Hi
@Colin of Kent, I gave up on the 45 degree angle needle inserts into my abdomen early on. I am lean and rotating sites on my abdomen has been my preferred body site for 7 years +. using an Animas pump.
When I removed the 45ers as a called them, the last 1/5 or less of the plastic cannula was bent. I figured this was from hitting the underlying muscle sheath or other connective, non-fat tissue.
I graduated to 90 degree needle insets of 6 mm length because I could not obtain a short-enough 45er needle insert (Animas).
The firing mechanism of these 90 degree needle inserts makes for occasional bends occurring in the plastic cannula ( that is my excuse for it )!!! so technique is more important than with the 45ers to get the base plate of the mechanism 90 degree to the shin surface. But these are bends at least 50% or higher up the 6 mm cannula length which to me rules out the needle hitting muscle or fibrous tissue but rather the needle going in at a slant and then being bent as the sticky material grabs and the tubing is connected. The point is that sometimes these bends will be enough to cause reduced insulin delivery without setting off the obstruction alarm.
I have not ever used the Omnipod, but I gather it fires in a needle at 45 degrees to a depth of 0.65 mm.