Tibial torsion

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

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 ¹. External tibial torsion is a cause of out-toeing and is less common, usually occurring later at an age of 4-7 years ¹.

A severe residual deformity can result in functional and cosmetic or psychological disorders or can even cause osteoarthritis or chondromalacia patellae if serious ².

Measurement

Apart from clinical measurements, different imaging methods (2D-CT and 3D-CT) have been suggested with various reference axis used ^2-6.

• proximal reference axes:

  • 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

• distal reference axes:

  • a line through the middle of two ellipses marked by the fibular notch and the medial malleolus ^5,6

  • bimalleolar or transmalleolar axis: bisection of the tibial plafond, connecting the most protruding parts of the medial and lateral malleolus to measure tibiofibular torsion ^5,6

Interpretation

Normal values differ with the imaging method and reference axes. Intraindividual rotational side differences >15° are considered abnormal ^6,7.

See also

• torsion (bone)

• femoral anteversion