From basic preceptorship to a top-ranked fellowship, see how Norton Leatherman Spine built one of the nation’s most respected spine programs and welcome its new fellows.

Published: August 21, 2026

Norton Leatherman Spine’s fellowship began in the 1980s, making it one of the oldest in the country — but its modern shape took hold starting in 1990, when Steven D. Glassman, M.D., and John R. Dimar II, M.D., began building on the clinical foundation Kenton D. Leatherman, M.D., had established. What started as a basic preceptorship, common to fellowships of that era, evolved over the following decades into a structured academic program with a dedicated research infrastructure and, increasingly, full integration between orthopedic and neurosurgical spine training. In the 1990s, the fellowship added a dedicated research program and started drawing three to four fellows a year from across the country rather than the occasional visiting surgeon.

By the 2000s, the program’s reputation had grown well beyond the region. As faculty built national and international recognition of their own, the fellowship’s academic output and clinical volume grew in step.

“It sort of snowballed in terms of going from a well-regarded fellowship to being, probably at this point, one of the top programs in the country,” said Dr. Glassman, spine and orthopedic surgeon and medical director of Norton Leatherman Spine.

Training across the spectrum of spine care

While many fellowships concentrate on a single area — degenerative lumbar disease, cervical conditions or scoliosis — Norton Leatherman Spine is among a small number of programs with the case volume to train fellows across the full spectrum of spine care, from pediatric deformity to adult degenerative disease to spinal tumors.

“We’ve tried to make the service to encompass the range of spinal disease, and include perspectives from both orthopedic surgeons and neurosurgeons,” Dr. Glassman said, describing a philosophy that has become one of the program’s defining traits.

That range shows up in how graduates describe their first years in practice.

“They are prepared to be effective spine surgeons day one,” Dr. Glassman said of fellows entering private practice, while those pursuing academic careers leave with both a research background and a professional network that continues to open doors — including for Munish C. Gupta, M.D., MBA, an early Leatherman fellow now serving as vice president of the Scoliosis Research Society.

That network has become a defining feature of recent years. Fellows now practice across the country, and a growing number are reaching the point in their careers where they’re hiring the next generation of Norton Leatherman Spine fellows into their own practices — or preparing to hand those practices off to them entirely.

“There’s a very robust fellowship network that allows Leatherman fellows to work together and to join practices where previous fellows work or have worked,” Dr. Glassman said.

The future of spine care

Looking ahead, according to Dr. Glassman, the program takes a deliberate approach to new technology, adopting techniques only once they’ve proven their value rather than chasing every emerging trend. Spinal endoscopy is one example: Two former Norton Leatherman Spine fellows have become national leaders in the technique, and, according to Dr. Glassman, it may become a more central part of the fellowship curriculum in the coming years.

The bigger priority is succession planning, as the surgeons who built the program’s reputation begin to step back.

“A lot of really well-known fellowships, when the surgeons who started them retired, the group didn’t have a plan to maintain the quality,” Dr. Glassman said.

Norton Leatherman Spine has put significant effort into ensuring that isn’t thestory here — according to Dr. Glassman, the work applies not just to the fellowship, but also to the quality of care the practice provides overall.

He also pointed to a less measurable benefit of running a top program: the fellows themselves.

“Having a top fellowship is a privilege,” he said. “The ability to interact every day and every year with the absolute cream of the crop of young orthopedic surgeons who ask questions and keep you on your toes … is just a tremendous boon to the quality of care provided to our patients.”

The program remains highly competitive, drawing roughly 200 applicants a year for four spots.

Welcoming the newest class of fellows

Five new fellows are joining Norton Leatherman Spine this year, continuing a tradition that now spans more than three decades.

Mahmoud Nofal Attalah Abu-Alkebash

Residencies: Royal Medical Service, Amman; Islamic Hospital, Amman, Jordan
Medical School: Mutah University, Jordan
Undergraduate: Mutah University 

Mitchell F. Bowers, M.D., joins the program in August.

Residency: Vanderbilt University Medical Center, Nashville, Tennessee
Medical School: Meharry Medical College, Nashville, Tennessee
Undergraduate: James Madison University, Harrisonburg, Virginia

Kyle W. Geiger, M.D., joins the program in August.

Residency: University of Iowa Health Care Medical Center, Iowa City
Medical School: Washington State University, Pullman
Undergraduate: Washington State University

Mario Sahlani, M.D.,

Residency:  University of Maryland
Medical School: The University of Toledo College of Medicine and Life Sciences
Undergraduate: The Ohio State University

Brandon C. Yoshida, M.D., joined the program in July.

Residency: University of Southern California, Los Angeles
Medical School: University of Southern California Medical School
Undergraduate: University of California, Los Angeles

Each will spend the year training alongside the same faculty and case volume that has shaped nearly 150 fellows before them — and, in time, will carry that training into practices of their own.