Loren Duke Fleckenstein

Loren D. Fleckenstein, Sr., M.D., neurosurgeon (retired), decorated U.S. Army veteran, aerobatic aviator and beloved husband and father, passed away peacefully in the company of Connie, his wife of 66 years, at their home in Nacogdoches, Texas, the evening of February 18, 2026. He was 87.

Born in Herndon, Kansas, on March 21, 1938, Dr. Fleckenstein earned the respect of the medical communities where he practiced brain and spinal surgery and the gratitude of patients and their families. Over his 31-year medical career, his diagnostic acumen and his stamina, dexterity and composure during complex, sometimes highly risky surgical cases saved the lives and ensured the quality of life of hundreds of patients.

He graduated from Oberlin High School in 1956. While an undergraduate student at the University of Kansas, Lawrence campus, he and his future wife, Miss Connie Ezell, an undergraduate student in education, first met at the Hawk’s Nest, a student lounge in the Kansas Memorial Union at KU. They were married June 13, 1959, at Linwood Methodist Church in Linwood, Kansas. After graduating with a bachelor’s degree in chemistry, Dr. Fleckenstein entered The University of Kansas School of Medicine, graduating in 1965. The couple had two sons, Loren Duke Fleckenstein, Jr., and David Lee Fleckenstein, born in 1960 and 1963, respectively.

Dr. Fleckenstein went through his residency in neurosurgery at hospitals in Memphis, Tennessee. After completion of residency, he entered obligated active duty with the rank of major in the U.S. Army posted to the 67th Evacuation Hospital in Qui Nhon, South Vietnam. Upon arrival, he was driven directly from the military airport to “67th Evac” to operate immediately on wounded U.S. soldiers.

Maj. Fleckenstein did not confine his wartime service to the operating room. He volunteered on helicopter missions, including combat missions and BNR (body not recovered) missions. During one foray, after treating a wounded M60 machine gun operator as Viet Cong fired on the landed crew, he took over the wounded gunner’s position to join his fellow soldiers in repelling the enemy. On another mission, he was wounded by mortar fire and evacuated for surgery to remove the shrapnel. The U.S. Army awarded him a Purple Heart and a Bronze Star.

Maj. Fleckenstein completed his Army service as a neurosurgeon stateside at Madigan General Hospital, today Madigan Army Medical Center, in the state of Washington.

Following active duty in the Army, Dr. Fleckenstein in 1973 entered private practice in neurosurgery, with privileges at hospitals in Jackson, Tennessee, and Meridian, Mississippi, before he and Mrs. Fleckenstein made their home in 1984 in Nacogdoches, Texas, and his professional home at Nacogdoches Medical Center.

Dr. Fleckenstein was certified by the American Board of Neurological Surgery. He brought to his patients not only a high caliber of medical skill and Hippocratic dedication, he also locally introduced state-of-the-art procedures pioneered at leading medical centers. For example, in Meridian, he was the first surgeon to perform a microscopic transsphenoidal surgery to remove a tumor at the base of the brain. At the time, standard procedure involved a craniotomy, the opening of part of the skull to access the brain. This subjects the patient to considerable physiological stress and morbidity risks. Even in successful outcomes, craniotomy subjects face prolonged hospitalization and recovery. Instead, under a new procedure, Dr. Fleckenstein with the aid of a microscope reached the tumor through the patient’s nasal cavity and sinus. To his satisfaction, the patient was able to be allowed out of bed briefly to walk a few steps the first day after surgery.

Among his diverse intellectual pursuits, two subjects captured his imagination above all: aviation and military history, especially of War World II. As a boy growing up in the wake of that titanic conflict, he would collect military rank and insignia patches from war veterans returning to western Kansas. His personal library would grow to more than 2,000 books on a variety subjects, many of those volumes on World War II.

Dr. Fleckenstein flew his first solo flight from an airstrip in Oberlin, winning his wings at age 16. In his first airplane, a Piper Super Cub co-owned with another pilot, he flew from Memphis International Airport, sometimes surprising local boaters by landing the light, agile airplane with his wife or his sons on sandbars in the middle of the Mississippi River, then going for a stroll before flying back to the airport. An aerobatic pilot, he owned a number of high-performance aircraft. Two of these were a North American T-6 Texan, a World War II-era advanced pilot trainer, and a Beechcraft T-34 Mentor. The latter was repainted per his instructions to match the camouflage and insignia of Focke-Wulf Fw 190 German fighter. The T-34 impressed spectators at air shows where it was flown by Dr. Fleckenstein or his son David, who like his father won his wings as a teenager and today serves as a captain for American Airlines.

Perhaps as a legacy from growing up on the flat, dry plains of western Kansas, Dr. Fleckenstein loved trees and forests. He personally planted oak trees, sycamores and a willow on his properties. He and Mrs. Fleckenstein also loved animals. They rescued injured or orphaned wildlife to repatriate them later into their natural habitat, and they adopted a number of stray cats and dogs.

The couple traveled widely. Among other destinations, they enjoyed cruises in Europe and Alaska and whale-watching in the Sea of Cortés, the gulf surrounded by Baja California and mainland Mexico. They toured Moscow and Leningrad (today St. Petersburg) in the last days of the Soviet Union. Lured by Dr. Fleckenstein’s fascination with Antiquity, they made trips to Rome, western coastal Turkey and Greece, including repeat visits to the island of Delos, an open-air museum of commercial and sacred centers of Greco-Roman civilization. During these trips, one of Dr. Fleckenstein’s most memorable moments was seeing with his own eyes the Antikythera Mechanism, a 2,100-year-old celestial analog computer possibly descended from lost inventions of Archimedes, at the National Historical Museum in Athens.

Dr. Fleckenstein is survived by his wife, Connie; his sons Loren Jr. of Los Angeles, and David of Nacogdoches; daughter-in-law Judy Lee; younger brother Charles M. Fleckenstein and sister-in-law Jo of Merriam, Kansas; and brother-in-law Tom Lee of Coldwater, Mississippi. He was preceded in death by father Loren Lee Fleckenstein, mother Anna Muriel (Morland) Fleckenstein and sister Sheri Fleck-Rieth.

Something the heart must have to cherish

Must love and joy and sorrow learn

Something with passion clasp or perish

And into itself ashes burn

Loren D. Fleckenstein, M.D.

(1971)

Services are under the direction of Cason Monk-Metcalf Funeral Directors.