Determining factors in angular deformity of the knee: influence of age, gender and BMI. A preoperative study
Factores determinantes de la deformidad angular de la rodilla: influencia de la edad, el sexo y el IMC. Un studio preoperatorio
Daniel Hernandez-Vaquero, Alfonso Noriega-Fernandez, Susana Iglesias-Fernandez
Abstract
Introduction: Knowing and properly assessing the anthropometric characteristics of patients and the type and severity of femorotibial deformity can allow for planning and executing a better surgical technique in total knee replacement.
Material and methods: A descriptive and correlational study of 130 patients was conducted. The angular alignment of the leg axis was analysed using a long-leg radiograph that included the hip, knee, and ankle. 11.5% of cases were classified as having a neutral axis, 26.1% as valgus, and 62.3% as varus. The absolute value of the deformity was used for severity analysis.
Results: A positive correlation was observed between age and the severity of the deformity (r = 0.28, p = 0.001). The varus pattern was predominant in men (77.8%) and showed the strongest association with age (r = 0.42, p < 0.001), while valgus was more frequent in women. Patients with varus had a significantly higher BMI than those with valgus (p < 0.001). When severe deformities, greater than 20°, were present, a significantly higher BMI was also observed compared to the other cases (p < 0.05).
Conclusions: Older age and higher BMI are critical predictors of the severity of angular deformity, especially in the varus pattern. There is a marked sexual dimorphism, with men showing a linear progression toward varus and women accounting for most severe valgus cases. These findings underscore the importance of weight management and close follow-up in elderly patients to prevent severe joint collapse and technical difficulties in total knee replacement.
Keywords
Resumen
Introducción: Conocer y evaluar adecuadamente las características antropométricas de los pacientes, así como el tipo y la gravedad de la deformidad femorotibial, permite planificar y ejecutar una mejor técnica quirúrgica en la artroplastia total de rodilla.
Material y métodos: Se realizó un estudio descriptivo y correlacional con 130 pacientes. Se analizó la alineación angular del eje de la extremidad inferior mediante una radiografía de miembro completo que incluía cadera, rodilla y tobillo. El 11,5 % de los casos presentó un eje neutro; el 26,1 %, valgo; y el 62,3 %, varo. Para analizar la gravedad, se utilizó el valor absoluto de la deformidad.
Resultados: Se observó una correlación positiva entre la edad y la gravedad de la deformidad (r = 0,28; p = 0,001). El patrón en varo predominó en los hombres (77,8 %) y mostró la asociación más fuerte con la edad (r = 0,42; p < 0,001), mientras que el valgo fue más frecuente en las mujeres. Los pacientes con varo presentaron un IMC significativamente mayor que aquellos con valgo (p < 0,001). Asimismo, en los casos de deformidades graves (superiores a 20°), se observó un IMC significativamente más elevado en comparación con el resto de los casos (p < 0,05).
Conclusiones: La edad avanzada y un IMC elevado son factores predictores clave de la gravedad de la deformidad angular, especialmente en el patrón en varo. Existe un marcado dimorfismo sexual: los hombres muestran una progresión lineal hacia el varo, mientras que las mujeres representan la mayoría de los casos graves de valgo. Estos hallazgos subrayan la importancia del control del peso y de un seguimiento estrecho en pacientes de edad avanzada para prevenir el colapso articular grave y las dificultades técnicas durante la artroplastia total de rodilla.
Palabras clave
References
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Submitted date:
05/13/2026
Reviewed date:
08/20/2026
Accepted date:
09/13/2026
Publication date:
09/13/2026
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