Can a cortisone inj. be long term cure for torn cartilage in the wrist or will it mask it for a couple of months. as my specialist suggest ulnar short?

Temporary solution: Cortisone is a potent anti-inflammatory and controls pain very well in the short term, but is never curative. The torn ligaments in the wrist will have to be addressed at some point as they will continually be aggravated and alter your wrist biomechanics. The cortisone will give you temporary pain relief and for a variable time range, sometimes a few days up to several months.

Let me explain: Steroid injection it will not cure torn cartilage in any place, it give relief of the inflammation in the wrist area sequence to torn cartilage. If he suggests ulnar shorting it must a good reason for that.