Observing litter pan habits!

Now until today I have never really took much notice of Lilly's habits and ritual when she goes to the litter pan but today I have notice she will obsessively comb as the litter and then when she poops she puts all four paws on the edge of the pan normally two front in the corner and then one back paw either side and then tenses to poop. Now I cant tell if this labored straining or not as there's no vocalization just a visible flex and tense down her arched spine. I don't know if she has always done this as the tray is normally hooded and until today her cage (shes on cage rest with a broken leg) has been in the corner down the side of my big cuddle chair which has high arms so I have never really observed her before. Does this sound like shes struggling the poops are formed and have some softness to them by the looks and do not seem dry or crumbly. Any ideas hoping I am not dealing with an obstruction as she has already had one op recently to fix the broken leg.

it sounds a little odd that she actually straddles the litter box, but the straining part doesn't sound too odd.  I watch my cats too, and they usually hunch over I see their backs kind of ripple as they push down to force the stools out.  This does not sound like any sort of blockage to me, but it sounds like she wants to make sure she doesn't get anything on her furry little feet

I phoned our vet afterwards because it seemed so hilariously odd and she said that its probably just a comfortable way for her to stand but we did buy a new litter and it sa bit more grainy then what we have used before it could be that. Hmmmm will have to keep an eye out