Knee X-ray views: a clinical reference pageWhen does knee pain need an X-ray, and which views?

The short answer

Request a knee X-ray when the answer will change what happens next: to exclude a fracture after an injury, or to plan treatment for a knee that is wearing. Every knee X-ray Orwyn writes is weight-bearing: an AP and a lateral, with a skyline view of the kneecap. Where osteoarthritis or malalignment is suspected, a long-leg standing view of both legs and a Rosenberg view are added.

Reviewed by Dr Arj Imbuldeniya, consultant orthopaedic knee and hip surgeon. Last reviewed 21 September 2026.

Who this is for

Written for the clinician seeing the patient first

This page is written for first contact practitioners, advanced practice physiotherapists, MSK physiotherapists and GPs. It is not advice for patients, and it does not replace local pathways or the clinician’s own judgement. Where a statement is Dr Imbuldeniya’s own clinical position rather than published guidance, it says so.

After an injury

Excluding a fracture

The Ottawa Knee Rule identifies the injured knee that needs an X-ray: age 55 or over; tenderness at the head of the fibula; isolated tenderness of the patella; inability to bend the knee to 90 degrees; or inability to take four steps both immediately after the injury and when assessed. Its implementation study is listed under the sources below.

Orwyn asks about weight-bearing at the assessment only. That makes it deliberately broader than the validated rule: it catches every case the rule would catch, and some it would not. Dr Imbuldeniya ruled this on 20 September 2026, because a second question on every injury adds time for no safety gain.

The request reads: AP and lateral of the knee, weight-bearing where the patient can stand, with a skyline view where the patella is tender, and the reason, that a fracture must be excluded after this injury. Where the patient cannot stand, the lateral is taken as a horizontal-beam lateral, which shows fat and blood in the joint.

After the X-ray there are two routes. A fracture, or fat and blood in the joint: refer the same day to the on-call orthopaedic team. No fracture: complete the assessment the same day.

The standard set

AP, lateral and skyline, all weight-bearing

Every knee that needs an X-ray gets three views: a weight-bearing AP, a lateral and a skyline view of the patellofemoral joint. In Dr Imbuldeniya’s opinion the skyline is the most important of the three, because it shows the joint behind the kneecap.

A wearing knee

Weight-bearing X-rays for every suspected case

NICE is clear that osteoarthritis can be diagnosed clinically, without imaging, in people aged 45 or over with activity-related joint pain and morning stiffness of 30 minutes or less, and that imaging should not routinely be used to make that diagnosis. The Evidence-Based Interventions guidance says the same for primary care, and names weight-bearing radiographs as the first-line imaging when imaging is needed.

Orwyn asks for weight-bearing X-rays for every suspected case of knee osteoarthritis. This is a deliberate departure from NICE NG226, owned by Dr Imbuldeniya: ‘Patients reaching MSK triage have already seen their GP and not settled. A weight-bearing X-ray confirms the diagnosis, shows how severe the wear is and rules out other causes. It is then ready if surgery is considered later, as the GIRFT knee replacement pathway expects. Treatment starts straight away, and the X-ray is reviewed at follow-up to confirm the diagnosis.’ (GIRFT is the Getting It Right First Time programme.)

The X-rays also show the alignment, for an offloading brace; the severity and pattern of wear, for a surgical opinion; and the skyline, for the joint behind the kneecap. Where osteoarthritis or malalignment is suspected, a long-leg standing view of both legs and a Rosenberg view are added; where a department cannot take long-leg films, the service’s local settings say so. The patient is seen again to go through the X-rays.

Set views for set problems

When the question is the soft tissue

An X-ray shows the shape of the joint and how much wear there is. It does not show the ligaments, the cartilage or the menisci. When the question is about those, the test is an MRI, and whether it is useful at first contact depends on what it will change: see when an MRI of the knee is useful at first contact.

How Orwyn handles this

Orwyn picks the view set from the diagnosis the clinician agrees, writes the request as weight-bearing, and puts the clinical question and the reason on it, with the findings that led to it. For a suspected fracture it also writes the plan after the X-ray, so the next step is decided before the image comes back.

The patient letter explains the test in one sentence: “I have asked for X-rays of your knee. They show the shape of the joint and how much wear there is, which helps us plan your treatment.”

The MRI request to radiology, with the clinical question and the mechanism of injury. — Example patient. An imaging request written by Orwyn; this example is for an MRI.

Sources and review

Where this came from

Stiell IG et al. Implementation of the Ottawa Knee Rule for the use of radiography in acute knee injuries. JAMA 1997;278:2075-2079. Read it here.
Osteoarthritis in over 16s: diagnosis and management, NG226. National Institute for Health and Care Excellence, 2022. Read it here.
Knee MRI when symptoms are suggestive of osteoarthritis. Evidence-Based Interventions, Academy of Medical Royal Colleges. Read it here.
BOAST: Assessment and management of first time lateral patellar dislocation. British Orthopaedic Association, December 2024. Read it here.
Suspected cancer: recognition and referral, NG12, section 1.11 (sarcomas). National Institute for Health and Care Excellence. Read it here.