The first steps in the morning hurt. After a walk along Lake Zürich, the knee swells. The stairs up to the office become a small hurdle where you hold on to the railing. These are not trivial complaints. They are the typical early signs of gonarthrosis, the degenerative disease of the knee joint. Modern pain medicine has considerably more options today than ten years ago, from targeted physiotherapy and intra-articular injections to low-dose radiotherapy. What matters is that these building blocks are used in the right order.

What knee osteoarthritis is, and what it is not

In short
Knee osteoarthritis (gonarthrosis) is the degenerative disease of the knee joint, with cartilage breakdown, secondary synovitis and a gradual loss of function. It affects a large patient population worldwide and is one of the leading causes of restricted mobility in older age [Cross et al., Ann Rheum Dis 2014]. International guidelines, above all OARSI 2019 and the EULAR recommendations, now set out a clear stepwise framework. At the base are three core interventions that every patient should receive: structured exercise therapy and strength training, weight reduction where body weight is elevated, and education that builds self-efficacy [Bannuru et al., Osteoarthritis Cartilage 2019; Fernandes et al., Ann Rheum Dis 2013]. Only once this foundation stands firm are pharmacological and interventional building blocks added, tailored to comorbidities, pain character and life situation. Coordinated from the GP practice, so that you do not have to find the specialist departments yourself.

How we classify the knee diagnostically

Most knee pain seen in a GP practice can be reliably classified through a careful history and clinical examination. The key questions have been stable for years. When does it hurt, and under what kind of load? How long does the morning start-up pain last? Is there swelling, warmth, an audible grinding? This history often tells us more than an X-ray [Hunter and Bierma-Zeinstra, Lancet 2019].

Imaging is used where it answers a question. We do not order it by reflex. A conventional standing X-ray shows joint-space narrowing, subchondral sclerosis and osteophytes. An MRI makes sense in younger patients, where an accompanying meniscus or ligament injury is suspected, or when the symptoms do not match the X-ray. We go through the findings together, including the important message that radiological findings do not correlate one to one with the pain you experience.

Conservative stepwise therapy

The international guidelines largely agree that every treatment of knee osteoarthritis begins with the same core interventions. OARSI 2019 calls them "core treatments" and recommends them regardless of stage and regardless of whether comorbidities are present [Bannuru et al., Osteoarthritis Cartilage 2019]. EULAR 2013 phrases them as non-pharmacological core recommendations [Fernandes et al., Ann Rheum Dis 2013]. The American ACR update of 2019 follows the same logic [Kolasinski et al., Arthritis Rheumatol 2020].

In concrete terms, this is what it means for you, in this order:

  • Structured exercise therapy: building up the muscles that stabilise the joint, above all the quadriceps, guided by a physiotherapist with experience in musculoskeletal rehabilitation.
  • Weight management where BMI is elevated: every kilogram lost significantly reduces the mechanical load on the knee. Where needed, we coordinate with dietary counselling.
  • Education and self-management: understanding what knee osteoarthritis is and what it is not is an intervention in its own right, with a proven effect on pain and function.
  • Topical NSAIDs as the first medication step: diclofenac gel has a more favourable side-effect profile than oral NSAIDs and is the preferred choice in the guidelines.
  • Oral NSAIDs for a limited period: if necessary, at the lowest effective dose, with your cardiovascular, renal and gastrointestinal risk taken into account.
  • Considering intra-articular injections: corticosteroid injections for acute inflammatory flares, hyaluronic acid for selected patients who respond insufficiently to the basic therapy.

Wherever possible, we try to separate the mechanical component from the inflammatory one clinically. Anyone whose knee takes a long time to "warm up" in the morning often has more pronounced inflammatory activity. Anyone with pain mainly after exertion is more likely mechanically dominated. This distinction influences the choice of the next step.

Multimodal pain therapy at Dein Team fürs Leben

The pain consultation service in Zürich combines GP coordination with specialised pain medicine. We discuss your case, review your imaging with you and put the treatment plan together.

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When basic therapy is not enough: interventional and multimodal options

For some patients, conservative basic therapy is not sufficient. Then it is worth looking at the next level. Multimodal pain therapy goes beyond any single measure. It is a planned combination of physical-functional, pharmacological and psychosomatic treatment, coordinated through one main point of contact. In inflammatory-activated knee osteoarthritis, targeted interventional procedures are an additional option.

One option that has attracted renewed attention in recent years is low-dose radiotherapy (LDRT). The evidence is mixed. In two randomised, sham-controlled trials from the Netherlands, LDRT showed no benefit over sham irradiation in the primary endpoints for hand and knee osteoarthritis [Minten et al., Osteoarthritis Cartilage 2018; Mahler et al., Ann Rheum Dis 2019]. Other observational studies report a marked reduction in pain in some of those treated. That makes the indication a case-by-case decision, ideally taken jointly by pain medicine, radiation oncology and the patient. We discuss benefits, limitations and realistic expectations openly.

CT-guided intra-articular infiltrations, placed precisely at the pain-generating structure, open a therapeutic window in which active physiotherapy becomes possible in the first place. This does not replace exercise therapy. It is the bridge to it.

When a surgical solution enters the conversation

A knee replacement is a successful operation. It is also a major operation, with a rehabilitation period and potential complications. The international guidelines agree on this: it comes at the end of the stepwise plan, never at the start [Bannuru et al., Osteoarthritis Cartilage 2019]. The indication can be summarised well: persistent pain despite conservative therapy carried out consistently over several months, marked functional limitation in everyday life, and an imaging finding that plausibly explains the clinical burden.

We do not step back at this point. We coordinate a second opinion from a knee-specialised orthopaedic clinic, review the timing together and accompany you preoperatively so that you go into surgery in the best possible physical condition. After the operation, the GP practice remains your point of contact for pain management, wound checks and rehabilitation planning.

What to expect from us

We take time for a detailed history, review any existing imaging with you, and put the stepwise plan together with you. For cardiovascular questions, which regularly play a role in NSAID selection or with comorbidities, we obtain a cardiological second assessment from Prof. Dr. Gloekler. First contact requires no referral and is usually possible within a week. Languages: German and English.

Knee consultation at Dein Team fürs Leben

First contact without a referral. Appointments usually within a week. Bring any existing imaging (X-ray, MRI), your current medication list and reports from the last two years.

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Frequently asked questions

:::faq

Can knee osteoarthritis be cured?

Strictly speaking, no. The loss of cartilage is irreversible. Pain and function, however, can be markedly improved in most patients when the conservative basic therapy is carried out consistently and the further building blocks are used in an orderly sequence.

Should I keep walking with knee pain, or rest?

As a rule: keep walking, but in a structured way. Complete rest weakens the muscles that stabilise the joint and worsens the prognosis. The guidelines recommend active exercise therapy as a core intervention, guided by a physiotherapist [Bannuru et al., Osteoarthritis Cartilage 2019].

How effective are hyaluronic acid injections into the knee?

The evidence is heterogeneous. The international guidelines differ, from a cautious recommendation (OARSI, ACR) to an option for selected patients. We discuss realistic expectations with you before we decide whether it is indicated.

What does low-dose radiotherapy of the knee achieve?

The evidence from randomised trials is mixed. Two sham-controlled trials from the Netherlands showed no significant benefit [Minten et al., Osteoarthritis Cartilage 2018; Mahler et al., Ann Rheum Dis 2019]. In strongly inflammatory-activated osteoarthritis with an insufficient response to conservative stepwise therapy, it can be considered on a case-by-case basis, in close coordination with radiation oncology.

When is the right time for a knee replacement?

When the burden persists for months despite consistently applied conservative therapy, function is clearly limited and the imaging plausibly explains the symptoms. We coordinate the orthopaedic second opinion and discuss the timing together.

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Written by Prof. Dr. C. K. Fritz M.Sc. · Physician Associate in General Internal Medicine, Pain Medicine, Practice Lead Dein Team fürs Leben.