Arch Hand Microsurg.  2024 Mar;29(1):1-23. 10.12790/ahm.23.0055.

Congenital hand differences: a comprehensive literature review

• Choi J
• Kwon ST
• Kim BJ

• KMID: 2553167
• DOI: http://doi.org/10.12790/ahm.23.0055

Abstract

Upper extremity anomalies are the second most common type of congenital malformations. Approximately 1% to 3% of newborns are born with congenital anomalies, and among them, roughly 10% have upper extremity anomalies. Congenital hand anomalies are often isolated phenomena but may also coexist with other congenital anomalies or syndromes. These anomalies cause not only aesthetic concerns, but also significant functional deficits and psychological issues for children and their families. Surgeons should conduct a thorough examination to make an accurate diagnosis and provide appropriate treatment or refer the patient to a specialized clinic if necessary. Operative procedures should aim to restore both function and aesthetics. This article reviews the embryology of the hand, the classification of congenital hand anomalies, and the clinical features and treatment of common major congenital hand anomalies.

Keyword

Congenital hand deformities; Embryology; Classification

Figure

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  Fig. 1. Signaling centers and coordinate axes of the limb bud. Pr, proximal; Di, distal; Rad, radial; Uln, ulnar; Do, dorsal; Vo, volar; AER, apical ectodermal ridge; ZPA, zone of polarizing activity; PZ, progress zone. Modified from Oberg et al. [6] with permission of Georg Thieme Verlag KG.

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  Fig. 2. Mechanism of determining the number of digits. Modified from Oberg et al. [16] with permission of International Federation of Societies for Surgery of the Hand.

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  Fig. 3. Wassel classification of polydactyly.

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  Fig. 4. The left hand shows postaxial polydactyly type B. The light hand and both feet show postaxial polydactyly type A. Postaxial polydactyly often affects both hands and feet and is associated with an autosomal dominant genetic inheritance. (Sourced from the Department of Plastic and Reconstructive Surgery at Seoul National University Hospital, with informed consent from the legal guardians of the patients.)

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  Fig. 5. Preoperative X-ray and clinical photograph of a case of central polydactyly. (A) X-ray and clinical photo after several operations. (B) Despite multiple surgeries, many patients still experience issues, such as finger deformities and joint stiffness. (Sourced from the Department of Plastic and Reconstructive Surgery at Seoul National University Hospital, with informed consent from the legal guardians of the patients.)

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  Fig. 6. Simple incomplete-type syndactyly (A) and complex complete-type syndactyly (B, C). (Sourced from the Department of Plastic and Reconstructive Surgery at Seoul National University Hospital, with informed consent from the legal guardians of the patients.)

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  Fig. 7. Clinical photographs and X-rays of syndactyly in Apert syndrome. (A) Upton type I, (B) type II, and (C) type III. (Sourced from the Department of Plastic and Reconstructive Surgery at Seoul National University Hospital, with informed consent from the legal guardians of the patients.)

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  Fig. 8. Results of epiphysiodesis in left index finger macrodactyly. (A) A preoperative hand X-ray. (B) A hand X-ray taken at postoperative 7 years. Note that longitudinal growth is well controlled, but circumferential growth is not controlled. (Sourced from the Department of Plastic and Reconstructive Surgery at Seoul National University Hospital, with informed consent from the legal guardians of the patients.)

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  Fig. 9. A patient with constriction band syndrome and syndactyly. (A) Preoperative clinical photograph. (B) The results after Z- and W-plasty, and syndactyly division with a skin graft. (Sourced from the Department of Plastic and Reconstructive Surgery at Seoul National University Hospital, with informed consent from the legal guardians of the patients.)

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  Fig. 10. After the pollicization, the structures in the original index finger that correspond to the structures of the new thumb are described in Fig. 10 and Table 7. DP, distal phalanx; DIPJ, distal interphalangeal joint; IPJ, interphalangeal joint; MP, middle phalanx; PP, proximal phalanx; PIPJ, proximal interphalangeal joint; MPJ, metacarpophalangeal joint; M, metacarpal bone; CMCJ, carpometacarpal joint; Trapez, trapezium; PI, palmal interossei; AddP, adductor pollicis; DI, dorsal interossei; AbPB, abductor pollicis brevis; EIP, extensor indicis proprius; EPL, extensor pollicis longus; EDC, extensor digitorum communis; AbPL, abductor pollicis longus. Modified from Chang et al. [2] with permission of Elsevier.

Reference

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