*4.6.2. Dysplastic nails*

Syndrome, Pallister-Hall Syndrome, Smith-Lemil-Opitz Syndrome, Trisomy 13, Trisomy 18, Short Rib Polydactyly Syndrome Type I (Saldino-Noonan Type) (Majewski type), Trisomy 21, Townes-

Usually, polydactyly is diagnosed antenatally, but if it is postnatally discovered, it requires paraclinical investigations in order to be included in one of the genetic syndromes, except for cases of family history. The investigations are performed using imaging techniques (MRI, CT scan, ultrasound examination), followed by genetic consultation in case of association with other malformations. The most commonly associated malformations are syndactyly, hypoplasia or aplasia of long bones, hydrocephalus, microcephaly, spina bifida, ventricular septal defect, atrial septal defect, esophageal atresia, duodenal atresia, anal imperfection, abdominal wall defects, renal agenesis, polycystic kidney disease, hydronephrosis, diaphragmatic her-

In the case of isolated polydactyly, no treatment is required. If this anomaly affects the mobil-

Syndactyly is one of the most common congenital limb malformations involving the fusion of two or more fingers due to the failure of separation process during the development of limbs in the first trimester. In the lower limbs, the most common location is between the second and

It is a heterogeneous clinical phenotype, as it may be: unilateral or bilateral, symmetrical or asymmetrical, partial or complete, cutaneous or bony, involving only the phalanges and/ or

Partial syndactyly of the second and third toe may appear as a clinically isolated phenotype

• Pfeiffer syndrome [76–79] - type V acrocephalopolysyndactyly has as its etiology a dominant autosomal genetic defect in which mutations occur in the FGFR1 gene (fibroblast growth factor receptor 1) and in the FGFR2 gene (fibroblast growth factor receptor 2). In this syndrome, the partial syndactyly of the second and third toe is accompanied by other malformations such as craniosynostosis, facial hypoplasia, hypertelorism, brachydactyly. • Carpenter syndrome - type II acrocephalopolysyndactyly is an autosomal recessive genetic disorder in which mutations occur in RAB23, a hydrolysis involved in transmembrane regulation [80]. Carpenter syndrome associates, besides partial syndactyly and polydactyly,

• Smith-Lemli-Opitz syndrome is an autosomal recessive genetic disorder of cholesterol biosynthesis [81]. This syndrome associates with syndactyly and microcephaly, micrognathia,

Partial syndactyly of the second and third toe does not affect the motor function, and therefore

genital malformations, auricular malformations, autism spectrum disorders.

(the most common is zygodactyly) [75] or may be associated with syndromes such as:

metatarsal bone, or may extend to tarsal bones or even the calf bones.

with auricular, cardiac and genital abnormalities.

ity and gross/fine movements of the fingers/hands, the treatment is always surgical.

Brocks Syndrome.

nia, anophthalmia, cheilopalatoschisis.

524 Congenital Anomalies - From the Embryo to the Neonate

*4.6.1. Partial syndactyly of the second and third toe*

**4.6. Minor foot anomalies**

the third finger [75].

does not require correction.

Insufficient development of nails [82] may occur in isolation or in many genetic malformations such as:

