Five Reasons Your Lower Back Hurts

Almost everyone will experience lower back pain at some point in their lifetime. 

For some, it’s on the level of a nagging annoyance, but for others, everyday activities -- like hoisting your toddler to your hip or stretching to reach that shoe under your bed -- will send you into severe pain and can seriously impact your quality of life.

Your lower back is made up of a complex combination of muscles, tendons, vertebrae and joints, making this area especially susceptible to strains, sprains and other injuries. Lower back pain is the 2nd most common cause of doctor office visits in the U.S. and can be either acute or chronic. Acute pain is a normal immediate response to an injury. Chronic pain is defined as pain that lasts more than 12 weeks. Whether constant or intermittent, chronic pain can point to an underlying issue such as joint degeneration, inflammation, ligament damage or other problem that may require intervention.

Here are some common reasons you may be experiencing lower back pain:

1. Muscle or Ligament Strain

According to the Mayo Clinic, repeated strain from lifting, or sudden, awkward movements can injure muscles and ligaments in the back and spine. Overexertion for those who have weakened muscles or are out of shape can lead to painful muscle spasms.[1]

Sometimes the cause is obvious, like an injury at the gym or a spill while ice-skating, but there can also be underlying issues at play if pain persists for long periods of time or doesn’t respond to treatment.

2. Child Birth 

For women who have recently given birth, the sore and achy lower back of pregnancy may not yet be a thing of the past.

During pregnancy, hormones signal your joints to loosen in preparation for delivery. In addition, the weight of baby and the weakened or stretched abdominal muscles may place strain on the back ­– and these things take time to heal.[2]

It’s also possible that while passing through the birth canal, baby can injure the ligaments or muscles of the pelvic floor or injure mom’s tailbone.[3] The SI joint (where your spine and pelvis meet) is also susceptible to injury from pregnancy and childbirth (learn more below).

Keep in mind that while some soreness and discomfort may be a normal result of delivery, severe or continued pain is always a reason to speak with your health care provider.

3. SI Joint Dysfunction

Do you have pain in your hip, lower back, pelvis or buttocks? You may be experiencing sacroiliac (SI) joint dysfunction. This overlooked but common source of pain impacts 15-30% of people with chronic lower back pain.[4],[5],[6],[7],[8]  As with other joints in the body, the SI joint can become damaged from trauma, degeneration and everyday wear and tear. Everything from motor vehicle accidents, falls, lifting and twisting, natural childbirth and pregnancy, as well as conditions that lead to degeneration such as osteoarthritis, previous lumbar spine surgery, or prior joint infection can cause SI joint dysfunction.

Thankfully, there are surgical advances and treatments that can provide lasting relief of these symptoms. If you are experiencing chronic lower back pain, consider taking this short quiz to see if SI joint dysfunction may be causing your lower back pain. 

4. Herniated Disc 

A herniated disc (also referred to as a slipped disk or disk prolapse) is a common condition in which the soft, malleable interior (nucleus pulposis) of a spinal disk – the pads between spinal vertebrae that provide cushioning and stability – protrudes though a tear in the tough outer casing (annulus).

A herniated disc can be caused by normal wear and tear or improper lifting or overexertion. While it may be excruciatingly painful, particularly if it is creating pressure against a nerve in the spine, there are also times when there is no pain at all and the only noticeable symptom is numbness or tingling in an affected limb.[9]

Aside from strain and overuse, being overweight and poor muscle tone are also risk factors.[10] If you’re experiencing radiating pain, weakness or numbness in one or more limbs, see a healthcare provider to determine whether a herniated disc could be the source of your troubles.

5. Arthritis in the Spine 

You probably know that arthritis can cause stiffening and pain in hands and feet, but many people aren’t aware that it can also affect the spine. Each vertebra in the spine is linked to the vertebra above and the vertebra below by two facet joints and an intervertebral disc. Like other joints in the body, facet joints can be susceptible to degeneration and inflammation, and this can result in significant back pain.

As we age, thinning cartilage, or bone spurs can cause facet joints to become less mobile. Over time, this may lead to irritated, inflamed and painful joints that send pain signals to the brain. Once it has set in, facet arthritis cannot be reversed – but lifestyle changes can help improve pain and mobility, and procedures to reduce or interrupt pain signals are available.[11]

What You Can Do 

Rest, stretching, alternating hot and cold applications, and pain medicine are often used to ease lower back pain but results vary from person to person and injury to injury.

For pain that doesn’t respond to therapeutic care at home, it’s likely time to see a clinician such as a physical therapist, pelvic health specialist or pain management specialist who can conduct a physical exam or request imaging studies to identify the source of the problem.

Only your doctor can determine the best course of treatment for you. The information above is not treatment advice and SI-BONE does not recommend or endorse any particular course of treatment or medical choice. Talk to your doctor about your treatment options.

Need More Help?

More Related Resources

More links and information regarding the diagnosis and treatment of SI Joint Pain:

[1] “Back Pain.” Mayo Clinic, Mayo Foundation for Medical Education and Research, 4 Aug. 2018, www.mayoclinic.org/diseases-conditions/back-pain/symptoms-causes/syc-20369906.

[2] BabyCenter, and BabyCenter Medical Advisory Board. “Postpartum Back Pain: How to Get Relief.” BabyCenter, www.babycenter.com/0_postpartum-back-pain-how-to-get-relief_1152191.bc.

[3] “Postpartum Pelvic Bone Problems & Pelvic Pain After Childbirth.” WebMD, www.webmd.com/women/pelvic-bone-problems-after-childbirth#1.

[4] Bernard TN, Kirkaldy-Willis WH. Recognizing specific characteristics of nonspecific low back pain. Clin Orthop. 1987:266–80.


[5] Schwarzer AC, Aprill CN, Bogduk N. The sacroiliac joint in chronic low back pain. Spine. 1995;20:31–7.


[6] Maigne JY, Aivaliklis A, Pfefer F. Results of sacroiliac joint double block and value of sacroiliac pain provocation tests in 54 patients with low back pain. Spine. 1996;21:1889–92. http://www.ncbi.nlm.nih.gov/pubmed/8875721.

[7] Irwin RW, Watson T, Minick RP, Ambrosius WT. Age, Body Mass Index, and Gender Differences in Sacroiliac Joint Pathology. Am J Phys Med Rehabil. 2007;86:37–44. doi:10.1097/PHM.0b013e31802b8554. http://www.ncbi.nlm.nih.gov/pubmed/17304687.

[8] Sembrano JN, Polly DW. How often is low back pain not coming from the back? Spine. 2009;34:E27–32. doi:10.1097/BRS.0b013e31818b8882. http://www.ncbi.nlm.nih.gov/pubmed/19127145.

[9] “Top Cause of Low Back Pain.” WebMD, https://www.webmd.com/back-pain/features/causes#1

[10] “Low Back Pain Fact Sheet.” National Institute of Neurological Disorders and Stroke, U.S. Department of Health and Human Services, www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Low-Back-Pain-Fact-Sheet#3102_4.

[11] Berry, Jennifer. “Facet Arthropathy: Symptoms, Causes, and Risk Factors.” Medical News Today, MediLexicon International, www.medicalnewstoday.com/articles/320355.php.

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