Increased external tibial torsion and osteochondritis dissecans of the knee.

In the past, osteochondritis dissecans of the knee was associated with increased tibial exotorsion, established with a clinical measuring method. Now the gold standard for determining tibial torsion is computed tomography. The aim of the current study was to establish whether the abovementioned association could be confirmed in the current patients, measured with computed tomography. Confounding aberrations of femoral torsion were ruled out. Twenty-three patients with osteochondritis dissecans in 27 knees were treated between 1991 and 1999. Symptoms and treatment results were comparable with those reported in the literature. Femoral and tibial torsion were measured with a computed tomography scan. The average femoral antetorsion was comparable with that in the literature. The average tibial exotorsion was significantly higher than the control value. Exotorsion was increased more in patients with bilateral osteochondritis, and extremely high in patients with persisting complaints. Increased tibial exotorsion could play a role in development of osteochondritis dissecans of the knee. Extreme exotorsion might be prognostic for persistent complaints.