Definition and research guide
This page combines a MeSH definition, publication statistics and selected research abstracts. It is a starting point for reading the literature, not a medical textbook or a systematic evidence review.
Content available: 4 complete abstracts (960 words), 10 references. Full article text is not stored or reproduced here; follow the PMID, DOI or PMC links to read the original sources and their access terms.
Definition
A syndrome characterized by retropatellar or peripatellar PAIN resulting from physical and biochemical changes in the patellofemoral joint. The pain is most prominent when ascending or descending stairs, squatting, or sitting with flexed knees. There is a lack of consensus on the etiology and treatment. The syndrome is often confused with (or accompanied by) chondromalacia patellae, the latter describing a pathological condition of the cartilage and not a syndrome.
Definition: NLM Medical Subject Headings (MeSH) scope note (Public domain (U.S. National Library of Medicine); attribution requested). View the MeSH record.
Also known as: Pain Syndrome, Patellofemoral; Anterior Knee Pain Syndrome; Patellofemoral Syndrome; Patellofemoral Pain; Pain, Patellofemoral; Patellofemoral Pains.
Where it fits in the MeSH classification
- Broader topics
- Joint Diseases
- See also
- Chondromalacia Patellae
Related concepts
- Chondromalacia Patellae
- Cartilage
Research landscape
PubMed indexes 1,439 records tagged with the MeSH heading “Patellofemoral Pain Syndrome” (counts retrieved 2026-11-04). 553 of them (38.4%) were published from 2020 onward, and the busiest period so far is 2010-2019 with 685 records.
Reviews account for 258 records (17.9%) and meta-analyses for 73. Randomized controlled trials number 216 (15.0%) as a share of all records on the topic. Randomized trials make up a comparatively large share of this literature, which means many treatment questions have been tested directly.
Show the data
| Period | Records |
|---|---|
| through 1999 | 0 |
| 2000-2009 | 229 |
| 2010-2019 | 685 |
| 2020 onward | 553 |
Publication-type chart data
| Type | Records | Share |
|---|---|---|
| Reviews | 258 | 17.9% |
| Meta-analyses | 73 | 5.1% |
| Randomized controlled trials | 216 | 15.0% |
Method: PubMed query "Patellofemoral Pain Syndrome"[MeSH Terms] with publication-type and date filters, retrieved 2026-11-04.
Reading the evidence in bones, joints, muscles and skin
Joint, bone, muscle and skin conditions are often judged by pain scores, function questionnaires, imaging or photographs, and symptoms can fluctuate, so placebo response and natural improvement matter. Imaging changes are common in people without symptoms. Nothing on this page is advice about treatment. Check how outcomes were measured, whether the comparison group received a placebo or usual care, and how long the benefit lasted.
Evidence from open-access studies
These open-access studies come from PubMed’s best-match results for this heading (papers whose main topic it is), ranked here by citation count, with one recent addition. Each abstract is reproduced in full under its recorded open licence so that you can read the authors’ own words. They illustrate the literature; they are not a systematic summary of it. Citation counts measure attention, not reliability or clinical benefit.
| Study / authors | Year | Source label / design | Europe PMC citations | Licence / source |
|---|---|---|---|---|
| Patellofemoral pain syndrome | 2014 | Review article Design not recorded in structured metadata | 156 | cc by PMID 24221245 · DOI · PMC4169618 |
| Reliability of measures of impairments associated with patellofemoral pain syndrome | 2006 | Research article Design not recorded in structured metadata | 150 | cc by PMID 16579850 · DOI · PMC1557500 |
| The experience of living with patellofemoral pain-loss, confusion and fear-avoidance: a UK qualitative study | 2018 | Research article Design not recorded in structured metadata | 69 | cc by PMID 29362256 · DOI · PMC5786111 |
| Patellofemoral Pain After Knee Trauma: Exploring Clinical, Biomechanical, and Muscle Strength Variables | 2026 | Research article Design not recorded in structured metadata | 0 | cc by PMID 41983653 · DOI · PMC13081765 |
Patellofemoral pain syndrome [1]
Abstract reading summary — source excerpts
- Opening excerpt
- UnlabelledThe patellofemoral pain syndrome (PFPS) is a possible cause for anterior knee pain, which predominantly affects young female patients without any structural changes such as increased Q-angle or significant chondral damage.
- Closing excerpt
- Level of evidenceV.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (204 words)
UnlabelledThe patellofemoral pain syndrome (PFPS) is a possible cause for anterior knee pain, which predominantly affects young female patients without any structural changes such as increased Q-angle or significant chondral damage. This literature review has shown that PFPS development is probably multifactorial with various functional disorders of the lower extremity. Biomechanical studies described patellar maltracking and dynamic valgus in PFPS patients (functional malalignment). Causes for the dynamic valgus may be decreased strength of the hip abductors or abnormal rear-foot eversion with pes pronatus valgus. PFPS is further associated with vastus medialis/vastus lateralis dysbalance, hamstring tightness or iliotibial tract tightness. The literature provides evidence for a multimodal non-operative therapy concept with short-term use of NSAIDs, short-term use of a medially directed tape and exercise programmes with the inclusion of the lower extremity, and hip and trunk muscles. There is also evidence for the use of patellar braces and foot orthosis. A randomized controlled trial has shown that arthroscopy is not the treatment of choice for treatment of PFPS without any structural changes. Patients with anterior knee pain have to be examined carefully with regard to functional causes for a PFPS. The treatment of PFPS patients is non-operative and should address the functional causes.Level of evidenceV.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 24221245 · DOI · PMC4169618
Reliability of measures of impairments associated with patellofemoral pain syndrome [2]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundThe reliability and measurement error of several impairment measures used during the clinical examination of patients with patellofemoral pain syndrome (PFPS) has not been established.
- Closing excerpt
- Further investigation is needed to test if these impairment measurements are related to physical function and whether or not they are useful for decision-making.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (240 words)
BackgroundThe reliability and measurement error of several impairment measures used during the clinical examination of patients with patellofemoral pain syndrome (PFPS) has not been established. The purpose was to determine the inter-tester reliability and measurement error of measures of impairments associated with PFPS in patients with PFPS.MethodsA single group repeated measures design was used. Two pairs of physical therapists participated in data collection. Examiners were blinded to each others' measurements.ResultsThirty patients (age 29 +/- 8; 17 female) with PFPS participated in this study. Inter-tester reliability coefficients were substantial for measures of hamstrings, quadriceps, plantarflexors, and ITB/TFL complex length, hip abductors strength, and foot pronation (ICCs from .85 to .97); moderate for measures of Q-angle, tibial torsion, hip external rotation strength, lateral retinacular tightness, and quality of movement during a step down task (ICCs from .67 to .79); and poor for femoral anteversion (ICC of .45). Standard error of measurement (SEM) for measures of muscle length ranged from 1.6 degrees to 4.3 degrees. SEM for Q-angle, tibial torsion, and femoral anteversion were 2.4 degrees, 2.9 degrees, and 4.5 degrees respectively. SEM for foot pronation was 1 mm. SEM for measures of muscle strength was 1.8 Kg for abduction and 2.4 Kg for external rotation.ConclusionSeveral of the impairments associated with PFPS had sufficient reliability and low measurement error. Further investigation is needed to test if these impairment measurements are related to physical function and whether or not they are useful for decision-making.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 16579850 · DOI · PMC1557500
The experience of living with patellofemoral pain-loss, confusion and fear-avoidance: a UK qualitative study [3]
Abstract reading summary — source excerpts
- Opening excerpt
- ObjectivesTo investigate the experience of living with patellofemoral pain (PFP).
- Closing excerpt
- Trial registration numberISRCTN35272486; Pre-results.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (267 words)
ObjectivesTo investigate the experience of living with patellofemoral pain (PFP).DesignQualitative study design using semistructured interviews and analysed thematically using the guidelines set out by Braun and Clarke.SettingA National Health Service physiotherapy clinic within a large UK teaching hospital.ParticipantsA convenience sample of 10 participants, aged between 18 and 40 years, with a diagnosis of PFP and on a physiotherapy waiting list, prior to starting physiotherapy.ResultsParticipants offered rich and detailed accounts of the impact and lived experience of PFP, including loss of physical and functional ability; loss of self-identity; pain-related confusion and difficulty making sense of their pain; pain-related fear, including fear-avoidance and 'damage' beliefs; inappropriate coping strategies and fear of the future. The five major themes that emerged from the data were: (1) impact on self; (2) uncertainty, confusion and sense making; (3) exercise and activity beliefs; (4) behavioural coping strategies and (5) expectations of the future.ConclusionsThese findings offer an insight into the lived experience of individuals with PFP. Previous literature has focused on pain and biomechanics, rather than the individual experience, attached meanings and any wider context within a sociocultural perspective. Our findings suggest that future research is warranted into biopsychosocial targeted interventions aimed at the beliefs and pain-related fear for people with PFP. The current consensus that best-evidence treatments consisting of hip and knee strengthening may not be adequate to address the fears and beliefs identified in the current study. Further qualitative research may be warranted on the impact and interpretation of medical terminology commonly used with this patient group, for example, 'weakness' and 'patellar mal-tracking' and its impact and interpretation by patients.Trial registration numberISRCTN35272486; Pre-results.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 29362256 · DOI · PMC5786111
Patellofemoral Pain After Knee Trauma: Exploring Clinical, Biomechanical, and Muscle Strength Variables [4]
Abstract reading summary — source excerpts
- Opening excerpt
- It remains unclear whether people with traumatic-onset patellofemoral pain (PFP_T) present with the same physical and non-physical changes as people with gradual-onset patellofemoral pain (PFP_A).
- Closing excerpt
- , landing biomechanics and muscle strength) were evident only in comparison with CTRL_T, who also differed clinically and mechanically from CTRL_A.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (249 words)
It remains unclear whether people with traumatic-onset patellofemoral pain (PFP_T) present with the same physical and non-physical changes as people with gradual-onset patellofemoral pain (PFP_A). In this cross-sectional study, we aimed to compare clinical, biomechanical and muscle strength outcomes between people with PFP_T, people with PFP_A, pain-free controls with a history of knee trauma (CTRL_T), and pain-free controls without a history of knee trauma (CTRL_A). Clinical variables included pain-related characteristics, time since knee trauma, kinesiophobia, and functional capacity (e.g., self-reported, objective). We captured kinematics and kinetics during a single-leg landing task, and maximal isometric torque of the knee extensors and flexors, and the hip abductors using an isokinetic dynamometer. We performed between-group comparisons using generalized linear models and independent t-tests. The PFP_T group reported higher pain, greater kinesiophobia, and lower self-reported function compared with the PFP_A group. The PFP_T group also demonstrated greater peak trunk flexion, greater peak hip flexion, and a lower knee contribution to the total support moment (TSM) compared with the PFP_A group. Both the PFP_T and PFP_A groups demonstrated reduced isometric peak torque of the knee extensors compared with the CTRL_T group. The CTRL_T group demonstrated higher peak hip flexion, lower knee contribution to TSM, and greater patellofemoral joint stress compared with CTRL_A. People with PFP_T demonstrated a worse clinical profile and a more hip-dominant landing strategy compared with those with PFP_A. Most impairments (e.g., landing biomechanics and muscle strength) were evident only in comparison with CTRL_T, who also differed clinically and mechanically from CTRL_A.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 41983653 · DOI · PMC13081765
Key reviews and meta-analyses
The most cited review-type papers among PubMed’s best-match results for this heading, listed with bibliographic details only. Follow the links for the full text and access terms.
- Research article 2016 Patellofemoral pain consensus statement from the 4th International Patellofemoral Pain Research Retreat, Manchester. Part 1: Terminology, definitions, clinical examination, natural history, patellofemoral osteoarthritis and patient-reported outcome measures [5]
- Research article Quadriceps activation following knee injuries: a systematic review [6]
- Research article Patellofemoral Pain [7]
- Research article 2018 Consensus statement on exercise therapy and physical interventions (orthoses, taping and manual therapy) to treat patellofemoral pain: recommendations from the 5th International Patellofemoral Pain Research Retreat, Gold Coast, Australia, 2017 [8]
- Research article Evidence-based framework for a pathomechanical model of patellofemoral pain: 2017 patellofemoral pain consensus statement from the 4th International Patellofemoral Pain Research Retreat, Manchester, UK: part 3 [9]
- Research article 2016 Patellofemoral pain consensus statement from the 4th International Patellofemoral Pain Research Retreat, Manchester. Part 2: recommended physical interventions (exercise, taping, bracing, foot orthoses and combined interventions) [10]
References
- Petersen W, Ellermann A, Gösele-Koppenburg A, Best R, Rembitzki IV, Brüggemann GP, et al.. Patellofemoral pain syndrome. . 2014. PMID 24221245 · DOI · PMC4169618
- Piva SR, Fitzgerald K, Irrgang JJ, Jones S, Hando BR, Browder DA, et al.. Reliability of measures of impairments associated with patellofemoral pain syndrome. . 2006. PMID 16579850 · DOI · PMC1557500
- Smith BE, Moffatt F, Hendrick P, Bateman M, Rathleff MS, Selfe J, et al.. The experience of living with patellofemoral pain-loss, confusion and fear-avoidance: a UK qualitative study. . 2018. PMID 29362256 · DOI · PMC5786111
- Dos Santos Lopes H, Waiteman MC, Serrão FV, Van Cant J, Neal B, Briani RV, et al.. Patellofemoral Pain After Knee Trauma: Exploring Clinical, Biomechanical, and Muscle Strength Variables. . 2026. PMID 41983653 · DOI · PMC13081765
- Crossley KM, Stefanik JJ, Selfe J, Collins NJ, Davis IS, Powers CM, et al.. 2016 Patellofemoral pain consensus statement from the 4th International Patellofemoral Pain Research Retreat, Manchester. Part 1: Terminology, definitions, clinical examination, natural history, patellofemoral osteoarthritis and patient-reported outcome measures. Br J Sports Med. 2016. PMID 27343241 · DOI · PMC4975817
- Hart JM, Pietrosimone B, Hertel J, Ingersoll CD. Quadriceps activation following knee injuries: a systematic review. J Athl Train. 2010. PMID 20064053 · DOI · PMC2808760
- Willy RW, Hoglund LT, Barton CJ, Bolgla LA, Scalzitti DA, Logerstedt DS, et al.. Patellofemoral Pain. J Orthop Sports Phys Ther. 2019. PMID 31475628 · DOI
- Collins NJ, Barton CJ, van Middelkoop M, Callaghan MJ, Rathleff MS, Vicenzino BT, et al.. 2018 Consensus statement on exercise therapy and physical interventions (orthoses, taping and manual therapy) to treat patellofemoral pain: recommendations from the 5th International Patellofemoral Pain Research Retreat, Gold Coast, Australia, 2017. Br J Sports Med. 2018. PMID 29925502 · DOI
- Powers CM, Witvrouw E, Davis IS, Crossley KM. Evidence-based framework for a pathomechanical model of patellofemoral pain: 2017 patellofemoral pain consensus statement from the 4th International Patellofemoral Pain Research Retreat, Manchester, UK: part 3. Br J Sports Med. 2017. PMID 29109118 · DOI
- Crossley KM, van Middelkoop M, Callaghan MJ, Collins NJ, Rathleff MS, Barton CJ. 2016 Patellofemoral pain consensus statement from the 4th International Patellofemoral Pain Research Retreat, Manchester. Part 2: recommended physical interventions (exercise, taping, bracing, foot orthoses and combined interventions). Br J Sports Med. 2016. PMID 27247098 · DOI · PMC4975825
About this article
- Sources
- NLM Medical Subject Headings (definition, synonyms); NCBI PubMed (counts, identifiers); Europe PMC (open-access abstracts and citation counts).
- Verification
- Every reference was resolved against PubMed on 2026-11-04; title, year and DOI matched.
- Review state
- automated source verified; no human expert review has been recorded yet.
- Version
- 1, last updated 2026-11-04.
See how EvidenceLib is built. Spotted an error? Email support@evidencehelix.com.
Evidence strength
EvidenceHelix's computed view of the study designs behind this topic: how common meta-analyses, randomized trials and reviews are, how recent the literature is, and a plain-language reading. It describes the design mix of the literature. It is not a quality appraisal of any study, and it is not medical advice.