Preventing low back pain and injuries
Knowing how to minimize the risk of back injuries is important for everyone, given that low back pain is the most common injury afflicting humankind! The good news is that, by understanding how certain factors place the low back at risk of injury, and practicing some preventative lifestyle habits, we can minimize our chances of painful, costly and sometimes disabling injuries.
Here is a summary of the primary risk factors for low back pain and injury, and their correlating prevention measures:
(1) Bending, twisting, or over-stretching the spine. Prevention: keep spinal movement and position within its natural limits.
(2) Excess body weight. Prevention: lose excess body weight, maintain safe weight.
(3) Prolonged sitting (including driving). Prevention: take frequent short breaks from necessary sitting; minimize unecessary sitting; stand, walk and move around whenever possible.
(4) Poor tissue health from food choices, smoking, inactivity, and psycho-social stress.
Let’s look at the risk factors, and prevention measures, for low back pain and injury one at a time in more depth.
Bending forward, backward, or to the side, as well as rotation or twisting motions, all stretch and strain the ligaments that connect the vertebrae and disks to each other. Stretching is good, right? Yes and no.
Muscles and tendons are built to contract and relax, and stretching muscles and tendons can both strengthen and lengthen them–if done slowly and carefully to a warmed-up muscle. But muscles and tendons can be overstretched, which can result in painful micro- or macro-tears (“strains”).
Ligaments, which are like short, thick, stiff rubber bands connecting bone to bone to form joints, are even more vulnerable to tearing (“sprains”). Ligamentous tissue is not able to stretch more than 10% of its resting length without permanently elongation (deformity or laxity). And unlike muscles, which have rich blood supply and can heal well and completely in 4-8 weeks, ligaments have poor blood supply. Ligament healing is measured in months to years and can be incomplete. The abrupt tissue failure than can occur when ligaments are stretched past their resting length can result in difficult-to-treat and even irreversible weakening and joint de-stabilization. Ligaments, along with underyling bony architecture, set the natural limits for the range of most joints in the human body.
Our vertebral bones are attached to each other by ligaments, which provide the passive structure to keep our spines stable. Spinal ligaments are over-stretched either by blunt trauma that bends the spine (e.g. motor vehicle accidents), OR by the kind of repetitive, forceful or sudden stretching that can occur deliberately or accidentally in certain tasks, dance moves, yoga postures, and recreational activities.
I’m not knocking dance or yoga per se, because some dance styles and yoga poses emphasize maintaining the spine in neutral position against gravity, such as many ballroom styles and yoga’s “plank,” “side-plank,” and “tree” poses. These poses, and other core stabilization exercises such as I teach to patients, and are taught in physical therapy and pilates, strengthen key core muscle groups and protect the spine. Also, some yoga stretches safely elongate muscles that often need to be stretched, without de-stabilizing joints. Calf and hamstring stretches, properly performed, are examples of muscles streches that benefit almost everyone. More on the distinction between mobilization vs. stretching vs. strenghtening below…)
When the ligaments attaching one vertebrae to the next get over-stretched, the result is a hyper-mobile spine that places more load on the intervertebral disc at that segement of the spine. Spinal inter-vertebral discs are made of a special kind of ligamentous tissue, including a shock-absorbing gel in the middle, and can be injured by both compressive and shearing forces. Those forces are greatly increased if the other adjacent supportive ligaments are loose and lax from over-stretching.
Bending the spine becomes most risky when done abruptly, repetitively, forcefully, or ballistically, and even more so when a heavy external load is involved. Common ways that people injure their backs include bending forward with knees straight, and then picking up a weight off the floor–particularly if adding a twist or rotation in the spine at the same time. So we can see why digging dirt out of trench, or chucking logs into the back of a truck, are particularly infamous for back injuries–they involve rapid, forceful, ballistic loading of the spine while bending and twisting at the same time.
Organizing time and tasks, and getting help where needed, to avoid high-speed, high-load and repetitive bending, lifting and twisting can save spines from significant and sometimes irreparable damage!
Understanding the distinction between mobilizing vs. stretching is important to preventing back injury. By mobilizing, I mean moving the spine within its ligament-defined limits. By stretching, I mean an attempt to expand one’s natural range of motion, which inevitably involves stretching ligaments. While moving the spine is beneficial, the purported benefits of stretching the spine are not found in either studies of back pain nor in clinical experience. Learning to move the spine while staying within the natural limits defined by its discs and ligaments is important for its health and longevity. Note that these natural limits form a bell curve across populations, and naturally decline with age–thus what one 19-year old yogini or figure-skater can do to bend their back could be disastrous for a different 19-year old, as well as for most 60 year-olds.
So why does stretching our backs feel good? This is a tricky subject that is counter-intuitive and requires some elaboration. For starters, if we stay within our range-of-motion, we aren’t technically stretching, we’re just mobilizing, which increases blood flow to muscles and lubricates joints and tendons and makes us feel good–no problem. Stretching also feels good, temporarily, because stretching also increases blood flow and lubricates joints, and the very discomfort of an extreme stretch releases endorphins, our body’s natural pain-killing response, which gives us the sort of athletic “high” experienced during running and other forms of exertion.
This endogenous stretcher’s “high” can mask the underlying weakening of spinal discs and ligaments that is taking place during the stretch. In response to weakened structure, spinal reflexes cause muscles to tighten in a sub-conscious effort to splint the area and prevent injury. The resultant muscle tension feels bad, leading to an increased urge to stretch–a vicious cycle that results in the paradox of a weak and unstable spine, overlaid by chronically tight muscles that feel like they need to be further stretched.
What if, instead, we strengthen rather than stretch our trunk muscles? The vicious cycle is replaced by a healthy one–good muscular control and support protect the spine and reduced the feelings of tension and the urge to stretch. And indeed, many studies support the benefits of strengthening vs. stretching the muscles of the low back and spine. I invite my patients and the public to try this approach, which is embodied in physical therapy, taiji, and many Pilates exercises, and which I teach in my clinic.
Excess body weight increases stresses and compressive forces and on the lumbar spine. Body weight carried above the low back puts particular axial loading on the lumbar disks that serve to cushion vertical forces. Imagine driving a car that is over-loaded (e.g. too many passengers, etc.)–notice how you feel road bumps much more than if the car is lightly loaded? The shock absorbers can’t handle the extra weight, fail to cushion the ride, and wear out faster…the lumbar spine is no different, except that artificial disk replacement surgery is much riskier, with less satisfactory outcomes and costs tens of thousands of times higher than replacing worn-out shocks!
In addition, the effect of gravity is to pull a protruding abdomen (e.g. a “beer belly”) down and forward, making the lumbar spine over-arch and causing the back muscles to over-work to maintain an upright position. In addition, having an arched low back compresses the lumbar “facets,” small joints on either side of the spine that have a lot of nerve endings and send out strong pain signals when sprained! Both the back muscles and lumbar facets can become chronically sore and inflammed from the strain of carrying excess body weight.
Prolonged sitting and driving
We are all generally aware that the sitting and driving required by modern society has it price. When sitting, the low back in particular suffers from a combination of:
- Axial loading of the discs (as described above) and alteration of the normal lumbar curves.
- Immobilization and compression of muscles and connective tissue, leading to muscle weakness, decreased blood flow and lymph drainage, and reduced neuro-muscular control.
- High-speed vibration during driving. Our tissues evolved in the pre-industrial era when they were never subjected to the rapid vibrations and low-amplitued, high-speed shear forces that can be produced by our modern machines.
Many of us are thus faced with a social and technological challenge in avoiding prolonged sitting and driving. Understanding that we have varying degrees of control over our (and others) work tasks, work statsions, and social lives, we can at least consider and try the following:
- Taking even short breaks every hour to get up and walk around helps to keep body weight down and undo the damage of sedentarianism…
- Making wireless technology a plus by re-configuring work tasks and tools to facilitate standing or walking while working–on raised desks, or treadmills with a laptop, or walking while talking in person or on mobile phones (held at a safe distance to minimize microwave radiation exposure)…
- Minimizing unecessary sitting whenever possible by planning for active rather than seated social events, recreation and family time….
- Using alternatives to driving for transportation…
- Walking whenever possible. Walking benefits not only body weight, but also spinal discs and joints and bone density and muscle tone in the legs. Walking is what our human bodies are evolved to do!
Though we may not be able to or want to go back to all the types of physical activity that used to be involved with work, we can at least think creatively about how to keep ourselves, or employees and/or co-workers, and our culture moving and using our bodies while we work…and play…for our collective health and well-being!
Maintaining good overall tissue health is also important for preventing and recovering from back pain.
A pro-inflammatory diet high in cholesterol, refined carbohydrates and trans-fats, and low in essential fatty acids all have adverse effects on the resiliancy and self-repair capabilities of muscle, connective, and joint tissue, as well as on blood supply and lymph drainage. Conversely, a diet rich in essential fatty acids helps to reduce tissue inflammation.
Smoking, in particular, has been shown to acidify the pH of spinal discs, such that when they get injured and their fluid leaks into the surrounding tissue, the pain is made even more burning and intense by the acidity of the smoker’s disk!
Physical activity in general is important for promoting blood circulation through tissue, which brings in oxygen and nutrients and carries away wastes. Physical activity involving the legs and trunk muscles maintains their strength, flexibility, lymph drainage, and nerve and blood supply, all of which are essential for tissue self-repair.
Finally, being chronically under psycho-social stress releases excess salivary cortisol, which actually breaks down muscle and connective tissue, leading to weakness, poor control, and decreased self-healing ability. Depression and workplace stress have a clear associations with low back pain. If back pain and stress/depressoin both are present, both deserve treatment, and treatment of both works better than treatment of one alone. Maintaining a positive and optimistic outlook on life, and making necessary changes to reduce and manage stress, is one of the best things you can do for your low back!
Seeking relief from low back pain?
Please call the clinic at 831-459-6762 for further information or to schedule an appointment.