What is the medical term for side to side wrist movement?

Medical Terminology for Side to Side Wrist Movement

The medical term for side to side wrist movement is radioulnar deviation (RUD). 1

Anatomical Terminology and Movement Planes

• Radioulnar deviation refers to the movement of the wrist in the frontal plane, where the hand moves toward and away from the midline of the body 1
• Radial deviation (also called radial abduction) describes movement of the hand toward the thumb side (radial side) of the forearm 2
• Ulnar deviation (also called ulnar abduction) describes movement of the hand toward the little finger side (ulnar side) of the forearm 2
• This movement occurs around an anteroposterior axis through the capitate bone 3

Biomechanical Characteristics

• During radioulnar deviation, the greatest scaphoid and lunate movement occurs in the middle of the arc—slight ulnar deviation—which is frequently adopted during major hand actions 2
• The scaphoid and lunate motion is smallest at radial deviation 2
• The average width of the radiocarpal joint varies with position: 0.62 mm, 1.55 mm, and 2.0 mm (radial side) and 3.78 mm, 2.25 mm, and 1.16 mm (ulnar side) in radial deviation, neutral position, and ulnar deviation, respectively 4

Coupled Movements

• Radioulnar deviation is naturally coupled with flexion-extension movements of the wrist 5
• During radioulnar deviation, there is a significant amount of accompanying flexion-extension movement (about 75% of the primary range of motion) 5
• Extension typically couples with radial deviation, while flexion couples with ulnar deviation 5
• The range of motion in one direction (e.g., flexion-extension) is influenced by the position in the other direction (radioulnar deviation) 5

Clinical Significance

• Understanding radioulnar deviation is important for diagnosing wrist pathologies, particularly those involving the scapholunate and lunotriquetral ligaments 4
• MR arthrography with radial and/or ulnar deviation can improve diagnosis in cases where injury to these ligaments is suspected 4
• Maximum wrist range of motion occurs near the neutral position; deviation from neutral in one direction diminishes range of motion in the other 5
• For work station design and rehabilitation, the wrist should be placed at a neutral position to account for naturally coupled wrist motion 5

Imaging Considerations

• Radiographs are the initial imaging study for evaluating wrist pain that worsens with movement 1
• MRI is recommended as the next study when radiographs are normal or nonspecific 6
• Different wrist positions (radial vs. ulnar deviation) significantly affect the visualization of intrinsic ligaments during imaging 4
• During radioulnar deviation, carpal bones in the distal row rotate along with wrist movement while the scaphoid, lunate, and triquetrum primarily flex and extend 7