Adolescent Patellofemoral Pain

Original Editor - Stacy Schiurring based on the course by Claire Robertson

Top Contributors - Stacy Schiurring, Jess Bell and Kim Jackson

Introduction[edit | edit source]

Patellofemoral pain is common in the adolescent population and can be challenging to treat.[1] According to Rathleff et al.,[2] approximately 6 -7% of the adolescent population will experience some sort of patellofemoral pain, but this number could be as high as 29% according to Fick et al.[3]

This pain is not self-limiting. Research has shown that if it is not adequately treated it can persist on into adulthood.[1] It is, therefore, important to recognise this diagnosis in the adolescent population and provide appropriate interventions to allow them to keep up with their peers and enjoy being a sporty kid. This article will provide an overview of patellofemoral pain in adolescents, discuss common differential diagnoses, and offer treatment options for this challenging demographic.

Patellofemoral Pain in Adolescents[edit | edit source]

"Patellofemoral pain is a frequent knee condition, characterized by retropatellar or peripatellar pain. This condition is especially present in young, physically active individuals and seems to arise during puberty."[4]

Research is beginning to show that patellofemoral pain can linger for an extended amount of time from adolescence into adulthood. In the adult population, success rates of symptom improvement using exercise therapy is approximately 60% at the 12-month follow-up.[4] According to a 2015 article by Rathleff et al.,[5] 62% of adolescents report continuing persistent symptoms 12 months after the completion of exercise therapy.[4]

Adolescent patellofemoral pain can affect the individual in terms of a loss of educational opportunities, reduced time in recreational and or competitive sports, and decreased ability to maintain a healthy lifestyle. In addition to physical symptoms, adolescents with patellofemoral pain can develop mental health and self-esteem issues due to changes in their lifestyle. This pain can remain unresolved for years after symptom development, and there is growing evidence that adolescent patellofemoral pain is a precursor to the development of adult osteoarthritis.[3] Four out of ten adolescent patients with patellofemoral pain will continue to have symptoms into early adulthood at a level severe enough to affect their quality of life.[6]

Recent research has focused on the cause of adolescent patellofemoral pain being multifactorial and includes alterations in (1) neuromuscular control, (2) limb alignment, and (3) patellar tracking.[3]

The evidence-based management and treatment of adolescent patellofemoral pain is also limited as most of the research is based on the adult population.[3] One significant difference between patellofemoral pain in the adult population compared to the adolescent population is a lack of weakness as a primary symptom in adolescents. Adolescents may become less active and, therefore, develop muscle weakness as a result of their pain, but it is not the primary driver.[1] Treatment in adolescents is further complicated by their rapid musculoskeletal growth and the changes in knee morphology. Research is pointing to an association between adolescent patellofemoral pain and alterations in patellar bone shape. Similarly, there may be an association with patellar dislocation and the onset of adolescent patellofemoral pain.[3]

Differential Diagnosis[edit | edit source]

When a patient presents with patellofemoral pain, it is important to be mindful of possible differential diagnoses which could masquerade as patellofemoral pain syndrome.[1]

Osgood Schlatter Disease[edit | edit source]

Osgood Schlatters Disease.png

To learn more about Osgood Schlatter disease (OSD, also known as osteochondrosis, tibial tubercle apophysitis, or traction apophysitis of the tibial tubercle)[7], please read this optional article.

Patellofemoral pain and OSD are the two most common causes of knee complaints in adolescents, and understanding the difference between these two conditions is important in effective treatment and pain management.[2]

Key signs and symptoms for differential diagnosis:[7]

  • OSD is an overuse injury of the patellar tendon which occurs secondary to repetitive extensor mechanism stress activities such as jumping and sprinting
  • typically occurs at ages 10-12 in girls and at ages 12-14 in boys
  • sudden skeletal growth is a known risk factor
  • anterior knee pain is atraumatic with tenderness at the patellar tendon insertion site at the tibial tuberosity
  • notably enlarged prominence at the tibial tubercle
  • can present with or without swelling
  • pain starts as a dull ache localised over the tibial tubercle and gradually increases with activity
  • pain is exacerbated with activity, especially running, jumping, new direct knee trauma, kneeling and squatting
  • pain typically improves with rest, and will cease within hours of stopping the activity
  • predisposing factors include poor flexibility of quadriceps and hamstrings
  • pain may be reproduced by performing resisted knee extension, and active or passive knee flexion
  • confirmation on MRI to show level of inflammation[1]

A 2020 study by Rathleff et al.[2] looked at adolescents aged 10 to 14 years with a diagnosis of PFP or OSD and found that they continued to participate in "high levels of vigorous physical activity even in the presence of long-standing knee pain." The study participants reported difficulty with sports participation and impaired knee function. They also reported having to stop or reduce their sporting activities due to knee pain. However, the participants continued to be very physically active, participating in approximately two hours of vigorous physical activity (such as jogging, bicycling, and soccer) per day.[2] This patient population cumulatively puts a large load through their knees. Rehabilitation professionals need to provide education and advise these adolescents to be proactive and reduce their activity before the knee pain becomes too great.[1]

Other treatment strategies to consider as part of a rehabilitation plan of care for OSD include load modification, local ice massage, non-steroidal anti-inflammatories as necessary, and tracking patient growth patterns.[1]

Sinding Larsen Johansson Syndrome[edit | edit source]

Area of pain in SLJS versus OSD is a key sign for differential diagnosis

To learn more about Sinding Larsen Johansson Syndrome (SLJS), please read this optional article. This diagnosis is often missed or misdiagnosed as a tendinopathy.[1]

Key signs and symptoms for differential diagnosis:[8]

  • SLJS is caused by traction on the patellar ligament, causing inflammation at the insertion of the proximal ligament into the inferior pole of the patella
  • typically occurs in young active boys aged 10 to 13 years
  • tenderness at the inferior pole of the patella and possibly along the patellar tendon
  • there may be some localised soft tissue swelling
  • pain is often worse with exercise, stair climbing, squatting, kneeling, jumping and running
  • patient may report that they limp after exercise
  • pain is relieved by rest
  • resisted knee extension may elicit pain
  • confirmation on MRI to show level of inflammation[1]

Treatment strategies to consider as part of a rehabilitation plan of care for SLJS include: load modification, local ice massage, non-steroidal anti-inflammatories as necessary, removal of risk factors, and tracking patient growth patterns.[1]

Osteochondritis Dissecans[edit | edit source]

To learn more about osteochondritis dissecans (OCD), please read this optional article.

Key signs and symptoms for differential diagnosis:[9]

  • fluid effusion is the biggest clue
  • may be painful
  • involved knee may feel warmer than the non-involved knee
  • quadriceps muscle atrophy
  • onset normally unrelated to trauma
  • passive and active extension of the knee is limited
  • reports of catching or locking of the knee
  • tibial external rotation during gait
  • positive Wilson's Test
  • urgent orthopaedic referral required

Effusion can be the cause of patellofemoral pain because it triggers an alteration in quadriceps firing. The most common cause of knee effusion in a teenager is OCD[1] (it can also be known as juvenile form, JOCD).[9] If the cartilage is unstable and the condition has progressed far enough, it will slough off and create an effusion, which may cause patellofemoral pain. This condition requires urgent assessment by an orthopaedic specialist for surgical consultation and intervention.[1]

Less Common Differential Diagnoses[edit | edit source]

  • Slipped epiphysis
  • Femoral acetabular impingement (FAI)
  • Leukaemia*
  • Metastatic neuroblastoma*
  • Primary bone tumour*
  • Systemic auto-immune disease


* Any patient with the red flag symptom of night pain requires urgent assessment and screening for cancer.[1]

Treatment of Adolescent Patellofemoral Pain[edit | edit source]

Activity Modification and Load Management[edit | edit source]

Activity modification and load management are key to the management of adolescent patellofemoral pain. Dr Michael Rathleff has found in his research that exercise load is very polarised in adolescent patients with patellofemoral pain: they are either very sedentary or exercising more than five times a week.[1] In 2019, Rathleff et al.[6] looked at activity modification and load management in adolescents aged 10-14 years with patellofemoral pain. The participants attended 12-weeks of physiotherapy education and training of active modification. Weeks 0-4 involved a reduced load on the patellofemoral joint using an "activity ladder" based on current subjective pain levels. Weeks 5-8 utilised home-based exercises, and weeks 9-12 involved return-to-sport guidance. At the 12-month follow-up, 81% of participants had returned to playing sport, 90% reported being satisfied with the intervention and 95% would recommend it to a friend. This study showed that a treatment intervention with a focus on activity modification and load management could result in high outcome success rates for adolescents with patellofemoral pain, both short and long term.[6]

Providing the patient and their family with a way of tracking their activity can be a useful way to reveal their cumulative exercise load. This also provides a way for the rehabilitation professional to discuss options for activity modification, for example: play a different position during a casual game which involves less stress. School holidays can also highlight differences in load management; many student-athletes will participate in minimal sport / activity over a holiday break, but then return to full activity with the resumption of school. Therefore, assessing load volume can be helpful.[1]

An example load assessment table can be found and downloaded for clinical use in the additional resources section below.

Neuromuscular Control[edit | edit source]

Behera et al.[10] found that a rehabilitation programme which includes agility and perturbation training can have significant improvements in pain, function and balance in adult subjects aged 20-40 years with patellofemoral pain syndrome. Assessing neuromuscular control is especially valuable around times of growth.[1]

Kinesiophobia[edit | edit source]

There is a growing body of evidence in recent years on kinesiophobia. For many adolescent athletes, particularly those involved in jumping sports, poor landing technique where the shock is not absorbed in hip and knee flexion may be more linked with fear of movement than a lack of strength.[1]

Kinesiophobia is defined as an excessive irrational and debilitating fear of movement or physical activity. The fear of motion is associated with a feeling of vulnerability to injury in response to movement. The advancement of acute pain to persistent and chronic pain occurs as a result of decreased use of the painful area due to fear of an increase in pain as a result of movement.[11]


Huang et al.[12] performed a systematic review to compare interventions for kinesiophobia in individuals with musculoskeletal pain. They found that multi-modal protocols, which included physiological, and psychological perspectives in addition to more traditional therapy interventions and nature therapy were better for treating kinesiophobia caused by musculoskeletal pain when compared with active physical exercise and supervised training interventions only.[12]

Managing a patient with kinesiophobia:

  • utilise an assessment tool such as the Tampa Scale of Kinesiophobia
  • identify functional movements that elicit the fear avoidance and altered movement pattern
  • provide patient education and graded exposure

The following short video gives a general overview of exercise grading for patients with pain diagnoses.

[13]

Education[edit | edit source]

The work of physiotherapist Dr Mitchell Selhorst provides useful information on how to educate adolescents. His work includes the creation of this psychological model and framework for providing education:

  1. Identity
  2. Cause
  3. Timeline
  4. Consequences
  5. Controllability


Selhorst et al.[14] created an eight-minute video based on these features and showed it to adolescents with patellofemoral pain. The authors measured for kinesiophobia, catastrophisation, and anterior knee pain score prior to viewing the video, just after viewing the video and post two weeks. The results were remarkable, one viewing of an eight-minute video resulted in an immediate and sustained (two-week) reduction in kinesiophobia, catastrophisation, and pain. This study shows the importance of including these educational elements into treatment interventions for this patient population by empowering them to see they have some control over their rehabilitation.[14][1]

Growth Charting[edit | edit source]

  • Important for this population, particularly during times of aggressive growth
  • Allows for tracking and anticipation of bodily changes such as changes in muscle tightness
  • Allows rehabilitation professionals to anticipate needed exercise interventions such as stretching programmes[1]
  • Opportunity for patient education about changes in their body and how they can impact their sport

Special Considerations[edit | edit source]

Patellofemoral Instability and Dislocation[edit | edit source]

Patellofemoral instability is a common presentation amongst the adolescent population, and approximately one-third of all primary dislocations will go on to have another dislocation.[1]

Patellofemoral instability risk factors for repeat dislocation:

  1. First dislocation happens before the age of 14
  2. History of contralateral dislocation
  3. Any type of trochlea dysplasia
  4. Skeletal immaturity
  5. Anatomically long patella tendon


It is important that rehabilitation professionals are aware of this information because, if an adolescent patient has the last four risk factors, they are 88% likely to have a recurrent dislocation. This patient cohort as a whole has a recurrence rate of 34.7%, with 97% of recurrences happening within 3 years. The mean age at initial dislocation of those who re-dislocated was 12.9 years. Those who did not re-dislocate had a mean age of 13.8. This shows the importance of age 13 as a milestone in this field.[1]

This knowledge should lower the threshold for a referral to an orthopaedic specialist as this patient population is less likely to have a positive outcome with physiotherapy alone.[1]

Hypermobility[edit | edit source]

Adolescent patients with patellofemoral pain often do not lack strength. However, those who also have hypermobility of the patellofemoral joint may benefit from a strengthening programme. A patient with hypermobile patellofemoral joint may experience sheering forces and irritation to parapatellar soft tissues: i.e. the retinaculum, and the fat pad. The rehabilitation professional can provide stabilisation through strengthening and neuromuscular control training, patellar taping techniques and knee braces.

For a review on exercise training for the patellofemoral joint, please read this article.

A reminder when creating an exercise programme for the adolescent patient population: "let's be realistic, let's be pragmatic, and let's incorporate lots of education in our treatment of adolescent patellofemoral pain."[1]

Resources[edit | edit source]

Clinical Resources:


Optional Additional Reading:

References[edit | edit source]

  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 1.22 Robertson, C. Patellofemoral Joint Programme. Adolescent Patellofemoral Pain. Physioplus. 2022.
  2. 2.0 2.1 2.2 2.3 Rathleff MS, Winiarski L, Krommes K, Graven-Nielsen T, Hölmich P, Olesen JL, Holden S, Thorborg K. Pain, sports participation, and physical function in adolescents with patellofemoral pain and Osgood-Schlatter disease: a matched cross-sectional study. Journal of orthopaedic & sports physical therapy. 2020 Mar;50(3):149-57.
  3. 3.0 3.1 3.2 3.3 3.4 Fick CN, Grant C, Sheehan FT. Patellofemoral pain in adolescents: understanding patellofemoral morphology and its relationship to maltracking. The American journal of sports medicine. 2020 Feb;48(2):341-50.
  4. 4.0 4.1 4.2 van Middelkoop M, van der Heijden RA, Bierma-Zeinstra SM. Characteristics and outcome of patellofemoral pain in adolescents: do they differ from adults?. journal of orthopaedic & sports physical therapy. 2017 Oct;47(10):801-5.
  5. Rathleff MS, Roos EM, Olesen JL, Rasmussen S. Exercise during school hours when added to patient education improves outcome for 2 years in adolescent patellofemoral pain: a cluster randomised trial. British journal of sports medicine. 2015 Mar 1;49(6):406-12.
  6. 6.0 6.1 6.2 Rathleff MS, Graven-Nielsen T, Hölmich P, Winiarski L, Krommes K, Holden S, Thorborg K. Activity modification and load management of adolescents with patellofemoral pain: a prospective intervention study including 151 adolescents.The American Journal of Sports Medicine. 2019 Jun;47(7):1629-37.
  7. 7.0 7.1 Smith JM, Varacallo M. 2019. Available at: https://www.ncbi.nlm.nih.gov/books/NBK441995/ (accessed 29/08/2022).
  8. Physiopedia. Sinding Larsen Johansson Syndrome. Available from: Sinding Larsen Johansson Syndrome#cite note-5 (accessed 31/08/2022).
  9. 9.0 9.1 Physiopedia. Osteochondritis Dissecans of the Knee. Available from: Osteochondritis Dissecans of the Knee#cite ref-Erickson et al 1-6 (accessed 01/09/2022).
  10. Behera TP, Kashyap D. Effect of Agility and Perturbation Training on Pain, Balance and Functional Ability in Subjects with Patellofemoral Pain Syndrome. International Journal of Health Sciences and Research. Vol.11; Issue: 7; July 2021.
  11. Physiopedia. Kinesiophobia. Available from: Kinesiophobia#cite note-1  (accessed 03/09/2022).
  12. 12.0 12.1 Huang J, Xu Y, Xuan R, Baker JS, Gu Y. A Mixed Comparison of Interventions for Kinesiophobia in Individuals With Musculoskeletal Pain: Systematic Review and Network Meta-Analysis. Frontiers in Psychology. 2022;13.
  13. YouTube. Graded Exposure to Painful Activities | Pain Science Physical Therapy. Available from: https://www.youtube.com/watch?v=p67qLOYL9cg [last accessed 04/09/2022]
  14. 14.0 14.1 Selhorst M, Fernandez-Fernandez A, Schmitt L, Hoehn J. Effect of a psychologically informed intervention to treat adolescents with patellofemoral pain: a randomized controlled trial. Arch Phys Med Rehabil. 2021;102(7):1267-73.