# Anatomical Variations in Bilateral Hand Oligodactyly: A Case Analysis of Cleft Hand

## TL;DR

This study examines the anatomical variations in a rare hand condition with fewer than five fingers, offering insights into its complexity and implications for surgery and developmental biology.

## Contribution

The study provides detailed anatomical dissection of bilateral hand oligodactyly, revealing structural variations that inform surgical approaches and developmental biology.

## Key findings

- Diverse anatomical variations were observed in hand structures such as tendons and metacarpals.
- Connections between flexor and extensor tendons were identified, differing between the two hands.
- The findings highlight the developmental complexity of hand oligodactyly and its relevance to congenital anomalies.

## Abstract

Background: Hand oligodactyly is a rare congenital malformation characterized by fewer than five digits. Although several clinical and radiological studies have been reported, detailed anatomical investigations remain scarce. This study aimed to describe the morphological characteristics of bilateral hand oligodactyly through dissection. Case Presentation: A bilateral hand oligodactyly with thumb and 3 fingers on each hand was found in a 77-year-old Korean female donor. The study was approved by the Institutional Review Board of Sungkyunkwan University (IRB No. SKKU 2023-02-012). Results: Diverse variations were observed in most structures of the hand, including the palmar aponeurosis, tendons of the flexor digitorum superficialis, the flexor digitorum profundus, and the flexor pollicis longus, lumbricals, interossei, and metacarpals. Connections between flexor and extensor tendons were also found, and each variation differed between the two hands. Conclusions: These structural differences highlight the developmental complexity of hand oligodactyly and offer valuable insights for facilitating appropriate surgical strategies. This study has also provided new insights into congenital anomalies that underscore their relevance in developmental biology.