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A three-dimensional analysis of the sigmoid notch
Evan D Collins1, Faranak Vossoughi
1Center of Orthopaedic Surgery at Methodist Hospital, Houston, Texas, USA.
Orthopedic Reviews
|February 23, 2012
Summary
Distal radius fractures often involve the sigmoid notch, which X-rays can underestimate. This study details sigmoid notch anatomy, crucial for understanding distal radioulnar joint injuries and developing new treatments.
Area of Science:
- Orthopedic surgery
- Radiology
- Anatomy
Background:
- Distal radius fractures are common upper extremity injuries.
- Current treatments may not fully address persistent sequelae.
- X-ray imaging often underestimates sigmoid notch involvement.
Purpose of the Study:
- To quantify the anatomy of the sigmoid notch.
- To identify landmarks of the articular surface and distal radioulnar joint (DRUJ) capsule.
- To establish a classification for sigmoid notch disruption patterns.
Main Methods:
- Computed tomography (CT) scans of cadaveric hands.
- Dissection and 3D reconstruction of the distal radius and sigmoid notch.
- Measurement of sigmoid notch surface area, width, curvature, version, and depth.
Main Results:
- The sigmoid notch is flatter than previously thought.
- Only 69% of the sigmoid notch surface is covered by cartilage.
- The average retroversion is 9 degrees, with inclination nearly parallel to the radial axis.
Conclusions:
- Detailed anatomical data of the sigmoid notch are provided.
- Findings have clinical implications for evaluating DRUJ involvement in distal radius fractures and degenerative diseases.
- Results may inform future development of distal radius hemiarthroplasty.
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