Rhizomelia refers to either a disproportion of the length of the proximal limb, such as the shortened limbs of
achondroplasia
Achondroplasia is a genetic disorder with an autosomal dominant pattern of inheritance whose primary feature is dwarfism. In those with the condition, the arms and legs are short, while the torso is typically of normal length. Those affected ha ...
, or some other disorder of the hip or shoulder.
According to Stedman's medical dictionary "rhizomelic" means "relating to hip or shoulder joints", while "micromelic" means "having disproportionately short or small limbs".
Genetic skeletal dysplasias or
Osteochondrodysplasia
Osteochondrodysplasia is a general term for a disorder of the development (dysplasia) of bone ("osteo") and cartilage ("chondro"). Osteochondrodysplasias are rare diseases. About 1 in 5,000 babies are born with some type of skeletal dysplasia. Non ...
frequently lead to short stature, occasionally termed dwarfism, which is classified into proportionate and disproportionate short stature. Disproportionate short stature is further classified short-limb short stature and short-trunk short stature. In turn, short-limb short stature is classified into a) Rhizomelic, b) mesomelic and c) acromelic short stature. Rhizomelic short stature refers to skeletal dysplasias where the main shortening is due to involvement of the proximal limb segments i.e. femora and humeri. Typical examples of Rhizomelic short stature are
achondroplasia
Achondroplasia is a genetic disorder with an autosomal dominant pattern of inheritance whose primary feature is dwarfism. In those with the condition, the arms and legs are short, while the torso is typically of normal length. Those affected ha ...
and
pseudoachondroplasia
Pseudoachondroplasia is an inherited disorder of bone growth. It is a genetic autosomal dominant disorder. It is generally not discovered until 2–3 years of age, since growth is normal at first. Pseudoachondroplasia is usually first detected ...
.
See also
*
Amelia (birth defect)
Amelia is the birth defect of lacking one or more limbs. It can also result in a shrunken or deformed limb. The term may be modified to indicate the number of legs or arms missing at birth, such as tetra-amelia for the absence of all four limbs ...
*
Rhizomelic chondrodysplasia punctata
Rhizomelic chondrodysplasia punctata is a rare developmental brain disorder characterized by systemic shortening of the proximal bones (i.e. rhizomelia), seizures, recurrent respiratory tract infections and congenital cataracts. The affected indivi ...
References
External links
Photo (click on link under "Pattern of Shortening")
Congenital disorders of musculoskeletal system
{{musculoskeletal-disease-stub