Physical Therapy Team


Jennifer L Johnson, PT, MPT

Director of Physical Therapy

Jennifer L Johnson, PT, MPT

Jennifer brings over 20 years experience in orthopedic manual physical therapy to OSI. She has attended numerous continuing education courses to further broaden her manual therapy skill set and utilize evidence based practice to improve patient quality of life. Jennifer has extensive experience treating patients with a wide variety of diagnoses, including post operative conditions, complex spinal disorders, and conservative management of orthopedic conditions. Jennifer is a graduate of Chapman University, receiving her Master of Physical Therapy in 2001. She graduated with High Honors from Whittier College, earning a Bachelor of Arts in Physical Education and Recreation- Pre Physical Therapy Emphasis. She values spending time with her family and enjoys watersports, boating, and tennis.

Jennifer and the entire physical therapy staff strive to work closely with each physician at OSI to provide the most comprehensive, quality healthcare to our patients.

Kristine Boyle-Walker, MPT, OCS, ATC, CHT

Assistant Director of Physical Therapy

Kristine L Boyle-Walker, MPT, OCS, CHT, ATC

Kristine graduated from Chapman University receiving her Master of Physical Therapy degree in 1994; and graduated from Cal State Long Beach with a bachelor’s degree in Physical Education - concentration in Athletic Training in 1990. She is a Board Certified Orthopedic Clinical Specialist, a Certified Hand Therapist, and a Certified Athletic Trainer. Her broad experience on the athletic field, as well as, in the clinic allows her to draw on a variety of treatment options in treating orthopedic patients. Serving as a professor at Cal State Fullerton and a frequent lecturer allows her to keep abreast of current assessment and treatment techniques. She values spending her free time with her family and enjoys watersports, skiing, mountain biking and hiking.

Katrina Parsons, MPT, OCS

Katrina Parsons PT, MPT

Katrina graduated from Cal State Long Beach with a Master’s degree in Physical Therapy in 2009 and went on to earn her Orthopaedic Clinical Specialist certification. She has worked in a variety of outpatient facilities from sports clinics to women’s health. Since 2014 she has applied her experiences as a multiple-sport athlete to the patients at Orthopaedic Specialty Institute. She specializes in movement dysfunction and concussion management and loves any challenge a patient brings. Aside from work she lives for playing outdoors, traveling and spending time with friends. She is currently active in Crossfit, mountain biking, SUP and hiking.

Louis Taylor III, MPT

Louis Taylor

Louis grew up in Placentia, CA. He graduated from Cal State Long Beach with a bachelor’s degree in kinesiology. He returned to Cal State Long Beach to receive his Master’s degree in Physical Therapy. He continues to improve his clinical skills with courses in orthopedic and sports therapy for the treatment of shoulder, knee, foot/ankle, and spine impairments. He practices manual techniques, therapeutic exercises, gait/balance training, and orthotic casting to help patients achieve their goals. He enjoys spending free time with family, traveling, snowboarding, going to concerts, and camping. He is active in weight training, cycling, and running an occasional 5K.

Marie Theilen PT, DPT

Marie Theilen

Marie graduated from Loma Linda University with her Doctorate of Physical Therapy in 2018. Prior to this, she received her Bachelor of Science in Kinesiology with a focus in Clinical Exercise Science from Cal State Fullerton. At LLU, she volunteered as a student therapist for an equine therapy program catering to the pediatric population, & thoroughly enjoyed her time as a Teacher’s Assistant in the Gross Anatomy Lab. Following graduation with her Doctorate, Marie worked as a travel PT for 2 years, with jobs anywhere from 75 to 1,700 miles from home. She made her way back to her hometown here in Orange County in 2021, & in her spare time enjoys rooting for the Angels, Ducks, & Rams, as well as being outdoors as much as she can. She has experience as a DPT in settings including but not limited to: Home Health, Skilled Nursing, Acute Rehab, Geriatrics, Pediatrics, Neurology, Cardiothoracic & of course, her passion – Orthopedics & Sports Medicine.