Lower Extremity Anatomy and Biomechanics

• Podopedics is the study and treatment of the foot and ankle, especially in children.

Lecture 1 & 2: Ground Rules and Introduction

• Key terms are divided into age ranges, including newborn (birth to 1 week), infant (1 week to 1 year), toddler (1-3 years), early childhood (1-5 years), late childhood (6-12 years), and adolescent (12-18 years).
• A newborn's hip position is typically flexed, abducted, and outwardly rotated.
• STJ ROM (subtalar joint range of motion) in a newborn is approximately 45 degrees.
• Range of ankle dorsiflexion in a newborn is about 75 degrees, while plantarflexion is around 60 degrees.
• Metatarsus adductus involves a transverse plane deformity where the metatarsals are directed inward.
• Post-casting maintenance for corrected metatarsus adductus includes using a straight last shoe with pads.
• Postural deformity (PD) refers to the deformation of a normally formed part due to the fetus being confined in an unnatural position in the uterus.
• PD is more common on the baby's left side because it's often in contact with the mother's spine.

Serial Casting and Clubfoot

• Serial casting is utilized for congenital deformities.
• Plaster casts are applied to the foot in a corrected position, then soaked and removed in 1-2 weeks, and the process is repeated.
• Talipes equinovarus (clubfoot) presents with a "down and in" appearance.
• Clubfoot is treated with a series of above-knee plaster casts, with approximately 90% of cases requiring surgical intervention.
• Post-op bracing protocol involves full-time bracing for 3 months, followed by nighttime bracing for 2-4 years.
• Intoe gait is commonly caused by internal tibial torsion in the first 3 years of life.
• Treatment options include the Dobbs brace, Denis Browne bar, ballet, pelvic band, and strap.
• Genu valgum (knock knees) occurs when knees touch but ankles do not.
• Genu varum (bow leg) is when ankles touch but knees do not.

Normal Development Ranges and Dermatitis

• Normal Genu varum development ranges from birth to 1.5 years, straight alignment from 1.5 to 3 years, Genu valgum from 3-6 years, and straight alignment from 6-12 years.
• Atopic dermatitis (eczema) presents on anterior surfaces in infants and flexor regions in older individuals.
• HPI (History of Present Illness) uses NLDOCAT to gather specific details: Nature, Location, Duration, Onset, Course, Aggravating factors, Treatment
• The APGAR test is conducted after 1 minute to assess how a baby tolerates birth and again after 5 minutes to see how the baby is doing outside the mother's body.
• An abnormal APGAR score is less than 7.
• APGAR is graded out of 2 as normal
  • Appearance: 0 = blue; 1 = pink trunk, blue limbs; 2 = pink
  • Pulse: 0 = no heartbeat; 1 = HR < 100; 2 = HR > 100
  • Grimace: 0 = no response; 1 = grimace; 2 = grimace w/ sneeze, cough or cry
  • Activity: 0 = floppy; 1 = some muscle tone; 2 = active motion
  • Respiration: 0 = shallow; 1 = irregular; 2 = normal

Developmental Milestones

• Delay in developmental milestones can suggest an underlying neurologic disease.
• Movement milestones:
  • 2 months: lifting head in a prone position briefly
  • 4 months: rolling from front to back
  • 6 months: rolling both ways
  • 7 months: sitting independently
  • 10 months: reciprocally crawling
  • 10-15 months: walking
  • 2 years: running without falling, going up and downstairs unassisted
  • 2.5 years: jumping
  • 3 years: going up and downstairs alternating feet
  • 5 years: hopping on 1 foot, walking in a straight line
• Speech development:
  • 12 months: using one word other than "mama" or "dada"
  • 15-18 months: speaking 6 words
  • 21-24 months: using 2-3 word phrases
  • 2 years: using approximately 270 words with pronouns
  • 3 years: using around 900 words.

Screening and Arteries

• The Denver developmental screening test detects developmental delays in children up to 6 years old, primarily used for birth to 2-year-olds.
• Significant failure on the Denver test includes failing to perform a task that 90% of similar-aged children can do or failing 2 tasks, indicating a developmental delay.
• Landmarks for locating arteries:
  • Dorsalis pedis (DP) artery: lateral to the extensor hallucis longus (EHL) tendon.
  • Posterior tibial (PT) artery: posterior to the medial malleolus.
• It can be difficult to obtain DP or PT pulses in infants.
• A femoral pulse is the next best option.
• A dermal dimple in the lumbosacral area can indicate a spinal cord tumor.

Reflexes

• Primitive reflexes are present at birth and decrease over 4-6 months after birth.
• Primitive reflexes include:
  • Sucking reflex.
  • Moro reflex: holding the baby supine, then drop the head a few inches, triggering arm extension and midline return.
  • Galant reflex: stroking the paravertebral muscle causes the spine to curve toward the stimulus. Stepping/walking reflex: holding the baby upright with soles touching a surface causes leg flexion and extension.
  • Palmar and plantar grasp reflex.
  • Asymmetrical tonic neck reflex (Fencer's lunge): head-turning produces ipsilateral arm/leg extension and contralateral flexion.
• Postural reflexes develop between 3-8 months.
• Postural reflexes include:
  • Landau reflex (4-5 months): head extension above the trunk plane triggers leg extension.
  • Lateral propping (5-7 months): arm extension prevents falling. Parachute reflex (8-9 months): quick supine placement causes arms to extend forward for protection.
• Persistence of primitive reflexes and a lack of postural reflexes development suggests upper motor neuron (UMN) disorders.

Neurological Exams and Hip Rotation

• In a newborn neurological exam:
  • Doll's eye: eyes move in the opposite direction of head movement. When in the prone position, the baby should be able to lift their head and move their arms from side to side and forward.
  • Arm/leg recoil: extended limbs quickly return to a flexed position.
• Scarf sign: hand to the opposite shoulder shouldn't go past the shoulder, and the elbow shouldn't pass the midline.
• Popliteal angle: flexing the thigh while extending the knee shouldn't exceed 90 degrees.
• Traction response: moving an infant from supine to sitting, some head lag should occur.
• Head control: when sitting with the head on the chest, the baby should be able to raise their head into an upright position
• Ventral suspension: the baby is held in a prone position with a hand under the baby’s chest, and the head should be level with the back
• Vertical suspension: baby held under their axillae and the body should not slip through the hand
• Deep tendon reflexes are brisk with few beats of clonus in the first few weeks of life.
• A positive Babinski sign typically indicates a UMN lesion, except in babies younger than 1 year old.
• Bleck's test measures metatarsus adductus using a ruler from the plantar heel through the forefoot.
  • Normal: bisects the 2nd toe/interspace.
  • Metatarsus adductus: more lateral bisection of the toes.
• Dorsiflexion ROM of the 1st MTPJ: off weight-bearing (65 degrees), weight-bearing (15-20 degrees).

Measurements

• Measuring STJ ROM involves heel position during supination.
• Measuring ankle ROM involves STJ position during supination.
• Excessive dorsiflexion with an STJ in pronation gives a false reading.
• A flexed knee should lead to consideration of equinus when:
  • Dorsiflexion is < 90°.
  • Equinus = limited dorsiflexion.
• Unequal leg length indicates checking for scoliosis via the Adams forward bend test if the pelvis is not level.

Hip Rotation and Flexors

• Normal hip rotation ranges:
  • Infants: lateral (60°), medial (0-30°).
  • 6 months: lateral (50°), medial (30°).
  • 1-4 years old: lateral (40-45°), medial (30-35°).
• Femoral rotation is observed in the prone position:
  • Medial rotation causes legs to flop outward.
  • Lateral rotation causes legs to flop inward (cross midline).
• Hip flexor assessment: pull both knees to the chest while extending one leg to see if the posterior thigh touches the table, indicating good ROM.
• 70°of hip flexion is obtained with an extended knee, if testing for hamstring flexibility.
• Popliteal angle is measured by flexing the hip to 90°, extending the knee until resistance, and measuring from the axis of the lateral thigh to the axis of the lateral tibia to determine hamstring flexibility.
• Normal popliteal angle:
  • Birth - 2 years: 0-6°.
  • Over 5 years: 0-25°.

Hip Abduction and Torsion

• Barlow and Ortolani tests are used for up to 3 months of age:
  • Barlow: attempt to dislocate the hip.
  • Ortolani: reduces a hip that is already dislocated.
• Degrees of hip abduction:
  • Newborn: 80-90°.
  • 2-9 months: 70°.
  • 2-4 years: 50°.
• The Trendelenburg sign indicates contralateral side of the dislocated hip dips during gait, due to abductors being weak on the dislocated side.
• Tibial torsion values:
  • Birth: 0°.
  • 18 months: 9°.
  • 3 years: 12°.
  • 6 years: 18-23°.
• Internal torsion is less than normal.
• External torsion is greater than normal.
• Normal thigh-foot angle based on tibial torsion: foot lateral to the posterior thigh.
• Internal torsion makes the foot medial to the posterior thigh.

Torsion Appearance and Forefoot

• Tibial torsion vs. femoral torsion is assessed by looking at the appearance of the knees:
• Inward appearance indicates femoral torsion.
• The relationship between STJ supination and pronation: supination to pronation ratio is 2:1 or possibly 3 or 4:1 in children.
• Forefoot frontal plane:
  • Pes planus is varus.
  • Pes cavus is valgus.
• Lumbar lordosis indicates laxity and can be assessed using the Beighton scale, with a score ≥ 4 out of 9 indicating laxity.

Feet Alignment

• The met planes should be perpendicular to the heel bisection in the forefoot-to-rearfoot relationship
• The relationship should be checked while manually dorsiflexing the 4th and 5th metatarsal heads.
• The secondary axis should be perpendicular to the ground, as compared to the heel bisection in a relaxed and neutral calcaneal stance position.
• Midtarsal joint subluxation on weight-bearing involves the forefoot being abducted to the rearfoot.
• Lower malleolar height indicates more pronation.

Lecture 3-5: Radiology and Congenital Deformities

• Primary ossification center:
  • it's the first area of bone to start ossifying.
  • Usually happening prenatally.
• The secondary ossification center appears postnatally and extends through adolescence.
• Accessory bones commonly represent skeletal variations:
  • Usually stemming from the failure of secondary growth centers to fuse with the main bone.

Accessory Bones

Common accessory bones:

• Os Vesalium
• Accessory bone of the 5th metatarsal base
• Os Trigonum
  • differentiated from fractures by dorsiflexing the hallux.
• Os Peroneum
• Os Supranaviculare
• Accessory navicular
  • Type 1
  • Type 2
  • Type 3
• Radiographic anatomy includes:
• Diaphysis
• Metaphysis
• Growth plate (physis)
• Epiphysis
• Epiphysis associated with joint
• Appophysis is not Radiographic views include:
  • DP view
  • Lateral view
  • Medial oblique view
  • Lateral oblique view
  • Harris Beath view (ski jump)

Radiographic View Analysis

• DP view assessment:
  • Talocalcaneal angle (Kite's angle):
    • a wide angle indicates a pronated foot.
    • a narrow angle indicates a supinated foot.
  • Talus-First met angle: measures the relationship of the rearfoot to the forefoot.
• Lateral view assessment:
  • Calcaneal apophysis
    • posterior ossifying between 6-10 years and fusing at 17 years.
    • Can have a fragmented appearance.
  • Lateral talocalcaneal angle shows that
    • Increased angle indicates a pronated foot
    • Decreased angle is a supinated foot
  • Calcaneal inclination angle.
    • Lower inclination indicated a pronated foot
    • More inclination is supinated foot
• Talar declination (horizontal) angle
  • Increased angle is a prontated foot
  • Decreased angle is a supinated foot
• Medial oblique view: used for Calcaneonavicular coalition (CN Bar)
• Lateral oblique view: used for Navicular pathology (accessory, fracture)
• Harris Beath view (ski jump): Talar & calcaneal coalition

Bones and Osification

• Bones visible on X-ray at birth: talus, calcaneus, cuboid, metatarsals, & phalanges.
• Ossification:
  • Navicular: 2-4 years
  • Cuneiform:
    • Medial: 6 months - 2 years
    • Middle: 1-4 years
    • Lateral: up to 12 months
  • Cuneiform:
    • Phalanges & metatarsals secondary centers: 6-24 months.
    • 5th metatarsals base: 9-14 years.
• Ossification center locations in DP view:
  • Distal 2nd-4th mets
  • 5th met = distal (epiphysis) + proximal (apophysis)
• Hallux sesamoids in females is between 8-12 years/ Male is from 10-14 years
• All secondary ossification centers fused by an age of 22

Foot Variants on X-ray

• Claw toes when x-ray taken means pseudocavus is present
• Pseudocyst of calcaneus
• bifid calcaneus
• Split epiphysis
• Bell or cone-shaped epiphysis

Unicameral Bone Cyst and Normal Feet

• Unicameral bone cyst: The fluid-filled lesion often in the calcaneus has a thick overlying cortex
• Features of a normal foot (DP view):
  • Talocalcaneal angle: is between 30-50° at birth and from 15-35° in 5-6 years old
  • Calcaneal bisection relative to the forefoot at birth bisects 4th met and from 5-6 years old bisects between 3 -4th
  • Talar-First metatarsal angle (talar bisection) is medial to the 1st met at birth, is normal from 0 to -20°, and at around 5-6 years the bisection should bisect the 1st metatarsal
• Features of a normal foot (Lateral view):
  • Talar declination angle is up to 35 ° at 3years and 25° at 8 years old
  • Calcaneal inclination angle is 10-15 ° at birth and 15-25° at 5-6 years.

More on Flat Feet and fractures

• In a frontal-plane-dominant 5 flat foot is when, on lateral view, the lateral calcaneal line runs parallel to the cuboid and longitudinal sag at the TN joint.
• Subungual osteochondroma is more common as a bone tumor with a cartilaginous cap.
• Salter-Harris Fracture is an epiphyseal plate fracture in children -Commonly occurs in the angle and slows growth -The only sign on X-ray is distinct local tenderness.
• Epiphyseal injuries of the foot grows really slowly after the age of 5
• Most often involves the distal metatarsal and the proximal phalanges
• Drop of had objects or stub toe

Congential Deformities

• Non-teratologic deformity that is a deformation of normally formed parts from intrauterine positioning = Postural Deformities
• It is correctable w/ passive manipulation
• Types:
  • Calcaneovalgus- a “up and out “ deformity with alow arch
  • Valgus heel and forefoot varies is usually congenital
  • The talis is planterflexes -More common in females

Equinovarus Analysis

• Rocker-bottom deformity (planter convexity) + rigid flat foot due to a TN dislocation are Convex pes cavus
• In convex and Calcaneovalgus the TC angle is more than 40 ’ degrees.
• Two structures that are not tightened are:
  • Spring ligament
  • Planter medial TN joint capsule
• Convex pes valgus and Dorsal is on the lateral Stress planterflexion is for correctable talus

Postures

• Posterior talips equinovarus (clubfoot) is a down and in pathology
• “CAVE”
  • Cavus
  • Adduction (forefoot) -Varus (rearfoot) -Equinus
• DP and lateral views are used to analyze “cave Simon’s rule is used on DP view to assess/ analyze- Talar-st Talocalcaneal angle<20

Flexion and Adduction

• Talar first met angle > 15 degrees
• TC angle < 15
• Lateral view shows: -talocalcaneal angle is less than 25 degrees -Parallelism or closed to the parallelism of tales and calcaneous -It is normal for the 1st metatarsal to be superior Two classifications of tales equinovarus : -Pinan -Dimeglio There is gentle correct with tales quinovarus

Talipes Equinovarus Treatments

• Talipes Equinovarus can be treated with:
• French (functional) method, the first treatment : daily stretch and manipulation by the patient, stretch with augemented tape.
• Ponseti technique is a gold standard treatment used today where minimal surgery is followed by 5-8 weeks of above-knee catting treat TEV The order of deformity correction is
• Carvus - abduction with valgus - Equinus
• 2months of bracing all the time
• The most flexible night brace is the Dobb’s brace
• Transverse plane of deformity as the tarsometatarsal or joint (11sfranc)

Forefoot borders and Torsion

• Transverse plane of deformity happens at the tarsometatarsal joint or Lifranc in Metatarsus addutus
• • Shaped foot is concave medical and convex Lateral border
• Do not treat before 4 months old, normal physologic correction
• Splaying of the 1st intermatatarsal space due to more adducted 1st met happens as a form of Internal tibial torsion
• Normal angle is 20° - 35° from birth to 4months
• Treatment includes serial casting, semi-rigid fiberglass brae for MA not created within e optimal window from about 4 to 9 monthss with Extension contracture of knee. -ROM = TEV and MA
  • Congenital Malformation: -not correctable with pasice manip

Cavus Type

• Rate of deformity is characterized by rear foot vagus, midfoot abduction, forefoot adduction for Skew foot

• Absence of 2-4 rays and presents of 1st and 5th ray means Ectrodavityly exist.

• Abnormally shortening of matatarsal by more than 5mm means premature physis closing exist.

• Excessive numbers of digits means polydactyl

• Complete is when it extends the base and Incomplete does not extends the base.

• Join by bone is Complex sindactuly

• Medial deviation of proximal phalanx

  • Test for flatfoot is made by subtracting the patience age from 7 for Valmassy's rule

Flat and Cavus Feet

• Congenital flatfeet occur in: Calcaneovalgus Convex pes valgus

• What direction does the heel and forffort move: occurs in - Valgus of heel : abduction of forefoot

• Siginficant heel valgus w/ Lateral calcaneous are are sidees of the Sagittal plane dominate flatfoot

• Forefoot abduction are seen in the transverse plane dominated flat foot

• Gold standard = CT in TC coalitoons but want to limits to children Asymptomatic : controversial occurs in a treatment of aflatfoot

• Restrciting the abnormal action of foot is made of the action of the foot

• Component of orthoic:

  • Angulated hard substance in both that corretices by reduction joint compensation is a post

• Ds is deep orthotic

• What actions and muscles do orthoess increase: it is STJ pronation

• Cavus defitomy and what happens

• High medial arch or an underdyig neuromuscular disease

• Pantarflesed 1st and often hemapares

Caovavarus on an X-ray

• If a left Hemipatic ,an has a left Cavovarous Deformit Three types of caovarous

Postenor:

• Increase of Calcenal pitchel w/Tibiatalar angle: 1650.

• On X -R

• Normal Mearys ,Normal AntenotCavus:

• Increased the Mearyo & Calcenaal pitch Decreased TIbitalar Angle

  • on at X-ra

• Test for a flatfoot is made by sabrtaction age from 7

Mixed Cavus -On an X-ray

• Test for a flatfoot is made by sabrtaction age from 7 There is an incase the Meary The Normal tibitarar Angle .1

2. Three signs of a coalition a. Talar breaking b. . C sign c. Anrearrrs d. lArogenrc (overcotteo Normal

Questions cover the suggested presence of femoral torsion, STJ supination and pronation, and forefoot varus. Also addresses ligamentous laxity, forefoot to rearfoot relationships, and heel bisection axis. It also covers midtarsal joint subluxation and differentiation of os trigonum from fractures.