having ur pain on both resistance flexion and extension suggests a muscular component however u did not mention anything about ulna and radial deviation resistance.I think you have a classic capitate subluxation but you have not reported any abvious deformity. having pain on both passive flexion and extension and equal pain on resistance takes my mind of muscle and focuses it on joints. so I think its a capitate subluxation may be what u have is sparin of the ligaments surrounding the capitate bone. You may require some manipulation to reset it, and possibly frictions around it, but the history resembles the diagnosis justy mentioned.