From the Guidelines
The split hand sign, also known as split-hand/split-foot malformation, is a congenital anomaly characterized by a median cleft of the hand or foot, and it is clinically significant as it can be associated with various genetic syndromes and conditions. The split hand sign is a rare congenital malformation that can occur in isolation or as part of a genetic syndrome, such as ectrodactyly-ectodermal dysplasia-clefting syndrome [ 1 ]. This condition is characterized by a median cleft of the hand or foot, resulting in a split or divided appearance. The significance of the split hand sign lies in its potential association with underlying genetic conditions, which can have implications for the patient's overall health and quality of life.
Clinical Implications
When evaluating a patient with the split hand sign, it is essential to consider the potential for underlying genetic syndromes or conditions. The split hand sign can be associated with various conditions, including ectrodactyly-ectodermal dysplasia-clefting syndrome, which can affect not only the hands and feet but also other systems, such as the skin, hair, and teeth [ 1 ]. Early recognition and diagnosis of these conditions can lead to timely intervention and management, improving the patient's quality of life and reducing the risk of complications.
Management and Treatment
The management and treatment of the split hand sign depend on the underlying condition or syndrome associated with it. In some cases, surgical intervention may be necessary to correct the malformation or improve function [ 1 ]. However, the decision to undergo surgery should be made on a case-by-case basis, taking into account the potential benefits and risks of the procedure. In general, the goal of treatment is to improve the patient's quality of life, reduce pain and discomfort, and enhance functional ability.
Key Considerations
- The split hand sign is a rare congenital malformation that can occur in isolation or as part of a genetic syndrome.
- Early recognition and diagnosis of underlying genetic conditions are crucial for timely intervention and management.
- Surgical intervention may be necessary to correct the malformation or improve function, but the decision to undergo surgery should be made on a case-by-case basis.
- The goal of treatment is to improve the patient's quality of life, reduce pain and discomfort, and enhance functional ability.
From the Research
Definition and Characteristics
- Split-hand/split-foot malformation is a rare limb malformation characterized by median clefts of the hands and feet and aplasia/hypoplasia of the phalanges, metacarpals, and metatarsals 2.
- It presents with a deep median cleft of the hand and/or foot, aplasia/hypoplasia of the phalanges, metacarpals, and metatarsals 3.
- The condition is clinically and genetically heterogeneous and shows mostly autosomal dominant inheritance with variable expressivity and reduced penetrance 4.
Genetic Basis
- The autosomal dominant form of split-hand/split-foot malformation has been mapped to 7q21.3-q22.1, and the locus has been designated SHFD1 5.
- Seven chromosomal loci associated with isolated split-hand/foot malformation have been described, i.e., SHFM1 to 6 and SHFM/SHFLD 4.
- Three genes, i.e., TP63, WNT10B, and DLX5, are known to carry point mutations in patients affected by split-hand/foot malformation 4.
- A novel heterozygous FGFR1 mutation has been reported to cause split-hand/foot malformation syndrome 6.
Inheritance and Counseling
- Split-hand/split-foot malformation is usually inherited as an autosomal dominant form, but autosomal recessive and X-linked inheritance can also occur 2, 4.
- Genetic counseling can be challenging, especially in sporadic cases, but recent progress in understanding the pathogenesis of split-hand/foot malformation allows for the identification of causative genetic changes in about 50% of patients 4.
- Accurate genetic diagnosis can provide detailed counseling to couples, including the underlying cause, recurrence risks, and detailed management plan with preimplantation genetic diagnosis for future pregnancies 6.