Brachydactyly (hypophalanges, microdactyly) – short bones, congenital anomaly of the extremities, expressed in the presence of a child’s short fingers due to shortening or absence of individual phalanges. Brachydactyly is a dominantly inherited trait, i.e., for the manifestation of an abnormality in a child, the brachydactyly gene must be inherited from one of the parents.
In the absence of other anomalies, people with brachydactyly can live a normal, normal life, but short-range imposes restrictions on professional choice. Brachydactyly occurs with equal frequency among both sexes; the prevalence in the population is 1.5: 100,000.
Child Brachidactyl Classification
In traumatology and orthopedics, there are several types of brachydactyly.
- Type A brachydactyly characterizes the shortening of the middle phalanges of the fingers, the radial curvature of the phalanges, and the dysplasia of the nail plates.
- With type A1 brachydactyly (Farabi type), the rudimentary structure of the middle phalanges is noted, sometimes – their merging with terminal phalanges. There is a shortening of the proximal phalanges of the first fingers and toes, growth retardation.
- For brachydactyly type A2 (brahimesofalangii, type Mora-Brita) is characteristic of the shortening of the middle phalanges of the second fingers and toes; while the other fingers are relatively safe. The middle phalanges of the second fingers have a triangular or rhomboid shape and radial deviation.
- With brachydactyly type A3 (brahimesophalania of the fifth finger, clinodactyly), shortening and radial curvature of the middle phalanges of the fifth fingers of the hands are observed.
- Type A4 brachydactyly (brahimesophalania II and V fingers, Temtam type) is characterized by affection of the middle phalanxes of the second and fifth fingers of the hand.
- With brachydactyly type A5, there are no middle phalanges of the second to fifth fingers and there is nail dysplasia.
- Type B brachydactyly is characterized not only by a decrease in the length of the middle phalanges, but also by an underdevelopment or the complete absence of distal (terminal) phalanges and syndactyly (fusion) of the second and third fingers.
- Type C brachydactyly is distinguished by shortening the proximal and middle phalanges of the second and third fingers. This type of brachydactyly is often accompanied by symphalangy (fusion of the phalanges), shortening of the metacarpal bones. It can be combined with short stature and mental retardation.
- Type D brachydactyly (brachimegalodactyly) is diagnosed by shortening the first fingers and toes.
- Type E brachydactyly is characterized by shortening of the metacarpal and metatarsal bones (bones of the hand and foot).
The most common in clinical practice is brachydactyly types A3 and D.
Symptoms of brachydactyly in a child
Brachydactyly may be an isolated congenital abnormality, but in some cases shortness is accompanied by other congenital syndromes. Thus, in Down syndrome, along with brachydactyly, there are the following characteristic features: brachycephaly, short neck, epicanthus, cataract, dentition anomalies, sulcus, congenital heart defects, strabismus, chest deformity (funnel-shaped or keel-shaped), etc.
The minimum diagnostic signs of Baymond syndrome are brachydactyly, nystagmus, cerebellar ataxia. In Poland syndrome, there are no large and small pectoral muscles; there is brachydactyly, syndactyly, nipple aplasia or amastia, rib deformity, etc.
The syndrome of the midline facial cleft is characterized by microgenia, choanal atresia, hypoplasia of the frontal sinuses, brachydactyly, pituitary nanism, secondary hypothyroidism, bilateral cryptorchidism, curvature of the penis, oligophrenia, etc.
In Aarskog-Scott syndrome, in addition to brachydactyly, hypertelorism, short stature, laxity of the joints, syndactyly, scab-shaped scrotum, phimosis, cryptorchidism, inguinal hernia, and mental retardation occur.
Actually brachydactyly is accompanied by pathological shortening of the fingers and toes, sometimes by their flattened shape or splitting. Depending on the severity of the pathology, brachydactyly can be combined with stiffness in the joints (simfalangiya), syndactyly, polydactyly, muscular weakness, in a complex disrupting the normal functioning of the hand or foot. With brachydactyly, hypoplasia or aplasia of the nail plates is often observed.
The special cases of brachydactyly include ectrodactyly and adactyly. Under ectrodactyly, underdevelopment of the distal (nail) phalanges is observed; in severe cases – the absence of nail and middle phalanges. The development of metacarpal bones does not suffer. In case of adactylia, there is a congenital absence of phalanges of the fingers with partial or complete preservation of the metacarpal bones.
Diagnosis of brachydactyly in a child
Brachydactyly in a child can be diagnosed in the prenatal or postnatal period. Prenatal diagnosis may include genetic counseling (if there is a family history of brachydactyly) and 3D ultrasound, carried out during the gestational pregnancy period of 20-24 weeks.
Identification of isolated brachydactyly is not a reason for abortion; when chromosomal syndromes are detected, the problem is solved individually.
After birth, the diagnosis of brachydactylia is established by a children’s orthopedic traumatologist on the basis of a clinical examination and X-ray data (X-ray of fingers, bones of hand, toes, foot bones). The results of DNA diagnostics are crucial.
Treatment of brachydactyly in a child
Both conservative and surgical methods are used in the treatment of brachydactyly. In some cases, to restore the function of the hand or foot is sufficient to conduct courses of physical therapy and massage. This allows you to improve the work of the musculo-ligamentous apparatus and to avoid limitation of motor activity.
The purpose of the surgical correction of brachydactyly is the change in the linear dimensions of the hand, the elimination of concomitant symphalangy and syndactyly. In order to correct the linear dimensions of the fingers, distraction, pollicization, microsurgical autotransplantation of the toe on the hand can be performed.
Syndactyly surgery involves the separation of accrete fingers with skin, tendon-muscle or bone grafting. Surgical treatment of brachydactyly is aimed primarily at maximizing the restoration of hand function and, secondly, at achieving an acceptable aesthetic result.
Brachydactyly is a hereditary defect characterized by the underdevelopment of the phalanges and the shortening of the fingers or toes. Symptoms of brachydacty include short bones, shortening of the size of the hand or foot, hypoplasia of the nail plates, often stiff joints (symphalangia), syndactyly, polydactyly.
Examination of a patient with brachydactyly includes genetic counseling, DNA diagnostics, and x-rays of the hands and feet. Treatment of brachydactyly includes the separation and elongation of the fingers, exercise therapy and massage.
Prevention of brachydactyly
Specific prevention is not developed due to the fact that brachydactyly is a genetically determined, inherited anomaly.
Preventive work includes medical and genetic counseling for families with burdened heredity to determine the likelihood of having a child with brachydactyly; exclusion of related marriages.