Because collagen plays an important role in the development of the body, people with Kniest Dysplasia will typically have their first symptoms at birth. These symptoms can include:.

- Musculoskeletal Problems

- Short limbs

- Shortened body trunk

- Flattened bones in the spine

- kyphoscoliosis

- Scoliosis (Lateral curvature of the spine)

- Early development of arthritis

- Respiratory problems

- Respiratory tract infection

- Difficulty breathing

- Eye problems

- Severe myopia (near-sightedness)

- Cataract (cloudiness in the lens of the eye)

- Hearing problems

- progressive hearing loss

- ear infections

Most symptoms are chronic and will continue to worsen as the individual ages. It is essential to have regular checkups with general doctors, orthopedist, ophthalmologists, and/or otorhinolaryngologists. This will help to detect whether there are any changes that could cause concern.

People with this condition are short-statured from birth, with a very short trunk and shortened limbs. Their hands and feet, however, are usually average-sized. Curvature of the spine (scoliosis and lumbar lordosis) may be severe and can cause problems with breathing. Changes in the spinal bones (vertebrae) in the neck may also increase the risk of spinal cord damage. Other skeletal signs include flattened vertebrae (platyspondyly), severe protrusion of the breastbone (pectus carinatum), a hip joint deformity in which the upper leg bones turn inward (coxa vara), and a foot deformity known as clubfoot.

Affected individuals have mild and variable changes in their facial features. The cheekbones close to the nose may appear flattened. Some infants are born with an opening in the roof of the mouth, which is called a cleft palate. Severe nearsightedness (high myopia) and detachment of the retina (the part of the eye that detects light and color) are also common.

This condition is a skeletal dysplasia characterized by short stature, mild brachydactyly, kyphoscoliosis, abnormal gait, enlarged knee joints, precocious osteoarthropathy, platyspondyly, delayed epiphyseal ossification, mild metaphyseal abnormalities, short stature and short and bowed legs. Intelligence is normal.

Some patients may manifest premature pubarche and hyperandrogenism.

Other features that may form part of the syndrome include precocious costal calcification, small iliac bones, short femoral necks, coxa vara, short halluces and fused vertebral bodies.

Spondyloepimetaphyseal dysplasia, Strudwick type is an inherited disorder of bone growth that results in dwarfism, characteristic skeletal abnormalities, and problems with vision. The name of the condition indicates that it affects the bones of the spine (spondylo-) and two regions near the ends of bones (epiphyses and metaphyses). This type was named after the first reported patient with the disorder. Spondyloepimetaphyseal dysplasia, Strudwick type is a subtype of collagenopathy, types II and XI.

The signs and symptoms of this condition at birth are very similar to those of spondyloepiphyseal dysplasia congenita, a related skeletal disorder. Beginning in childhood, the two conditions can be distinguished in X-ray images by changes in areas near the ends of bones (metaphyses). These changes are characteristic of spondyloepimetaphyseal dysplasia, Strudwick type.

Kniest Dysplasia is a rare form of dwarfism caused by a mutation in the COL2A1 gene on chromosome 12. The COL2A1 gene is responsible for producing type II collagen. The mutation of COL2A1 gene leads to abnormal skeletal growth and problems with hearing and vision. What characterizes kniest dysplasia from other type II Osteochondrodysplasia is the level of severity and the dumb-bell shape of shortened long tubular bones. This condition was first diagnosed by Dr. Wilhelm Kniest in 1952. Dr. Kniest noticed that his 50 year old patient was having difficulties with restricted joint mobility. The patient had a short stature and was also suffering from blindness. Upon analysis of the patient's DNA, Dr. Kniest discovered that a mutation had occurred at a splice site of the COL2A1 gene. This condition is very rare and occurs less than 1 in 1,000,000 people. Males and females have equal chances of having this condition. Currently, there is no cure for kniest dysplasia. Alternative names for Kniest Dysplasia can include Kniest Syndrome, Swiss Cheese Cartilage Syndrome, Kniest Chondrodystrophy, or Metatrophic Dwarfism Type II.

Children with autosomal dominant MED experience joint pain and fatigue after exercising. Their x-rays show small and irregular ossifications centers, most apparent in the hips and knees. A waddling gait may develop. Flat feet are very common.

The spine is normal but may have a few irregularities, such as scoliosis. There are very small capital femoral epiphyses and hypoplastic, poorly formed acetabular roofs. Knees have metaphyseal widening and irregularity while hands have brachydactyly (short fingers) and proximal metacarpal rounding. By adulthood, people with MED are of short stature or in the low range of normal and have short limbs relative to their trunks. Frequently, movement becomes limited at the major joints, especially at the elbows and hips. However, loose knee and finger joints can occur. Signs of osteoarthritis usually begin in early adulthood.

Children with recessive MED experience joint pain, particularly of the hips and knees, and commonly have deformities of the hands, feet, knees, or vertebral column (like scoliosis). Approximately 50% of affected children have abnormal findings at birth (such as club foot or twisted metatarsals, cleft palate, inward curving fingers due to underdeveloped bones and brachydactyly, or ear swelling caused by injury during birth). Height is in the normal range before puberty. As adults, people with recessive MED are only slightly more diminished in stature, but within the normal range. Lateral knee radiography can show multi-layered patellae.

Disproportionate short stature, deformity of the lower limbs, short fingers, and

ligamentous laxity give pseudoachondroplasia its distinctive features. The average height of adult males with the condition is around 120 centimeters (3 ft, 11 in), while adult females are typically around 116 cm (3ft, 9in). Affected individuals are not noticeably short at birth. Patients with pseudoachondroplasia present with gait abnormalities, lower limb deformity, or a retarded growth rate that characteristically appear at age 2-3 years. Disproportionate short stature is characterized by shortening of proximal limb segments (humeri and femora) also called rhizomelic shortening. Other known clinical features include, genu valgum/varum, brachydactyly (short fingers), supple flexion deformity of the hips, knees, hyperlordosis of lumbar spine, rocker bottom feet and broadening of the metaphyseal ends of long bones especially around the wrists, knees and ankles. Patients with pseudoachondroplasia have normal intelligence and craniofacial features, “Figure 1”, “Figure 2”, “Figure 3”.

Achondroplasia is a genetic disorder that results in dwarfism. The arms and legs are short, while the trunk is typically of normal length. Those affected have an average adult height of for males and for females. Other features include an enlarged head and prominent forehead. Intelligence is generally normal.

Achondroplasia is due to a mutation in the FGFR3 gene. In about 80% of cases this occurs as a new mutation during early development. In the other cases it is inherited from one's parents in an autosomal dominant manner. Those with two effected genes do not typically survive. Diagnosis is generally based on symptoms, but may be supported by genetic testing if uncertain.

Treatments may include support groups and growth hormone therapy. Efforts to treat or prevent complications such as obesity, hydrocephalus, obstructive sleep apnea, middle ear infections, or spinal stenosis may be required. Life expectancy of those affected is about 10 years less than average. The condition affects about 1 in 27,500 people. Rates are higher in Denmark and Latin America. The shortest known adults with the condition is Jyoti Amge at .

Spondyloepimetaphyseal dysplasia, Pakistani type is a form of spondyloepimetaphyseal dysplasia involving "PAPSS2" (also known as "ATPSK2"). The condition is rare.

Schmid metaphyseal chondrodysplasia is a type of chondrodysplasia associated with a deficiency of collagen, type X, alpha 1.

Unlike other "rickets syndromes", affected individuals have normal serum calcium, phosphorus, and urinary amino acid levels. Long bones are short and curved, with widened growth plates and metaphyses.

It is named for the German researcher F. Schmid, who characterized it in 1949.

A skeletal survey is useful to confirm the diagnosis of achondroplasia. The skull is large, with a narrow foramen magnum, and relatively small skull base. The vertebral bodies are short and flattened with relatively large intervertebral disk height, and there is congenitally narrowed spinal canal. The iliac wings are small and squared, with a narrow sciatic notch and horizontal acetabular roof. The tubular bones are short and thick with metaphyseal cupping and flaring and irregular growth plates. Fibular overgrowth is present. The hand is broad with short metacarpals and phalanges, and a trident configuration. The ribs are short with cupped anterior ends. If the radiographic features are not classic, a search for a different diagnosis should be entertained. Because of the extremely deformed bone structure, people with achondroplasia are often "double jointed".

The diagnosis can be made by fetal ultrasound by progressive discordance between the femur length and biparietal diameter by age. The trident hand configuration can be seen if the fingers are fully extended."

Another distinct characteristic of the syndrome is thoracolumbar gibbus in infancy.

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 by a drop of linear growth in contrast to peers, a curious, waddling gait or arising lower limb deformities.

Pseudoachondroplasia (also known as PSACH, Pseudoachondroplastic dysplasia, and Pseudoachondroplastic spondyloepiphyseal dysplasia syndrome) is an osteochondrodysplasia that results in mild to severely short stature due to the inhibition of skeletal growth primarily in the limbs. Though similarities in nomenclature may cause confusion, Pseudoachondroplasia should not be confused with achondroplasia, which is a clinically and genetically distinct skeletal dysplasia. Pseudoachondroplasia is caused by a heterozygous mutation in the gene encoding cartilage oligomeric matrix protein COMP. Mutation in the COMP gene can also multiple epiphyseal dysplasia. Despite the radioclinical similarities between pseudoachondroplasia and multiple epiphyseal dysplasia, the latter is less severe.132400

Hematologic manifestations related to bone marrow suppression and subsequent pancytopenia are a major source of morbidity and mortality. Additionally extramedullary hematopoiesis can result in liver and spleen dysfunction. Cranial nerve dysfunction and neurologic complications are usually associated with infantile osteopetrosis. Expansion of the skull bone leads to macrocephaly. Additionally, linear growth retardation that is not apparent at birth, delayed motor milestones and poor dentition can occur.

Fairbank's disease or multiple epiphyseal dysplasia (MED) is a rare genetic disorder (dominant form: 1 in 10,000 births) that affects the growing ends of bones. Long bones normally elongate by expansion of cartilage in the growth plate (epiphyseal plate) near their ends. As it expands outward from the growth plate, the cartilage mineralizes and hardens to become bone (ossification). In MED, this process is defective.

Malignant infantile osteopetrosis, also known as infantile autosomal recessive osteopetrosis or simply infantile osteopetrosis is a rare osteosclerosing type of skeletal dysplasia that typically presents in infancy and is characterized by a unique radiographic appearance of generalized hyperostosis - excessive growth of bone.

The generalized increase in bone density has a special predilection to involve the medullary portion with relative sparing of the cortices. Obliteration of bone marrow spaces and subsequent depression of the cellular function can result in serious hematologic complications. Optic atrophy and cranial nerve damage secondary to bony expansion can result in marked morbidity. The prognosis is extremely poor in untreated cases. Plain radiography provides the key information to the diagnosis. Clinical and radiologic correlations are also fundamental to the diagnostic process, with additional gene testing being confirmatory.

People who are affected by Liebenberg Syndrome suffer from three main symptoms:

1. Dysplasia (improper formation) of the bony components of the elbow

2. Abnormal shape of carpal bones

3. Brachydactyly, a symptom where the fingers and toes are shorter than normal.

The cranium consists of three main sections including the base of the cranium (occipital bone), the face (frontal bone), and the top (parietal bones) and sides (temporal bone) of the head. Most of the bones of the cranium are permanently set into place prior to birth. However, the temporal and parietal bones are separated by sutures, which remain open, allowing the head to slightly change in shape during childbirth. The cranial sutures eventually close within the first couple of years following birth, after the brain has finished growing.

In individuals with SCS, the coronal suture separating the frontal bones from the parietal bones, closes prematurely (craniosynostosis), occasionally even before birth. If the coronal suture closes asymmetrically or unilaterally, then the face and forehead will form unevenly, from side-to-side. People with SCS have pointy, tower-like heads because their brain is growing faster than their skull, resulting in increased intracranial pressure (ICP) and causing the top of the head and/or forehead to bulge out to allow for brain growth. The face appears uneven, particularly in the areas of the eyes and cheeks, and the forehead appears wide and tall.

Because of the abnormal forehead, there is less space for the normal facial features to develop. This results in shallow eye sockets and flat cheekbones. The shallow eye sockets make the eyes more prominent or bulging and cause the eyes to be more separated than normal (hypertelorism). The underdeveloped eye sockets, cheekbones, and lower jaw cause the face to appear flat. Furthermore, the minor downward slant of the eyes along with the drooping eyelids (ptosis) adds to the overall unevenness of the face.

Carpenter syndrome presents several features:

- Tower-shaped skull (craniosynostosis)

- Additional or fused digits (fingers and toes)

- Obesity

- Reduced height

Intellectual disability is also common with the disorder, although some patients may have average intellectual capacity.

Many of the characteristic facial features result from the premature fusion of the skull bones (craniosynostosis). The head is unable to grow normally, which leads to a high prominent forehead (turribrachycephaly), and eyes that appear to bulge (proptosis) and are wide-set (hypertelorism). In addition, there is an underdeveloped upper jaw (maxillary hypoplasia). About 50 percent of children with Pfeiffer syndrome have hearing loss, and dental problems are also common.

In people with Pfeiffer syndrome, the thumbs and first (big) toes are wide and bend away from the other digits (pollex varus and hallux varus). Unusually short fingers and toes (brachydactyly) are also common, and there may be some webbing or fusion between the digits (syndactyly).

Brachydactyly (Greek βραχύς = "short" plus δάκτυλος = "finger"), is a medical term which literally means "shortness of the fingers and toes" (digits). The shortness is relative to the length of other long bones and other parts of the body. Brachydactyly is an inherited, usually dominant trait. It most often occurs as an isolated dysmelia, but can also occur with other anomalies as part of many congenital syndromes.

Nomograms for normal values of finger length as a ratio to other body measurements have been published. In clinical genetics the most commonly used index of digit length is the dimensionless ratio of the length of the 3rd (middle) finger to the hand length. Both are expressed in the same units (centimeters, for example) and are measured in an open hand from the fingertip to the principal creases where the finger joins the palm and where the palm joins the wrist.

Osteopathia striata, also known as Voorhoeve disease, is a rare entity characterized by fine linear striations about 2- to 3-mm-thick, visible by radiographic examination, in the metaphyses and diaphyses of long or flat bones. It is often asymptomatic, and is often discovered incidentally.

In the above brachydactyly syndromes, short digits are the most prominent of the anomalies, but in many other syndromes (Down syndrome, Rubinstein-Taybi syndrome, etc.), brachydactyly is a minor feature compared to the other anomalies or problems comprising the syndrome.

Hidrotic ectodermal dysplasia 2, or Clouston syndrome (referred to as HED2 throughout this entry) is characterized by partial or total alopecia, dystrophy of the nails, hyperpigmentation of the skin (especially over the joints), and clubbing of the fingers. Sparse scalp hair and dysplastic nails are seen early in life. In infancy, scalp hair is wiry, brittle, patchy, and pale; progressive hair loss may lead to total alopecia by puberty. The nails may be milky white in early childhood; they gradually become dystrophic, thick, and distally separated from the nail bed. Palmoplantar keratoderma may develop during childhood and increases in severity with age. The clinical manifestations are highly variable even within the same family.

Liebenberg Syndrome is a rare autosomal genetic disease that involves a deletion mutation upstream of the PITX1 gene, which is one that's responsible for the body's organization, specifically in forming lower limbs. In animal studies, when this deletion was introduced to developing birds, their wing buds were noted to take on limb-like structures.

The condition was first described by Dr. F. Liebenberg in 1973 while he followed multiple generations of a South African family, but it has since been noticed in other family lineages across the world.

Carpenter Syndrome belongs to a group of rare genetic disorders known as acrocephalopolysyndactyly, abbreviated ACPS (RN, 2007). There were originally five types of ACPS, but this number has been decreased because they have been found to be closely related to one another or to other disorders (Paul A. Johnson, 2002).

The most common physical manifestation of Carpenter Syndrome is early fusing of the fibrous cranial sutures which results in an abnormally pointed head. The fusion of the skull bones is evident from birth (National Organization for Rare Disorders, Inc., 2008). Babies’ mobile cranial bones form a cone shape as the pass through the birth canal and soon thereafter return to a normal shape; however, a baby affected by carpenter syndrome maintains a cone shaped head.

A baby affected by Carpenter Syndrome will also display malformations of the face. An individual affected by the syndrome may have broad cheeks, a flat nasal bridge, and a wide upturned nose with abnormally large nasal openings. Their ears will most commonly be low, unevenly set, and malformed in structure. In addition to these facial abnormalities, individuals also have an underdeveloped maxilla and/ or mandible with a highly arched and narrow palate which makes speech a very difficult skill to master. Teeth are usually very late to come in and will be undersized and spaced far apart (Carpenter Syndrome-description).

Other physical abnormalities often associated with Carpenter Syndrome include extra digits. Extra toes are more commonly seen than fingers. Often both the toes and fingers are webbed, a process that occurs before the sixth week gestational period. Often their digits will be abnormally short, and the fingers are commonly missing an interphalangeal joint. Roughly half of the babies born with Carpenter Syndrome have some type of heart defect, and seventy five percent of individuals with this disease will experience some degree of development delay due to mild mental retardation (Carpenter Syndrome-description).