common injuries in these situations are cuts, abra- sions and bruises to hands, forearms, knees, shins and ankles. In tackles from the reverse side it is often difficult to avoid body contact. In executing a chase tackle from the rear of a player travelling at speed who is about to strike the ball, great care is needed to avoid the backward swing of his stick. Failure to do so can result in severe stick-inflicted injuries to the nose, face and teeth.
Several set plays within the game heighten the injury risk. These situations include free hit, hit out and corners.
FREE HIT AND HIT OUT
The free hit and the hit out are the most frequent recurring set plays. A free hit is awarded against a player infringing certain rules. A hit out is awarded if the ball is sent out of play by the attacking team over the opponent’s back line or goal line, and no goal is scored, or sent out accidentally by a defender 22.85m (25 yards) or more distant from the goal line. The hit out is taken by a defender opposite the point where it crossed the back line and usually level with the edge of the striking circle. If these hits are taken quickly, some players may be taken by surprise, not facing or watching the ball. In these circumstances there is a risk of being struck by the ball from behind. A slight delay enables the opposing team to form an arc to ring the ball with three or four players, who are permitted to stand 4.57m (5 yards) from it, with defenders filling the gaps .
The hit is usually driven hard and the intention disguised, although with an effective ring the alternatives are few. Often the only solution is to attempt to drive the ball through the ring of players. The speed of the ball, the proximity of players, combined with the frequency of this set piece, make this feature of the game one of exceptional risk.
The award of a corner presents the most dangerous situation in the game. A penalty or short corner is awarded for an infringement in the striking circle by a defender, or if a defender deliberately sends the ball over the back line. Goals can only be scored from within this striking circle. A long corner is given when the ball is unintentionally cleared over the back line by a defender.
The rules governing a penalty corner allow it to be taken from either side of the goal at a point on the back line 9.14m (10 yards) from goal. Six defenders are permitted to station themselves behind or just to the side of the goal, with the other five remaining beyond the half-way line. The attackers stand at the edge of the striking circle in various groups to deceive the defenders . In the long corner, the ball is initially hit towards the circle from near the intersection of the back and side lines.
When the ball is hit or pushed to the waiting forwards, the defenders move quickly across the circle to tackle the forward in possession before he attempts a shot. All players involved in this set piece are under great pressure. The shooter in possession has very little time to strike the ball at goal. The defenders have little time to assess the situation and take appropriate action. The ball is often struck as hard as possible towards the goal and consequently at the oncoming defenders. The velocity of a well-struck ball may be as high as 128kmh_1 (80mph). The remaining attacking players also rush towards the goal to retrieve rebounds or deflected shots. Thus the situation demands that two opposing sets of players, perhaps totalling a dozen, run towards each other in a confined space, and a ball travelling at high velocity is hit at the goal behind them. If the shot is successfully stopped by the goalkeeper, his usual practice is to kick it clear of the circle. The ball again travels through the crowded players, this time from the opposite direction. In these circumstances, various injuries inflicted by the ball, a stick or collision with another player, particularly the goalkeeper, can occur.
INTRINSIC AND EXTRINSIC FACTORS
Apart from match-determined causes of injury, numerous other key factors can be identified. These can be broadly divided into factors intrinsic and extrinsic to the individual player.
It is generally accepted that certain physiological, neuromuscular and psychomotor qualities are necessary for effective participation in sport. Neglect of these detracts from performance and predisposes the participant to injury. In contrast to some sports that have a tradition of training programmes, minimal preparation in field hockey is common even though physical fitness is perhaps the most important factor in the avoidance of exaggerated response to trauma.
Which positional role is at greatest risk is difficult to establish. However, play is most intense in and near the striking circle. The goalkeeper, although normally wearing protective equipment, is called upon to come into deliberate physical contact with the ball and must therefore play a high risk role, as do attackers who rush towards him to retrieve rebounds. Such is the nature of the game that all players are vulnerable most of the time and are involved in most of the high risk situations that arise.
Field hockey can be played into middle age with the performer relying on a high level of skill and experience to avoid or minimise injury. There is an increased risk of attrition injuries particularly when running and dribbling the ball. The quality and amount of coaching, with emphasis on skilful stickwork, ball control, positional play, recognition of the spirit of the game, can all make a significant contribution to injury avoidance. Injuries due to imperfect skill development are more likely to occur with school and novice hockey players.
Psychological factors rendering an individual susceptible to injury are well recognised (Sanderson, 1977). Under this multifactorial influence, consideration is accorded to the interplay of personality and motivation. An important influence on the incidence of injury is an individual’s commitment to competition and his willingness to take risks. The urge to win or to keep one’s team place is no less in hockey than in other sports where rewards are considerable.
CHARACTERISTICS OF OPPONENTS Unlike combat or some contact sports, little can be done to influence or match the size, strength, speed, skill or aggressiveness of advantaged opponents. However, players should not needlessly be exposed to positional roles or levels of competition beyond their capabilities.
The type and condition of the playing surface can have a significant influence on injury. A player falling on some types of all-weather playing surfaces can receive severe skin abrasions. A hard surface with a worn grass cover often makes the ball ricochet and difficult to control. In heavy muddy conditions, the ball often travels short and as a result play becomes scrappy with sticks being lifted and the ball slashed as players make several attempts to move it. It is also more difficult to maintain balance on such grounds. In inclement weather, any reduction in visibility is hazardous. Rain that reduces vision also makes the ball greasy and the sticks slippery, thus hitting, stopping and stick manipulation become more difficult. Glare caused by brilliant sunshine, or failing daylight, may cause players to momentarily lose sight of the ball in critical situations.
Reduction of risk can be achieved by the amount and quality of equipment used. With the exception of goalkeepers, hockey players arc not disposed to wearing adequate protective clothing.
Various protective items are available to reduce the incidence of injury. Observation alone confirms the need for such equipment to be more widely used in field hockey, as apart from goalkeepers few hockey players take effective protective measures. It is remarkable how little protective equipment is subject to minimum standards of safety. Field testing without controls has been the principal means of justifying the equipment for both the manufacturer and the public. It is recommended that any protective equipment purchased should be of the highest quality available.
Protective equipment for goalkeepers consists of kickers, leg guards, abdominal guard, chest guards, gloves and face mask .
There are two types of kickers, one made of leather with half-sole and a reinforced toe cover that fits over the footwear and is secured by straps. The other is made of padded canvas that straps over the instep of the goalkeeper’s boots. The leather type is heavier and the half-sole tends to impede the mobility and speed of the goalkeeper. The canvas instep type requires extra measures to prevent them coming loose during play but provides a satisfactory standard of protection if used with boots having reinforced toe caps.
Suitable leg guards or pads are similar to those used by wicketkeepers in cricket. Foam rubber strips worn under the pads help to prevent hard shots rebounding from them, as goalkeeping skill involves absorbing the impact and clearing the ball as it falls.
Use of abdominal and chest guards made of padded canvas and inlaid with strips of bamboo cane is advisable. These guards provide effective protection to the torso and can act as a confidence booster. Unlike lacrosse, they are not nearly as widely used by hockey goalkeepers as they should be. Although not as satisfactory, a fencing instructor’s plastron affords some security to the upper torso.
There are various kinds of goalkeeping gloves available with options of padded backs and palms for left and right hands depending on stick carriage. Indoor hockey, where rapid play and artificial lighting often puts goalkeepers at exceptional risk, has promoted the use of goalkeeping face masks. Their employment has spread from the indoor to the outdoor game. Ironically the greatest disadvantage of these masks is that they reduce peripheral vision and interfere with sighting the ball.
Hockey players in outfield roles are advised to wear shin pads, similar to those worn by soccer players, which can be slipped behind stockings. Other shin pads, designed for women and affording some ankle protection, are worn outside the stockings and secured by straps. They are not popular as they interfere with running.
Male players should consider wearing a good quality genital protector or box that can be slipped into the pocket on some athletic supporters. Female players are similarly inadequately protected. Some women games players wear protective brassieres and briefs with padded abdominal and hip sections. All players should consider wearing knee pads, especially on hard playing surfaces. Use of suitable mouth guards should be encouraged to prevent dental injuries. Silk and chamois leather inner gloves used by military aircrews offer some defence against minor abrasions to hands and wrists.
The design and effects of footwear used must be of concern. High ankled canvas hockey boots providing some support are commercially available but worn by a minority. Most players wear low-cut lightweight soccer boots or training shoes, yet these designs and certain type of cleats and studs are implicated in the incidence of ankle and knee injuries. The specific footwear requirements of hockey players have, as yet, been incompletely established.
Injuries seem most pronounced at extreme levels of playing proficiency. The intensity of top competition may promote perilous play while imperfect skill development places novices periodically at risk. Common sites of severe injury are the lower limbs and face but the whole body is vulnerable. The ball and stick constitute potential causes of trauma. Besides the hazards specific to this sport, players are susceptible to many of the injuries common to field invasive games from running, turning, side-stepping, accelerating and decelerating manoeuvres.
Field hockey can be a pleasurable recreation and a challenging and demanding sport. Reduction in the incidence of injury can be achieved if the rules are adhered to, sensible precautions taken and protective equipment utilised. A commitment to personal preparation is also likely to prove fruitful in avoiding injury and enhancing enjoyment.
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