ACL Prevention Program (PEP Program: Prevent injury and Enhance Performance)

Research

• Several research studies indicate that this injury is more common in female athletes

• Instantaneous loss of motor control while in combination with landing with knees and hips straight as been highlighted to increase incidence of knee and ACL injury.

• The evidence shows that neuromuscular training including plyometrics, balance, and technique training reduces the risk of serious knee injuries in athletes

• All current preventative programs are different but centre on alteration of neuromuscular risk factors; they must focus on the sports specific demands.

• Training may facilitate NM adaptations to increase joint stabilization and muscular preactivation and reactivation patterns which help protect the ACL and knee joint.

• There is good evidence to support the use balance/proprioceptive training in ACL and knee injury prevention.

• There is good evidence to support the use of plyometric training in combination with other training components injury prevention of ACL and knee injury.

• PEP has been shown to alter lower limb kinematics

• Each program has exercises that pertain to all the components needed in order to reduce risk of ACL and knee injuries.

Overview

Female are more likely to have an ACL injury due to neuromuscular imbalances Four neuromuscular imbalances are observed more often in female than male athletes.

The first observed neuromuscular imbalance is the tendency for females to be ligament dominant. Females demonstrate a tendency to allow stress on ligaments prior to muscular activation to absorb ground reaction forces. Typically during single-leg landing, pivoting, or deceleration, as often occurs during ACL injury, the female athlete allows the ground reaction force to control the direction of motion of the lower extremity joints, especially the knee joint. The lack of dynamic muscular control of the joint leads to increased valgus motion, increased force, and high torque at the knee and ACL.

The second imbalance is termed quadriceps dominance. With quadriceps dominance, female athletes activate their knee extensors preferentially over their knee flexors during sports movements to stabilize their knee joint, which accentuates and perpetuates strength and coordination imbalances between these muscles. The third imbalance is leg dominance. Leg dominance is the imbalance between muscular strength and coordination on opposite limbs, with 1 limb often demonstrating greater strength and coordination. Limb dominance may place both the weaker, less-coordinated limb and the stronger limb at increased risk of ACL injury. The weaker limb is compromised in its ability to dissipate forces and torques, while the stronger limb may be subject to high forces and torques due to increased dependence and increased loading on that side in high-force situations.

The fourth imbalance often observed in female athletes is trunk dominance. Trunk dominance is characterized by increased motion of the body’s centre of mass due to the absence of neuromuscular control of approximately two-thirds of the body mass during single-leg landing, pivoting, or deceleration.

Any injury prevention strategy must incorporate corrections to the observed imbalances through post warm up drills ideally these need to be conducted on a daily basis to alter neuromuscular control. The evidence suggests that a phenomenon called central fatigued has been linked to poor control and proprioception. These variables have a relationship to higher incidence of injury.

Further individual functional control issues and imbalances must be addressed in their own strength and conditioning sessions and Strength and conditioning input united with the patterning type work from the Physiotherapy team.

ACL Prevention Program

1. Plyometeric squat jump2. Lateral jumps.3. Nordic Hamstrings4. Single leg dynamic lunge5. X hops6. Single leg bosu balance7. Wall jumps (minimum knee flexion)

Plyometeric squat jump

Correct Landing

Instruction: Stand on ground with feet approximately shoulder width-perform a quick squat

and then explode into a jump- hold the landing for a 2 count Perform 20 times.

Incorrect landing

Things to look for: When landing make sure to land softly on balls of feet keeping knees slightly bent and pointing straight forward.

Lateral jumps

.

Instruction: Stand with feet slightly apart- Push off ground with plant leg while moving in a sideways direction landing on opposite foot- hold 2 seconds- repeat with other leg Perform 10 times each leg.

Things to look for: Explosion at take off with plant leg making sure knee does not fall in to midline of body and on landing make sure knee stays in a forward direction with a slight bend.

Nordic Hamstrings

Instruction: Start on knees with arms crossed resting on chest and your partner holding your feet. Keeping your body straight, slowly lower self towards floor and return to upright position. Repeat 20 times.

Things to look for: Be sure to tighten your stomach while moving forward and back. Make sure not to arch back when returning to start position.

Single leg dynamic lunge

Correct

Instruction: Take large step forward and slowly lower self towards ground keeping your knee directly over your toes. Repeat 10 times each side.

X hops

X hops. The athlete faces a quadrant pattern and stands

on a single limb with the support knee slightly bent. She hopsdiagonally, lands in the opposite quadrant, maintains forwardstance, and holds the deep knee-flexion landing for 3 seconds. Shethen hops laterally into the side quadrant and again holds the landing.Next she hops diagonally backward and holds the jump. Finally,she hops laterally into the initial quadrant and holds the landing.repeats this pattern for 2 x 15 reps. Encourage the athlete to maintain balance during each landing, Keeping her eyes up and the visual focus away from her feet.

Single leg bosu balance

Single-leg balance. The balance drills are performed on a bosuThe athlete begins on the bosu with a 2-legged stance with feet shoulder widthapart, in a single-leg position. Maintain deep knee flexion.

Wall Jumps (Minimum knee flexion)

Wall jumps. The athlete stands erect with the arms semi extended overhead. This vertical jump requires minimal knee flexion.The gastrocnemius muscles should create the vertical height, and the arms should extend fully at the top of the jump. 3 x 15 reps.

References

Petersen W, Braun C, Bock W, et al. 2005; A controlled prospective case control study of a prevention training program in female team handball players: the German experience. Arch Orthop Trauma Surg. 125(9):614-621.

Gilchrist J, Mandelbaum BR, Melancon H, et al. 2008; A randomized controlled trial to prevent noncontact anterior cruciate ligament injury in female collegiate soccer players. Am J Sports Med. 36(8):1476-1483.

Hewett TE, Torg JS, Boden BP. 2009; Video analysis of trunk and knee motion during non-contact anterior cruciate ligament injury in female athletes: lateral trunk and knee abduction motion are combined components of the injury mechanism. Br J Sports Med. 43(6):417-422.

Hewett TE. 2009; Prevention of noncontact ACL injuries in women: use of the core of evidence to clip the wings of a “Black Swan.” Curr Sports Med Rep. 8(5):219-221.

Zazulak BT, Hewett TE, Reeves NP, Goldberg B, Cholewicki J 2007. Deficits in neuromuscular control of the trunk predict knee injury risk: a prospective biomechanical-epidemiologic study. Am J Sports Med.; 35(7):1123-1130.

Chappell JD, Yu B, Kirkendall DT, Garrett WE 2002. A comparison of kneekinetics between male and female recreational athletes in stop-jump tasks.Am J Sports Med.;30:261–267.38.

Hewett TE, Myer GD, Ford KR 2004;. Decrease in neuromuscular control aboutthe knee with maturation in female athletes. J Bone Joint Surg Am. 86:1601–1608.39.

Malinzak RA, Colby SM, Kirkendall DT, Yu B, Garrett WE. 2001 A comparisonof knee joint motion patterns between men and women in selectedathletic tasks. Clin Biomech (Bristol, Avon);16:438–445.

Hewett TE, Lindenfeld TN, Riccobene JV, Noyes FR. 1999 The effect of neuromuscular training on the incidence of knee injury in female athletes. A prospective study. Am J Sports Med. 27(6):699-706.

Hutchinson MR, Ireland ML. 1995; Knee injuries in female athletes. Sports Med. 19(4):288-302.

Ferretti A, Papandrea P, Conteduca F, Mariani PP. 1992; Knee ligament injuries in volleyball players. Am J Sports Med. 20(2):203-207.

Hewett TE, Stroupe AL, Nance TA, Noyes FR. 1996; Plyometric training in female athletes. Decreased impact forces and increased hamstring torques. Am J Sports Med. 24(6):765-773.

Huston LJ, Wojtys EM. 1996; Neuromuscular performance characteristics in elite female athletes. Am J Sports Med. 24(4):427-436.

Gerberich SG, Luhmann S, Finke C, Priest JD, Beard BJ. 1987; Analysis of severe injuries associated with volleyball activities. Phys Sportsmed. 15(8):75-79.

Gray J, Taunton JE, McKenzie DC, Clement DB, McConkey JP, Davidson RG. 1985; A survey of injuries to the anterior cruciate ligament of the knee in female basketball players. Int J Sports Med. 6(6):314-316.

Zelisko JA, Noble HB, Porter M. 1982; A comparison of men’s and women’s professional basketball injuries. Am J Sports Med. 10(5):297-299.

Freedman KB, Glasgow MT, Glasgow SG, Bernstein J. 1998; Anterior cruciate ligament injury and reconstruction among university students. Clin Orthop Relat Res. (356):208-212.

Heidt RS Jr, Sweeterman LM, Carlonas RL, Traub JA, Tekulve FX. 2000; Avoidance of soccer injuries with preseason conditioning. Am J Sports Med. 28(5):659-662.

Mandelbaum 2002. B. ACL prevention strategies in the female athlete and soccer: implementation of a neuromuscular training program to determine its efficacy on the incidence of ACL injury. In: AAOSM 2002 Specialty Day; Dallas, TX;

Söderman K, Werner S, Pietilä T, Engström B, Alfredson H. 2000; Balance board training: prevention of traumatic injuries of the lower extremities in female soccer players? A prospective randomized intervention study. Knee Surg Sports Traumatol Arthrosc. 8(6):356-363.

Myklebust G, Engebretsen L, Braekken IH, Skjølberg A, Olsen OE, Bahr R. 2003; Prevention of anterior cruciate ligament injuries in female team handball players: a prospective intervention study over three seasons. Clin J Sport Med. 13(2):71-78.

Knapik JJ, Bauman CL, Jones BH, et al. 1991; Preseason strength and flexibility imbalances associated with athletic injuries in female collegiate athletes. Am J Sports Med. 19(1):76-81.

Baumhauer JF, Alosa DM, Renström AF, Trevino S, Beynnon B1995;. A prospective study of ankle injury risk factors. Am J Sports Med. 23(5):564-570.

Wedderkopp N, Kaltoft M, Lundgaard B, Rosendahl M, Froberg K1999;. Prevention of injuries in young female players in European team handball. A prospective intervention study. Scand J Med Sci Sports. 9(1):41-47.