Tibial torsion

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Tibial torsion refers to as the rotation or twist along the longitudinal axis of the lower leg or more specifically the tibial bone.

Usage

Internal tibial torsion is a cause of in-toeing gait a common rotational variant in toddlers, usually resolving spontaneously by the age of 5 years.  A severe residual deformity can result in functional and cosmetic or psychological disorders or can even cause osteoarthritis or chondromalacia patellae if serious .

Measurement

Apart from clinical measurements different imaging methods (2D-CT and 3D-CT) have been suggested with various reference axis used .

proximal reference axes are the following:

  • transtibial axis: defined by bisection of the proximal tibial plateau passing through the center
  • posterior condylar axis: tangent to the posterior tibial plateau above the proximal tibiofibular joint

the following distal reference axes are used:

  • a line through the middle of two ellipses marked by the fibular notch and the medial malleolus
  • bimalleolar or transmalleolar axis: bisection of the tibial plafond, connecting the most protruding parts of the medial and lateral malleolus to measure tibiofibular torsion

Interpretation

Normal values differ in regard to the imaging method and reference axes. Intraindividual rotational side differences >15° are considered abnormal .

See also