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Published on: January 11, 2019
Radiographic morphology of the ulnar head
E Hyams1, N Yazaki, R Nakamura
1Department of Hand Surgery, Nagoya University, Nagoya 466-8550, Japan.
Summary
Ulnar variance significantly impacts ulnar head shape, including its diameter and inclination. These findings highlight the link between ulnar variance and wrist morphology in normal individuals.
Area of Science:
- Orthopedics and Radiology
- Human Anatomy and Biomechanics
Background:
- Ulnar variance, the difference in length between the distal ulna and radius, is a critical factor in wrist biomechanics.
- Morphological variations of the ulnar head may influence wrist joint function and pathology.
- Understanding the relationship between ulnar variance and ulnar head morphology is essential for diagnosing and managing wrist conditions.
Purpose of the Study:
- To investigate the morphological characteristics of the ulnar head in relation to ulnar variance.
- To determine correlations between ulnar variance and specific measurements of the ulnar head and distal radioulnar joint.
Main Methods:
- Analysis of posteroanterior radiographs from 102 normal wrists.
- Measurement of ulnar variance, ulnar styloid length, ulnar head diameter, ulnar seat inclination, and ulnar head peak distance.
- Third metacarpal length was used as a reference for overall wrist size.
Main Results:
- Moderate correlations were found between ulnar variance and ulnar seat inclination.
- A significant correlation was observed between ulnar variance and ulnar head diameter.
- Ulnar variance also correlated with the distance of the ulnar head peak to the distal radioulnar joint.
Conclusions:
- Ulnar variance influences various aspects of ulnar head configuration, including its diameter and inclination.
- Despite considerable variations, ulnar head morphology is demonstrably affected by ulnar variance.
- These findings contribute to a better understanding of normal wrist anatomy and biomechanics.
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