About Us

At Keystone Health & Wellness Center, our expert team of medical, chiropractic and rehabilitative staff provide superior healthcare to help you manage pain and restore well-being. 

If you live in Greenwood Village, Colorado, or the surrounding communities, seek their expert care to do more than treat your symptoms. They work with you to locate the core cause and source of your pain to address, treat, and eradicate the root of your health problems.

Our Healthcare Providers & Treatment Staff

Summer Denny, FNP-BC, Lead Nurse Practitioner

Summer Denny received her Bachelor’s of Science degree in nursing from Indiana University in Indianapolis, IN in 2011 and has spent the last seven years practicing nursing throughout the country as a travel nurse. She then received her Master’s degree as an advanced practice nurse in Family Medicine from Ohio State University in Columbus, OH in 2019.

Summer was drawn to Keystone Health and Wellness Center after seeing firsthand just how important it is to treat the body as a whole and not just the issue at hand. Summer is committed to the overall well-being of her patient’s and takes pride in treating her patients through a holistic approach. She is dedicated to finding the underlying problem and ordering therapy tailored specifically to each patient in order to improve overall health and wellness. Her primary goal is to give her patient’s a better quality of life.

Summer enjoys spending time with family and friends. She enjoys traveling, hiking, yoga, reading and painting when she’s not caring for patients.

Dr. Steven Till, DC, Clinic Director

He has been practicing as a doctor of chiropractic for 30 years and moreover, a chiropractic patient for 44 years. As with many of his colleagues, he had a life-altering experience as a patient which inspired him to become a healer, a chiropractor who is dedicated to relieving human suffering without drugs or surgery. Along the way he studied with numerous world-class physician/healers from around the world in healing arts ranging from chiropractic to herbology to homeopathy and acupuncture, all of which he uses to design a truly personalized treatment and home-care program for his patients.

 The techniques that he uses include Activator, Diversified, A-K, SOT, NET & Cranial Manipulation

 After serving in the Navy Submarine Service, he found himself in poor health, actually he felt like an old man with debilitating health conditions such as food sensitivities to most common foods, chronic sinusitis and irritable bowel syndrome. He was in his early 20’s, like most folks at the time he hadn’t heard of chiropractic and visited several medical doctors to try and resolve these health problems. One wanted to do surgery on his sinuses, another suggested an elimination diet which would have left him hungry all day, still another insisted that he would have to take several prescription medications for the rest of his life. Although he knew of no alternative, his intuition was telling him there must be a better way. Within a few months, he had met a couple who immediately suggested to see Dr. Peter Marsteller (D.C.), an elderly chiropractor/homeopath who was a legend in the area. He gave him some homeopathic remedies, a series of chiropractic adjustments, colonic irrigation therapy & some nutritional advice and literally within weeks he was breathing and eating and digesting about 80% better. Within a few months he was healthier than he had ever remembered being.

 The range of patients he has successfully treated over the years has been an hour-old infant to a 94 year-old man with scoliosis. Dr. Steven has treated elite athletes as well as pregnant women, teens with scoliosis & various types of pain syndromes, his real passion is helping all of his patients achieve high level wellness & give them the tools to maintain that well-being on going. To that end he employs a wide range of proven natural therapeutics & supplements to complement the office visits.

 Chiropractic’s first priority is to restore normal function to the nervous system, the body’s electrical system which “controls and coordinates all the systems in the body”. Though many people believe that chiropractic is primarily used to treat back pain (though they are the experts in treating pain), the original focus of chiropractic was healing the whole body….naturally via the nervous system.

Dr. Ryan, DC, Associate Chiropractor

Dr. Kevin Ryan grew up receiving chiropractic care in his hometown of Aurora, Colorado. When growing up, he knew that he wanted to spend his life helping people. Becoming a chiropractor was a perfect fit for him!

Experiencing his own back problems is what drove him to find ways to protect his back without drugs or surgery.

He graduated from Palmer College of Chiropractic in 1997. He has additional certifications in Advanced Biostructural Correction™, Applied Kinesiology and NIMMO technique.

In his spare time he enjoys spending time with his kids, playing guitar, participating in outdoor sports and watching the Broncos during game season!

Chandler Daily, Treatment Services Manager

Chandler was born and raised in Colorado. Her family moved to Florida in 2010 where she was first introduced into the medical field. Chandler attended a high school that had a medical program and this program allowed her to not only get her CNA certification but also to fall in love with medicine and helping people.

Chandler then attended Florida Atlantic University, where she obtained her Bachelor’s in Health Science with a concentration in Public, Global and Environmental Health. During her studies at University she found holistic medicine and preventive care to be her passion. Being a part of an interdisciplinary team and finding hobbies such as yoga further drove her desire to fully understand wellness.

In June of 2019, she decided that home is where the heart is, so she moved back to Colorado. Chandler was drawn to Keystone Health & Wellness because they have personalized treatment plans for each patient and treat the body as a whole and in a way that avoids medication and invasive procedures.  Becoming the Treatment Services Manager allows Chandler to work as the communication liaison between patients and providers.

In her free time, she enjoys reading, tending to her house plants, being outdoors, practicing yoga and mindfulness, cooking and being social. Chandler makes it a goal to try a new hobby each month and has a long list of little skills that just keeps growing.

Josh Mattingley, CPT | CNC Rehab Tech

Josh has completed the following certifications:

– Certified Nutrition Coach by the National Academy of Sports Medicine

– Certified Personal Trainer by the National Academy of Sports Medicine

– Basic Life Support Provider by American Heart Association BLS Program


Our Clinic Administration

Shawn Johonnesson, President

Shawn has 29 years of experience in business consulting and management.  He has successfully consulted and managed in South Africa, Canada and the United States in chiropractic, dental, entertainment, insurance, sales, banking, trucking, publishing and software industries. In 2007, Shawn and his family moved to Boulder, Colorado and began specializing in the management and consultation of chiropractic offices.  He was immediately brought on board a failing chiropractic office and promptly helped guide them to achieve their highest-ever numbers in patient visits, new patients and overall success which they carried forward for the next year and a half.

Following the improvement of several offices, Shawn decided to partner with a chiropractor and open his own office in 2013. In 2015, they decided to medically integrate, enabling them to broaden their range of services and to offer a more comprehensive approach to patient conditions. Since this time, the office has outgrown its previous facility, more than doubling in square footage.

Shawn has personally held and managed every administrative position in the clinic from front desk to insurance billing to marketer and case management. While there are other staff to perform these duties now, he personally enjoys continues to enjoy case management where he helps educate patients on our services and learning about solutions otherwise unknown. Shawn’s passion is helping people to do better in life. Shawn is married and a father of three children, one boy and two girls. He enjoys landscape photography and hiking.

Cassandra Johonnesson, Case Manager

Cassandra has spent most of her life in Los Angeles, California up until 2015 when she moved to beautiful Colorado.  She has 4 years of previous experience in writing and executing managerial and organizational programs for large numbers of staff.  She attended Hubbard College of Administration and became certified in their Effective Leadership course. 

Cassandra is now involved in building and perfecting the administrative structures within our clinic to help facilitate the best standard of care. When she is not typing up how-to manuals for the staff or administering team-building exercises, she is delivering one-on-one consultations with new patients to educate them on developing symptoms and solutions available from our providers. 

Nic Seaver, NMS | FNS, Office Manager

Nic Seaver’s passion for helping patients brought him to find his professional home at Keystone Health and Wellness Center. In his experience both working with patients and as a healthcare administrator, he has seen just how beneficial Keystone’s integrated approach is to the experience of every patient. He is a strong advocate for holistic medicine, as it directly looks to identify and solve medical problems without the use of risky pain killers that only cover-up the underlying situation. In addition to his neuro-muscular specialty, he is versed in insurance, and strives to ensure that any patient’s insurance is being utilized to its fullest to achieve stellar care.

Nic started his over 6 year career in physical healthcare working as a fitness advisor in Colorado Springs in July of 2013 after becoming a certified personal trainer, and received his fitness nutrition specialist certification in December of that same year. He became a coach for USA Weightlifting in April of 2015 after a year spent as a community athlete at the Olympic Training Center in Colorado Springs. In September of 2016 he transitioned to the medical side of physical health, working as the director of kinesiology at a large Colorado hospital. Nic loves using his experience gained from working with hundreds of patients and clients over thousands of hours to help people improve their day to day lives and overcome hardships.

Outside of the clinic Nic enjoys hitting the gym, learning about various scientific and historical subjects, spending time with and volunteering with animals including horses, dogs and cats. His biggest passion outside of healthcare is rugby, and he still plays minor league nationally. 

Shane Walker, Director of Public Contact

Shane has been working with us at Keystone Health and Wellness Center for over a year. He chose a career path in holistic medicine because he firmly believes it is an innovative industry. He has seen how this industry offers people who are suffering and in pain a chance to find a healthy solution that will improve their daily lives drastically. For him this is not just a typical nine to five work and then go home kind of job. It is so much more than that! He strongly believes in holistic medicine; he knows that we are making a difference in the community by pushing holistic medicine forward.

Shane received his Bachelor’s degree in Kinesiology from Colorado Mesa University in 2017. At Colorado Mesa University he became well versed in anatomical kinesiology, human anatomy, and body mechanics. Shane was initially involved with the physical therapy treatment team at our office. He was trained under the Advanced Medical Integration Model and served as a Rehab Tech where he worked with patients and supervised therapeutic exercises at our office. He is now taking on the important role of Community Relations Coordinator where he has the opportunity to engage with people from all over the community and promote our holistic health services.

In his free time Shane loves to watch the Rockies and Broncos play. In the summer he enjoys fly fishing and going on adventures in the mountains. His passion is snowboarding and in the winter he enjoys going snowboarding every weekend.

Find Your Pathway to Health & Wellness