For those who can't wait for the confirmation, the rational take would be Sanji hurts his leg trying to attack Seraphim Jinbe but the part about his body getting dislocated is probably an exaggeration. Sanji doesn't use DJ or IJ but if Sanji attacks after seeing Franky and others fail, then there is a chance he used Haki although it won't be shown as always due to the boots Sanji's wearing. It's worth noting Sanji is faster with those boots as they're said to make users feel light.