The wounds of war can go far beyond what meets the eye. From mental health issues to pain and illness that persist long after they've left the battlefield, veterans face a multitude of health troubles either unique to their service or more frequent among them than the general population.

"Folks returning from combat have a constellation of health concerns, including physical issues, psychological issues and psychosocial issues concerning things like work and family," said Dr. Stephen Hunt, national director of the U.S. Department of Veterans Affairs Post Deployment Integrative Care Initiative.

"This is a population that has unique health care needs that need to be addressed," added Hunt, who is based in Seattle. "It's something that really needs to be done by a team. We can't do it without the collaboration of other providers, and the knowledge and presence of the community."

Some of the most common physical complaints of returning soldiers cannot be classified into a single disorder, Hunt said. They include nonspecific symptoms such as fatigue, pain and cognitive disturbances such as memory and concentration problems.

"The interesting thing is, we see this after all wars," he said. "We think it's a reflection of the duress and intensity of the situation. They're worn out, hurting and it's kind of hard to think straight."

Here are seven health conditions confronting veterans:

Musculoskeletal injuries and pain

Just over half of all veterans' post-deployment health visits address lingering pain in their backs, necks, knees or shoulders, Hunt said. And according to an August study in the Journal of Pain, about 100,000 veterans of the Gulf War nearly 20 years ago have reported chronic muscle pain. Previous research indicated that regular, sustained exercise can help reduce that pain, which doctors encourage to help avoid disability.

Mental health issues

While post-traumatic stress disorder (PTSD) among soldiers has been well publicized, other mental woes can also result from the trauma of war. A June study in the journal Archives of General Psychiatry found that one in 10 Iraq war vets develop serious mental problems, including violent behavior, depression and alcohol abuse. The study found that PTSD or depression seriously impaired daily functioning in 8.5 percent to 14 percent of these vets.

Disabling on its own, PTSD is also linked to the development of physical illnesses for veterans as years pass. Researchers from Walter Reed Army Medical Center in Washington, D.C., reported this year that 54 percent of veterans with PTSD also had sleep apnea, compared with 20 percent of PTSD patients in the general population. PTSD in vets is also associated with a greater risk of developing dementia, according to a June study in Archives of General Psychiatry.

Chemical exposure

Research by the American Heart Association found that exposure to nerve agents such as sarin — which can trigger convulsions and death on the battlefield— may cause long-term heart damage in Gulf War veterans. The damage can include an enlarged left ventricle, heart rhythm abnormalities or a reduction in the pumping strength of the heart.

"Environmental agents and toxic chemicals are very common in combat theaters," Hunt said, "and we need to watch [these vets] closely."

Infectious diseases

As a rule, all military personnel are given routine vaccinations before deployment. Yet veterans suffer disproportionately from certain infections that civilians almost never experience for which vaccines are not available, according to the U.S. Department of Veterans Affairs. They include bacterial infections such as brucellosis, which may persist for years; campylobacter jejuni, which causes abdominal pain, fever and diarrhea; and Coxiella burnetii, which in chronic cases can inflame the heart.

Leishmaniasis, a parasitic disease caused by the bite of a sand fly native to the Middle East, is a particularly brutal condition veterans experience. Those infected suffer weight loss, fevers, headaches, muscle pain and weakness, anemia, and enlargement of the spleen and liver. It can be fatal if untreated, according to the VA.

Noise and vibration exposure

Hearing loss and impairment — including persistent ringing and buzzing in the ears — are common effects of harmful noise from gunfire, heavy weapons, noisy engine rooms and aircraft, Hunt said. Additionally, vets who regularly worked with machinery can suffer vibration exposure, which can prompt irreversible lower back pain or numbness and pain in the hands and fingers, according to the VA.

Traumatic Brain Injury (TBI)

TBI, often brought on by a blow or jolt to the head, disrupts brain function and has been called the signature wound of the fighting in Iraq and Afghanistan, according to the National Academy of Sciences. Blast exposures and other combat-related activities put service members at greater risk for sustaining a TBI compared to their civilian counterparts, according to the Defense and Veterans Brain Injury Center.

Common effects of TBIs include cognitive issues such as shorter attention span, language disabilities, and an inability to process information. Vets can also suffer from lack of motivation, irritability, anxiety and depression, headaches, memory loss and PTSD.

"Between 70 and 80 percent of combat deaths are from blast-related exposure," Hunt said, "and of survivors, 20 percent report that they may have had an event that resulted in a mild concussion. Whether there will be any long-term effects is difficult to ascertain."

Urologic injuries

Penetrating injuries to the groin area during battle are often treated only after life-threatening injuries have been dealt with, said Dr. Arthur Smith, a Medical College of Georgia urologist who spoke at the Warrior Health Symposium last month. Injuries to the bladder, ureters, kidneys and genitalia usually require complex surgery, Smith said, but complications often arise because treatment must be put off.

This article was provided by MyHealthNewsDaily, a sister site to LiveScience.