He is affiliated with ProHealth Waukesha Memorial Hospital and ProHealth Oconomowoc Memorial Hospital. After completing medical school at the University of Wisconsin School of Medicine and Public Health, Dr. Nienhuis performed his residency at Mayo Clinic. On average, patients gave him a rating of 5.0 stars out of 5. He is an in-network provider for Humana HMO, Humana Bronze, and Humana Catastrophic, as well as other insurance carriers.