Hip Anatomy: Understanding Your Hip's Structure

What is the anatomy of the hip?

The anatomy of the hip describes the bones and tissues that connect the pelvis to the thigh. This joint supports the body’s weight and allows the leg to move in several directions. Understanding its structures helps provide insight into certain types of hip pain and their treatment through physical therapy.

What are the main structures of the hip?

The main structures of the hip are the bones, cartilage, labrum, ligaments, muscles, and bursae. Together, these structures ensure the joint's movement and stability.

The Hip Bones

The hip joint, known as the coxofemoral joint, connects the head of the femur (the thigh bone) to the pelvis. The femoral head is spherical in shape and fits into the acetabulum (or hip socket), a cup-shaped cavity located in the hip bone of the pelvis¹.

The acetabulum is formed by the fusion of three distinct bones: the ilium, the ischium, and the pubis. This cup-shaped cavity houses the femoral head and helps maintain the stability of the joint while allowing it to move².

Cartilage and the Labrum

The articular surfaces of the femur and acetabulum are covered with articular cartilage, a smooth, durable tissue that allows the surfaces to glide against each other with minimal friction. The cartilage acts as a cushion that absorbs shock and distributes forces as you move.

The acetabular labrum is a ring of fibrous cartilage that lines the acetabulum. It deepens the joint cavity and stabilizes the femoral head, much like a seal. Labrum tears are found on imaging studies of people who have no pain: 27 of the 70 pain-free young adults in this study had a tear visible on magnetic resonance imaging, also known as an MRI. A tear visible on an MRI should therefore be interpreted in conjunction with your symptoms and physical examination, rather than automatically being considered the cause of your symptoms.³

The Stabilizing Ligaments

Three main ligaments reinforce the capsule, the lining of the hip joint:

The iliofemoral ligament (or Bigelow ligament) is the strongest ligament in the human body. Its inverted Y-shape limits two excessive movements: extension, when the leg moves backward, and external rotation, when the thigh turns outward¹.

The pubofemoral ligament is located at the front and limits excessive abduction (moving the leg too far out to the side).

The ischiofemoral ligament is located at the back and controls internal rotation—when the thigh rotates inward—as well as extension.

These three ligaments work together to keep the femoral head centered in the acetabulum while allowing for a wide range of motion—that is, the hip can move a long way in several directions.

The Hip Muscles

The gluteal muscles (gluteus maximus, medius, and minimus) are essential for hip stability and power. The gluteus maximus enables hip extension (when you stand up from a chair), while the gluteus medius stabilizes the pelvis when you shift your weight to one leg while walking.

The iliopsoas is the main hip flexor. It allows you to lift your thigh forward, a crucial movement for walking and climbing stairs.

The rotator muscles (piriformis, obturators, gemelli) control the fine rotations of the hip and contribute to the deep stability of the joint.

The Bursae

Bursae are small sacs filled with fluid that reduce friction between tendons, muscles, and bones. The trochanteric bursa is located on the side of the hip, near the greater trochanter, the bony protrusion of the femur. Inflammation of this bursa is called trochanteric bursitis. Pain in this area may also involve the gluteal tendons. In a study of 877 people with pain on the side of the hip, ultrasound revealed bursitis in about 20% and changes in the gluteal tendons in about 50%. These images complement the physical examination; they are not sufficient on their own to explain every case of pain. This study distinguishes between problems involving the bursa and those involving the tendons⁴.

How Does the Hip Work?

The hip joint allows the thigh to move thanks to a rounded bony head that pivots within a socket in the pelvis. This structure enables the leg to be bent, extended, and rotated. Ligaments and muscles stabilize the joint during these movements.

A Highly Mobile Ball-and-Socket Joint

The hip is a spheroidal joint, also known as an enarthrosis: the rounded head of the femur rotates within the acetabulum, a cavity in the pelvis. These movements can occur in combination, for example, when you get into a car².

Possible Movements

Flexion and Extension: You flex your hip when you lift your knee towards your chest (up to about 120 degrees). Extension brings your leg behind you (about 10 to 15 degrees).

Abduction and Adduction: Abduction moves your leg out to the side (about 45 degrees), while adduction brings it back towards the midline of your body and can even cross it slightly.

Internal and External Rotation: These movements turn your leg inward or outward. They are essential for changing direction when you walk or run.

Load Transmission

Your hip bears heavy loads with every step, and even more so when running or jumping. The spherical shape of the joint distributes these forces over a large surface area, which protects the cartilage and surrounding structures.

Stability Mechanisms

Hip stability relies on three elements: the depth of the acetabulum, which cups the femoral head; the strength of the capsular ligaments that hold the joint together; and the power of the muscles that control movement. When one of these elements weakens, pain can develop.

A hip problem doesn't always cause pain in the hip itself. Pain from the hip joint often radiates to the buttock, and sometimes to the groin or thigh.⁵

What are common hip injuries?

Common hip injuries include gluteal tendinopathy, trochanteric bursitis, femoroacetabular impingement,hip osteoarthritis, and labral tears.

Gluteal Tendinopathy

Gluteal tendinopathy affects the tendons of the gluteal muscles, particularly the gluteus medius. This condition causes pain on the side of the hip, which is often worsened by climbing stairs.

Trochanteric Bursitis

Trochanteric bursitis refers to inflammation of a bursa on the side of the hip. The broader term “greater trochanter pain syndrome” encompasses pain in this region, including pain in the gluteal tendons. The bursa and the tendons may be affected together. Possible symptoms include tenderness and pain when lying on the affected side. For confirmed gluteal tendinopathy, physical therapy may combine exercises with advice on adjusting daily activities. In a trial involving 204 people, 51 out of 66 reported improvement after eight weeks of this program, compared with 38 out of 65 after a cortisone injection and 20 out of 68 in the wait-and-see group⁶.

Femoroacetabular Impingement

Femoroacetabular impingement refers to painful contact between the femur and the rim of the hip socket during certain movements. Diagnosis is based on a combination of symptoms, clinical examination, and imaging. An abnormality in bone shape visible on imaging alone is not sufficient: some people have these abnormalities without experiencing pain. The Warwick International Consensus clarifies this distinction⁷.

Femoroacetabular impingement can be treated with a tailored exercise program and guidance, or with surgery in some cases. A previous review noted that there were still few trials on non-surgical treatment⁸. A subsequent trial involving 348 participants observed improvements in both the personalized physical therapy group and the surgery group, with an average benefit favoring surgery after one year. The choice depends largely on your symptoms, your goals, and the risks associated with each option. The UK FASHIoN trial describes these results⁹.

Hip Osteoarthritis

Hip osteoarthritis involves changes in the cartilage that become more common with age, much like wrinkles or gray hair. These changes do not always cause pain: there are both painful and painless forms of osteoarthritis. Possible symptoms include deep pain in the groin, morning stiffness, and a gradual decrease in range of motion. Physical therapy cannot reverse these changes, but it can help turn painful osteoarthritis into a pain-free condition and preserve your ability to walk and perform your daily activities.

In a study of 978 residents of Framingham, in the United States, aged 50 and older, the estimates took age into account: about one in five people had hip osteoarthritis on X-ray, and about one in twenty-five also had pain in that hip.¹⁰

Labral Tear

The acetabular labrum can tear as a result of trauma or repetitive movements. Typical symptoms include a sensation of locking or catching in the hip, accompanied by deep pain in the groin. Treatment depends on your symptoms, limitations in your activities, and the results of your examination. It may include physical therapy and, in some cases, surgery.

How Does Physiotherapy Help Hip Problems?

Physical therapy helps reduce hip pain and restore mobility, strength, and the ability to perform daily activities. The physical therapist combines exercises, manual techniques, and advice based on your assessment. He or she can also work on the walking movements that are causing you problems.

The Complete Assessment

Your physiotherapist begins with a detailed assessment of your hip. This assessment includes:

• Observing your gait and your daily movements
• Measuring hip movement to see how far it can move
• Assessing the strength of different muscle groups
• Targeted tests to identify tissues that may contribute to pain
• Observing your posture and how your back, pelvis, and legs move together

The evaluation helps link your symptoms to your hip’s range of motion and function. The results are used to develop a personalized plan. A single test or image isn’t always enough to explain the pain; the physical therapist takes your entire situation into account.

Hip osteoarthritis can limit mobility, particularly internal rotation. This is one of the signs a physical therapist looks for during an examination.¹¹

Treatment Approaches

Physiotherapy for hip pain uses several complementary approaches:

Strength-training exercises target weakened muscles, particularly the glutes and deep rotator muscles. Strength training prepares your muscles for the demands of your activities.

Mobility exercises help improve the hip movements you need for your activities. Your physical therapist will teach you appropriate stretches and help you progress at your own pace.

Manual therapy may include massage and mobilization—joint movements guided by the physical therapist’s hands. The physical therapist selects these techniques based on your pain and range of motion, in addition to exercises and advice. For mild to moderate hip osteoarthritis, recent recommendations include manual therapy to improve pain and movement. The summary of the 2025 guideline on hip osteoarthritis describes this approach¹².

Gait rehabilitation focuses on the movements that are causing you problems. The physical therapist can adjust your stride length, walking pace, or use of a walking aid based on your needs. These changes are intended to make your daily activities easier; they do not guarantee that you will not have a relapse.

Pain education and management give you the tools you need to understand your condition and manage your symptoms on a daily basis.

Expected results

Hip problems can improve with appropriate physical therapy. Home exercises are part of the treatment and are tailored to what you are able to do. With appropriate treatment and your active participation, you can expect:

• For lateral hip pain associated with gluteal tendinopathy, improvement was measured after an eight-week program: the average pain score was 1.5 out of 10 in the group that received education and exercises, compared with 3.8 out of 10 in the wait-and-see group.⁶
• Progressive improvement in your mobility and strength
• A gradual return to your daily and sports activities
• Strategies to prevent long-term recurrence

FAQ about Hip Anatomy

Frequently asked questions about the hip include nighttime pain, connections to the back, osteoarthritis, sports, recovery, and injury prevention. The hip may hurt on the side, in the groin, or near the buttock, and treatment depends on the structures and activities involved. The following answers explain the connections to sleep, the back, sports, and recovery.

Why does my hip hurt when I sleep on my side?

This nighttime pain on the side of the hip often suggests trochanteric bursitis or gluteal tendinopathy. Direct pressure on the affected areas causes discomfort. A physical therapist can help you with strengthening exercises and positioning tips.

Are my hips related to my lower back pain?

The hip and lower back move together during walking, bending, and when transitioning from a sitting to a standing position. Pain felt around the hip may require an examination of both areas. A small study of 51 people with pain originating in the hip joint primarily observed pain in the buttocks, groin, and thigh, and none in the lower back. This result does not prove that reduced hip mobility causes lower back pain⁵.

At what age does hip osteoarthritis begin?

Hip osteoarthritis becomes more common with age, particularly after age 50. Factors such as joint deformities, previous injuries, or being overweight can accelerate its progression. Physical therapy can help you even in the early stages.

In patients presenting at primary care with hip or groin pain, a combination of clinical signs can identify those most likely to have severe osteoarthritis.¹¹

Can I continue to play sports with hip pain?

Hip pain doesn’t always mean you have to stop exercising. A physical therapist can adjust the duration, intensity, or movements based on your symptoms. However, severe pain after a fall or an inability to walk or put weight on your leg requires an evaluation in the emergency room. A warm, swollen hip also requires urgent medical attention, even without a fever. Hip pain accompanied by a fever and general malaise also requires urgent medical attention. These signs require prompt care¹³.

How long does it take to heal a hip problem?

The recovery time depends on the hip problem and the activities the patient hopes to resume. For persistent gluteal tendinopathy, one study observed improvements after eight weeks of exercises and guidance, though this did not mean a complete recovery for everyone⁶. For femoroacetabular impingement, one study program lasted 12 to 26 weeks. The physical therapist monitors your progress and adjusts the duration based on your response. This personalized physical therapy program provides a guideline, not a deadline for recovery¹⁴.

How can I prevent hip injuries?

Prevention relies on several factors: maintaining good strength in the gluteal and rotator muscles, preserving adequate hip mobility, avoiding sudden increases in physical activity, and working with your physical therapist to identify which movements your hip currently has difficulty with, then gradually working on them. Your physical therapist can assess your risk factors and create a personalized prevention program.

References

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2. Kenhub. Hip and Thigh Anatomy. ↩ Back to text: 1st, 2nd mentions
3. Lee AJ, Armour P, Thind D, Coates MH, Kang AC. The prevalence of acetabular labral tears and associated pathology in a young, asymptomatic population. Bone Joint J. 2015;97-B(5):623-7. ↩ Back to text
4. Long SS, Surrey DE, Nazarian LN. Sonography of greater trochanteric pain syndrome and the rarity of primary bursitis. AJR Am J Roentgenol. 2013;201(5):1083-6. ↩ Back to text
5. Lesher JM, Dreyfuss P, Hager N, Kaplan M, Furman M. Hip joint pain referral patterns: a descriptive study. Pain Med. 2008;9(1):22-5. ↩ Back to text: 1st, 2nd citations
6. Mellor R, Bennell K, Grimaldi A, Nicolson P, Kasza J, Hodges P, et al. Education plus exercise versus corticosteroid injections versus a “wait-and-see” approach on global outcome and pain from gluteal tendinopathy: a prospective, single-blinded, randomized clinical trial. BMJ. 2018;361:k1662. ↩ Back to text: 1st, 2nd, 3rd citations
7. Griffin DR, Dickenson EJ, O’Donnell J, Agricola R, Awan T, Beck M, et al. The Warwick Agreement on femoroacetabular impingement syndrome (FAI syndrome): an international consensus statement. Br J Sports Med. 2016;50(19):1169-76. ↩ Back to text
8. Wall PD, Fernandez M, Griffin DR, Foster NE. Nonoperative treatment for femoroacetabular impingement: a systematic review of the literature. PM R. 2013;5(5):418-26. ↩ Back to text
9. Griffin DR, Dickenson EJ, Wall PDH, Achana F, Donovan JL, Griffin J, et al. Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicenter randomized controlled trial. Lancet. 2018;391(10136):2225-2235. ↩ Back to text
10. Kim C, Linsenmeyer KD, Vlad SC, Guermazi A, Clancy MM, Niu J, et al. Prevalence of radiographic and symptomatic hip osteoarthritis in an urban U.S. community: the Framingham Osteoarthritis Study. Arthritis Rheumatol. 2014;66(11):3013-7. ↩ Back to text
11. Metcalfe D, Perry DC, Claireaux HA, Simel DL, Zogg CK, Costa ML. Does This Patient Have Hip Osteoarthritis?: A Systematic Review of the Rational Clinical Examination. JAMA. 2019;322(23):2323-2333. ↩ Back to text: 1st, 2nd citations
12. Hip Pain and Mobility Deficits - Hip Osteoarthritis: 2025 Revision. Using the Evidence to Guide Musculoskeletal Rehabilitation Practice. J Orthop Sports Phys Ther. 2025;55(12):1-2. doi:10.2519/jospt.2025.0504 ↩ Back to text
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14. Wall PD, Dickenson EJ, Robinson D, Hughes I, Realpe A, Hobson R, et al. Personalized Hip Therapy: Development of a Non-Surgical Protocol to Treat Femoroacetabular Impingement Syndrome in the FASHIoN Randomized Controlled Trial. Br J Sports Med. 2016;50(19):1217-23. ↩ Back to text

Our physical therapists defined the research strategy, plan, and clinical content of this article. An AI tool assisted with the literature review and text editing to ensure consistency in content and writing style.