A urinary tract infection (UTI) is a common bacterial infection that most often involves the bladder and urethra. While UTIs are known for causing discomfort during urination, the body’s complex network of nerves means an infection localized in the bladder can sometimes cause pain in unexpected areas. Aching or soreness in the hip region can be connected to an underlying urinary tract infection, though this sensation is often an indirect result.
How Urinary Tract Infections Cause Referred Pain
The pain felt in the hips, groin, or lower abdomen due to a UTI is a phenomenon known as referred pain. This occurs because internal organs and the skin or muscles share common nerve pathways that travel to the spinal cord. When the bladder becomes inflamed due to a bacterial infection, the brain receives strong pain signals from the visceral nerves supplying the pelvis. These visceral pain signals can be misinterpreted by the central nervous system as originating from a different, nearby area, such as the hips or lower back.
The inflammation within the pelvis can also cause the surrounding muscles to become tight and restricted, a condition known as pelvic floor dysfunction. These pelvic floor muscles have attachments to the hip bones, and their tension can directly contribute to hip and groin discomfort. The resulting pain is typically diffuse, meaning it is a generalized ache across the lower body rather than being sharply localized.
Classic Symptoms That Confirm a UTI
Since hip pain is an atypical presentation, it is important to check for the definitive, classic signs of an uncomplicated UTI. The most common symptom is dysuria, characterized by a painful or burning sensation during urination. This discomfort results from the irritation and inflammation of the urethra and bladder lining caused by the bacteria.
A person with a UTI will experience a pronounced change in urinary habits, including a frequent or sudden, intense urge to urinate (urgency). This persistent need often produces only small amounts of urine at a time. The urine itself can also appear cloudy or have a noticeably strong, foul odor.
The infection may also cause a feeling of pressure or mild pain in the suprapubic area, located just above the pubic bone. Identifying these direct signs alongside any hip discomfort helps confirm that the urinary tract is the likely source of the overall symptoms. These lower tract infections (cystitis) require treatment to prevent further progression.
Recognizing the Signs of a Complicated Infection
When an infection spreads from the lower urinary tract up to one or both kidneys, it is termed pyelonephritis, a complicated and potentially serious condition. The pain associated with a kidney infection is intensely localized to the flank—the area on the side of the body between the ribs and the hip—or the upper back. This deeper, more severe pain is commonly misinterpreted as originating from the hip joint or lower back muscles.
Unlike the referred pain from a simple bladder infection, kidney pain is generally situated higher up, often felt beneath the rib cage, and may radiate forward toward the abdomen or groin. Pyelonephritis is further distinguished by systemic symptoms that indicate the infection is affecting the entire body. These symptoms include a high fever, shaking chills, and a general feeling of being unwell.
Digestive distress is also a common indicator, presenting as nausea and vomiting, which can lead to extreme fatigue. If hip or back pain is accompanied by any of these systemic signs, it signals a medical situation that requires immediate evaluation and treatment. Untreated pyelonephritis can lead to lasting kidney damage or a bloodstream infection.