Meet Us

Operation Walk Boston was founded in 2007 to improve the quality of life for impoverished patients through the direct and indirect delivery of orthopedic health care

Meet Our Founder

Meet Operation Walk Boston's founding member


Thomas S. Thornhill, MD, is Chairman Emeritus of the Department of Orthopedic Surgery at Brigham and Women's Hospital (BWH) and the John B. and Buckminster Brown Professor of Orthopedics at Harvard Medical School Thornhill graduated Phi Beta Kappa from Williams College and Alpha Omega Alpha from Cornell Medical School.  He served as a medical intern and resident at Peter Bent Brigham Hospital followed by two years in the NIAMD at the National Institutes of Health.  Following six months of training in general surgery in Cambridge and Newmarket, England, he entered the Harvard Combined Orthopedic Residency Program.  He served as chief resident at Massachusetts General Hospital, followed by a fellowship in arthroplasty at Robert Breck Brigham Hospital.  Thornhill became chair of the Department of Orthopedic Surgery at the New England Baptist Hospital and the division of orthopedics at the New England Deaconess Hospital in 1995.  From 1996 to 2015, he has served as chair of the Department of Orthopedics at Brigham and Women's Hospital.  Thornhill maintains an active practice in total hip, total knee, total shoulder, and total elbow arthroplasty.  His research interests have ranged from the study of immune reactions in arthritis and following joint arthroplasty to joint design and outcomes following joint replacement.  With a combined interest in outcome measures and international orthopedics he and colleagues Jeffrey Katz, MD, MSc, and Elena Losina, PhD, founded the BWH Orthopedic and Arthritis Center for Outcomes Research (OrACORe) in 2006.  The following year he founded Operation Walk Boston to bring surgical expertise to help underserved patients suffering from severe hip and knee arthritis in the Dominican Republic.

Meet Our Management Team

Meet Operation Walk Boston's dedicated leaders

The Santo Domingo Team:


Luis Alcantara Abreu, MD, is the founding resident of the Orthopedics Surgery Residency Program at Armed Forces Central Hospital , a first-of its-kind military hospital in the Dominican Republic (DR).

In 1994, at the Hospital Ortopedico Infantil de Caracas, Venezuela, Alcantara was the first PGY fellow from outside the country.  Alcantara earned his MD in 1996 and began his career as an orthopedic surgeon in 1997 at Hospital General de la Plaza de la Salud (HGPS), a one-of-a-kind institution founded in the Dominican Republic that same year.

In 2002, he was appointed head of the HGPS Orthopedics Department.  Recently, he stepped down to found and chair the Joint Replacement Department, a first for both the hospital and the Dominican Republic.  Today, Alcantara's practice is fully dedicated to hip and knee replacement surgery.

Alcantara is a member of societies including the international affiliate of the American Association of Orthopedic Surgeons and the Sociedad Dominicana de Ortopedia y Traumatologia.  He is medical adviser for the United States Diplomatic Mission in the DR.

Since 2008, Alcantara has served as the medical coordinator for Operation Walk Boston at HGPS.  He has helped publish nine academic articles on outcome studies made possible by the Operation Walk experience.

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Desirée Diez Portela, MSc, is a project manager with more than 10 years of experience in the nonprofit health sector.  Since 2008, she has served as head of the Projects Management Department at Hospital General de la Plaza de la Salud (HGPS) in Santo Domingo, Dominican Republic. Diez earned her Bachelor of Arts degrees in both international development and public communications from American University in Washington, DC and her Masters in Science in health, community and development from the London School of Economics and Political Science in the United Kingdom.  She has experience in diverse healthcare projects that range from health communications and promotion to administrative, engineering, IT, and other interdisciplinary projects. Diez is also responsible for international health alliances at the HGPS—which include academic and social giving activities with renowned healthcare partners like Operation Walk Boston.  She is a health advocate interested in global health parity and public health issues, especially health financing, health literacy, and access to treatment.  Diez speaks fluent Spanish, English, French and Portuguese.

The Boston Team:

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Barbara Manners Aggouras, NP-C, is a nurse practitioner for the Department of Orthopedics at Brigham and Women’s Hospital.  Since October 2010 she has managed patients for the orthopedic team on the in-patient units.  Before assuming her current role, she served as the clinical nurse educator for three years and as staff nurse for five years. 

Aggouras earned her associates degree in 1996 and her masters degree, with honors, in 2007, both from Regis College.  She is certified as a Family Nurse Practitioner through the American Academy of Nurse Practitioners.

Since 2009, she has participated in Operation Walk Boston, taking on the role of nurse coordinator for the mission in 2010.  Aggouras has offered training and classes to nurses at Hospital General de la Plaza de la Salud and has worked closely with the nurses of our guest hospital on the mission to elevate the practice of nursing.  Operation Walk Boston is near and dear to her heart and the experience has been life changing.


Forrest H. Schwartz, MD is a fourth-year resident in the Harvard Combined Orthopedic Surgery Residency Program.  In 2007, he graduated from Stanford University with a B.A in Human Biology, and a concentration in International Health and Crisis Management. He earned his medical degree from Washington University in Saint Louis in 2012 and is currently completing his Orthopedic Surgery residency at Harvard Medical School. Forrest is currently applying for a fellowship in Adult Hip and Knee Reconstruction, and hopes to establish a practice focusing on complex revision arthroplasty after he finishes his training.


Roya Ghazinouri, PT, DPT, MS graduated from Tehran University of Medical Sciences with a bachelor’s degree in physical therapy in 1993. She then came to the US to receive her master’s degree and doctorate in physical therapy from MGH Institute of Health Professions in 1999 and 2007, respectively.  She is currently the Director of Operations for Center for Healthcare Delivery Sciences ( at Brigham and Women's Hospital

Ghazinouri has more than 20 years of clinical and managerial experience at large academic medical centers in Boston and New York.  Since 2008 she has served as the chief operating officer for Operation Walk Boston.  In this role, she is responsible for coordinating all aspects of this annual mission, working closely with the host institution in Dominican Republic to ensure sustainability of the program. 

Ghazinouri is the graduate of Harvard Business School Leadership program.  She has led and collaborated with various providers across BWH to implement numerous quality and process improvement initiatives.


Jeffrey N. Katz, MD, MSc graduated from Princeton University in 1980, attended Yale Medical School, and completed a medical internship and residency at Yale-New Haven Hospital and a rheumatology fellowship at Brigham and Women’s Hospital (BWH).  He earned his master’s degree in 1990 at Harvard School of Public Health.  Dr. Katz is currently professor of medicine and orthopaedic surgery at Harvard Medical School and professor of epidemiology and environmental health at Harvard School of Public Health. 

Katz has focused his research on the evaluation and outcomes of musculoskeletal disorders including carpal tunnel syndrome, lumbar spinal stenosis and osteoarthritis, and lower extremity joint replacement.  He has developed measures of functional status and symptom severity for several conditions including carpal tunnel syndrome and lumbar spinal stenosis.  Katz has led studies documenting the influence of surgeon and hospital volume on outcomes of total joint replacement.  Most recently, he led the MeTeOR Trial of surgical vs. rehabilitative approaches to the problem of meniscal tear in the setting of osteoarthritis.

Katz is the director of the Orthopaedic and Arthritis Center for Outcomes Research in the Department of Orthopaedic Surgery and Division of Rheumatology, Immunology and Allergy at BWH.  He is principal investigator of the Brigham Multidisciplinary Clinical Research Center (an NIH  P60 Center) and the MeTeOR Trial (a seven center RCT of the efficacy of arthroscopic partial meniscectomy) and co-principal investigator of a NIAMS-funded T32 clinical research training program.  He also serves as deputy editor for methodology of the Journal of Bone and Joint Surgery and on the board of the Osteoarthritis Research Society International. 


Paul Laemmle, RN, brings more than 30 years of nursing practice to his role as operating room coordinator for Operation Walk Boston.  He earned degrees in nursing and biology from The University of Texas at Austin.  A founding member of Operation Walk Boston, he also currently serves as a staff nurse in orthopedics at Brigham and Women’s Hospital.



Debbie Pitts is a registered nurse who started her career in health care as a lab technician in the US Army.
She then went on to receive her nursing degree from Somerville Hospital School of Nursing.  Her nursing experience spans across the continuum of care delivery and in many clinical settings in the US. Since 2000, she has been working at BWH as an Operating Room Nurse with the Orthopedics Department.  In addition to her vast clinical experience, Debbie brings the discipline, organization and diligence of a military training.  Debbie has been Operation Walk’s Cargo Coordinator since 2009.  She has helped the mission maintain a cost effective and standardized approach to accrual and use of patient/surgical cargo.  She is passionate about volunteer work and in addition to Operation Walk Boston, has participated in numerous other international medical missions.

Meet Our Board of Directors 

The members of our board are esteemed medical professionals and colleagues


Mercedes Concepcion, MD, was born and raised in the Dominican Republic.  She earned her MD at Santo Domingo University and worked at Padre Billini Hospital, also in Santo Domingo, before receiving her licensing. She then completed a transitional internship at Queen Elizabeth Hospital in Montreal, Canada, and a five-year program, including one year of internal medicine, at McGill University. She also completed six months of neuro-anesthesia and six months of subspecialties, including regional anesthesia, at Notre Dame Hospital in Montreal.

Concepcion served as an anesthesiologist at the Robert Breck Brigham Hospital (a predecessor of BWH) and, more recently, as the director of orthopedic anesthesia at BWH, where she started a regional anesthesia practice in orthopedics and later extended the service to general and thoracic surgeries.

At BWH, Concepcion created a regional anesthesia fellowship, the first in the country.  She also established BWH’s post-operative pain service.

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Dr. David A. Mattingly is clinical chair of Orthopedics and surgeon in chief at New England Baptist Hospital (NEBH).  Mattingly also holds an academic appointment as clinical assistant professor in the Department of Orthopedic Surgery at Tufts University School of Medicine.

A well-recognized writer and lecturer with numerous publications in orthopedic literature, Mattingly specializes in total joint replacement and revision surgery of the hip and knee.  He has been on many of Operation Walk Boston’s missions and provides surgical care to patients in the Dominican Republic.


Dr. Richard D. Scott is an Orthopedic Surgeon at New England Baptist Hospital (NEBH).  Scott holds academic appointments as professor of orthopedic surgery at Harvard Medical School and as lecturer of surgery at University of Arizona College of Medicine. 

An internationally recognized expert in partial and total knee replacement, Scott has made significant contributions to the understanding of disease processes and operative techniques in arthritic conditions.  He earned his medical degree from Temple University School of Medicine.  Following his orthopaedic surgery residency with the Harvard Combined Orthopedic Residency Program, he completed an orthopaedic surgery fellowship at Brigham and Women's Hospital.  Since 2008, Scott has participated in numerous Operation Walk Boston missions and has made significant contributions to the team.



Dom Dinardo is the president/owner of DJD medical and a distributor for DePuy Synthes.  He has been involved with DePuy for the past 31 years and has held a variety of positions from sales to marketing up until 1991 when he started DJD Medical. Dom has been involved with Operation Walk Boston since its inception in 2007.


A dedicated team of volunteer medical professionals coordinate our missions each year, here are some of their stories.

John Ready, Orthopedic Surgeon: “It has been a privilege to join Operation Walk and become a member of the team and family. It truly does “take a village” and we see that in the DR on a daily basis. Every member has an important function and works hard to avoid letting anyone down. It is most gratifying to see the look on the faces of the patients and families as they embark on the journey to restore function and alleviate pain. We are so lucky to be part of this transformation.”


Dom Dinardo, President of DJD Medical: "Operation Walk Boston has been a one of the most rewarding experiences in my professional and personal life, having the opportunity to treat patients who would have never had the ability to have receive a joint replacement."


Archana O’Neill, Anesthesiologist: “I have been going on the Operation Walk mission for the past 3 years. It has been an amazing experience! What makes the mission so special is the people. The procedures make such a difference in the lives of our patients, and I really appreciate the gratitude and the spirit that they show. In addition, I love the camaraderie among the numerous volunteers both from the United States as well as the Dominican Republic. It is a real team effort!


Daniela Lazea, Anesthesiologist: “First time I went to DR I was a resident and I couldn't have had a better and happier experience. I worked hard but every second I was reminded of how amazing the people can be. A warm hug and a smile are the most important rewards!


Christine Coulthard-Schlosstein, Nurse:  “I have been a member of the Op Walk-Boston team for 7 years as a nurse in the PACU/Pre-op area. I continue to be humbled by the appreciation shown by the Dominican patients and staff. To see a patient walk one day after surgery who may not have walked in years is an amazing experience!


Christina Foley, Nurse: “It has been both an honor and a privilege to have had the opportunity to travel to Santo Domingo and participate in Operation Walk Boston for the past three years. Our Dominican patients are some of the most resilient, ambitious and warm hearted people I have ever had the privilege of providing nursing care to. These patients and their families are full of love and gratitude as evidenced by their sweet smiles and proud postoperative strides. It is a true honor to work alongside such an incredible multidisciplinary team and to provide care to these beautiful people.


Fiona Franklin, Nurse: “I have been going on Operation Walk since 2010, and it has been an amazing experience for me each year. It is a wonderful feeling to be able to be part of a team that is able to give people the gift of walking back. My first year on this trip I had just turned 24, it was quite shocking to me to be replacing hips and knees on men and women younger than I was, but on our last day watching them be able to get up and walk was beautiful, it brought me to tears It truly is an amazing experience to watch someone who has been wheelchair bound for years get up and walk, it is life changing."


Ellen Silvius, Nurse: “As a nurse, I consider it a privilege to care for patients wherever they may reside. It only raises my level of empathy and compassion to be in a position to care for patients whose lives do not afford them access to reasonable healthcare. It is debatable who benefits more from this collaboration; the patient with their new joint or those who are lucky enough to be a part of their medical metamorphosis. I am humbled to be a part of helping such an inspiring group of patients and to work with such a gifted group of providers.”


Anne McDonnell, Pharmacist: "Operation Walk has been an amazing experience for me. Personally, I enjoy working with this amazing group of people to make life better for those in need."


Carolyn Beagan, Physical Therapist: “I have been with Operation Walk since 2008. One of the best parts of each trip is having our patients from previous years walk into post-op clinic pain free with smiles on their faces, and stories of what they have done since they had their total knee or hip replacement. It is an event that you could mistake for a big family reunion each year.”


Stephanie Lew, Physical Therapist"This will be my second year volunteering for Operation Walk. It was so inspiring to work with such motivated patients, and to collaborate with such a compassionate team of Dominican and American health professionals. I’m grateful for the relationships I made, and am looking forward to seeing everyone again soon!"


Jillian Ng, Physical Therapist: “This year's trip will be my 5th Op Walk mission! Each year I look forward to this amazing week of teamwork to make a difference in the lives of our patients while also learning about their beautiful culture.


Annie Yingling, Physical Therapist: “Last year was my first year volunteering with Op Walk and I loved every second of it. The patients and the teamwork make the experience so incredibly special. I feel extremely lucky to be a part of Op Walk Team and cannot wait for 2015!


Josh Eaton, Implant Representative: “This will be my 7th OpWalk Mission, and I can't wait to return to the warmth and generosity of the Dominican people. I am always impressed with the strong sense of family I see when our patients are going through their treatment.”