The medical term brachydactyly describes shortened fingers and toes. This condition, usually inherited in an autosomal dominant manner, belongs to the group of malformed limbs.
What is brachydactyly?
This genetic defect occurs either in isolation or syndromically. The course may have a primary or a secondary cause. It is additionally characterized by bony dysostosis. Only type A3 and D occur more frequently. The other brachydactyly types are a rare phenomenon. The patient has one or more fingers that are shortened to varying degrees. Nevertheless, physicians also include malformed and shortened toes under this term. In some cases, the metacarpal bones are also affected. This medical term goes back to the ancient Greek language and means “short finger“. Synonyms include brachymegalodactylism, brachyphalangia, and ossificatio praecox hereditaria.
Causes
Brachydactyly is a malformation that occurs by inheritance within a family. A special form of ossificatio praecox hereditaria is the autosomal dominant form of inheritance. However, short stature rarely occurs. The probability of humans being affected is 1:200,000, with exceptions being type A3 and D. Brachydactyly has either an isolated or syndromic expression. In the first case, the hereditary disease is present without any other associated symptoms, whereas in the second case it is due to a complex course of malformation syndrome. Some identifiable courses occur in combination with short stature. Even in the case of isolated brachydactyly, the finding is not simple, since it may be accompanied by subtle changes in other areas of the organism. Other possible manifestations are hand malformations such as polydactyly, syndactyly, symphalangism or reduction defects. Research has now progressed to the point where identification of the causally involved gene is possible for most isolated and sydromal courses. In most cases, isolated brachyphalangia is inherited in an autosomal dominant manner with varying penetrance and expressivity.
Symptoms, complaints, and signs
This malformation occurs in eleven forms and is divided into types according to the expression of the shortening: A1 (Farabee), A2 (Mohr-Wriedt), A3 (brachymesophalangia V), A4 (Temtamy), A5, A6 (Osebold-Remodini syndrome), A7 (brachydactyly Smorgasbord), B, C (Haws), D, E. Types B and E may occur in combination. A joint occurrence of type A1 and B is also possible. Brachydactyly appears in various shapes and forms. Most patients show a laterally symmetrical short finger. Sometimes entire phalanges are missing. Physicians differentiate this malformation according to certain characteristics, for example, whether only the fingers or the toes are affected, or whether malformations of other organs are also present. This distinction is made because brachydactyly is either primary or secondary. In the primary, isolated course of the disease, there is only a malformation of the fingers or toes, without the influence of other clinical pictures. In the secondary, syndromal course, the shortenings are a consequence of certain pre-existing conditions, such as Aarskog-Scott syndrome (malformation of male reproductive organs, anomalies of the face and fingers), a hereditary disease that rarely occurs. In this case, brachydactyly is a secondary consequence of the first disease. The most common form of progression is type D. The last thumb phalanx as well as the fingernail are shortened. Most often, this shortening of the thumb occurs on both hands. In many cases, the big toe is affected as well.
Diagnosis and progression
Diagnosis is made by radiographic and clinical examination. In addition, the findings are supported by anthropometric measurements. If the isolated form of brachydactyly is present, there is no need for prenatal diagnosis. If a syndromal form is present, this form of screening is indicated. In this case, if a causative mutation is present, molecular prenatal diagnosis by chorionic villi (invasive prenatal biopsy) is possible at week 11 and amniocentesis (the amniotic sac is punctured to obtain aminocytes for diagnosis) at week 14. Genetic counseling includes the type of disease that runs in the family.The physician advises the parents-to-be about the type of inheritance and the absence or presence of other symptoms. The probability of developing brachydactyly type D ranges from 0.41 to 4.0 percent. This percentage is population dependent. Sixty-two percent of males affected have reduced penetrance. This means that there is a reduced expression of the genetic defect. The phenotype (appearance) of this inherited disease simply has a reduced set of the traits that lead to the disease.
Complications
Brachydactyly can usually occur in different forms, leading to different complications. The patient suffers from short fingers. However, it also happens that complete fingers are missing. In addition to the fingers, brachydactyly can also negatively affect other organs in the body and lead to malformations or defects in them. In most cases, however, only the missing or malformed fingers occur and there are no other physical limitations or complications. Brachydactyly can also cause malformations to form on the penis. In these cases, the patient’s self-esteem is often diminished. Also, those affected suffer physically and psychologically from the short fingers. In brachydactyly, it is not possible to usually cope with everyday life. Sexual experience is also limited in men, which can lead to depression and other psychological problems. Brachydactyly does not result in a reduced life expectancy. Direct treatment is not possible, but cosmetic surgery can be performed if desired by the patient. In this case, there are also no complications. In severe cases, the function of the hand must be supported and treated during physiotherapy.
When should one go to the doctor?
In most cases, brachydactyly does not need to be additionally diagnosed by a doctor. This complaint is already visible immediately after birth and is detected by the pediatrician. Usually, no treatment of brachydactyly can be performed either. However, since brachydactyly can lead to severe limitations and discomfort in the everyday life of the affected person, a doctor should always be consulted when there are disturbances in the development of children. This can prevent further complications and difficulties in adulthood. A doctor should also be consulted in case of psychological complaints or inferiority complexes in order to avoid depression, for example. Most patients are also dependent on psychological treatment due to brachydactyly, which takes place with a psychologist. The disease itself is diagnosed by the pediatrician. Physiotherapy can limit the individual complaints. Here, the doctor should be visited at an early age, so that the affected person gets used to the restrictions and learns to deal with them properly.
Treatment and therapy
A classical therapy in the medical sense is not possible for brachydactyly. There is no specific form of treatment that can correct all manifestations of this deformity. Plastic surgery is indicated only for cosmetic reasons or when hand function is severely limited. In the presence of the typical forms, surgical interventions are not necessary, since those affected can normally live with shortened fingers or toes without discomfort. Occupational therapy or physical therapy can help strengthen hand function and reduce the effects of shortening. The prognosis of the different types of brachydactyly depends on the type and severity, ranging from severe to minimal impairment. If a syndromic expression of shortening is present, the diagnosis and prognosis are determined by the accompanying abnormalities.
Outlook and prognosis
Without medical care, brachydactyly has no chance of cure. The shortening or absence of bones in the hands and feet is genetic and persists until the end of life. Therapeutic measures or a form of treatment with medication are also unsuccessful. For legal reasons, no intervention is allowed in the genetics of the human being, and targeted training sessions cannot achieve any changes in bone structure. Surgical interventions, on the other hand, are very promising and can lead to complete freedom from symptoms. This depends on the extent of the deformed bones.To achieve the best possible result, the procedure should be performed after the completion of the growth process. Before the end of physical growth, the possibilities of correction are usually not permanent. Other interventions follow in the course of life, which increase the risk of complications. In one operation, lengthening of bones and also complete replacement of missing bones can be performed. In many cases, the patient is considered cured afterwards. Other patients still need to undergo therapies such as physiotherapy to learn how to best handle and move the altered limbs.
Prevention
There is no way to prevent this deformity in the medical sense. Malnutrition or malnutrition, nicotine and alcohol during pregnancy, and a generally unhealthy lifestyle can promote deformities. Drugs and medications taken on one’s own responsibility aggravate the situation. Conversely, this means a healthy and conscious lifestyle favors healthy development.
Here’s what you can do yourself
So far, there are neither conventional nor alternative methods to treat brachydactyly causally. However, those affected do not usually suffer from severe pain or other primarily physical disorders. For many patients, however, brachydactyly is associated with a considerable reduction in quality of life for psychological reasons. Patients with shortened or missing toes often avoid all situations in which they have to show their feet unclothed. They regard water sports and swimming vacations as a taboo. If those affected suffer considerably mentally or limit themselves severely, they should consider the possibility of cosmetic surgery and seek advice from a plastic surgeon who specializes in aesthetic surgery on hands and feet. Those affected must pay for purely cosmetic surgery themselves. However, if a person suffers from brachydactyly also emotionally, the health insurance companies usually cover the costs. In any case, those affected should discuss this in advance with their health insurer. If cosmetic surgery is ruled out, those affected can learn to cope better with their impairment and reduce complexes within the framework of psychotherapy. Very often, one’s own physical deficit is perceived completely exaggerated and out of proportion to the actual disability. If brachydactyly is associated not only with aesthetic but also with functional limitations, physiotherapy is also helpful.
