Too soon after you and your partner sit down to watch the game, the tones sound that send you to care for a 55-year-old male with lower back pain. When you arrive on scene, you see Mac lying supine on the floor with his legs bent up. He’s in obvious discomfort, moaning and rocking back and forth.
His skin is warm, pink, a little diphoretic and he responds appropriately to your questions. He tells you while attempting to have a bowel movement he developed an acute onset of pain in his lower back. Mac says he has a history of “throwing his back out” but says this feels different. He has some leftover Flexeril (cyclobenzaprine) from the last time he hurt his back, which he took about an hour ago without decrease in his discomfort.
He has a strong, slow radial pulse. He identifies no respiratory distress and lung sounds are clear in all fields. His initial blood pressure is 198/140 and is equal in both arms. His only history is that of hypertension, which he controls with metoprolol (a beta-blocker), and hyperlipidemia, which he treats with lovastatin.
Mac, obviously upset by his condition, aggressively tells you he needs to receive diazepam. It’s the only thing that has helped his back pain in the past. You explain to him that as a BLS crew you can’t provide medications, but you’ll transport him to the emergency department where the staff will be able to appropriately manage his condition. Lifting Mac onto your stretcher, you help him get as comfortable as he can. There’s no change in his condition during transport.
This case presents interesting possibilities. Lower back pain is not an uncommon complaint—most adults will experience some form of lower back pain during their life. According to the Center for Disease Control’s 2012 report on health in the United States with special feature on emergency care, in 2011 an average of 30% of adult Americans over the age of 18 had experienced lower back pain in the three months prior to being surveyed.
The lower back is a series of lumbar vertebra supported only by the muscles of the back and abdomen. Common causes of lower back pain involve musculoskeletal sprains and strains. Improper lifting can easily cause damage to these muscles.
Damage can also occur to the spine. Between each of the vertebra there’s an intervertebral disk that can herniate or bulge, causing pain. These injuries can be treated with pain medications such as codeine and benzodiazepines such as diazepam (Valium), which is what Mac requested.
Long-term care includes physical therapy and, in some cases, surgery. Many of these patients struggle with chronic lower back pain and some patients develop addictions to the medications used to treat their conditions.
Damage to the nervous system must also be considered. The spinal cord travels from the base of the brain to the level of L2, at which point the spinal cord becomes the cauda equina (horse’s tail). Multiple nerve fibers leave the spinal column, innervating the distal extremities. These nerves can become inflamed or pinched, commonly resulting in shooting leg pain associated with movement or position. Sciatica—the impingement of the sciatic nerve resulting in pain radiating from the lower back, into the buttocks and down one or both legs—is an example of this condition.
In nerve impingement, the patient may experience numbing or tingling (parethesia) in the distal extremity. Distal pulses will be present and equal with good circulation to the lower extremities.
A more serious condition causing lower back pain is cauda equina syndrome. With this condition there’s a proximal impingement of the cauda equina. Patients can experience lower back pain, numbing and tingling down both legs, and incontinence. Cauda equina syndrome commonly needs surgery to avoid permanent paralysis.
More Serious Causes
There are other causes of lower back pain that are potentially more concerning and may be life-threatening. These must be carefully considered by EMS providers as well.
An abdominal aneurysm is a weakening and ballooning of the wall of the descending aorta. The aneurysm commonly develops just above the bifurcation into the common iliac arteries. The aneurysm can put pressure on the intestines, giving the patient the sensation they need to move their bowels. Bearing down may have devastating consequences in these patients, causing the aneurism to grow or to rupture, which may result in life-threatening hemorrhage.
These patients may present with decreased or absent pulses on one or both of their lower extremities. These patients should be considered emergent by EMS and be transported rapidly to a facility with surgical capabilities. Watch for signs of shock.
Upon arrival at the ED, Mac was actually determined to have an abdominal aneurysm. His physical exam in the ED revealed decreased distal pulsed in his feet and weak femoral pulses, and a CT scan revealed the aneurysm on the descending aorta. He was taken to surgery where the aneurysm was repaired, and he was discharged soon after.
EMS should consider a back pain complaint as a potentially serious condition. Many cases of back pain are chronic and require pain management and referral for definitive care. Other causes may be immediately life-threatening. EMS should consider both extremes and be thorough in their assessment and aggressive with treatment and transport as indicated by physical findings.