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Characterization of the Sense of Agency over the Actions of Neural-machine Interface-operated Prostheses
Published on: January 7, 2019
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Positioning of the acetabular component in cemented prostheses - radiographic calculation
Pedro José Labronici1, Ramon Louro Motta2, Bruno Bandeira Esteves2
1PhD in Medicine from the Universidade Federal de São Paulo - Escola Paulista de Medicina. Head of the "Prof. Dr. Donato D'Ângelo" Orthopedics and Traumatology Service, Hospital Santa Teresa, Petrópolis, Rio de Janeiro, Brazil.
Revista Brasileira De Ortopedia
|July 16, 2019
Summary
This study confirms that plain radiographs and trigonometric formulas reliably measure acetabular cup inclination and anteversion in hip osteoarthritis, hip neck fractures, and aseptic necrosis.
Area of Science:
- Orthopedic surgery
- Radiology
- Biomechanical analysis
Background:
- Accurate measurement of acetabular cup positioning is crucial for total hip arthroplasty outcomes.
- Assessing inclination angle and anteversion using standard radiographs can be challenging.
Purpose of the Study:
- To evaluate the reliability of using plain radiographs and a trigonometric formula to measure acetabular cup inclination and anteversion.
- To compare the reliability of these measurements across different hip pathologies: osteoarthritis, aseptic necrosis, and hip neck fracture.
Main Methods:
- A retrospective analysis of 72 total hip arthroplasties in 66 patients.
- Acetabular cup inclination measured via plain radiography.
- Acetabular cup anteversion measured using a trigonometric formula.
Main Results:
- High intra- and inter-observer agreement for both inclination and anteversion measurements.
- Excellent reliability (Intraclass Correlation Coefficient > 0.80) across all measurements.
- No significant variations in measurement reliability were observed between osteoarthritis, hip neck fracture, and aseptic necrosis groups.
Conclusions:
- Plain radiographs combined with a trigonometric formula provide an accurate and reliable method for assessing acetabular cup inclination and anteversion.
- This technique is simple to implement and highly dependable for clinical use.
- The method's reliability is consistent across various hip pathologies necessitating total hip arthroplasty.
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