Bus armrests, the ones that can be moved up or down.
Otherwise known as bus spears for creating horrendous muscle contusions and huge haematomas in your thighs and hip as the bus jerks around as you're trying to get close enough to the door to have a chance of getting off when the driver slams the brakes on at the stop.
It took eight months for the one on my left quad to finally stop hurting.
Crutches. So you've buggered up your ankle, and need to be non weightbearing for the next six weeks, eh? Well, how about also buggering up your shoulders, upper back, rotator cuff, pectorals AND the palms of your hands for the next three months? Give it 48 hours (with the use of bubble wrap, old socks and a pair of padded cycling gloves) and I can promise you that the ankle won't bother you in the fucking slightest.
Shoes. Especially 'formal' ones, the type that are expected for 'professional dress standards'. Take a wonder of evolution, a springy, shock absorbing, speed enhancing and sensitive structure like the human foot, specifically selected for to make it possible to travel great distances, climb, balance, run, creep, push, jump and generally survive in a world where a third of it is designed to see you as food, a third is designed for you to make into food whether it likes it or not and a third doesn't give a shit either way because it's inanimate but will kill you - and then encase it in rigid leather or plastic that is too tight to allow it to function, will cause blisters, sore and cuts if it's too big, too small, not quite flexible enough, too flexible or just there, disables the windlass function of the plantar fascia/arch/foot complex, puts pressure on the joints so that they become deformed after years of sideways compression, alters your gait so that excessive strain is translated from toe-foot-ankle-shin-knee-thigh-hip-pelvis-spine-neck, creates muscle imbalances and never, never fits you properly. And that's before you get to the addition of an excessively elevated portion at the back that further fucks up your body and endangers the ankles if a surface is too smooth, too uneven, too sloped, too grippy, too slippery or just fucking there on the basis that it 'looks good' and 'shows toe cleavage'. And once you've been stuck with those bastarding things for the majority of your life, even the ones designed to not actually fuck up your body are unsuitable because your body has been altered so much by the cunting things, you can't wear those without pain, either.