[Carpal malalignment following distal radius fracture].

Area of Science:

• Orthopedics
• Hand Surgery
• Radiology

Background:

• Adaptive carpal malalignment is a secondary condition arising from malunited distal radius fractures.
• It involves compensatory changes in the proximal carpal row due to radial epiphysis disorientation.
• This malalignment is often overlooked, presenting in young patients with moderate deformities and good wrist mobility.

Purpose of the Study:

• To describe the pathophysiology, clinical presentation, diagnostic methods, and treatment of adaptive carpal malalignment.
• To differentiate between midcarpal and radiocarpal adaptive mechanisms.
• To evaluate the long-term prognosis and treatment options for this condition.

Main Methods:

• Review of radiographic (strict lateral X-ray views) and clinical findings in patients with distal radius malunion.
• Analysis of the biomechanical adaptations within the carpus.
• Discussion of clinical presentation, including pain and snapping sensations.

Main Results:

• Two types of adaptive malalignment identified: midcarpal (lunate-capitate flexion) and radiocarpal (lunate flexion and dorsal displacement).
• Symptoms include dorsal wrist pain and snapping, often occurring in active young patients with preserved wrist motion.
• The condition typically leads to a stiff but ultimately painless wrist, with no increased risk of osteoarthritis.
• Osteotomy for malunion correction is the primary treatment for symptomatic cases.

Conclusions:

• Adaptive carpal malalignment is a predictable consequence of distal radius malunion, with distinct radiographic and clinical features.
• While often functionally well-tolerated long-term, surgical intervention is indicated for persistent pain and functional limitation in active individuals.
• Accurate diagnosis via specific radiographic views is crucial for appropriate management.