Odontochondrodysplasia

What it is

From: Orphanet

A rare primary bone dysplasia characterized by the association of spondylometaphyseal dysplasia, generalized joint laxity, and dentinogenesis imperfecta. Main skeletal abnormalities comprise short stature, narrow chest, scoliosis, mesomelic limb shortening, and brachydactyly. Radiographic features include severe metaphyseal irregularities of the tubular bones, platyspondyly with coronal clefts, cone-shaped epiphyses of the hands, square iliac wings, and coxa valga. Additional extraskeletal manifestations like pulmonary hypoplasia, cystic renal disease, and non-obstructive hydrocephalus have also been reported.

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.

Cone-shaped epiphysis · Very frequent (99-80%)

Cone-shaped epiphyses (also known as coned epiphyses) are epiphyses that invaginate into cupped metaphyses. That is, the epiphysis has a cone-shaped distal extension resulting from increased growth of the central portion of the epiphysis relative to its periphery.

Dentinogenesis imperfecta · Very frequent (99-80%)

Developmental dysplasia of dentin.

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.

Micromelia · Very frequent (99-80%)

The presence of abnormally small extremities.

Narrow chest · Very frequent (99-80%)

Reduced width of the chest from side to side, associated with a reduced distance from the sternal notch to the tip of the shoulder.

Platyspondyly · Very frequent (99-80%)

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

Short palm · Very frequent (99-80%)

Short palm.

Short stature · Very frequent (99-80%)

A height below that which is expected according to age and gender norms. Although there is no universally accepted definition of short stature, many refer to "short stature" as height more than 2 standard deviations below the mean for age and gender (or below the 3rd percentile for age and gender dependent norms).

Coxa valga · Frequent (79-30%)

Coxa valga is a deformity of the hip in which the angle between the femoral shaft and the femoral neck is increased compared to age-adjusted values (about 150 degrees in newborns gradually reducing to 120-130 degrees in adults).

Delayed eruption of teeth · Frequent (79-30%)

Delayed tooth eruption, which can be defined as tooth eruption more than 2 SD beyond the mean eruption age.

Scoliosis · Frequent (79-30%)

The presence of an abnormal lateral curvature of the spine.

Square pelvis · Frequent (79-30%)

An abnormally squared appearance of the bony pelvis, a normally rounded or basin-shaped structure.

Bowing of the long bones · Occasional (29-5%)

A bending or abnormal curvature of a long bone.

Other findings in the same source

From: Orphanet

Additional reported features include Death in infancy (Occasional (29-5%)); Depressed nasal bridge (Occasional (29-5%)); Frontal bossing (Occasional (29-5%)); Patent ductus arteriosus (Occasional (29-5%)); Respiratory distress (Occasional (29-5%)); Retrognathia (Occasional (29-5%)); Short nose (Occasional (29-5%)); Strabismus (Occasional (29-5%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

Infancy; Neonatal

Inheritance in the source

From: Orphanet

Autosomal recessive

Frequency and the population described

From: Orphanet

Reported case(s): 11.0; 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 recessive pattern usually involves disease-causing changes in both copies of a gene. Parents may each carry one altered copy without having the condition themselves. A genetic counsellor can explain carrier testing and reproductive implications using the actual laboratory findings, rather than the condition name alone.

Which doctor should you see?

The suggested department for discussing Odontochondrodysplasia 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 Odontochondrodysplasia. 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.