(Portland, OR)  --  A Portland man is accused of causing multiple injuries to his three-month-old son, including a skull fracture.  Jason Anzaldi is being held in the Multnomah County Detention center after being arrested on multiple counts of first-degree criminal mistreatment.  Police say the boy was brought to a hospital on March 22nd for treatment of a serious head injury and physicians said he was also found to have suffered broken ribs, an ankle fracture and bites to his foot.  Anzaldi was arraigned yesterday and is due in court again on April 15th.