APA 4118 paedatric Sports Biomechanics

What is the impact of lower muscle mass and strength in children?

It can lead to less capacity to recruit type-II motor units.

can we treat children as small adults?

no

• Bodies still developing

  • Changing movement and mechanics

  • Differences in muscle mass, bone structure, and motor control

  • Impacts performance and risk of injury

What type of muscle fibers are more prevalent in early-mid childhood?

Higher proportion of type I fibers.

what are some unique properties of children’s bones?

• more flexible

• more porous

• unsealed epiphyseal plates

• higher cartilage content

• continuing ossification

wha is the reason for observed muscle differences in children

less capacity to recruit type-II motor units

How do children's tendons differ from adults' tendons?

Children's tendons are more elastic.

What is the effect of reduced efficiency of force transmission in children?

It affects their overall strength and performance.

What is joint laxity?

Less stiff ligaments leading to more lax joints.

What percentage of girls experience hypermobility?

32.5% of girls.

What percentage of boys experience hypermobility?

18.1% of boys.

What age range is associated with increased injury risk in adolescence?

~10-18 years.

What happens to bone mineral density during peak growth velocity?

Cortical shell strength development slows, growth rate outpaces corticalization of trabecular bone at growth plate, decline in bone mineral density.

What happens to muscle mass during adolescence?

There is a sudden increase in muscle mass and force production therefore inc likelihood of acute injuries

What happens to tendon/ligament elasticity during adolescence?

Elasticity decreases, increasing the risk of sprains/strains.

What physical changes occur in males during adolescence?

Broadening of shoulders.

What physical changes occur in females during adolescence?

Broadening of hips, larger Q angle

What characterizes an acute injury?

It is traumatic and caused by a single event.

What types of injuries are included in acute injuries?

Ligament sprains, muscle strains, fractures, dislocations.

What characterizes a chronic injury?

It is caused by overuse, where training demands exceed the body's ability to heal. Microscopic tissue damage

Who is at higher risk for chronic injuries?

Children and adolescents due to weaker physes/cartilage, muscular imbalance, and lack of coordination, growth spurts

What is sport specialization?

Year-round intensive training in a single sport at the exclusion of all other sports.

What do medical societies advocate regarding sport specialization?

They advocate against it due to limited studies on its effects on injuries. Possible small increase but more evidence needed

What is 'Little League Shoulder'?

Epiphysiolysis of the proximal humerus, often seen in young baseball pitchers. Causing weakness. One of the most common causes of throwing-related shoulder pain in skeletally immature populations

What causes 'Little League Shoulder'?

Widening of the proximal humerus physis due to time of maximal physeal growth.

What are common risk factors for 'Little League Shoulder'?

Increased physical size, range of motion deficits, shoulder strength imbalance, poor pitching mechanics. lax ligaments at the humeral physis before 17-18 yrs. Large external rotation torques on shoulder, repetitive microtraume leading to deformation of epiphysis.

What is the significance of humeral retroversion in young athletes?

Normal at birth but reduces through adolescence, except in throwers where it is delayed, causing stress due to opposing forces during throwing.

posterior glenoid dysplasia

theory: occurs in addition to little league shoulder. 97% of youth baseball players w/painful shoulder have.

• inferior 2/3 of glenoid is last to ossify and fuse

• throwing demands may lead to posteroinferior glenoid rim + dysplasia(may inc recovery)

treatment

• rest, PT, imp pitching mechanics

What is 'Gymnast Wrist'?

Distal radial physeal stress syndrome caused by repetitive stress in wrist extension (inflammation of the physis + microtrauma), can lead to premature closure of radial physis+ overgrowth of ulna)

pelvic avulsion injury

Avulsion fracture of the apophyses due to internal muscle forces.

What are the symptoms of pelvic avulsion injuries?

A feeling of a 'pop' with immediate pain and weakness.

What is the typical recovery process for pelvic avulsion injuries?

Often recovery occurs without surgery, taking several months; surgery is needed if the fracture is displaced over 3cm.

What is a common treatment for shoulder injuries in youth baseball players?

Rest, physical therapy, and improving pitching mechanics.

What is the consequence of repetitive microtrauma in young athletes?

It can cause deformation of the epiphysis and lead to injuries.

What is the last part of the glenoid to ossify?

The inferior two-thirds of the glenoid.

What are the potential long-term effects of glenoid dysplasia in youth athletes?

It may lead to instability, injury, and longer recovery times.

What was the total number of fractures reviewed at Boston Children's Hospital from 2005-2020?

719 fractures in 709 patients

What percentage of avulsion fracture cases were male?

78%

During which phase of growth do fractures occur most frequently?

During a narrow window of skeletal maturity with peak growth velocity

What theory explains the relationship between bone growth and muscle tightness?

Bone growth causes relative tightness/contractures of muscles

What is a discoid meniscus?

A congenital condition characterized by a thicker, discoid shaped meniscus

What are common symptoms of a discoid meniscus?

Pain, stiffness, catching/locking of knee, instability, reduced range of motion (ROM), may be asymptomatic

What is the surgical treatment for a discoid meniscus?

Saucerization or partial meniscectomy

What risk does partial meniscectomy pose?

Increased risk of osteoarthritis (OA)

What is osteochondritis dissecans?

An idiopathic injury to the blood supply of the subchondral bone leading to separation of a bone fragment (can damage cartilage)

Where is osteochondritis dissecans most commonly found?

In the knee

What are early symptoms of osteochondritis dissecans?

Pain, swelling, and limping

what are causes of OCD

biologic (genetic, ossification centre deficit, endocrine disordfers), mechanical: Injury/overuse, tibial spine impingement, discoid meniscus, biochemical alterations

What are late symptoms of osteochondritis dissecans?

Decreased range of motion, catching/locking of knee, constant pain

What is the likelihood of skeletally immature patients healing without surgery for osteochondritis dissecans?

More likely to heal without surgery, treatment is rest + activity modification

What are some surgical options for osteochondritis dissecans?

Drilling to stimulate healing, fixation to stabilize the fragment, or resurfacing if the fragment is not salvageable

What is patellofemoral instability?

A condition associated with partial subluxation or complete dislocation of the patella from the trochlear groove

What is the common direction of patellar dislocation?

Almost always lateral

What percentage of patellofemoral instability cases occur during sports?

66%

What percentage of patellofemoral instability cases are non-contact?

96%

What are the conservative treatment options for patellofemoral instability?

Physiotherapy, bracing, activity modification

What are some surgical treatment options for patellofemoral instability?

MPFL reconstruction, tibial tubercle osteotomy, trochleoplasty

What is the chance of redislocation after the first incident of patellofemoral instability?

31% chance of redislocation

what are some risk factors of patellofemoral instability

• major: patella alta, excessive patellar tilt, trochleas dysplasia, increased TT-TG distance

• minor: dysplastic VMO muscle, overpull of lat structures, insufficitnt MPFL