Mountain Orthotics & Prosthetics Services, Lake Placid ~ Plattsburgh


Jeff Erenstone CPO
Owner, Head Clinician ~ Lake Placid
ABC Certified Prosthetist/Orthotist

I, Jeffrey Erenstone, am the primary clinician of Mountain Orthotic & Prosthetic Services. Locally born and raised, I am excited to return to the area to fulfill this health care niche. After earning a Bachelors of Science in Biology from the University of New Hampshire, I completed a Post-Bachelor Orthotic Practitioner Certificate program at Century College in White Bear Lake, Minnesota. I completed my Orthotic Residency at Northwest Orthotics and Prosthetics in Provo, UT where I continued to practice as a Certified Orthotist for several years. In 2006, I completed the Newington Prosthetic Certificate Program through the University of Connecticut. This led me to a residency with Mike Amrich CPO FAAOP of Boston Brace at Children’s Hospital in Boston, MA. Following the completion of my prosthetic residency, I worked as an orthotic design consultant for Spinal Technology in Yarmouth, Massachusetts. I have now returned to the North Country to open my own practice.

Through my training, I have gained specialized experience with spinal and lower extremity bracing, sports medical care, and treatment of traumatic and degenerative neurological conditions. In prosthetics, I have worked extensively with pediatric and traumatic amputees. I am a core staff member for Camp Ability, which is a summer camp for children with limb loss, as well as a volunteer for the Extremity Games, a competition for athletes with physical limitations. In time, I would like my practice to develop as a center of excellence for adaptive athletes. I focus my care on treating the whole patient and not just their amputation. I have been trained as an Amputee Supporter by the Amputee Coalition of America and invite your patients to contact me with any concerns. I would like to help them through their emotional transition, whether or not they intend to pursue my professional services.

Alex Trumper

Alex Trumper
Owner, Head Clinician ~ Plattsburgh
ABC Certified Prosthetist/Orthotist

I am excited to join the Mountain O & P team as the Practice Manager at the Plattsburgh office. I grew up in a suburb of Montreal, Quebec, Canada. In 2003 and 2006 respectively, I completed my Bachelor's degree in Kinesiology and a Master of Science degree in Biomechanics at McGill University. At this time, I decided to pursue the field of Orthotics in order to help individuals with injuries or diabilities. In 2007, I completed the Northwestern University Orthotics program and completed a 6 month research resident internship and 1 year Orthotic residency with Scheck and Siress, Chicago’s largest Orthotics and Prosthetics provider. I returned to Northwestern University to complete the prosthetic portion of my education in 2008 and transition into my 1 year prosthetic residency. I was fortunate to be have been awarded several scholarships (Gunther Gehl Scholarship, Dale Yasukawa Memorial Scholarship, named Best of the Resident Research series, and the Larry Lange travel award) for my resident research work and contributions to the field of Orthotics and Prosthetics. These awards allowed me to travel to Zacapa, Guatemala with the range of Motion Project (ROMP) to provide prosthetic care to patients that would not otherwise have access to these services. It was a truly amazing experience! I continued my career in Orthotics and Prosthetics with Scheck & Siress until July 2015. After 9 great years in Chicago, my wife and I along with our two children decided to move back closer to our family in Montreal. The North Country was naturally a great fit for our lifestyle as we enjoy the outdoor activities such as hiking, biking and skiing.

Chris Poulin

Christopher Poulin, C.Ped, CFo
ABC Certified Orthotic Pedorthist (C.Ped)
ABC Certified Orthotic Fitter (CFo)

Attended SUNY Canton for Occupational Therapy Assistant worked for AMC in Lake Placid at AMC Uihlein as a COTA for 3 years when the opportunity arose to work for Mountain O and P, I made the career shift to a Certified Orthotic Fitter, and then to further my education and to better serve the area became a Certified Pedorthist (C.Ped) through the Robert Palmer Institute in Elwood, IN.

Duties: Patient care, orthotic fitting and fabrication, compression garments, diabetic and orthopedic custom and off the shelf shoes, shoe modification, knee orthoses, foot orthotics, shipping and receiving, lab maintenance and anything else that needs doing.

Steve Halloran

Steve Halloran CFo
ABC Certfied Orthotic Fitter (CFo)
Prosthetic Peer Advisor

Steve grew up near Latham, NY, joined the Navy, and then graduated Magna Cum Laude from NYS Ranger school in Wanakena, NY. He now lives in Westport, NY with his three sons and his wife Mary, who is Rural Physician. After numerous years as a Forestry Services Contractor, Steve lost a leg due to a traumatic accident and become involved in the prosthetics industry. Steve's duties include technical work fabricating orthotics and prosthetics, and serving as an orthotic and prosthetic assistant.

And as an amputee and Certified Peer Adviser, Steve also provides first hand insight to patients on what to expect, how to get the most of their prosthetic, and how to continue to live life to its fullest.

"I was naturally drawn to this industry. I love learning about the latest advancements, and I very much enjoy helping people with something that I went through myself."


Michelle Swanston
ABC Certified Orthotist
Resident Prosthetist

I am in my orthotic residency with Mountain Orthotic and Prosthetic Services. I have interned with this great group of practitioners in the past, and was pleasantly welcomed onto the staff in late May 2015. I have matriculated through the University of Hartford B.S. /M.S.P.O. Program in Hartford, Connecticut, where I received a Bachelors of Science in December of 2013, and later a Masters of Science in Prosthetics and Orthotics in May 2015. I am a local of the North Country who grew up on a family-owned / operated dairy farm and have a passion to work with people. I am eager and humbled to be able to share what I have learned as well as expand my knowledge with Mountain O & P and with those I encounter throughout my career. It is nice to come back home!

Greg Popp

Greg Popp
ABC Certified Orthotist, Prosthetist-R


Owner, Practice Manager

Duties: Billing & Compliance


Senior Administrator ~ Lake Placid


Senior Administator ~ Plattsburgh


Administrator ~ Plattsburgh

Lab Manager


The youngest staff members
Morale Managers
Duties: Being adorable