Polydactyly: Clinical and molecular manifestations

Postaxial polydactyly: A case report highlighting genetic context, epidemiological trends, and management options

This case report examines a newborn with bilateral postaxial polydactyly type B, delivered by a 42-year-old mother with a history of third-degree consanguinity. The mother, having had no prior live births and one abortion, presented at 39 weeks gestation. The absence of prenatal care is noted, with its potential impact on prenatal diagnosis not assessed. The newborn, a healthy girl, weighed 3400 g with an Apgar score of 9/10. Radiographic and physical examination revealed vestigial sixth digits with rudimentary phalanges, influencing the surgical approach. This report underscores the importance of genetic counseling in cases of consanguinity and illustrates the multidisciplinary strategy necessary for managing polydactyly, from surgical considerations to genetic evaluation.

Surgical management of bilateral preaxial and postaxial polydactyly with syndactyly: A case report

INTRODUCTION AND IMPORTANCE

Polydactyly is the most common congenital malformation in the limbs. However, it is rare for a patient to exhibit concomitant preaxial and postaxial polydactyly alongside syndactyly in both limbs, and there are limited recommendations for such conditions. This report presents a case of bilateral preaxial and postaxial polydactyly with syndactyly of the feet.

PRESENTATION OF CASE

A 2-year-old girl was presented with an excess number of toes on both feet and an abnormal connection between the second and third toes. After a physical examination and plain radiography, the patient was diagnosed with bilateral preaxial and postaxial polydactyly with syndactyly. We performed a one-stage surgical correction consisting of ablation at the extra digit of bilateral great and little toes, followed by syndactyly release using z-plasty. The surgery was uneventful, and the parents were satisfied with the result.

DISCUSSION

A plain radiograph is necessary for pre-operative planning. We discarded the excess digits for cosmetics and soft and hard tissue for optimal function. It is necessary to preserve the soft tissues, remove the auxiliary digit, realign the digit, and restore the ligaments to preserve digit stability.

CONCLUSION

The complexity of this case required a meticulous surgical approach to address the structural abnormalities, restore functionality, and improve cosmetic appearance. In this case, the surgery can be performed in one procedure to minimize patient morbidity.

A Case of Postaxial Polydactyly Managed Under Local Anesthesia

Polydactyly is a common occurrence, observed as the presence of extra digit/s in the hands and feet. It can be categorized into preaxial, postaxial, and mesoaxial forms based on the location of the additional digit. In most instances only a single extra digit is present, research reports with more than one extra digit have been published. Most common management includes surgical excision under the influence of general anesthesia. An alternative approach by removing the pre-axial and post-axial supernumerary digit is carried out under local anesthesia in infants and small children, providing the additional benefit of fewer post-procedural complications. This is a case of a 5-month-old male child, with post-axial polydactyly of the left hand. He was managed by excision of the extra digit under the influence of local anesthesia. The patient recovered well and was discharged 3 days after the procedure with the advice of monthly follow-up until 3 months.

Whole-Genome Sequencing for Identifying Candidate Genes Related to the Special Phenotypes of the Taihu Dianzi Pigeon

The Taihu Dianzi pigeon is a breed native to China, and its special piebalding, crest, and polydactyly phenotypes are the result of artificial and natural selection. Here, we analyzed the genetic differences among three kinds of pigeons with different phenotypes at the genomic level. A selective sweep was conducted based on the fixation index (FST) and nucleotide diversity (π) ratio, and the results revealed that MC1R was related to the formation of the distinctive piebalding of the Taihu Dianzi pigeon. Combined with the results of genome-wide association studies, we identified candidate genes associated with the crest (SMYD and STOX2) and polydactyly (SLC52A3 and ANGPT4). The candidate genes identified in this study and their variants may be useful for understanding the genetic mechanism underlying the special phenotypes of the Taihu Dianzi pigeon. This study provides new insights into the genetic factors that may influence the formation of the special piebalding, crest, and polydactyly characteristics in pigeons.