Activity Modification and Load Management of Adolescents With Patellofemoral Pain: A Prospective Intervention Study Including 151 Adolescents

Self-management including exercise, education and activity modification compared to usual care for adolescents with Osgood-Schlatter (the SOGOOD trial): protocol of a randomized controlled superiority trial

BACKGROUND

Osgood-Schlatter is the most frequent growth-related injury affecting about 10% of physically active adolescents. It can cause long-term pain and limitations in sports and physical activity, with potential sequela well into adulthood. The management of Osgood-Schlatter is very heterogeneous. Recent systematic reviews have found low level evidence for surgical intervention and injection therapies, and an absence of studies on conservative management. Recently, a novel self-management approach with exercise, education, and activity modification, demonstrated favorable outcomes for adolescents with patellofemoral pain and Osgood-Schlatter in prospective cohort studies.

AIM

The aim of this trial is to assess the effectiveness of the novel self-management approach compared to usual care in improving self-reported knee-related function in sport (measured using the KOOS-child 'Sport/play' subscale) after a 5-month period.

METHODS

This trial is a pragmatic, assessor-blinded, randomized controlled trial with a two-group parallel arm design, including participants aged 10-16 years diagnosed with Osgood-Schlatter. Participants will receive 3 months of treatment, consisting of either usual care or the self-management approach including exercise, education, and activity modification, followed by 2 months of self-management. Primary endpoint is the KOOS-child 'Sport/play' score at 5 months. This protocol details the planned methods and procedures.

DISCUSSION

The novel approach has already shown promise in previous cohort studies. This trial will potentially provide much-needed level 1 evidence for the effectiveness of the self-management approach, representing a crucial step towards addressing the long-term pain and limitations associated with Osgood-Schlatter.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT05174182. Prospectively registered December 30th 2021. Date of first recruitment: January 3rd 2022. Target sample size: 130 participants.

The effectiveness of customised 3D-printed insoles on perceived pain, comfort, and completion time among frequent Park Runners: Study protocol for a pragmatic randomised controlled trial (The ZOLES RCT)

BACKGROUND

Running, a popular recreational activity, often leads to the experience of pain and discomfort among participants impacting performance and participation longevity. The ZOLES trial evaluates customised 3D-printed insoles for reducing pain in frequent parkrunners aged 35 and over. An innovative process of foot-scanning and responses to questions relating to size, pain, discomfort, and previous medical conditions are combined leading to the production of personalised 3D-printed orthotics.

METHODS

The ZOLES trial is a pragmatic, outcome assessor blinded, randomised, controlled, superiority trial involving 200 recreational runners, randomised to receive either customised 3D-printed insoles (ZOLES) or to a "do-as-usual" control group. The study follows a robust protocol, ensuring adherence to established guidelines for clinical trials, and is based at St Mary's University, Twickenham, London. The primary outcome is change in running-related pain over a 10-week period, assessed using an 11-point Numeric Rating Scale. Secondary outcomes include overall pain and discomfort, running-related comfort, 5k-completion time, time-loss due to injuries, running exposure, and adherence to the intervention. A balanced-block randomisation process is stratified by sex and parkrun location, and an intention-to-treat analyses will be employed on all outcomes in the primary trial report. The trial includes a 52-week post-market surveillance to assess long-term effects of the customised insoles.

DISCUSSION

The ZOLES trial aims to provide insights into real-world applicability and effectiveness of customised 3D-printed insoles in reducing running-related pain and enhancing overall running experience. Despite the limitation of a subjective primary outcome measure without participant blinding, the methodological rigor, including external outcome assessment and data handling, we anticipate results that are academically credible and applicable in real-world settings The results of this trial may have important implications for runners, clinicians, and the sports footwear industry, as evidence for the use of individualised insoles to improve running experience and prevention of pain may become evident.

TRIAL REGISTRATION

The trial was pre-registered at ClinicalTrials.gov with the trial identifier NCT06034210 on September 4, 2023, and publicly posted on September 13, 2023 (https://clinicaltrials.gov/study/NCT06034210).

PROTOCOL VERSION

Version 1, September 27, 2023.

Exploring the pain and disability continuum in adolescents with non-traumatic anterior knee pain: a mediation analysis using individual participant data of prospective studies

OBJECTIVE

To use individual patient data (IPD) to investigate if the effect of pain on sports-related disability is mediated through physical (lower extremity isometric strength) or psychological (depression/anxiety and knee confidence) factors in adolescents with non-traumatic anterior knee pain.

METHODS

This study included four datasets from a previously harmonised IPD dataset. Prior to analysis, the protocol and analysis approach were predefined and published on Open Science Framework. Potential mediators were pre-sepcified as isometric knee and hip strengths, self-reported anxiety/depression and confidence in the knee, allmeasured at 12 weeks after baseline evaluation. Mediation analyses were undertaken using the CMAVerse package in RStudio using the regression-based approach to decompose the total effect of the exposure (pain at baseline evaluation) on the outcome (sports-related disability at 6 months) into the 'indirect effect' (the portion of the total effect acting through the mediators) and the 'direct effect'.

RESULTS

Two-hundred and seventy-nine adolescents with non-traumatic knee pain were included in the analysis. Median age was 13 (range 10-19), and 72% were women. Baseline pain was associated with sports-related disability at 6 months. There was no evidence of the association being mediated by any of the proposed mediators (total natural indirect effect for strength 0.01 (-1.14 to 1.80) and psychological factors 0.00 (-0.66 to 2.02)).

CONCLUSION

We found an effect of pain on sports-related disability at 6 months which appears to be independent of lower extremity muscle strength, or depression/anxiety and knee confidence in adolescents with non-traumatic anterior knee pain.

Comparing the effect of intermittent blood flow restriction training and high-load resistance training in patients with patellofemoral pain: study protocol for a randomised trial

BACKGROUND

Patellofemoral pain (PFP) syndrome is a common knee joint functional disorder. Blood flow restriction (BFR) training has shown promise in improving PFP; however, the effectiveness of intermittent BFR (iBFR) training remains uncertain. This study aims to compare the rehabilitative effects of iBFR combined with low-load resistance training and high-load resistance training in PFP patients and to assess the effectiveness of iBFR combined with low-load resistance training for improving PFP.

METHODS AND ANALYSIS

This randomised, patient-assessor blinded, controlled trial will include 42 eligible PFP patients randomly allocated to an intervention group (iBFR combined with low-load resistance training) or a control group (high-load resistance training) in a 1:1 ratio. Participants will receive interventions three times per week for 8 weeks and will be followed up for 24 weeks. The primary outcome measure is pain, and the secondary outcomes include self-reported function, quality of life, muscle strength and muscle thickness. Assessments will be conducted at baseline, 8 weeks and 24 weeks during follow-up. Intention-to-treat analysis will be performed.Collectively, we expect that the findings of this randomised clinical trial will contribute to understanding the potential benefits of iBFR training and provide insightful guidance for developing more effective treatment strategies for patients with PFP.

ETHICS AND DISSEMINATION

This study was approved by the Sports Science Experiment Ethics Committee of Beijing Sport University (2022274H). Written informed consent will be obtained from all participants. Trial results will be disseminated through peer-reviewed publications.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry (ChiCTR2300068281).

The Effect of a Psychologically Informed Video Series to Treat Adolescents With Patellofemoral Pain: A Randomized Controlled Trial

OBJECTIVE: To test whether a series of brief, psychologically informed educational videos added to physical therapy improved function among adolescents with patellofemoral pain. The secondary aims were to assess pain and psychological beliefs. DESIGN: A double-blinded randomized controlled trial. METHODS: Sixty-eight adolescents with patellofemoral pain were randomly assigned to view brief, psychologically informed videos (n = 34) or control videos (n = 34) in addition to usual care physical therapy. The psychologically informed videos targeted fear-avoidance beliefs, kinesiophobia, and pain catastrophizing. The control videos conveyed basic anatomy, biomedical factors, and lower extremity mechanics. Outcomes were assessed at baseline, 3 weeks, 6 weeks (primary end point), and 3 months. The primary outcome was change in the Anterior Knee Pain Scale. Secondary outcomes were changes in Numeric Pain-Rating Scale and psychological beliefs (Modified Fear-Avoidance Beliefs Questionnaire-Physical Activity, Tampa Kinesiophobia Scale-11, and Pain Catastrophizing Scale-Child). RESULTS: Adolescents in the psychologically informed group experienced significantly greater improvements in function (Anterior Knee Pain Scale mean difference = 8 points; 95% CI: 2.2, 13.2; P = .01) and pain (Numeric Pain-Rating Scale mean difference = 1.2 points; 95% CI: 0.1, 2.4; P = .04) at 6 weeks compared to the control group. The psychologically informed group had significantly greater reductions in psychological beliefs over time than the control group (P≤.001; partial η2 = 0.32). CONCLUSION: Incorporating psychologically informed education into physical therapy care improved function, pain, and psychological beliefs to a greater extent than the control group. J Orthop Sports Phys Ther 2023;53(10):1-9. Epub: 14 September 2023. doi:10.2519/jospt.2023.12041.

Lower extremity muscle volume in females with patellofemoral pain and its relationships to hip and knee torque: A cross-sectional study

OBJECTIVES

Compare lower extremity muscle volume in females with patellofemoral pain (PFP) to a cohort of pain-free females and investigate the relationship between thigh and hip muscle volume and torque.

DESIGN

Cross-sectional.

PARTICIPANTS

Twenty-one females, 13 with PFP and 8 pain-free controls.

MAIN OUTCOME MEASURES

We quantified normalized lower extremity muscle volume (cm3/kg*m) via magnetic resonance imaging and isometric hip and thigh torque (Nm/kg) via a multimodal dynamometer.

RESULTS

Versus pain-free individuals, females with PFP had smaller muscle volume of the anterior hip (P < 0.019; d = 0.97-2.42), deep external rotators (P < 0.006; d = 1.0-3.93), hamstrings (P < 0.009; d = 1.09-2.12), rectus femoris (P < 0.001; d = 1.79), and vastus intermedius (P < 0.001; d = 1.88). There was no difference in muscle volume of the gluteus maximus (P = 0.311; d = 0.22), gluteus medius (P = 0.087; d = 0.87), vastus lateralis (P = 0.22; d = 0.39), and vastus medialis (P = 0.47; d = 0.04). Gluteus maximus volume was moderately correlated to hip abduction torque (r = 0.60; P = 0.03). Vasti muscles and semitendinosus volume were moderately correlated to knee extension (r = 0.57-0.69; P < 0.05) and flexion (r = 0.66; P = 0.01) torque, respectively.

CONCLUSION

Females with PFP present with lesser thigh and hip muscle volumes, with variability in volumetric profiles across participants. Lower extremity knee extension and hip abduction strength are moderately associated with the vasti and gluteus maximus muscle volume, respectively.

Bone Health in Young Athletes: a Narrative Review of the Recent Literature

PURPOSE OF REVIEW

The aim of this review is to discuss the most recent published scientific evidence regarding bone health in the pediatric athlete.

RECENT FINDINGS

Pediatric athletes commonly suffer from overuse injuries to the physes and apophyses, as well as bone stress injuries, for which magnetic resonance imaging grading of the severity of injuries may be useful in guiding return to sport. Adolescent athletes, particularly those who train indoors and during the winter season, are at risk for vitamin D deficiency, which has important implications for bone mineral density. However, the relationship between vitamin D status and traumatic fracture risk is still unclear. While the female athlete triad is a well-established condition, the current work has led to the recognition of parallel pathophysiology in male athletes, referred to as the male athlete triad. Recent evidence suggests that transdermal 17β-estradiol treatment in amenorrhoeic female athletes is an effective adjunctive treatment to improve bone mineral density in treatment of the female athlete triad. Young athletes are at risk for musculoskeletal injuries unique to the growing skeleton. Optimizing nutritional intake, particularly related to adequate vitamin D intake and prevention of the athlete triad, is critical to optimize bone health in the young athlete.

Exploring User Visions for Modeling mHealth Apps Toward Supporting Patient-Parent-Clinician Collaboration and Shared Decision-making When Treating Adolescent Knee Pain in General Practice: Workshop Study

BACKGROUND

Long-standing knee pain is one of the most common reasons for adolescents (aged 10-19 years) to consult general practice. Generally, 1 in 2 adolescents will continue to experience pain after 2 years, but exercises and self-management education can improve the prognosis. However, adherence to exercises and self-management education interventions remains poor. Mobile health (mHealth) apps have the potential for supporting adolescents' self-management, enhancing treatment adherence, and fostering patient-centered approaches. However, it remains unclear how mHealth apps should be designed to act as tools for supporting individual and collaborative management of adolescents' knee pain in a general practice setting.

OBJECTIVE

The aim of the study was to extract design principles for designing mHealth core features, which were both sufficiently robust to support adolescents' everyday management of their knee pain and sufficiently flexible to act as enablers for enhancing patient-parent collaboration and shared decision-making.

METHODS

Overall, 3 future workshops were conducted with young adults with chronic knee pain since adolescence, parents, and general practitioners (GPs). Each workshop followed similar procedures, using case vignettes and design cards to stimulate discussions, shared construction of knowledge and elicit visions for mHealth designs. Young adults and parents were recruited via social media posts targeting individuals in Northern Jutland. GPs were recruited via email and cold calling. Data were transcribed and analyzed thematically using NVivo (QSR International) coding software. Extracted themes were synthesized in a matrix to map tensions in the collaborative space and inform a conceptual model for designing mHealth core-features to support individual and collaborative management of knee pain.

RESULTS

Overall, 38% (9/24) young adults with chronic knee pain since adolescence, 25% (6/24) parents, and 38% (9/24) GPs participated in the workshops. Data analysis revealed how adolescents, parents, and clinicians took on different roles within the collaborative space, with different tasks, challenges, and information needs. In total, 5 themes were identified: adolescents as explorers of pain and social rules; parents as supporters, advocates and enforcers of boundaries; and GPs as guides, gatekeepers, and navigators or systemic constraints described participants' roles; collaborative barriers and tensions referred to the contextual elements; and visions for an mHealth app identified beneficial core features. The synthesis informed a conceptual model, outlining 3 principles for consolidating mHealth core features as enablers for supporting role negotiation, limiting collaborative tensions, and facilitating shared decision-making.

CONCLUSIONS

An mHealth app for treating adolescents with knee pain should be designed to accommodate multiple users, enable them to shift between individual management decision-making, take charge, and engage in role negotiation to inform shared decision-making. We identified 3 silver-bullet principles for consolidating mHealth core features as enablers for negotiation by supporting patient-GP collaboration, supporting transitions, and cultivating the parent-GP alliance.

Quality of life in adolescents with longstanding non-traumatic knee pain: An analysis of 316 adolescents with Patellofemoral Pain and Osgood-Schlatter Disease

OBJECTIVES

To describe the Quality of Life (QoL) among adolescents with Patellofemoral Pain (PFP) and Osgood-Schlatter Disease (OSD) and investigate characteristics associated with QoL.

STUDY DESIGN

Cross-sectional.

PARTICIPANTS

316 adolescents with PFP or OSD.

MAIN OUTCOME MEASURES

QoL subscale of The Knee injury and Osteoarthritis Outcome Score (KOOS) and the EuroQol 5-dimensions (EQ-5D).

RESULTS

The KOOS-QoL was 51 ± 18, and the total index score for the EQ5D was 0.67 ± 0.21. KOOS-QoL subscale showed that 60% reported being aware of their knee problems daily or constantly, 38% reported severe to extreme lack of confidence in their knees, 28% reported severe to extreme difficulty with their knees, and 20% reported severely or totally modifying their lifestyle to avoid potentially damaging activities to their knee. EQ-5D showed that 79% experienced problems with everyday activities, 48% reported mobility problems, 17% felt worried, sad, or unhappy, and 7% reported problems looking after themselves.

CONCLUSIONS

Many adolescents with longstanding non-traumatic knee pain experience low QoL. More than half were aware of their knee problems at least daily, one in three reported a severe lack of confidence in their knee, and one in six felt worried, sad, or unhappy.

Exploring the barriers and facilitators for supporting adolescents with knee pains adherence to mobile health apps: A think-aloud study

Background

Mobile health (mHealth) applications have the potential to support adolescents' self-management of knee pain. However, ensuring adherence remains a barrier when designing mHealth concepts for adolescents.

Objective

This study aimed to explore barriers and facilitators for adhering to mHealth interventions to inform design principles.

Methods

Think-aloud tests were conducted with 12 adolescents (aged 12.5 years median) with knee pain, using a low-fidelity prototype. The prototype was informed by the authors previous work, rapid prototyping sessions with seven health professionals, and synthesis via the Behavioral Intervention Technology Model. The think-aloud tests were video recorded and analyzed thematically to identify design principles.

Results

The analysis based on user testing with adolescents with knee pain identified three themes: "user experience and feedback," "contextual challenges," and "new features" and nine subthemes. Adolescents were able to use mHealth behavioral features such as self-tracking, goal setting, education, and data visualization to capture and reflect on their knee pain developments, which facilitated use. However, adolescents struggle with timing interventions, breaking down management behaviors, and biases towards interventions were identified as internal threats to adherence. Competing activities, parental meddling, and privacy concerns were external adherence barriers. Twelve design principles were identified for integrating these insights into mHealth designs.

Conclusion

Participants' motivations for adherence were influenced by internal and external factors. While adolescents were able to use mHealth behavioral features to capture and reflect on knee pain developments, understanding how to accommodate adolescents' cognitive abilities, competing activities, and need for independence is quintessential to enhance adherence in everyday contexts.

Analgesic use in adolescents with patellofemoral pain or Osgood-Schlatter Disease: a secondary cross-sectional analysis of 323 subjects

OBJECTIVES

The prevalence of pain medication use for adolescent knee pain and factors associated with use are not well understood. This study aimed to determine the self-reported use of pain medication for knee pain and identify factors associated with use in adolescents (age 10-19) with longstanding knee symptoms.

METHODS

In this exploratory cross-sectional study, we performed a secondary analysis of data previously collected in 323 adolescents with longstanding knee pain. Factors associated with pain medication use were assessed using multivariable logistic regressions. Analyses were repeated with stratification by age, sex, sport participation frequency, knee pain duration, and knee pain intensity.

RESULTS

Among 323 adolescents (mean age 14.4 ± 2.5, 73% female), 84% had patellofemoral pain, (peri- or retro-patellar pain during loaded bending of the knee) and 16% had Osgood-Schlatter Disease (apophysitis with swelling and localized pain at the tibial tuberosity). Twenty-one percent (95% CI 16-25%) of adolescents reported pain medication use for their knee pain, with no difference in usage between those ≤ vs. > 15 years of age (21%, 95% CI 16-27% vs. 20%, 95% CI 13-29%). Adolescents with patellofemoral pain reported greater usage than their counterparts with Osgood-Schlatter Disease (22%, 95% CI 17-28% vs. 12%, 95% CI 4.5-24.3%). The most consistent factor associated with use was knee-related symptoms, observed in both the overall (OR 0.97, 95% CI 0.94-0.99) and stratified analyses (ORs ranged from 0.89 to 0.96).

CONCLUSIONS

Approximately one in five adolescents with longstanding knee pain reported pain medication use, particularly in adolescents with patellofemoral pain. Knee-related symptoms most consistently associated with the use of pain medications in this population. Future longitudinal studies with data collected at multiple time-points are needed to validate these findings.

IMPLICATIONS

Self-reported pain medication use is common in adolescents with longstanding knee pain, even though whether pharmacological therapy is the best pain management option at this young age is debatable. Reliance on pain medication at an early age could potentially hamper the development of healthy pain coping strategies and increase the risk of dependence and misuse later in life. Future studies should assess the safety, efficacy, and risks of long-term use of pain medications for adolescent knee pain.

Confidence and Knowledge of Athletic Trainers in Managing Patellofemoral Pain

CONTEXT

Patellofemoral pain (PFP) is prevalent and challenging to manage. Most patients with PFP are unsatisfied with their knee function at 6 months after treatment and report ongoing pain up to 16 years after diagnosis. The confidence and knowledge of athletic trainers (ATs) in providing evidence-based care to people with PFP is unknown.

OBJECTIVE

To investigate the confidence and knowledge of ATs in the diagnosis, risk factors, prognosis, and treatment with current evidence for PFP.

DESIGN

Cross-sectional study.

SETTING

Online survey.

PATIENT OR OTHER PARTICIPANTS

A random sample of 3000 ATs were invited to participate; 261 completed the survey (10% participation rate, 88% completion rate).

MAIN OUTCOME MEASURES(S)

We surveyed AT demographics, confidence in PFP management, and knowledge related to diagnosis, risk factors, prognosis, and treatment. The confidence and knowledge of ATs in managing PFP was assessed. Their beliefs about evidence were compared with the available evidence (ie, consensus statements, position statements, systematic reviews).

RESULTS

Of the ATs surveyed, 91% were confident that their management of PFP aligned with the current evidence, but only 59% were confident in identifying risk factors for PFP development. In addition, 91% to 92% of ATs agreed that quadriceps and hip muscle weakness were risk factors for PFP, which aligns with the current evidence for the former but not the latter. Moreover, 93% to 97% of ATs' responses related to therapeutic exercise aligned with current evidence. However, 35% to 48% supported the use of passive treatments, such as electrophysical agents and ultrasound, which did not align with the current evidence.

CONCLUSIONS

Most ATs were aware of supporting evidence for therapeutic exercise in PFP management and were confident providing it, creating a strong foundation for evidence-based care. However, varying levels of awareness of the evidence related to risk factors and passive treatments for PFP highlight the need for professional development initiatives to better align ATs' knowledge with the current evidence.

Optimizing Rehabilitation and Return to Sport in Athletes With Anterior Knee Pain Using a Biomechanical Perspective

Anterior knee pain represents one of the most common athletic knee conditions and arguably also one of the most complex. The patellofemoral joint is at the center of several forces, and alterations in any of these force vectors due to muscular imbalance, soft-tissue tightness or laxity, and altered functional movement patterns can all combine to create a painful anterior knee. While typically anterior knee pain is not a surgical entity, the orthopaedic surgeon with an understanding of these biomechanical intricacies is best positioned to provide comprehensive evidence-based care for the patient with anterior knee pain.

Level of Evidence

V, expert opinion.

The 45-second anterior knee pain provocation test: A quick test of knee pain and sporting function in 10-14-year-old adolescents with patellofemoral pain

OBJECTIVE

To test 1) if the 45-second Anterior Knee Pain Provocation Test (AKPP-test) could differentiate between adolescents with patellofemoral pain (PFP) and pain-free controls and; 2) whether improvements in the AKPP-test over 12 weeks were associated with improvements in self-reported knee function and pain.

DESIGN

Prospective cohort.

PATIENTS

151 with PFP and 50 pain-free controls (age 10-14 years).

OUTCOMES

The AKPP-test was performed at baseline, 4- and 12-week follow-up. Pain and function were collected using Knee Injury and Osteoarthritis Outcome Score (KOOS).

RESULTS

At baseline, the AKPP-test provoked pain to a median of 5 points (IQR: 3-7) on the 0-10 Numeric Pain Rating Scale in adolescents with PFP, compared to 0 (IQR 0-0) in controls. Higher pain during the AKPP-test was associated with worse KOOS-Sport/Rec (r = -0.33, P < 0.001), worse KOOS-Pain (r = -0.47, P < 0.001), and pain intensity (worst pain last 24 hours) (r = -0.39, P < 0.001) at baseline. Improvements in the AKPP-test over 12 weeks were associated with improvements in KOOS Pain (r = 0.48, P < 0.001) and KOOS Sport/Rec (r = 0.40, P < 0.001).

CONCLUSIONS

Improvements in the AKPP-test were associated with improvements in self-report knee pain and limitations in sports, suggesting the AKPP-test may be a clinically responsive test of knee pain and sporting function in adolescents with PFP.

Exploring the Pain in Patellofemoral Pain: A Systematic Review and Meta-Analysis Examining Signs of Central Sensitization

BACKGROUND

Patellofemoral pain (PFP) has high recurrence rates and minimal long-term treatment success. Central sensitization refers to dysfunctional pain modulation that occurs when nociceptive neurons become hyperresponsive. Researchers in this area of PFP have been increasingly productive in the past decade.

OBJECTIVE

To determine whether evidence supports manifestations of central sensitization in individuals with PFP.

DATA SOURCES

We searched MeSH terms for quantitative sensory testing (QST) pressure pain thresholds (PPTs), conditioned pain modulation (CPM), temporal summation, sensitization, hyperalgesia, and anterior knee pain or PFP in PubMed, SPORTDiscus, CINAHL, Academic Search Complete, and EBSCOhost.

STUDY SELECTION

Peer-reviewed studies that were written in English and published between 2005 and 2020 and investigated QST or pain mapping in a sample with PFP were included in this review.

DATA EXTRACTION

The initial search yielded 140 articles. After duplicates were removed, 78 abstracts were reviewed. The full text of 21 studies was examined, and we included 15 studies in our evaluation: 6 in the meta-analysis, 4 in the systematic review, and 5 in both the meta-analysis and systematic review.

DATA SYNTHESIS

A random-effects meta-analysis was conducted for 4 QST variables (local PPTs, remote PPTs, CPM, temporal summation). Strong evidence supported lower local and remote PPTs, impaired CPM, and facilitated temporal summation in individuals with PFP compared with pain-free individuals. Evidence for heat and cold pain thresholds was conflicting. Pain mapping demonstrated expanding pain patterns associated with long duration of PFP symptoms.

CONCLUSIONS

Signs of central sensitization were present in individuals with PFP, indicating altered pain modulation. The etiologic and treatment models of PFP should reflect the current body of evidence regarding central sensitization. Signs of central sensitization should be monitored clinically, and treatments with central effects should be considered as part of a multimodal plan of care.

Nearly 40% of adolescent athletes report anterior knee pain regardless of maturation status, age, sex or sport played

OBJECTIVE

To report point prevalence of anterior knee pain (AKP) in adolescent athletes by (1) maturation status, (2) chronological age, (3) sex, and (4) primary sport.

DESIGN

Cross-sectional.

METHODS

Male and female participants aged 11-15 years were recruited from specialised sports programs for basketball, volleyball, Australian Rules Football and tennis. Standing height, sitting height, and body mass were measured and used to calculate maturity status. Past injury history, self-reported physical activity, and Victorian Institute of Sport Assessment Questionnaire Patellar Tendon (VISA-P) questionnaires were completed. Anterior knee pain was defined as any pain experienced on the anterior surface of the knee and recorded using a visual analogue scale (VAS). A single leg decline squat (SLDS) was performed for provocation of AKP.

RESULTS

Two hundred and seventeen male and female adolescent athletes participated in this study. Twenty participants were excluded from data analysis. Point prevalence of AKP was 39% (N = 76). Average self-reported physical activity/week was 7.9 ± 4.1 h of their specialised sport and 2.0 ± 2.0 h of other physical activity/week. Maturation status, chronological age, sex nor primary sporting program was statistically significant in explaining the presence or absence of AKP.

CONCLUSION

Due to the right-skewed maturation sample, the authors cannot state conclusively that maturation status was not associated with AKP. Nearly 40% of this cohort reported AKP during a pain provocation test. The presence of AKP was not explained by maturation status, age, sex or primary sport program. Given the chronic nature of AKP and future morbidity reported, this high prevalence provides rationale for intervention or prevention studies targeting younger athletes.

Prognostic factors for adolescent knee pain: an individual participant data meta-analysis of 1281 patients

ABSTRACT

Adolescent knee pain has a propensity for chronicity, impacting physical activity and health into adulthood. The aim of this study is to investigate prognostic factors in adolescents with knee pain using individual participant data (IPD) meta-analysis. Studies were identified through a systematic search and a collaborative group. We included IPD from prospective studies of adolescents (age 10-19 years) with nontraumatic knee pain (13 studies and 1516 adolescents with 1281 unique participants). Primary outcomes were pain intensity and function (Knee Injury and Osteoarthritis Outcome Score "Sport/Rec" subscale). Primary endpoint was 12 months. Risk of bias was appraised with Quality in Prognosis Studies tool. Harmonised IPD was analysed by multilevel modelling. Fifty-one percent reported knee pain after 12-months. Lower baseline pain frequency was associated with lower pain intensity at 12 months ("less than weekly"; 12 (95% confidence interval [CI] 7-17) and "monthly"; 15 (95% CI 9-22) points lower on a 100-point pain scale, compared with "almost daily pain"). Other factors most strongly associated with 1-year pain prognosis were lower quality of life (30, 95% CI 19-42 points per unit change in the EQ5D index score), female sex (8 points, 95% CI 4-12 higher compared with males), and bilateral pain (7, 95% CI 1-13 points higher pain). Similar factors were associated with function. Body mass index, pain sensitivity, and knee strength were not associated with prognosis of pain or function. Adolescent knee pain is associated with clinically relevant long-term pain and functional deficits. Self-reported characteristics may help identify those at risk of poor prognosis.

Physical Therapist Management of Anterior Knee Pain

PURPOSE OF REVIEW

Anterior knee pain is a common musculoskeletal complaint among people of all ages and activity levels. Non-operative approaches with an emphasis on physical therapy management are the recommended initial course of care. The purpose of this review is to describe the current evidence for physical therapist management of anterior knee pain with consideration of biomechanical and psychosocial factors.

RECENT FINDINGS

The latest research suggests anterior knee pain is a combination of biomechanical, neuromuscular, behavioral, and psychological factors. Education strategies to improve the patient's understanding of the condition and manage pain are supported by research. Strong evidence continues to support the primary role of exercise therapy and load progression to achieve long-term improvements in pain and function. Preliminary studies suggest blood flow restriction therapy and movement retraining may be useful adjunct techniques but require further well-designed studies. Anterior knee pain includes multiple conditions with patellofemoral pain being the most common. An insidious onset is typical and often attributed to changes in activity and underlying neuromuscular impairments. A thorough clinical history and physical examination aim to identify the patient's pain beliefs and behaviors, movement faults, and muscle performance that will guide treatment recommendations. Successful physical therapist management involves a combination of individualized patient education, pain management, and load control and progression, with an emphasis on exercise therapy.

A Contemporary Approach to Patellofemoral Pain in Runners

Patellofemoral pain (PFP) is among the most common injuries in recreational runners. Current evidence does not identify alignment, muscle weakness, and patellar maltracking or a combination of these as causes of PFP. Rather than solely investigating biomechanics, we suggest a holistic approach to address the causes of PFP. Both external loads, such as changes in training parameters and biomechanics, and internal loads, such as sleep and psychological stress, should be considered. As for the management of runners with PFP, recent research suggested that various interventions can be considered to help symptoms, even if these interventions target biomechanical factors that may not have caused the injury in the first place. In this Current Concepts article, we describe how the latest evidence on education about training modifications, strengthening exercises, gait and footwear modifications, and psychosocial factors can be applied when treating runners with PFP. The importance of maintaining relative homeostasis between load and capacity will be emphasized. Recommendations for temporary or longer-term interventions will be discussed. A holistic, evidence-based approach should consist of a graded exposure to load, including movement, exercise, and running, while considering the capacity of the individual, including sleep and psychosocial factors. Cost, accessibility, and the personal preferences of patients should also be considered.

Novel Stepped Care Approach to Provide Education and Exercise Therapy for Patellofemoral Pain: Feasibility Study

Background

Patellofemoral pain (PFP) impairs joint- and health-related quality of life and may be associated with knee osteoarthritis. We developed a novel, 2-phase, stepped-care approach for PFP, combining (1) self-directed web-based education and exercise therapy with (2) physiotherapist-supported education and exercise therapy. Physiotherapy sessions can be provided using 2 different modalities: face-to-face and telerehabilitation.

Objective

This study aims to (1) determine the feasibility of our stepped-care approach, (2) explore patient-reported outcomes following self-directed web-based education and exercise therapy in people with PFP (phase 1), and (3) estimate the differences in treatment effects between face-to-face and telerehabilitation to support further education and exercise therapy (phase 2) in those who had not completely recovered following self-directed care.

Methods

Phase 1 involved 6 weeks of self-directed web-based education and exercise therapy. Phase 2 involved random allocation to a further 12 weeks of physiotherapist-led (up to 8 sessions) education and exercise therapy delivered face-to-face or via telerehabilitation to participants who did not rate themselves as completely recovered following phase 1. Feasibility indicators of process, adherence, and participant retention were collected as primary outcomes alongside patient-reported outcomes on Global Rating of Change and knee pain, disability, knee-related quality of life, pain catastrophism, kinesiophobia, and knee self-efficacy. All participants were assessed at baseline, 6 weeks, and 18 weeks.

Results

A total of 71 participants were screened to identify 35 participants with PFP to enter the study. Overall, 100% (35/35) and 88% (31/35) of the participants were followed up with at 6 and 18 weeks, respectively. In phase 1 of the study, participants accessed the My Knee Cap website for an average of 6 (7.5) days and performed the exercises for an average of 2.5 (3.6) times per week. A total of 20% (7/35) of the participants reported that they had completely recovered at 6 weeks. Furthermore, 93% (26/28) of the participants who were followed up and had not completely recovered at 6 weeks agreed to be enrolled in phase 2. No statistically significant differences were found between the face-to-face and telerehabilitation groups for any outcome. The novel stepped-care approach was associated with marked improvement or complete recovery in 40% (14/35) of the participants following phase 1 and 71% (25/35) of the participants following phase 2.

Conclusions

Self-directed web-based education and exercise therapy for people with PFP is feasible, as noted by the high rate of participant retention and home exercise adherence achieved in this study. Furthermore, 20% (7/35) of people reported complete recovery at 6 weeks. Both face-to-face and telerehabilitation physiotherapy should be considered for those continuing to seek care, as there is no difference in outcomes between these delivery modes. Determining the efficacy of the stepped-care model may help guide more efficient health care for PFP.

Patient Education for Patellofemoral Pain: A Systematic Review

OBJECTIVE

To evaluate the effect of education interventions compared with any type of comparator on managing patellofemoral pain (PFP).

DESIGN

Intervention systematic review. PROSPERO identifier: CRD42018088671.

LITERATURE SEARCH

MEDLINE, Embase, CINAHL, and Web of Science were searched for studies evaluating the effect of education on clinical and functional outcomes in people with PFP.

STUDY SELECTION CRITERIA

Two reviewers independently assessed studies for inclusion and quality. We included randomized controlled trials on PFP where at least 1 group received an education intervention (in isolation or in combination with other interventions).

DATA SYNTHESIS

Available data were synthesized via meta-analysis where possible; data that were not appropriate for pooling were synthesized qualitatively. Interpretation was guided by the Grading of Recommendations Assessment, Development and Evaluation approach.

RESULTS

Nine trials were identified. Low-credibility evidence indicated that health education material alone was inferior to exercise therapy for pain and function outcomes. Low- and very low-credibility evidence indicated that health professional-delivered education alone produced outcomes similar to those of exercise therapy combined with health professional-delivered education for pain and function, respectively.

CONCLUSION

Health professional-delivered education may produce similar outcomes in pain and function compared to exercise therapy plus health professional-delivered education in people with PFP. J Orthop Sports Phys Ther 2020;50(7):388-396. Epub 29 Apr 2020. doi:10.2519/jospt.2020.9400.

Activity Modification and Knee Strengthening for Osgood-Schlatter Disease: A Prospective Cohort Study

Background:

Osgood-Schlatter disease (OSD) affects 1 in 10 adolescents. There is a lack of evidence-based interventions, and passive approaches (eg, rest and avoidance of painful activities) are often prescribed.

Purpose:

To investigate an intervention consisting of education on activity modification and knee-strengthening exercises designed for adolescents with OSD.

Study Design:

Case series; Level of evidence, 4.

Methods:

This study included 51 adolescents (51% female; age range, 10-14 years) with OSD. The 12-week intervention consisted of an activity ladder designed to manage patellar tendon loading and pain, knee-strengthening exercises, and a gradual return to sport. The primary outcome was the global reporting of change at 12 weeks, evaluated with a 7-point Likert scale (successful outcome was considered “much improved” or “improved”). Additional endpoints were at 4, 8, 26, and 52 weeks. Secondary outcomes included the Knee injury and Osteoarthritis Outcome Score (KOOS), objective strength, and jump performance.

Results:

Adolescents reported a mean pain duration of 21 months at enrollment. After 12 weeks, 80% reported a successful outcome, which increased to 90% at 12 months. At 12 weeks, 16% returned to playing sport, which increased to 69% at 12 months. The KOOS subscores of Pain, Activities of Daily Living, Sport and Recreation, and Quality of Life improved significantly (7-20 points), and there were improvements in knee extension strength (32%; P < .001), hip abduction strength (24%; P < .001), and jumping for distance (14%; P < .001) and height (19%; P < .001) at 12 weeks.

Conclusion:

An intervention consisting of activity modification, pain monitoring, progressive strengthening, and a return-to-sport paradigm was associated with improved self-reported outcomes, hip and knee muscle strength, and jumping performance. This approach may offer an alternative to passive approaches such as rest or wait-and-see, often prescribed for adolescents with OSD.

Registration:

NCT02799394 (ClinicalTrials.gov identifier)

Pain, Sports Participation, and Physical Function in Adolescents With Patellofemoral Pain and Osgood-Schlatter Disease: A Matched Cross-sectional Study

OBJECTIVE

To compare pain, physical activity, quality of life, strength, and knee function in adolescents with patellofemoral pain (PFP) and Osgood-Schlatter disease (OSD) to those in pain-free controls.

DESIGN

Cross-sectional study.

METHODS

Self-report questionnaires were used to describe pain, physical activity, knee function, and quality of life in participants with PFP (n = 151) or OSD (n = 51) and in pain-free controls (n = 50) between 10 and 14 years of age. Hip and knee strength were measured by handheld dynamometry. Physical activity levels were measured using wearable accelerometers.

RESULTS

Adolescents were highly active (accumulating greater than 120 minutes of vigorous physical activity per day), with no differences between the OSD, PFP, and control groups. Adolescents with PFP or OSD scored 22 to 56 points lower (P<.001) on the Knee injury and Osteoarthritis Outcome Score subscales compared with controls, with the lowest scores on the "sport and recreation" and "quality of life" subscales. Adolescents with OSD had lower knee extension strength compared to controls (P<.05; effect size, 1.25). Adolescents with PFP had lower hip extension strength compared to controls (P<.05; effect size, 0.73).

CONCLUSION

Adolescents with PFP or OSD had high physical activity levels, despite reporting long-standing knee pain and impaired knee function that impacted on their sports participation and quality of life. Clinicians treating adolescents with PFP or OSD may use these findings to target treatment to the most common deficits to restore sports-related function and sports participation. J Orthop Sports Phys Ther 2020;50(3):149-157. Epub 6 Jan 2020. doi:10.2519/jospt.2020.8770.

Osgood-Schlatter disease: a 2020 update of a common knee condition in children

PURPOSE OF REVIEW

Osgood-Schlatter disease (OSD) is one of the most common causes for anterior knee pain in children and adolescents resulting from a traction apophysitis of the tibial tubercle. While a peak in boys aged 12-15 years old was well documented, there seems to be no difference in sex distribution nowadays. This may result from increased participation of young females in high-impact sports. This review provides an up-to-date account on contemporary prophylaxis as well as diagnostic and therapeutic approaches.

RECENT FINDINGS

Numerous studies have examined risk factors for OSD. These include body weight, muscle tightness, muscle weakness during knee extension and flexibility of hamstring muscles. In particular, shortening of the rectus femoris may substantially alter biomechanical functions of the knee. Conservative management remains successful in over 90% of patients. However, if disabling symptoms and pain persistent after physeal closure, operative treatment may be necessary.

SUMMARY

OSD is a mostly self-limiting apophysitis of the tibial tubercle and the adjacent patella tendon in young active patients with open physis. Prevention strategies include quadriceps and hamstring stretching and therefore should be implemented in everyday practice routines for children who partake in regular sports activities.

Predictors of Pain, Function, and Change in Patellofemoral Pain

BACKGROUND

Identification of factors predictive of outcome and change is important to improve treatment for patellofemoral pain (PFP). Few studies have examined the predictive value of psychological factors in PFP, although they have been reported to be important predictors in other musculoskeletal pain conditions.

PURPOSE

To evaluate predictors of pain, function, and change 1 year after an exercise-based intervention in PFP.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

In sum, 112 patients were recruited to a randomized controlled trial; 98 attended 1-year follow-up. There were no between-group differences in the trial; thus, the material was analyzed as 1 cohort. Nine baseline factors-sex, bilateral pain, worst pain, pain duration, Anterior Knee Pain Scale (AKPS), kinesiophobia, anxiety and depression, self-efficacy, and number of pain sites throughout the body-were investigated for their predictive ability on outcome at 1 year (AKPS, worst pain) and for change at 1 year (global change score, change in AKPS, and change in worst pain). Multivariable linear regression models with stepwise backward removal method were used to find predictors of poor outcome.

RESULTS

Number of pain sites at baseline was a significant predictor of worse outcome for AKPS (B = -2.7; 95% CI, -4.0 to -1.3; P < .01), worst pain (B = 0.5; 95% CI, 0.2-0.8; P < .01), global change (B = -0.8; 95% CI, -1.2 to -0.5; P < .01), change in AKPS (B = -2.7; 95% CI, -4.0 to -1.3; P < .01), and change in worst pain (B = 0.5, 95% CI, 0.2-0.8; P < .01) at 1 year. Baseline scores for AKPS and worst pain predicted respective 1-year levels and change scores (P < .01). Lower self-efficacy and male sex predicted less global change (P < .01). Longer pain duration predicted final score and change score for worst pain (P < .01). The predictive models had reasonable fit with adjusted R² from 0.22 to 0.35.

CONCLUSION

Higher number of pain sites throughout the body was a consistent predictor of poor outcome and less change at 1 year. Baseline levels for AKPS and worst pain predicted respective final scores and change scores.

REGISTRATION

NCT02114294 ( ClinicalTrials.gov identifier).