Our spines are remarkable; they are incredibly intricate systems of bones, ligaments, tendons, and muscles all working together to allow us to move in complicated ways.
Even the slightest micro-motion at a specific spinal segment can cause pain when something is wrong.
If it hurts to move, it helps to understand what is happening in the spine so you can better communicate to your physician. Hopefully, the better the communication, the faster you will find a treatment that works.
Here are the 5 most common reasons motion causes back pain:
1. Large spinal muscles are easily strained with twisting motions
The most common reason motion will cause back or neck pain has nothing to do with the spinal structure at all.
The muscles or ligaments surrounding the spine in the back or neck can become over-stretched or even torn. This causes inflammation and pain while the body tries to limit motion while it heals.
2. Motion in the lower spine can lead to pain
Of the four major regions of the spine, the lumbar spine (lower back) has a lot of motion and carries all the weight of the torso, making it the most frequently injured area of the spine.
The motion in the lower back is divided between five vertebral motion segments (each of which are comprised of 2 cartilage-covered facet joints and a disc), although a disproportionate amount of the motion is in the lower segments (L3-L4, L4-L5, L5-S-1).
The two lowest discs (L4-L5 and L5-S1) endure the most strain and are the most likely to become herniated. This can cause pain and possibly numbness that radiates through the leg and down to the foot (sciatica).
- For more on sciatica, see What You Need to Know About Sciatica.
3. Motion can lead to cartilage breakdown
Spinal arthritis is relatively common and is most likely to occur in people over age fifty. Spinal osteoarthritis is the mechanical breakdown of the cartilage between the aligning facet joints in the back portion of the spine.
The facet joints become inflamed, and progressive joint degeneration creates more frictional pain. As the back pain progresses, the motion and flexibility of the spine decreases.
- More stiffness and pain in the lower spine in the mornings and later in the day.
- More stiffness and pain in sacroiliac joint in the mornings and later in the day.
- Decreased pain during the day as normal movements stir the fluid lubricant of the joints.
- Low back pain radiating to the pelvis, buttocks, or thighs and sometimes to the groin.
4. Bone spurs can form to compensate for too much motion
With osteoarthritis, bone spurs (small irregular growths on the bone, also called osteophytes) typically form on the facet joints in response to joint instability (from the degeneration).
Bone spurs can be a normal part of aging and do not directly cause pain. They may become large enough to cause irritation or entrapment of nerves passing through spinal structures, and this may result in diminished room for the nerves to pass (stenosis).
Most cases will produce pain (and perhaps numbness and tingling) into the legs with walking, and the pain will be relieved with sitting.
Over time, degeneration of the facet joints in the lower back can result in formation of a fluid-filled sac called a synovial cyst. These cysts are benign, but if they put pressure on the spinal canal they can, like bone spurs, cause symptoms of spinal stenosis.
5. Disc degeneration leads to pain from micro-motion
Symptomatic degenerative disc disease creates excessive micro-motion at a vertebral level and leads to pain.
Common symptoms of degenerative disc disease include:
- Low back pain that generally worsens with sitting.
- Certain types of activity usually worsen low back pain, especially bending, lifting, and twisting.
- Walking, and even running, may actually feel better than prolonged sitting or standing.
- Patients generally feel better if they change positions frequently, and lying down is usually most comfortable.
With a better understanding of the pain associated with motion segment disorders, you can better describe your symptoms and help your doctors more accurately identify the specific cause of the pain.
In addition to the resources referenced above, articles like Preparing to Meet with a Spine Surgeon or Spine Specialist could help you work with your doctor to more quickly develop an appropriate treatment plan for the segment of your spine creating pain during motion.