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Many people never grow out of their growing pains

A new research project from Aarhus University shows that many adolescents suffer from knee pain for several years. The pain impacts both sporting activities and quality of life.


Over the years, many adolescents have been forced to accept the diagnosis "growing pains" when they complained about pain in their knees. A new PhD study involving 3,000 adolescents has now shown that the knee pain often carries on:

"We can see from the study that one in three young people between the ages of 12 and 19 experience problems with pain in their knees. Seven percent of the adolescents experience daily knee pain in the front of the knee," says physiotherapist and PhD Michael Skovdal Rathleff from Aarhus University, and continues:

"More than half still have problems after two years, so it is not something they necessarily grow out of." 

Poorer quality of life

The study thus suggests that knee pain is a bigger problem than previously assumed. According to the researcher there are several good reasons to take knee pain more seriously in the future:

"If knee pain is not treated there is a high risk of the pain becoming chronic. And this clearly has a big consequence for the individual's everyday life and opportunities. In fact, our findings show that these adolescents have as much pain symptoms and reduced quality of life as adolescents on a waiting list for a cruciate knee ligament reconstruction, or as a 75-year-old six months after receiving a new knee.

"Secondly, we can see that this group of adolescents often stop doing sport because of the knee pain. This is, of course, extremely unfortunate, because we know that it is very difficult to start again once you have stopped," says Michael Skovdal Rathleff.

Other surveys show that approximately one third of adult Danes suffer from pain in their knees, and also that approximately 25 percent of the patients who have received new knees due to osteoarthritis of the kneecap also state that they have suffered from knee pain since adolescence. This suggests that osteoarthritis of the kneecap can in some cases begin with knee pain during adolescence.

Need for earlier treatment

According to Michael Skovdal Rathleff, the good news is that the pain disappears with the right training in the case of up to half of the young people. However, it can be a challenge to fit such training into the daily life of an adolescent. And an early effort is important:

"It is worrying that the pain only disappears in the case of half of the young people who actually do the training. The indications are that we should start the treatment somewhat earlier where it is easier to cure the pain. Though this does not necessarily mean that all adolescents with bad knees must visit a physiotherapist. A closer cooperation between physiotherapists and general practitioners about how to best help these young people could also be a solution," concludes Michael Skovdal Rathleff.

The project’s findings have been published in the recognised scientific journal BMC Pediatrics.

Facts about the study

  • 3,000 adolescents took part in a preliminary questionnaire-based survey in 2011.
  • Aged 12-19 they were pupils at primary and upper secondary schools in Aalborg Municipality.
  • 504 adolescents between the ages of 15 and 19 stated that they suffered from knee pain and were subsequently followed in the study.
  • 153 of them were diagnosed with Patellofemoral Pain Syndrome (PFP), which is the most common and most serious knee diagnosis.
  • 55 percent of the adolescents with PFP still suffered from knee pain after two years.
  • On 16 June 2014, Michael Skovdal Rathleff defended his PhD on the subject. 




Physiotherapist and PhD student Michael Skovdal Rathleff
Aarhus University, Department of Clinical Medicine and
Aalborg University Hospital, Department of Occupational Therapy and Physiotherapy
Tel.: +45 2211 7002 / +45 9932 1111
msr@clin.au.dk / misr@rn.dk