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Trismus Pseudocamptodactyly Syndrome

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Synonyms of Trismus Pseudocamptodactyly Syndrome

Disorder Subdivisions

General Discussion

Trismus-Pseudocamptodactyly Syndrome is a very rare inherited disorder characterized by the inability to completely open the mouth (trismus), causing difficulty with chewing (mastication) and/or the presence of abnormally short muscle-tendon units in the fingers, causing the fingers to curve or bend (camptodactyly) when the hand is bent back at the wrist (dorsiflexion). Because the fingers are not permanently bent or curved, this particular finding is termed "pseudocamptodactyly" (pseudo meaning false). In addition, the muscle-tendon units of the forearms and/or the legs may also be abnormally short, resulting in limited movements and various deformities of the feet. Individuals with this disorder are slightly shorter than would otherwise be expected (mild short stature). The severity of these physical findings varies from individual to individual. Trismus-Pseudocamptodactyly Syndrome is thought to be inherited as an autosomal dominant trait.


Trismus-Pseudocamptodactyly Syndrome is a very rare inherited disorder characterized the inability to fully open the mouth (trismus), often resulting in problems with chewing (mastication). Although this limitation is one of the significant findings associated with this disorder, it may be quite subtle in some affected individuals. In those whom this abnormality is severe, limited and/or impaired chewing (mastication) ability may cause difficulties with eating and proper digestion.

Other major physical findings associated with Trismus-Pseudocamptodactyly Syndrome involve the fibrous cords that connect muscles to bones (tendons). The tendons work in concert with the respective muscles (muscle-tendon unit) and bones to produce movement of various parts of the body. If tendons are unusually short, certain physical abnormalities may result. In Trismus-Pseudocamptodactyly Syndrome, the muscle-tendon units in the fingers are unusually short, resulting in curved or bent fingers (camptodactyly) when the hand is bent backward at the wrist (dorsiflexion). However, if the hand is bent forward at the wrist (volar flexion), the fingers can then be completely extended. Because the fingers are not permanently fixed in the curved or bent position, this particular abnormality may properly be called "pseudocamptodactyly" (pseudo meaning false).

In addition, individuals with this syndrome have shortened muscle-tendon units in the forearms and legs, the latter possibly resulting in various foot deformities. These may include a permanent flexing of the toe or toes (hammer or claw toes), abnormal inward bending of the foot (clubfoot or talipes), flatfoot (pes planus), and/or pigeon-toe (metatarsus varus). In some cases, shortened muscles and tendons may result in an unusual tilt of the pelvis and/or an abnormal positioning or slight twist of the head (mild torticollis). In addition, affected individuals may exhibit difficulty in manual dexterity and walking (locomotion) due to shortened muscle-tendon units and associated abnormalities.

In some cases, individuals with Trismus-Pseudocamptodactyly Syndrome exhibit additional physical abnormalities. For example, they may be slightly shorter than would otherwise be expected. It is important to note that the severity of many of the physical findings associated with this disorder may vary greatly from individual to individual.


Trismus-Pseudocamptodactyly Syndrome is thought to be inherited as an autosomal dominant trait. Genetic diseases are determined by two genes, one received from the father and one from the mother.

Dominant genetic disorders occur when only a single copy of an abnormal gene is necessary for the appearance of the disease. The abnormal gene can be inherited from either parent, or can be the result of a new mutation (gene change) in the affected individual. The risk of passing the abnormal gene from affected parent to offspring is 50% for each pregnancy regardless of the sex of the resulting child.

Affected Populations

Trismus-Pseudocamptodactyly Syndrome is a very rare inherited disorder that, in theory, affects males and females in equal numbers. However, for unexplained reasons, in reported cases females are affected twice as often as males (F2:M1). Approximately 60 cases have been reported in the medical literature. Of those cases, many have been traced to a Dutch female who came to the United States and settled in Tennessee during the latter half of the eighteenth century. In addition, other reported cases have included five affected individuals in three generations of one Japanese family, six affected members of a German family, and affected individuals of families (kindreds) within the Netherlands, Canada, and, as mentioned above, the United States. The disorder was first described in the medical literature in 1969.

Many of the symptoms of Trismus-Pseudocamptodactyly Syndrome are manifested during infancy. As an affected child ages, abnormalities associated with shortened muscle-tendons units (e.g., difficulty in manual dexterity) may become apparent.

Related Disorders

Symptoms of the following disorders can be similar to those of Trismus-Pseudocamptodactyly Syndrome. Comparisons may be useful for a differential diagnosis:

Freeman-Sheldon Syndrome, (also known as Craniocarpotarsal Dystrophy, Whistling Face Syndrome, or Whistling Face-Windmill Vane Hand Syndrome) is a very rare genetic disorder that is apparent at birth (congenital). It is characterized by abnormal skeletal development and an unusual flat, expressionless face with full cheeks and a small mouth, giving a typical "whistling" facial appearance. Symptoms may include permanent fixation of the fingers in a flexed position (camptodactyly), unusual outward positioning of the fingers (ulnar deviation of the fingers), and/or abnormal inward bending of the foot (clubfoot or talipes). In addition, affected individuals may exhibit deep set and widely-spaced eyes, small nose and nostrils, small mouth, vertical folds in the jaw skin, and/or other aberrations of the face. In some cases, side-to-side curvature of the spine (scoliosis) may be present. Other skeletal malformations may become apparent during X-ray or other imaging procedures. Individuals with Freeman Sheldon Syndrome are of normal height. This syndrome is inherited as an autosomal dominant genetic trait, although some researchers believe that it may be inherited in a recessive form. (For more information on this disorder, choose "Freeman Sheldon" as your search term in the Rare Disease Database.)

Distal Arthrogryposis Multiplex Congenita, Type II is a very rare inherited disorder that is apparent at birth and is characterized by stiffness or immobility of the joints (contractures) with deformities of the hands and/or feet. Symptoms may include a permanent flexing of the fingers (camptodactyly), unusual positioning of the fingers and/or feet, abnormal bending inward of the foot (clubfoot), and other irregularities of the arms and legs. Other features of this disorder may include an inability to completely open the mouth (trismus), an underdeveloped jaw (micrognathia), a receding jaw (retrognathia), an abnormal groove (cleft) on the upper lip and/or incomplete closure of the roof of the mouth (palate), droopy eyelids (ptosis), and/or a webbed neck. In addition, affected individuals may exhibit abnormalities of the bones of the spine (vertebrae). People with Distal Arthrogryposis Multiplex Congenita, Type II are shorter than would otherwise be expected. This disorder is thought to be inherited as an autosomal dominant genetic trait. (For more information on this disorder, choose "Arthrogryposis Multiplex Congenita" as your search term in the Rare Disease Database.)

Standard Therapies

Trismus-Pseudocamptodactyly Syndrome may be diagnosed during infancy, based upon a thorough clinical evaluation, characteristic physical findings, and/or a variety of specialized tests, including X-rays studies.

The treatment of this disorder is directed toward the specific symptoms exhibited in each individual. Treatment may require the efforts of a team of specialists who work together to systematically and comprehensively plan an affected child's treatment. Such specialists may include pediatricians, those who diagnose and treat skeletal disorders (orthopedists), orthopedic surgeons, dentists, anesthesiologists, physicians who specialize in disorders of the digestive tract (gastroenterologists), nutritionists, physical and occupational therapists, and/or other health care professionals.

Specific therapies for the treatment of this disorder are symptomatic and supportive. For example, in some cases, various orthopedic techniques and/or surgery may be performed to treat and/or correct certain musculoskeletal abnormalities associated with Trismus-Pseudocamptodactyly Syndrome.

In addition, physical and/or occupational therapy may be beneficial to those individuals who experience difficulties with walking (locomotion) and manual dexterity.

Genetic counseling will also be of benefit for affected individuals and their families.

Investigational Therapies

Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government web site.

For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:

Tollfree: (800) 411-1222
TTY: (866) 411-1010
Email: prpl@cc.nih.gov

For information about clinical trials sponsored by private sources, contact:

Trismus Pseudocamptodactyly Syndrome Resources

(Please note that some of these organizations may provide information concerning certain conditions potentially associated with this disorder [e.g., musculoskeletal abnormalities, etc.].)



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Report last updated: 2008/04/18 00:00:00 GMT+0