Our Physicians
John F. Keller, M.D.
Neurosurgeon
Areas: General, Robotic Spine, Complex Spine, Artificial Disc Replacement, Cervical Arthroplasty, Spine Tumors and Coflex® Interlaminar Stabilization, Motion Preservation, Minimally Invasive Surgery (MIS)
Bryan E. Figueroa, M.D.
Neurosurgeon
Areas: Brain and Skull-Base, Cerebrovascular, Brain Aneurysm and Vascular Malformations, Carotid Artery Disease, Brain Tumors, Skull-Base Tumors, Endoscopic and Transcranial Surgeries
Justin C. Clark, M.D.
Neurosurgeon
Areas: General, Brain and Skull-Base, Vascular Lesions of the Brain and Spine, Carotid Artery Disease, Minimally Invasive Spine (MIS), Complex Spine, Thoracic Spine, Brain and Spine Tumors
Todd D. Vogel, M.D.
Neurosurgeon
Areas: General, Minimally Invasive Spine (MIS), Cervical Arthroplasty, Deformity Spinal Intervention, Osteoporosis, Spinal Oncology, Traumatic Spinal Cord Injuries and Complex Spine
Kim A. Williams Jr., M.D.
Neurosurgeon
Areas: General, Complex Spine Surgery, Minimally Invasive Surgery, Spinal Deformity Surgery, Spinal Cord Injury, Spinal Tumors
David W. Lowry, M.D.
Neurosurgeon
Areas: Minimally Invasive Spine Surgery, Robotic Spine Surgery, Disc Replacement & Motion Preservation, General Neurosurgery, Microvascular Decompression
Our Mid-level Providers
Marcia Fitzgerald, PA-C
Marcia has been working for Dr John Keller since 2001. She had 3 years of experience in Orthopedic Surgery prior to joining GLNA. She graduated with her Bachelor’s in Health Science as well as her Master’s in Physician Assistant Studies from Grand Valley State University in Grand Rapids, MI.
Brent Benso, PA-C
Brent has been working for Dr Bryan Figueroa since 2015. He had 3 years of experience in Pain Management and Neurosurgery prior to joining GLNA. He graduated with his Bachelor’s in Biology from the University of Detroit Mercy and his Master’s in Physician Assistant Studies from Mercy College in Bronx, NY.
Bradley Wernette, PA-C
Bradley has been working for Dr Todd Vogel since 2017. He had 5 years of experience in Trauma Surgery prior to joining GLNA. He graduated with his Bachelor’s in Health Professions from Grand Valley State University and his Master’s in Physician Assistant Studies from Lincoln Memorial University in Harrogate, TN. .
Noah King, PA-C
Noah has been working for Dr Kim Williams Jr. since 2024. He graduated with his Bachelor’s in Clinical Exercise Science and Community Health as well as his Master’s in Physician Assistant Studies from Central Michigan University in Mount Pleasant, Michigan.
Colton Tyson, PA-C
Colton has been working with Dr. Justin Clark since 2025. He had experience in Emergency Medicine prior to joining GLNA. He graduated with his Bachelor’s in Integrative Physiology and Health Sciences and Psychology from Alma College and his Master’s in Physician Assistant Studies from Grand Valley State University of Traverse City.
Scott M. Tuinstra, PA-C
Scott has been employed by Dr. David Lowry since 2002. He graduated from Hope College with a chemistry degree and obtained his master’s degree in Physician Assistant Studies from Arcadia University in Glenside, PA. Additionally, he holds an MBA from Grand Valley State University.