A conversation with Minnesota Twins physician Dr. Jon Hallberg about second opinions. Hallberg uses the example of Twins rookie catcher Joe Mauer, who has had his share of health problems over the past few months.

Most recently, Mauer had a bout of kidney stones. But a left knee injury is what has caused the most consternation for the young star and his fans. During a stint in July and August, Mauer was seeking several opinions from doctors about whether or not his joint needed surgery. Mauer may be back this season, but healing has been slow.