Kyle Lohse has been dealing with forearm issues for the better part of a calendar year. Most recently he felt some pain in a start against the Angels, and when an MRI revealed inflammation, Lohse visited a specialist, who determined that Lohse is suffering from a rare condition in his right arm:
Cardinals starting pitcher Kyle Lohse is suffering from a rare condition that either requires surgery or necessitates a permanent role change, say sources familiar with the diagnosis given Lohse on Wednesday by an Anaheim, Calif., specialist.
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[The specialist] found Lohse to be suffering from exertional compartment syndrome, a condition in which the sheath covering a muscle in the pitcher's forearm fails to allow it to expand.
It's as unprecedented a baseball injury as they come - this syndrome is more commonly associated with distance runners and motocross riders. And, short of surgery, there is no cure. If Lohse opts to go under the knife, he could miss anywhere between two months and the rest of the season. His other option is to become a short reliever, but given that this is a condition that intensified with effort, the problem would likely follow him to the bullpen as well.
Lohse says he's been pitching through discomfort since spring training, which might explain why his numbers have taken a turn for the worse. He remains under contract with St. Louis through 2012, with each of the next two seasons worth $11.875m.
It's not yet known how the Cardinals will attempt to fill the void in their rotation. Read more at Viva El Bidos.