David Weiss, DO
Dr. David Weiss is a fellowship-trained, interventional pain physician specializing in non-surgical musculoskeletal care for patients who are unsuitable for surgery or have not found sufficient relief from surgical interventions.
Collaborating closely with the surgeons at OIP, Dr. Weiss provides comprehensive musculoskeletal care, utilizing innovative solutions such as neuromodulation and advanced modalities to alleviate chronic pain. He is adept at treating conditions like neuropathy, joint pain (including shoulder, hip, and knee), neck and back pain, and conducting spinal cord stimulator trials. His practice encompasses interventional pain services for both diagnostic and therapeutic purposes.
Renowned for his excellent communication and collaborative care management, Dr. Weiss is dedicated to helping patients return to doing what they love.
Dr. Weiss enjoys traveling and exploring new cuisines, movies, and old movie theaters when he’s not at work. His interests reflect his passion for life and commitment to helping patients return to theirs.
Robyn Daiber, D.O.
Dr. Daiber was born and raised in Hummelstown, PA where she graduated from Lower Dauphin high school. She received her bachelor’s degree in Pre-Health from Shippensburg University and then continued to earn her medical degree at Philadelphia College of Osteopathic Medicine. Dr. Daiber completed her Orthopedic Surgery residency at UPMC Pinnacle in Harrisburg, the same hospital where she once volunteered at and worked as an emergency room technician prior to medical school. She then went on to specialize in Orthopedic Spine Surgery at the University of Missouri in Columbia, MO.
Dr. Daiber is a fellowship-trained spine surgeon, who is in the first fellowship class to pass the AO Global Spine Diploma Exam part I and part II. She is committed to caring for all her patients as if they were her own family. Dr. Daiber puts a focus on treating her patients with the least invasive surgical procedures, which helps provide the best possible outcome once all other treatment options have failed.
Nicholas A. Amalfetano, DPM, D.ABFAS, FACFAS
Michael Dobrowolski, D.O., MHSA, RD
Dr. Dobrowolski attended The Pennsylvania State University and the Lake Erie College of Osteopathic Medicine, where he completed his Orthopedic Surgery residency. He then completed Fellowship training in Orthopedic Sports Surgery at Medstar, located in Baltimore and Washington D.C. There he served as team physician for the Morgan State Bears.
Dr. Dobrowolski is a fellowship-trained sports surgeon who specializes in knee preservation surgery. He has a focus on cartilage restoration, limb alignment, meniscus repair, as well as ACL reconstruction and repair. He received specialty training in the surgical treatment of shoulder instability, including arthroscopic labral repair, as well as rotator cuff repair and arthroplasty. Hip pain is a special interest for Dr. Dobrowolski. He is one of the few surgeons, regionally, to perform hip arthroscopy to address femoracetabular impingement (FAI) and hip labral tears. Dr. Dobrowolski also treats general orthopedic conditions of the hip and knee. He is certified in MAKO robotic-assisted total hip, total knee, and partial knee replacement surgery.
Dr. Dobrowolski holds candidate memberships with American Academy of Orthopedic Surgeons (AAOS), American Orthopedic Society for Sports Medicine (AOSSM), and American Osteopathic Association of Orthopedics (AOAO).
Nathan Angerett, D.O. | Adult Hip and Knee Reconstruction & Total Joint Replacement
Dr. Nathan Angerett is a fellowship-trained orthopedic surgeon specializing in adult hip and knee reconstruction and total joint replacement, including robotic joint replacement surgery and the direct anterior total hip replacement procedure. Dedicated to helping patients regain mobility and improve their quality of life, he focuses on advanced surgical techniques and personalized patient care.
Dr. Angerett completed his specialty training in Hip and Knee Replacement Surgery through The Baltimore Adult Hip and Knee Reconstruction Fellowship. This esteemed program—a collaboration between LifeBridge Health and The University of Maryland—provided the opportunity to master complex hip revision and knee replacement techniques under the mentorship of some of the nation’s leading joint replacement surgeons.
Before his fellowship, Dr. Angerett completed his Orthopedic Surgery residency at UPMC Harrisburg, where his peers elected him to serve as the Executive Chief Resident. During this time, he spearheaded numerous patient care and quality improvement initiatives. His leadership and dedication earned him the C. McCollister Evarts Resident Leadership Award and induction into the prestigious American Orthopaedic Association’s Emerging Leaders Program.
Dr. Angerett’s academic journey began with pre-medical coursework at the University of Pittsburgh and the University of Pennsylvania. He earned his Doctorate from the Lake Erie College of Osteopathic Medicine, where he was inducted into the National Osteopathic Medicine Honors Society and awarded the Pennsylvania Outstanding Osteopathic Medical Student Award for his exceptional achievements.
A respected researcher, Dr. Angerett has published numerous peer-reviewed articles on a wide range of orthopedic topics. Click here to explore his research publications. His work has been nationally recognized by the American Association of Hip and Knee Surgeons and the American Osteopathic Academy of Orthopedics. Locally, his research has received the Outstanding Research Award multiple times at the UPMC Central PA Annual Medical Education Day. Dr. Angerett serves as a reviewer for the Journal of Arthroplasty and the Journal of Bone and Joint Surgery (JBJS), two of the leading journals in orthopedic surgery.
Dr. Angerett is passionate about providing care tailored to each patient’s needs. He prioritizes non-operative measures whenever possible, offering compassionate and evidence-based treatments designed to restore independence and improve quality of life. For patients requiring surgery, he employs state-of-the-art techniques to achieve the best possible outcomes.
When he’s not caring for patients, Dr. Angerett enjoys spending time with his wife and their three children—two daughters and a son. The family loves cheering on their kids during sports events and relaxing with movie nights. Dr. Angerett’s commitment to family life reflects his understanding of the importance of helping his patients return to what matters most: spending time with the people they love.
Kelsi Tagliati, M.D., D. ABA
Dr. Kelsi Tagliati is a board-certified pain physician and anesthesiologist with special interest in interventional pain management, complementary and integrative medicine and disease prevention.
Dr. Tagliati’s professional experience includes time with Lebanon Veteran Affairs Medical Center and more than 14 years in private practice. During this time she provided comprehensive pain management care for patients with complex pain issues, while working closely with providers from across a range of disciplines, including pain psychology, acupuncture, chiropractic, nutrition and whole health.
She earned her doctorate of medicine from Penn State College of Medicine after obtaining a bachelor’s of science degree in biology from Dickinson College. Following medical school, she completed both her internship and anesthesiology residency at University of Pittsburgh Medical Center. Dr. Tagliati then went on to pursue a fellowship in pain management, also at University of Pittsburgh Medical Center. She has also attended courses in advanced lumbar and cervical procedures and radiofrequency ablation.
Her society memberships include the American Medical Association, American Society of Anesthesiologists, Pennsylvania Medical Society, and Spine Interventional Society (SIS).
A married mother of 12-year-old twin boys, Dr. Tagliati enjoys biking, hiking and outdoor activities.
Physician Assistants / Nurse Practitioners
William J. Polacheck, M.D.
After attending Dartmouth College, Dr. Polacheck received his medical degree from Thomas Jefferson University. He completed an internship at Pennsylvania Hospital before returning to Thomas Jefferson University Hospital for an orthopedic residency. He practiced orthopedic surgery in Central Pennsylvania for fifteen years before joining OIP in 2001.
Dr. Polacheck is certified by the American Board of Orthopedic Surgery and is a member of the Alpha Omega Alpha Honor Medical Society, American Academy of Orthopedic Surgeons and Pennsylvania Orthopedic Society. Dr. Polacheck has also been the Chairman of the Department of Orthopedics at Holy Spirit Hospital since January 2003.
Dr. Polacheck resides in Lemoyne with his wife, Mary Kaye Polacheck, Esq. They have a son, Bill, and a daughter, Lauren.
Daniel P. Hely, M.D.
Daniel Hely, MD is a board-certified orthopedic surgeon who believes the most important part of being a doctor is helping people in pain. He works hard to provide pain relief for his patients and gets satisfaction from making a positive difference in patients’ lives. He recalls, “I was born into a medical family and grew up in a culture that emphasized making the world a better place.” Dr. Hely’s patients have great trust in his medical skills and appreciate the mutually respectful relationships he forms with them. His practice style is relaxed, but he encourages direct interaction and mutual decision making. He believes in presenting all treatment options to patients and working together to find the best solution based on each patient’s goals and lifestyle.
Dr. Hely has expertise in diagnosing orthopedic problems, joint repair and replacement, fractures, sports medicine, minimally invasive surgery and pain management. Dr. Hely is a respected author and lecturer and is a team physician for Dickinson College Athletic Department.
Richard J. Boal, M.D.
After graduating from Temple Medical School, Dr. Boal completed an internship at Presbyterian Medical Center and residency at Temple University Hospital. He joined OIP in 1979 after spending two years as a major in the United States Air Force.
Dr. Boal is a member of the Pennsylvania Orthopedic Society, Dauphin County Medical Society and American Academy of Orthopedic Surgeons. He published “The Percutaneous Lateral Retinacular Release” in Orthopedics in January, 1982.