Hamstring strains and prevention

Transcription

1 Research Center of Movement Science Department of Physiotherapy University of Iceland UIVERSITY OF ICELAD DEPARTMET OF PHYSIOTHERAPY Hamstring strains and prevention Árni Árnason PT, PhD University of Iceland, Department of Physiotherapy Gáski physiotherapy clinic What are the causes of injury? What are the causes of injury? What can we do to prevent injuries?

2 Rate of hamstring strains out of all injuries Incidence of hamstring strains /1 hours Type of sport Sprinting Australian Rules Soccer (male) Soccer (female) Match 11-16% Training 7-14% Total 29-38% 14-15% 1-16% Type of sport Australian Rules Rugby Match Training.3 Total Rugby 1% Soccer American 5% Location of injuries in elite male soccer - Iceland = Injuries in thigh - Iceland =59 Muscle strains Contusions Other umber of in 1 Head/n Other Foot Leg Ankle Knee Thigh Groin Back Abdomen Arms umber of injuri 5 Anterior Posterior Medial Lateral Thigh umber of injuries umber of strains and sprains - 17 male teams in Iceland Hamstring Quadric. Groin Other Knee Ankle Other Muscle strains =12 Ligament sprains Location of hamstring strains Verrall et al 26 Woods et al 24 Kolouris & Connell 23 Slavotinec et al. 22 DeSmet & Best 2 Garrett et al 1989 Sport Australian Soccer Australian Biceps 87% 53% 69% 87% 6% 58% Semitend 15% 5% 5% 2% 8% Semimem 12% 7% 7% 17% ot identified 19% 14% 17%

3 Garrett et al 1989 Location of hamstring strains Verrall et al 26 Woods et al 24 Kolouris & Connell 23 Slavotinec et al. 22 DeSmet & Best 2 Sport Australian Soccer Australian Biceps 87% 53% 69% 87% 6% 58% Semitend 15% 5% 5% 2% 8% Semimem 12% 7% 7% 17% ot identified 19% 14% 17% Why biceps? Some possible explanations Biceps femoris Caput longum two joint muscle Caput breve one joint muscle Innervation Caput longum: n. tibialis (S 1, S 2, S 3 ) Caput breve: n. peroneus communis (L 5, S 1, S 2 ) Semimembranosus: n. tibilais (L 5, S 1, S 2 ) Semitendinosus: n. tibialis (L 5, S 1, S 2 )??? Severity of hamstring strains Brooks et al 26 Arnason et al 24 Sport Rugby Soccer Mild 1 week 37% 23% Moderate >1 3 weeks 37% 42% Severe >3 weeks 26% 35% What are the causes of injury? Average days absent because of hamstring strains: Rugby days (Brooks et al 26, Brooks et al 26) Soccer 18.1 ± 12.5 days (Arnason et al 24) Intrinsic risk factors: Age Gender Body composition (e.g. bodyweight, BMI, bone mineral density, BMD) Health status (e.g. previous injury, joint instability) Physical fitness (e.g. muscular strength, endurance, mobility) Malalignement Technical skill (e.g. coordination & balance Risk factors for injury Predisposed athlete Risk athlete Exposed to extrinsic risk factors: Human factors (e.g. opponent, referee) Protective equipment (e. g. helmet, shin guard) Sports equipment (e.g. shoes, cleats) External environment (e. g. weather, surface) Injury mechanisms Injury Inciting event: Playing situation Training- & match schedule Training programme Joint movement & -forces Risk factors for injuries methodological approach Multivariate approach Sample size To detect: Moderate to strong association: 2-5 injury cases Small to moderate association: about 2 injury cases Most studies published to day are too small to detect small or moderate association Meeuwisse WH: Clin J Sports Med. 4: , 1994 Bahr & Holme: Br J Sports Med. 37: , 23

4 Risk factors for hamstring strains in soccer Univariate analysis: Previous hamstring strains (Hagglund et al 26, Arnason et al 24, Arnason 1996) Increased age (Hagglund et al 26, Arnason et al 24, Woods 24) Descent (Woods 24) Decreased flexibility of hamstring muscles? (Witvrouw 23) Previous hamstring & groin strains Precentage p<.1 OR= %CI Previous hamstring strains ot previous hamstring strains p<.1 OR= %CI /74 9/442 1/19 7/414 Previous groin strains ot previous groin strains Am J Sports Med, 32 (suppl): 5-16, 24 Evidence based risk factors for hamstring strains in soccer Multivariate approach: Hagglund et al 26 Arnason et al 24 Variable Previous injuries Increased age Previous injuries Increased age OR % CI p <.1.1 <.1 <.1 Risk factors for hamstring strains in Australian Univariate analysis: Previous hamstring strains (Verrall et al 26, Gabbe et al 25, Bennell et al 1998) Increased age (Verrall et al 26, Gabbe et al 25) Larger size of previous hamstring injury identified on MRI was indicative of higher risk of recurrent injury (Verrall et al 26) Previous knee injury (Verrall et al 26) Aboriginal descend (Verrall et al 26) BMI (>25kg/m 3 ) (Gabbe et al 25) Reduced isokinetic consentric hamstring muscle strength (H/Q ratio) at 6 /sek (Orchard et al 1997) Evidence based risk factors for hamstring strains: Australian Multivariate approach: Gabbe et al 25 Gabbe et al 25 Verrall 21 Variable Previous injuries (12 mnd) Increased age (>24y) Increased age (>22y) Increased age Previous injuries Aboriginal decent OR/RR % CI p Injury mechanisms for hamstring strains in soccer Woods et al 24 Arnason et al 24 Sprint 61% 61% (19/31) Stretch 15% % Shoot 5% 1% (3/31) Other 19% (4/31) ot identified % 16% (5/31)

5 Injury mechanisms for hamstring strains in Australian Rule Gabbe et al 25 Sprint 81% Kicking the ball 19% Common injury mechanism when players are running on max or submax speed and bend forward to catch the ball When do hamstring strains occur during sprinting? EMG studies-sprinters Highest activity in hamstring muscles Late in swing phase right before foot strike (eccentric) Right after foot strike (eccentric to concentric) Case study Strain in biceps femoris, caput longum Subject: a professional male skier Method: running on treadmill at 5.4 m/s, inclination 15% Body kinematics were recorded at the time of injury Results: The injury period corresponds to the late in swing phase or very initial stance phase Injury mechanisms for hamstring strains in dancing Askling et al 22 Askling et al 26 Slow activities during stretching 88% (n=86) 1% (n=15) Powerful movements 12% (n=12) % Heiderscheit et al Clin Biom 2: , 25 What are the causes of injury? Evidence based risk factors for hamstring strains Increased age Previous injuries Aboriginal decent What can we do to prevent injuries?

6 Possible risk factors for hamstring strains Insufficient warm-up? Muscle fatigue late in the game or training? Inadequate H/Q ratio or decreased hamstring strength? Short hamstring muscles? Large size of previous hamstring injury (MRI) Previous knee injury? Increased BMI? erve root irritation? Injury mechanisms Sprinting Shooting / kicking a ball Slow stretching (dancing) Prevention of hamstring strains Only two published studies found!!! The importance of eccentric hamstring muscle strength Soccer training can predispose imbalance in H/Q ratio: Traditional soccer training can increase strength in quadriceps more than in the hamstrings (jumping, shooting, kicking, acceleration changes, etc.) Squat and knee extension are frequently used in strength training in soccer The most common method for training of hamstring is concentric strength training hamstring curl Yoyo flywheel training Yoyo flywheel training Method: RCT study of 3 male soccer players from two premier league soccer teams in Sweden Players with chronic hamstring injuries excluded Randomly divided in intervention (n=15) and control group (n=15) Intervention group: 1 weeks training of eccentric overload 1-2 times per week during preseason period or totally 16 sessions Injury registration during the following season Yoyo group Control group Consentric Eccentric I j i Control YoYo Askling et al. Scand J Med Sci Sports 13: , 23 Askling et al. Scand J Med Sci Sports 13: , 23

7 ordic hamstring lowers Week Exercise program ordic hamstring lowers Sessions/week Sets and reps 2 x 5 2 x 6 3 x x sets reps Mjølsnes et al. Scand J Med Sci Sports. 14: , 24 Strength training - change during 1 weeks training H ecc :Q cons ratio 3 ordic hamstring Hamstring curl conc extensors ecc flexors isom flex 9 isom flex 6 isom flex 3 Mjølsnes et al. Scand J Med Sci Sports. 14: , 24 H i / 1,2 1,1 1,,9,8,7,6,5,4,3,2,1, -,1 ordic hamstring Hamstring curl Before After Change Mjølsnes et al. Scand J Med Sci Sports. 14: , 24 Conclusion ordic hamstring lowers training in ten weeks is more effective to increase maximal eccentric strength in the hamstring muscles among players than similar program with hamstring curl exercise ordic hamstring takes short time and do not need a special equipments RCT of eccentric exercise to prevent hamstring strains Method: RCT study 22 players from seven amateur Australian Rule clubs Five sessions of exercices in 12 weeks Intervention group (n=114): 12 sets of 6 repetitions eccentric hamstring exercise Control group (n=16): stretching and movement exercises Mjølsnes et al. Scand J Med Sci Sports. 14: , 24 Gabbe et al. J Sci Med Sport 9: 13-19, 26

8 RCT of eccentric exercise to prevent hamstring strains Poor compliance less than 1% of participants finished all five exercise sessions o difference was found between groups The Icelandic-orwegian hamstring injury study Aim: To test the effect of eccentric strength training and flexibility training on the rate of hamstring strains in Gabbe et al. J Sci Med Sport 9: 13-19, 26 The Icelandic-orwegian study - the OSTRC hamstring strain prevention program 1 Warm-up stretch 3-component program: 1 Warm-up stretch Goal: Stretch towards maximal ROM 2 Flexibility training Goal: Increase maximal ROM 3 Eccentric strength training Goal: Increase strength Stretch hamstrings 3 x 2 s during warm-up before training sessions and matches 2 Flexibility training Stretch 3 x 45 s 3x per week before season 2x per week during season Separate sessions or after training 3 Eccentric strength training In the beginning: two sets - 5 reps After 3-4 weeks: three sets reps 3x per week before season 1-2x per week during season Separate sessions or after training

9 The Iceland-orway study - the OSTRC hamstring strain prevention program Iceland & orway: Hamstring injury incidence Iceland: Warm-up, flexibility & strength orway: Warm-up & flexibility 2 21 Iceland: Warm-up & strength orway: Warm-up & strength 22 Program followed Preseason only ot followed Iceland Follow up 21 orway 7 7 Iceland orway 6 8 Results - flexibility training Results - strength training,8,7, ,5 4, 3,5 p<.1 p=.3 Intervention teams Control teams Baseline seasons,5,4,3,2 3, 2,5 2, 1,5 1, p<.1 p<.1 p=.1,1,5 p=.7 Hamstri, Baseline season Intervention teams Control teams Hamstr, Matches Training Total Conclusion The overall incidence of hamstring strains was 65% lower among teams that used the eccentric strength training program and stretching during warm up compared to the other teams Eccentric strength training with ordic Hamstring is feasible not time-consuming and does not require special equipment The effect of the training program should be studied in a RCT study Prevention of hamstring strains Conclusion Eccentric strength training seems to have preventive effect against hamstring strains The effect of eccentric strength training programs should be studied in large RCT studies Other possible preventive measures should also been studied in RCT studies.

10 Tromsø 28 Oslo 25