Patients with cleft hand present with a spectrum of clinical features:
- commonly, absence of third ray structures:
- middle finger absent
- may be associated with hypoplasia or absence of the middle finger metacarpal
- less frequently, absence of neighbouring digits:
- typically, loss of three central rays leading to a two-fingered phenotype
- if they are present, these bordering digits may exhibit relative hypertrophy compared to the contralateral side
- possible syndactyly of digits either side of cleft
- with worsening of the deficit, the radial side is increasingly affected and at its extreme, a single fifth ray (little finger) may be present
- phalnageal abnormalities:
- angulation
- rotation
- delta-shaped phalanges
- longitudinally bracketed epiphyses
- flexion contractures of proximal interphalangeal joints
- metacarpal abnormalities:
- fusion
- two metacarpals may support one phalanx on one side of the cleft
- bifid metacarpals supporting one phalanx
- transverse or 'cross bones' at level of metacarpal; form a triangle attached at either end by a joint of synostosis to the border rays of the cleft
- tendon abnormalities:
- both intrinsic and extrinsic tendons present but may insert in an anomalous manner
- intrinsic muscles of thumb particularly affected
In typical cleft hand, these findings are often bilateral. With split-hand split-foot, clefting can occur in the feet.