Médecine et chirurgie du pied


Instability and laxity in rearfoot insufficiency syndrome Volume 22, issue 4, Décembre 2006


Rearfoot insufficiency is a generic concept that covers insufficiency caused by instability – the loss of active stability (reflecting a neurological disorder) – and laxity caused by the loss of passive stability (reflecting a ligament disorder).

Correct classification of instability and laxity has surgical significance. Retightening the retinaculum of the extensors is indicated in the management of instability caused by proprioceptive impairment, since it forewarns the numerous proprioceptors in the retinaculum and induces active stability, but is ineffective in the presence of laxity, making desmoplasty the more appropriate procedure.

Failure to distinguish these two scenarios sometimes makes it difficult to evaluate case studies of the two procedures reported in the literature. A diagnosis of instability, in fact, may be followed by reference to surgical procedures appropriate for laxity.