Major groups based on 2x2 table (transverse vs longitudinal, terminal vs intercalary):
(1) terminal and transverse
(2) intercalary and transverse
(3) terminal and longitudinal
(4) intercalary and longitudinal
Upper Extremity
Terminal and transverse:
(1) absence of all digits (adactylia)
(2) absence of hand (acheiria)
(3) absence of forearm and hand (hemimelia)
(4) absence of entire limb (amelia)
Intercalary and transverse (phocomelia):
(1) absence of humerus
(2) absence of radius and ulna
(3) absence of humerus, radius and ulna)
Terminal and longitudinal:
(1) central (affecting digits 2, 3, 4)
(2) thumb with or without radius
(3) digits 3, 4, 5 with or without ulna
Intercalary and longitudinal (hemimelia):
(1) absence of radius
(2) absence of ulna
(3) absence of hypoplasia of scaphoid, trapezial and first metacarpal bone
Lower Extremity
Terminal and transverse:
(1) absence of all digits (adactylia)
(2) absence of foot (acheiria)
(3) absence of lower leg and foot (hemimelia)
(4) absence of entire limb (amelia)
Intercalary and transverse (phocomelia):
(1) absence of femur
(2) absence of tibia and fibula
(3) absence of femur, tibia and fibula
Terminal and longitudinal (hemimelia):
(1) central (affecting digits 2, 3, 4)
(2) great toe with or without long bone
(3) digits 3, 4, 5 with or without long bone
Intercalary and longitudinal (hemimelia):
(1) absence of tibia, fibula present
(2) absence of fibula, tibia present
