Severe shooting pain in ankle…please help!

Hi.
18 years ago ( when I was 18) I broke my right tibia and had surgery.
3 pins and 1 screw were put in and later removed.
It was fine for the the last 17 years.
Last Thanksgiving, I suddenly began getting this SHARP shooting pain that began in the inside of my right ankle joint and shot up about 2 inches.
The pain was absolutely breath taking, but lasted only 2 seconds.
I went to the hospital and the doctor said it was probably torn ligaments and put me in a boot for 6 weeks. It bothered me because I did NOTHING to my ankle to cause the pain.
X rays showed arthritis.
Long story short, I have had this shooting pain episode thing on and off for a year.
I have to be on crutches at it’s worst and can’t bear weight on it.
MRI shows torn ligaments and tendons on the lower right side of my ankle and view of the inner ankle joint is blocked by what they called “artifacts”.
CT scan shows cysts growing where the screw had been and several bone chips in the joint.
Nuclear bone scan shows bone turnover up the leg about 3 inches above the ankle. My doctor cannot explain the shooting sharp pain.
I am going to Loyola Hospital on Friday for a second opinion.
Can you think of anything at all that this might be? Could the grinding of my bones ( no cartilage left) cause this sharp pain? I am seriously getting depressed. I am too young to be so debilitated! THanks!!