JOINT BASE SAN ANTONIO – FORT SAM HOUSTON, Tex. — Army Sgt. Bowe Bergdahl will require a lifetime of medical care as a result of the injuries he sustained during five years of captivity after he walked away from his base in Afghanistan in 2009 and was captured by insurgents, a medical professional said Friday.

Curtis Aberle, a family nurse practitioner and case manager for Bergdahl at the Brooke Army Medical Center in San Antonio, said the soldier suffered muscular nerve damage in his lower legs, degenerative back damage and a loss of range in motion in his left shoulder that prevents him from lifting heavy objects. He testified in a preliminary hearing for Bergdahl, who faces charges of desertion and misbehavior before the enemy.

Bergdahl, 29, faces up to life in prison if convicted. He was held in a crouched position for long periods of time while imprisoned, and would be unable to deploy again, Aberle said.

The detail is important in Bergdahl’s case because he could be denied medical benefits if convicted. Aberle said that when Bergdahl attempted a modified version of the Army’s physical fitness test in the last few months, walking 2.5 miles caused his legs to swell “to the point where he could not wear any boots.” The condition is likely permanent, he said.

“It’s my opinion that Sergeant Bergdahl does not meet retention standards for the Army, and should not remain in the military,” Aberle said.

Aberle testified on the second day of what is known in the military as an Article 32 hearing. The officer overseeing the hearing, Lt. Col. Mark Visker, will make a recommendation about whether Bergdahl should be court-martialed to Gen. Robert B. Abrams, who is in charge of the case.

The defense is expected to continue calling witnesses Friday, including Maj. Gen. Kenneth R. Dahl, who questioned Bergdahl extensively after he was recovered by a U.S. Special Operations team in Afghanistan in May 2014 as part of a controversial swap for five Taliban officials who were released from detention at Guantanamo Bay, Cuba. They are now in Qatar.

The first witness called by the defense was Gregory Leatherman, a former sergeant and infantryman in Bergdahl’s platoon. He testified that he raised concerns during their 2009 deployment to more senior soldiers about Bergdahl’s struggle to adjust to the deployment, but was told to keep quiet.

“It was not something I was incredibly alarmed about, but it was something that I needed to be addressed,” Leatherman said of Bergdahl’s struggles.

Prosecutors called three witnesses against Bergdahl on Thursday to describe the chaos his June 30, 2009, disappearance from a small base in Paktika province caused. His former platoon commander, company commander and battalion commander described soldiers worked to the point of exhaustion in the following weeks, as they searched for him across several provinces.

The former platoon commander, Capt. John Billing, said Thursday that Bergdahl left his rifle and other possessions on his cot before he left. He had never caused problems before walking away, he told a prosecutor, Maj. Margaret Kurz.

“I was in shock, m’am,” Billings said of the disappearance. “I was in absolute disbelief that I couldn’t find one of my men. It’s a hard thing to swallow.”