Sound like a tough case and may depend on how bad the break was. Hand case are difficult and it is unclear whether this would have to be filed as a 1983 action ( civil rights case ) since your boyfriend is in custody or whether it would be a malpractice case. Either way, if you think he received poor medical care, you should discuss with a local malpractice attorney who can order the records and investigate.
In addition to the info supplied by others, this would also be in the nature of a government claim case (assuming he was treated in the prison hospital) with a 6 month window to file the proper papers.
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