Side pain, often referred to medically as flank pain, can be a puzzling and uncomfortable experience. If you’re experiencing pain in the mid-back region, on either side of your body, you might be wondering, “Why Would My Side Hurt?”. It’s a common concern, as back pain in general affects a significant portion of the population at some point in their lives. While sometimes side pain may be due to a simple muscle strain, it can also signal a more serious underlying medical condition.
Your flanks are defined as the areas on the sides of your body, extending from your upper abdomen to your back. Discomfort in this region, whether on the right or left side, requires attention to pinpoint the cause. Let’s explore five potential reasons why you might be experiencing side pain.
A man experiencing flank pain, holding his left side.
1. Degenerative Disc Disease: A Common Cause of Side Pain
One of the prevalent culprits behind side pain is degenerative disc disease. This condition arises from the wear and tear of the intervertebral discs, the spongy cushions located between the 26 vertebrae of your spine. As we age, these discs can naturally dehydrate and flatten, leading to pain. In more severe cases, these discs can rupture or bulge, commonly known as a herniated or slipped disc.
According to Christopher C. Ornelas, MD, a spine specialist at Keck Medicine of USC and assistant professor of clinical orthopedic surgery at the Keck School of Medicine of USC, “When a disc degenerates, the spaces where nerves exit the spine can narrow, and the spinal joints may become compressed. This process can irritate the nerves, causing pain that radiates to the flank area, resulting in side pain.”
Symptoms of Degenerative Disc Disease:
- Side pain or flank pain, which may radiate to the hips or legs.
- Pain that worsens with certain movements, like bending, twisting, or lifting.
- Numbness or tingling in the legs or feet.
- Muscle weakness in the legs.
Diagnosis and Treatment:
If your symptoms suggest degenerative disc disease, your doctor may recommend imaging tests to confirm the diagnosis. Initially, an X-ray might suffice. However, for persistent pain or pain accompanied by weakness, an MRI of the mid or lower spine might be necessary to get a detailed view of the soft tissues and nerves.
Treatment options range from conservative approaches to surgery, depending on the severity:
- Rest: Avoiding activities that aggravate the pain.
- Medications: Pain relievers, anti-inflammatory drugs, and muscle relaxants.
- Physical Therapy: Exercises to strengthen back muscles, improve flexibility, and reduce pain.
- Spinal Injections: Corticosteroid injections to reduce inflammation and pain.
- Surgery: In severe cases where conservative treatments fail, surgery may be considered to relieve nerve compression and stabilize the spine.
2. Osteoarthritis of the Spine: Joint Wear and Tear Leading to Side Discomfort
Osteoarthritis, a common type of arthritis, can also affect the spine. In osteoarthritis of the spine, the protective cartilage in the spinal joints breaks down over time. This cartilage erosion can irritate the spinal nerves, causing inflammation and pain that can manifest as side pain.
Dr. Ornelas further explains that osteoarthritis in the spine can sometimes lead to the formation of bone spurs. These bony growths can contribute to another condition called spinal stenosis, where the spinal canal narrows, potentially compressing the spinal cord and nerve roots. This compression can also cause pain that radiates to the side.
Symptoms of Osteoarthritis of the Spine:
- Side pain that may worsen with activity and improve with rest.
- Stiffness in the back, especially in the morning or after periods of inactivity.
- Pain that may radiate to the buttocks or thighs.
- In cases of spinal stenosis, potential numbness, weakness, or tingling in the legs or feet.
Diagnosis and Treatment:
Diagnosis typically involves a physical exam, review of symptoms, and imaging tests such as X-rays, CT scans, or MRI scans to visualize the spine and assess the extent of cartilage damage and bone spur formation.
Treatment for osteoarthritis of the spine aims to manage pain and improve function. Non-surgical options are often effective:
- Physical Therapy: Exercises to strengthen muscles, improve flexibility, and reduce pain.
- Pain Medications: Over-the-counter or prescription pain relievers and anti-inflammatory drugs.
- Braces: Back braces can provide support and limit motion, reducing pain.
- Injections: Corticosteroid injections can help reduce inflammation and pain.
- Surgery: If non-surgical treatments are insufficient, surgery may be considered to decompress the spinal canal or stabilize the spine.
3. Pulled Muscle: Side Pain from Strain and Overexertion
A pulled muscle, or muscle strain, is a common cause of sudden side pain, especially after physical activity. If you’ve recently engaged in strenuous exercise, lifted heavy objects, or even spent extended periods in awkward postures, you may have strained a muscle in your flank area. Even prolonged sitting can sometimes irritate these muscles.
“It’s crucial to recognize that the muscles in the flank region can be strained and irritated by activities like lifting, bending, or twisting. Sometimes, even prolonged sitting can lead to muscle irritation in this area,” Dr. Ornelas notes.
Symptoms of a Pulled Muscle in the Side:
- Sudden onset of side pain, often after a specific activity.
- Muscle tenderness to the touch.
- Muscle spasms.
- Limited range of motion due to pain.
Treatment for a Pulled Muscle:
Most pulled muscles in the side heal with self-care measures:
- Rest: Avoid activities that aggravate the pain.
- Ice: Apply ice packs to the affected area for 15-20 minutes at a time, several times a day, to reduce inflammation.
- Heat: After the initial inflammation subsides (usually after 48-72 hours), heat can help relax muscles and relieve pain.
- Pain Relievers: Over-the-counter pain relievers like ibuprofen or acetaminophen can help manage pain.
- Gentle Stretching: Light stretching exercises can help improve flexibility and promote healing, but avoid stretching if it increases pain.
If the pain is severe, doesn’t improve with home care within a few days, or is accompanied by other concerning symptoms, it’s important to seek medical advice.
4. Kidney Issues: Pain Originating from Within
Sometimes, side pain may not be related to your back at all but could stem from your kidneys. Your kidneys are located on each side of your spine, just below your rib cage, making them a potential source of flank pain.
Kidney Stones: One of the hallmark symptoms of kidney stones is intense, sharp pain that often starts in the back or side and can radiate to the groin. This pain occurs as kidney stones move through the urinary tract.
Kidney Infections (Pyelonephritis): Kidney infections, which can occur when a urinary tract infection (UTI) ascends to the kidneys, can also cause significant side pain.
Symptoms of Kidney Issues Causing Side Pain:
- Kidney Stones:
- Severe, sharp pain in the side and back, often radiating to the lower abdomen and groin.
- Pain that comes in waves and fluctuates in intensity.
- Blood in the urine.
- Nausea and vomiting.
- Frequent urination.
- Painful urination.
- Kidney Infections:
- Side pain or flank pain.
- Fever and chills.
- Painful urination.
- Frequent urination.
- Nausea and vomiting.
- Cloudy or foul-smelling urine.
Diagnosis and Treatment:
If kidney issues are suspected, your doctor will perform a physical exam and urine tests. Imaging tests like CT scans or ultrasounds may be used to diagnose kidney stones or infections.
Treatment depends on the specific kidney problem:
- Kidney Stones: Treatment can range from pain management and increased fluid intake to allow the stone to pass naturally, to procedures like shock wave lithotripsy or surgery to break up or remove larger stones.
- Kidney Infections: Kidney infections require prompt treatment with antibiotics to clear the infection and prevent complications.
5. Shingles and Other Conditions: Less Common Causes of Side Pain
Shingles: If your side pain is accompanied by a rash on one side of your body, it could be shingles. Shingles is caused by the varicella-zoster virus, the same virus that causes chickenpox. After a chickenpox infection, the virus can lie dormant in nerve tissue and reactivate later in life as shingles, causing nerve pain and a characteristic rash.
Other Conditions: While less common, side pain can also be associated with liver disease or gastrointestinal problems. Pain from these conditions may sometimes radiate to the flank area.
Symptoms of Shingles:
- Side pain or flank pain, often described as burning, tingling, or stabbing.
- Rash that develops on one side of the body, typically in a band or stripe pattern.
- Fluid-filled blisters that break open and crust over.
- Itching, tingling, or numbness in the affected area.
- Fever, headache, and fatigue.
When to Seek Medical Attention:
While this article provides potential reasons for “why would my side hurt?”, it’s crucial to consult a healthcare professional for an accurate diagnosis and appropriate treatment. If you experience side pain that:
- Is persistent and doesn’t go away.
- Is severe or unbearable.
- Is accompanied by other symptoms like fever, chills, rash, nausea, vomiting, painful urination, or weakness.
It is always best to seek medical advice to rule out serious conditions and receive personalized care.
Connect With Our Spine Experts
If you’re experiencing persistent side pain, especially if you suspect it might be related to a spine condition, the spine surgeons at Keck Medicine of USC offer comprehensive and tailored treatment options. They specialize in a range of spine conditions and injuries, including degenerative disc disease, herniated discs, and more.
Learn more about our Spine Center
Topics: arthritis, degenerative disc disease, Dr. Christopher C. Ornelas, kidney infection, Kidney stones, osteoarthritis, shingles
By Tina Donvito
Freelance writer covering health, culture, travel and parenting.
