About 10 months ago, I wrecked on my road bike and separated my shoulder and at the time, was told I had sprained my wrist by the ER doctor looking at my X-rays. My shoulder healed and was rehabbed over the next 2 months, however my wrist became painful to extend backwards and forwards, as well as putting any kind of weight on it. I was told again it was a sprain by the orthopedic doctor that was treating my shoulder, so I decided to go to another doctor and get a second opinion. After a new round of X-rays and an MRI, he determined that my scaphoid had indeed broken when I wrecked my bike, I just was going to have to be treated for it 3 months after the fact. Beginning a round of 6 weeks in a long arm/thumb cast, that was followed by another 3 weeks in a short arm/wrist cast, I then spent about 4 weeks in therapy as well as wearing a splint.
Currently, I've been out of therapy for about 2 and a half weeks, and my wrist still feels... Okay at best. My range of motion is largely back, I've regained most of my strength lost from the casting thanks to the PT, but my wrist still hurts at extreme extension backwards, and I experience pain across the top of my wrist whenever I put weight on it, i.e. performing a push up. My last appointment with my doctor was about 2 weeks ago as well, but he said barring a new MRI, he couldn't really be sure. I had been planning on joining the military until this almost year long fiasco has occurred, and I would like an opinion on what this pain could be from when I bend my wrist back or put weight on it, before I go drop another $600 on a second MRI.
Unfortunately, wrist injuries, and scaphoid injuries in particular, are very difficult to get over. It is not uncommon for patients to have a permanent decrease in wrist motion. The wrist does not take injury well, and tends to form quite a bit of scar tissue. The scar tissue prevents the patient from regaining full range of motion, especially hyperextension under weight.
The scaphoid is notorious for not healing well. While the vast majority do heal, there is a portion that go on to a nonunion. However, these are usually the ones that are displaced fractures. The "occult" and nondisplaced fractures almost always heal.
The problem is that the blood supply to the proximal pole is tenuous at best. The artery to the scaphoid comes in the distal pole and travels back into the proximal pole. Thus, when the scaphoid is fractured, this blood vessel can be disrupted. If this occurs, then the proximal pole can undergo AVN (avascular necrosis) and die.
But, again, this usually occurs in displaced scaphoid fractures, and what you had would be considered an "occult" scaphoid fracture. This are commonly not picked up on the first x-ray (and often not even on the 2 week repeat) and can sometimes only be seen on an MRI. But, the good thing, is that they usually heal okay.
But, that is just the bone. Remember, not just the bone is injured, but the soft tissues around the wrist are also injured, and it is the soft tissues that usually cause the problems with pain and decreased range of motion.
As to another MRI, you have to ask yourself what you are going to do with the information. If you are going to have a surgical procedure if it is not healed, then it is probably worth it. But, if you are just going to wait and see how things go, then it may not be.
Discuss it with your hand surgeon. But, you have found the common problem with wrist injures.
Great. Keep working on motion, if it does not cause too much discomfort. It is not uncommon for patients to continue to gain motion for up to a year after coming out of a cast. So, you could still regain motion.