Runner’s knee: why the front of your knee hurts and what actually helps

Runner’s knee is pain around or behind the kneecap. Clinicians call it patellofemoral pain, the preferred term for what has also been labeled anterior knee pain or chondromalacia patella [1]. It usually gets worse with activities that load a bent knee, such as squatting, stairs, running and jumping [1]. Pain when sitting and a grinding feeling can come with it, but they are not needed for the diagnosis [1], and that crackling sound is not harmful on its own [11].

Who gets it

Despite the name, you do not have to be a runner. Here is what the research shows:

• Runners: it made up about 17% of specific running injury diagnoses in one review [2].
• New runners: 16 of 77 women in a 10-week start-to-run program developed it [4].
• Teens: about 7% of adolescents have it at any given time [4].
• Women: in a study of 1,525 US Naval Academy participants, women were about twice as likely as men to develop it [3]. The study was done in a military setting, so it may not apply to everyone.

What causes it

A sudden change in activity, poor training technique or equipment, and changes in footwear or playing surface can all contribute [5].

Some popular explanations hold up less well. A review of 18 studies with 4,818 participants found that age, height, weight, body mass index and the angle of the knee (the “Q angle”) were not risk factors, and neither was hip weakness [6]. That does not mean strength work is pointless. It means weak hips are not proven to be the cause, even though exercise can still help.

There is no single definitive test. Pain during a squat is the most useful sign [1], and imaging usually does not help [11]. Tell your clinician if your kneecap has ever dislocated, since that is considered a separate group [1].

How long does it last?

This is the part many people do not expect: it can linger. Results from people treated in clinical trials and followed over time:

When	What the study found	People
3 months	55% had an unfavorable recovery	310 people [7]
12 months	40% had an unfavorable recovery	310 people [7]
5 to 8 years	57% had an unfavorable recovery	34 of the 60 who responded [8]

Sources: Collins et al., 2013 [7]; Lankhorst et al., 2016 [8].

Please read those numbers with care. In the 5 to 8 year study, “unfavorable” included people who had improved moderately, and only about 1 in 5 of the original participants responded [8]. In a trial that counted moderate improvement as a success, more than 7 in 10 people in every group had improved at one year [9]. A fair summary: most people get better, but many still have some symptoms a year later.

Two more useful findings. People who had pain for more than 2 months before treatment tended to do worse, which supports getting help early [7]. And in that long-term study, 48 of 50 people who had X-rays showed no signs of knee arthritis, though this was a small group [8].

What helps

The evidence on runner’s knee is mostly low certainty, with small and varied trials [12] [14]. Even so, the main recommendations are consistent.

Exercise comes first. A Cochrane review of 31 trials found that exercise reduced pain during activity by about 1.5 points on a 0 to 10 scale in the short term, though the evidence was very low quality [12]. A 2025 Dutch guideline recommends quadriceps and/or hip exercises for at least 6 to 12 weeks, preferably with at least some supervision, and suggests rechecking the diagnosis if nothing has improved by 12 weeks [10]. International experts favor hip and knee exercises together [13], but a large analysis suggests the area you train may not matter much [14]. The best exercise program is still unknown [12].

Education and changing your training matter too. A 2024 best practice guide says exercise should be built on a foundation of education [15]. In a trial of 69 runners, education about managing symptoms and adjusting training worked as well alone as it did with added exercise or gait retraining; all three groups improved similarly over 20 weeks [16]. That trial had no untreated group, so it cannot show how much of the improvement came from the education itself.

Waiting it out is not the best plan. The authors of that large analysis, which covered 22 trials, advise against simply waiting and seeing. Active care looked better at 3 months, though the differences between treatments were much less clear by 12 months [14].

Shoe inserts, tape, braces and surgery

Shoe inserts have been compared directly with physical therapy. Here is how people did in a trial of 179 adults:

• Physical therapy93%
• Physical therapy plus shoe inserts90%
• Shoe inserts85%
• Flat inserts (comparison)58%

Source: Collins et al., BMJ, 2008 [9]. One trial with no untreated group. Physical therapy included taping, joint mobilization, muscle retraining and education.

The inserts beat flat inserts at 6 weeks, but they were similar to physical therapy and added nothing when combined with it [9]. All groups improved over the year, and mild side effects were more common with the inserts [9].

• Shoe inserts: international experts support them for short-term relief [13], while the Dutch guideline saves them, along with tape and braces, for people who have not improved after 6 to 12 weeks of exercise [10].
• Tape: tailored taping can reduce pain right away, but there is limited evidence beyond that [17], and a Cochrane review found the evidence insufficient [18].
• Knee braces: a Cochrane review found no clinically important benefit when added to exercise, based on very low quality evidence [19].
• Changing your running form: for runners, raising your step rate by 5% to 10% and landing more softly have the most consistent short-term findings, and may be a useful add-on [20]. Changing your foot strike is less well supported [20].
• Pain medicine: the Dutch guideline suggests it only for severe pain, starting with acetaminophen, then an anti-inflammatory gel, with caution [10]. Ask your doctor or pharmacist what is safe for you.
• Surgery: it is very rarely needed [5]. In a small trial of 56 people, adding knee arthroscopy to home exercise gave no extra benefit after 5 years [21].

What you can do now

• Cut back on what clearly aggravates your knee and switch to lower-impact activity for a while, such as a stationary bike, an elliptical or swimming [5]
• Use pain as your guide: exercise is fine if the pain settles afterward and is no worse that night or the next morning [11]
• Give strengthening time, since it can take at least 6 to 12 weeks to notice a real difference [11]
• Use an ice pack wrapped in a towel for up to 20 minutes every 2 to 3 hours if it helps [22]
• Build your running back gradually, and watch out for sudden jumps in training [5]

See a clinician if your knee pain does not improve within a few weeks [22].

Get medical care promptly if you cannot bear weight on the knee, have severe pain even at rest, your knee buckles or locks, it looks deformed, you cannot bend or fully straighten it, or you have fever, redness, warmth or a lot of swelling. The same goes for pain, swelling, numbness, tingling or bluish color in the calf below the sore knee [23].

The takeaway

• Runner’s knee is common, and it does not only affect runners.
• Exercise and education are the first steps, and adjusting your training is a big part of it.
• Plan on at least 6 to 12 weeks, and know that some symptoms can last longer.
• Inserts, tape and form changes may help as add-ons. Braces and surgery have little support.
• Getting help early is better than waiting: longer pain tends to mean a slower recovery.

You can start physical therapy in Utah without a referral. If your knee hurts on the stairs or on your runs, an evaluation can confirm the cause and build a plan around the activities you want to get back to.