Back pain is one of the common ailments among divers. It usually arises from bad posture and improper lifting practices. In addition, weak muscles and lack of flexibility are major factors contributing to back pain.
Back pain is not uncommon among divers. It can ruin a day of diving, then curtail diving for weeks thereafter, sometimes longer. Depending on the type, it may be a medical disqualification for commercial diving. Although common, almost always easily treated, and more easily prevented, back pain is often mistaken for a mysterious, permanent, unavoidable evolutionary penance for walking on two legs.
Why read this if your back doesn’t hurt? Odds are it probably will one day. Statistically, eight out of ten backs over the age of 18 will, at some time, hurt a little, a lot or an awful lot. Most people with back pain are between 25 and 44 years old. According to some estimates, men suffer back pain two to three times more often than women. One underlying reason is the load of carrying around their larger shoulders, bigger backs and longer, larger torsos relative to their bodies than women. Women usually keep more of their weight lower and biomechanically safer.
Only the common cold beats back pain as the major cause of work absenteeism in the United States. Americans lose an estimated 90 million production days annually. Back injuries are the work industry’s single greatest medical expense, estimated at $100 billion in the United States alone in medical costs, compensation, lost productivity and wages – every year.
An Injury, Not A Condition
Except in degenerative disease, or a sideways curve in the spine called scoliosis, back pain is usually an injury, not a condition. This is an important distinction. After back injury, just as after a sprained ankle or broken arm, you can heal and go back to your life. The key is recognizing that your chronic backache, or the back that “goes out” once in a while, is an injury. This usually develops slowly over time from classic back abuse you do every day without knowing it. You can usually identify and reduce or eliminate the problems.
Common Origins Of Back Pain
This section does not deal with special cases of back pain from arthritis, osteoporosis, or scoliosis. However, the bad habits described here increase anyone’s risk of pain and injury.
MUSCLE: Most back pain is muscle related. Ordinary, daily habits such as chronic bad sitting, standing and bending posture, eventually stretch, strain and contract muscles into painful knots. Bad posture allows your back to slump into positions that put relentless pressure on discs, nerves and other muscles. Sometimes muscles on one side of a joint are stronger than the balancing muscle set on the other side. The weaker side can’t counter the pull of stronger opposing muscles, furthering bad posture stress. Such muscle inequality can occur even in people who work out regularly.
Poor flexibility of back and leg muscles is a common culprit in back pain for several reasons. Tight muscles strain instead of stretch during activity and pull your back into bad postures. The range of motion required to strain tight, low back muscles is small, accounting for many painful backs after a day of diving. Hip flexors are the muscles that bend your leg forward at the hip. Tight hip flexors, common in people who sit a lot, sometimes pull the pelvis forward. The shift in the normal tilt contributes to low back pain. Hamstrings are the triple set of muscles in the back of your thigh. They work to both bend your knee and also swing your leg behind you. Tight hamstrings are thought to influence the tilt of the pelvis to the back, contributing to back pain. Add slinging tanks and gear around in ways your back isn’t designed to abide and back pain eventually afflicts the majority of divers.
OTHER INJURIES: Some back pain comes from other injuries. A knee or ankle injury may throw off how you walk and stand. Neck problems can cause pain in your upper back. An often overlooked source of back pain is the foot. When your big toe joint works as it should, it bends pliably and your leg and body pivot around it to walk normally. Sometimes, however, although it may not hurt or be obvious, it does not work properly during the push off phase of walking, throwing off foot position, gait and posture of your head and trunk. Your lower back muscles and discs bear the brunt.
DISC: A small percentage of back pain comes from disc problems. Discs are flat fibrocartilage cushions between bones. You have tiny little discs between your jawbone and your head bone. Sometimes they wear out, causing pain at the jaw joint called the temporomandibular joint or TMJ. You have two larger discs called meniscus in each knee. Injuring your meniscus causes knee pain that will be covered in another article on divers’ knees. Your most long suffering discs sit between each of your 7 neck bones called cervical vertebrae, 12 upper back bones called thoracic vertebrae, 5 lower back bones called lumbar vertebrae, and between the lumbar vertebrae and the end of your spine, called your sacrum. These bones, and their position relative to other vertebrae, are often referred to by initials. The seven cervical vertebrae are C1 to C7. If you tip your head forward and feel the back of your neck, the most prominent bump is your C7 vertebra. Your other six cervical vertebrae are above it. Below C7 begin the 12 thoracic vertebrae, T1 to T12. Each thoracic vertebra attaches a pair of ribs, 12 pairs in all. (Both men and women have 12 paired ribs, 24 total. Men do not have one less rib!) Your five lumbar, or low back, vertebrae are L1 to L5. The discs most often involved in low back pain are between L4 and L5 and, particularly between L5 and S1, the first sacral vertebra. Disc protrusions called herniations usually result from chronic outward pressure on discs from allowing your back to curl forward into a C when sitting or bending. This curled posture pushes discs out, out, out, over time. The edges begin to fray like a wearing tire. One day, after even a small provocation, the disc finally protrudes far enough for a sudden onset of disc pain. Then, the person attributes the injury of the slipped disc to the one event that brought on the pain, never realizing it was brewing all along. A long, tough ligament that runs down your vertebrae resists the backward movement of discs. Because of it, a disk usually pushes out sideways. The long nerves serving your legs exit the vertebrae to the side. When a disc bulges against these nerves, pain extends down the leg and in severe cases, reduces function. In the most serious cases, discs protrude directly back into the spine, disrupting motor ability and sometimes bowel and bladder function.
Although herniated discs used to be thought of as a life sentence, we now know it’s usually not so. Most disc protrusions heal if you let them and you can go back to your life as after any other injury. Best of all, back pain, whether from muscle or disc, is usually avoidable.
How You Get Back Pain
There are two main ways to screw up your back: the quick way and the slow way.
THE QUICK WAY TO SCREW UP YOUR BACK: The most classic onset of back pain is after you lean over, twist to the side and lift something. Why is this?
If you do nothing more than stand still and bend over with straight legs, you put hundreds of pounds of force on each vertebral disc, with the most on L5 through S1. Twisting when you lean is worse. Yanking a weight is often the death blow. There are many opportunities for divers to do exactly those three things: at airport baggage carousels, airfill stations, slinging tanks into boat racks and back onto shore and leaning over to yank gear out of trunks. Lifting properly is no problem. Lots of people lift weights for hobbies or their living. Many people even lift dangerously for years without outward signs of injury – until one day.
THE SLOW WAY TO SCREW UP YOUR BACK: Years of wear and tear add up. Chronic slouching can injure your back over several years as badly as a single accident. Your body weight alone is enough to injure both muscles and discs through bad sitting, standing and bending habits.
The small of your back is supposed to curve inward to a certain extent. One of several ways to hurt your back slowly, particularly your lower back, involves reversing the curve with a bad posture involving lumbar flexion. Flexion is when you bend a joint. Bending your elbow, for example, is elbow flexion. Putting your chin on your chest is neck flexion. Hip flexion occurs when you bend forward at the hip or raise your leg. Genuflection (genu is the Latin word for knee), is when you bend your knee in church, but just plain knee flexion any other time. Sitting, standing and lifting with a round back instead of maintaining the normal inward curve of your lower back is lumbar flexion. Too much lumbar flexion squeezes discs outward. The disc may eventually break down or blow like an abused tire.
Continuous back flexion also overstretches the long ligament down the back of the spine, weakening the back and allowing discs more room to protrude. On top of that, chronically holding your back muscles, or any muscles for that matter, in a stretched position weakens them. Habitually standing with your head forward also overstretches the back of your neck with similar results. A forward head, not only a problem to your neck, contributes to upper back pain, usually between the shoulders, but may radiate to other areas.
One of several ways to hurt your back slowly is sitting and bending so the normal inward curve of your lower back curves outward. This bent forward posture is called lumbar flexion. Too much lumbar flexion eventually squeezes discs outward and overstretches the long ligament down the back of the spine, weakening your back and allowing discs more room to protrude. The chronic stretch of lumbar flexion weakens back muscles.
The second main bad posture is from weak abdominal muscles that allow you to sag backward, exaggerating the normal inward curve. This does not cancel problems from excess flexion but creates back pain of its own. Often, people who sit and bend with too much flexion also stand with excess arching.
In an average day, most people repeatedly abuse their backs unknowingly. In this way they are brewing a back injury that may not become apparent for years. Ironically, once their backs finally succumb to pain, they give up active exercise that helps and continue sitting and lifting with a rounded back and standing with too much arch – all major back injury producing events. A particularly ironic sight is back pain patients sitting in lumbar flexion in doctors’ offices and physical therapy waiting rooms – worsening their condition while they sit. Here’s a sample of daily back abuse:
You wake up and sit curled in flexion at the edge of the bed. You slouch over to the sink and bend over to splash water on your face. Bend over and twist to make the bed. Sit curled forward in lumbar flexion in a breakfast chair, then again in the car or public transit to work. Commuting healthy by bicycle? Back flexion there, too. Worse with racing handlebars if you curl over them in poor form. Sit in flexion at work, including lunch. Bend sideways from your chair to yank open file cabinets. Stand and walk with excess arching, often carrying packages compounding the strain. Commute home in flexion. Then, maybe to the gym? Several, still popular exercises do more to weaken your back than strengthen it: weight lifting while leaning over from the waist, straight leg dead lifting, forced repetitive back bending such as toe touches from a standing position, swinging elbows down to opposite knees and forced, repetitive back arching such as donkey kicks that swing the leg overhead from a hands and knees position. Well-meaning people often start their exercise routines with a back abuse doozie – they bend over straight legged to touch toes, worse without warm-up. Although it often feels good on tight muscles, it’s tough on your back in the long run. Moreover, stretching is not a warm-up and should not be done until you warm yourself with muscular activity such as jogging or bicycling. Trained exercise instructors know not to do these exercises, however, they are still remarkably widespread in gyms and schools across the country. Rowing machines are great exercise but cause heavy duty flexion if done incorrectly. Still doing sit-ups not crunches? Still doing leg raises? Those two do little for your abdominal muscles and are tough on your lower back bones where the muscles you really use for situps and leg lifts connect. (See the July 1993 column on abdominal muscles for a detailed explanation of why sit-ups and leg lifts benefit other muscles more than your abs.)
When you get dressed, you may bend wrong to pull on shoes and socks. Put a thick wallet in your back pocket that makes you sit crooked. Bend over and twist to pick up your gym bag and sling it over one shoulder. The researchers concluded that such unequal forces might contribute to the high percentage of school children turning up with scoliosis. They suggested switching to knapsacks to distribute the load. In adults, shoulder bags seem to contribute to muscular pain.
There is back flexion on your commute home, at dinner, in front of the sink and in a rounded chair or couch in front of the TV. Have young kids? Bend over wrong to pick them up. Hold them while standing arched. Flexion to tuck them in. Add chronic, incorrect lifting during house and yard work, especially tanks and gear in and out of trunks, boat lockers and baggage racks. Pitching boat decks add much potential to strain tight muscles, especially while wearing full gear. This overview is just a scratch in the surface of what’s behind back pain but you get the idea. Major factors in back pain are weak muscles and lack of flexibility. Poor sitting, standing and bending habits are major behavioral contributors. The effects are often cumulative, such as in smoking. One day you bend over to pick up a sock and your back bids you hasta lumbago.