Youth have no idea what a vinyl record is, so “sounding like a broken record” means nothing to them. Spinning those discs with friends—happy memories, but broken discs? Mine came coaching kids’ soccer. In my mind the maneuver worked perfectly: Drag back, turn, and the ball would be on my left foot. Reality differed: an unpleasant sound from behind and blinding pain shooting down my leg. I had just joined 80 percent of folk suffering back pain—in my case, acute disc prolapse. Back pain takes many forms with numerous causes. For this column it’s broken discs.
Everyone knows what a disc brake is, but the term “slipped disc” may cause many to have inaccurate notions of what the discs in our back look like. The spine consists of bones, nerves, discs, muscles, and ligaments. The 33 vertebral bones include seven cervical (neck), 12 thoracic (chest), five lumbar (low back), five fused sacral (pelvis), and four fused in the coccyx or “tailbone.” The spine should be in a straight line north-south with two forward curves (lordoses) and two backward curves (kyphoses). Central vertebral holes accommodate the spinal cord; little windows (foramina) allow nerves to pass to arms, legs, and so on. Strong muscles surround the spine, and fibrous ligaments hold bones together. Between vertebrae (other than the skull and the first vertebra) sits a disc allowing movement, providing shock absorption, and preventing bone-on-bone friction. The disc has a tough outer shell (anulus fibrosus) and jelly-like interior (nucleus pulposus). Think jelly donut, only less tasty. Pressure on one area of the anulus squishes the interior nucleus, distributing stress. Discs are named by the vertebrae they separate, so that between last lumbar and first sacral vertebrae is L5/S1—one of those most commonly injured.
Sudden movement or uneven force (as in my Bend It Like Beckham move) can tear muscle fibers or ligaments, or cause an anular bulge or rip and nucleus jelly to escape. A munched-on donut can ruin your shirt with dribbling jam. A breached disc can also ruin your day, its jelly pressing on nerves in canal or foramina. It is not just physical pressure of nucleus on nerve, but also chemical irritation. Understanding this mechanism enables comprehension of symptoms experienced.
Other than sudden intense pain, one might suffer limitation of movement and inability to stand straight; a few whiskeys can have the same effect. Additionally—especially if the nerves are affected by disc damage—constant, “referred” nagging pain might be felt elsewhere, such as the hip and knee when L5/S1 is the culprit— sciatica means pain experienced from sciatic nerve irritation. Disc rupture affecting nerves can produce muscle weakness; low back discs can cause problems with gait, bladder, and bowel function—warning signs.
Back problems usually resolve with rest, heat, muscle relaxants, and anti-inflammatory drugs (ibuprofen). Some swear by acupuncture, yoga, and a firm mattress. If you experience no improvement, worsening symptoms, or referred pain, see your doctor. Examination may reveal impact on natural spinal curvature—pronounced bulging backward or forward and tilting away from the affected side because of muscular spasm. Unending pain lasting more than a few weeks, inability to raise one leg beyond a certain angle, or signs suggesting nerve impingement may inspire your physician to order an MRI, which shows bony and soft tissues. In longstanding cases an electromyogram is used to detect nerve-muscle impulses. With failure of the above therapy, a steroid injection may prove beneficial. This may not help you win the Tour de France, but may get you through your day without pain.
Chronic sufferers may be helped by TENS—transcutaneous electrical nerve stimulation, or tiny electric shocks that interfere with pain pathways. Sometimes surgery becomes necessary, certainly with obvious nerve damage and functional loss. Procedures involve removing impinging disc material (discectomy), enlargement of space for nerves to exit the canal (laminectomy), and, occasionally, fusing vertebrae together. Operations are performed via conventional back incisions or under microscopic guidance (microdiscectomy) purportedly limiting surgical trauma, although recovery times are similar. Techniques to destroy errant disc material or treat nerves with injected chemicals or energy sources via needles remain of uncertain value. After removing a diseased disc surgeons may fuse vertebrae to prevent instability and vertebrae rubbing together. Artificial discs have been introduced but have yet to become commonplace.
One is at higher risk of back problems if overweight. Think about it: Exceed the maximum gross aircraft weight and problems may ensue—and the same goes for your back. Inactivity and poor technique when lifting heavy weights also put one at risk. Regular exercise, especially core-strengthening exercises such as Pilates, helps prevent problems.
As nasty as disc problems can be, back pain can be a warning sign of other, more serious diseases such as osteoporosis, various cancers, and abdominal aortic aneurysm.
So enjoy old records and avoid broken discs. Take care lifting the tool box or clambering under the wing, watch your weight, and keep your nucleus inside its anulus!
E-mail the author at [email protected]. Jonathan Sackier is a surgeon and private pilot living in Virginia.