Why Analog Input to grounds reads 89ADC

Forum 2005-2010 (read only) Hardware Troubleshooting
1

When I conect it to 5V: 1023ADC. Ok. To ground 89 ¿?
I think I burned pin 50 because now gives 2,8V with no change between digitalWrite HIGH or LOW.
¿Have I burned other parts of my arduino Mega apart of the pin 50?