Four-finger furrow is a hand line of the palm that often occurs in individuals with some form of trisomy. The presence of a four-finger furrow has no pathologic value in and of itself, as the hand line does not affect hand function. For this reason, four-finger furrows do not require specific treatment in either healthy individuals or trisiomy patients.
What is a four-finger furrow?
The palm has different hand lines, which are also called hand furrows. There is a widespread belief in alternative medicine that diseases and dispositions can be read from the hand furrows. In fact, there is a kind of scientifically based palm reading. The palm lines really do reveal something about possible diseases under certain circumstances, such as rare hand furrows like the four-finger furrow. The transverse palmar crease, as it is also called, is a flexion crease located on the palm of the hand with a perpendicular course to the longitudinal axes of the fingers and a parallel course to the metacarpophalangeal joints. The furrow extends from the index finger to the little finger and can be symptomatic of various diseases. However, the four-finger furrow is not always an indication of disease. In the normal population, the furrow occurs on at least one in 100 people. The term four-finger furrow has replaced that of monkey furrow or blocking line. Monkey furrow refers to the context that higher order primates often carry such a furrow.
Causes
Furrows in the palms of the hands are possessed by all humans. In most cases, they are rounded furrows that run in individually curved arcs. The four-finger furrow is not common in the normal population and is considered more of an anomaly than a norm. Possible causes of the line include different trisomies. While the four-finger furrow occurs in only one in a hundred healthy people, it is present in 75 percent of all people with trisomies. Trisomies are triplications of chromosomes or chromosomal segments, such as those characterizing Down syndrome, Pätau syndrome, Edwards syndrome, trisomy 16, trisomy 8, as well as Zellweger syndrome, Aarskog-Scott syndrome, C-trigonocephaly syndrome, Noonan syndrome and Smith-Magenis syndrome. Patients with Wolf-Hirschhorn syndrome, Smith-Lemli-Opitz syndrome, De-Grouchy syndrome, and Schinzel-Giedion syndrome, as well as catcry syndrome, also carry the furrow more frequently than individuals without chromosomal features. Accordingly, a chromosomal abnormality may indeed be the cause of the phenomenon. However, there is no compelling pathologic link.
Symptoms, complaints, and signs
In principle, the four-finger groove is not an impairment. The mobility and function of the affected hand are fully preserved. The only clinical relevance of the furrow is due to the possible context of chromosomal disease. If the four-finger furrow actually occurs in the context of a chromosomal aberration, a single furrow of the fifth finger is usually present in addition to the furrow. Both furrows together suggest the suspicion of a pathological peculiarity. The four-finger furrow alone has no pathologic value in itself. Even the simultaneous presence of a four-finger furrow and a hand furrow on the fifth finger does not automatically confirm a pathological basis. Only in the case of manifest clinical symptoms of the patient, the peculiarities of the palms allow to speculate about a trisomy. The symptoms present in trisomy depend on the length and type of the triplicated chromosomal segment. In most cases, chromosomal abnormalities of this type present with different malformations of tissues or organs that can vary significantly in severity.
Diagnosis and course of the disease
The presence of a four-finger furrow does not necessarily have diagnostic value. Because the furrow can also occur in perfectly healthy individuals, a chromsomal abnormality should not be inferred on the basis of a four-finger furrow alone. Trisomies are usually diagnosed on the basis of characteristic symptoms, organ-specific diagnostics, and molecular genetic analysis. Abnormal hand drawings such as the four-finger furrow can be identified by visual diagnosis and can be included in the case description if a trisomy has already been diagnosed.The prognosis for patients with trisomy depends on the type and length of the triplicated chromosomal segment. If the four-finger furrow is present independently of trisomies, it does not affect hand function or patient health.
Complications
Four-finger furrow does not necessarily cause complications or discomfort in every case. The condition can also occur completely without discomfort or restriction, allowing the affected person to move their hand without difficulty. However, the repeated occurrence of a four-finger furrow can lead to discomfort during movement and thus to restrictions in everyday life. In many cases, the affected persons also suffer from malformations of the internal organs, so that various examinations are necessary in this case. However, these malformations can be very different, so that a general prediction is not possible. The four-finger furrow can also lead to aesthetic discomfort, so that those affected feel uncomfortable or ashamed of it. In children, the condition may also lead to bullying or teasing, causing depression and other psychological symptoms. The quality of life of the affected person is generally reduced by the four-finger groove. The treatment also depends on the exact symptoms and can limit them. There are also no particular complications. In most cases, the complaints can be alleviated. The life expectancy of the affected person is limited in this disease only when severe malformations of the internal organs have occurred.
When should one go to the doctor?
Four-finger furrow is a visual change in the palm of the human hand. This can be perceived immediately after birth via visual contact. Basically, the hand line does not represent a disease value. It is by no means a disease in its own right. Rather, the four-finger furrow is a symptom of an existing health disorder and may indicate a trisomy. The perception of the visual abnormality should therefore be discussed immediately with a doctor. The affected person himself cannot react naturally, therefore parents should immediately consult a doctor as soon as they notice the peculiarity of the hand line. In most cases, childbirth takes place in an inpatient setting or in the presence of a midwife. Since a comprehensive health examination of the newborn takes place immediately after delivery, under optimal conditions the four-finger groove will be noticed by the medically trained staff during this examination. Further steps are decided in consultation with the parents and medical tests are performed. Therefore, in a large number of cases, there is a need for action only if the optical change in the palm of the hand goes unnoticed during the first examinations after birth. If in the further growth process of the child there are abnormalities or peculiarities of behavior as well as appearance, consultation with a doctor should be sought.
Treatment and therapy
A four-finger furrow alone is not an indication for therapy. Even in the context of trisomies, the four-finger furrow is not treated further because the abnormal hand drawing does not cause motor impairment. However, in the larger context of trisomies, numerous other symptoms occur that mandatorily require therapy. In this case, treatment is based on the type of trisomy and the presenting symptoms. Causal treatments are not yet available for patients with trisomies. Since the cause of the diseases lies in a multiplication of the genetic material, at most advances in gene therapy may open up causal treatment options in the course of the next decades. Up to now, the therapy of trisomy patients has been purely symptomatic. The initial focus is on the correction of organic dysplasia, which is a vital therapeutic step in the context of different trisomies above a certain degree of severity. In addition to invasive measures, conservative medicinal and above all supportive therapy steps are available for the symptomatic treatment of some trisomy symptoms. Only a cure cannot be achieved because of the lack of causal therapy to date.
Prevention
A four-finger furrow cannot be prevented.In principle, prevention is also not necessary, since the anomaly as a singular phenomenon has no disease value. To prevent trisomies, genetic counseling may be useful in the family planning phase.
Follow-up
In general, the four-finger groove does not require treatment. Accordingly, follow-up care is not necessary. In patients suffering from hereditary diseases such as Zellweger syndrome or Aarskog syndrome, surgical intervention may be an option. This depends on the extent of the four-finger furrow and any other malformations. The four-finger furrow itself is not a priority for treatment and follow-up. The most important follow-up measure is to monitor the further symptoms of the underlying disease and to provide the patient or the parents with further measures to better cope with the clinical picture. Follow-up care for a four-finger furrow is provided by the general practitioner. He diagnoses the four-finger furrow and can refer the patient to an appropriate specialist. In most cases, hereditary diseases can be recognized by other, more obvious symptoms. The four-finger furrow is a typical sign that must be included in the diagnosis. After the causative disease has been diagnosed, further therapeutic measures can be discussed. Due to the variety of possible conditions that can be associated with a four-finger furrow, follow-up care must always be selected on an individual basis. Follow-up care is determined by the physician in charge. Inasmuch as the four-finger furrow occurs without causative disease, no follow-up care is needed.
This is what you can do yourself
A four-finger furrow is not a physical impairment. Treatment of the external feature is not necessary unless the furrow is unusually pronounced and thus limits the mobility of the hand. Parents who notice a four-finger furrow in their child are best advised to speak with their pediatrician. Further tests can determine whether the four-finger furrow is due to a genetic change such as trisomy 21. In most cases, however, the external signs are sufficient to determine or rule out such a condition on their own. If the four-finger furrow occurs independently of a disease, no further measures need to be taken. The child can be educated later about the cause of the four-finger furrow. If the four-finger furrow occurs in the context of a disease, the disease must be treated first. Monkey furrow itself does not require treatment. It occurs in up to four percent of the European population and has no further relevance to the child’s health. Nevertheless, any abnormalities should be observed and a specialist consulted if necessary. Research is ongoing, particularly in the area of genetic disorders, and new findings linking the four-finger furrow to physical diseases cannot be ruled out.
