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.

Pacman dysplasia (alternatively known as epiphyseal stippling with osteoclastic hyperplasia) is a lethal autosomal recessive skeletal dysplasia. The dysplasia is present during fetal development.

Gerodermia osteodysplastica is characterized by symptoms and features which affect the connective tissues, skin and skeletal system.

These are: wrinkly, loose skin over the face, abdomen, and extremites (hands, feet) on the dorsal sides usually worsened by chronic joint laxity and hyperextensibility; fragmented elastic fibers of the skin that are reduced in number, with disorientation of collagen fibers; osteopenia and osteoporosis, with associated fractures; malar hypoplasia (underdeveloped cheek bone), maxillary hypoplasia (underdeveloped upper jaw), mandibular prognathism (protrusion of the lower jaw and chin), bowed long bones, platyspondyly (flattened spine) related to vertebral collapse; kyphoscoliosis (scoliosis with kyphosis, or "hunch back"), metaphyseal peg (an unusual outgrowth of metaphyseal tissue which protrudes into the epiphyseal region of the bone, near the knee); and the overall physical effects and facial appearance of dwarfism with premature aging.

Other features and findings include: intrauterine growth retardation, congenital hip dislocations, winged scapulae (shoulder blades), pes planus (fallen arches), pseudoepiphyses of the second metacarpals (upper bone of the fingers), hypotelorism (close-set eyes), malformed ears,

developmental delay,

failure to thrive and abnormal electroencephalograph (EEG) readings.

Dental and orthodontal abnormalities in addition to maxillary hypoplasia and mandibular prognathism have also been observed in gerodermia osteodysplastica. Including malocclusion of the dental arches (the maxilla and mandible), radiological findings in some cases have indicated significant overgrowth of the mandibular premolar and molar roots;

hypercementosis (overproduction of cementum) of the molars and maxillary incisors; enlarged, funnel-shaped mandibular lingula (spiny structures on the ramus of the mandible); and a radiolucent effect on portions of many teeth, increasing their transparency to x-rays.

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

The appearance of people with the disorder is caused by a loss of bone in the mandible which the body replaces with excessive amounts of fibrous tissue. In most cases, the condition fades as the child grows, but in a few even rarer cases the condition continues to deform the affected person's face. Cherubism also causes premature loss of the primary teeth and uneruption of the permanent teeth.

The condition Cherubism is a rare autosomal dominant disease of the maxilla and mandible. Approximately 200 cases have been reported by medical journals with the majority being males. Cherubism is usually first diagnosed around age 7 and continues through puberty and may or may not continue to advance with age. The degrees of Cherubism vary from mild to severe. Osteoclastic and osteoblastic remodeling contributes to the change of normal bone to fibrous tissue and cyst formation. As noted by the name, the patient's face becomes enlarged and disproportionate due to the fibrous tissue and atypical bone formation. The sponge-like bone formations lead to early tooth loss and permanent tooth eruption problems. The condition also affects the orbital area, creating an upturned eye appearance. The cause of cherubism is believed to be traced to a genetic defect resulting from a mutation of the SH3BP2 gene from chromosome 4p16.3. While the condition is rare and painless, the afflicted suffer the emotional trauma of disfigurement. The effects of Cherubism may also interfere with normal jaw motion and speech. Currently, removal of the tissue and bone by surgery is the only treatment available. This condition is also one of the few that unexpectedly stops and regresses. Normal bone remodeling activity may resume after puberty.

Cherubism is displayed with genetic conformation and when excessive osteoclasts are found in the affected areas of the mandible and maxilla. Large cysts will be present with excessive fibrous areas inside the bone. The fibers and cysts will be found among the trabecula of the Coronoid process, the ramus of mandible, the body of mandible and the maxilla regions. The maxilla will be affected up to and including the orbits and sometimes inside the lower orbits. The maxilla and zygomatic bones are depressed and eyes appear to gaze upward. The maxilla has been found to be more severely affected in most cases than the mandible bone. Some patients found with lower inner orbital growths and cysts may lose vision.

Autosomal recessive multiple epiphyseal dysplasia (ARMED), also called epiphyseal dysplasia, multiple, 4 (EDM4), multiple epiphyseal dysplasia with clubfoot or –with bilayered patellae, is an autosomal recessive congenital disorder affecting cartilage and bone development. The disorder has relatively mild signs and symptoms, including joint pain, scoliosis, and malformations of the hands, feet, and knees.

Some affected individuals are born with an inward- and downward-turning foot (a clubfoot). An abnormality of the kneecap called a double-layered patella is also relatively common. Although some people with recessive multiple epiphyseal dysplasia have short stature as adults, most are of normal height. The incidence is unknown as many cases are not diagnosed due to mild symptoms.

Gerodermia osteodysplastica (GO), also called geroderma osteodysplasticum and Walt Disney dwarfism, is a rare autosomal recessive connective tissue disorder included in the spectrum of cutis laxa syndromes.

Usage of the name "Walt Disney dwarfism" is attributed to the first known case of the disorder, documented in a 1950 journal report, in which the authors described five affected members from a Swiss family as having the physical appearance of dwarves from a Walt Disney film.

The terms "geroderma" or "gerodermia" can be used interchangeably with "osteodysplastica" or "osteodysplasticum", with the term "hereditaria" sometimes appearing at the end.

Nominally, the disease consists of multiple enchondromas which usually develop in childhood. The growth of these enchondromas usually stops after skeletal maturation. The affected extremity is shortened (asymmetric dwarfism) and sometimes bowed due to epiphyseal fusion anomalies. Persons with Ollier disease are prone to breaking bones and normally have swollen, aching limbs.

On radiographs, streaks of low density are seen projecting through the diaphyses into the epiphyses of the long bones, due to ectopic cartilage deposits. With age, the cartilage may calcify in the typical "snowflake" pattern.

Cherubism is a rare genetic disorder that causes prominence in the lower portion in the face. The name is derived from the temporary chubby-cheeked resemblance to putti, often confused with cherubs, in Renaissance paintings.

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”.

This condition occurs almost exclusively in males. The mutation may be spontaneous or inherited from the mother. The typical clinical features are:

- flat nasal tip

- short columella

- maxillary hypoplasia

- involvement of terminal phalanges

- stippled chondrodystrophy

Fibrocartilaginous mesenchymoma of bone is (FCMB) is an extremely rare tumor first described in 1984. Fewer than 20 cases have been reported, with patient ages spanning from 9 to 25 years, though a case in a male infant aged 1 year and 7 months has been reported. Quick growth and bulky size are remarkable features of this tumor.

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

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.

X-linked recessive chondrodysplasia punctata is a type of chondrodysplasia punctata that can involve the skin, hair, and cause short stature with skeletal abnormalities, cataracts, and deafness.

This condition is also known as arylsulfatase E deficiency, CDPX1, and X-linked recessive chondrodysplasia punctata 1. The syndrome rarely affects females, but they can be carriers of the recessive allele. Although the exact number of people diagnosed with CDPX1 is unknown, it was estimated that 1 in 500,000 have CDPX1 in varying severity. This condition is not linked to a specific ethnicity. The mutation that leads to a deficiency in arylsulfatase E. (ARSE) occurs in the coding region of the gene.Absence of stippling, deposits of calcium, of bones and cartilage, shown on x-ray, does not rule out chondrodysplasia punctata or a normal chondrodysplasia punctata 1 (CDPX1) gene without mutation. Stippling of the bones and cartilage is rarely seen after childhood. Phalangeal abnormalities are important clinical features to look for once the stippling is no longer visible. Other, more severe, clinical features include respiratory abnormalities, hearing loss, cervical spine abnormalities, delayed cognitive development, ophthalmologic abnormalities, cardiac abnormalities, gastroesophageal reflux, and feeding difficulties. CDPX1 actually has a spectrum of severity; different mutations within the CDPX1 gene have different effects on the catalytic activity of the ARSE protein. The mutations vary between missense, nonsense, insertions, and deletions.

The most common locations are the shaft and epyphises of long bones (fibula and humerus) but the spine, metatarsal bones, and ilium have been involved as well. Radiologic examination evidences osteolytic areas with a lobulated framework comprising radiolucent and radiodense foci admixed to speckled calcification. Cortical destruction is a common finding with no soft tissue expansion in many cases. Histopathology of the lesion shows large areas of mature fibrous stroma undergoing hyaline cartilage metaplasia resulting in conspicuous lobules or gradual transformation into chondroid foci. Both hyaline cartilage and chondroid in turn undergo calcification and endochondral cancellous bone formation mimicking epiphyseal plate-like cartilage.

Differential diagnosis is concerned with fibrocartilaginous dysplasia of bone, desmoplastic fibroma, low-grade fibrosarcoma, chondromyxoid fibroma and low-grade chondrosarcoma.

A full account of imaging findings on radiography, bone scan, CT and magnetic resonance has been provided by Sumner et al.

Symptoms are related to defects in connective tissue.

- Congenital anterior dislocation of the knees

- Dislocation of hips and shoulders

- Flattened facial appearance

- Prominent forehead

- Depressed nasal bridge

- Club foot

- Cervical kyphosis

PDP has a number of visible symptoms. Most important clinical features are: pachydermia (thickening and wrinkling of the skin), furrowing of the face and scalp, periostosis (swelling of periarticular tissue and shaggy periosteal new bone formation of long bones) and digital clubbing (enlargement of fingertips). Other features include excessive sweating, arthralgia and gastrointestinal abnormalities. An overview of all symptoms is provided in table 2.

Table 2. Overview of symptoms

These symptoms were found in rare cases of Larsen syndrome.

- Cataracts

- Cleft palate

- Extra bones of wrist

- Malocclusion

- Microdontia and hypodontia

- Complete agenesis of anus

- uterus

- Bifid tongue

Typically patients present with progressive pain, often long standing and/or bony swelling and restricted range of movement in affected limb 3,12. The latter is most often the case in bones with little overlying soft tissues (e.g. short tubular bones of the hands and feet).

Most chondromyxoid fibromas are located in the metaphyseal region of long bones (60%), and may extend to the epiphyseal line and even rarely abut the articular surface 3,12. They are almost never just epiphyseal 3. The classical site is the upper 1/3rd of tibia ( which accounts for 25% of all cases) with the small tubular bones of the foot, the distal femur and pelvis being other relatively common locations 12.

Rarely occur in the skull or skull base.

Pachydermoperiostosis (PDP) or primary hypertrophic osteoarthropathy (PHO) is a rare genetic disorder that affects both bones and skin. Other names are idiopathic hypertrophic osteoarthropathy or Touraine-Solente-Golé syndrome. It is mainly characterized by pachydermia (thickening of the skin), periostosis (excessive bone formation) and finger clubbing (swelling of tissue with loss of normal angle between nail and nail bed).

This disease affects relatively more men than women. After onset, the disease stabilizes after about 5–20 years. Life of PDP patients can be severely impaired. Currently, symptomatic treatments are NSAIDs and steroids or surgical procedures.

In 1868, PDP was first described by Friedreich as ‘excessive growth of bone of the entire skeleton’. Touraine, Solente and Golé described PDP as the primary form of bone disease hypertrophic osteoarthropathy in 1935 and distinguished its three known forms.

The symptoms of Gorham's disease vary depending on the bones involved. It may affect any part of the skeleton, but the most common sites of disease are the shoulder, skull, pelvic girdle, jaw, ribs, and spine.

In some cases there are no symptoms until a fracture occurs either spontaneously or following minor trauma, such as a fall. There may be an acute onset of localized pain and swelling. More commonly there is pain of no apparent cause that increases in frequency and intensity over time and may eventually be accompanied by weakness and noticeable deformity of the area. The rate of progression is unpredictable and the prognosis can be difficult. The disease may stabilize after a number of years, go into spontaneous remission, or, in cases involving the chest and upper spine, prove fatal. Recurrence of the disease following remission can also occur. Involvement of the spine and skull base may cause a poor outcome from neurological complications. In many cases, the end result of Gorham's disease is severe deformity and functional disability.

Symptoms such as difficulty breathing and chest pain may be present if the disease is present in the ribs, scapula, or thoracic vertebrae. These may indicate that the disease has spread from the bone into the chest cavity. The breathing problems may be misdiagnosed as asthma, because the damage done to the lungs can cause the same types of changes to lung function testing that are seen in asthma. Extension of the lesions into the chest may lead to the development of chylous pleural and pericardial effusions. Chyle is rich in protein and white blood cells that are important in fighting infection. The loss of chyle into the chest can have serious consequences, including infection, malnutrition, and respiratory distress and failure. These complications or their symptoms, such as difficulty breathing, chest pain, poor growth or weight loss, and infection have sometimes been the first indications of the condition.

Chondromyxoid fibroma is a type of cartilaginous tumor.

Most cases are characterised by GRM1 gene fusion or promoter swapping. It can be associated with a translocation at t(1;5)(p13;p13).

A chondromyxoid fibroma (CMF) is an extremely rare benign cartilaginous neoplasm which accounts for < 1% bone tumours.