Causes of hip pain

Among musculoskeletal disorders, hip conditions are not limited to old age. Hip pain is a common complaint that can be caused by many different problems. Precisely locating the hip pain can provide valuable clues to the underlying cause.

Problems within the hip joint itself usually result in pain felt deep in the hip or in the groin. Sharp pain on the outside of the hip, the upper thigh, or the outer buttock generally suggests issues with the muscles, ligaments, tendons, and other soft tissues surrounding the hip joint.

Sometimes disorders and conditions in other parts of the body, such as the lower back, can also be the cause. This type of pain is called referred pain.

Causes of hip pain

Hip pain can be caused by arthritis, injury, or other problems. The following list is not in order of frequency.

Inflammation (arthritis)

Psoriatic arthritis

A form of arthritis that affects some people with psoriasis. Psoriasis is a condition that causes red patches of skin covered with silvery scales. It results from cells building up rapidly on the skin surface, forming thick, silvery scales and itchy, dry, red patches that can sometimes be painful. In most people, psoriasis develops years before arthritis is diagnosed. In some, however, joint problems begin before or at the same time as the skin lesions.

Joint pain, stiffness, and swelling are the main signs and symptoms. These can affect any part of the body, including the fingertips and the spine, and range from relatively mild to severe. Both psoriasis and psoriatic arthritis can flare up and alternate with periods of remission.

There is no cure. Treatment aims to control symptoms and prevent joint damage. Without therapy, it can lead to disability.

Bursitis

Bursitis affects small, fluid-filled sacs called bursae that cushion the bones, tendons, and muscles near joints and reduce friction between moving parts of the body. Bursitis occurs when the bursae become inflamed.

Its most common locations are the shoulder, elbow, and hip. It can also occur at the knee, heel, and the base of the big toe. It often occurs near joints that perform frequent repetitive movements.

Treatment generally involves resting the affected joint and protecting it from further injury. In most cases, bursitis pain resolves within a few weeks with appropriate treatment, but recurrent flares are common.

Juvenile idiopathic arthritis

Previously called juvenile rheumatoid arthritis. It is the most common form of arthritis in children under 16 years of age.

Osteoarthritis and arthrosis

The most common form of arthritis, affecting millions of people worldwide. It develops when the protective cartilage that cushions the ends of the bones breaks down. It can affect any joint, but most commonly the joints of the hand, knee, hip, and spine.

Symptoms are generally manageable, though joint damage is not reversible. An active lifestyle (maintaining the strength of the muscles around the hip joint), maintaining a healthy weight, and certain treatments can slow the disease progression and help improve pain and joint function.

"Osteoarthritis" refers to joint inflammation, while "osteoarthrosis" denotes degeneration of the joint. Arthrosis can be a consequence of long-standing joint inflammation.

Rheumatoid arthritis

A chronic inflammatory disease that can affect not only the joints. In some people, the condition can damage many different body systems, including the skin, eyes, lungs, heart, and blood vessels.

It is an autoimmune disease in which your immune system mistakenly attacks your own body tissues.

Unlike the wear-and-tear damage of osteoarthritis, rheumatoid arthritis affects the lining of the joints, causing painful swelling that can eventually result in bone erosion and joint deformity. As the lining of the joints (synovium) becomes inflamed and thickened, fluid accumulates and the joints erode and break down.

The associated inflammation is what can damage other parts of the body. Although newer drugs have dramatically improved treatment options, severe disease can still cause physical disability.

Sacroiliitis

Inflammation of one or both sacroiliac joints, which connect the lower spine and pelvis.

The joint itself is between the sacrum — the bony structure above the tailbone and below the lower vertebrae — and the upper part of the pelvis (ilium). The sacroiliac joints are located on the right and left sides of the lower back. Strong ligaments hold these joints in place and support the full weight of your upper body when you stand. It can cause pain in the buttock or lower back and may extend down one or both legs. Prolonged standing or climbing stairs can worsen the pain.

It is difficult to diagnose because it can be mistaken for other causes of low back pain.

Treatment may include physiotherapy and medication.

Septic arthritis

A painful joint infection that may originate from bacteria in another part of the body that reach the joint through the bloodstream. It can also occur if an injury, such as an animal bite or trauma, directly introduces bacteria into the joint.

It is most likely to develop in infants and older adults. People with artificial joints are also at increased risk. The knee is most commonly affected, but the hip, shoulder, and other joints can also be involved. The infection can quickly and severely damage the cartilage and bone in the joint, so prompt treatment is essential.

Treatment involves draining the joint with a needle or surgery and administering antibiotics.

Synovitis

Synovitis is a mild inflammation of the synovial membrane of the hip joint of unknown cause (a small amount of fluid in the joint) that usually resolves on its own without residual damage.

It is the most common cause of hip pain in children. It affects about 2–3% of children aged 3 to 10. It occurs more frequently in boys.

Its main symptoms are hip pain and limping. Hip pain may radiate to the groin, the upper thigh, or sometimes to the knee, usually when it appears suddenly. It most commonly presents as a child limping after waking up or refusing to walk.

Treatment is based on rest, proportionate to the level of pain. Nonsteroidal anti-inflammatory drugs can reduce pain and inflammation. Synovitis typically resolves on average after 6–8 days.

Injuries

Hip fracture

A serious injury whose complications can be life-threatening. The risk increases with age.

The risk increases because bones weaken with age (osteoporosis). Multiple medications, poor vision, and balance problems also make falls more likely in older people, and falls are one of the most common causes of hip fractures.

It almost always requires surgical repair or hip replacement followed by physiotherapy. Measures to maintain bone density and avoid falls can help prevent hip fractures.

Labral tear

An injury affecting the ring of cartilage (labrum) that surrounds the outer edge of the hip joint socket. In addition to cushioning movements of the hip, the labrum acts as a sort of "rubber seal" and helps hold the femoral head (the top of the thigh bone) securely in the hip socket.

Athletes in sports such as ice hockey, soccer, golf, and ballet are at greater risk of labral tears. Structural problems of the hip can also cause them.

Tumor-related causes

Bone metastasis

Malignant tumors in advanced stages can form metastases (secondary tumors) in distant organs and/or bones.

Primary bone cancer

It can originate from any bone in the body but most commonly affects the pelvis or the long bones of the arms and legs. It is rare, accounting for less than 1 percent of all cancers. In fact, benign bone tumors are much more common than malignant ones.

The term "bone cancer" does not include cancers that start elsewhere in the body and spread to bone (metastasize). Those are named after their site of origin, for example breast cancer that has spread to bone.

Some types primarily occur in children, while others mainly affect adults. Surgical removal, chemotherapy, and radiotherapy are the usual treatments. Decisions about surgery, chemotherapy, or radiotherapy depend on the type of bone cancer being treated.

Other causes

Osteoporosis

As a result of osteoporosis, bones become weak and brittle — so much so that a fall or even mild stress, such as bending over or coughing, can cause a fracture. Osteoporotic fractures most commonly occur in the hip, wrist, or spine.

Bone is living tissue that is constantly being broken down and replaced. Osteoporosis occurs when the formation of new bone does not keep up with the loss of old bone.

Osteoporosis affects both men and women. The greatest risk is in older women who are past menopause. Medications, healthy nutrition, and regular exercise can help prevent bone loss or strengthen bones that are already weak. Pulsed electromagnetic field therapy (PEMF) is primarily used in the treatment of osteoporosis.

Sciatica

Pain that radiates along the path of the sciatic nerve (n. ischiadicus). This nerve runs from the lower back through the hip and buttock and down each leg. It usually affects only one side of the body.

It most often occurs when a herniated disc, a bone spur on a vertebra, or narrowing of the spinal canal compresses part of the nerve. This causes inflammation, pain, and often numbness in the affected leg.

Although the associated pain can be severe, in most cases it resolves in a few weeks with conservative treatment without surgery. Surgery may be needed for those with neurological signs of sciatica such as significant leg weakness or bowel and bladder control problems.

Legg-Calvé-Perthes disease

A childhood condition that occurs when the blood supply to the ball of the hip joint (femoral head) is temporarily disrupted and the bone begins to die. The hip joint is a ball-and-socket joint. The ball (femoral head) sits on top of the thigh bone (femur), and the socket (acetabulum) is part of the pelvic bone.

This weakened bone gradually breaks down and may lose its round shape. Over time the body eventually restores blood supply to the femoral head and it can heal, but if after healing the head is no longer round, it can cause pain and stiffness. The whole process of bone death, collapse, and renewal can take several years.

To help the ball of the joint remain as round as possible, doctors use various treatments to keep the head rounded within the socket during healing. The socket acts as a mold for the fractured femoral head as it heals.

Avascular necrosis

The death of bone tissue due to a lack of blood supply. Also called osteonecrosis, which can lead to tiny fractures in the bone and ultimately cause it to collapse.

A broken bone or a dislocated joint can interrupt the blood supply to a portion of the bone. Avascular necrosis has also been linked to long-term use of high-dose steroid medications and excessive alcohol consumption.

It can affect anyone, but the condition most commonly occurs in people in their 30s to 50s.