Corporal punishment needs no further explanation. Amputation to「sever prick (丰) that is falling apart, splitting」as a medical procedure needs no explanation (see 必). Whacking off at the knee was needed for a progressive case of gangrene in the feet as「falling apart with reaming.」No-longer-integrated feet were intended to have「loose and irregular movement with reaming」as the ball of the foot flapped over the top of an erection and was used to apply internal pressure, before the meat rotted and fell apart completely.
　Foot dis-integrating and binding was:
　「…[T]he custom of applying painfully tight binding to the feet of young girls to prevent further growth. …Women, their families, and [a husband] took great pride in tiny feet, with the ideal length, called the 'Golden Lotus,' being about 7 cm (2.75 inches) long. …To enable the size of the feet to be reduced, the toes on each foot were curled under, then pressed with great force downwards and squeezed into the sole of the foot until the toes broke. The broken toes were held tightly against the sole of the foot while the foot was then drawn down straight with the leg and the arch forcibly broken. The bandages were repeatedly wound in a figure-eight movement, starting at the inside of the foot at the instep, then carried over the toes, under the foot, and around the heel, the freshly broken toes being pressed tightly into the sole of the foot. …The tightness of the binding meant that the circulation in the feet was faulty, and the circulation to the toes was almost cut off, so any injuries to the toes were unlikely to heal and were likely to gradually worsen and lead to infected toes and rotting flesh. If the infection in the feet and toes entered the bones, it could cause them to soften, which could result in toes dropping off. Although, this was seen as a benefit because the feet could then be bound even more tightly. Girls whose toes were more fleshy would sometimes have shards of glass or pieces of broken tiles inserted within the binding next to her feet and between her toes to cause injury and introduce infection deliberately. Disease inevitably followed infection, meaning that death from septic shock could result from foot-binding, and a surviving girl was more at risk for medical problems as she grew older.」
　「At the beginning of the binding, many of the foot bones would remain broken, often for years. However, as the girl grew older, the bones would begin to heal. Even after the foot bones had healed, they were prone to re-breaking repeatedly, especially when the girl was in her teenage years and her feet were still soft. …Qing Dynasty sex manuals listed 48 different ways of playing with women's bound feet.」
　　[　https://en.wikipedia.org/wiki/Foot_binding 2012-12-17, emphasis ours　]　

Modern definitions (that generally disregard history) …excluding politically incorrect concepts and other meanings deemed offensive today; may list only pigeonholed definitions, euphemisms, or meaningless mnemonics)
Chinese: amputation of limbs as corporal punishment; variant of 腓, calf