Case Report
DOI: 10.5152/TurkJPlastSurg.2016.1945
A Case of Familial Polydactyly From Turkey
Billur Sezgin
Clinic of Plastic, Reconstructive and Aesthetic Surgery, Erzurum Region Training and Research Hospital, Erzurum, Turkey
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Abstract
Polydactyly is among the most frequently encountered congenital anomalies of the extremities. Although it is usually presented in an isolated and sporadic manner, familial cases can also be rarely encountered. Such familial polydactyly cases usually follow an autosomal dominant inheritance with variable genetic penetration and are usually bilateral and symmetric. A case of rare familial polydactyly from Turkey
is presented. Four siblings, two girls and two boys, presented with bilateral, symmetric preaxial polydactyly affecting both hands and feet.
These siblings also had four other unaffected siblings along with an affected father and grandmother (the father’s mother). Although the
cases portrayed duplication at different levels, the general definition of familial polydactyly with bilateral, symmetric inheritance is observed
in these cases. Other rare familial polydactyly cases have been reported in the literature as well, and this case serves as a typical example of
this rare entity from Turkey.
Keywords: Familial polydactyly, inheritance pattern, preaxial polydactyly
INTRODUCTION
Polydactyly is one of the most frequently observed congenital limb anomalies and comes first in many epidemiological studies.1 An
anomaly group of highly heterogeneous nature, polydactyly mostly occurs as isolated and sporadic cases. Familial cases are rarer
and can manifest in various hereditary patterns.2 This study presents a rare incidence of familial polydactyly encountered in Turkey.
CASE PRESENTATION
Two of eight siblings, four girls and four boys who were aged 4–35 years living in Erzurum, presented to the plastic surgery clinic with
a complaint of difficulty in wearing shoes because of polydactyly (Figures 1,2). Both the 16-year-old female and 14-year-old male
patients had preaxial polydactyly on the two hands and feet. Direct radiographies revealed that the male patient had duplications of
both big toes that originated at the proximal phalanx, while the female patient additionally had a duplication of the first metatarsal
bone in the right foot (Figures 3,4). In both patients, although the thumbs were normal, there were complete duplications of the
second digit (Figures 2,5,6).
History revealed the presence of bilateral preaxial polydactyly on the hands and feet of four of the eight siblings (two females and
two males), while the remaining four siblings were unaffected. Their father had bilateral preaxial polydactyly only in the lower limb,
and their paternal grandmother was described to be the first polydactyly case in the family. As the two patients did not have complaints regarding their hands, the excess digits on the feet were excised (Figures 7, 8). No complications were encountered during
their recovery period.
DISCUSSION
Polydactyly is the most frequently encountered congenital limb anomaly with a known prevalence rate of 0.3–3.6/1000 live births
and an overall rate of 1.6–10.7/1000 individuals in the society.3 Males are affected twice as often. Phenotypically, polydactyly is a
Correspondence Author: Dr. Billur Sezgin
E-mail: [email protected]
©Copyright by 2016 Turkish Society of Plastic Reconstructive, and Aesthetic Surgery - Available online at www.turkjplastsurg.com.
Received: 15.12.2014
Accepted: 05.05.2015
Turk J Plast Surg 2016; 24(2): 94-6
highly heterogeneous anomaly group and is often isolated
and sporadic but can also accompany various limb anomalies or present as part of a number of syndromes.
While polydactyly is observed to more frequently involve
the upper extremity than the lower extremity, the right
hand is observed to be more affected than the left hand.
Polydactyly in the lower extremity exhibits the opposite,
with the left foot being more affected than the right foot.4
Pre- and postaxial polydactyly are the most common cases;
mesoaxial polydactyly, involving the third and fourth digits,
is rarely encountered. Most cases are sporadic and frequently present unilaterally. Familial cases are rare and usually
occur in bilateral symmetry as in our two cases.1 Our cases
were found to be consistent with the autosomal dominant
inheritance pattern, with a highly variable penetrance.
Sezgin B / Familial Polydactyly
and not the thumb. This profile is consistent with the highly
rare type III preaxial polydactyly described by Malik.1 The
most common preaxial polydactyly is type I, which is described as a duplication that affects the thumb.1
CONCLUSION
In the present cases, symmetric preaxial polydactyly was
identified on the hands and feet of four of the eight siblings.
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A distinguishing feature in this familial case was that the
preaxial polydactyly on the hands involved the second digit
Figure 1. The 16-year-old female patient presented with preaxial polydactyly on the two hands and feet. The figure shows
the duplications of the big toes on both feet
Figure 3. Direct radiography of the female patient showed
complete duplication of the big toe that originated at the
proximal phalanx of the left foot, and a metatarsal duplication
of the big toe in the right foot
Figure 2. The 14-year-old male patient presented with preaxial polydactyly on the two hands and feet. The figure shows
the duplications of the big toes on both feet and of the second digits on both hands
Figure 4. Direct radiography of the male patient showed
complete duplication of the big toe that originated at the
proximal phalanx on both feet. The metatarsal bones on both
feet are shown to be of abnormal appearance, consistent with
a fusion
Sezgin B / Familial Polydactyly
Turk J Plast Surg 2016; 24(2): 94-6
Figure 8. View of the male patient in the third postoperative week
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Figure 5. Bilateral direct radiography showed that the thumbs
were not affected in the male patient
Although they presented with duplication at different levels,
on the whole, hereditary bilateral preaxial polydactyly, which
is frequently described in familial polydactyly cases, was present in the family members. The absence of polydactyly in four
siblings can be explained by reduced penetrance. Apart from
presenting a typical case of rare familial polydactyly, the presence of a highly rare subtype of preaxial polydactyly on the
hands makes this report a significant familial case.
Informed Consent: Written informed consent was obtained from patients who participated in this case.
Peer-review: Externally peer-reviewed.
Conflict of Interest: No conflict of interest was declared by the author.
Figure 6. Preaxial polydactyly observed on the two hands of the
female patient, similar to that of the male patient, occurred with
the duplications of the second digit and did not affect the thumbs
Financial Disclosure: The author declared that this study has received no financial support.
REFERENCES
1. Malik S. Polydactyly: phenotypes, genetics and classification.
Clin Genet 2014; 85(3): 203-12. [CrossRef]
2. Karaaslan O, Tiftikcioglu YO, Aksoy HM, Kocer U. Sporadic familial
polydactyly. Genet Couns 2003; 14(4): 401-5.
3. Mellin GW. The frequency of birth defects. In: Birth defects. Philadelphia, PA: Lippincott JB, 1963: 1-17.
4. Castilla E, Paz JE, Mutchinick O, Munoz E, Giorguitti E, Gelman Z.
Polydactyly a genetic study in South America. Am J Hum Genet
1973; 25(4): 405-12.
Figure 7. View of the female patient in the third postoperative week