Myopathic Ehlers-Danlos syndrome

What it is

From: Orphanet

A rare systemic disease characterized by congenital muscle hypotonia and/or muscle atrophy that improves with age, proximal joint contractures (knee, hip, elbow), and hypermobility of distal joints. Additional features include soft, doughy skin, atrophic scarring, delayed motor development, and myopathic findings in muscle biopsy. Abnormal craniofacial features have been reported in some patients. Molecular testing is obligatory to confirm the diagnosis.

Reported clinical features and what the terms mean

The following findings are associated with this condition in Orphanet. They are not a checklist for diagnosing yourself, and they do not all occur in every affected person. Some are examination, imaging or laboratory findings that cannot be recognised at home.

The frequency labels describe how often a finding was reported among people with the condition in the source. They do not give the chance that a person with that symptom has the condition. Definitions below reproduce HPO terminology; they explain the term, not the likely severity in an individual.

Flexion contracture · Very frequent (99-80%)

A flexion contracture is a bent (flexed) joint that cannot be straightened actively or passively. It is thus a chronic loss of joint motion due to structural changes in muscle, tendons, ligaments, or skin that prevents normal movement of joints.

Joint hypermobility · Very frequent (99-80%)

The capability that a joint (or a group of joints) has to move, passively and/or actively, beyond normal limits along physiological axes.

Atrophic scars · Frequent (79-30%)

Scars that form a depression compared to the level of the surrounding skin because of damage to the collagen, fat or other tissues below the skin.

Delayed ability to stand · Frequent (79-30%)

A failure to achieve the ability to stand up at an appropriate developmental stage. Most children begin to walk alone at 11 to 15 months of age. On average, children can stand while holding on at the age of 9 to 10 months, can pull up to stand and walk with one hand being held at 12 months, and can stand alone and walk well at 18 months.

Delayed ability to walk · Frequent (79-30%)

A failure to achieve the ability to walk at an appropriate developmental stage. Most children learn to walk in a series of stages, and learn to walk short distances independently between 12 and 15 months.

Distal joint hypermobility · Frequent (79-30%)

Lack of stability of a distal joint (e.g., finger).

Generalized muscle weakness · Frequent (79-30%)

Generalized weakness or decreased strength of the muscles, affecting both distal and proximal musculature.

Increased variability in muscle fiber diameter · Frequent (79-30%)

An abnormally high degree of muscle fiber size variation. This phenotypic feature can be observed upon muscle biopsy.

Motor delay · Frequent (79-30%)

A type of Developmental delay characterized by a delay in acquiring motor skills.

Myopathy · Frequent (79-30%)

A disorder of muscle unrelated to impairment of innervation or neuromuscular junction.

Skeletal muscle atrophy · Frequent (79-30%)

The presence of skeletal muscular atrophy (which is also known as amyotrophy).

Adducted thumb · Occasional (29-5%)

In the resting position, the tip of the thumb is on, or near, the palm, close to the base of the fourth or fifth finger.

Areflexia · Occasional (29-5%)

Absence of neurologic reflexes such as the knee-jerk reaction.

Blue sclerae · Occasional (29-5%)

An abnormal bluish coloration of the sclera.

Other findings in the same source

From: Orphanet

Additional reported features include Congenital contracture (Occasional (29-5%)); Congenital finger flexion contractures (Occasional (29-5%)); Congenital muscular torticollis (Occasional (29-5%)); Delayed fine motor development (Occasional (29-5%)); Elbow flexion contracture (Occasional (29-5%)); Exercise intolerance (Occasional (29-5%)); Failure to thrive (Occasional (29-5%)); Foot joint contracture (Occasional (29-5%)); High, narrow palate (Occasional (29-5%)); Hyperextensible skin (Occasional (29-5%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

Antenatal; Infancy; Neonatal

Inheritance in the source

From: Orphanet

Autosomal dominant; Autosomal recessive

Frequency and the population described

From: Orphanet

Reported case(s): 8.0; Worldwide. This is a published case count, not prevalence. Point prevalence: <1 / 1 000 000; Worldwide; Class only.

Which doctor should you see?

The suggested department for discussing Myopathic Ehlers-Danlos syndrome is Rheumatology, with a rheumatologist as the relevant type of clinician. General physician / Family Medicine; paediatrician for children. Referral depends on symptoms.

Additional services that may be relevant, depending on the findings, include: Clinical Genetics.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• Are the findings inflammatory, structural or due to another mechanism?
• Is there evidence that other organs need assessment?
• How will function and any treatment-related risks be monitored?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Myopathic Ehlers-Danlos syndrome. That gap does not mean that treatment is unavailable. A clinician needs to establish the diagnosis and review current guidance before recommending medicines, procedures, rehabilitation or other support.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.