When one hip begins to hurt while walking, it can quickly turn a routine activity into a painful chore. This specific, one-sided pain is a common concern that suggests a localized issue with the mechanics of the joint or the surrounding tissue. The term “hip” itself is often used broadly, encompassing the deep ball-and-socket joint, stabilizing soft tissues, and external structures. Identifying the source of discomfort requires understanding the complex anatomy of this weight-bearing structure. Exploring potential causes, from internal joint damage to referred pain from the spine, helps clarify why one hip signals distress during movement.
Understanding Where Hip Pain Originates
The location of the pain is the most important clue for determining its origin. Hip pain can generally be classified into three distinct zones: anterior, lateral, and posterior. Pain felt deeply in the groin or the front of the hip (anterior) typically indicates a problem within the hip joint itself, such as damage to the cartilage or bone structure. Discomfort localized to the side of the hip, specifically over the greater trochanter (lateral), points toward issues with the surrounding soft tissues. Pain presenting in the buttock area (posterior hip) often signals a problem with the lower back, the sacroiliac joint, or the deep gluteal muscles.
Issues Inside the Hip Joint
Pain that is deep, aching, and centered in the groin often suggests an intra-articular problem. Osteoarthritis (OA) is a common culprit, involving the progressive breakdown of articular cartilage that cushions the joint surfaces. This breakdown causes bone-on-bone friction, leading to stiffness and pain that characteristically worsens with activity and improves with rest, especially in older adults.
A labral tear is another internal issue, involving damage to the ring of fibrocartilage that lines the hip socket and provides stability. This damage can cause sharp, stabbing pain, or a mechanical sensation like clicking or catching within the joint, particularly when twisting or flexing the hip.
Femoroacetabular impingement (FAI) involves abnormal bony growth on either the ball or the socket, leading to irregular contact and pinching of the joint structures during movement. FAI is a structural problem that can accelerate labral tears and often presents as groin pain when the hip is flexed, such as when getting in or out of a car.
Problems with External Tissues
When pain is felt on the outside of the hip, it usually relates to the surrounding muscles, tendons, or bursae. The most frequent cause of lateral hip pain is Greater Trochanteric Pain Syndrome (GTPS), which encompasses trochanteric bursitis and gluteal tendinopathy. Trochanteric bursitis is the inflammation of the bursa over the greater trochanter, causing sharp, localized pain that often makes it painful to lie on the affected side at night.
Gluteal tendinopathy, involving damage or overuse of the gluteus medius and minimus tendons, is a common component of GTPS. This generates a dull ache that can radiate down the side of the thigh and is aggravated significantly by activities involving standing on one leg, such as walking or climbing stairs.
Another soft tissue issue is hip flexor strain or tendinitis, presenting as pain high up in the groin. This involves the iliopsoas muscle and tendon, which are responsible for lifting the knee toward the chest. Repetitive movements, such as running or kicking, can lead to inflammation or a tear, and the pain is typically worsened by lifting the leg or when the muscle is stretched.
Pain Originating Outside the Hip
Not all hip pain originates in the hip; sometimes, the discomfort is referred from other body regions. Pain felt deep in the buttock or the back of the hip can signal a lower back problem, such as lumbar radiculopathy, commonly known as sciatica. This occurs when a nerve root in the lower spine is compressed or irritated, sending pain signals along the nerve pathway that are perceived in the hip and down the leg.
Sacroiliac (SI) joint dysfunction is another common source of referred pain. The SI joint connects the base of the spine to the pelvis. When this joint moves improperly, it causes pain deep in the buttock that may radiate to the hip or groin, often worsening with prolonged standing or sitting.
Furthermore, biomechanical issues, such as a leg length discrepancy or significant foot problems, can alter the body’s gait. This altered walking pattern places asymmetrical strain on one hip, overloading the muscles and tendons and eventually leading to pain perceived as a hip problem.
When to Seek Medical Attention
While many minor hip pains can be managed with rest, ice, and over-the-counter pain relievers, certain symptoms warrant a professional medical evaluation. Consult a healthcare provider if the pain is so severe that it prevents you from bearing weight on the leg or completing normal daily activities.
Urgent medical attention is required if pain is accompanied by signs of infection, such as fever, chills, or a hot, visibly swollen joint. If the pain persists or worsens after 7 to 10 days of self-care, or if you experience numbness, tingling, or weakness in the leg, a professional diagnosis is necessary. These persistent or neurological symptoms may indicate a more serious underlying condition, such as a spinal nerve issue or structural damage that requires targeted treatment.