Multidimensional Diagnostics and Effect of Activity Modification in Young Adolescents With Patellofemoral Pain
Condition: Patellofemoral Pain Syndrome
MeSH terms: Patellofemoral Pain Syndrome
Study type: Interventional

Summary: 
      Problem: Adolescent patellofemoral pain (PFP) is a major problem worldwide and affects 7% of
      adolescents. Adolescents with PFP have long-lasting severe pain and low quality of life.
      Current treatment is ineffective for more than 60% and new treatment approaches are needed.

      Solution: A novel multidimensional diagnostic approach combining imaging, physical activity
      level and pain sensitisation in adolescents with PFP. This approach will enable the
      identification of adolescents with PFP who benefits from a new treatment strategy using
      activity modification to reduce loading of the patellofemoral joint and graded exercises to
      improve loading capacity.
    

Detailed description: 
      Participants:

      Adolescents will be recruited from a population-based cohort from Aalborg and Copenhagen
      consisting of a total of 16 public schools. This cohort will allow for recruitment of
      adolescents with PFP from the following categories 1) adolescents not participating in sport
      outside school; 2) adolescents involved in sports a minimum of 3 times per week. In addition,
      a randomly recruited age- and gender-matched pain-free group from the same cohort will be
      recruited to form a control group.

      Protocol:

      All adolescents will be requested to complete an online questionnaire on current pain
      problems. If they report having knee pain they will be telephoned. The telephone interview
      will collect an anamnesis and the adolescents and their parents will be invited to a clinical
      examination if they have anterior knee pain with an insidious onset and with duration of more
      than 6 weeks. If the adolescents are diagnosed with PFP they are invited to participate in
      the project.

      Baseline measurements:

      PFP will be diagnosed using eligibility criteria in line with previous clinical trials and
      commonly accepted criteria. All adolescents with PFP from the cohort will be examined using
      self-report questionnaires, clinical examination, strength of the hip and knee, MRI and
      pressure pain thresholds. Pressure pain thresholds will be measured around the knee, lower
      leg and forearm to assess local and secondary mechanical hyperalgesia and thus the
      sensitisation of the central nervous pain system. Additionally, cuff-algometry will be used
      to asses temporal summation of pain during repeated stimuli and conditioned pain modulation.
      The pain-free control group will be examined using the same measurements. The comparison
      between adolescents with PFP and the pain-free control group will be used in 1-2 descriptive
      studies with the main purpose of describing this young population based on self-report
      questionnaires, MRI-scans, strength of the hip ad knee and pain mechanisms.

      Main study:

      Adolescents with PFP will be asked to participate in main study which investigates the effect
      of early activity modification and graded exercises among adolescents with patellofemoral
      pain.

      Using a prospective cohort design the investigators will investigate the effect of a novel
      treatment strategy aimed at temporary reduction in the loading of the patellofemoral joint by
      activity modification. After inclusion, the custody holder and the adolescent with PFP will
      be informed to begin a 4 week activity modification period and avoid all sports activity
      including school sports. This protocol will cause a temporary reduction in the loading of the
      patellofemoral joint. At 4 weeks they are instructed to begin a predefined training protocol
      involving graded exercises. The purpose of the graded exercises is to increase loading
      capacity of the tissue around the knee.
    

Intervention name(s): Temporary activity modification and graded exercises
Intervention type(s): Other
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Treatment