Broke a knee in half & 180'd the lower half of my leg in the process (literal sideways 180, heel of my foot was under my chin); probably the most painful single injury - as well as the one that's had the most negative effect on day to day life since. RIP sport... and walking correctly.

Managing to destroy a shoulder's rotator cuff was also pretty special, if you like reoccurring injuries that get worse every time you aggravate them.

TBH I rate both as worse than the multiple skull fractures from sports, or manaing to break 4 knuckles on each hand fighting.