syndactyly type 8

Syndactyly Type 8: A Rare Congenital Limb Malformation

Syndactyly type 8, also known as metacarpal 4-5 fusion or metacarpals 4 and 5 fusion, is a rare non-syndromic congenital limb malformation. It is characterized by the unilateral or bilateral fusion of the fourth and fifth metacarpals, with no other associated abnormalities.

Key Features:

• Unilateral or bilateral fusion of the fourth and fifth metacarpals
• Shortened fourth and fifth metacarpals with excessive separation between their distal ends
• Marked ulnar deviation of the little finger and an inability to bring the 5th finger in parallel with the other fingers

Causes:

Syndactyly type 8 is caused by genetic mutations, also known as pathogenic variants. These mutations can be hereditary or occur randomly when cells are dividing.

Prevalence:

The exact prevalence of syndactyly type 8 is unknown, but it is considered a rare condition.

References:

• [1] A rare non-syndromic syndactyly characterized by unilateral or bilateral fusion of the 4th and 5th metacarpals with no other associated abnormalities. (Source: #11)
• Syndactyly type 8 is a rare, genetic, non-syndromic, congenital limb malformation characterized by unilateral or bilateral fusion of the fourth and fifth metacarpals with no other associated abnomalities. (Source: #3, #13)
• Syndactyly type 8 is caused by genetic mutations, also known as pathogenic variants. (Source: #2)

Syndactyly type 8, also known as fusion of the fourth and fifth metacarpals, is a rare congenital limb malformation characterized by the fusion of these two bones in the hand. The symptoms of this condition can vary depending on the severity of the fusion.

Key Symptoms:

• Fusion of the fourth and fifth metacarpals (bones in the hand)
• Shortening of the fused fourth and fifth fingers
• Excessive separation between the distal ends of the fused bones, resulting in marked ulnar deviation of the little finger
• Inability to bring the 5th finger into opposition with the other fingers

Additional Symptoms:

• The fusion may be complete or partial, depending on the severity of the condition.
• In some cases, the fusion may involve only skin and soft tissue, while in others it may also involve bone, nerves, and blood vessels.

According to [6], the hallmark of syndactyly type 8 is the fusion of fourth and fifth metacarpals (Figure 2). Additional symptoms may involve shortening of fused fourth and fifth fingers.

Diagnostic Tests for Syndactyly Type 8

Syndactyly type 8, a rare non-syndromic congenital limb malformation, can be diagnosed through various diagnostic tests. Here are some of the tests that may be used to diagnose syndactyly type 8:

• Clinical evaluation: A thorough physical examination by a healthcare provider is usually the first step in diagnosing syndactyly type 8 [7].
• Radiography: X-rays or other imaging studies may be ordered to confirm the diagnosis and assess the extent of fusion between the fourth and fifth metacarpals [5].
• Genetic testing: A genetic test, such as a 21-gene panel that includes assessment of non-coding variants, can be used to identify the underlying genetic cause of syndactyly type 8 [4].

It's worth noting that the diagnosis of syndactyly type 8 is typically made shortly after birth based on a physical examination. However, in some cases, additional diagnostic tests may be ordered to confirm the diagnosis and rule out other potential causes.

References:

• A Cassim (2022) [5]
• S Malik (2012) [6]
• Context search results 4, 7, 8

Syndactyly type 8 is a rare, genetic, non-syndromic, congenital limb anomaly characterized by the fusion of two or more fingers. While there are no specific drug treatments mentioned in the search results for this condition, it's essential to note that treatment typically involves surgical intervention.

However, according to search result [7], syndactyly type 8 is a rare condition, and as such, there may be limited information available on its management. In general, treatment for syndactyly often focuses on correcting the physical deformity through surgery.

Regarding drug treatment specifically, it's worth noting that some search results mention the importance of avoiding certain medications in patients with syndromes that involve cardiac abnormalities [1]. However, this does not directly relate to the use of drugs as a primary treatment for syndactyly type 8.

In terms of managing non-cardiac manifestations of syndactyly, such as respiratory infections, antibiotics may be prescribed. However, it's crucial to choose medications that do not cause QT prolongation [1].

It appears that surgical correction is the primary approach to treating syndactyly type 8, with no specific mention of drug treatment in the search results provided.

References: [1] Search result 1 [7] Search result 7

Syndactyly type 8 (SD8) is a rare form of syndactyly, characterized by the fusion of the fourth and fifth metacarpals. The differential diagnosis for SD8 involves distinguishing it from other conditions that may present with similar symptoms.

Key Features to Consider:

• Fusion of the fourth and fifth metacarpals
• Shortened fourth and fifth metacarpals
• Excessive separation between the distal ends of the metacarpals
• Marked ulnar deviation of the little finger
• Inability to bring the fifth finger in parallel with the other fingers

Differential Diagnosis:

• Syndactyly type 9 (SD9): This condition is characterized by mesoaxial synostotic syndactyly, which can present with similar symptoms to SD8. However, SD9 typically involves fusion of the metacarpals and phalanges, whereas SD8 only affects the fourth and fifth metacarpals.
• Complex Syndactyly: This condition involves bony fusion of adjacent digits, including soft tissue and bone. While it can present with similar symptoms to SD8, complex syndactyly typically involves more extensive fusion and may affect multiple digits.
• Other Rare Conditions: There are several other rare conditions that may present with similar symptoms to SD8, including non-syndromic syndactyly and split hand/foot malformation type 2 (SHFM2).

Diagnostic Approach:

To diagnose SD8, a comprehensive evaluation is necessary, including:

• Clinical examination
• Radiographic imaging (e.g., X-rays)
• Genetic testing to rule out other conditions

A diagnosis of SD8 can be confirmed through genetic analysis, which has identified the condition as being associated with chrXq26 and the SHFM2 gene.

References:

[3] by H Ahmed · 2017 · Cited by 88 — It can be divided into 2 subtypes: Orel-Holmes type and Lerch type. SD8 is associated with chrXq26 and the split hand/foot malformation type 2 (SHFM2) gene. [11] A rare non-syndromic syndactyly characterized by unilateral or bilateral fusion of the 4th and 5th metacarpals with no other associated abnormalities.