Advanced Practice Providers

Meet our Team of Advanced Practice Providers


Eric Busch, PA-C

Eric Busch has been a Physician Assistant at BNA since 2002. He graduated from Cornell University Medical College Physician Assistant program. He made his decision to pursue a medical career after working as an outdoor educator at the Grand Teton National Park in Wyoming.


Michael Kiley, PA-C

Michael was originally attracted to medicine after taking a course at the University of Colorado at Boulder to become an Emergency Medical Technician (EMT). He has worked on ski patrol and as an EMT at Boulder Community Hospital before graduating from Albany Medical College’s Physician Assistant Program. He has experience in Emergency Medicine, Orthopedic Surgery and Neurosurgery.

Jennifer Tierney, MSN, FNP-BC

Jennifer joined Boulder Neurosurgical and Spine Associated in 2010 as a Registered Nurse.  She has more than 12 years of neurosurgical experience.  She graduated with her Master of Science in Nursing and Nurse Practitioner from the University of Colorado in 2016.



Trenton Stickney, PA-C

Trent graduated in 2019 from Red Rocks Community College Physician Assistant program. Prior to becoming a PA, he worked at a family practice clinic in his hometown of Conifer, CO. Trent is a Colorado native who enjoys all that Colorado has to offer.


Grant Bracken, PA-C

In 2018, Grant graduated from Augustana College in Rock Island, IL with a Bachelor’s in Neuroscience and Pre-Medicine while simultaneously working as an emergency room technician. He then completed his Master’s of Medical Science degree at Midwestern University in Downers Grove, IL in September 2020. Prior to graduating, Grant gained experience in neurosurgery while training at St. Anthony Hospital in Lakewood, CO. In his free time, he enjoy playing sports and anything that involves the outdoors.


Elizabeth Tamaren, PA-C

Liz graduated in 2021 from Red Rocks Community College Physician Assistant program. Prior to becoming a PA, she worked at a neurosurgical practice in Boulder, CO. Liz moved to Colorado from St. Louis, MO in 2016 and never plans on leaving.


Tara Adams, PA-C

Tara graduated from the Thomas Jefferson University Physician Assistant program in Philadelphia, PA, in 2021. Prior to PA school, she worked at Magee Rehabilitation Hospital for 5 years, a specialty hospital catering to spinal cord and brain injury patients. She has two labradoodles and in her free time, she enjoys snowboarding, hiking, visiting local breweries and spending time with friends and family.