Why Does Your Lower Back Hurt When Lying Down Flat?

Back pain – a common ailment among adults in the US – can be caused by many factors. Finding out why your lower back hurts is important for finding a solution. Some key points to consider include the location of your pain and what might be contributing to it.

A frequent complaint is lower back pain when lying down flat. If you've experienced this type of pain, you’ll understand that the pain can come and go. As a result, it can be difficult to identify the source of your symptoms. Below, we'll discuss some of the most common causes of lower back pain that occurs when lying down flat.

What could cause lower back pain when lying down flat?

Several different things may cause back pain when you lie down flat. Here are some of the most common causes:

Strain or sprain

When you stretch or tear a ligament, it results in a sprain. A strain is similar, but it occurs in a muscle or tendon. Strains or sprains can result in pain, tenderness in the area, swelling, or bruising. These types of injuries are quite common and can occur as a result of overwork or overexertion during exercise or other physical activities.

Sciatica

The sciatic nerve is the widest and longest nerve in the body. It starts at the base of the spine and continues down the back of each leg, eventually ending in the foot. If this nerve gets pinched, compressed, or irritated, it can cause a condition called sciatica. You could have sciatica if you experience burning, numbness, or shooting pain that starts in your lower back and radiates down the leg.

Arthritis

Arthritis comes in many forms, some of which may cause lower back pain. Osteoarthritis is common among older adults and can cause pain and stiffness in the lower spine. Another type of arthritis that specifically affects the spine is ankylosing spondylitis.  Although similar to osteoarthritis, this condition is commonly diagnosed in those between the ages of 20-30.

Spinal stenosis

Several factors¹ contribute to the narrowing of the spaces in your spine. These changes can cause pressure on the nerve, which may lead to symptoms, such as tingling and weakness down the legs. Many people experience worsening pain in extended positions, such as standing or lying.

Spinal tumor

Spinal tumors can be benign (non-cancerous) or malignant (cancerous) and can put pressure on nerves causing pain when lying flat.

Degenerative disc disease

Over time, wear and tear on your body may cause the discs between the vertebrae of your spine to start degrading. These changes can cause bone-on-bone friction, which eventually leads to pain.

However, there are other conditions that may cause lower back pain when you lie down flat, so it's best to see your doctor for a diagnosis.

How can you help relieve back pain when lying down flat?

If you experience lower back pain when lying down flat, it can disrupt your sleep. Being in constant pain can prevent your ability to relax and prepare for a good night’s rest. Fortunately, there are certain ways around this problem. Here are a few things to try:

NSAIDs

Non-steroidal anti-inflammatory drugs can help to reduce pain and swelling. Aspirin, Motrin, and Advil are common NSAIDs, among others. This can be an option for treating inflammatory lower back pain, especially if it's occurring due to a strain or sprain. There are also topical NSAIDs that you can rub directly onto the painful spot.

Heat

Electric heating pads or disposable heat packs are great for relieving muscle aches or joint pain. Circulating heat can soothe these irritated areas and improve recovery by increasing blood flow.

Support your spine

When lying flat, it may help to put a rolled-up towel or pillow under your knees, lower legs, and/or lower back to help the spine find a comfortable position.

Massage therapy

A massage can help loosen tight muscles and relieve pressure on the nerve. A trained and licensed professional will know the right locations on which to apply pressure to treat the affected areas.

Gentle stretching

Gently stretching and exercising the muscles in your back may help alleviate some mild pain. Be sure to avoid overdoing it, though. Repeating the same movement too much can fatigue your back and even make your original problem worse.

When should you see a doctor?

If you have sharp, sudden, or severe lower back pain that doesn't go away, it's best to see your doctor as soon as possible. Your doctor can help provide you with a diagnosis and rule out any serious or life-threatening conditions.

In addition, if your back pain is getting in the way of your life or making it difficult to sleep, you should schedule an appointment with your doctor. Your doctor is likely to perform a physical examination and may recommend further diagnostic tests like an x-ray or MRI. These tests are sometimes needed to make an accurate diagnosis.

Once your doctor better understands the problem you're facing, you can collaboratively develop an appropriate action plan. This may involve seeing a back and spine specialist, physical therapist,  taking prescription medication, or even surgery.

If lower back pain while lying flat is negatively impacting your life, a doctor can help. Back pain is treatable, and it's not something you should just ignore.

The lowdown

Lower back pain when lying down is a common problem that may have a number of root causes. If you experience lower back pain when lying down, it's advised to seek your doctor’s expertise to determine what could be causing your symptoms. Although most episodes of back pain are not serious, it could also be a sign of something more serious.

If you have mild back pain when lying down, it may help to take over-the-counter pain medications or apply heat to the affected area. Massages and proper spine support can also help. In more extreme cases, your doctor may provide you with prescription medications to help ease your back pain. However, the majority of lower back pain may go away on its own and can be easily managed.