MSK disorders

- Developmental dysplasia of the hip (DDH)- Legg-Calvé-Perthes disease (avascular necrosis of femoral head)- Slipped capital femoral epiphysis (SCFE)

developmental etiologies of limp

- Rickets (vitamin D deficiency)- Scurvy (vitamin C deficiency)- Gaucher disease- Hypothyroidism (rare)

metabolic causes off limp

SCFE

Obese adolescent with external rotation of leg →

Perthes disease

Gradual onset, painless limp in a 4–8-year-old →

breech

female sex (estrogen-mediated ligamentous laxity)

first born (tighter uterus)

family hx

oligohydramnios

postnatal positioning

risk factors of developmental dysplasia of the hip

Positive Ortolani maneuver (hip dislocation reducible) — “clunk” felt as femoral head relocates into acetabulum

Positive Barlow maneuver (hip dislocatable) — “clunk” felt as femoral head slips out posteriorly

Asymmetric thigh/gluteal folds

Apparent leg length discrepancy (Galeazzi sign: knee lower on affected side when hips/knees flexed)

presentation of developmental hip dysplasia in the newborn

Limited hip abduction

Painless limp or waddling gait

Leg length discrepancy becomes more obvious

presentation of developmental hip dysplasia

-pavlik harness worn conntinuously for several weeks in those under 6 months

-6-18 months: closed reduction

>18 months open reduction

tx of developmental dysplasia of the hip

pavlik harness

used for hip dysplasia in infants

Remove only to take baths

Screening: All newborns are examined at birth and at each well-child visit until walking; US screening for high-risk infants even if exam is normal.

screening recs for developmental dysplasia of the hip

Sudden longitudinal traction on the pronated forearm.

Example: pulling a child up by the hand, swinging them by the arms, or when child is yanked to prevent a fall.

mechanism of a radial head subluxation

Radial head subluxation (nursemaid's elbow)

Child suddenly refuses to use arm.

Arm held slightly flexed and pronated against the body.

Minimal crying once initial pain subsides.

-arm in pronation + slight flexion

-elbow appears normal

Child avoids moving arm but often distractible (suggesting pain is not constant).

Distinguishing point: no ecchymosis or obvious deformity, which helps rule out fracture

physical exam findings associated with nursemaids elbow

Supination-flexion technique (most common, ~80–90% success):

Support elbow, supinate forearm, then flex elbow fully.

A “click” or “pop” may be felt over radial head.

describe the most common reduction maneuver of nursemaids elbow

-much of skeleton cartilaginous at birth

-secondary ossification centers (epiphyses) appear in predictable stages

describe the process of skeletal maturation

physes (growth plates)

Located between epiphysis and metaphysis.

Composed of cartilage → responsible for longitudinal bone growth.

apophyses

Secondary ossification centers at tendon/ligament attachment sites (e.g., tibial tubercle, calcaneus).

Common sites of overuse injury in growing athletes

Pediatric bones are more porous, pliable, and less mineralized compared to adults.

Periosteum is thicker and more vascular, allowing faster healing.

how are pediatric bones different from adult bones

Salter-Harris fracture

example of growth plate (physeal) injury

Osgood-Schlatter disease (tibial tubercle)

Sever's disease (calcaneal apophysis)

Little League elbow/shoulder (medial epicondyle, proximal humerus)

example of apophyseal injuries

greenstick fracture

unique pediatric fx pattern due to incomplete cortical break due to pliable bone

metaphysis

growth zone between the epiphysis and the diaphysis during development of a long bone

Type I Salter-Harris Fracture

separation through the physis, usually through areas of hypertrophic and degenerating cartilage cell columns

Type II Salter-Harris Fracture

Fracture through a portion of growth plate and metaphysis.

Type III Salter-Harris Fracture

fracture through a portion of the physis that extends through the epiphysis andd into the joint

Type IV Salter-Harris Fracture

fracture across the metapysis, physis and epiphysis

type V salter harris fracture

crush injury to the physis

Buckle (torus) fracture

Compression injury of the bone cortex, usually at the metaphysis, without complete cortical disruption.

Clinical: Mild pain, localized tenderness; stable fracture.

X-ray: Subtle bulging or buckling of cortex.

Management: Splinting or short-term immobilization; heals quickly (2–3 weeks).

Axial loading (fall onto outstretched hand).

mechanism of a buckle fracture

greenstick fracture

Definition: Incomplete fracture where one cortex breaks and the opposite cortex bends.

Mechanism: Bending forces (fall onto outstretched arm).

Clinical: Pain, deformity possible.

X-ray: One side disrupted, the other intact but bowed.

Management: Reduction if angulated, then casting. Bone remodeling potential is high in kids.

complete fracture

Definition: Break extends through both cortices of the bone.

Mechanism: Higher-energy trauma compared to buckle/greenstick.

Clinical: Pain, swelling, deformity, possible neurovascular compromise.

bowing (plastic deformation) fracture

Definition: Bone bends beyond its elastic limit without a visible fracture line.

Mechanism: Longitudinal stress or low-energy trauma (fall, twisting injury).

Clinical: Persistent pain, deformity, limited use of extremity.

X-ray: No fracture line, but visible curvature of bone compared to the contralateral side.

Buckle + greenstick + bowing =

fractures that are unique to children

open growth plates (physes)

These cartilaginous areas are weaker than ligaments or tendons → more prone to injury.

Sever's Disease (Calcaneal Apophysitis)

Inflammation of the calcaneal growth plate that occurs during adolescence. Rapid growth increases tension in the achilles tendon, which places a shearing force on the growth plate. Heel pain is aggravated by activities such as running & jumping.

>10 degrees

Cobb angle indicating scoliosis

brace treatment

in 3-9 y/o, what is tx for cobb angle 25-45 degrees

radiographs every 6-12 months until curve progression or maturity

in 3-9 y/o what is the management for cobb angles between 10 and 20?

surgery with magnetically controlled rods

in 3-9 y/os what is the management for cobb angle greater than or equal to 45?

scoliosis surgery

in 10-18 y/os how do you manage cobb anglle over 45

kyphosis

exaggerated forward rounding of the upper back

Legg-Calvé-Perthes disease (LCPD)

-idiopathic avascular necrosis of the capital epiphysis of femoral head

-gradual onset, limpp often more prominent at end of day

-painless limp; may become hip or groin pain

clinical presentation of legg-calve-perthes disease

Legg-Calve-Perthes Disease

thomas test shows inability to fully extend hip=hip flexor contraction

+ galeazzi sign

4-8 y/o

most common age of LCPD

Crescent sign

Xray sig of LCPD

-subchondral lucency from bone resporption

-close observation by ortho

-activity limitation, NSAIDds

-severe cases may need surgery

management of LCPD

Osgood-Schlatter disease

painful enlargement of tibial tuberosity at patellar tendon insertion

-a traction apophysitis due to excesesive tension (pulling) on site

-seen in very physically active boys 10-15 yo

cause of osgood-schlaltter disease

Osgood-Schlatter disease

diagnosis can be made clinically but xray would show fragmentatiion off tibial tubercle

reassurance, rest, NSAIDs

tx of osgood-schlatter

sever's disease

activity related heel pain in 8-13 yo

-calcaneal apophysitis at insertion of achilles to calcaneus

hyperpronation off the foot and tight achilles tendon

mechanism of sever's injury

avoid overuse, orthotics

mgmt of sever's injury

SCFE

slipping of femoral head off of femoral neck

-limited IR off hip

-shortenedd legg that is externally rotatedd

PE findings associatedd with SCFE

more common in AA and hispanic populations

-obese male, 10-16 yo

pt population of SCFE

widening of physis without slippagge

earliest XR sign of SCFE

Torticollis

Unilateral shortening of the SCM muscle of the neck

Causes child to bend their neck to the same side and rotate to the opposite side

tilted head towards shoulder typically with pain on tilted side

signs and symptoms of torticollis

-spasmodic most common due to genetics

-birth injury leading to fibroma or hematoma

-iatrogenic

causes of torticolllis

stretching, botox, surgery

tx of torticollis

afebrile, walk with limp

-commonly seen after URTI or other viral illness

presentation of transient synovitis

benign self limited

-effusion seen on XR/US

-joint aspiration negagtive, labs normal

prognosis of transient synovitis

NSAIDs, supportive

tx of transient synovitis

septic artritis

-acute onset of ffever and joint pain

-limited ROM of joint with significant pain

-ill appearing

Staph and H. flu

most common bacteria of septic joint

IV abx and surgical drainage

tx of septic joint

hypotonia

decreased resistance to passive movement

Cerebral palsy (esp. early phase)

Genetic syndromes: Down, Prader-Willi, Angelman

Brain malformations, hypoxic-ischemic encephalopathy

Metabolic disorders (urea cycle, mitochondrial diseases)

CNS causes of hypotonia

Spinal cord: Spinal muscular atrophy (SMA)

Nerve: Peripheral neuropathies, congenital hypomyelination

Neuromuscular junction: Botulism, congenital myasthenia

Muscle: Congenital muscular dystrophy, congenital myopathy, metabolic myopathies

peripheral causes of hypotonia

hypotonia + hyperreflelxia= central cause

hypotonia + hyporeflexia= peripheral cause

identifying cause of hypotonia as central or peripheral