A Most Common Affliction: Lower Back Pain (Part 1)

Pain from the lower part of our bony spine is known as Low Back Pain (LBP). In the CARP survey we ran a couple of months ago (for more details on this see my past column, Too many people hurt) , 21% of all respondents aged 55 and over stated that they had chronic back pain. Not all back pains are the same. In a 3-part series I will discuss the different causes of back pain, as well as available treatments, since back pain is a significant problem for many people.

Let me give examples first of people who can present with different causes of LBP.

#1.Mr. G. is 45 years old, overweight, and works as an accountant. He spends several hours a day sitting in front of his computer and has little physical activity. He complains of ongoing LBP that waxes and wanes. A
couple of times he had to stay in bed for a few days as the pain had become excruciating.
#2. Ms. A. is 42 years old, has been in a physically and emotionally abusive marriage for years and is now going through a bad divorce. She visits her family doctor often complaining of back pain, as well other pain problems such as headaches and tummy aches.
#3. Mr. T. is 32 year old construction worker. He fell backwards and experienced serious and acute LBP radiating to the right leg with numbness in his big toe.
#4. Mr. F. is 75 years old. He has had low grade back pain for at least 20 years. Over the last year, however, the pain has become stronger while his legs hurt when he walks. He relieves back and leg pain when he sits down for a few minutes.
#5. Mrs. L. is 63 years old and has been smoking since she was 17. Lately she has noticed weight loss, fatigue and back pain that keeps her awake at night.
#6. Mrs. F. is 69 years old and has been told she has osteoporosis. She experiences sudden onset of excruciating pain in her back after she lost her footing on the staircase. She did not fall but she jerked herself hard.

All these people have back pain, but the causes differ. Mr. G. is unfit with weak abdominal and back muscles living a sedentary life. Mrs. A. seems to experience not only LBP but also other symptoms under great stress. Mr.T. suffers from what seems to be a herniated disc. Mr. F. seems to be bothered by leg pain while walking, a sign of very narrow spine due to serious wear and tear and pinched nerves (called in medical terms “spinal stenosis”). Mrs. L’s doctor is seriously worried about possible cancer in her bones, since she is a heavy smoker. Mrs. F. in all likelihood has sustained a fracture in her spine as her bones are weak.

So, LBP can have many causes. However, the very bad ones (cancer, seriously pinched nerves, fracture etc) are quite rare as compared to the very common “non specific LBP”, like the one Mr. G. and Mrs. A. had. These are the things we should know about non specific low back pain.

• LBP is the most common cause of disability for workers younger than 45 years of age.
• Back pain is one of the commonest reasons for visiting the family physician
• LBP is very costly. 10% of the work-related claims for back injury are responsible for 80% of money spent to cover time-off work, disability and medical costs.
• For the vast majority of people (over 90%) an episode of back pain will limit activity for less than 30 days.
• About 25-40% of people with an episode of LBP, may have symptoms that look like sciatica (pain radiating down to the leg), but only 1 in 10 of those with “sciatica” symptoms will have a true herniated disc (in other words, the overwhelming majority does NOT have a Herniated disc).
• Even when there is a true disc herniation, more than half of the sufferers will recover on their own and will not need any surgery.
• Back problems are nearly unavoidable by age of 50 years, but their severity and intrusiveness varies extensively between different people.
• One thing we should remember is that there is no typical, easily identifiable cause for the vast majority of patients. Pulled muscles, strained ligaments, tight joints or small tears in the disks (shock absorbers which are stacked between the spine bones) are all likely causes.
• Factors that increase the chance to get LBP include obesity, lack of exercise, heavy physical work, accidents, vibration (i.e., driving a truck), smoking, and family history.

Unfortunately, the treatment and understanding of back pain has been characterized for many years by irrational approaches and misconceptions as follows:

• X-rays give very rarely additional information (beyond that extracted by a good history and physical examination). Unless there is a very specific reason (such as suspicion of infection, fracture or cancer), your doctor should not order X-rays for you.
• Wear and tear changes on computed axial tomography (CAT scan) or magnetic resonance imaging (MRI), occur very commonly and they do not mean that something is “wrong with our back”. For example, a 50 year old person has a 50% chance to have some abnormal findings in a CAT scan or MRI, and a 70% chance of abnormal x-rays , without any symptoms whatsoever.

In most cases, findings on the X-rays or the CAT scan or MRI are of NO VALUE unless the history and the physical examination point to specific problems.

In the next column we will discuss in more detail what we should do in the case of an attack of LBP versus chronic LBP.

Angela Mailis Gagnon, MD, MSc, FRCPC(PhysMed)
Director, Comprehensive Pain Program,
Senior Investigator, Krembil Neuroscience Centre
Toronto Western Hospital,
Chair ACTION Ontario www.actionontario.ca

Keywords: pain, treatment