I did find this page, which appears to have good information, but the causes are too vague for my purposes.
The husband of the character in question is supposed to have lost control (likely in a fit of rage) and caused permanent injury to his wife. Their son is retelling the events years later, and he needs to emphasize that it was very serious. The husband/ father also needs to be horrified by his own actions, as he would never hurt his wife in his right mind.
The specific location can vary to suit the accident, although it would work best in a home or other private property where the characters could have been alone during the incident. The story takes place in a fictional city. Most of the buildings aren't more than a few storeys high, but there are exceptions.
I don't need to go into in-depth explanation in my story, but I haven't found much that can tell me if she could break her legs and possibly arms in the same incident that causes a spinal injury without it being a car accident.
It is important that she survives, but it's fine for it to be touch and go for a while. A hint of implausibility is okay.
How far would she need to fall to have a spinal injury and possible broken limbs? Is it at all possible for her to suffer a spinal injury as the result of being thrown with force against a hard surface instead of being pushed (out a window or off a balcony) and falling? It's okay if the force seems implausible for an adult male to cause on his own, as the husband is meant to have abnormal strength. But if it's closer to impossible, he could have pushed his wife out of a window or off a balcony.
Any suggestions or direction to information that could help would be appreciated.