Knee osteoarthritis: before anyone talks about a new knee

Clinical Rounds, the GPAtlas podcast. Musculoskeletal (MSK). 17 minutes. Published 24 October 2026. Free to listen.

From our Ocean topic Osteoarthritis (Knee OA), reviewed November 2025.

Transcript

Sarah: Hello, and welcome to GPAtlas Clinical Rounds. I'm Sarah, and this is the podcast where we take one thing you'll genuinely see this week and work out what to do with it.

Ben: And I'm Ben. Today it's knee osteoarthritis, and this week's news about digital tools for people having a joint replacement. The sharp angle: most of these knees never get near an operation, and the X-ray won't tell you which ones will.

Sarah: So. Linda is sixty-eight, a retired dinner lady, and she's booked in about both knees. They ache going downstairs. They're worse after the grandchildren have stayed. They're stiff for about ten minutes in the morning, then they loosen off. She's read there are apps now to get you ready for a new knee, and her sister's just had one. She wants an X-ray and a referral. And the version of me running forty minutes late fills in the X-ray form and lets the report decide.

Ben: Three things today. Why you don't need that X-ray to make the diagnosis. Why exercise and weight loss are the actual treatment, not the warm-up act. And where drugs, injections and surgery fit, including those digital tools.

Sarah: Let's start with the news, because Linda more or less brought it in with her. She'd read about apps for people having knee surgery. So what's actually changed this week?

Ben: NICE now recommends digital tools to support people preparing for, and recovering from, hip and knee replacement. That's the news. It's for people who are already heading for surgery. It doesn't tell you who should be heading there, and it doesn't change anything you do before that point.

Sarah: Which is the bit I'd been skipping past. Linda heard 'app for your new knee' and took it to mean the new knee was the next step. And I'll be honest, I nearly went along with it. It's an easy conversation. It's what she came in wanting.

Ben: But the bar for referral hasn't moved. You refer for joint replacement when symptoms substantially affect quality of life and non-surgical management is ineffective or unsuitable. Both halves. Linda's knees do affect her life. But she hasn't had any non- surgical management yet. So the surgery tools aren't her question today.

Sarah: The new digital tools help people already heading for surgery. They don't change who gets referred.

Sarah: So, back to the X-ray she asked for. My instinct, if I'm honest, is that I want a picture before I put the word arthritis in the notes. It feels more solid. Is that wrong?

Ben: For a typical knee, yes. The diagnosis is clinical. Three things. Forty-five or over. Pain that comes with activity. And either no morning stiffness, or stiffness that settles within thirty minutes. If all three are there, you diagnose knee osteoarthritis without imaging. Imaging is for atypical features.

Sarah: And Linda ticks every box. Sixty-eight, aches on the stairs, ten minutes of stiffness. So the question that matters isn't whether we've scanned it. It's how long are you stiff in the morning. Then, does it ease when you rest. Then, one knee or both, and where exactly does it hurt.

Ben: That's the mechanical pattern. Worse with use, better with rest. Add crepitus, bony swelling, a reduced range, and trouble with stairs, walking or kneeling, with no systemic illness. And look at who it is: older, overweight, a past injury or meniscectomy, a kneeling or lifting job, family history. It's commoner in women too.

Ben: Forty-five or over, activity pain, stiffness thirty minutes or less. That's the diagnosis. No scan.

Sarah: But Linda pushed back. She said her sister's X-ray showed bone on bone, and that's why she got her operation. How could I know how bad hers was without looking? And I didn't have a great answer in the moment.

Ben: Here's the answer. The damage on X-ray correlates poorly with how much pain someone has. Plenty of people with advanced changes have very little pain. Others with severe pain show only modest changes. So the film rarely changes what you do. And it can feed exactly that bone on bone fatalism.

Sarah: That's the phrase I hear most. And once someone's been told it, they stop moving, because they think every step grinds it away. So I've started calling it wear and repair. The cushioning thins, the joint changes shape, but staying active is safe, and most people manage well without surgery. So when does an X-ray earn its place?

Ben: Two situations. Atypical features, like trauma, locking or rapid deterioration. Or assessing severity before a surgical referral. It's a weight-bearing film, and it's never to confirm osteoarthritis. MRI is rarely indicated in primary care for uncomplicated osteoarthritis. It's for suspected meniscal, ligament or other internal problems, and it's specialist-initiated.

Sarah: Treat the patient, not the X-ray. A film only for atypical features or before a surgical referral.

Sarah: Now, the reason I still feel twitchy about not scanning is the fear of missing something else entirely. So what makes you stop and think, this isn't osteoarthritis at all?

Ben: Top of the list. A hot, red, swollen, acutely painful joint. Think septic or crystal arthritis, and that's same-day assessment or admission. Fever or systemic upset with a swollen joint, same thinking, urgent assessment. If septic or crystal arthritis is suspected, the joint gets aspirated, usually in secondary care.

Sarah: And the inflammatory one is the one I think we miss in a ten-minute slot. The person who says it's worst first thing and loosens up once they're moving. I'd want bloods there. But they don't help much in osteoarthritis itself, do they?

Ben: No. A full blood count, ESR and CRP are normal in osteoarthritis. They're for excluding inflammation or infection when you suspect it. And what you've described is the reverse pattern: stiffness over thirty minutes, pain worse at rest and easing with movement. That's suspected inflammatory arthritis, so rheumatology. Night pain at rest with weight loss or past cancer, think bone pathology. True locking, orthopaedic or musculoskeletal assessment.

Ben: Stiff over thirty minutes or better with movement, think inflammatory. Hot, red and swollen, think septic, same day.

Sarah: Here's one that caught me out a few years ago. Man in his seventies, knee pain, knee examination completely normal. I gave him knee advice and a knee leaflet. Six weeks later he was back, and it was his hip all along.

Ben: It's the classic pitfall. Knee pain is often referred from the hip. So always examine the hip, especially when the knee looks unremarkable, when the pain's at the front or in the thigh, and in older adults or children. A normal knee with restricted, painful hip rotation points to the real source.

Sarah: So with Linda I did the knees properly and then rolled both hips. They moved freely, no pain. So it really was the knees. But what am I actually looking for at the knee itself, beyond a general prod?

Ben: Inspect for an effusion, varus or valgus deformity, and quadriceps wasting. Feel the joint line, the bony swelling and any warmth. Warmth or a tense effusion points away from simple osteoarthritis, towards inflammation or infection. Check crepitus and range, test the ligaments for laxity. Then watch her walk, get up from a chair and squat.

Sarah: Knee pain with a normal knee? Examine the hip. Every time.

Sarah: So, management. And I'll admit, exercise used to be the thing I said on the way to the prescription. Keep active, here's your gel. Linda's quads were thin when I examined her, though, and that changed how I thought about it.

Ben: Because that's backwards. Therapeutic exercise and weight management are the core treatments. They reduce pain and improve function. Offer them to everyone, start them before any drug, and keep them going alongside. Exercise is the single most effective intervention. Local strengthening, especially the quadriceps. Plus aerobic fitness: walking, cycling, swimming.

Sarah: What sinks it, in my experience, is week two. They start the exercises, the knee aches a bit more, they decide they've damaged it and stop. With Linda I asked what mattered most. Lifting her granddaughter, and getting to the allotment. I asked about sleep and mood too. She admitted she'd been low.

Ben: Good, because persistent joint pain commonly affects both. And for week two, tell them before it happens. Joint pain may increase a little when they start. Consistent, long-term activity is safe, and it's what delivers the benefit. Tailored to her, with supervised sessions where available. That's your physiotherapy referral.

Ben: Exercise is the treatment, not the afterthought. Warn about the early ache, then keep going.

Sarah: Weight is the harder conversation. Linda's put on a couple of stone since she retired, and she knows it. She's also heard it from every doctor she's seen, so she's braced for a lecture before I've opened my mouth.

Ben: So make it about the knee. Overweight and obesity is the main modifiable risk factor. If someone's overweight, any weight loss helps, and losing ten per cent is better than five. It reduces joint load, pain and disability. That's a treatment for her knees, not a judgement about her.

Sarah: Any loss helps was the bit she could actually hear. Then she asked about all the other things. A brace from the chemist, special insoles, the knee support her sister swears by. And I realised I didn't have a clear answer on any of them.

Ben: Insoles and braces aren't routine. Only where there's instability or abnormal loading and exercise alone isn't enough. Manual therapy only alongside exercise, never on its own. Local heat or cold packs for short-term relief. And consider a walking stick, held in the opposite hand. Occupational therapy can help with aids and adaptations.

Sarah: Any weight loss helps, and ten per cent beats five. Stick in the opposite hand. Braces only for instability.

Sarah: Right, drugs. Linda's been taking paracetamol most days for a year, and she says it does nothing. My reflex is to add codeine. Should I be surprised it isn't working?

Ben: No. There's no strong evidence of benefit for paracetamol. Paracetamol and weak opioids like codeine aren't offered routinely, only for infrequent, short-term pain when everything else is contraindicated, not tolerated or ineffective. And opioids carry a dependence risk. First-line for the knee is a topical non-steroidal anti-inflammatory, a topical NSAID. Ibuprofen gel or diclofenac gel. Low systemic absorption, so it's the safest first choice.

Sarah: And if it's ketoprofen gel, I'd add sun protection advice, because it can cause photosensitivity. So Linda started a topical NSAID alongside the physio. Not instead of it. But say the gel isn't enough in a month. Then it's oral?

Ben: Oral ibuprofen or naproxen, lowest effective dose, shortest course, with a proton pump inhibitor, a PPI, throughout. Care, or avoid, in heart failure, chronic kidney disease, peptic ulcer disease, older patients, and with anticoagulants or antiplatelets. Naproxen has the more favourable cardiovascular profile. And the MHRA advice is that systemic diclofenac is contraindicated in established ischaemic heart disease, peripheral arterial disease, cerebrovascular disease, and heart failure of New York Heart Association class two to four.

Ben: Topical NSAID first, always alongside exercise. Don't offer glucosamine, chondroitin or strong opioids.

Sarah: Last piece. Injections. Linda's sister had a steroid injection while she was waiting for her operation, so of course Linda asked whether she could have one now, and get it over with.

Ben: Consider an intra-articular corticosteroid when other treatments aren't working or aren't suitable, or to help someone get going with exercise. Methylprednisolone acetate or triamcinolone. Explain it's short-term relief, two to ten weeks. A flare afterwards is possible. A small, brief rise in blood glucose in diabetes. Limit repeat injections into the same joint. And don't offer hyaluronan injections at all.

Sarah: So here's what Linda got in the end. The diagnosis, no X-ray. The wear and repair explanation. A physio referral for supervised exercise, a topical NSAID, a patient leaflet, and patient-initiated follow-up with a clear safety net. She left a bit surprised. But she did ask, what if it doesn't work?

Ben: Then you're back to the referral test. If her symptoms substantially affect her quality of life and non-surgical management has been ineffective or unsuitable, you refer. That's when she's heading for surgery, and that's where the digital preparation and recovery tools in the news come in. Not before. And nothing in that news changes the steps that come first.

Sarah: A steroid injection buys two to ten weeks. Refer when life's substantially affected and non-surgical care is ineffective or unsuitable.

Ben: Right, exam corner. A seventy-one-year-old man has knee osteoarthritis. He had a stent for ischaemic heart disease three years ago. He's doing his physiotherapy exercises and has used a topical NSAID, but the pain is stopping him keeping up the exercise. What's the most appropriate next step? A, oral diclofenac with a proton pump inhibitor. B, glucosamine. C, an intra-articular hyaluronan injection. D, an intra-articular corticosteroid injection to support his exercise.

Ben: D. An intra-articular corticosteroid can be considered when other treatments aren't working, or to support exercise, with short-term relief of two to ten weeks. A is the tempting one, because an oral NSAID is the usual next step after a topical. But systemic diclofenac is contraindicated in established cardiovascular disease, and his ischaemic heart disease counts. Glucosamine and hyaluronan injections aren't offered at all.

Sarah: So. Three things for Monday. One. Forty-five or over, pain with activity, stiffness thirty minutes or less: that's knee osteoarthritis, and you don't need an X-ray. Two. Exercise for everyone, and weight loss if they're overweight, before and alongside any drug. And warn them about the early ache. And three. Examine the hip. Then refer for replacement when life's substantially affected and non-surgical care is ineffective or unsuitable.

Sarah: One thing to reflect on, if you're logging this. Think of the last knee X-ray you requested for someone over forty-five. Did the report change a single thing you did next? The full transcript and the sources are on the episode page. Ben and I are natural AI voices, and what we've said comes from our reviewed Ocean topic. Check your local guidance before you act on it. See you next week.

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