Table 4

Differential diagnoses of NPS

Small patella syndromeSmall or absent patellaeDefective ossification at the ischiopubic junction and ischial hypoplasia 67– 70
OMIM 147891Recurrent patella dislocationsInfra-acetabular “axe-cut” notch
(ischiopatellar dysplasia, coxo-podo-patellar syndrome, Scott-Toar syndrome)Pelvic anomaliesNo nail changes
No elbow changes
No renal involvement
No ocular involvement
Patella aplasia-hypoplasiaIsolated aplasia or hypoplasia of the patellaNo nail changes 71– 73
OMIM 168860 PTLAHNo elbow changes
No renal involvement
No ocular involvement
Familial recurrent dislocation of the patellaFamilial tendency towards patella dislocation 74
OMIM 169000
Meier-Gorlin syndromeAbsent patellaeMicrotia 75– 78
OMIM *224690Dislocation of the radial headMarkedly short stature
Delayed bone age
Characteristic facial appearance
Autosomal recessive inheritance
Genitopatellar syndromeAbsent patellaeHypoplasia of the ischia and iliac bones 79
OMIM *606170Renal anomaliesGenital anomalies
Flexion deformities of the knees and hipsFacial dysmorphism
Club footMicrocephaly
Mental retardation
renal manifestations are structural (multicystic kidneys or hydronephrosis) rather than functional
DOOR syndromeAbsent or poorly formed nailsLong thumbs and big toes, often with triphalangism 80
OMIM *220500Other fingers and toes are short owing to an absent or hypoplastic distal phalanx
Bilateral ptosis
Short broad nose with a broad nasal tip and Large nostrils
Structural renal tract abnormalities cataracts, optic atrophy
Dandy-Walker malformation, seizures
Autosomal recessive inheritance
Trisomy 8 mosaicismAbsent or hypoplastic patellaeSignificant learning difficulties and variable facial dysmorphism camptodactyly and progressive joint restriction usually of the fingers and toes 53
Limited elbow supination
Abnormal nails
Coffin-Siris syndromeAbsence or hypoplasia of the nails and patellaeNail hypoplasia usually affects the little finger nails 80
OMIM 135900Elbow dislocationFacial dysmorphism
Developmental delay
RAPADILINO syndromeRadial defects, absent or hypoplastic patellaeCleft palate, facial dysmorphism, short stature, radial defects include absent or hypoplastic thumbs and radii 80
OMIM 266280Dislocated jointsAutosomal recessive inheritance
Senior syndromeSmall nailsCharacteristic facial appearance, short stature, and mild intellectual impairment 81
OMIM 113477