Let us focus on the key words "well-spaced." The horns must be far enough apart at the base (three fingers' width or more) that another goat leg cannot be caught/stuck between the horns. Why would that be important? Well, when boy goats rough-house, one of the favorite techniques is to lower the head to show off the horns, and then toss the head up. When one goat goes low and one goat jumps to avoid it, there is a good chance of snagging an ankle.
When I left the house to go to work this morning, I heard the goat-in-distress-for-real bellow up front in the boy's yard. Theo was down and it looked like Loki was still beating on him. I tore up front in my hose and heels to discover that Theo's back left leg was stuck in Loki's horns. Loki wasn't making it any easier for Theo to get loose because Loki kept tossing his head up to try to get loose rather than down, wedging Theo's leg in further.
But by the time I ran up to them, Theo was on his three available feet and he and Loki were trying to avoid me while still stuck together. Argh. I chased them a little ways before Loki dropped his head to avoid my grab, and Theo's leg slid up and out.
I stood there a few moments watching while Theo tested his leg. By the time I left, he was limping but putting weight on it. I wasn't in the proper attire to try to catch him without going back for bribery, and he was walking, so I left. Since Theo had some weight on his leg when he limped off, I'm going to go with the theory that it is bruised and sore but not broken.