Cryptorchidism, or failure of testicular descent, is a common human congenital abnormality with a multifactorial etiology that likely reflects the involvement of endocrine, environmental, and hereditary factors. Cryptorchidism can result in infertility and increases risk for testicular tumors. Testicular descent from abdomen to scrotum occurs in 2 distinct phases: the transabdominal phase and the inguinoscrotal phase (summary by Gorlov et al., 2002).

Aplasia of the uterus.

Apparently small scrotum for age.

Abnormal position of urethral meatus on the ventral penile shaft (underside) characterized by displacement of the urethral meatus from the tip of the glans penis to the ventral surface of the penis, scrotum, or perineum.

Underdevelopment of the radius.

Absence of the fibula.

Aplasia or Hypoplasia affecting the metacarpal bones.

Congenital absence of a carpal bone.

Small or missing phalangeal bones of the fingers of the hand.

Absence or underdevelopment of the tarsal bones.

A measured foot length that is more than 2 SD below the mean for a newborn of 27 - 41 weeks gestation, or foot that is less than the 3rd centile for individuals from birth to 16 years of age (objective). Alternatively, a foot that appears disproportionately short (subjective).

Absence or underdevelopment of the femur.

A bending or abnormal curvature of the radius.

Absence or underdevelopment of the metatarsal bones.

Missing ulna bone associated with congenital failure of development.

A condition in which middle parts of the hand (fingers and metacarpals) are missing giving a cleft appearance. The severity is very variable ranging from slightly hypoplastic middle fingers over absent middle fingers as far as oligo- or monodactyl hands.

An abnormal osseous union (fusion) between the radius and the humerus.

Absence or underdevelopment of the carpal bones.

A developmental defect resulting in the presence of fewer than the normal number of toes.

Absence (due to failure to form) or underdevelopment of the extremities.

A developmental defect resulting in the presence of fewer than the normal number of fingers (i.e., aplasia of one or more fingers).

A kind of short stature in which different regions of the body are shortened to differing extents.

Upper insertion of the ear to the scalp below an imaginary horizontal line drawn between the inner canthi of the eye and extending posteriorly to the ear.

An abnormality of the pinna, which is also referred to as the auricle or external ear.

Median longitudinal ear length greater than two SD above the mean determined by the maximal distance from the superior aspect to the inferior aspect of the external ear.

A herniation of meninges through a congenital bone defect in the skull in the occipital region.

Displacement of the femur from its normal location in the hip joint.

Missing or malformed long bones of the extremities with the distal parts (such as hands and/or feet) connected to the variably shortened or even absent extremity, leading to a flipper-like appearance, as opposed to other forms of limb malformations were either the hole limb is missing (such as amelia), or the distal part of a limb is absent (peromelia).

A sinus in the coccygeal region (the region of the intergluteal cleft). A pilonidal sinus often contains hair and skin debris.

A deformity of the chest caused by overgrowth of the ribs and characterized by protrusion of the sternum.

A rounded, bulging chest that resembles the shape of a barrel. That is, there is an increased anteroposterior diameter and usually some degree of kyphosis.

The two portions of the clavicle (corresponding to the two primary ossification centers of the clavicle) are connected by a fibrous bridge that is contiguous with the periosteum, and a synovial membrane develops, resulting in a clavicle with a bipartite appearance radiographically. Congenital pseudarthrosis of the clavicle generally presents as a painless mass or swelling over the clavicle.

Absence of one half of the vertebral body.

An elbow contracture that limits the ability of the elbow joint to be extended (straightened), meaning that the elbow is fixed in an flexed (bent) position.

Increased width (cross-sectional diameter) of the clavicles.

Abnormal reduction in ossification of the calvaria (roof of the skull consisting of the frontal bone, parietal bones, temporal bones, and occipital bone).

Increased width of ribs

A developmental defect characterized by lack of development of the pubis bone.

Absence or underdevelopment of the pubic bone.

Bowing (abnormal curvature) of the femur.

Height of the palate more than 2 SD above the mean (objective) or palatal height at the level of the first permanent molar more than twice the height of the teeth (subjective).

Diminished length of the neck.

Epicanthus is a condition in which a fold of skin stretches from the upper to the lower eyelid, partially covering the inner canthus. Usher (1935) noted that epicanthus is a normal finding in the fetus of all races. Epicanthus also occurs in association with hereditary ptosis (110100).

Width of the palate more than 2 SD below the mean (objective) or apparently decreased palatal width (subjective).

Facial height (length) is more than 2 standard deviations above the mean (objective); or, an apparent increase in the height (length) of the face (subjective).

Increased breadth of the nasal bridge (and with it, the nasal root).

Increased side-to-side width of the neck.

Congenital anonychia is defined as the absence of fingernails and toenails. Anonychia and its milder phenotypic variant, hyponychia, usually occur as a feature of genetic syndromes, in association with significant skeletal and limb anomalies. Isolated nonsyndromic congenital anonychia/hyponychia is a rare entity that usually follows autosomal recessive inheritance with variable expression, even within a given family. The nail phenotypes observed range from no nail field to a nail field of reduced size with an absent or rudimentary nail (summary by Bruchle et al., 2008). This form of nail disorder is referred to here as nonsyndromic congenital nail disorder-4 (NDNC4). For a list of other nonsyndromic congenital nail disorders and a discussion of genetic heterogeneity, see NDNC1 (161050).

Underdevelopment of the nipple.