By Mr Philip Dobson, Consultant Orthopaedic Surgeon specialising in knee and hip conditions in Newcastle (Newcastle Hospitals NHS and Nuffield Health).

Many people experience knee pain during the day when walking, exercising, or climbing stairs. However, some patients find that their knee becomes more painful at night, making it difficult to get comfortable or sleep.

Night pain can be frustrating and worrying, particularly if it begins to interfere with your quality of life.

In most cases, knee pain at night is not caused by anything serious, but it can be a sign that an underlying problem requires assessment and treatment.

Why does knee pain seem worse at night?

There are several reasons why knee pain may feel more noticeable at night. During the day we are distracted by work, exercise and daily activities. At night, discomfort often becomes more apparent. Inflammation within the joint may also become more noticeable after a day of activity.

Osteoarthritis

One of the most common causes of knee pain at night is osteoarthritis.

As cartilage within the knee gradually wears away, the joint can become painful, stiff, and inflamed.

Patients with arthritis often describe:

• Aching pain in the evening
• Difficulty finding a comfortable sleeping position
• Stiffness after sitting or lying down
• Pain when getting out of bed in the morning

Night pain can be a sign that arthritis is becoming more symptomatic and beginning to affect everyday life.

Meniscal tears

The meniscus is a shock-absorbing structure within the knee.

A meniscal tear can cause:

• Pain when twisting
• Clicking or catching sensations
• Intermittent swelling
• Discomfort at night

Some patients notice that symptoms become more obvious when trying to rest after a busy day.

Inflammation within the knee

Inflammation can occur for a number of reasons, including:

• Arthritis
• Previous injury
• Overuse
• Inflammatory joint conditions

When inflammation develops, fluid may accumulate within the joint, causing pain, swelling, and stiffness.

These symptoms often become more noticeable in the evening.

When should you seek specialist advice?

Occasional knee pain at night is common and is not always a cause for concern.

However, it is sensible to seek specialist advice if:

• Pain regularly disturbs your sleep
• Symptoms are progressively worsening
• The knee is swollen
• You are struggling with walking or daily activities
• Symptoms persist despite rest and simple treatments

A detailed assessment can help identify the underlying cause and determine the most appropriate treatment.

What treatments are available?

Treatment depends on the underlying diagnosis.

Options may include:

• Physiotherapy and strengthening exercises
• Activity modification
• Pain relief medication
• Injection treatments
• Surgery where appropriate

Many patients improve with non-surgical treatment, particularly when problems are identified early. In some cases, treatment such as physiotherapy and injection therapies can help patients remain active and delay surgery for a period of time.

Could knee replacement be necessary?

Not everyone with knee pain at night requires surgery.

However, if arthritis has become advanced and symptoms are significantly affecting quality of life, knee replacement surgery may be considered.

The decision is based on symptoms, function, examination findings, and imaging rather than pain alone.

Specialist assessment

If knee pain is affecting your sleep or quality of life, a specialist assessment can help identify the cause and discuss the most appropriate treatment options, including whether treatments such as PRP (platelet-rich plasma) injections may be suitable depending on the underlying diagnosis.

Early diagnosis often allows treatment to begin before symptoms become more severe, helping patients remain active and maintain their quality of life.