Spondylometaphyseal dysplasia, Schmidt type

What it is

From: Orphanet

Spondylometaphyseal dysplasia, Schmidt type is characterized by short stature, myopia, small pelvis, progressive kypho-scoliosis, wrist deformity, severe genu valgum, short long bones, and severe metaphyseal dysplasia with moderate spinal changes and minimal changes in the hands and feet.

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.

Abnormal metaphysis morphology · Very frequent (99-80%)

An abnormality of one or more metaphysis, i.e., of the somewhat wider portion of a long bone that is adjacent to the epiphyseal growth plate and grows during childhood.

Abnormality of the vertebral column · Very frequent (99-80%)

Any abnormality of the vertebral column.

Metaphyseal dysplasia · Very frequent (99-80%)

The presence of dysplastic regions in metaphyseal regions.

Abnormality of the epiphysis of the femoral head · Frequent (79-30%)

Any abnormality of the proximal epiphysis of the femur.

Abnormality of the ilium · Frequent (79-30%)

An abnormality of the ilium, the largest and uppermost bone of the pelvis.

Abnormality of the knee · Frequent (79-30%)

An abnormality of the knee joint or surrounding structures.

Coxa vara · Frequent (79-30%)

Coxa vara includes all forms of decrease of the femoral neck shaft angle (the angle between the neck and the shaft of the femur) to less than 120 degrees.

Disproportionate short-trunk short stature · Frequent (79-30%)

A type of disproportionate short stature characterized by a short trunk but a average-sized limbs.

Genu valgum · Frequent (79-30%)

The legs angle inward, such that the knees are close together and the ankles far apart.

Hip dysplasia · Frequent (79-30%)

The presence of developmental dysplasia of the hip.

Narrow greater sciatic notch · Frequent (79-30%)

A narrowing of the sacrosciatic notch, i.e., the deep indentation in the posterior border of the hip bone at the point of union of the ilium and ischium.

Platyspondyly · Frequent (79-30%)

A flattened vertebral body shape with reduced distance between the vertebral endplates.

Scoliosis · Frequent (79-30%)

The presence of an abnormal lateral curvature of the spine.

Severe short stature · Frequent (79-30%)

A severe degree of short stature, more than -4 SD from the mean corrected for age and sex.

Other findings in the same source

From: Orphanet

Additional reported features include Short iliac bones (Frequent (79-30%)); Abnormality of the wrist (Occasional (29-5%)); Cleft soft palate (Occasional (29-5%)); Gastroesophageal reflux (Occasional (29-5%)); Gastrostomy tube feeding in infancy (Occasional (29-5%)); Irregular iliac crest (Occasional (29-5%)); Kyphoscoliosis (Occasional (29-5%)); Micrognathia (Occasional (29-5%)); Myopia (Occasional (29-5%)); Nasogastric tube feeding in infancy (Occasional (29-5%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

Adolescent; Childhood; Infancy

Inheritance in the source

From: Orphanet

Autosomal dominant

Frequency and the population described

From: Orphanet

Reported case(s): 7.0; Worldwide. This is a published case count, not prevalence. Point prevalence: <1 / 1 000 000; Worldwide; Class only.

Understanding the inheritance label

From: MedlinePlus Genetics

An autosomal dominant pattern means that one altered copy of a relevant gene can be sufficient for the condition. Some affected people inherit the change; others have a new change without an affected parent. The precise finding, family history and condition determine what this means for relatives.

Which doctor should you see?

The suggested department for discussing Spondylometaphyseal dysplasia, Schmidt type is Orthopaedics, with a orthopaedic specialist 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.

• What explains the change in pain, movement or function?
• Which activities need adjustment while the diagnosis is being clarified?
• What are the roles of rehabilitation, observation and surgery in this situation?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Spondylometaphyseal dysplasia, Schmidt type. 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.