New Insights into Injury Prevention in Elite Youth Tennis - PowerPoint Presentation

New Insights into Injury Prevention in Elite Youth Tennis Neeru Jayanthi, M.D.Associate Professor Orthopaedics and Family Medicine Director Tennis MedicineEmory University Sports Medicine CenterPresident, STMS STMS-Web.org

Tennis Injuries?

OBJECTIVES

INJURY PREVENTIONNo known interventional study on injury prevention in junior elite tennis players!

Parental/Coach Influence on Training Elite British young athletes (soccer, tennis, gymnastics, swimming) Most powerful influence to do intensive training: (TENNIS ONLY)1. Coach (45%)2. Child (35%)3. Parent (15%)Baxter-Jones, Mafuli, J Sports Med Ph Fit, 2003

Training profiles of US Junior Elite

US JUNIOR TENNIS We have no self-regulation of injury risk in US junior tennisThere is a volume-based point ranking system

Quantifying Injury Risk LEVEL OF RISKRISK OF ATHLETERISK OF INJURYSPORTS PARTICIPATIONHIGHSPECIALIZED HIGH VOLUME >10-16 hrsHIGH COMPETITIONPRIOR INJURY (back)RAPID GROWTHOLDER, MALE>4th match in tournament SPONDYLOLYSISSTRESS FRACTURESGROWTH PLATEOCDRESTRICT INTERMEDIATE LOW SPECIALIZE INTERMEDIATE GROWTH INTERMED VOL.APOPHYSITISAPOPHYSEAL AVULSIONSINSTABILITYTEMPORARY RESTRICTIONS OR REDUCE LOWMULTIPLE SPORTSRECREATIONALLOW VOLUMESTATIC GROWTHPATELLOFEMORAL MUSCLE STRAIN TENDONITISMINIMAL RESTRICTIONS, AS TOLERATED

Injury Prevention Recommendations

Study DesignsDescriptive epidemiology Cross-SectionalAnalytical-Case ControlCase Series/Individual FactorsBiomechanical analysis

Epidemiology Injury rates have been documented in competitive junior tennis players:JayanthiHutchinsonSafranReeceDe SilvaHjelmKovacs Hashimoto

Population - Based Descriptive epidemiology (Trends)Safran (USTA) Hutchinson (USTA) Silva (Brazil), Hashimoto (Japan)Jayanthi (USTA) (medical withdrawals)CROSS-Kovacs (USTA)Risks: >5th tournament match Boys similar to girls injury rates Injured boys 1000 hrs/year

Injury Rates-Tournaments

Injury Locations-TournamentBack Thigh ShoulderHutchinson et al.We need to understand relationship of tournament volume better

RISK FACTORS FOR MEDICAL WITHDRAWALS IN USTA JUNIOR NATIONAL TENNIS TOURNAMENTS 28,336 match exposures analyzedSex (Males inj>females)14,108 male 14,105 female Age 7,056 in 12’s 7,002 in 16’s7,184 in 14’s 7,094 in 18’s Jayanthi et al, 2009

Results: Match Volume & Medical Withdrawal Incidence P<0.0001

MATCH SCHEDULINGCumulative match volume may be detrimental to young tennis player. We need to consider recovery in scheduling

24 youth athletes did not recover physiologic strain and perceived effort with one hour rest in between two 80 minutes cycling sessions in LAB (ideal environment)Bergeron, et al., 2009. 14 and under boys afternoon match winner predicted based on opponent’s minutes exposed to heat prior to match.Coyle, et al. 2006 SAME DAY COMPETITION

Sport Competition loadBetween-contests restTennis3 singles, 2 doubles matches/day1 h (singles), 30min (doubles) Bergeron, Michael, “Youth Sports in the Heat: Recovery and Scheduling Considerations for Tournament Play”, Sports Med , 2009.

Tournament Recommendations Exercise caution in junior tournament players competing in their fifth match and beyond, particularly in older age divisions (SORT Level B)Reduce size of some tournaments to Round of 32 or 64

Tournament Recommendations (Same Day) Consider having at least 1-2 hours between same day matches to allow for sufficient recovery. (SORT Level B)Cancel consolation for extreme heat conditions

Prospective Evaluations Analytic-Case Control (Evaluate Specific Risk Factors)Hjelm et al. (Sweden)Jayanthi (US)Hashimoto (Japan)Baxter-Jones (U.K.)Risks: Prior Injury (back) >10-16 hrs/week Sports Specialization

Hjelm (Sweden) 55 players over 2 years2.3 inj/1000 hr (boys)Risk factors for injury:,Previous injury (OR, 8.8), p=0.01> 6hrs/week for back (OR 4.7), p<0.04Total hrs/year (p=0.02) 446 hr/yr versus 246 hr/yr Ruiz-Cottaro (retrospective)66 cases of spondylolysis Spanish Tennis Federation>15 hours/week in all casesProspective Evaluations

Training and sports specialization risks in junior elite tennis players Neeru Jayanthi, MDAmanda Dechert, MS2Amy Luke, PhDRamon Durazo-Arvisu, PhDLoyola Stritch School of Medicine

Summer Tournament Play 540 players consented 519 sufficiently completed baseline survey 498 did NOT medically withdraw 21 medically withdrew Methods Design: Prospective cohort study

“Training and Sports Specialization Risks in Junior Elite Tennis Players,” Jayanthi, Dechert, Luke et al.

Months/Year Competing P<0.9

Results Increased medical withdrawalrisk and:Players who specialize only in tennis (p = 0.047)Players who have had an injury or illness in the past year (p < 0.001) (5.4x increase) Playing >16 hours week may be risk factor for development of medical withdrawal

Training RecommendationsCaution when playing >10 hours/week history of prior injury, particularly in the low back and before a tournament (SORT Level B).Hjelms, Kovacs, Jayanthi et al.Participate in less tennis hrs/week then your age to prevent overuse injury (SORT B)Jayanthi, et al.

Risks of Sports Specialization and Rapid Growth in Young Athletes 1191 athletes150 tennis players (12% of all athletes)91 specialized tennis players (61%)Jayanthi et al., 2014

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Study Sport(s)Athletes Evidence for (+): Study conclusions       Begin intense training before age 12 Specialize before age 12Begin intense training after age 12Diversify early, specialize after age 12  Hume 199426Rhythmic gymnastics106 across all levels+   + Amount of gymnastic training during development is related to level of attainment. All gymnasts participated in other sports, with no difference between elites and sub-elites. Enjoyment of gymnastics was strong predictor of attainment. Law 2007 31 Rhythmic gymnastics 6 elite 6 sub-elite + +     Elites and sub-elites began intense training at similar ages, but elites were involved in fewer other activities from age 4-16, and accumulated more hours training by age 16. Helsen 1998 23 Men’s' soccer, Men’s' field hockey 33 international 39 national 52 provincial     +   Soccer began practicing at age 5, field hockey at age 9. Hours spent in practice were similar among levels until age 12. After age 12, international players spent more time in practice than national players, and national players spent more than provincial players. Hodges 1996 25 Wrestling 21 elite 21 club-level     +   Elite wrestlers spent more time training after age 16 compared to club-level wrestlers. However, since all subjects began intense training at 13.2 + 0.6 yrs, comparison to early intense training (before age 12) not possible. Soberlak 2003 44 Men’s' ice hockey 4 elite     + + Elite players intensified their deliberate hockey training in late adolescence and played other sports during developmental years Carlson 1988 13 Men's and women's tennis 10 elite 10 near-elite     + + Elite players began intense training and specialized later (after age 13-15) than near-elites (age 11). Lidor 2002 32 Various men’s' and women’s' sports 63 elite 78 near-elite     + + Elite more likely than near-elite athletes to begin intense training after age 12 and to have played >1 sport during developmental years. Gullich 2006 22 Olympic sports 1558 German athletes from Olympic promotion programs     + + Elite athletes began intense training and competition in their sport later than near-elites (11.4 yrs vs 10.2yrs and 13.1 vs 12.0). More elites participated in >1 sport from age 11 than near-elites (64% vs 50%). Moesch et al. 2011 39 Sports measured in cms, gms or secs* 148 elite 95 near-elite     +   Elite athletes began intense training at a later age compared to near-elites. Near-elites accumulated more hours of training by age 9, 12 and 15 than elites, while elites accumulated more training by age 21 than near-elites. Baker et al. 2003 5 Men's and women's field hockey, Men's basketball, Women's netball 15 elite 13 near-elite     + + Elites accumulated more hours of sport-specific practice from age 12 years onwards. However, all subjects began intense training at about age 12, so unable to compare to an early intense training group. Elites had broader range of sports experiences throughout their careers compared to near-elites. Barynina 1992 6 Men's and women's swimming Elite Russian swimmers (number not reported)       + Swimmers who began specializing before 11 yrs of age spent less time on national team and retired earlier than later specializers. Wall 2007 47 Boys' ice hockey Parents of 8 minor league players (mean age 13.9 yrs) and 4 ex-minor league players (mean age 14.5 yrs)     +   Dropouts began off-ice training earlier than non-dropouts (11.75 vs 13.8 yrs of age) and spent more hours in off-ice training (107 vs 6.8 per year). Both groups participated in a similar number of other sports (4.75) from 6-13 yrs of age. *Canoeing/kayak, cycling, orienteering, rowing, sailing, skiing, swimming, track and field, triathalon , weightlifting

FACTORS FOR ELITE SUCCESSElite Soccer players More unstructured free play between ages 6-12Elite Tennis PlayersSame CoachLess overall demands for success

Defining Sports SpecializationIntense Year Round Training in a Single Sport at the exclusion of other sportsJayanthi et al., DiFiori et al.

Rates and Degrees of Specialization 38%34% Jayanthi, et al.

Jayanthi, et al. % Low specialized 47.7% 34.4% 38.2% p<0.001 % Moderately specialized 30.7%34.9%33.7%p<0.001%Highly specialized 21.6%30.7%28.1%p<0.001Uninjured(N=368)Injured(N=822)Total(N=1,190)P-value

Sports Specialization Training Risks

Competitive Tennis players

Specialization RecommendationsConsider delaying specialization in tennis until middle or late adolescence for injury prevention as well as for successful performance (SORT Level B) There may be a risk of early specialization in tennis.Consider delaying specialization beyond pre pubescent ages.Reduce your sports training ratio <2:1

Injured Tennis Players (p=0.01). Jayanthi , et al., unpublished

Tournament Volume Recommendations Annually, consider playing <40 competitive SINGLES matches/yearConsider 1-2 tournaments/month (SORT C)

Training for success Retrospective review of top 10 men’s players and mean number of tournaments17 y/o = 11.018 y/o = 15.2Reid M et al. 2009Successful elite playersTrain less <15 y/oHave same coachFewer demands for successCarlson, et. al. 1985

Individual Risks Physical evaluations (strength, flexibility)EllenbeckerRoetertKovacsHjelms No clear link to injury riskInjury RisksJayanthi Risk of sports specializationHjelms Risks with low back Stroke EvaluationsGomez KiblerKovacs Fleisig Can have increased loads/stress shoulder/elbow Abrams/ Safran Can have increased loads/stress shoulder

Asymmetric Tennis PlayerStructural EvaluationsAsymmetric tennis player GIRDWrist, forearmRectus, iliopsasEllenbecker, Roetert, Hjelm, Kibler, Baxter-Jones, Cools/Johannsen assessmentsUnclear relationship to injuryCan improve GIRD (Kibler)Serial MRI’s lumbar spine85% with abnormalitiesSpondylolysisTurner, et. al

Serve-Kinetic Chain Leg Drive-->Trunk rotation-->Rapid shoulder internal rotation-->Forearm pronation-->wrist flexion-->Arm adductionLegs/trunk: 54%Shoulder: 21%Elbow: 15%Wrist: 10%From Kibler, WB,1995

Stroke changes and injury riskUpper Extremity Jayanthi, Esser, CSMR, 2013Lumbar spineThere is no known interventional study testing biomechanical changes and injury risk in junior elite players!

Biomechanical Risks13 yr old appropriate age for kick serve (SORT C)Increased lumbar spine forcesKick serve places higher demands on the low back and shoulder AbramsMore shoulder and elbow stress with limited knee bend (<10 degrees)Fleisig, et al.Recommendation: Delay kick serve until after age 13 to reduce stressful loads (SORT C)Kovacs, Abrams

USTA 4: Evaluation of Junior USTA Players Injury Risk Using a Novel Weekly Electronic Survey Neeru Jayanthi, MD, Calloway Robertson MS2, Lara Dugas, PhDLoyola Stritch School of Medicine

STUDY DESIGN16 elite junior competitive tennis players (13 F, 3 M) completed baseline survey Complete weekly electronic survey x 10 weeks during tournament season

Training volume and risk of injuryHigher weekly training volumes in uninjured players (14-15 hrs/wk vs. 11-12 hrs/wk) (p<0.010)

USTA 4-ResultsThose that had lower off court training (1 or less hrs /week) were more likely to get injured (p<0.067) May be protective of higher volumes of tennisConsider >1 hour at least of off court training/injury prevention

10 and under tennisWhat effect will this have on cumulative volume in the next generation of elite juniors?

Ideal Training Program12 y/o junior tournament player < 12 hrs/week<12 tourn/yrPossibly consider another sport (soccer) with an off-season for tennis2+ hrs/week injury prevention training, etc. THIS IS NOT POSSIBLE IN CURRENT RANKING SYSTEM TO MAINTAIN A HIGH RANKING

Summary of Recommendations

FUTURE RESEARCHThere are no interventional injury prevention studies in junior tennis players Tournament scheduling (recovery)Same day matches10 and under tennisTransition ballsGrowthAttritionSpecialization

Thank You!                  IOC WORLD CONFERENCEPREVENTION OF INJURY AND ILLNESS IN SPORT