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The neck-shaft angle: an update on reference values and associated factors
Cornelius S Fischer1, Jens-Peter Kühn2,3, Henry Völzke4
1Clinic of Trauma, Reconstructive Surgery and Rehabilitation Medicine, University Medicine Greifswald, Greifswald.
Acta Orthopaedica
|November 19, 2019
Summary
The neck-shaft angle (NSA) in adults is influenced by age, sex, and body measurements. Current reference values may overestimate hip pathology, as the historical lower limit of 120° appears too high.
Area of Science:
- Orthopedics
- Radiology
- Population Health
Background:
- The neck-shaft angle (NSA) is crucial for hip diagnostics and treatment.
- Existing NSA reference values often lack generalizability, stemming from limited or specialized populations.
Purpose of the Study:
- To determine factors associated with NSA in a general adult population.
- To reassess historical NSA reference values using population-based data.
Main Methods:
- MRI measurements of NSA on 3,226 participants from the population-based Study of Health in Pomerania (SHIP).
- Bivariable linear regression and quantile regression analyses to assess associations with demographic and anthropometric data.
Main Results:
- The mean NSA was 127° (SD 7), with a reference range of 114°-140°.
- Men exhibited lower NSA than women. NSA decreased with age, increased with height, and decreased with BMI and waist circumference.
- No association was found between body weight and NSA.
Conclusions:
- The historical lower NSA limit of 120° may be too high, potentially leading to overestimation of hip pathology.
- Age, sex, and body height significantly influence NSA, confirming previous findings.
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