Congenital malformations of the hand The etiology of congenital malformations can be summarized into two types: one is endogenous, i.e., genetic factors. The other is exogenous, i.e. malformations occurring during the embryonic period under the influence of external factors. Classification of congenital malformations of limbs: (i) Limb formation disorders: complete or partial defects of limbs, divided into two types, transverse and longitudinal Lateral defects: 1. congenital absence of shoulder 2. congenital absence of arm 3. congenital absence of elbow 4. congenital absence of forearm 5. congenital absence of wrist 6. congenital absence of carpal bone 7. congenital absence of palm 8. congenital absence of fingers Longitudinal defects: 1. radial longitudinal defects: (1) radial dysplasia (2) (2) partial absence of the radius (3) total absence of the radius 2.ulnar longitudinal defect: (1) partial absence of the ulna (2) total absence of the ulna (3) ulnar defect combined with bony union of the humerus and radius 3.central longitudinal defect (split hand) (1) typical (2) atypical (including syndactyly and polydactyly) 4.central longitudinal arrest (seal hand) (1) complete seal hand: the upper arm and forearm are not developed, the hand is directly (2) Proximal seal hand: the upper arm is not developed, the forearm is directly attached to the shoulder (3) Distal seal hand: the forearm is absent, the hand is directly attached to the end of the upper arm (ii) Limb differentiation disorders: various factors affect the differentiation of normal limb buds into separate skeletal, skin, fascial or neurovascular tissue components Soft tissue differentiation disorders: 1. congenital multiple joint contracture 2. shoulder: incomplete shoulder descent, pectoralis muscle 3, elbow and forearm: (1) slipped extensor tendon (2) slipped flexor tendon (3) slipped intrinsic tendon 4, wrist and hand (1) cutaneous syndactyly (2) contracture secondary to muscle, ligament, joint differentiation disorders: 1st finger web contracture, joint flexion deformity, finger flexion deformity, trigger finger Skeletal differentiation disorders: 1, congenital humeral entropion 2, bony fusion of elbow joint: (1) bony fusion of humeral radius (2 (3) Total elbow osseous fusion 3. Forearm: (1) Proximal radial and ulnar osseous fusion (2) Distal radial and ulnar osseous fusion 4. Wrist and hand: (1) Osseous syndactyly: radial, central, ulnar, boxer (complete) (2) Intercarpal osseous fusion: lunar-triangular osseous fusion, cephalic-hook osseous fusion, navicular-lunar osseous fusion (3) Metacarpal Interosseous fusion (4) Interphalangeal fusion Congenital soft tissue masses 1. Angiomatous masses: (1) Capillary hemangioma (2) Spongiform hemangioma (3) Arteriovenous fistula 2. (2) central polydactyly (3) ulnar polydactyly 2, twin hand deformity also known as mirror hand 3, twin ulnar deformity (iv) overgrowth: overgrowth of the whole limb or a single part 1, all limbs 2, some limbs 3, giant fingers (v) undergrowth: incomplete limb formation, short, but complete morphology 1, all limbs 2, all hands 3, metacarpals 4, fingers (1) short finger and finger deformity (2) short finger deformity (vi) Congenital girdle syndrome: there are strips of transverse indentations on the limb, as if the indentation of a tie, and the indentation may even cause congenital amputation if it is too deep. (1) Girdle (1) Non-combined lymphedema (2) Combined lymphedema 2) Limb syndactyly 3) Intrauterine transection 4) Combined type (vii) Extensive bone anomalies Principles of treatment for congenital malformations (i) Treatment purpose: Treatment is mainly to improve function, followed by improvement of appearance (ii) Treatment timing: Malformations that hinder development will gradually worsen as the limb develops, and such malformations need early treatment. For deformities that do not prevent development, treatment can be postponed until preschool age; for surgeries involving bone orthopedics, especially those affecting bone development, it is best to extend them until after the basic bone development has stopped. (C) Multiple surgeries: Serious deformities often involve various important tissues in the hands. Surgical treatment often needs to be staged in a planned manner with developmental growth until the end of adulthood. (iv) Adjunctive treatment: congenital deformities of the hand have a great capacity for functional compensation as they develop and grow during childhood. Therefore, for certain hands with severe deformities, a positive attitude should be adopted, and conscious guidance and training from early childhood will yield good results.