Early intervention for adolescents with patellofemoral pain syndrome--a pragmatic cluster randomised controlled trial

Effects of high frequency strengthening on pain sensitivity and function in female runners with chronic patellofemoral pain

OBJECTIVE

To investigate the effects of a high frequency strengthening program on function, pain, and pain sensitization in female runners with chronic patellofemoral pain (PFP).

DESIGN

Cross-sectional study.

SETTING

University laboratory.

PARTICIPANTS

Thirty female runners (mean age 32 ± 8.1 years) with chronic PFP completed an 8-week home strengthening program.

MAIN OUTCOME MEASURES

Variables assessed at baseline, 8-weeks, and 12 weeks included single leg step down test (SLSD), pain, Anterior Knee Pain Scale (AKPS), University of Wisconsin Running Injury and Recovery Index (UWRI), and quantitative sensory testing.

RESULTS

There was large and statistically significant improvement at 8 and 12 weeks for average knee pain (ηp2 = 0.334, p < 0.001), worst knee pain (ηp2 = 0.351, p < 0.001), SLSD (ηp2 = 0.161, p = 0.001), AKPS (ηp2 = 0.463, p < 0.001), and UWRI (ηp2 = 0.366, p < 0.001). A medium to large effect and statistically significant improvement in pressure pain threshold testing was found for all local and remote structures (ηp2 range, 0.110 to 0.293, range p < 0.001 to p = 0.009) at 8 and 12 weeks.

CONCLUSIONS

There was a significant decrease in local and remote hyperalgesia via mechanical and thermal pain sensitivity testing in female runners with chronic PFP. There was a large effect and significant improvement in self-reported pain and function.

Effects of McConnell and Kinesio Tapings on Pain and Gait Parameters during Stair Ambulation in Patients with Patellofemoral Pain Syndrome

Background and Objectives: The purpose of this study was to investigate the effects of McConnell and Kinesio tapings on knee pain and gait parameters during stair ambulation in patients with patellofemoral pain syndrome (PFPS). Materials and Methods: We selected 52 young adults suffering from anterior knee pain due to PFPS to participate. Then, we randomly assigned 26 patients to either the McConnell or the Kinesio taping groups. We measured their knee pain and gait parameters during stair ambulation before and after the interventions. For the measured data, we performed a paired t-test to evaluate the amount of change before and after the intervention within the groups and an independent t-test to compare the groups. Results: From the comparison within the groups, we found a significant difference in both groups in the anterior knee pain scale score (p < 0.05) and a significant difference between the groups as well (p < 0.05). As a result of the analysis of the gait parameters while ascending stairs in the comparison within the groups, both groups showed significant differences in all gait variables, except for the double-support stance (p < 0.05), and we found significant differences in all gait variables, except for the double-support stance, in the comparison between the groups (p < 0.05). Regarding the gait variables during stair descent in the comparison within the groups (p < 0.05), both groups showed significant differences in all of the gait variables; we noted significant differences in the double-support stance, step length, velocity, and cadence in the comparison between the groups (p < 0.05). Conclusions: The McConnell and Kinesio tapings were effective in improving knee pain and gait parameters during ambulation in patients with PFPS, but we found that the McConnell taping had a significant impact on pain reduction during stair ambulation, resulting in further improvement in the gait variables.

Care-seeking behaviour of adolescents with patellofemoral pain: a retrospective cohort study

AIM

The aim of this study was to assess the care-seeking behaviour among adolescents with patellofemoral pain (PFP).

METHODS

This retrospective study included data on 121 adolescents with PFP enrolled in a randomized controlled trial. A questionnaire was sent to the general practitioner (GP) of each adolescent, assessing information on the consultation dates for knee pain, potential diagnoses, and treatment provided.

RESULTS

106/121 adolescents had been in contact with their GP, and 95 medical records of adolescents were available. Of the 95 adolescents with available medical records 60 had consulted their GP for knee pain. The median number of contacts was 1.5 (range 1-7). The GPs initiated treatment for 48 of the 60 adolescents and in most cases it was information and advice (36/48) or pain medication to a minor extent (6/48). Out of the 60 adolescents who consulted their GP 26 were subsequently referred to different types of health care professionals, in 11 out of 26 to physiotherapy, but also to the department of rheumatology or orthopaedics. Conclusions : 63% of adolescents diagnosed with PFP had previously consulted their GP due to knee pain. Several types of treatments were initiated by the GP, but most commonly advice and information were given. Standardized and evidence-based treatment guidelines for adolescent knee pain in general practice are needed.

Trunk, Hip and Knee Exercise Programs for Pain Relief, Functional Performance and Muscle Strength in Patellofemoral Pain: Systematic Review and Meta-Analysis

Objective

Previous research suggests that muscle strength exercise is the most effective rehabilitation methods in patients with patellofemoral pain (PFP). This systematic review with meta-analysis compared the effects of Hip&Knee, Hip-only and Knee-only exercise programs on pain relief, muscle strength, and functional performance in patients with PFP.

Methods

Literature searches of PubMed, PEDro and CINAHL databases revealed twenty-one studies included in the final descriptive review, thirteen of which were included in the meta-analysis. Data extraction included baseline and post-intervention means and standard deviations of all eligible outcome measures both for the intervention and control groups, participants baseline demographics and intervention characteristics.

Results

The results showed that Hip&Knee and Hip-only exercise programs were comparatively effective, while the Knee-only exercise programs proved to be inferior to the above-mentioned approaches. The Hip&Knee exercise programs showed the greatest pain relief (mean difference = -1.71 (-3.11, -0.30); p = 0.02; I² = 96%) and functional improvement (standardized mean difference = 1.28 (0.45, 2.12); p = 0.003; I² = 84%), although the subgroup analysis did not show any significant difference compared to Hip-only exercise programs (p > 0.05).

Conclusion

Overall, Hip&Knee exercise programs appear to reduce pain and improve function more than other exercise programs and could be used as a primary rehabilitation approach in patients with PFP. However, the difference between the subgroups in most outcome measures suggests that Hip&Knee exercise programs are no more effective than Hip-only exercise programs.

Patient-Reported Outcome Measures in Sports Medicine: A Concise Resource for Clinicians and Researchers

BACKGROUND

Despite the importance of assessing patient outcomes during patient care, current evidence suggests relatively limited use of patient-reported outcome measures (PROMs) by athletic trainers (ATs). Major barriers to PROM use include lack of knowledge, navigating the intricate process of assessing a wide variety of PROMs, and selecting the most appropriate PROM to use for care. A concise resource for ATs to consult when selecting and implementing PROMs may help facilitate the use of PROMs in athletic health care.

OBJECTIVE

To review the instrument essentials and clinical utility of PROMs used by ATs.

METHODS

We studied 11 lower extremity region-specific, 10 upper extremity region-specific, 6 generic, and 3 single-item PROMs based on the endorsement of at least 10% of ATs who use PROMs, as reported in a recent investigation of PROM use in athletic training. A literature search was conducted for each included PROM that focused on identifying and extracting components of the instrument essentials (ie, instrument development, reliability, validity, responsiveness and interpretability, and precision) and clinical utility (ie, acceptability, feasibility, and appropriateness). Through independent review and group consensus, we also classified each PROM question by International Classification of Functioning, Disability and Health domain and health-related quality-of-life dimensions.

KEY FINDINGS

The PROMs contained in this report generally possessed appropriate instrument essentials and clinical utility. Moreover, the PROMs generally emphasized body structure and function as well as the physical functioning of the patient. Athletic trainers aiming to assess patients via a whole-person approach may benefit from combining different PROMs for use in patient care to ensure broader attention to disablement health domains and health-related quality-of-life dimensions.

Associations between number of pain sites and sleep, sports participation, and quality of life: a cross-sectional survey of 1021 youth from the Midwestern United States

BACKGROUND

Musculoskeletal pain in youth is common but little is known about the influence of the number of pain sites on pain characteristics. The objective of this study was to compare pain characteristics, quality of life, sleep, sport participation between adolescents without pain, those with single site pain, and those with multi-site pain and investigate the relationship between pain duration and number of pain sites.

METHODS

An online survey was sent via email to 7177 possible middle- and high-school students. The students completed a survey containing questions about their pain (including location, duration, intensity, frequency), health-related quality of life, sleep quantity and quality, and sports participation. Quantitative variables were analysed with one-way ANOVAs or t-tests and qualitative variables were analysed with Pearson Chi-squared tests. Relationships were investigated with a Pearson Correlation.

RESULTS

Of the respondents (n = 1021), 52.9% reported no pain, 17.2% reported pain in a single-site, and 29.9% reported pain in multiple sites. Those with multi-site pain reported significantly lower quality of life than both pain-free youth (p < 0.001) and those with single-site pain (p < 0.001); those with single-site pain had lower quality of life than pain-free youth (p < 0.001). Those with pain reported worse sleep than those without pain (P < 0.05). No differences in sport participation were found (p > 0.10). Those with multi-site pain reported greater intensity (p = 0.005) and duration (p < 0.001) than those with single-site pain. A positive, moderate, and significant correlation (r = 0.437, p < 0.001) was found between the pain duration and number of pain sites.

CONCLUSIONS

A large percentage of youth experience regular pain that affects their self-reported quality of life and sleep, with greater effects in those with multi-site pain.

Investigating the prevalence of anxiety and depression in people living with patellofemoral pain in the UK: the Dep-Pf Study

Background and aims Patellofemoral pain (PFP) is a common knee condition causing pain around or behind the kneecap which is exacerbated by certain activities. Traditionally it has been viewed as a self-limiting condition. Recent research proves this is not the case and the evidence for poor long-term outcomes is growing. Whilst the evidence base for PFP treatment and the understanding of its aetiology is improving, it remains a complex and difficult to treat condition. In many physical conditions, it has been shown that anxiety and depression negatively affect both their management and duration. It is unclear how prevalent anxiety and depression are in PFP. This study aimed to identify the prevalence of anxiety and depression in people living with PFP in the UK. Methods In order to investigate this, a cross-sectional online survey was undertaken. Four hundred participants with self-reported symptoms of PFP were recruited through a tailored social media campaign, using modified snowball sampling. Eligibility criteria were (i) aged between 18 and 44, (ii) self-reported symptoms of PFP (using accepted criteria) (iii) resident in the UK. Exclusion criteria were previous history of patella dislocation or previous surgery to affected knee. The survey recorded demographic information, previous treatment for both PFP and anxiety and depression, the Hospital Anxiety and Depression Scale and the Anterior Knee Pain Scale. Ethical approval was gained from a University of Plymouth Ethics Committee. Results Half (49.5%; n=198) of respondents were classified as experiencing anxiety and 20.8% (n=83) as experiencing depression. The levels of anxiety and depression identified in this study are higher than those found in the general population (5.9-7.8% and 3.3-7.8%, respectively). This mirrors results which have been reported in other studies into PFP in different settings and with other musculoskeletal conditions, such as osteoarthritis and contracted shoulder. Conclusions Anxiety and depression are more common in people living with PFP than in the general population. These findings support the need for greater research into the effects of psychological factors, such as anxiety and depression, in PFP. A key area of future research will be to determine whether these psychological factors affect treatment outcomes in people living with PFP. Implications This is the first study to investigate the prevalence of anxiety and depression in people living with patellofemoral pain in the UK. This study shows that anxiety and depression are very common in people living with patellofemoral pain. The need for further work into the effects of psychological factors in patellofemoral pain is indicated.

A loaded self-managed exercise programme for patellofemoral pain: a mixed methods feasibility study

BACKGROUND

A novel loaded self-managed exercise programme that includes pain education and self-management strategies may result in better outcomes for people with patellofemoral pain (PFP). However, establishing program feasibility is an essential first step before testing efficacy. The purpose of this study was to evaluate the feasibility and acceptability of conducting a definitive RCT which will evaluate the clinical and cost-effectiveness of a loaded self-managed exercise programme for people with PFP compared with usual physiotherapy.

METHODS

In a mixed methods, pragmatic, randomised controlled feasibility study, 60 participants with PFP (57% female; mean age 29 years) were recruited from a physiotherapy clinic within a large UK teaching hospital. They were randomly allocated to receive either a loaded self-managed exercise programme (n = 30) or usual physiotherapy (n = 30). Feasibility indicators of process, resources, and management were collected through follow-up of standardised questionnaires six months after recruitment and semi-structured interviews with 20 participants and physiotherapists.

RESULTS

Recruitment rate was 5 participants per month; consent rate was 99%; adherence to intervention appointments was 87%; completeness of questionnaire data was 100%; and adherence to intervention delivery was 95%. Three exercise diaries were returned at six months (5%). At six months, 25 questionnaire booklets were returned (9 in the loaded self-managed group, 16 in the usual physiotherapy group), with a total retention rate of 42%. At six months, 56% (5/9) of respondents in the loaded self-managed group and 56% (9/16) in the usual physiotherapy group were classified as 'recovered'. Both groups demonstrated improvements in average pain (VAS), kinesiophobia, pain catastrophizing, general self-efficacy and EQ-5D-5 L from baseline to six months.

CONCLUSION

The results of this feasibility study confirm that it is feasible and acceptable to deliver a loaded self-managed exercise programme to adults with PFP in an NHS physiotherapy outpatient setting. However, between group differences in lost to follow up and poor exercise diary completion mean we are uncertain on some feasibility aspects. These methodological issues need addressing prior to conducting a definitive RCT.

TRIAL REGISTRATION

ISRCTN 35272486 . Registered 19th December 2016.

Prevalence of patellofemoral pain and knee pain in the general population of Chinese young adults: a community-based questionnaire survey

Background

Previous studies that have described the prevalence of patellofemoral pain (PFP) have been limited to samples of military personnel or sporting populations, and convincing data in the general Chinese population are lacking. The present study defined the prevalence of PFP and knee pain in the general population of Chinese young adults and evaluated whether gender, age, or body mass index (BMI) were associated with PFP.

Methods

An anonymous online questionnaire survey was open to the general public in China. A self-report questionnaire was used to specifically identify PFP. The population aged 18–40 years was enrolled in the study and completed the questionnaire. The prevalence of PFP and knee pain in the overall sample and in subgroups stratified by sex, age, and BMI was estimated. Logistic regression analysis was conducted to determine if there was a significant association between PFP and sex, age, or BMI.

Results

A total of 1153 participants were enrolled in the study. The prevalence of PFP in the overall sample and among the male and female participants was 20.7, 20.3, and 21.2%, respectively. The prevalence of the knee pain in the overall sample and among the male and female participants was 35.6, 38.2, and 33.7%, respectively. The prevalence of PFP in the subgroups stratified by age and BMI did not differ significantly between the groups. Gender, age, and BMI did not have significant associations with the prevalence of PFP.

Conclusion

PFP is common in the general Chinese population. Clinicians should direct more attention toward the early diagnosis of and interventions for PFP.

Exercise therapy, patient education, and patellar taping in the treatment of adolescents with patellofemoral pain: a prospective pilot study with 6 months follow-up

Background

Patellofemoral pain (PFP) is the most common knee condition among adolescents, with a prevalence of 6–7% resulting in reduced function and quality of life. Exercise therapy is recommended for treating PFP, but has only been tested in older adolescents (15–19 years). This pilot study aimed to investigate the adherence to, and clinical effects of, exercise and patient education in young adolescents (12–16 years), with PFP.

Methods

Twenty adolescents (16 females) with PFP were recruited from a population-based cohort to undergo a 3-month multimodal intervention. This comprised of a 30-min patient education and group-based exercise therapy. Exercises included supervised lower extremity strength exercises three times per week, in addition to similar home-based strength exercises. Outcomes included a 7-point global rating of change scale (ranging from “completely recovered” to “worse than ever”), the Knee injury and Osteoarthritis Outcome Score (KOOS), physical activity scale (PAS), weekly sports participation and health-related quality of life measured by European Quality of Life 5 dimensions Youth (EQ-5DY) and isometric knee and hip muscle strength. Pain was measured on a visual analogue scale (VAS), and satisfaction treatment was measured on a five-point Likert scale ranging from “highly satisfied” to “not satisfied at all”. These were collected at 3- and 6-month follow-ups. Adherence to supervised exercise was measured as session attendance, and adolescent self-reported adherence to home-based exercises.

Results

Adherence to the exercise therapy was poor, with adolescents participating in a median of 16 (IQR 5.5–25) out of 39 possible supervised training session. Five out of 18 adolescents had a successful outcome after both 3 and 6 months. There were no relevant changes in isometric muscle strength.

Conclusion

This was the first study to investigate adherence to, and clinical effects of, exercise therapy and patient education in young adolescents with patellofemoral pain. Adherence to the exercise therapy was low with little to no clinical effects making a full clinical trial impractical. Future studies need to explore how an intervention can be successfully tailored to young adolescents with patellofemoral pain to obtain good adherence while improving pain and function.

Neuromuscular electrical stimulation (NMES) for patellofemoral pain syndrome

BACKGROUND

Patellofemoral pain syndrome, now generally referred to as patellofemoral pain (PFP), is one of the most common orthopaedic disorders, characterised by pain in the anterior or retropatellar knee region. Neuromuscular electrical stimulation (NMES) has been proposed generally as a complementary treatment, associated with other interventions such as exercise, or as a single treatment to increase muscle force, reduce knee pain, and improve function.

OBJECTIVES

To assess the effects (benefits and harms) of neuromuscular electrical stimulation for people with patellofemoral pain.

SEARCH METHODS

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, PEDro, CINAHL, SPORTDiscus, AMED, LILACS, trial registers, conference abstracts, and reference lists. We carried out the search in May 2017.

SELECTION CRITERIA

We included randomised controlled clinical trials that evaluated the use of NMES for people with PFP.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed the process of study selection, data extraction, and 'Risk of bias' assessment in duplicate. The primary outcomes were knee pain, knee function, and adverse events. The timing of outcome measurements was up to three months (short term), three to 12 months (medium term), and 12 months and above from trial entry (long term). We calculated risk ratios for dichotomous data and mean differences or standardised mean differences for continuous data. Where appropriate, we pooled data using the fixed-effect model.

MAIN RESULTS

We included eight randomised clinical trials, reporting results for 345 participants with PFP. The mean ages of trial populations ranged from 25 to 43 years, and the majority (53% to 100%) of participants were female. There was a wide duration of symptoms, with the minimum duration of symptoms for trial inclusion ranging from one to six months. In addition to the study inclusion criteria, studies varied widely in the characteristics of the NMES and its application, and associated co-interventions. We assessed all trials as at high risk of bias in at least one domain, particularly blinding and incomplete outcome data. The results of a laboratory-based trial reporting knee pain immediately after a single 15-minute session of NMES are not reported here as these are of questionable clinical relevance. The seven remaining trials provided evidence for three comparisons. We assessed the overall quality of the evidence, using GRADE, for all primary outcomes for all comparisons as very low, thus we are very unsure of the findings.Four studies compared NMES plus exercise versus exercise alone. Patellar taping was applied as well as exercise to all participants of one study, and patellar taping and ice were also applied in another study. Each trial tested a different multiple-session NMES programme. Pooled data from three studies (118 participants) provided very low-quality evidence that NMES is associated with reduced pain at the end of treatment (ranging from 3 to 12 weeks): mean difference -1.63, 95% confidence interval (CI) -2.23 to -1.02; visual analogue scale (VAS) 0 to 10; higher scores = worse pain. However, this result may not be clinically relevant since the minimal clinically important difference for VAS during activities (1.5 to 2.0, out of 10 points) lies within the 95% CI. We found very low-quality evidence from pooled data from two trials of little effect of NMES on knee function, as measured by two knee function rating systems. We found inconclusive and very low-quality evidence from one trial (29 participants) of little effect of NMES on pain and function at one-year follow-up. None of the four trials reported on adverse effects of treatment.One study (94 participants) compared NMES, applied four hours per day on a daily basis for four weeks, with two types of exercises (isometric and isokinetic). The study did not report on knee pain or adverse events. The study provided very low-quality evidence of no important difference between the two groups in knee function at the end of the four-week treatment. Of note is the potentially onerous NMES schedule in this study, which does not correspond to that typically used in clinical practice.Two studies compared different types of NMES. Simultaneously delivered high-low frequencies NMES was compared with sequentially delivered high-low frequencies NMES in one trial (14 participants) and with fixed frequency NMES in the second trial (64 participants). The studies provided very low-quality evidence of no important differences at the end of the six-week treatment programme between the simultaneous frequencies NMES and the two other NMES programmes in overall knee pain, knee function, or in quadriceps fatigue (an adverse event).

AUTHORS' CONCLUSIONS

This review found insufficient and inconclusive evidence from randomised controlled trials to inform on the role of NMES for treating people with PFP in current clinical practice. The very low-quality evidence available means that we are uncertain whether or not a multiple-session programme of NMES combined with exercise over several weeks versus exercise alone results in clinically important differences in knee pain and function at the end of the treatment period or at one year. There were no data on adverse effects such as muscle fatigue and discomfort. High-quality randomised clinical trials are needed to inform on the use of NMES for people with PFP. However, professional and stakeholder consensus is required on prioritisation of the research questions for interventions for treating people with PFP, including on the NMES treatment protocol for trials testing NMES.

Study protocol: a mixed methods feasibility study for a loaded self-managed exercise programme for patellofemoral pain

Background

Patellofemoral pain (PFP) is one of the most common forms of knee pain in adults under the age of 40, with a prevalence of 23% in the general population. The long-term prognosis is poor, with only one third of people pain-free 1 year after diagnosis.

The biomedical model of pain in relation to persistent PFP has recently been called into question. It has been suggested that interventions for chronic musculoskeletal conditions should consider alternative mechanisms of action, beyond muscles and joints. Modern treatment therapies should consider desensitising strategies, with exercises that target movements and activities patients find fearful and painful.

High-quality research on exercise prescription in relation to pain mechanisms, not directed at specific tissue pathology, and dose response clearly warrants further investigation.

Our primary aim is to establish the feasibility and acceptability of conducting a definitive RCT which will evaluate the clinical and cost-effectiveness of a loaded self-managed exercise programme for people with patellofemoral pain.

Method

This is a single-centred, multiphase, sequential, mixed-methods trial that will evaluate the feasibility of running a definitive large-scale randomised controlled trial of a loaded self-managed exercise programme versus usual physiotherapy. Initially, 8–10 participants with a minimum 3-month history of PFP will be recruited from an NHS physiotherapy waiting list and interviewed. Participants will be invited to discuss perceived barriers and facilitators to exercise engagement, and the meaning and impact of PFP. Then, 60 participants will be recruited in the same manner for the main phase of the feasibility trial. A web-based service will randomise patients to a loaded self-managed exercise programme or usual physiotherapy. The loaded self-managed exercise programme is aimed at addressing lower limb knee and hip weakness and is positioned within a framework of reducing fear/avoidance with an emphasis on self-management. Baseline assessment will include demographic data, average pain within the last week (VAS), fear avoidance behaviours, catastrophising, self-efficacy, sport and leisure activity participation, and general quality of life. Follow-up will be 3 and 6 months. The analysis will focus on descriptive statistics and confidence intervals. The qualitative components will follow a thematic analysis approach.

Discussion

This study will evaluate the feasibility of running a definitive large-scale trial on patients with patellofemoral pain, within the NHS in the UK. We will identify strengths and weaknesses of the proposed protocol and the utility and characteristics of the outcome measures. The results from this study will inform the design of a multicentre trial.

Trial registration

ISRCTN35272486.

Knee pain in adolescents: prevalence, risk factors, and functional impairment

•

Knee pain prevalence over the last 7 days was 22.6%.

•

Knee functionality was investigated using the Knee injury and Osteoarthritis Outcome Score.

•

More knee pain was found in older adolescents who do not have physical education at school.

•

Functional impairment in girls and adolescents who are physically active in their leisure time.

Objective

To investigate knee pain prevalence, associated factors, and functional impairment among adolescents.

Method

This was a cross-sectional study conducted between May and June 2014 with a random sample of 619 adolescents aged between 10 and 17 years. Knee pain prevalence was investigated using the Nordic Questionnaire for Osteomuscular Symptoms and a number of independent variables (demographic data, nutritional status, form of carrying backpacks, and pain during and after walking) obtained by self-report questionnaires. Physical impairment of the knee was assessed using the Brazilian version of the Knee injury and Osteoarthritis Outcome Score questionnaire. Poisson regression analysis was used to estimate the ratios of crude and adjusted knee pain association with the investigated factors. ANOVA and Kruskal–Wallis tests were used to compare median functional impairment.

Results

Knee pain prevalence over the last 7 days was 22.6%. Factors having significant association with the outcome were: being between 12 and 14 years old (PR: 1.67; 95% CI: 1.07–2.58; p < 0.01), being between 15 and 17 years old (PR: 2.44; 95% CI: 1.51–3.94; p = 0.01), and not doing physical education at school (PR: 0.54; 95% CI: 0.35–0.82; p = 0.01). Total functional capacity among adolescents with pain was significantly lower among girls (68.7 points; PD ± 15.1) when compared with boys (74.3 points; PD ± 12.7) (p = 0.02). The mean value of disabling pain was lower (55.1 points; PD ± 12.3) among adolescents who were physically active in their leisure time compared to those who were insufficiently active (60.4 points; PD ± 12.4) (p = 0.02).

Conclusion

The results of this study show that knee pain among adolescents with no previous history should be investigated, particularly among older adolescents who do not have physical education at school, since it is highly prevalent and can result in functional impairment. Regarding functionality, more attention should be given to girls and adolescents who were physically active in their leisure time.

Effectiveness of Manual Therapy Combined With Physical Therapy in Treatment of Patellofemoral Pain Syndrome: Systematic Review

OBJECTIVES

The purpose of this study was to conduct a review of randomized controlled trials (RCTs) to determine the treatment effectiveness of the combination of manual therapy (MT) with other physical therapy techniques.

METHODS

Systematic searches of scientific literature were undertaken on PubMed and the Cochrane Library (2004-2014). The following terms were used: "patellofemoral pain syndrome," "physical therapy," "manual therapy," and "manipulation." RCTs that studied adults diagnosed with patellofemoral pain syndrome (PFPS) treated by MT and physical therapy approaches were included. The quality of the studies was assessed by the Jadad Scale.

RESULTS

Five RCTs with an acceptable methodological quality (Jadad ≥ 3) were selected. The studies indicated that MT combined with physical therapy has some effect on reducing pain and improving function in PFPS, especially when applied on the full kinetic chain and when strengthening hip and knee muscles.

CONCLUSIONS

The different combinations of MT and physical therapy programs analyzed in this review suggest that giving more emphasis to proximal stabilization and full kinetic chain treatments in PFPS will help better alleviation of symptoms.

A questionnaire to identify patellofemoral pain in the community: an exploration of measurement properties

BACKGROUND

Community-based studies of patellofemoral pain (PFP) need a questionnaire tool that discriminates between those with and those without the condition. To overcome these issues, we have designed a self-report questionnaire which aims to identify people with PFP in the community.

METHODS

STUDY DESIGNS

comparative study and cross-sectional study.

STUDY POPULATION

comparative study: PFP patients, soft-tissue injury patients and adults without knee problems. Cross-sectional study: adults attending a science festival.

INTERVENTION

comparative study participants completed the questionnaire at baseline and two weeks later. Cross-sectional study participants completed the questionnaire once. The optimal scoring system and threshold was explored using receiver operating characteristic curves, test-retest reliability using Cohen's kappa and measurement error using Bland-Altman plots and standard error of measurement. Known-group validity was explored by comparing PFP prevalence between genders and age groups.

RESULTS

Eighty-four participants were recruited to the comparative study. The receiver operating characteristic curves suggested limiting the questionnaire to the clinical features and knee pain map sections (AUC 0.97 95 % CI 0.94 to 1.00). This combination had high sensitivity and specificity (over 90 %). Measurement error was less than the mean difference between the groups. Test-retest reliability estimates suggest good agreement (N = 51, k = 0.74, 95 % CI 0.52-0.91). The cross-sectional study (N = 110) showed expected differences between genders and age groups but these were not statistically significant.

CONCLUSION

A shortened version of the questionnaire, based on clinical features and a knee pain map, has good measurement properties. Further work is needed to validate the questionnaire in community samples.

Effect of exercise therapy on neuromuscular activity and knee strength in female adolescents with patellofemoral pain-An ancillary analysis of a cluster randomized trial

BACKGROUND

Female adolescents with patellofemoral pain are characterized by altered neuromuscular knee control and reduced maximal quadriceps torque. The purpose of this study is to investigate whether exercise therapy and patient education are associated with larger improvements in neuromuscular knee control and maximal quadriceps torque compared with patient education alone.

METHODS

This is an ancillary analysis of a cluster randomized controlled trial investigating the effect of patient education and exercise therapy on self-reported recovery in 121 adolescents with patellofemoral pain. A random subsample of 57 female adolescents was included and tested at baseline and after 3months. Neuromuscular control of the knee was quantified as the complexity of surface electromyography of the vastus lateralis and vastus medialis during stair descent. Secondary outcomes were complexity of knee flexion/extension kinematics and maximal quadriceps torque.

FINDINGS

There was an 8-15% greater decrease in the complexity of surface electromyography suggesting an improvement in neuromuscular knee control among those randomized to exercise therapy (0.08<p<0.30). Adolescents randomized to exercise therapy had a 0.28-Nm/kg (95% CI: 0.05-0.52; p=0.02) larger increase in maximal quadriceps torque.

INTERPRETATION

Female adolescents randomized to patient education and exercise therapy had a significantly larger increase in maximal quadriceps torque and greater improvement in neuromuscular knee control during stair descent than those receiving patient education alone. This suggest that exercise therapy has an effect not only on self-reported outcome measures but also on objective measures of thigh muscle function in female adolescents with patellofemoral pain.

Is Knee Pain During Adolescence a Self-limiting Condition? Prognosis of Patellofemoral Pain and Other Types of Knee Pain

BACKGROUND

The prevalence of adolescent knee pain is 33%, and patellofemoral pain (PFP) is the most common diagnosis with a nontraumatic onset. The 2-year prognosis of adolescent PFP compared with other types of knee pain is unknown.

PURPOSE

To investigate the 2-year prognosis of knee pain among adolescents with and without a diagnosis of PFP.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

In 2011, a cohort of 2200 adolescents aged 15 to 19 years answered an online questionnaire on musculoskeletal pain. Of these, 504 reported knee pain, and 153 of these were clinically diagnosed with PFP. After 2 years, the 504 adolescents, as well as 252 randomly selected adolescents who did not report knee pain in 2011, were contacted again. Primary outcome at follow-up was the proportion of adolescents with knee pain during the last week prior to follow-up.

RESULTS

Overall, 55.9% (95% CI, 50.8%-60.9%) of those reporting knee pain at baseline also reported pain 2 years later. Adolescents diagnosed with PFP had a 1.26 (95% CI, 1.05-1.50) higher relative risk (RR) of knee pain at follow-up compared with other types of knee pain. Adolescents with PFP were significantly more likely to reduce or stop sports participation compared with adolescents with other types of knee pain. Of those without knee pain at baseline, 12.8% (95% CI, 8.4%-17.2%) reported knee pain at follow-up in 2013. Adolescents with knee pain at baseline had a 4.51 (95% CI, 3.15-6.45) higher RR of knee pain at follow-up compared with adolescents without knee pain at baseline.

CONCLUSION

Knee pain during adolescence, and PFP in particular, is in most cases present after 2 years and thus may not be self-limiting. A greater focus on early detection and prevention of knee pain during adolescence is needed.

A review of knee pain in adolescent females

Primary care practitioners are in a position to educate patients and parents about the risk factors that may increase the incidence of knee pain in adolescent females. This article highlights patellofemoral pain syndrome, Sinding-Larsen-Johansson syndrome, Osgood-Schlatter disease, and meniscal tears.

High prevalence of daily and multi-site pain--a cross-sectional population-based study among 3000 Danish adolescents

Background

Daily pain and multi-site pain are both associated with reduction in work ability and health-related quality of life (HRQoL) among adults. However, no population-based studies have yet investigated the prevalence of daily and multi-site pain among adolescents and how these are associated with respondent characteristics. The purpose of this study was to investigate the prevalence of self-reported daily and multi-site pain among adolescents aged 12–19 years and associations of almost daily pain and multi-site pain with respondent characteristics (sex, age, body mass index, HRQoL and sports participation).

Methods

A population-based cross-sectional study was conducted among 4,007 adolescents aged 12–19 years in Denmark. Adolescents answered an online questionnaire during physical education lessons. The questionnaire contained a mannequin divided into 12 regions on which the respondents indicated their current pain sites and pain frequency (rarely, monthly, weekly, more than once per week, almost daily pain), characteristics, sports participation and HRQoL measured by the EuroQoL 5D. Multivariate regression was used to calculate the odds ratio for the association between almost daily pain, multi-site pain and respondent characteristics.

Results

The response rate was 73.7%. A total of 2,953 adolescents (62% females) answered the questionnaire. 33.3% reported multi-site pain (pain in >1 region) while 19.8% reported almost daily pain. 61% reported current pain in at least one region with knee and back pain being the most common sites. Female sex (OR: 1.35-1.44) and a high level of sports participation (OR: 1.51-2.09) were associated with increased odds of having almost daily pain and multi-site pain. Better EQ-5D score was associated with decreased odds of having almost daily pain or multi-site pain (OR: 0.92-0.94).

Conclusion

In this population-based cohort of school-attending Danish adolescents, nearly two out of three reported current pain and, on average, one out of three reported pain in more than one body region. Female sex, and high level of sports participation were associated with increased odds of having almost daily pain and multi-site pain. The study highlights an important health issue that calls for investigations to improve our understanding of adolescent pain and our capacity to prevent and treat this condition.

Hip and knee strength is not affected in 12-16 year old adolescents with patellofemoral pain--a cross-sectional population-based study

Background

One of the rationales behind using strength training in the treatment of adolescents with Patellofemoral Pain (PFP) is that reduced strength of the lower extremity is a risk factor for PFP and a common deficit. This rationale is based on research conducted on adolescents >15 years of age but has never been investigated among young adolescents with PFP.

Objectives

To compare isometric muscle strength of the lower extremity among adolescents with PFP compared to age- and gender-matched pain-free adolescents.

Methods

In 2011 a population-based cohort (APA2011-cohort) consisting of 768 adolescents aged 12–15 years from 8 local schools was formed. In September 2012, all adolescents who reported knee pain in September 2011 were offered a clinical examination if they still had knee pain. From these, 20 adolescents (16 females) were diagnosed with PFP. Pain-free adolescents from the APA2011-cohort (n = 20) were recruited on random basis as age- and gender-matched pairs. Primary outcome was isometric knee extension strength normalized to body weight (%BW) and blinded towards subject information. Secondary outcomes included knee flexion, hip abduction/adduction and hip internal/external rotation strength. Demographic data included Knee Injury and Osteoarthritis Outcome Score (KOOS) and symptom duration.

Results

Adolescents with PFP reported long symptom duration and significantly worse KOOS scores compared to pain-free adolescents. There were no significant differences in isometric knee extension strength (Δ0.3% BW, p = 0.97), isometric knee flexion strength (Δ0.4% BW, p = 0.84) or different measures of hip strength (Δ0.4 to 1.1% BW, p>0.35).

Conclusion

Young symptomatic adolescents with PFP between 12 and 16 years of age did not have decreased isometric muscle strength of the knee and hip. These results question the rationale of targeting strength deficits in the treatment of adolescents with PFP. However, strength training may still be an effective treatment for those individuals with PFP suffering from strength deficits.

Care-seeking behaviour of adolescents with knee pain: a population-based study among 504 adolescents

BACKGROUND

Knee pain is common during adolescence. Adolescents and their parents may think that knee pain is benign and self-limiting and therefore avoid seeking medical care. However, long-term prognosis of knee pain is not favourable and treatment seems to offer greater reductions in pain compared to a "wait-and-see" approach. The purpose of this study was to describe the determinants of care-seeking behaviour among adolescents with current knee pain and investigate what types of treatment are initiated.

METHODS

An online questionnaire was forwarded to 2,846 adolescents aged 15-19 in four upper secondary schools. The questionnaire contained questions on age, gender, height, weight, currently painful body regions, frequency of knee pain, health-related quality of life measured by the EuroQol 5-dimensions, sports participation and if they had sought medical care. Adolescents who reported current knee pain at least monthly or more frequently were telephoned. The adolescents were asked about pain duration, onset of knee pain (traumatic or insidious) and if they were currently being treated for their knee pain.

RESULTS

504 adolescents currently reported at least monthly knee pain. 59% of these had sought medical care and 18% were currently under medical treatment . A longer pain duration and higher pain severity increased the odds of seeking medical care. Females with traumatic onset of knee pain were more likely to have sought medical care than females with insidious onset of knee pain. Females with traumatic onset of knee pain and increased pain severity were more likely to be undergoing medical treatment. The most frequently reported treatments were the combination of exercises and orthotics (68% of those undergoing medical treatment).

CONCLUSION

Females with insidious onset of knee pain do not seek medical care as often as those with traumatic onset and adolescents of both genders with insidious onset are less likely to be under medical treatment. These findings are important as knee pain with insidious onset has similar consequences as knee pain with traumatic onset regarding pain severity, pain duration and reductions in health-related quality of life.

Lower mechanical pressure pain thresholds in female adolescents with patellofemoral pain syndrome

STUDY DESIGN

Cross-sectional study.

OBJECTIVES

To compare pressure pain thresholds (PPTs) between adolescent females diagnosed with patellofemoral pain syndrome (PFPS) and gender- and age-matched controls without musculoskeletal pain.

BACKGROUND

PFPS is prevalent among adolescents and may be associated with reduced PPT both locally and remotely from the site of reported pain. This may indicate altered central processing of nociceptive information. However, this has never been investigated in adolescents with PFPS.

METHODS

Adolescents with PFPS and a comparison group without musculoskeletal pain were recruited from a population-based cohort of students from 4 upper secondary schools, aged 15 to 19 years. All 2846 students within that age range were invited to answer an online questionnaire regarding musculoskeletal pain. The students who reported knee pain were contacted by telephone and offered a clinical examination by an experienced rheumatologist, who made a diagnosis. PPTs were measured at 4 sites around the knee and 1 site on the tibialis anterior in the 57 female adolescents diagnosed with PFPS and in 22 female adolescents without musculoskeletal pain.

RESULTS

Adolescents with PFPS, compared to controls, had significantly lower PPTs (26%-37% [100-178 kPa]) at each of the 4 sites around the knee, suggesting localized hyperalgesia. On the tibialis anterior, adolescents with PFPS had a 33% (159 kPa) lower PPT (distal hyperalgesia) compared with controls.

CONCLUSION

These findings suggest that adolescent females with PFPS have localized and distal hyperalgesia. These findings may have implications for treating PFPS, as both peripheral and central mechanisms may be driving the pain. Registered at clinicaltrials.gov (NCT01438762).

The effect of McConnell taping on vastus medialis and lateralis activity during squatting in adults with patellofemoral pain syndrome

This study aims to examine the effect of McConnell taping to patients with patellofemoral pain syndrome on the change of the muscle activity of vastus medialis and vastus lateralis during squatting. The total numbers of participants are 16 patients with pain in their knee. There are three different experiments: no-taping, placebo taping, and McConnell taping. As a result, both the muscle activity of vastus medialis and muscle activity ratio of vastus medialis to vastus lateralis increased in placebo taping compared to no-taping, which wasn't statistically significant. However, the muscle activity of vastus medialis and muscle activity ratio of vastus medialis to vastus lateralis increased in McConnell taping compared to no-taping, which was statistically significant. These results suggest that McConnell taping affects the activity of quadriceps by changing the position of the patella, and thus can effectively be applied in the treatment of patellofemoral pain syndrome.