Being overweight is not easy. People who carry higher than normal weight have more health problems and spend much more money and energy to deal with those health problems over a lifetime than people with normal weight do.
When it comes to lower back pain, obesity strikes a one-two punch. The first punch is that people who are overweight are more likely to have lower back pain and lumbar spine symptoms. The second punch comes after lumbar spine surgery. People who are overweight and obese have a greater risk of complications from and after surgery.
Defining overweight and obesity
While it is far from perfect, physicians use body mass index or BMI to determine if a person is underweight, normal weight, overweight, or obese. You can calculate your own BMI by dividing your weight in kilograms by your height in meters squared (or use an online BMI calculator). The BMI above 25 kg/m2 is considered overweight, a BMI of 30 and above is obese, and a BMI 40 and above is considered morbidly obese. One can quibble about these numbers, especially considering that 70% of American adults are overweight or obese; however, the fact that the risk of many diseases increases substantially at a BMI greater than 25.
Excess weight and lower back pain
Unlike high blood pressure, diabetes, and coronary artery disease, lower back pain is not directly tied to excess weight. Nonetheless, patients who are overweight or obese are more likely to have lower back pain. Moreover, people who are overweight are more likely to have joint pain and muscle strain than normal weight individuals. As people gain more weight, cardiovascular exercise becomes more challenging, which in turn causes more weight gain—and the cycle continues. With a lack of exercise comes a lack of core muscle strength and flexibility, which can further increase the risk of lower back pain.
Excess weight and lower back surgery
Many people with chronic low back pain will ultimately need some sort of back surgery, usually a lumbar spine surgical procedure. Researchers examined records from over 24,000 lumbar spine procedures between the years of 2006 and 2011.1 Of these, nearly 80% were performed on people with BMI values in the overweight, obese, and morbidly obese categories.
They found that lumbar surgical procedures took significantly longer in overweight individuals.Overweight people require longer durations of anesthesia than normal weightpeople do. Patients with a BMI higher than 25 kg/m2 had substantially greater risk of deep vein thrombosis (dangerous blood clot in the leg), pulmonary embolism (dangerous blood clot in the lung), and wound infection. Morbidly obese patients (BMI ≥40 kg/m2) had an increased risk of acute renal (kidney) failure, sepsis (serious blood infection), and urinary tract infection.
Fortunately, being overweight or obese did not prolong hospitalization after lumbar spinal surgery, nor was it associated with any increased risk of death.
Stopping the cycle
Fortunately, people who can manage to return to a normal weight or can avoid becoming overweight or obese in the first placecan reduce their risk of having lower back pain. Once chronic back pain starts, it is substantially more difficult to lose weight, not simply because of a lack of physical conditioning, but back pain can interfere with the ability to exercise. Targeted physical therapy may help minimize back pain. Moreover, the physical therapist may be able to suggest customized exercises (e.g., water sports, walking). A registered dietitian can suggest a dietary regimen that is nutritious, tasty, and can promote weight loss. If these measures fail, obese individuals—especially those with obesity related complications—may want to consider bariatric surgery (weight loss surgery) before undergoing a lumbar spine procedure.
- Marquez-Lara A, Nandyala SV, Sankaranarayanan S, Noureldin M, Singh K. Body mass index as a predictor of complications and mortality after lumbar spine surgery. Spine (Phila Pa 1976). May 1 2014;39(10):798-804. doi:10.1097/brs.0000000000000232