Wrist_and_Hand__Congenital__Anomalies__and__Normal_Variants

Wrist and Hand

Overview

• Discussion on congenital anomalies and normal variants in wrist and hand imaging.

• Course: RAD6210 - Normal Imaging of the Spine & Extremities

• Instructor: Dr. F. Jarrett-Thelwell

Congenital Anomalies

Madelung’s Deformity

• Definition: Premature fusion of the medial portion of the distal radial physis.

• Results in:

  • Short bowed radius

  • Ulnar tilt of the distal articular surface of the radius

  • Volar tilt of the distal articular surface of the radius

  • Dorsal subluxation/dislocation of the ulna at the distal radioulnar joint (DRUJ)

  • Relatively long ulna compared to radius

• Causes:

  • Trauma

  • Dysplasia

  • Genetic syndromes

  • Idiopathic origin

Carpal Coalition

• Definition: Fusion of 2 or more carpal bones.

• Common Causes:

  • Acquired (due to inflammatory arthritis, infection, trauma, post-surgical changes)

  • Congenital (failure of embryonic cartilaginous segmentation and joint formation)

• Bilateral occurrence: 60% of cases

• Most common coalition: Luno-triquetral coalition

Distal Radioulnar Synostosis

• Definition: An abnormal fusion (osseo or fibrous) of the distal radius and ulna.

Polydactyly

• Definition: An increase in the number of fingers or toes.

Syndactyly

• Definition: Most common developmental anomaly of the hand.

• Types:

  • Skin fusion between digits (syndactyly)

  • Bony fusion of phalanges of adjacent digits (synostosis)

• Development Timeline: Occurs during the 5th week of fetal development.