1. You don't do an MRI to diagnose a fracture. That's what X-rays are for. If Posh was sent for an MRI then it was to evaluate a sprain versus a tear, most likely of the ulnar collateral ligament.
Wrong, MRI's are routinely ordered by MD's to help diagnose subtle micro fractures that do not show up on routine Xray's. Also MRI's are used to look for Volar plate injuries especially in the thumb area which also do not show on plain films. Additionally plain films do not show STRESS FRACTURES in bones at the time of acute injuries as well as MRI's do. Plain films will show calcification of stress injuries weeks and months AFTER. Many times the team physicians bypass routine xrays because an MRI gives them so much more information than a plain set of X-rays.
MRI's are also used to assist in the diagnosis of several other bony conditions that do not show up in xrays like condral defects of the joints, bleeding in the bone from severe contusions and others.
2. Assuming Zach's report is an accurate rendition of what the school told him (and I'm sure it is), the relevant part is not the "no fracture" part, it's that they sent him for an MRI instead of an X-ray.
3. Absent a copy of the MRI report it's impossible to know what the actual diagnosis is. However a severe thumb sprain can be disabling for a long time. A tear would likely be a surgical problem, of course.
Either way unless it was a mild sprain I would not expect to see Posh on the court for some time, especially considering that it's his dominant hand. However there is no reason to believe that it will be anything other than a short-term issue regardless of whether it's a severe sprain or a tear that would need surgical attention. He'll be fine for next season, even if we don't see him again this year. Of course hopefully it's a mild sprain and he's able to get back sooner rather than later -but I'm sure Coach Anderson will take a long-term view of this.
And I hope McGriff gets the minutes - I've liked what I have seen from him in the limited time he gets, and I'd like to see him get more of an opportunity.