[Riot]

Doc, the physical ability to pin, plate, cancellous bone graft, etc. is relatively easy in a horse leg, but horses do have multiple non-human issues that appear as soon as you try to recover them from anesthesia and continues for months, predisposing them to unsuccessful outcomes.

The first is their special (non-human) weight-bearing issues - they never go non-weight-bearing (thus pin loosening and slow- or non-union is a big threat.) They will spin, turn, suddenly load, twist, strain, stomp & kick, etc, often blowing apart or damaging their repair or breaking their hardware in the immediate weeks post-surgery (huge worry).

They cannot be healthily immobile (they are physiologically designed to walk with their heads down nearly constantly). They readily have circulatory issues humans don't have regarding laminitis threat. They colic at the drop of a hat post-surgery (post-surgical ileus, hospitalization ileus). They don't mentally tolerate pain, nor do well with many common types of pain meds (opiods).

Keep them in stall rest and they urinate and defecate all over their surgical site (infection risk very high).

Multiple pin placement in a shattered pastern (and the healing involved) often permanently scars/disrupts/thickens tendons and the joint components above/below the long pastern bone (which is equivalent to P1 of your middle finger); and if you take their pins out the bone remodeling in the pin tracts is often slow and they'll lightly stomp a foot at a fly a month later and refracture right through the pin sites.

I've got a front leg skeleton from a 16.2 hh TB gelding (big horse) and the long pastern bone is 4-inches long, and at it's center I can encircle it with my thumb and forefinger with a half-inch to spare.

Tiny bones, big heavy critter that will not stand still nor non-weight bear.