True congenital gigantism: causes, symptoms, diagnosis, treatment

True congenital gigantism (macrodactyly) is a developmental disorder caused by a violation of the linear and volumetric parameters of the upper extremity in the direction of increase.

ICD-10 code

Q74.0 True congenital gigantism (macrodactyly).

Classification and symptoms of true innate gigantism

There are three forms of this anomaly.

• The first form is a true congenital gigantism with a predominant increase in soft tissues. Distinctive features: an increase in the length and volume of all limb segments, a sharp increase in soft tissues mainly along the palmar surface of the hand (the limb has an ugly appearance); the degree of increase in soft tissues along the length and especially in width exceeds the degree of increase in the bones of the skeleton in comparison with the age norm. Observe also clinodactyly at the level of interphalangeal and metacarpophalangeal joints of the affected fingers, hyperextension in them.
• The second form is a true congenital gigantism with a predominant increase in the bone component. Characteristic features: an increase in the length of affected segments of the limb (soft tissue does not change the appearance of the affected segment); the degree of increase in the bones of the skeleton in width and especially in length exceeds the degree of increase in soft tissues in comparison with the age norm; clinodactyly at the level of interphalangeal and metacarpophalangeal joints of the affected fingers, there is no hyperextension in them.
• The third form is a true congenital gigantism with a predominant lesion of the short muscles of the wrist (muscular form). Characteristic features: an increase in the length of the affected limb segment due to metacarpal bones; increase in the volume of soft tissues of the forearm; a significant increase in the width of the palm due to the inter-cavity spacing; in comparison with the age norm, the degree of soft tissue enlargement (only at the level of the metacarpal heads) is much wider in width than the degree of increase in the bones of the skeleton (only the bone component increases in length). Detecting clinodactyly and flexural contractures in the metacarpophalangeal joints, as well as observe "looseness" in the joints of the first finger.

Treatment of true innate gigantism

Operative treatment of children with gigantism of the upper extremity of various degrees begins with a 6-7-month-old age. You can reduce the length of the enlarged finger to the norm by shortening the resection of phalanges and metacarpal bones. Elimination of the clododactyly of the affected fingers is performed simultaneously with their shortening.

Elimination of the syndactyly of the affected fingers is performed after complete normalization of their length.

If the finger is increased by 300% of the norm (or more) and the only way out is amputation, we suggest a microsurgical transplantation of the toes to the wrist (to the position of the excessively enlarged fingers of the hand).

• With the first form of gigantism, it is possible to reduce the volume of the affected segment to almost normal size with the help of a lateral resection of phalanges, which is performed in two stages: first one side of the finger, then the other.
• With the second form of gigantism, a central phalangeal resection is performed to reduce the finger in the volume.
• With the third form of gigantism, to reduce the width of the palm and simultaneously eliminate the flexion contractures in the metacarpophalangeal joints, the method of convergence of the metacarpal bones with various fixation methods is used (depending on the child's age and severity of deformation).

Simultaneously with elimination of the main manifestations of the defect, correction of accompanying deformations is performed: excision of excess soft tissues of various localization, elimination of hyperextension of the affected fingers, elimination of "looseness" in the metacarpophalangeal joint of the first finger.

The applied orthopedic-surgical methods allow to approximate the sizes of the enlarged segments to the physiological norm while maintaining the anatomical proportions of the hand.