The first thing i would do is treat that wound,clean it really well and apply an antibiotic ointment(nothing ending in "caine/cane" toxic to birds. The reason i suggest treating this first is you do not want this wound covered by any wrap while treating for fracture/slipped tendon. Looks almost like skin has been torn.
To check for a slipped tendon,run your thumbs down back of leg from hock(leg joins body)to shank(scales start)if tendon has slipped you will feel it,it will feel loose/springy if you press down you can feel it snap back into place,compare to other leg so you know how it should feel. Press back into place,you may have to do this several times,you can wrap leg at tendon to keep it in place. You can also try stretching exercises,gently pull leg back,like chick would while normally stretching,this stretches tendon. If chick displays pain with stretching,then stop or perhaps you may have been stretching to hard. Slipped tendon can be very painful. I have successfully treated this in a adult rooster,it did take approx 2-3 weeks before my boy was walking normal