I broke the scaphod in my left wrist last week. The next day I got a long arm cast with a thumb spica. The cast has been deteriorating, as it’s an older style plaster cast rather than fiberglass and the water has been getting to it while outdoors, as well as my high level of activity. Originally I questioned the cast needing to be full, as it makes typing pretty difficult. Since the the cast has stretched so that I can type, but I feel a dull pain in my wrist when I do, and I worry that the position isn’t doing my wrist any good.

The thumb spica was in pretty bad shape so I used the serrated blade in the leatherman to cut the plaster then some scissors to remove the padding. Does Thumb Immobilization Contribute to Scaphoid Fracture Stability? (March 2008) concludes:

There was no significant difference in fracture angulation or rotation between spica and short arm casts.

I’m still waiting on deciding if I want to cut off the long arm portion of the cast or now. You can’t get the full copy of Current Concepts in the Treatment of Scaphoid Fractures (April 2004) without paying but it says:

Conservative therapy should be reserved to fracture types, which are stable and heal reliably in the lower-arm plaster cast within 6 weeks.

Opinions here still lean towards long arm casts. Studies do seem to indicate that initial time spent in a long arm cast is beneficial.