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Elevación de la resección distal medial reduce la densidad ósea en la artroplastia total de rodilla en valgo
Yugo Morita1, Shinichi Kuriyama1, Yuki Shinya1
1Department of Orthopaedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Resumen
Las fracturas por insuficiencia después del reemplazo de rodilla son raras pero graves. La alineación de rodilla en valgo puede provocar una menor densidad ósea en el fémur medial, lo que aumenta el riesgo de fractura durante la cirugía. La profundidad de resección cuidadosa es clave.
Área de la Ciencia:
- Cirugía Ortopédica
- Ingeniería Biomédica
- Radiología
Sus antecedentes:
- Las fracturas periprotésicas por insuficiencia después de la artroplastia total de rodilla (TKR) son complicaciones poco comunes pero graves.
- La alineación en valgo en las TKR puede provocar una descarga crónica del cóndilo femoral medial, lo que podría reducir la densidad mineral ósea (DMO) local y aumentar el riesgo de fractura.
Objetivo del estudio:
- Comparar la densidad mineral ósea (DMO) en el fémur distal entre rodillas en valgo y en varo sometidas a artroplastia total de rodilla primaria.
- Investigar el efecto de la profundidad de la resección femoral distal en la calidad ósea local en rodillas en valgo.
Principales métodos:
- Estudio retrospectivo de 40 rodillas en valgo y 40 rodillas en varo emparejadas por puntuación de propensión sometidas a TKR primaria.
- Se utilizó tomografía computarizada cuantitativa (QCT) para medir la DMO en el plano de resección femoral distal.
- Se realizaron simulaciones de resección femoral distal a diferentes profundidades (nivel del surco, 2 mm más profundo, 4 mm más profundo) en rodillas en valgo.
Principales resultados:
- Las rodillas en valgo mostraron una menor DMO en el cóndilo femoral medial, particularmente en la parte medial, en comparación con las rodillas en varo.
- Una mayor alineación en valgo se correlacionó con una menor DMO central.
- Niveles de resección de femorales distales más profundos en rodillas en valgo resultaron en una DMO progresivamente menor.
- La profundidad de la resección medial se asoció con una menor DMO en todas las regiones medidas.
Conclusiones:
- El fémur distal medial en rodillas en valgo es relativamente osteopénico.
- Las resecciones femorales distales más profundas en rodillas en valgo involucran preferentemente hueso de menor densidad, lo que aumenta el riesgo de fractura.
- El control cuidadoso de la profundidad de la resección femoral distal medial durante la corrección del valgo es crucial para mitigar el riesgo de fracturas por insuficiencia tempranas.
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