Error in O'Sullivan Test?

[kleighhoot]

Reviewing what I got wrong and came across this in an explanation

"Subtalar joint pronation will occur as the talus plantarflexes, adducts and inverts"

I thought the components of pronation were hindfoot eversion, forefoot abduction and talocural dorsiflexion.

Am I missing something is subtalar pronation completely different than pronation? Or am I just overreacting and O'Sullivan is wrong?

 

[markelmarcel]

Yes the STJ can pronate itself- I always considered it to be PF/ADD or DF/ABD, but I can buy inversion too!
The foot as a whole also pronates.
For pronation the calcaneous must evert, talus pf & add, and tibia internal/medial rotation
(Supination would be the opposite and the above only applies when weight bearing)

 

[Jarrodmac10]

I believe O’Sullivan is correct, and I think the best way to look at this is in a CKC. As the calcaneus is fixed to the surface, the talus must adduct and PF to achieve pronation of the ST joint, the tibia will follow by IR. Hope that helps! I like the image below in the link.

http://moon.ouhsc.edu/dthompso/gait/KNMATICS/stjclos.gif

 

[markelmarcel]

Oooh, I liked that image, Jarrodmac!