Congenital Limb Deficiency Flashcards
discuss how bone formation occurs
enchondral: mesenchymal cells -> cartilage -> bone
- axial and appendicular skeleton
intramembranous: mesenchymal cells -> bone
- flat bones, skull, clavicle
discuss the primary centers of ossification
chondrocytes of long bone from which mag lengthen
occurs 4-8 wks p fertilization kaya limb defects occur at 4-6 wks
in midshaft of long bones
discuss the secondary centers of ossification
in chondroepiphysis and appear post natally
distal femur, proximal tibia, calcaneus, talus
what are the parts of long bone
epiphysis - secondary ossification center
physis - growth plate at end of bones; discrepancy happens here
metaphysis
diaphysis - shaft
perichondral ring - appositional growth
ratio of head height to body height at birth
1:4
ratio of head height to body height at maturity
1:7.5
height of child at 5 yo
height doubles
60% of adult height
height of child at 9 yo
80% of adult height
height of child in puberty
inc 1 cm/mo
what is congenital amputation
absence of all or part of limb at birth
upper ex more common in general
1st trimester is crucial
most common UE congenital ampu
terminal transradial defiency on (L)
most common LE congenital ampu
fibular longitudinal deficiency
risk factors for congenital ampu
maternal DM
smoking
thalidomide
valproic acid
Ca channel blockers
maternal occupation
uterine abnormalities
causes of congenital ampu
vascular disruption - amniotic band syndrome
vascular malformations - poland
genetic - sponty point mutation
unkown
genetically determined syndromes
holt-oram and fanconi
discuss fanconi syndrome
renal dysfunction
underdeveloped, missing or dupli thumb
shortned or missing radius
shortened or curved FA
hand perpendicular to FA
impaired wrist, finger and elbow movement
discuss holt-oram syndrome
heart hand syndrome
UE deformity + congenial heart defect
absence of limb (OG)
amelia
partial absence of limb (OG)
meromelia
flipper like appendages of limb (OG)
phocomelia
absence of half limb (OG)
hemimelia
absence of hand or foot (OG)
acheira
absence of metacarpal or metatarsal (OG)
adactyly
absence of finger or toe (OG)
aphalangia
ISP classification
transverese level: no distal parts; absent onwards
longitudinal: names bones affected starting from most proximal; has distal parts
most common longitudinal upper limb deficiency
radial ray
most common longitudinal lower limb deficiency
hypoplasia of fibula
