Youth Sport Injuries: Early specialization vs Multi Sport Athletes Alaska Coaches Clinic 2014

1. Youth Sport Injuries:Early specialization vs Multi Sport AthletesAlaska Coaches Clinic 2014 Mark Evans Flanum, MD

2. Sport Specialization Intensive year round training in one sport at the exclusion of other sports Early specialization may lead to overuse injury and burnout

3. Life in 2014 • Recent contracts for professional athletes for millions of dollars • Alex Rodriguez 275 million • Youth sports are big business • Coaches, personal trainers, club team organizations, sporting goods stores/manufacturers, tournament organizers

4. Need to balance needs and desires of kids with desires of adults involved • Reflected glory • Dreams of kids • Dreams of adults

5. Alaska loves hockey • My son Noah started playing at age five • By age seven, expectation was having him skate five days per week • By age nine he decided he was done with hockey “for now”

6. Outline • Case presentations • Background • Definitions • Epidemiology • Risk factors (intrinsic and extrinsic) • Readiness for sport • Sport specialization • High risk overuse injuries • Burnout • Prevention

7. Case 1 • History • 10 year old girl presents for bilateral foot pain, right > left • Gradual onset of pain for 2 months, no injury • Active in dance all year round, 5 days per week, 1-2 hours per day • Hip hop, ballet, jazz • Pain worsened after an 8 hour competition • Walks with a slight limp now, favoring the right foot • Locates the pain over the medial mid-foot • Exam • Bilateral flexible flat feet with hind-foot pronation • Tenderness along the medial border of the navicular, right worse than left

8. Case 1

9. Case 1

10. Case 2 • History • 14 year old male from South Anchorage High presents after participating in weight lifting and feeling a “pop” during dead lift • Reports severe low back pain with right sided leg pain • Driven personality • Passionate about football and trains year round • Exam • Positive straight leg raise • Numbness on dorsum of right foot • Slight weakness of right EHL

11. Case 2

12. Lumbar MRI

13. Background • Youth sports is an American tradition • Life was simpler thirty years ago • Cars did not have shoulder belts • We did not wear helmets for biking and skiing

14. Background • Youth sports is an American tradition • Life was simpler thirty years ago • Cars did not have shoulder belts • We did not wear helmets for biking and skiing • Not all memories are good ones • Time are changing.

15. Background • Youth sports participation offer many benefits such as development of self-esteem, peer socialization, leadership, and general fitness. • However, there has been widespread emphasis on competitive success – selection to elite-level travel teams, collegiate scholarships, Olympic and National teams, and even professional contracts. • This has resulted in increased pressure to begin high intensity training at a young age. • Such emphasis on high intensity training for competition and winning at a young age rather than skill development can lead to overuse injuries and burnout.

16. Overuse injuries • Repetitive submaximal loading of the musculoskeletal system when rest is not adequate for structural adaptation. • Injury can involve the muscle-tendon unit, bone, bursa, neurovascular structures, and physis. • Young athletes are unique in that injuries can include the apophysis and physis.

17. Anatomy of bones Apophysis

18. Burnout • A spectrum of conditions that include overreaching and overtraining. • Occurs as a result of chronic stress that causes a young athlete to cease participation in a previously enjoyable activity.

19. Epidemiology • 60 million children between 6 to 18 years of age participate in some type of form of organized sports, 44 million in more than 1sport (National Council of Youth Sports, 2008) • 27 million children between 6 to 18 years of age participate in team sport (Sporting Goods Manufacturers, 2011) • Little research in incidence and prevalence of overuse injuries in children and adolescents • 3.5 million children are injured playing sports/recreation annually • Prevalence of overuse injuries varies by sport – 37% (skiing and handball) to 68% (running)

20. Risk Factors • Intrinsic • Growth-Related Factors • Susceptibility of growth cartilage to repetitive stress • Adolescent growth spurt • Previous injury • Previous level of conditioning • Anatomic factors • Menstrual dysfunction • Athlete specific psychological and developmental factors • Extrinsic • Training workload (rate, intensity, and progression) • Training and competition schedules • Equipment/footwear • Environment • Sport technique - biomechanics • Parental/coach/peer influences

21. Intrinsic Risk Factors – Growth and Development • Physical growth and cognitive development both influence successful participation in sports • Body mass and height increase in preadolescent and adolescent years – girls peak at 15, boys peak beyond 18 • Overuse injuries may be more common during the adolescent growth spurt – growth cartilage is less resistant to physical stress • Distal radius fractures, stress fractures, low back pain • Decrease in age-adjusted bone mineral density occurs before peak height velocity • Imbalances in growth and strength, lack of lean tissue mass, and joint hypermobility • Changes to the metaphyseal blood supply to the physis

22. Intrinsic Risk Factors – Anatomic Alignment • Patellofemoral malalignment • Pes planus • Pes cavus • Elbow hyperextension • Lumbar lordosis • Joint hypermobility • Frequently cited but poor evidence to support argument of malalignment causing injury

23. Intrinsic Risk Factors – Flexibility • Inflexibility of the muscle-tendon unit that develops during the adolescent growth spurt may contribute to injury • Causal relationship between flexibility and injury risk has not been documented • Mixed results in pre-exercise stretching on injury risk

24. Intrinsic Risk Factors – Biomechanics • Limb length, body mass, and moments of inertia change during adolescent growth spurtaffecting coordination and movement • There is suggestion that sport-specific changes in ROM play a role in overuse or biomechanical adaptation • Overhead athletes decrease dominant arm IR with strengthening internal rotators • One study of Peewee ice hockey players performing sprint start showed at risk hip kinematics which may lead to FAI and labral stress

25. Intrinsic Risk Factors – Strength and Conditioning • Children without foundation of general strength, endurance, and motor skills at increased risk for injury • Modifiable risk factors include poor endurance and lack of preseason preparation

26. Intrinsic Risk Factors – Menstrual Irregularity & Low Energy Availability • Female triad: • Eating disorder / Inadequate calories • Amenorrhea / oligomenorrhea / hypoestrogenemia – • Decreased bone density – increased fracture risk • History of amenorrhea comes with a risk of bone stress injury • Study of collegiate female distance runners found a linear relationship between number of menses per year and risk of stress fracture

27. Extrinsic Risk Factors – Workload • Linear relationship between hours of sports participation and risk of injury – study of 2721 high school athletes • > 16 hours per week increased risk of injury • Pitch volume has greatest association with injury rate in youth baseball • Youth pitchers who pitched > 100 innings/year were 3.5x at risk for injury and time lost • Young gymnasts with increasing skill level and number of hours training/week were at increased risk for wrist pain

28. Extrinsic Risk Factors – Scheduling • Year round involvement in sport or participation in multiple teams in the same sport • Elite young soccer players < 14 yo were at more risk for injury early in the season, compared to older players • Younger players may not have achieved optimal fitness and/or experiencing high training volumes or intensities • Overuse injuries were 42% higher in high school athletes who participated all year round vs <=3 seasons • Tournament scheduling may put young athletes at risk for overuse injuries

29. Extrinsic Risk Factors – Equipment • Lacking data to associate equipment and overuse injuries • Racquet sports – grip size and string tension • Weight and length of bats • Bike size • Shoe type and fit

30. Readiness for Sport • Matching child’s growth and development (motor, sensory, cognitive, social/emotional) to the tasks of sport • Coaches and parents often lack the knowledge about development • Ex: Enrolling a 5-year-old boy in tackle football • Readiness cannot be determined by age, body size, or maturation • Ex: Soccer requires being able to stand on one leg and swing the kicking leg / Baseball : eye tracking to hit a ball • Cognitive development important in understanding rules of the game (ex: staying in position) • 2-5 yo (limited fundamental skills and balance), 6-9 yo (running, swimming, skiing, soccer, baseball), 10-12 yo (football, basketball, hockey, volleyball)

31. Sports Specialization • An intensive, year-round training in a single sport at the exclusion of other sports. • This is a normal process as athletes mature and demonstrate talent in a sport or activity • However, this normally occurs in the late teens or early twenties • Occurs along a continuum. • Most important question is if they have quit other sports to focus on one sport

32. Does early specialization lead to success? • Growing concern regarding negative effects of early sports specialization – overuse injuries and burnout • No evidence of need to specialize at young age for most sports • Gymnastics, figure skating, swimming/diving may show benefit for early specialization and peak performance prior to maturation but have high rates of burnout and injury • Suggestion 10,000 hours required to become elite level athlete but this can be done at later ages

33. Does early specialization lead to success? • Several studies suggest diversified sports in early to mid adolescence may be more effective in developing skills • More world class athletes started at later age and competed in other sports at young age (Vaeyens et al 2009) • They recommend holding off on sports specialization until late adolescence (after age 15) • Need more data to link early sports specialization and injury

34. Who influences decisions? • Recent survey elite young athletes • Parents are strongest influence on initiation of sport • But coaches are biggest influence on decision to specialize in a single sport and perform intense training • Parents are proud don’t want to interfere with child-coach relationship • So coaches needs to be aware of risk of specialization

35. Cross training has many benefits • Early diversification provides valuable physical, cognitive and psychosocial environments and promotes motivation • Studies have shown greater number of different activities the athete experiences during development, translate into less sport specific practice necessary to acquire expertise in their desired sport • Early diversification associated with more enjoyment, fewer injuries ad longer participation • Lynn Young story on recuiters seeking multisport athletes

36. However being a multi sport athlete does not always PREVENT a bad outcome Bruce Jenner

37. High Risk Overuse Injuries – Spine • Stress fracture of the pars interarticularis • Most common at L5 • Occurs in6 of population • Gymnasts, football linemen and dancers at increased risk • Pain increased with extension • Initial treatment is activity modification and bracing • No risk of spondylolisthesis if unilateral • Surgical fusion may be needed if instability (spondylolisthesis) develops

38. High Risk Overuse Injuries – Femoral Neck • Uncommon in children and adolescents • Majority are compression sided • Tension sided – very high risk – requires strict NWB, +/- ORIF due to high risk of non-union, progression, AVN

39. High Risk Overuse Injuries – Patella • Several case reports, incidence unknown • 4-6 weeks in long leg cast or knee immobilizer

40. High Risk Overuse Injuries – Anterior Tibia • Tension-sided injury with high rates of non-union • “Dreaded black line” • Treated with activity modification, bracing , cast, bone stimulator and surgery for non-union or failure of conservative care

41. High Risk Overuse Injuries – Ankle • Medial Malleolus - Rare • One case report of a 15-year-old elite gymnast initially treated with rest with gradual RTP. Two months later had complete fracture, treated with ORIF. (Nyska, 2002)

42. High Risk Overuse Injuries – Foot • Tarsal navicular • Track and field, football, soccer (Ostlie, Simons, 2001) • Sesamoid • Bone scan and CT are helpful in making the diagnosis • Excision after failure of non-op therapy, RTP within 6 months (Biedert, Hintermann, 2003) • 5th MT metaphyseal/diaphyseal junction • No data in children Sesamoid

43. High Risk Overuse Injuries – Physeal Stress Injury • Most physeal stress injuries resolve without complications • Proximal humerus, distal radius, distal femur, and proximal tibia • High risk – distal femur and proximal tibia – may result in leg-length discrepancies, angular or rotational malalignment (Green, Swiontkowski, 2003) • Gymnasts’ wrist – premature closure may lead to positive ulnar variance (compression of TFCC, DJD, chronic ulnar sided pain) (Albanese et al., 1989) • Knee – one athlete developed bilateral genu varum over two years following physeal injury (Laor et al., 2006)

44. High Risk Overuse Injuries – Osteochondritis Dissecans • Defect in subchondral bone and articular cartilage • Femoral condyles, capitellum, talar dome • MRI is helpful in staging lesions • Stable lesions in skeletally immature athletes can be treated non-operatively • Surgery for unstable or skeletally mature • Gymnastics, soccer, basketball, lacrosse, football, tennis, squash, baseball and weight lifting may put participants at a higher risk of OCD

45. High Risk Overuse Injuries – Apophyseal Injuries • Most apophyseal stress injuries resolve when physis closes • However some can persist as an ossicle and pain • Tibial tubercle, medial epicondyle, ischial tuberosity, olecranon apophysis, base of the 5th MT • Incidence of non-union is unknown • Ossicle resection can provide relief of pain

46. High Risk Overuse Injuries – Effort Thrombosis • Paget-Schroetter Syndrome • Clot in subclavian or axillary vein • Unilateral arm swelling and discoloration • Follows sporting activities, such as wrestling, playing ball, gymnastics and swimming, • It is believed that retroversion, hyperabduction and extension impose undue strain on the subclavian vein leading to microtrauma

47. Burnout • Overreaching – functional or nonfunctional – intense training that leads to decreased performance, resolves with a rest period. • Overtraining – extreme nonfunctional overreaching, longer period of decreased performance (over 2 months), maladaptive physiology, more symptomatic

48. Burnout – Risk Factors

49. Burnout - Symptoms DiFioriet al., 2014

50. Burnout • Study showed that swimmers who specialized early spent less time on national level team and retired from sport earlier • Gymnasts who specialized earlier rated their health lower and experienced less fun in the sport