ACL INJURIES Introduction. ACL Injuries in the Female Athlete Are they preventable? Kevin E. Wilk, PT, DPT, FAPTA

Transcription

1 ACL Injuries in the Female Athlete Are they preventable? Kevin E. Wilk, PT, DPT, FAPTA ACL INJURIES Introduction ACL injuries common in sports & strenuous work So frequent that the seriousness is often forgotten Totally disrupted more than any other knee ligament 200,000 ACL injuries annually USA Fu: AJSM , ,000 ACL surgeries USA Harner: Arthroscopy 04 Noyes & Barber: Arthroscopy 14 Rehab has changed in the past 10 yrs Science to Rehabilitation Knee Homeostasis

2 ACL INJURIES Introduction 1 in 3,500 people will sustain an ACL injury Baer, Harner: Clin Spts Med 07 Estimated 1 million ACL injuries worldwide Females are 4-6 times higher risk of ACL injury ACL outcomes (IKDC scores) of 100 Biau et al: CORR % of ACL patients exhibit radiographic knee OA 7-12 yrs following surgery Pinczewski et al: AJSM 07 Liden et al: Arthroscopy 08 10x greater rate OA in ACL injured knee Fleming et al: JOSPT 03 ACL Injuries Introduction Over 200,000 ACL injuries annually 62-66% sports related, usually non-contact 70% Over 60% in males 67% occurs in individuals yrs of age 26% occurs in yrs 7% occurs in individuals above 45 yrs of age ACL Injuries Introduction National High School Sports Related Injury Surveillance System Swenson et al: MSSE sports 5116 Injuries/17, AE Knee 15% 2.98/10,000 AE MCL injuries: 36% Patellofemoral Joint: 29.5% ACL injuries: 25% Meniscus: 23% ACL Injuries Introduction National High School Sports Related Injury Surveillance System Swenson et al: MSSE 13 Highest Rates (Sports): Football: 6.26/10,000 AE Girls Soccer: 4.23/10,000 AE Girls Gymnastics: 4.23/10,000 AE Girls more injuries in comparable sports Girls at higher risk of ACL injuries Surgery (21% of all knee injur) Girls more ACL Injuries Introduction ACL Age Distribution Scandinavian Registry Lind: Acta Orthop 09 Female peak age 15 yrs Male peak age 20 yrs Risk of Contralateral ACL Injury Systematic review of 13 prospective studies Contralateral Risk > than First Time Risk Sward et al: KSST 10 Q

3 ACL Injuries Introduction Time it takes to rupture an ACL Landing from a jump 40 millisecond from initial ground contact Koga et al: AJSM 10 Mangine: Orthop 92 FEMALE ATHLETES Introduction Females suffer ACL injuries at a higher rate» 4-6 times greater incidence Hutchinson: Spts Med 95 Malone: J So Orthop Assoc ,00 ACL Injuries annually Serious Knee injuries 2-3x as common at high school level Female to male ratio in all high school sports 4.6:1 Chandy,Grana: Phys Spt 85 ACL INJURIES FEMALE ATHLETE Introduction The female athlete between the ages of yrs most susceptible Power, strength & coordination have all been shown to increase with puberty in males but not in females Beunen et al: Exerc Sport Sci 88 Pubertal growth spurts appear to coincide with ACL injury times Ford et al:ajsm 10 FEMALES Introduction Female athletes appear more susceptible than male athletes High school athletes (Chandy) 4.6:1 Soccer players (Lindenfield) 6: 1 Basketball players (Malone) 8:1 Volleyball players (Ferretti) 4:1 Military training (USNA) 10:1 Professional skiiers (Viola) 1.4 : 1 FEMALES Introduction Female athletes appear more susceptible than male athletes Football highest rate ACL injuries but soccer is catching up (newest data) Women injure ACL more than males Women have more non-contact ACL injuries Injury risk for women increase at age yrs of age ACL Injuries in Female Athletes Risk Factors What affects injury rates??? Specific Risk Factors:

4 ACL Injuries in Female Athletes Risk Factors What affects injury rates??? Specific Risk Factors: Increased Knee Abduction angles - valgus Decreased Knee flexion angles Q dominant Increased generalized laxity Decreased H/Q ratios Neuromuscular control deficits Smaller intercondylar notch Running, cutting & landing from jumps Lateral trunk displacement Poor hip strength & control Hormonal changes ACL Injuries in Female Athletes Risk Factors What affects injury rates??? Specific Risk Factors: Increased Knee Abduction angles - valgus Decreased Knee flexion angles Q dominant Increased generalized laxity Decreased H/Q ratios Neuromuscular control deficits Smaller intercondylar notch Running, cutting & landing from jumps Lateral trunk displacement Poor hip strength & control Hormonal changes J Spts Health 12 ACL Injuries in Females Training & Rehab Focus Areas Hip control prevent valgus collapse Hip abduction, ER, extension strength Neuromuscular control & proprioception Knowing where knee/body is in space Trunk control & core strength Preventing lateral displacement H/Q ratio & balance Eliminate quadriceps dominant knee Proper running, cutting, landing mechanics Flexed knee & hip balance position ACL Injuries & Neuromuscular Control Deficits DiStasis et al: JOSPT 13 Gokeler et al: Sports Med 13 Paterno et al: Gait Posture 13 Hewett: J Athl Train 12 Myer et al: AJSM 13 (age & NM control) Hewett et al: AJSM 13 Myer: AJSM 12 Sugimoto et al: Br J Sports Med 12 IMPLICATIONS FOR REHABILITATION JAT 99

5 AJSM 13 AJSM 12 BrJSM 12 ACL Prevention Program How Effective Are They? Arthroscopy 14 FEMALE ATHLETES Introduction Increased numbers of females participating in sports In 2012, over 2.5 million females played organized sports Incidence of knee injury: 1 in 100 ACL injury rates;» Approx 2,200 annually».2/1000 athletic exposures

6 sportmetrics Grindstaff, Hammill, et al: JAT 06 sportmetrics Neuromuscular control training programs & non-contact ACL injury rates in female athletes: A numbers-needed-to treat analysis 5 studies met the inclusion criteria: Hewett et al: AJSM 99 Hewett et al: AJSM 99 Myklebust et al: Scand J MedSci Sports 98 Petersen et al: Arch Orthop Trauma Surg 05 Olsen et al: BMJ 05 Grindstaff, Hammill, et al: JAT 06

7 Introduction What is the cause of the increase rate of injuries? ACL Injuries in Female Athletes Risk Factors What affects injury rates??? Specific Risk Factors: Increased Knee Abduction angles - valgus Decreased Knee flexion angles Q dominant Increased generalized laxity Decreased H/Q ratios Neuromuscular control deficits Smaller intercondylar notch Running, cutting & landing from jumps Lateral trunk displacement Poor hip strength & control Hormonal changes Gender Differences - Anatomic Wider pelvis Increased genu valgum Increased tibial torsion Narrower femoral notch Increased laxity & hip flexibility Less developed thigh musculature

8 Intercondyler notch size Smaller notch greater risk for ACL injury» Anderson: AJSM 87» Souryal : AJSM 88 Notch width indexes less in females» Souryal & Freeman: AJSM 93 No differences between genders» LaPrade AJSM 94 ACL Injuries Femoral Notch & ACL Geometry Ireland: KSST 01 Whitney et al: AJSM 6/2014 Morphometric characteristics of the ACL and femoral intercondylar notch MRI case control pairs (61 females, 27 males) Risk factors for non-contact ACL injury: Decreased ACL volume Decreased femoral notch width Increased bony ridge anteromedial outlet of notch Anatomic Posterior Tibial Slope Greater slope angles result in higher non-contact ACL injury rate Appears to be significant in females compared to males Todd et al: AJSM 10 Incr PTS results in an incr anterior tibial translation DeJour et al: JBJS (B): 94 No agreement on what TS angle puts at greatest risk Wordeman AJSM 12

9 ACL INJURIES IN Dynamic Joint Stability Dependent on muscular co-activation neuromuscular control Knee joint dynamic stabilizers Hamstring / quadriceps Unilateral muscle ratio Historical ratio: 66%??? Appears to be critical element to dynamic stabilization of knee ACL INJURIES IN Dynamic Stabilization Hamstrings to quadriceps ratio < 75% and bilateral hamstring difference of more than 15% Correlated to higher incidence of ACL injuries in female athletes Knapik et al: AJSM 1991 ACL INJURIES IN Gender Differences - Dynamic Stabilization Muscular balance, unilateral H : Q ratios Females have lower H : Q ratios Hewitt, AJSM 1996 Females H : Q ratios 47% Males H : Q ratio 67% ACL INJURIES IN Gender Differences - Dynamic Stabilization Muscular balance, unilateral H : Q ratios High school athletes» H/Q ratio Females 46% Males 68% Females HPT/BW 32% Wilk: Unpub 98, 00 Huston & Wojtys, AJSM 1996 Experimental group (n=100)» 40 female athletes 10 basketball 10 field hockey 8 gymnastics 12 volleyball» 60 male athletes (football) Average age: 19.7 years Huston & Wojtys, AJSM 1996 Control groups (n=40)» 26 males» 14 females Average age: 23.5 years

10 Huston & Wojtys, AJSM 1996 Athletes knees tighter than control group Women s knees looser than men s Women were weaker ( even relative to BW) Women were more dependant on quadriceps Women s hamstrings were not as good a stabilizer as men s hamstrings MUSCLE RECRUITMENT ORDER Spinal Cortical Female athlete G-H-Q Q-H-G* Male athlete G-H-Q H-Q-G Female controls G-H-Q H-Q-G Male controls G-H-Q H-Q-G Dynamic Stabilization Females rely more on their quadriceps to stabilize their knee joints Huston:AJSM 96 Malinzak:Clin Biomech 01 Shultz:J Athl trn 01 Dynamic Stabilization Quadriceps-dominated knee Gender Differences - Laxity Females have greater flexibility greater laxity Females exhibit greater genu recurvatum Females exhibit greater genu valgum Females exhibit greater hip rotation Simoneau:JOSPT 98 ACL Injuries Risk Factor- Knee Laxity Increased knee laxity in an otherwise normal knee is associated with increased risk of ACL injury Myer et al: AJSM 08 Kramer et al: J Sports Med Phys Fitness 07 Increased subtalar joint pronation & navicular drop = increased risk factor for ACL injury Loudon: JOSPT 96

11 Gender Differences - Muscular Performance Females require 100% longer rise time in developing isometric force Komi, Acta Physiol Scand 1978 Females have longer EM delay (from electrical activity movement) Winter, J Appl Physiol, 1991 Gender Differences - Muscular Performance Short electromechanical delay in males compared to females (stiffer muscles) Bell, Med Sci Sports 1986 Female athlete require significantly more time to produce the same force levels, even body weight correction Hakkinnen, J Sports Med Phys Fit 1991 Gender Differences - Muscular Performance Females exhibit lower muscular endurance compared to males Huston,Wojtys:AJSM 96 May increase injury risk Gabbett:Br J Sports Med 02 Rozzi: AJSM 99 Endurance Endurance may play a key role in injury & injury prevention Quality of movement changes Chappell et al: AJSM 06 Wilk et al: J Athl Trn 96 Wilk et al: JOSPT 93 Chappell, Herman, Kirkendall, Garrett: AJSM 06 Fatigue is a risk factor for musculoskeletal injury LE muscle fatigue alters knee kinematics & kinetics during landing from a stop jump 20 athletes (10 male & 10 female) 3-D motion analysis-force plate data Both males & females exhibited a difference Increase in peak tibial anterior shear force, increase in valgus moment, & decreased knee flexion after fatigued Valgus Collapse Valgus force on knee joint during running, cutting or landing from jump Athletes with greater generalized laxity demonstrated increased midfoot loading & medial collapse (112 soccer players) Foss, Ford, Myer, et al: J Athl Trn 09 Valgus Collapse Hewett: Br J Spt Med 09

12 THE FEMALES Prevention Laxity & ACL injuries Correlation between laxity & ACL injury rate A positive measure of knee hyperextension increased odds of ACL injury 5x Myer et al: AJSM 08 THE FEMALE Laxity & ACL injuries Females have greater laxity than males Contracted KT values:» Contracted H/Q muscles» Females decrease 273%» Males decrease by 475% Wojtys: JBJS 02 Proprioception & NM Control Dynamic joint stability is dependent on neuromuscular response time Females with intact knee had superior postural balance over males Following ACL injury, females have poorer proprioception than males Return to normal balance: slower in females compare to males Both males & females: bilateral differences following injury Hewett, et al AOSSM 1999 Athletic Differences Gender differences Biomechanical & EMG analysis Running & cutting Cutting at 45 deg and 90 deg Differences between males & females (biomech & EMG data) Wilk, et al (unpub) :ASMI 1999

13 Chappell, Creighton, Garrett: AJSM 07 Kinematics & EMG of vertical stop jump 36 recreational athletes ( 17 males & 19 females) Significant differences between males & females Females generated decreased knee flexion, hip flexion, increase knee IR & increase in quadriceps activation compared to males Females exhibited increased hamstrings prior to landing but after landing Chappell, Kirkendall, Garrett: AJSM 02 Compared 10 males & 10 female recreational athletes performing forward, vertical and backward stop jump 3 D motion analysis All subjects greater anterior tibial shear with landing from backward stop jump Females greater knee extension & valgus moments with all 3 movements Females exhibited different motor control strategies than males Gender Differences Athletic Performance Jumping and landing Males exhibit greater knee flexion (take-off) Males exhibit 3x greater knee flexor than females on landing Females exhibit less ABD / ADD moments Hewitt, AJSM 96 Huston, et al: Am J Knee Surg 01 Gender differences in knee angle when landing from a jump Studied 24 subjects (12 women) Jumped 20, 40 % 60 cm (motion analysis) Women landed with less knee flexion, & increased loads onto knee joint ACL Rehabilitation Landing from a Jump Females who undergone ACLR demonstrated increased VGRF, & loading rate on uninvolved limb approx 20-28% less During the jump ACLR side exhibited less ability to generate load during takeoffapprox 10-12% less Paterno et al: Clin J Spts Med 07 Gender Differences TRUNK & CORE Video analysis compared males to females during during landing Females landed with greater lateral trunk motion & knee abduction than males Hewett, Torg, Boden: Br J Spts Med 09 Greater trunk displacement Zazulak: AJSM 07

14 Myer, Chu, Brent et a: Clin Spts Med 08 Trunk & hip control exercises & drills to prevent knee injuries Family Predisposition AJSM 09 The Menstrual Cycle Does it affect injury rates??? Gender Differences - Laxity Wojtys & Huston AJSM 98 Female knees are more lax than male Athletic knees tighter than control Laxity changes during menstrual cycle Increased tibial translation (150%)

15 Wojtys, Huston, Boynton, Spindler, Lindenfeld :AJSM 02 Estrogen effect on collagen metabolism and NM performance during menstrual cycle Stages of menstrual cycle and ACL injury More injuries than expected during ovulatory stage (days 10-14) Significantly fewer during follicular stage(1-9) THE MENSTRUAL CYCLE Follicular phase (days 1-9, estrogen and progesterone low Ovulation phase (days 10-14), mid-cycle surge of estrogen & increase in relaxin Luteal phase (days 15-end), progesterone rise, relaxin increase mid-way Gender Differences Hormonal Differences Effects of Hormonal involvement on increased injury risk not conclusive Hewett et al: AJSM 09 Zazulck et al: Sports Med 06 Effects on collagen, laxity, tensile properties Oral contraceptive lower levels of collagen & lower collagen synthesis Miller et al: Am J Physiol Endocrinol Metab 06 ACL INJURIES IN Summary - Significant Differences Female knees are looser Looser knees even after muscle activation (i.e. active KT) Muscle recruitment (slower) Unilateral muscle ratios (H/Q) Athletic performance running & cutting NM control & activation ACL injuries in women appear to be multi-factorial ACL INJURIES IN Summary Greater rate of injuries in females Numerous factors contributing Females unique NM features» H / Q ratios» Muscular activation» Running,cutting,jumping» Athletic performance Prevention is the key

16 ACL Prevention Programs Overview Hewett et al: Am J Sports Med 1999 Soderman et al: Knee Surg Sports Traumatol Arthrosc 2000 Heidt et al: Am J Sports Med 2000 Myklebust et al: Clin J Sports Med 2003 Mandlebaum et al: Am J Sports Med 2005 Olsen et al: BMJ 2005 Petersen et al: Arch Orthop Trauma Surg 2005 Pfeiffer et al: JBJS 2006 Steffen et al: Scand J Med Sci Sports 2008 Gilchrist et al: Am J Sports Med 2008 Kiani et al: Arch Intern Med 2010 LaBella et al: Arch Pediatr Adolesc Med 2011 ACL Prevention Program How Effective Are They? Arthroscopy 14 Labella et al: Arch Ped Adolsec Med 11 ACL Injuries in Females Training & Rehab Focus Areas Hip control prevent valgus collapse Hip abduction, ER, extension strength Neuromuscular control & proprioception Knowing where knee/body is in space Trunk control & core strength Preventing lateral displacement H/Q ratio & balance Eliminate quadriceps dominant knee Proper running, cutting, landing mechanics Flexed knee & hip balance position

17 Stabilization From ABOVE & BELOW

18 RDLs My Favorite Hip Exercises Sidelying clams with manual resistance Seated theraband ER RDLs Single leg front step downs Star drill Instant Replay Single leg bosu ball catches Planks with hip abduction & ext Perturbation Training to Enhance NM Control

19 Core Stabilization Establish Core Stability

20 Hamstring Muscle Training Hamstring Muscle Training Hamstring Muscle Training Hamstring Muscle Training

21 ACL Rehabilitation What You Need to Know Step Down Test Hamstrings, Hamstrings & Hamstring Control Drop Vertical Jump Drop Vertical Jump Drop Vertical Jump Train the Uninjured Extremity Too!!

22 Hewett, Lidenfeld, Noyes: AJSM 99 Prospective study Trained high school athletes (ages 14-18) Trained group: n= 366 Untrained group: n=463 Athletes were soccer, basketball, volleyball 6 week program monitored by ATC & CSCS Program drills Hewett, Lidenfeld, Noyes: AJSM 99 Program components: Plyometrics, strength training & flexibility Emphasis on technique: proper alignment, body mechanics Reduced rate of injury in trained group 2.4 to 3.6 times higher injury rate in untrained group» 5 ACL injuries in untrained group» 0 ACL injuries in trained group Hewett, Lidenfeld, Noyes: AJSM 99 Specifics of program: Coaches & ATCs were instructed in implementation of the program using video tape & manual documenting compliance Training sessions: min a day, 3 x wk on alternating days Participates documented repetitions, etc 70% of athletes completed all parts of 6 wk program

23 Hewett, Lidenfeld, Noyes: AJSM 99 Specifics of program: 3 phased program: I: technique phase: 2 wks instructed on proper technique demos & drilled II: Fundamental phase: 2 week building a foundation of strength, power & agility III: Performance Phase:2 wks focused a achieving maximal vertical jump Jump Training Program Table PEP Program Mandelbaum, Silvers, et al: AJSM 05 Prospective non-randomized study Trained soccer players (ages 14-18) Study conducted over 2 yrs Trained group: n= 1885 Untrained group: n=3818 Programs utilized: stretching, strengthening, plyometrics, agility drills Significant reduction in injury rate» 88% reduction in ACL injury 1 st yr» 74% reduction in ACL injury 2 nd yr» 10 times greater risk of ACL injury in untrn grp PEP Program Mandelbaum, Silvers, et al: AJSM 05 Program emphasis: heavy emphasis on proper technique Soft landing, deep knee flexion, avoid flat foot landing, or knee in extension Program was a 20 min warm-up Utilized video tape & written packet Education for coaches

24 Soderman, Werner, et al: Knee Surg Traumatol Arthrosc 2000 Prospective randomized study Trained Swedish soccer players (20 yrs+/- 5) Trained group: n=121 Untrained group: n=100 Training program: daily for 30 days prior to season then 3x in season No significant difference in injury rates between groups Soderman, Werner, et al: Knee Surg Traumatol Arthrosc 2000 Program consisted of balance training, single leg stance min balance board drills Given their own board Home program compliance factor 3 x 15 on each leg 37% drop-out rate in intervention group Myklebust, et al: Clin J Sports Med 03 Prospective non-randomized study Trained Norwegian team Handball players Players ages yrs Analyzed over 3 yrs period (compared yr 1 to yrs 2 & 3) Trained players=1000, untrained = 1587 Program: 3x week for 5-7 wks prior to season then 1 x week in season Results: significantly fewer non-contact injuries in the intervention group Myklebust, et al: Clin J Sports Med 03 Program consisted of:» Instructional video, posters, coaches responsible for compliance» Athletes must participant in 15 sessions» Drills: improve awareness of knee position, partner drills for feedback» Mat drills, balance, running & plyos» Knees over toes Emphasize on Neuromuscular training

25 Myklebust, et al: Clin J Sports Med 03 Program:» Floor Exercises: running & planting, backward run, single leg side jumps, run & cutting, partner pushing while landing from 2 leg jump» Mat Drills: 1 leg balance throws, step downs, jump landing with ball catch, partner push» Wobble board drills: 2 & 1 leg balance, partner pushes Ettlinger, Johnson, Shealy: AJSM 95 Educational Programs Developed a guided discovery instruction program whereas the subject is presented with carefully selected stimuli intended to lead to discovery on their own Program divided into 3 parts:» Avoiding high risk behavior» Recognizing potentially dangerous situations» Responding quickly & effectively to situations 4700 ski instructors & patrollers completed program Reduced injury rate by 62% over 3 yrs Petersen, et al: Arch Orthop Trauma Surg 05 Prospective non-randomized German female team handball players Trained group: 10 teams (134) Untrained group: 10 teams (142) Program: information about injury mechanism, balance board exercises, jump training 8 week pre-season program Significantly lower rate of injury (ankle & knee) Petersen, et al: Arch Orthop Trauma Surg 05 Incorporated elements from several programs: Hewett, Henning, Caraffa Balance board drills 2 & 1 leg stance, catch with partner, throw at goal, throws with eyes closed Jump exercises - fwd, bwd, side to side jumps, drop jumps onto mat, side to side jumps, eyes closed landing Caraffa et al: Knee Surg Sports Traumatol Arthrosc 96 Proprioception balance training program 600 Italian semiprofessional & amateur soccer players 20 min training program of increasing difficulty Study duration 3 soccer seasons 87 % reduction in ACL injury rate in intervention group compared to control

26 ACL INJURIES IN Preventative Programs Exercise has been shown to sign. Reduce ACL & LE injury rates Caraffa:Knee Surg Spts Trauma 96 Heidt: AJSM 00 Hewett:AJSM 99 Soderman:Knee Surg Spts Trauma 00 Perturbation training resulted in NM adaptations but strength training did not Lephart: ORS 03 McCroy: JOSPT 03 Plyometric training resulted in an increase of Quad strength, but no change in hamstring or hip adduction strength Lephart:ORS 03 ACL INJURIES IN Preventative Programs Movement patterns can be modified, ground reaction forces reduced through intervention programs Cowling:JOSPT 03 Hewett:AJSM 96 Prapavess:JOSPT 03 Wojtys:AOSSM 02 Educational programs can affect injury rates(skiers) Ryder,Johnson:J Spt Rehab 97 Skolnick: JAMA 96 Feedback provided successful reinforcement of movt strategies Onate: JOSPT 00 Thank You!!!!!