Joint Replacements and Imaging in Ajax: X-Rays After Surgery

Before we get into the why, here is the short version for anyone heading out the door with a requisition for an X-ray of a replaced joint:

• Bring your health card and the requisition from your surgeon or family doctor.
• Tell the technologist which joint was replaced, roughly when, and on which side.
• Wear clothing without metal near the area, or be ready to change into a gown.
• If you have earlier images on a CD from another hospital or clinic, bring them along or ask how they can be shared with your surgeon.
• Use your usual walking aid, and allow a little extra time to get on and off the X-ray table.

That covers the practical part. The rest of this article is about the reasons behind those images: what a surgeon is looking for on an X-ray of a new hip, knee or shoulder, why the same joint may be imaged several times over the years, and which symptoms should send you for care rather than wait for your next scheduled picture. It is written for people across Ajax, Pickering and Whitby living with a joint replacement, and for family members who help them get to appointments.

A replacement is a partnership between metal, plastic and bone

A joint replacement swaps worn joint surfaces for artificial parts. Depending on the joint and the design, those parts may be made of metal, a durable plastic, ceramic, or a combination. Some are fixed in place with a type of bone cement; others are designed so the bone grows into a textured surface over time.

Either way, the long-term success of the joint depends on the relationship between the implant and the living bone around it. The implant does not change much. The bone does. It remodels, responds to load, and, as we age, can become thinner. Follow-up imaging is largely about watching that relationship.

Why X-ray is the workhorse for implants

X-rays show dense materials clearly. Metal components appear as bright, sharply outlined shapes, and the bone around them is visible in fine detail. That makes plain X-ray well suited to answering the main questions surgeons ask about a replaced joint.

Other types of imaging have a harder time with metal. Ultrasound, for example, can be useful for soft tissues around a joint, but sound waves cannot see through an implant, and the metal can create artifacts that interfere with the picture. If you want a broader comparison of what each test shows, our article on ultrasound versus X-ray explains the general differences.

Having an implant does not prevent you from having an ordinary X-ray. The technologist simply needs to know it is there so the right views can be taken.

What a surgeon looks for on follow-up images

A follow-up X-ray of a replaced joint is not just a quick look to see that the parts are still there. Your surgeon and the radiologist reading the images pay attention to several specific features.

Position and alignment

The angle and placement of each component matter for how the joint moves and how load passes through it. The first images after surgery show how the parts were positioned. Later images confirm that nothing has shifted.

The interface between implant and bone

The thin zone where implant meets bone, or where cement meets bone, is examined closely. A thin, stable line can be normal. A line that widens over time may prompt a closer look, because it can be one sign that a component is becoming loose.

Bone quality around the implant

Radiologists look at the density and shape of the bone surrounding the implant. Changes in the bone, such as areas that look thinner, can be worth monitoring.

Wear

In some designs, a plastic liner sits between two harder surfaces. Plastic does not show up brightly on an X-ray, but the space it occupies does. If the gap between the metal parts gradually narrows or becomes uneven, that can suggest the liner is wearing.

Anything new

After a fall or a new episode of pain, the question becomes whether there is a fracture near the implant, a dislocation, or another change that was not there before.

Comparison is what makes the images useful

A single X-ray of a replaced joint tells part of the story. A series tells much more. Many of the features above, such as a line around a component or the height of a liner space, are judged by whether they have changed since the last image.

That is why your surgeon’s office may ask you to have images taken at particular intervals, and why they care about having the earlier ones available. Schedules differ from surgeon to surgeon and patient to patient, so follow the plan you have been given rather than any general rule.

If your surgery took place at a hospital some distance from home, it can be easier to have follow-up X-rays taken closer to where you live in Ajax and have the images sent to your surgeon. Ask your surgeon’s office how they prefer to receive them. Our clinic can provide images on CD when needed, and our article on getting copies of your imaging on CD explains how that works.

Before your appointment: a few points worth knowing

Our clinic offers walk-in digital X-ray. Walk-in capacity changes through the day and the X-ray service may close once the day’s capacity has been reached, so it is a good idea to call 905-426-3111 for live availability before you set out. If you are unsure whether your particular X-ray needs a requisition, or whether it should be booked rather than walked in, call the clinic to confirm.

Our walk-in X-ray guide covers the visit itself in detail. A few points are specific to people with a replaced joint:

1. Mention every implant. If you have more than one replacement, plates, screws or other hardware, say so. It helps the technologist plan the views.
2. Expect more than one view. Joints are usually imaged from at least two angles. Some requisitions ask for images taken while standing, particularly for knees, so be ready for that and ask for help if you need it.
3. Move at your own pace. Getting onto the table or holding a position can be harder in the weeks after surgery or if other joints are sore. The technologist can help with positioning. Tell them about any movements your surgeon has asked you to avoid.
4. Bring your walking aid. Use your cane, walker or crutches as usual. Free parking and ground-floor access at our clinic make arrival simpler.

Life with a replaced joint: when imaging is about something else

Over the years, people with joint replacements may be sent for imaging that is not about the implant at all. A new ache in the other knee, back pain, or a fall onto a wrist all bring their own questions. It is still helpful to tell the technologist about your implants each time.

Bone health deserves a mention here. Many people who have joints replaced are of an age when bone density is also something providers think about. If your provider is concerned about osteoporosis, they may refer you for a bone mineral density scan, which is a separate low-energy X-ray test that requires a referral. Some implants or hardware can affect where that scan is taken, so mention them when you book.

Symptoms that should not wait for a scheduled X-ray

Planned follow-up images are for monitoring. Some symptoms need prompt attention instead:

• After a fall, severe pain in the replaced joint, a leg that looks shortened or turned, or being unable to put weight on the leg. Go to an emergency department or call 911.
• Signs of possible infection, such as increasing redness, warmth or swelling around the joint or incision, drainage from the wound, fever or chills. Contact your surgeon’s office or health-care provider urgently, and go to an emergency department if you cannot reach them or feel very unwell.
• Calf pain or swelling, especially in the weeks after surgery. This can be a sign of a blood clot and needs prompt assessment. Our article on DVT ultrasound explains how clots in the leg are checked.
• Chest pain or sudden shortness of breath. Call 911 right away.
• A joint that suddenly gives way, clunks or locks with new pain. Contact your surgeon’s office promptly for advice.

What the results mean for you

The radiologist’s report goes to the provider who ordered the X-ray. Your surgeon or family doctor then compares it with your symptoms, your examination and your earlier images. A finding described on a report is not automatically a problem, and an X-ray that looks stable is reassuring but does not replace the conversation about how the joint is actually working for you day to day. If you have questions about your results, ask the provider who ordered the test.

Follow-up X-rays close to home

Rossland Diagnostic Clinic is at Unit 102, 300 Rossland Road East in Ajax, open Monday to Friday from 9:00am to 5:00pm and Saturday from 8:00am to 3:30pm. If your surgeon has asked for a follow-up X-ray of a replaced hip, knee or shoulder, call 905-426-3111 to check walk-in availability, or request an appointment for a time that suits you.