[Supination external rotation lesions of the ankle joint in osteoporotic lower leg specimens. Experimental induction and review of the literature].

BACKGROUND

Knowledge of the pathomechanism and the detailed extent of ankle joint lesions determines adequate therapy and success of treatment.

MATERIAL AND

METHODS

Supination external rotation lesions were induced in 29 human cadavera with a testing apparatus; 27 of these specimens were from elderly women. Bone mineral density was measured. The literature review includes experimental studies of this fracture entity.

RESULTS

We induced stage II in 42%; applying an additional lateral force on the fibula raised the incidence. The syndesmosis stayed intact in 50% although the fibula fractured at the level of the tibial plafond. Stage IV lesions were registered in 25%. The overall low bone mineral density showed a positive correlation to the angle at which the fibula fracture occurred.

CONCLUSIONS

We reproduced supination external rotation lesions according to Lauge-Hansen in osteoporotic ankles. There is a certain discrepancy between the obligatory lesion of the inferior anterior tibiofibular syndesmosis at stage II according to Lauge-Hansen, as we observed an intact syndesmosis in 50% at stage II. Stage IV defining medial malleolar fractures were reproduced after Lauge-Hansen and Michelson et al.