Orthopedic & Spine Institute

Meet Our World-Class Surgeons and Providers

With the introduction of the Orthopedic & Spine Institute, UMC has built an unparalleled team, bringing together our community's most respected orthopedic surgeons and providers to deliver the state's most advanced level of care. 

Dr. Erik Kubiak 

Trauma Injury Repair and Joint Replacement

Dr. Erik Kubiak is a board-certified Orthopedic surgeon specializing in trauma injury repair, joint replacements and hip preservation. As the Medical Chief of the UMC Orthopedic & Spine Institute, Dr. Kubiak provides comprehensive care for patients of all ages, focusing on complex trauma cases and joint reconstructions. 

He earned his medical degree from the University Of Washington School Of Medicine, completed his Orthopedic Residency at the Hospital for Joint Diseases in New York City, and pursued a Trauma Fellowship at Harborview Medical Center in Seattle.

With over a decade of experience, Dr. Kubiak has been at the forefront of integrating artificial intelligence in surgery, pioneering innovative techniques to enhance precision and reproducibility. His passion for advancing the field also extends beyond the operating room. He is a Professor and Chair of the Orthopaedics Department at the Kirk Kerkorian School of Medicine at UNLV, where he mentors the next generation of orthopedic surgeons. Additionally, he frequently travels abroad to teach complex surgical methods.

Outside of medicine, Dr. Kubiak is an avid outdoorsman who enjoys fishing and mountain bike racing. He is also a retired rock-climber. 

Dr. Abby Howenstein

Trauma Surgery and Pediatric Orthopedic Surgery

Dr. Howenstein is a board-certified orthopedic surgeon who specializes in advanced care of fractures for patients of all ages. She has additional training to manage complex orthopedic cases for children with traumatic injuries. Dr. Howenstein takes pride in seeing her patients get back to doing what they love after recovering from an injury. 

Dr. Howenstein attended medical school at the Indiana University School of Medicine, followed by an orthopedic surgery residency at the University of Utah. She then completed two fellowship programs: one in orthopedic trauma surgery at Carolinas Medical Center and the other in pediatric orthopedic surgery at North California Shriners Hospital at UC Davis. 

When not caring for patients, Dr. Howenstein enjoys hiking with her dogs, weight training and practicing Jiu-Jitsu.

Dr. Alexander Mayers 

Trauma Surgery

Biography coming soon!

Dr. Andrea Attenasio 

Trauma Surgery and Reconstruction Surgery

Biography coming soon!

Dr. Angelina Vera

Sports Medicine Surgery

Dr. Vera is a board-certified, fellowship-trained orthopedic surgeon who specializes in sports medicine, arthroscopy, and treating injuries to the shoulder, hip, knee and ankle. She is dedicated to the prevention and management of sport and dance-related injuries. 

Dr. Vera earned her bachelor's degree in Sports Injury Management from the University of Nevada, Las Vegas. She subsequently attended the University of Nevada School of Medicine for her medical doctorate. She completed her residency in orthopedic surgery at Houston Methodist Hospital and completed a fellowship in Orthopedic Sports Medicine at Mayo Clinic in Arizona.

Dr. Vera worked as a professional dancer, instructor and choreographer for more than 10 years before, during and after her undergraduate career.

Dr. Anthony Bratton

Sports Medicine Surgery

Dr. Anthony Bratton is a board-certified orthopedic surgeon and a trusted leader in sports medicine, dedicated to restoring mobility and empowering patients to reclaim their active lifestyles. Specializing in knee, shoulder, elbow, ankle, and hip injuries, Dr. Bratton combines advanced surgical and non-surgical treatments and compassionate care to deliver exceptional outcomes.

Dr. Bratton received his medical degree from the University of Chicago Pritzker School of Medicine, followed by an orthopedic residency at Loyola University Medical Center and an elite Orthopaedic Sports Medicine Fellowship at the University of Texas Health Science Center at Houston/Baylor College of Medicine.

Dr. Bratton advances sports medicine through research and mentorship, serving as a faculty member at the Kirk Kerkorian School of Medicine at UNLV and head orthopedic surgeon to the Henderson Silver Knights as well as UNLV Men’s and Women’s Athletics. 

In his free time, Dr. Bratton enjoys golfing and fishing. Above all, he cherishes spending time with friends and family, grounding him in the values of connection and care that define his approach.

Dr. Benjamin Hansen

Total Joint Surgery, Hip and Knee Replacements

Dr. Hansen specializes in hip and knee replacement surgeries, using groundbreaking clinical technology to provide his patients with the best possible results and improved quality of life. He takes pride in improving access to highly specialized care in Southern Nevada. 

Dr. Hansen is board-certified by the American Board of Orthopaedic Surgery and a Fellow of the American Academy of Orthopaedic Surgeons. He also serves as an oral board examiner for the American Board of Orthopaedic Surgery certification exam. He completed his surgical residency training at the University of Utah, followed by a fellowship at Duke University in complex primary and revision hip and knee reconstruction. 

His hobbies include CrossFit and spending time with his family. A dedicated husband and father of three, he plays an active role in his children's many activities, including baseball, gymnastics and soccer.

Dr. Brandon Romero

Shoulder and Elbow Surgery

Dr. Romero specializes in comprehensive shoulder and elbow care, treating tendon and ligament tears, fractures and arthritis. Growing up in Henderson, he takes pride in bringing high-quality orthopedic care to his hometown. 

Dr. Romero completed his medical residency at the Kirk Kerkorian School of Medicine at UNLV, followed by fellowships at the University of Pennsylvania and hospitals in Spain and Monaco. He is one of only three fellowship-trained shoulder and elbow surgeons in Southern Nevada and serves as the site director for the American Shoulder and Elbow Surgeons Committee on Prosthetic Joint Functions, in addition to teaching orthopedic residents at UNLV. 

As a former college baseball player, Dr. Romero now enjoys coaching his three sons on the field. He also likes to travel with his family to see different sporting events, including football, hockey and BMX racing.

Dr. Brock Wentz  

Trauma Surgery

Biography coming soon!

Dr. Casey Roehr 

Trauma and Reconstruction Surgery

Biography coming soon!

Dr. Drew Iman 

General Orthopedics and Joint Replacements

Dr. Iman specializes in joint replacement and the treatment of general orthopedic conditions. He enjoys helping patients get back to enjoying the activities they love. 

Having earned his Osteopathic Medical degree from Des Moines University in Iowa, Dr. Iman completed a 5-year residency at St. John Providence Health System in Detroit, Michigan. He went on to complete fellowship training in Adult Reconstruction at the Mayo Clinic in Jacksonville, Florida. Dr. Iman is a diplomate of the American Academy of Orthopaedic Surgery, American Osteopathic Academy of Orthopaedics, American Osteopathic Association, and is board eligible. 

As a native of Denver, Dr. Iman enjoys many outdoor sports, including skiing, snowboarding, hiking, and mountain, and climbing. Now, he is excited to call Nevada home and is eager to explore all this beautiful community has to offer. In his free time, he enjoys lifting weights, playing several musical instruments, spending quality time with his wife, Susan, two dogs (for now), family, and close friends.

Dr. Eugene Libby 

Traumatic Injury Repair, Sports Medicine and Fracture Care 

Dr. Libby is a board-certified general orthopedic surgeon with expertise in traumatic injuries, sports medicine and fracture care. He loves helping patients feel like themselves again!

Dr. Libby graduated from Ohio University College of Osteopathic Medicine. He stayed in Ohio to complete his residency at Doctor’s Hospital of Stark County and a fellowship at Grant Medical Center. 

Dr. Libby enjoys hiking and traveling. He finds joy in experiencing new parts of the United States and other countries. 

Dr. Janel Pietryga

Trauma Injury Repair and Fracture Care 

Dr. Pietryga specializes in comprehensive care of traumatic injuries for patients of all ages, with a focus on acute fractures. Dr. Pietryga is motivated to help patients pave a positive road to recovery with prompt and compassionate care. 

Dr. Pietryga graduated from the University of New Mexico School of Medicine, followed by her residency in orthopedic surgery at the Kirk Kerkorian School of Medicine at UNLV. She completed an Orthopedic Trauma Fellowship at the University of California San Diego in 2023, specializing in complex pelvic and periarticular fracture care and minimally invasive surgery techniques.

In her free time, Dr. Pietryga enjoys Olympic-style weightlifting and creating her own porcelain artwork. 

Dr. Jenifer Powers  

Pediatric Orthopedic Surgery

Dr. Jenifer Powers is a board-certified pediatric orthopedic surgeon dedicated to providing compassionate, comprehensive care to children and adolescents with congenital conditions as well as traumatic injuries. A Las Vegas native, Dr. Powers feels honored to serve the community that raised her, offering expert orthopedic care tailored to the unique needs of growing children.

Dr. Powers earned her undergraduate degree from California Lutheran University before returning to Nevada to attend medical school at the University of Nevada School of Medicine. She went on to complete her orthopedic surgery residency at the University of Utah. Following residency, she pursued subspecialty fellowship training in pediatric orthopedic surgery at Texas Children's Hospital—one of the top-ranked children's hospitals in the nation—where she gained advanced expertise in treating complex pediatric conditions and stayed on as faculty there for almost six years before returning home.

Dr. Powers’ path to orthopedics began as a competitive gymnast, where her firsthand experience with sports-related injuries sparked a lifelong passion for musculoskeletal health. Today, she brings that same dedication, discipline, and empathy to her patients and their families.

Outside of her practice, Dr. Powers enjoys spending time with her husband and their three children. As a family, they love exploring the outdoors, skiing, and getting creative with arts and crafts. Whether in the clinic, the operating room or the community, Dr. Powers is committed to making a positive difference in the lives of the children she cares for.

Dr. Karen Nelson  

Traumatic Injury Repair 

Dr. Nelson is an orthopedic surgeon specializing in traumatic injuries and total joint replacement and advanced joint reconstruction, with a particular focus on complex pelvic fractures. She is deeply committed to supporting patients through some of their most challenging moments and takes great joy in celebrating their recoveries. 

Dr. Nelson graduated from Touro College of Osteopathic Medicine, followed by an orthopedic surgery residency at Henry Ford Malcomb Hospital in Michigan and a fellowship in orthopedic trauma at UMC. Dr. Nelson also serves as an Assistant Professor of Orthopedic Surgery at the Kirk Kerkorian School of Medicine at UNLV. Additionally, she is the Assistant Program Director for the UMC Orthopedic Trauma Fellowship Program.

Outside of medicine, Dr. Nelson enjoys spending quality time with her family and exploring the outdoors through backpacking, snowboarding, biking and running.

Dr. Mark Sylvain 

Trauma Injury Repair

Dr. Sylvain is a board-certified orthopedic trauma surgeon who also specializes in joint reconstruction. He is driven by his desire to help patients get back on their feet after traumatic injuries. 

Dr. Sylvain is a third generation Las Vegas physician. He graduated from the University of Nevada School of Medicine in Reno, followed by a residency at Wayne State University and a fellowship at the University of California San Diego. 

In his free time, Dr. Sylvain loves spending time with his family.

Dr. Richard Wulff

Trauma Injury Repair and Joint Replacements

Dr. Wulff specializes in surgeries to repair complex traumatic injuries, including fractures, dislocations, tendon and ligament repairs, and nerve injuries for patients of all ages. He also treats athletes with sports-related injuries and total joint arthroplasty. Dr. Wulff takes pride in offering the specialized care patients need to regain function and improve their quality of life after a traumatic or life-changing injury. 
 

Dr. Wulff is board-certified by the American Board of Orthopaedic Surgery. He completed medical school at Medical College of Georgia at Augusta University, while completing his residency at University of Missouri, Kansas City. 
 

In his free time, Dr. Wulff is an avid traveler and enjoys hiking. He has been to numerous countries all over the world. 

Dr. Sukanta Maitra

Adult and Pediatric Spine Surgery

Dr. Maitra is a board-certified spine surgeon who specializes in both simple and incredibly complex procedures for patients of all ages suffering from degenerative issues, sports injuries, traumatic injuries, tumors, infections and curvatures of the spine. He takes pride in treating his patients like family and taking a holistic approach while providing the highest level of spine care in Nevada.

Dr. Maitra attended Medical School at Albany Medical College in New York, followed by an Orthopedic Surgery Residency at UC Davis Medical Center and an Orthopedic Spine Fellowship at the University of Utah. He is passionate about educating the next generation of surgeons through his role as Associate Program Director for the Orthopaedic Surgery Residency Program at the Kirk Kerkorian School of Medicine at UNLV.

When he is not performing life-changing surgeries, Dr. Maitra enjoys playing golf, watching Formula 1 races and spending time with his family.

Angela Greenhalgh, APRN

Spine Specialist 

Angela Greenhalgh is a board-certified Advanced Practice Registered Nurse (APRN) who specializes in treating patients for a full range of spine issues, including degenerative issues and traumatic injuries. She also has extensive knowledge in treating other orthopedic conditions in the shoulders, knees, hips, hands and feet. 

With a passion for healing, Angela has extensive experience working as a nurse practitioner and managing orthopedic practices. She enjoys relieving pain and promoting wellness for her patients through a comprehensive, research-based and collaborative approach. 

Angela is an outdoor enthusiast and frequent visitor to U.S. National Parks. She enjoys hiking and traveling to new places. 

Laura Rodriguez, PA-C  

Total Joint Specialist

Biography coming soon!

Robert Wilson, APRN

Orthopedic Specialist

Robert Wilson is a compassionate Advanced Practice Registered Nurse (APRN) who works alongside orthopedic patients to build comprehensive care plans that fit their specialized needs. Robert believes in a hands-on, collaborative approach with patients to help assess what treatments, medications and therapies are best for each patient before surgery. 

Robert received his Master of Science in Nursing from Touro University Nevada. Driven by his desire to help others, Robert has been caring for patients in Las Vegas for nearly 15 years, with experience in UMC’s Adult Emergency Department and UMC’s Level I Trauma Center. 

Outside of work, Robert is passionate about staying physically fit and exploring new places through travel. 

Sophia Cabrera, NP 

Orthopedic Specialist

With more than 17 years of dedicated clinical experience, Sophia Carbrera is a highly skilled and compassionate Orthopedic Nurse Practitioner who is committed to delivering exceptional patient care. Sophia primarily provides care to patients with traumatic orthopedic injuries, as well as general orthopedic conditions, including degenerative musculoskeletal conditions and acute musculoskeletal injuries.  

Sophia holds a Bachelor of Science in Nursing and a Master of Science in Nursing with a family Nurse Practitioner specialization from Roseman University. Her extensive background includes 15 years of specialized nursing experience in intensive care unit settings, where she developed expertise in managing complex, acute cases and coordinating multidisciplinary teams.   

During her free time, Sophia enjoys weight training and meditation. She believes both practices deeply support physical health, mental clarity and overall well-being, which are essential for providing the best care to her patients

Trang Truong, NP

Orthopedic Specialist

Trang Truong is a dedicated orthopedic nurse practitioner who specializes in treating patients with injuries related to physical activity and sports participation. She is motivated by her desire to help patients improve their quality of life and ease their pain. 

Trang holds a Bachelor of Science (BSN) from Rutgers University and a Master of Science in Nursing (MSN) from the University of Medicine and Dentistry of New Jersey. 

When she is not helping patients, Trang loves to travel to new places, learn about new cultures and hike outdoors.