Hip Joint

What is the hip joint?

A joint is a place in your body where two bones meet. Your hip joint is a connection point between your thigh bone (femur) and your hip bone (pelvis). Your hip joint is one of the largest joints in your body after your knee.

What type of joint is the hip?

Your hip joint is a ball-and-socket joint. Your femur is a long bone with a rounded top. The round part of your femur fits into a cup-like socket in your pelvis called the acetabulum. This type of joint offers a wide range of motion and provides support for your legs to hold your body.

How does the hip joint work?

Your hip joint connects your torso (axial skeleton) to your lower legs. The function of your hip joint is to:

• Provide balance and support for your upper body.
• Move your upper leg.
• Hold your body weight.

The ball-and-socket joint lets your upper leg move at 3 degrees so you can do the following movements:

• Flex.
• Extend.
• Rotate.
• A back-and-forth motion.
• A circular motion.

Where is my hip joint?

Your hip joint is where your thigh bone meets your hip bone. You have two hip joints, one at the top of each of your thigh bones. Your thigh bones are the top part of your legs (above your knees, just below your waist, where the top of your pants sit). The part of your thigh bone that’s closest to your waist fits into your hip bone (pelvis).

What does the hip joint look like?

Your hip joint is made up of your hip bone (pelvis) and your thigh bone (femur). Your femur is a long bone that has an angle near the top of the bone and points toward your pelvis. At the end of the thigh bone is the rounded end (femur head). This bone looks like a microphone in a stand.

The femur head rests inside a cup-like socket in your pelvis.

How big is my hip joint?

Your hip joint is one of the largest joints in your body. The top of your thigh bone (femur head) that fits into your hip bone (pelvis) is approximately 48 millimeters to 55 millimeters in diameter on the average person. This is about the same size as a small apple.

What is the hip joint made of?

There are several components that make up your hip joint:

• Bones: Your hip joint connects your thigh and hip bones.
• Cartilage: Cartilage is a smooth substance that covers the top of your thigh bone (femoral head) and the acetabulum socket. This substance is a cushion that absorbs impact when you walk and move.
• Synovium: The synovium is a thin cover that wraps around the bones in your joint. It makes a fluid that provides lubrication so your bones can move easily without resistance.
• Bursa: The bursa is a fluid-filled sac that provides cushioning and a smooth surface for the bones, muscles and tendons in your joints to move on.
• Ligaments: Ligaments are fibrous bands of tissue that connect bones to bones, specifically the femoral head to the acetabulum.
• Tendons: Tendons are fibrous bands of tissue that connect your muscles to your bones.
• Muscle: Your hips have large muscles that support your joint and help you move. Muscles in your hips include your gluteals, adductor muscles, iliopsoas muscle, quadriceps and hamstrings.

What are common conditions that affect the hip joint?

Your hip joints are usually very strong and stable. If you’re in good health, it could take a lot to injure your hip joints. If you play contact sports or run often, you may be more at risk of injuring your hip joint with:

• Hip strains: An injury or tear to your muscle tissue.
• Bursitis: Swelling of the fluid-filled sac in your joint.
• Hip dislocation: Your thigh bone pops out of the socket.
• Broken femur: An injury breaks or fractures one of the bones in your hip joint.

There are medical conditions that can weaken your hip joint. This can put you more at risk of injury or complications like pain or stiffness. Common conditions that affect your hip joint include:

• Osteoarthritis: Inflammation of your joints that causes pain and swelling.
• Osteoporosis: Bone weakness that may cause them to break easily.
• Hip dysplasia: Your thigh bone doesn’t fit together in your pelvis as expected.

What are common symptoms of hip joint conditions?

Common symptoms of hip joint conditions include:

• Pain.
• Swelling.
• Limited range of motion.

What tests check the health of my hip joint?

A healthcare provider may offer imaging tests to examine your hip joint. Imaging tests like a bone density test, an X-ray or an MRI help your provider see the components of your hip joint clearly. They can detect injuries like a broken bone or a tear to your muscle or ligament.

What are common treatments for the hip joint?

Treatment varies based on what’s affecting your hip joint. A healthcare provider will diagnose and offer treatment for your hip joint that could include:

• Rest and limiting physical activities.
• Taking medicines to reduce pain and swelling.
• Physical therapy to strengthen your muscles.
• Surgery to repair bones or other components of your hips.
• Hip replacement.

How do I keep my hip joint healthy?

You can take care of your hip joints by:

• Eating a well-balanced diet.
• Exercising regularly.
• Stretching before exercising.
• Wearing protective equipment to avoid injury.
• Maintaining a healthy weight that’s right for you and your body.

A note from Cleveland Clinic

Your hip joint is an important part of your body. It helps you walk and move while keeping your body balanced. You can keep your hip joints healthy by exercising and stretching your muscles before you start any activities. Try not to over-exert yourself past what your body can handle. A healthcare provider will let you know how you can take care of your hip joints.