AHN Spine Surgery Fellowship Faculty

Orthopaedic Spine Surgery

Dr. Sauber is the founding director of the AHN Spine Surgery Fellowship and Division Director of Orthopaedic Spine Surgery at Allegheny Health Network. He also serves as Chief Quality Officer of the Department of Orthopaedics, Clerkship Director for Orthopaedic Surgery, and Chair of the Perioperative Executive Committee at AHN Wexford Hospital.

He completed his orthopaedic surgery residency at Allegheny Health Network — where he served as Chief Resident — and his spine fellowship at William Beaumont Hospital in Royal Oak, Michigan. He is board certified by the American Board of Orthopaedic Surgery and is an Assistant Professor of Orthopaedic Surgery at Drexel University College of Medicine. Dr. Sauber has been named a Castle Connolly Top Doctor (2025) and received the Golden Mallet Award as AHN’s top orthopaedic educator (2023).He serves as an endoscopic spine surgery educator and course faculty for Arthrex, teaching uniportal endoscopic technique to surgeons nationally.

• Clinical interests: Adult cervical, thoracic, and lumbar reconstructive and degenerative spine surgery; minimally invasive and endoscopic techniques; robotic-assisted spine surgery; spinal trauma; cervical and lumbar disc arthroplasty; and perioperative quality, safety, and outcomes.
• Academic appointments: Assistant Professor of Orthopaedic Surgery, Drexel University College of Medicine; Clinical Instructor, Lake Erie College of Osteopathic Medicine (LECOM).
• Board certification: American Board of Orthopaedic Surgery.
• Selected publication:  Lead author, “Lumbar Endoscopic Spine Surgery: Where Are We?” in Essentials of Endoscopic Spine Surgery (Singh, Park, and Kim, eds.; Academic Press / Elsevier, 2025).
• Memberships: American Orthopaedic Association (Active Member), North American Spine Society, AO Spine, Lumbar Spine Research Society, AO Trauma, AAOS.

Orthopaedic Spine & Trauma Surgery

Dr. Altman is a nationally recognized expert in orthopaedic spine and trauma surgery. His spine practice spans cervical and lumbar disc surgery, spinal stenosis, spinal trauma, metastatic tumors of the spine, and minimally invasive spine surgery, complemented by extensive expertise in complex extremity and pelvic fractures.

He completed dual fellowship training — a spine surgery fellowship at the University of Pittsburgh Medical Center and an orthopaedic traumatology fellowship at Harvard Medical School — following an orthopaedic surgery residency at Hamot Medical Center and an AO North traveling fellowship at Harborview Medical Center in Seattle. He earned his medical degree from Temple University School of Medicine.

Dr. Altman is Director of Orthopaedic Spine Trauma at Allegheny General Hospital, Program Director of the Orthopaedic Surgery Residency at Allegheny Health Network, and a Professor of Orthopaedic Surgery at Drexel University College of Medicine. He is a Past President of the Allegheny General Hospital Medical Staff.

An active researcher, he has published more than 60 articles in leading journals, including The Spine Journal and The Journal of Bone and Joint Surgery, along with multiple book chapters. His current research focuses on bone-implant healing and improving outcomes after spinal and major orthopaedic injury.

• Clinical interests: Cervical and lumbar disc surgery, spinal stenosis, spinal trauma, metastatic tumors of the spine, minimally invasive spine surgery, and complex pelvic and extremity fractures.
• Education and training: MD, Temple University School of Medicine; orthopaedic surgery residency, Hamot Medical Center; spine surgery fellowship, University of Pittsburgh Medical Center; orthopaedic traumatology fellowship, Harvard Medical School.
• Board certification: American Board of Orthopaedic Surgery; Fellow, American College of Surgeons (FACS).
• Memberships: American Academy of Orthopaedic Surgeons, North American Spine Society, Cervical Spine Research Society, AO Spine, Orthopaedic Trauma Association.

Dr. Holmberg is an orthopaedic spine surgeon at Allegheny Health Network. He completed his orthopaedic surgery residency at AHN and his spine fellowship at West Virginia University in Morgantown, West Virginia. He earned his Doctor of Osteopathic Medicine from Lake Erie College of Osteopathic Medicine and holds a Master of Science in Medical Science from the UNTHSC Graduate School of Biomedical Sciences.

He is a recipient of the AO Spine Fellows North America Global Spine Diploma and the AO Global Spine Diploma Program Excellence in Learning Award (2025). He has contributed book chapters on sacral trauma and lumbopelvic dissociation to the Rothman-Simeone textbook and on robotic spine technology to the Handbook of Spine Technology.

• Clinical interests: Robotic-assisted spine surgery, minimally invasive techniques, spinal trauma, lumbar disc herniation in athletes, and bone-graft biology.
• Memberships: AO Spine, NASS, American Osteopathic Association of Orthopaedics.

Neurosurgical Spine Surgery

Dr. Yu is a neurosurgical spine surgeon and System Vice Chair of the Department of Neurosurgery at Allegheny Health Network. He serves as Director of Surgical Neuro-Oncology, Skull Base Surgery, Cerebrovascular Neurosurgery, and Minimally Invasive Spine, and as Assistant Director of Adult Deformity Surgery — bringing the fellowship deep expertise in minimally invasive spine surgery, adult spinal deformity, and spinal oncology, including en-bloc tumor resection.

He completed his neurosurgery residency at Allegheny Health Network following a general surgery internship at AHN, and earned his medical degree from Saint Louis University School of Medicine. He also holds master’s degrees in biomedical engineering and in computer information systems from the University of Miami. He is board certified by the American Board of Neurological Surgery and is a Fellow of the American Association of Neurological Surgeons (FAANS) and the Congress of Neurological Surgeons (FCNS).

Dr. Yu is an Associate Professor of Neurosurgery at Drexel University College of Medicine and directs AHN’s ABNS CAST–accredited complex spine and neuro-oncology fellowship programs. Since 2015 he has served as an unaffiliated neurotrauma consultant for the National Football League. He has been recognized as a Castle Connolly Top Doctor (2022–2026) and has received Drexel’s Golden Apple Award for excellence in medical student education.

• Clinical interests: Minimally invasive spine surgery, adult spinal deformity, spinal oncology and en-bloc tumor resection, complex spine, skull base, and cerebrovascular neurosurgery.
• Education and training: MD, Saint Louis University School of Medicine; general surgery internship and neurosurgery residency, Allegheny Health Network; MS, biomedical engineering and MS, computer information systems, University of Miami.
• Board certification: American Board of Neurological Surgery; FAANS; FCNS.
•  Memberships: American Association of Neurological Surgeons (AANS), Congress of Neurological Surgeons (CNS).

Joining faculty October 2026

Dr. Kuczmarski joins the AHN spine faculty in October 2026 following completion of his orthopaedic spine surgery fellowship at Rush University Medical Center / Midwest Orthopaedics at Rush in Chicago. He completed his orthopaedic surgery residency at the University of Miami / Jackson Health System and earned his medical degree from the Warren Alpert Medical School of Brown University. He holds a Master of Science in Biology (highest honors) from Villanova University.

He brings a strong publication record in spine and orthopaedic outcomes research, with peer-reviewed work in cervical and lumbar disease, deformity, and arthroplasty outcomes.

• Clinical interests: Minimally invasive lumbar decompression, indirect decompression for central stenosis, cervical spine surgery, spinal oncology, and outcomes research.
• Honors: ABOS Part I 95th percentile, Phi Beta Kappa, Phi Kappa Phi, Connelly-Delouvrier International Scholar, NIH T35 awardee.

Dr. Cheng leads the dedicated spine research team that anchors the fellowship’s academic mission. A mechanical engineer by training, he earned his PhD in mechanical engineering from the University of Wisconsin–Madison and is a Professor of Neurosurgery at Drexel University College of Medicine and an Adjunct Professor of Bioengineering at Carnegie Mellon University.

He directs AHN’s spine and biomechanics research laboratory, is editor of the Handbook of Spine Technology (Springer), and holds multiple U.S. patents in spinal and tissue-engineering technology. His honors include the NASS Nordby-Smith Award for Minimally Invasive Surgery and the ISASS Best Basic Science Paper Award. He works directly with the fellow to scope, execute, and publish the two publishable-quality research projects required during the fellowship year.

• Research interests: Spinal biomechanics, motion preservation and disc arthroplasty, interbody and implant device development, robotic-assisted instrumentation, and bone-graft and tissue-engineering technologies.
• Selected work: Editor, Handbook of Spine Technology (Springer); multiple U.S. patents; extensive peer-reviewed publication record with the AHN spine faculty.
• Memberships: Orthopaedic Research Society, North American Spine Society, AO Spine, Lumbar Spine Research Society, American Society of Mechanical Engineers; Director, International Chinese Spine Society.