What is a Hip X-Ray and What Can It Diagnose?
An x-ray is a type of medical imaging test used to help doctors diagnose various health conditions, including bone fractures and bone abnormalities. They can also be used to detect conditions affecting the organs and soft tissues. X-rays are a safe, painless and quick way of capturing an image (called a radiograph) of the inside of most parts of the body, that can then be used to help determine the best course of treatment if necessary.
Hip x-rays can be very useful in diagnosing problems affecting the hip joints and bones of the pelvis.
What is a Hip X-Ray?
A hip x-ray is a type of x-ray that focuses on the hip area - the area low down in your abdomen that covers the hip joints, pelvis and top of the thigh bone (femur). Usually used to detect problems affecting the bones and joints, x-rays can also be used to diagnose a condition within the soft tissues and organs. A hip x-ray is commonly used to find the causes of hip pain and problems with movement and mobility stemming from the hips and upper legs.
X-rays use electromagnetic waves to create low doses of radiation that’s passed through the part of the body being scanned. These waves cannot be felt as they pass through the body, and they cannot be seen by the naked eye.
Who Performs a Hip X-Ray?
Hip x-rays are usually performed by a trained medical specialist called a radiographer. The images are then sent to a doctor called a radiologist for interpretation and diagnosis.
What a Hip X-Ray Can Diagnose
A hip x-ray is capable of diagnosing a wide range of medical conditions affecting the bones and soft tissues of the hip joint.
Fractures
A bone fracture is a crack or a break in a bone. The top of the thigh bone (femur) is connected to the pelvis within the hip joint. The femoral neck is the part of the femur that connects the top, or head, of the femur to its long shaft, and is prone to fractures, especially in the elderly.
Dislocations
A dislocated hip occurs when the top of the femur (the “ball”) pops out of the cup-shaped socket of the hip bone.
Arthritis
A lining of cartilage cushions the area between the top of the femur and the pelvic bones within the hip socket. Arthritis causes this cushioning to wear away, causing pain and movement issues.
Hip Dysplasia
Hip dysplasia, where the socket of the hip joint doesn’t fully cover the ball, or the top of the femur, can lead to hip dislocations. It’s normally diagnosed in babies and young children.
Osteoarthritis
Osteoarthritis is a type of arthritis caused by general wear and tear and getting older.
Labral Tears
A labral tear is a tear in the cartilage that cushions the hip joint and is often caused by overuse such as long distance running or a sports injury.
Bone Infections
Infections caused by bacteria, viruses or fungi can develop and spread to the bones of the hip in a painful condition called osteomyelitis.
Tumours
Tumours can develop in the bones, that can be cancerous and non-cancerous, that can lead to pain and discomfort in the hip.
Avascular Necrosis
Often as a result of injury or as a complication of a hip fracture, avascular necrosis occurs when the blood supply to the hip joint is cut off or disrupted, causing pain, stiffness and immobility.
Congenital Hip Abnormalities
Congenital, meaning “born with”, hip abnormalities mean that a baby’s hip joint hasn’t developed properly, often leading to hip dysplasia.
Femoroacetabular Impingement
Femoroacetabular, or hip, Impingement occurs when the bones of the hip joint are misshapen usually through injury or from birth, leading to pain, stiffness and limping as the bones rub together.
Hip Impingement Syndrome
Hip impingement syndrome is another name for femoroacetabular impingement (see above).
Bursitis
The bursa are fluid-filled sacs that cushion the joints, including the hip. Bursitis is caused when the bursa become inflamed, normally through repetitive movement during sports or a sudden injury, leading to pain, swelling and movement issues.
Tendonitis
Tendonitis is similar to bursitis (see above), but it affects the tendons (the soft tissue that connects muscles to bones) within the hip causing pain and stiffness.
Bone Spurs
Bone spurs are abnormal bony growths that can change the shape of the bone, causing pain and discomfort. They’re often associated with the early stages of arthritis in the hip.
Types of Hip X-Rays
There are two types of hip x-ray; standard and specialised. Which type is taken will depend on your symptoms.
Standard Hip X-Rays
Most hip x-rays will be taken from above while you assume two standard positions:
Anteroposterior (AP) View
Laying on your back with your legs out straight.
Lateral View (Frog-Leg)
Laying on your back with your hips open, feet together and your knees apart.
Specialised Hip X-Rays
More specialised hip x-rays are taken from various other angles while your radiologist helps you assume different positions:
Cross-Table Lateral View
Laying on your back with your unaffected hip in the standard anteroposterior position, and your affected hip internally rotated by 15-20 degrees. The x-ray is positioned parallel to the table and the beam directed at a 45 degree angle to the hip.
Dunn View
Laying on your back with your legs lifted up, your hips at 90 degrees and your knees bent. The x-ray beam is directed towards the middle of your hip area, through your legs, towards your bottom.
Judet View
Laying on your back with the affected hip rotated 45 degrees and the x-ray beam directed towards the hip from above.
False Profile View
Standing with your back against a digital recording plate (see below under X-Ray Equipment) and the x-ray beam directed at the top of the femur on the affected side.
How an X-Ray Works
X-rays use low doses of radiation passed painlessly through the body to create images. Radiation creates energy, and as the x-rays pass through the body, this energy is absorbed differently by different types of tissue. A special x-ray detector within the x-ray machine then picks up these differences in energy absorption.
It’s difficult for x-ray energy to pass through hard, dense tissues such as bone, and as a result, these tissues create a white image on an x-ray. Softer tissues, such as tendons, ligaments, muscles and organs, as well as tumours and abnormal growths, can absorb x-rays more readily, and as such, appear darker, as different shades of grey or black on an x-ray.
Trained radiologists are able to see abnormalities in the hard and soft tissues, helping them to diagnose health conditions and put treatment plans in place. X-rays are often used in conjunction with other tests and scans including blood tests, CT and MRI scans, and other medical professionals such as orthopaedic consultants and surgeons that specialise in bone health and correcting bone breaks and abnormalities.
Benefits
X-rays are effective, quick, relatively safe and painless, and don’t require much, if any, special preparation. They only very rarely cause side effects and these are often outweighed by the benefits of a diagnosis and treatment plan as a result of having an x-ray.
Risks & Side Effects
Radiation doesn’t come without risks, although the level of radiation used in one x-ray is very low and only lasts for a fraction of a second. The natural environment contains natural radiation and the levels from one x-ray are estimated to be roughly the same as the natural exposure from spending between a few days and a few years in the environment, depending on the environment.
However, having multiple x-rays will mean multiple exposures to radiation. There is evidence to suggest that radiation exposure from x-rays could lead to certain cancers many years later, but this small risk is outweighed by the benefits of having an x-ray to get a diagnosis and treatment.
It’s recommended that pregnant women and very young children avoid having an x-ray unless it’s a medical emergency, and the benefits outweigh the risks.
How to Prepare for a Hip X-Ray
Hip x-rays don’t require much preparation. It can be helpful to arrive at your appointment wearing loose fitting clothing that’s easy to remove. Avoid wearing clothing with metal zips, buttons or embellishment. You may need to remove your lower clothing and wear a hospital gown. Sometimes it may be possible to carry out the x-ray with your lower clothing pulled down.
You will be asked to leave your belongings in a secure locker in a separate room - no mobile phones, keys, coins, jewelry, belts or other metallic objects will be allowed in the x-ray machine as they will show on the x-ray.
You can eat and drink and take medications as normal before a hip x-ray, unless told otherwise by your medical team. It may be more comfortable for you to pass urine before your scan as you may be lying down for a while.
The Procedure Explained: What to Expect
A hip x-ray takes place over a number of stages, and the whole process takes around 20 minutes.
Positioning on X-Ray Table
When you arrive, you will be asked to lay on a table on your back. You will be required to lay still for several images to be taken, and you may be asked to hold your breath for a few seconds while the image is taken.
Centering the X-Ray Beam
Your radiographer will be in the same room as you, but they will control the machine from behind a lead-lined screen to minimise their radiation exposure. They will move the x-ray machine remotely to ensure the x-ray beam is correctly angled towards your hip area.
Taking the Anteroposterior (AP) View
Images will be taken of your hip area while you’re in the anteroposterior position - laying flat on your back with your legs straight out.
Taking the Lateral View (Frog-Leg)
Your radiographer will then help you into the lateral view, or frog-leg position - on your back with your feet together and knees apart, before returning to behind the screen to take further images.
Other Specialised Views
If required, and depending on your symptoms, you may be helped into further positions such as with a rotated hip or in a standing position for more specialised x-ray images.
Image Processing and Review
X-ray machines create a number of black and white images. The clearest and most useful are collated and linked to your patient record, before being sent to a specialist for review.
Radiologist Interpretation
The images taken during a hip x-ray are sent to a specialist called a radiologist who will then use their knowledge and expertise to diagnose or rule out a condition that could be causing hip pain or mobility and movement problems.
X-Ray Equipment
An x-ray machine is a large machine with a large light attached to it, usually suspended from the ceiling. A bed is positioned underneath the machine. This bed is lined with a digital recording plate that you will need to lay on, and will record the images and send them to a computer.
What Happens After a Hip X-Ray?
After a hip x-ray, your radiologist will ask you to get dressed and meet them in a room separate from the x-ray machine. They will explain how long you may have to wait for your results. It’s not common to be given a diagnosis at the same time as a hip x-ray - it may be later the same day or some days later.
Getting the Results
Results from a hip x-ray are usually given by your referring doctor who would’ve been given them by a radiologist. They may also ask for an opinion by another doctor or consultant who specialises in specific medical conditions, such as an orthopaedic surgeon, before giving you your results.
Costs
In the UK, a private hip x-ray usually costs between £150 and £200.
Get a Hip X-Ray
If you’re concerned about hip pain or movement problems that you think may stem from your hip or hips, book a private hip x-ray with us today. The sooner you can have a condition diagnosed, the sooner you can start treatment and begin living your life pain-free.
FAQs
What Do You Wear for a Hip X-Ray?
Wear loose clothing that’s easy to remove and avoid wearing anything with metal zips, buttons, embellishments or buckles as these will show on the x-ray. You may be asked to undress and wear a medical gown.
How Long Does a Hip X-Ray Take?
A hip x-ray usually takes no longer than 20 minutes from start to finish.
Will an X-Ray Show If I Need a Hip Replacement?
Yes, if you have a condition that’s causing severe pain and restriction of movement, an x-ray is often one of the first tests a doctor will perform in order to determine if a hip replacement is right for you.
Can a Hip X-Ray Show Cancer?
Yes, an x-ray can show tumours in the bones or soft tissues of the hip, and x-rays are often used alongside blood tests and other scans such as an MRI or CT scan to diagnose cancer.
What Does Arthritis Look Like on a Hip X-Ray?
Arthritis causes the degradation of the cartilage that cushions the space between the top of the femur and the hip socket and this shows as a narrowing of the space on an x-ray.
References
Professional, C. C. M. (2024c, December 19). Hip X-Ray. Cleveland Clinic. https://my.clevelandclinic.org/health/diagnostics/23508-hip-x-ray
Website, N. (2022a, May 4). X-Ray. nhs.uk. https://www.nhs.uk/conditions/x-ray/
Krans, B. (2017, July 9). X-Ray of the pelvis. Healthline. https://www.healthline.com/health/pelvis-x-ray
Clohisy, J. C., Carlisle, J. C., Beaulé, P. E., Kim, Y. J., Trousdale, R. T., Sierra, R. J., Leunig, M., Schoenecker, P. L., & Millis, M. B. (2008). A systematic approach to the plain radiographic evaluation of the young adult hip. The Journal of bone and joint surgery. American volume, 90 Suppl 4(Suppl 4), 47–66. https://doi.org/10.2106/JBJS.H.00756