distal arthrogryposis type 7

Distal Arthrogryposis Type 7 (DA7) Overview

Distal arthrogryposis type 7, also known as trismus-pseudocamptodactyly syndrome or Hecht syndrome, is a rare genetic disorder. The condition is characterized by two primary features:

• Trismus: Inability to fully open the mouth
• Pseudocamptodactyly: A deformity of the fingers and toes that resembles camptodactyly (a flexion contracture)

This condition is caused by a mutation in the MYH8 gene. The symptoms and characteristics of DA7 can vary, but it often involves short stature, mild foot deformities, and short muscles and tendons.

Key Features

• Rare genetic disorder
• Trismus: inability to fully open the mouth
• Pseudocamptodactyly: deformity of fingers and toes resembling camptodactyly
• Short stature
• Mild foot deformities
• Short muscles and tendons

References

1. The trismus-pseudocamptodactyly syndrome is a distal arthrogryposis characterized by an inability to open the mouth fully (trismus) and pseudocamptodactyly in [4].
2. A rare, genetic, distal arthrogryposis characterized by pseudocamptodactyly, mild foot deformities, moderately short stature, and short muscles and tendons is described in [5].
3. Arthrogryposis is often used as shorthand to describe multiple congenital contractures that affect two or more different areas of the body, which includes DA7 in [6].

Distal Arthrogryposis Type 7: Key Signs and Symptoms

Distal arthrogryposis type 7 is a rare genetic disorder characterized by specific musculoskeletal abnormalities. The following are the key signs and symptoms associated with this condition:

• Trismus: A condition where there is limited opening of the jaw, making it difficult to speak or eat [9].
• Pseudocamptodactyly: A deformity of the fingers where they appear bent or curved, but can still be straightened [6].
• Palmar flexion at the wrists: The hands are positioned in a way that the palms face downwards and the wrists are flexed [9].
• Extension at the metacarpophalangeal joints: The joints between the fingers and the hand are extended, making it difficult to bend the fingers [9].

These symptoms can vary in severity and may be accompanied by other musculoskeletal abnormalities. It is essential for individuals with distal arthrogryposis type 7 to receive proper medical attention and care to manage their condition effectively.

References: [6] - A rare, genetic, distal arthrogryposis characterized by pseudocamptodactyly, mild foot deformities, moderately short stature, and short muscles and tendons. [9] - Distal arthrogryposis type 7 is characterized by trismus, pseudocamptodactyly, palmar flexion at the wrists, extension at the metacarpophalangeal joints...

Diagnostic Tests for Distal Arthrogryposis Type 7

Distal arthrogryposis type 7 (DA7), also known as trismus-pseudocamptodactyly syndrome, is a rare congenital disorder characterized by joint contractures and muscle weakness. Diagnosing DA7 can be challenging due to its rarity and the complexity of the condition.

Clinical Diagnosis

The clinical diagnosis of DA7 typically involves a combination of physical examination, medical history, and imaging studies (such as X-rays, CT scans, or MRI). A healthcare provider may use photography to document the extent of deformities and assess progress during treatment [6].

Genetic Testing

Genetic testing is an essential tool for diagnosing DA7. The condition is caused by mutations in the MYH8 gene, which codes for a muscle protein called myosin heavy chain 8. Genetic testing can identify these mutations, confirming the diagnosis of DA7.

• A 78-gene panel that includes assessment of non-coding variants is ideal for patients with a clinical suspicion of arthrogryposis or fetal akinesia [7].
• Exome-based next-generation sequencing (NGS) with CNV analysis can also be used to diagnose DA7, as it allows for cost-effective reflexing to PGxome or other exome-based testing approaches [3].

Other Diagnostic Tests

While not specific to DA7, other diagnostic tests may be used in conjunction with clinical and genetic testing to rule out other conditions that may present similarly. These include:

• Skeletal muscle biopsy: This test can help diagnose other congenital myopathies or dystrophies, although DNA diagnostic tests are not yet readily available for these conditions [9].
• Imaging studies (such as X-rays, CT scans, or MRI): These tests can help assess the extent of joint contractures and muscle weakness.

References

[1] Context result 4 [3] Context result 3 [6] Context result 6 [7] Context result 7 [9] Context result 9

Based on the search results, it appears that there are limited treatment options for distal arthrogryposis type 7 (trismus-pseudocamptodactyly), and drug treatment is not a well-established approach.

However, according to search result [4], acetylcholine treatment has been found to elicit a response in some patients with pterygium syndromes, which are related to distal arthrogryposis type 7. This suggests that there may be some potential for drug treatment in this condition, although it is not a completely successful approach.

Additionally, search result [6] mentions capsulotomy as a surgical treatment option, but does not specifically mention drug treatment.

It's worth noting that the goals of treatment for distal arthrogryposis type 7 include lower-limb alignment and establishment of stability for ambulation (search result [5]), which may involve a combination of physical therapy, bracing, casting, and other interventions.

Overall, while there is some limited information on potential drug treatments for distal arthrogryposis type 7, it appears that this approach is not well-established or widely recommended at present.

• Acetylcholine treatment has been found to elicit a response in some patients with pterygium syndromes [4].
• Capsulotomy is a surgical treatment option for distal arthrogryposis type 7, but does not specifically mention drug treatment [6].
• The goals of treatment include lower-limb alignment and establishment of stability for ambulation [5].

Differential Diagnosis of Distal Arthrogryposis Type 7

Distal arthrogryposis type 7 (DA7), also known as trismus-pseudocamptodactyly syndrome, is a rare distal arthrogryposis characterized by an inability to fully open the mouth (trismus) and contractures in the hands. When attempting to establish a differential diagnosis for DA7, it's essential to consider various conditions that may present with similar symptoms.

Conditions to Consider:

• Bony fusion (symphalangism, coalition, synostosis): This condition involves the abnormal fusion of bones, which can lead to joint contractures and limited mobility.
• Contractural arachnodactyly (Beals syndrome): A rare genetic disorder characterized by long fingers and toes, joint contractures, and other skeletal abnormalities.
• Multiple pterygium syndromes: A group of disorders that feature webbing or redundancy of the skin between various body parts, often accompanied by joint contractures.
• Amyoplasia: A type of arthrogryposis characterized by severe joint contractures, muscle weakness, and other systemic features.

Other Considerations:

• Neuropathic abnormalities: Malformations or malfunctions of the central and peripheral nervous system can lead to arthrogryposis.
• Recessive diseases: Certain genetic disorders, such as those affecting the musculoskeletal system, may present with distal contractures.

References:

• [1] Cubberley D, Morris C, Carey J. Prenatal diagnosis of distal arthrogryposis. American Journal of Medical Genetics. 1988;29(3):...
• [5] Differential Diagnosis[edit | edit source]
• [9] Jul 11, 2024 - Neuropathic abnormalities
• [10] Distal Arthrogryposis, as the name suggests, affects the distal parts of the limbs, and it can occur in the absence of any primary neurological disorder, or, indeed, any type of muscular disorder (Bamshad et al., 2009).
• [12] The differential diagnoses considered in the index patient were distal arthrogryposis (DA) syndrome, cerebroculofacioskeletal syndrome, and Pena Shokier syndrome. ... Bian C, Li X, Man X, Ge W, Han W, et al. Molecular prenatal diagnosis for hereditary distal arthrogryposis type 2B. Prenat Diagn. 2007; 27:468–70. [Google Scholar]
• [13] Table 7 lists some of the common disorders in these three categories (for an extensive differential diagnosis refer to Chapter 161 in Emery and Rimoin ... (Hall type DA IIE may be part of Amyoplasia spectrum) – sporadic Distal arthrogryposis Shalev type, mainly uppers and ptosis – AR Distal arthrogryposes absent teeth, distinct face ...
• [14] Distal arthrogryposes are a group of syndromes with congenital contractures primarily involving the hands and feet, which often are associated with abnormal facies, and are transmitted by autosomal dominant inheritance. ... Arthrogryposis / diagnosis Counseling Facies Hand Deformities, Congenital / classification* ...
• [15] AMC: amyoplasia and distal arthrogryposis Eva Kimber1 Received: 7 September 2013/Accepted: 7 November 2013/Published online: 4 November 2015 ... arthrogryposis, differential diagnosis can be difficult. It is, however, important to make as specific a diagnosis as ... type I with only distal joint involvement and characteristic hands