Lower Extremity Problems in Children

Part 1

AAP Board Content Specifications:

  • Recognize the clinical findings associated with various valgus & varus deformities, understand when referral is appropriate
  • Understand the natural history of femoral anteversion & plan the appropriate clinical & diagnostic evaluation
  • Recognize the clinical findings associated with tibial torsion
  • Recognize the clinical findings associated with clubfoot & the need for prompt referral

Board PIR questions: (There are no PREP questions on these topics)

  1. You are seeing a child born at home for the first time at this 2-week health supervision visit. The mother’s primary concern is the shape of her son’s foot. The best maneuver to perform to differentiate metatarsus adductus from clubfoot is to:
  2. Abduct the forefoot
  3. Compare the appearance of the feet
  4. Dorsiflex the ankle
  5. Look for transverse crease on the plantar surface
  6. Tickle along the lateral aspect of the foot
  7. A 5 y/o girl continues to “intoe” although this has no impact on her level of activity or function and is otherwise healthy. The most likely cause for this condition is:
  8. Femoral anteversion
  9. Malignant Malalignment syndrome
  10. Metatarsus adductus
  11. Talipes equinovarus
  12. Tibial Torsion
  13. A 3 y/o girl is “bowlegged” and because her mother is certain that it is getting worse she requests an immediate radiograph. The finding that would BEST support the parent’s request is:
  14. A “bowlegged” appearance at birth
  15. A normal sequence of achieving motor milestones
  16. A symmetric appearance to the lower extremities
  17. The absence of pain in the lower extremities
  18. The natural history of angular deformities in the lower extremities
  19. Which of the following is a characteristic of metatarsus adductus?
  20. Hindfoot equinus deformity
  21. Hindfoot varus deformity
  22. Hindfoot valgus deformity
  23. Lateral deviation of the forefoot
  24. Medial crease of the instep
  25. A 7 y/o girl is brought to your clinic for in-toeing that has persisted since she was 3 y/o. She frequently sits in a “W” pattern on the floor while watching TV. Physical Examination reveals markedly increased internal rotation of the hips while prone. Which of the following statements regarding this girl’s condition is true?
  26. CT scan is indicated to confirm the diagnosis
  27. She is at high risk for developing osteoarthritis of the hips later in life
  28. She likely will be able to participate in sports without difficulty
  29. She should begin wearing medial pads in her shoes to correct the in-toeing
  30. The in-toeing likely is due to a dietary deficiency
  31. You are evaluating an 18 m/o boy whose mother thinks he is “pigeon-toed.” He began walking at 12 months and walks well, but in-toeing is noted on examination. Range of motion at the hips, knees, and ankles is normal. Which of the following is the MOST likely cause of his gait disturbance?
  32. Blount disease
  33. Femoral anteversion
  34. Internal tibial torsion
  35. Metatarsus adductus
  36. Pes Planus

Rotational deformities:

Intoeing & Outtoeing are the most common musculoskeletal entities that bring parents into your office. History & physical exam findings are usually sufficient to make are accurate diagnosis & imaging is usually not necessary.

Intoeing: has 3 different points of origin- foot, between knee & ankle, between knee & hip

Metatarsus adductus: most common congenital foot deformity

  • Incidence: 1/1000 – 1/1500 live births
  • Epi: 50-60% bilateral, increased risk if + family history, L>R
  • Diagnosis: packing defect in which the forefoot is angled toward the midline of the body (bean shaped foot)- medial deviation of forefoot relative to hindfoot (normal position)
  • No hindfoot varus or equinus deformity of foot or ankle
  • Deep medial crease generally present
  • Differential: Clubfoot, skewfoot
  • Classification of severity:
  • Heel Bisector: Degree can be quantified grossly by bisecting the heel up to the forefoot. Normally, a heel bisector should hit between the 2nd& 3rd rays of the foot.
  1. Can also be classified in terms of flexibility:
  2. Correctible: if baby straightens the foot in response to be tickled along its lateral border
  3. Passively correctible: if it does not correct with ticking, but does with gentle lateral pressure on 1st metatarsal head.
  4. Rigid: does not correct with stretching.
  • Imaging: not indicated
  • Treatment:
  • Correctible- follow heel bisector, corrects spontaneously
  • Passively correctible- stretching exercises (5x/foot holding correction x 10 seconds with each diaper change)
  • Studies show that most infants correct with manipulation by 4-6 months of age
  • No more than 15% of children require additional treatment (reverse last shoes, casting, surgery)
  • Rigid- stretch casting or wheaton brace

Internal Tibial torsion: packaging defect, most commonly seen in children <3. Although present at birth, most often not noticed by parents until the child begins to stand or walk.

  • Epi: left > right but frequently bilateral
  • Risk factors: family history, bowleggedness (infantile tibial vara) especially if early walkers (8-9 m/o)
  • Diagnosis: Prone position
  • Thigh foot angle: normal = 10-15 degrees external relative to long axis of the thigh

A= external tibial torsion (>20 degrees), B = normal, C = internal tibial torsion

  • Medially deviated foot when patella is facing directly forward
  • Prognosis: Improves with the first year of ambulation
  • Spontaneous resolution by 5-6 y/o
  • Imaging: usually not necessary
  • Treatment: Treatment is rarely necessary, reassurance
  • Surgery involving derotational tibial osteotomy may be needed in patients >6 if significant deformity from either internal or external tibial torsion affects function or gait

Femoral Anteversion (Medial Femoral Torsion): most common cause of intoeing in children >3 y/o

  • Pathogenesis: Normally born with anteversion (40 degrees), which improves 1.5-2 degrees/year from birth to 12 y/o to the adult norm (10 degrees).
  • In MFT, the version angles increase to 60 degrees between 4-6 years
  • Physical Exam:
  • Typically sit in the W position
  • Prone exam testing of hip rotation:
  • Internal rotation: increased rotation beyond 60-65 degrees
  • External rotation: decreased in external hip rotation

  • Normal rotation progression by age:

  • Imaging: usually not necessary
  • Prognosis: Typically resolves without intervention, typically correcting slowly between 8-12 years old
  • “Recent studies suggest intoeing may be beneficial in certain activities and sports, therefore parents should be reassured that increased femoral anteversion should not compromise athletic performance5”
  • Treatment:
  • Spontaneous resolution in most
  • Surgery: Persistent severe anteversion associated with intoeing that causes functional impairment may be treated with femoral derotational osteotomy
  • Do NOT recommend: bracing, twister cables, shoe modifications as these are ineffective & not recommended

Outtoeing: Less common than intoeing, usually a packaging defect

Calcaneovalgus deformity (Talipes Calcaneovalgus):packaging defect

  • Epi: Associated with external tibial torsion
  • Diagnosis:
  • The ankle is dorsiflexed, abduction of forefoot, & heel is turned outward
  • Often results in forefoot resting on the anterior surface of lower leg
  • Good flexibility of hindfoot & forefoot as well as with good ankle range of motion
  • Differential: Rocker bottom feet (Congential vertical talus)- unable to correct with gentle pressure, paralytic calcaneous foot deformity
  • Treatment: recommend stretching

External Tibial Torsion: most common cause of outtoeing in infants & young children

  • Diagnosis: Perform rotational profile- diagnostic & charts progress
  • Watch the child walk to determine the foot progression angle
  • Intoeing = negative, Outtoeing = positive
  • Most adults = +10

  • Prone position testing:
  1. Heel bisector
  2. Thigh-foot angle (line down the center of thigh)- angle this line forms with heel bisector is the thigh-foot angle (should be 0-10 degrees)
  3. Usually 30-50 degrees with external tibial torsion
  4. Degree of internal & external rotation are measured (should be 45 degrees +/- 20) in both directions
  • Prognosis: most correct spontaneously
  • Most improve within 1st year of walking
  • Disability as in patellofemoral instability is more common in children with persistent external tibial torsion than in persistent internal tibial torsion
  • External tibial torsion is more likely to persist through adolescence than internal tibial torsion
  • Treatment: none necessary, follow measurements above
  • Do NOT recommend bracing, shoe modifications as these are ineffective & not recommended
  • Surgical treatment is rarely indicated & reserved for older child with marked function or cosmetic deformity (thigh-foot >+40 degrees)

Angular deformities:

A common musculoskeletal variation encountered by Pediatricians. A child with “Bowlegs” or “Knock knees” commonly prompts parents to bring their child to the doctor, often requesting intervention or referral. However, PCP‘s can monitor most patients with these variants. History & physical exam findings are usually sufficient to make are accurate diagnosis & imaging is usually not necessary.

Genu Varum (“bowleg”)

  • Epi: associated with internal tibial torsion
  • Normal Progression:
  • All babies born bowlegged, but often parents don’t notice this until they are pulling to stand
  • Between 18 months-2 y/o it starts to decrease to neutral
  • Features of physiologic Varum:
  • Birth-2 yrs
  • Bilateral & relatively symmetric
  • Bowing of both femurs & tibias
  • Normal stature
  • No lateral thrust with ambulation
  • Examination:
  • Check length/height, weight (overweight associated with blount)
  • Follow clinical progression every 6 months: distance between knees with angles together
  • Greater than 6cm between femoral condyles is considered abnormal at any age
  • Assessment of leg length
  • Assessment of gait- note foot/patellar progression, check for brief lateral knee joint protrusion that suggests incompetence of knee ligaments
  • Imaging: Not needed in children <3 y/o following the normal progression with normal examination & history
  • Differential: Pathological causes (severe, unilateral, abnormal progression –persistence to 3 y/o, short stature, lateral thrust)
  • Blount disease: disruption of normal cartilage at medial aspect of proximal tibial physis  severe varus deformity, leg length discrepancy
  • Rickets (onset before 2 yrs, associated with short stature)
  • Skeletal dysplasia (short stature & characteristic physical features)
  • Asymmetric growth after trauma, infection, or tumor
  • Prognosis/Treatment: Follow clinical progression every 6 months
  • Spontaneous resolution in most
  • Persistent varum beyond the expected period can cause damage to medial aspect of the knee joint & pain later in life
  • Orthotics- braces, splints, shoe inserts are ineffective & unnecessary
  • Imaging and/or referral to surgeon or other specialist based on suspected underlying pathological causes
  • Surgery is reserved for patients with residual deformity after medical optimization

Genu Valgum (“Knock-knees”)

  • Epi: Associated with pes planus & external tibial torsion
  • Natural Progression:
  • Child usually maximally “knock-kneed” (Valgus) by 3-4 y/o (sometimes 5 y/o)
  • After 3-5 y/o valgus should decrease& by 7 y/o most children have reached the adult configuration, slightly knock-kneed (valgus) to neutral
  • Features of physiologic valgus:
  • Aged 2-5 y/o
  • Symmetric valgus deformity
  • Normal stature
  • Lack of symptoms (severe cases may be knee pain or difficulty running)
  • Lack of medial thrust with ambulation
  • Examination:
  • Check length/height, weight (overweight associated with idiopathic genu valgum)
  • Follow clinical progression every 6 months: distance between ankles with knees together
  • Distance of >8cm between intermalleolar structures is pathologic at any age
  • Assessment of leg length
  • Assessment of gait- note foot/patellar progression, check for brief medial knee joint protrusion that suggests incompetence of knee ligaments
  • Imaging:Not needed in children <5 y/o following the normal progression with normal examination & history
  • Differential: Pathological causes (severe, unilateral, abnormal progression >5 y/o, age <2 or >7 y/o, short stature, medial thrust)
  • Rickets (onset >2 y/o)
  • Trauma (Cozen fracture)
  • Skeletal dysplasia
  • Neoplasms (multiple hereditary exostoses)
  • Metabolic diseases
  • Prognosis/Treatment:Follow clinical progression every 6 months
  • Spontaneous resolution in most, if not at adult norm by 10 y/o refer
  • Braces are ineffective & unnecessary
  • Pathologic/persistent valgus can affect knee function  abnormal tracking of patella, increased stress on MCL, patellofemoral pain or subluxation, increased risk of osteoarthritis
  • Imaging and/or referral to surgeon or other specialist based on suspected underlying pathological causes
  • Surgery is reserved for patients >10 y/o with residual deformity after medical optimization, symptoms (difficulty running or persistent pain), severe deformities

Foot deformities:

Metatarsus Adductus (see above)

Calcaneovalgus deformity (see above)

Clubfoot (Congential Talipes Equinovarus):

  • Incidence: 1/1000 live births
  • Epi: Bilateral in 50%, male predominance 2:1
  • Pathogenesis: unknown, thought to be secondary to genetic, neurologic, muscular, and intrauterine compression influences
  • 4 Components of Physical Exam:
  1. Equinus positioning (inability to dorsiflex at ankle)
  2. Cavus positioning (high longitudinal arch)
  3. Metarsus adductus
  4. Hindfoot varus

Acronym: CAVE = cavus, adductus, varus, equinus

Smith B G Pediatrics in Review 2009;30:287-294

  • Differential: Metatarsus Adductus, Rocker bottom foot (trisomy 13), calcaneovalgus
  • Metatarsus Adductus: Clubfoot is resistant to passive correction of fixed hindfoot, whereas Metatarsus adductus is not
  • Calcenovalgus: opposite of metatarsus adductus
  • Imaging: usually not necessary
  • Treatment:
  • Early referral to Ortho- within first few weeks of birth
  • Serial casting- corrects forefoot adduction, hindfoot varus deformity
  • Tendo-achilles lengthening
  • Bracing (Denis-Browne bar) & straight last shoes

Flatfoot (Pes Planus):

  • Pathogenesis:
  • Typical position of children’s feet until 6y/o secondary to ligamentous laxity
  • Usually between 6-8 y/o the medial arch maintains elevation on standing in most children
  • Flexible flatfoot is considered a normal variant in growing children
  • Diagnosis: key is to determine flexibility
  • Medial longitudinal arch collapse during standing can be restored by:
  • Recumbency or sitting
  • Elevates with toe standing or
  • Elevates with passive elevation of great toe
  • Assess the presence of hind foot valgus (lateral position of the heel)
  • Toe standing causes medial deviation of the heel in normal feet  both the flat arch & heel position are flexible
  • Hindfoot that does not invert with toe standing may indicate another disorder: peroneal spasm, tarsal coalition, inflammatory arthritis of subtalar joint
  • Assess heel cord excursion & ankle dorsiflexion
  • Heel cord tightness may be reasons for hind foot valgus  painful flatfoot that should be evaluated
  • Treatment:
  • Arch support does not influence nor promote development of the arch
  • < 8y/o: no treatment indicated, reassurance
  • Teenagers:
  • Tight heel cord: heel cord stretching program possibly directed by PT
  • Othotics may be beneficial
  • Referral to Orthopedist if pain persists despite above measures

PIR Answers:

  1. C
  2. A
  3. E
  4. D
  5. C
  6. C

References:

  1. McKee-Garrett, TM. Lower extremity positional deformations. In: UpToDate, Weisman, LE (ed), UpToDate, Waltham, MA, 2013.
  2. Rosenfeld, SB. Approach to child with bow-legs. In: UpToDate, Phillips, W (ed), UpToDate, Waltham, MA, 2013.
  3. Rosenfeld, SB. Approach to child with Knock-knees. In: UpToDate, Phillips, W (ed), UpToDate, Waltham, MA, 2013.
  4. Scherl, SA. Common Lower Extremity Problems in Children. Pediatrics in Review. 2004; 25 (2): 52-62.
  5. Smith, BG. Lower Extremity Disorders in Children and Adolescents. Pediatrics in Review. 2009: 30 (8): 287-294

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