The Role Of A Coach In The Prevention Of An Anterior Cruciate Ligament Injury

George Churchill

SSP211

The Role of a Coach in the Prevention of an Anterior Cruciate Ligament Injury

Introduction Many who witnessed the game between Sweden and England in the 2006 World Cup will remember it not for the 2-2 draw but mostly because of the anterior cruciate ligament injury suffered by Michael Owen. As he received the ball, he passed and turned to run, but his planted foot had got caught in the turf, causing a twisting movement that put stress on the ligaments causing a rupture to the anterior ligament. The focus on this particular injury points to a number of open subjects, such as new technology in modern football boots and conditions of the playing surface playing a big part in today’s present game. The speed and tempo is also much faster and more physical compared with the past and requires the players to twist, turn, jump and move at a far more advanced level then ever before. With injuries to the cruciate ligaments becoming more common there has been constant focus in the media and on television, with replays becoming more analysed, showing that the playing surface and boot the player has worn has contributed. Michael Owen’s case at the 2006 World Cup showed some evidence of this while he sustained anterior ligament damage. The ACL injury is more common in woman, and researchers have found it is three times as likely to happen to a female in football then in a male athlete, this may be due to differences in hormone levels on ligament strength and stiffness, neuromuscular control, lower limb biomechanics, ligament strength and fatigue. Findings have shown a difference in neuromuscular control in women when landing jumps (women appear to have less hip and knee flexion than men). Epidemiology The knee is one of the most frequently injured joints in sportspeople (Bollen, 1998) and injury to the ACL is an important example of a mechanism that may lead to weakening of the knee functions (meniscus, valgus and varus etc). The anterior cruciate ligament (ACL) is the most commonly damaged ligament of the knee and accounts for up to 50% 1

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of documented ligamentous knee injuries (Barker et al, 2007). This lies deep within the knee joint, connecting the thigh bone with the shin bone and its function is to prevent the tibia from sliding out in front of the femur, and provides rotational stability to the knee by preventing excessive rotation movements.

More than 100,000 knee arthroscopies (keyhole repair procedures) and 50,000 knee replacements were carried out in Britain last year, many on otherwise fit and healthy individuals. Among skiers, knee injuries account for 25 per cent of all accidents on the slopes, 1 skier in 2,000 injured an ACL last season. They are also common in those who play tennis, squash, netball and football for fun. Health-mapping information reveals that areas of the country dominated by young families and recent graduates have high hospital admission rates for these types of recreational injuries (Bee, 2006).

Daily activities apply around 454N of stress to the ligament but it is able to tolerate up to 1730N before it ruptures (Dye & Cannon 1988). The ACL is in a position of maximum stress when the knee is at full extension or at 90 degree flexion. They most regurlarly occur when the knee suffers valgus stress (tibia is turned outward in relation to the femur, resulting in a knock-knee’d appearance) with lateral rotation in a foot planted position, as what happened in Owen’s injury. The ACL provides 86% of the resistance to anterior displacement and 30% to the medial displacement (Palastanga, Field & Soames, 1989). Because of the amount of force that is 2

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required to damage the ACL it is not uncommon for other structures within the knee such as the meniscus (cartilage) or medial ligament to also be damaged.

Non-contact

mechanisms (Michael Owen injury) have consistently accounted for more than 80% of anterior cruciate ligament injuries with the majority occurring near end range extension (Rees and Gleeson, 1999). Biomechanics of the Anterior Cruciate Ligament The anterior cruciate ligament (ACL) is one of the most important of four strong ligaments connecting the bones of the knee joint. Ligaments are strong, dense structures made of connective tissue that stabilize a joint. They connect bone to bone across the joint. The function of the ACL is to provide stability to the knee and minimize stress across the knee joint. It restrains excessive forward movement of the lower leg bone (the tibia) in relation to the thigh bone (the femur). It also limits rotational movements of the knee.

Causes of ACL Anterior cruciate ligament injuries occur when a great amount of force is placed upon the knee in a bent position, or when too much muscular force is applied by the individual. The anterior cruciate ligament can support a force of 1700 N before complete failure (Bollen, 1998). When an anterior cruciate ligament ruptures or tears, the patient may hear a pop or feel the knee snap out and back into place. An anterior cruciate ligament injury may occur when the athlete suddenly decelerates and changes directions while running, pivoting, hitting the ground after a jump (heading the ball) or overextending the knee joint while kicking the ball (called hyper extended knee). A blow to the side of the

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knee, which can occur during a football tackle, may also result in an ACL tear.

Diagnosis of an Anterior Cruciate Ligament Injury Proper initial diagnosis and attention are paramount in the acute injury because inadequate treatment often leads to poor healing and chronic instability (Perlman, 1996). During the injury the athlete usually experiences a popping/cracking noise and will know straight away they are unable to continue with the game, with the sense that something bad has happened. Immediately after the injury, the knee will usually swell up really bad and the feeling of instability within the knee will be the major complaint from the athlete. Decreased ability to straighten the knee will become apparent and if there is tenderness at the medial side of the joint then it could be an indication of meniscal damage as well.

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To diagnose the extent of damage the Lachman Test (pulling shin bone forward) and the Pivot Shift Maneuver (usually performed under anesthesia) can be performed with complete knee examinations and a comparison of the uninjured knee to make sure that another injury is not overlooked. MRI scans are also used to evaluate ligament and cartilage damage.

Coaches Role (also see prevention & psychological aspects) When a serious injury occurs to the anterior cruciate ligaments of the knee, the role of the coach becomes more important to an athlete in many ways. But the main focus the coach should have is on how to prevent this injury from happening in the first place, thus preventing harm to the athlete. A coach is responsible for an athlete, and has control over important aspects of there life. These include training techniques, nutrition, sports kit, training facilities, warm ups, cool downs and travelling. All of those just mentioned can assist in causing injury and it is up to the coach, whether or not they are assisted by staff,

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who must take responsibility in making sure the correct environments for peak fitness is maintained and not damaged in any way that could lead to injury. A coach is there to take responsibility for teaching skills, techniques and strategies, the most important of these is the safety aspect and that’s why all coaches must maintain certification in cardiopulmonary Resuscitation (CPR) and Emergency First Aid. Psychological Aspects The coach is very much needed to motivate a player when they suffer an injury. Motivation is the desire that leads an athlete to engage in, or sustain, a particular activity (Magill, 1989). Injury to the knee requires a higher degree of psychological adjustment then it would for a hamstring or groin tear (Gordon, Milios & Grove, 1991). The psychological reaction of any athlete to a sports injury is similar to a grief response, and will often evolve a number of definite stages (Weiss, 1987). Athletes can go through stages of denial, and anger and most commonly depression. The coaches role is to motivate the athlete, make them feel important, make it known they are still part of plans and that they are sorely missed to build esteem within the player to set targets and reach goals. It is up to the coach to instill self belief that the athlete can overcome anything and come back stronger then ever before. Whenever there is a meeting, team building activities or any important future plans the injured athlete must be kept involved as a psychological boost. As with any ACL injury, the athlete needs to regain full confidence in their ability to regain full functional capacity, such as running on uneven surfaces or changing direction suddenly. Throughout rehabilitation the athlete’s confidence should be slowly regained by gradually attempting more difficult agility tasks and setting realistic goals and timeframes (Mattacola & Dwyer, 2002). Prevention The first part of injury prevention is the evaluation of an athlete’s physical condition prior to any activities. It is up to the coach to identify physical conditions predisposing

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(susceptible) the individual to any increased risk of injury through pre-participation screening. This would include producing a baseline assessment form to measure an athlete’s peak performance when at full fitness, so in the case of an athlete injuring there knee, if at full fitness their knee could produce 850N, then that would be their target to achieve in rehabilitation. The aim of an assessment is to identify any problems associated with posture, strength, patterns of movement and flexibility that could contribute to any injuries in the future.

Although anything found in the assessment may not be

symptomatic, the effects of repetitive stress or movements may over a period of time result in a loss of function. The other significant advantage to undergoing a pre screening assessment is that precision of movement and stability is often gained through correcting the deficiencies which may in turn, increase or improve the performance of an athlete.

The coaches role in the prevention is very important, they provide the training sessions everyday to there athletes. What is crucial when organizing and then delivering these sessions is to implement exercises, warm ups and workouts that not only keep the athlete fit but also help in preventing any future injuries. The coach must increase flexibility, increase strength, proprioception (senses of the joints) and also use plyometric exercises to increase speed and muscular contractions. It is recommended a participant should be able to perform 5 repetitions of the squat exercise at 60% before doing any plyometric exercises (Chu, 1998), otherwise it could have an adverse effect (lead to injury) rather then a positive one (help prevent injury).

In the case of Michael Owen’s injury the role of the football boot is very significant. As with any footballer different boots can effect how the athlete runs, kicks, jumps, twists and turns. Owen’s injury was caused by his studs getting caught in the turf as he tried to twist and run after passing the ball. Research has shown that a boot with a higher number of shorter, more broad studs can prevent the foot from becoming fixed to the ground. Boots with longer studs produce significantly higher torsional resistance and are associated with a higher ACL injury rate (Anderson et al, 1997).

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A coach should always check a players kit to make sure its safe and durable for the surface to be played on. In the 1997/98 football premier league season Gordon Strachan, the manager of Coventry City, banned all his squad from wearing Adidas Predator Blades, this was due to some minor injuries that had occurred in training and from players slipping over on wet surfaces. Strachan imposed the ban because he was the coach, the one who had the responsibilty of the players in his hands and he felt it necessary to make his players wear the correct boots.

To prevent knee injuries the coach should focus training on the quadriceps, hamstrings, gastrocnemius, iliotibial tract and adductors because these muscles contribute the most to the stability of the knee. It is also proven that a treadmill set up at an incline slightly greater then 12% reduces ACL strain and patellofemoral strain but recruits greater quadriceps activity, meaning it may be beneficial to ACL rehab programs (Lange et al. 1996).

Classification of Anterior Cruciate Ligament Injuries

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Traditionally, ACL injuries have been classified in clinical practice as Grade I (mild), Grade II (moderate) and Grade III (severe) injuries. An ACL injury is usually called a sprain, this occurs when the fibers of the ligament are either stretched or torn. An ACL avulsion occurs when the ACL is torn away from either the upper leg bone or lower leg bone. This type of injury is more common in children than adults. An avulsion fracture occurs when the ACL is torn away from the leg bone with a piece of the bone (Lehnert, 2004).

The following are classifications of an ACL injury; Grade I sprain •

There is no tear to the anterior ligament

•

The fibers of the ligament are stretched

•

There is some swelling but the knee isn’t unstable Grade II sprain

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The anterior ligament is partially torn

•

The swelling is moderate

•

The knee may feel slightly unstable

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Grade III sprain •

The ligament has torn completely

•

There may be a lot of swelling within 2-24 hours

•

The ligament cannot control the knee giving an unstable feeling

Range of Motion Range of motion must be regained before functional rehabilitation. Regardless of weight bearing capacity, knee extension and flexion should begin as soon as day one after surgery (Norris, C. M. 1998).

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Management Early management includes PRICE (Protection, Rest, Ice, Compression and Elevation). Cryotherapy should be used immediately after the injury (Knight, 1995). Surgery will not take place for two to three weeks. This gives all the swelling in the knee to be resolved that prevents any implications during surgery. Physiotherapists will work with the coach and backroom staff to make decisions on how to prevent any further damage being sustained before the surgery. This usually consists of attaching a knee brace, keeping the knee compressed, complete rest and the use of anti-inflammatory prescriptions. To control swelling new technology such as the knee cryo cuff device can be fitted, this provides cold therapy to the knee with compression of 30 mm Hg when the reservoir cooler is held 50 cm above the cuff. Benefits of Cryotherapy include a decrease in metabolism that limits secondary hypoxic injury (Knight, 1995). While cold therapy is being used, exercises should be initiated to maintain range of motion and assist lymphatic drainage (Mattacola & Dwyer, 2002).

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The inured knee should be elevated 15 to 25cm above the level of the heart to facilitate venous and lymphatic drainage until the swelling has begun to resolve (Knight, 1995). If medicine is required to aid pain relief non-steroidal anti-inflammatory drugs are preferable to narcotics (Mattacola & Dwyer, 2002). In some patients, the use of properly fitted crutches should be considered during the initial, most painful period following injury. Weight-bearing should occur as tolerated by the patient. Gait should be normal and painless and can be advanced as tolerated (Wolfe et al, 2001). The most important stage of the rehabilitation is the first two weeks after surgery. This is when bleeding can occur in the knee joint and it is very important to prevent this from happening. This is where the knee cryo cuff plays its role, by preventing swelling allowing the rehabilitation to be speeded up. By reducing swelling and stopping bleeding from occurring in the knee joint (haemarthrosis) the athlete can gain better range of motion on the knee. In some cases if everything goes to plan full hyperextension of the knee can be achieved on the day after surgery. During the first five days, it is important to have rest, so the athlete will usually stay in bed, still doing range of motion to disperse fluid and prevent stiffness of the knee.. Another piece of technology that can help in these stages is a Continuous Passive Motion Machine, which bends and straightens the knee continually.

After the first week, 100 degree flexion of the knee should be achievable, this can move up to 135 degrees after 4 weeks. To begin strengthening of the knee the athlete will have to wait between one month and three months, depending on progress. This can be aggressive (lifting weights), but only when full motion of the knee can be achieved. Also in this duration proprioception must be regained, to increase stability in the knee. Both tension and mechanoreceptors are present in the ACL. Failure of the feedback system from these structures can result in a loss of reflex muscular splinting and increase the likelihood of re-injury (Kennedy et al, 1982). The nerves damaged in the injury can

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cause signals to the brain to be damaged, so the body wont be able to calculate movements of the knee with body movements, such as jumping and landing.

The coach

and physiotherapist must work together with the player to make sure the player does not suffer any relapses during this period.

After three months the athlete can start 50% walking and 50% light jogging, and around the four month period that can be progressed to ball work, patterned running, and exercises implemented by the physio with the coach contributing some training techniques for balance, agility and strength. It is very important in this period of time that the coach supervises the athlete very closely, making sure they are doing there rehabilitation program properly and reaching there goals and keeping them motivated.

References Anderson, M. K., Hall, S. J., and Martin, M. Foundations of Athletic Training: Prevention, assessment and management. Lippincott, Williams and Wilkins, 2004 Barker et al, (2007) BTEC National Sport: Book 2: Bk. 2. Btec National Bee, P (2006) The Times Article (Online), Available: http://women.timesonline.co.uk/tol/life_and_style/women/body_and_soul/article678066. ece Boyd, P. M., & Bogdan, R.J. (1993) Sports Injuries. In Lorimer, D.L. Neales Common Foot Disorder: Diagnosis and management, a general clinical guide (4th Ed). Churchill Livingstone, Edinburgh.

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Crossman, J (2001) Coping with Sports Injuries: Psychological Strategies for Rehabilitation. Oxford University Press Crichton, K.J., Fricker, P.A., Purdam, C., & Watson, A.S. (1995) Injuries to the pelvis and lower limb. In Bloomfield, J., Fricker, P.A., & Fitch K.D. Science and Medicine in Sport (2nd Ed). Blackwell Science Pty Ltd, Victoria Gleeson, M & Maughan R (2004) The Biochemical Basis of Sports Performance. Oxford University Press Hackney, R., & Wallace, A. (1999) Sports Medicine Handbook. BMJ Publishing Group. London. Houglum, P. (2005) Therapeutic Exercise for Musculoskeletal Injuries. Human Kinetics Knight, K.L. (1995) Initial care of acute injuries: the RICES technique. In Cryotherapy in sport injury management. Human Kinetics. Champaign, Ill. Lynch, S.A., & Renstrom, A.P. (1999) Treatment of acute ligament rupture in the athlete: conservative versus surgical treatment. Sports Medicine McGinnis PM. Biomechanics of sport and Exercise (2005) Human Kinetics Moore, K.L. (1992) Clinically Oriented Anatomy (3rd Ed). Williams & Wilkins. Baltimore. Norris, C. M. (1998) Sports Injuries: Diagnosis and Management for Physiotherapists. Butterworth Heinemann Palastanga, N, Field, D & Soames R (1989) Anatomy and Human Movement. Butterworth-Heinemann

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Perlman, A & Schulze-Delrieu, K (1996) Deglutition and Its Disorders: Anatomy, Physiology, Clinical Diagnosis and Management. Singular Press Woods, B & McIlveen R (1998) Applying Psychology to Sports. Hodder Arnold

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