Effectiveness of core muscle strengthening for improving pain and dynamic balance among female patients with patellofemoral pain syndrome

Clinic- and laboratory-based measures of postural control in patellofemoral pain: A systematic review with meta-analysis and evidence gap map

BACKGROUND

Patellofemoral pain (PFP) is a prevalent musculoskeletal disorder associated with functional impairments. Although postural control is commonly assessed in people with PFP, there are inconsistent results regarding potential postural control deficits in this population.

RESEARCH QUESTION

This review aims to evaluate whether postural control is impaired in people with patellofemoral pain (PFP) and the effectiveness of interventions on postural control measures.

METHODS

We searched six databases from their inception to May 5, 2023. We included studies assessing clinic- or laboratory-based postural control measures in people with PFP compared to pain-free controls, and intervention studies with PFP populations. We assessed risk of bias using the Joanna Briggs Institute critical appraisal checklists and the Cochrane Risk of Bias 2 tool. We assessed the certainty of evidence using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. We used random-effects meta-analyses considering subgroups based on type of task, measure, and intervention.

RESULTS

Fifty-three studies were included. Very low certainty evidence indicated that people with PFP have shorter anterior (SMD = 0.53, 95 %CI:0.16,0.90), posteromedial (SMD = 0.54, 95 %CI:0.04,1.03) and posterolateral (SMD = 0.59, 95 %CI:0.11,1.07) reach distance, and worse composite score (SMD = 0.46, 95 %CI:0.22,0.70). Very low to moderate certainty evidence indicated that people with PFP have worse anterior-posterior and overall stability indexes during single-leg stance (SMD = -0.71, 95 %CI:-1.29,-0.14; SMD = -0.63, 95 %CI:-0.94,-0.32) and overall stability index during double-leg stance (SMD = -0.39, 95 %CI:-0.78,-0.00), but no differences in center of pressure area during stair ascent (SMD = 0.32, 95 %CI:-2.72, 3.36). Low certainty evidence indicated that kinesio taping improved anterior reach distance (SMD = -0.49, 95 %CI:-0.89,-0.09), while no significant differences were observed between pre- and post-intervention outcomes for conventional rehabilitation and rigid taping.

SIGNIFICANCE

Clinicians should use clinic- (star excursion or Y-balance tests) and laboratory-based (stability indexes) measures to identify impairments of postural control in people with PFP. Low certainty of evidence suggests short-term improvement in postural control with kinesio taping.

Motion Analysis of Core Stabilization Exercise in Women: Kinematics and Electromyographic Analysis

As core stabilization exercise is essential for maintaining a stable spine and improving functional performance, understanding the activation of core muscles and the stabilization of the trunk and pelvis during such exercise is crucial. The purpose of this study was to investigate the muscle activation and stabilization of the lumbar–pelvic region during core stabilization exercise, with a specific focus on analyzing EMG and 3D motion kinematic data. The study aimed to understand how different tension settings on the reformer affect muscle activation and hip motion, as well as how these factors impact pelvic and trunk stability during the exercise. The reformer consists of a carriage that slides back and forth on rails, with springs providing resistance. The springs can be adjusted to vary the resistance level. Twenty-eight healthy women participating in this study were asked to perform ‘side splits’, a hip abduction exercise, on the reformer in both heavy and light tension settings. Activation of the internal oblique (IO), rectus abdominis (RA), multifidus (MU), costal lumbosacral (IL), gluteus medius (GM), and adductor muscles (AL) were measured using electromyography (EMG) and 3D motion. Kinematic data using an assay were also measured during exercise. GM, IO, and MU muscles were more active when heavy springs were used, and AL muscles were more active when light springs were used. Hip motion was more symmetrical when lighter springs were used with a greater range of hip motion. There was less pelvis and torso weight transfer and more torso and pelvis stability when the heavier springs were used. In this study, we confirmed that core stabilization exercise on an unstable surface activates the deep muscles of the abdomen and back and is effective for pelvic and trunk stabilization training.

Rehabilitation of anterior knee pain in the pregnant athlete: Considerations and modifications by trimester

BACKGROUND

Anterior knee pain is a common symptom many females experience during pregnancy. There are several musculoskeletal changes that occur in anatomy and physiology throughout the course of pregnancy that impact the lower extremity kinetic chain. Pregnant athletes, recreational through competitive, who attempt to maintain a high activity level through each trimester may be at increased risk for anterior knee pain due to a greater demand for lumbopelvic and hip stabilization.

CLINICAL QUESTION

What are the evidence-driven rehabilitation guidelines and specific modifications needed to treat anterior knee pain in the female athlete during each trimester of pregnancy?

KEY RESULTS

We aim to provide an overview of rehabilitation treatment guidelines for pregnant females with anterior knee pain, presenting specific physiological changes and rationale for modifications, discussed by trimester. We recommend our program be conducted under the supervision of a physical therapist working closely with the athlete's obstetrics and sports medicine team.

CLINICAL APPLICATION

The number of women who are active during pregnancy is increasing. We provide an overview of the guidelines and considerations for treating women with anterior knee pain during a healthy and uneventful pregnancy.

Adding neuromuscular training to a strengthening program did not produce additional improvement in clinical or kinematic outcomes in women with patellofemoral pain: A blinded randomised controlled trial

BACKGROUND

Patellofemoral pain (PFP) is a knee pain condition with multifactorial aetiology, twice common in women. The recommended conservative treatment is based on strengthening of the core, hip, and knee musculatures. Addition of neuromuscular training to a strengthening protocol might provide further benefits on pain, function, and kinematics in PFP individuals. However, evidence for the effectiveness of this protocol is lacking.

OBJECTIVE

To investigate whether adding neuromuscular training to strengthening program could provide any additional improvements of pain, function, and kinematics in PFP women.

METHODS

71 PFP women were randomly into two groups and submitted to different interventions for 12 weeks. The strengthening group (SG) performed strengthening exercises for the trunk, hip, and knee muscles, while the neuromuscular training group (NMTG) performed the same exercises as SG, plus neuromuscular training from the 4th week onwards. The primary outcomes were pain intensity, function, and 2-D kinematics of the trunk and lower limb. The secondary outcomes were isometric muscle strength and patient satisfaction level. All outcomes were evaluated at 12 weeks, immediately post-treatment.

RESULTS

At 12 weeks, there was no evidence of between-group differences for any outcome, but both interventions provided clinically significant improvements for pain intensity (SG: mean difference -3.9, 95% confidence interval [CI] -5.0, -2.9; NMTG: mean difference -3.1, 95% CI -4.1, -2.0) and function (SG: mean difference 15.3, 95% CI 11.5, 19.2; NMTG: mean difference 16.9, 95% CI 13.2, 20.7).

CONCLUSION

Neuromuscular training did not produce any additional benefits for pain, function, or kinematics at 12 weeks of treatment.

Is Postural Control Affected in People with Patellofemoral Pain and Should it be Part of Rehabilitation? A Systematic Review with Meta-analysis

BACKGROUND

Growing evidence supports that exercise therapy is effective for patellofemoral pain (PFP) rehabilitation. Nevertheless, the improvements have been reported not to be sustained in the long term, suggesting that the current protocols may not comprehend all required functional factors to provide a consistent recovery. A potential neglected factor in treatment protocols for PFP is postural control. However, it is unclear whether this population presents balance impairments or the influence of postural control on pain and function during rehabilitation programmes.

OBJECTIVE

To investigate whether (Q1) balance is impaired in people with PFP compared to controls, (Q2) conservative interventions are effective to improve balance in people with PFP, and (Q3) balance exercises are effective to improve pain and function in people with PFP.

DATA SOURCES

Medline, Embase, CINAHL, SPORTDiscus, Web of Science and Cochrane Library, supplemented by hand searching of reference lists, citations and relevant systematic reviews in the field.

METHODS

A systematic review with meta-analysis was conducted according to the Cochrane recommendations and reported according to the PRISMA statement recommendations. We included cross-sectional studies comparing balance between people with and without PFP; and randomised controlled trials verifying the effect of conservative intervention on balance and the effect of balance intervention on pain and function in people with PFP. The risk of bias was assessed using the Epidemiological Appraisal Instrument for cross-sectional studies and the Physiotherapy Evidence Database scale for randomised controlled trials.

RESULTS

From 15,436 records, 57 studies (Q1 = 28, Q2 = 23, Q3 = 14) met the eligibility criteria. Meta-analyses indicated that people with PFP have worse anteroposterior (very low grade evidence, standardised mean difference [SMD] = 1.03, 95% CI 0.40-1.66) and mediolateral (moderate grade evidence, SMD = 0.87, 95% CI 0.31-1.42) balance compared to controls. Moderate grade evidence indicated that overall balance is not affected in people with PFP (SMD = 0.38, 95% CI - 0.05-0.82). Low to very low grade evidence indicates that interventions are ineffective for mediolateral (SMD = 0.01, 95% CI - 0.51-0.53) and overall (SMD = 0.49, 95% CI - 0.14-1.11) balance improvements, and low grade evidence indicates that interventions are effective to improve anteroposterior balance (SMD = 0.64, 95% CI 0.04-1.23). Moderate to low grade evidence indicated that balance interventions are effective to reduce pain (SMD = 0.82, 95% CI 0.26-1.38) and improve function (SMD = 0.44, 95% CI 0.09-0.80) when measured using questionnaires; and very low grade evidence indicated no efficacy for function measured via functional tests (SMD = 0.73, 95% CI - 0.16-1.61).

CONCLUSION

People with PFP likely present balance deficits compared to asymptomatic people. There was insufficient evidence to support the efficacy of interventions to improve or modify balance in people with PFP. Also, there was insufficient evidence to support the efficacy of balance exercises to improve pain and function in people with PFP. Trial Registration The present systematic review was registered in PROSPERO (CRD42018091717).

Effects of Patellofemoral Pain Syndrome on Changes in Dynamic Postural Stability during Landing in Adult Women

Background

This study investigated the effects of lower limb movements on dynamic postural stability (DPS) during drop landing in adult women with patellofemoral pain syndrome (PFPS).

Methods

Thirty-eight adult women were recruited and divided into two groups, the PFPS group and the control group. The study participants performed a single-leg drop landing from a 30 cm box, and their lower limb movements and DPS were measured. Differences between groups were examined using independent sample t-tests. In addition, stepwise multiple linear regression was used to examine the kinematic parameters that contribute to the DPS.

Results

The PFPS group had significantly lower hip flexion, internal rotation, knee flexion, ankle external rotation, pelvic oblique, tilt, rotation, and higher hip abduction, knee valgus, and ankle plantarflexion. In terms of DPS, the PFPS group had a significantly higher anteroposterior and a lower mediolateral than that of the control group. In the control group, regression analysis revealed a controlled anteroposterior using knee flexion, while the PFPS group controlled mediolateral through ankle plantarflexion.

Conclusions

Patients with PFPS experienced more shock on their knee joint during landing than patients in the control group with greater anteroposterior instability and lower mediolateral instability.

SEBT in individuals with patellofemoral pain: an integrative review

Abstract Introduction: Decreased postural stability can be observed in individuals with patellofemoral pain (PP). The Star Excursion Balance Test (SEBT) is widely used to assess deficits that need to be improved, with different application methods and result presentation formats. Objective: To map SEBT use in individuals with PP, characterizing the studies that applied it to identify different application methods and result presentation formats. Methods: The review included randomized and non-randomized clinical trials, cross-sectional, case-control and cohort studies. Searches were performed in Pubmed and SciElo databases. Data extracted from eligible studies were divided into categories: (I) study characterization (II) SEBT application methods and result presentation formats. Results: A total of 177 studies were identified in the databases, 13 of which were selected. There are a growing number of new studies that assess the dynamic postural control of individuals with PP using the SEBT, and a variety of test application and result presentation formats. Conclusion: The SEBT is a useful, easy-to-apply test that identifies changes in dynamic postural control in individuals with PP. Different application and result presentation formats are in accordance with the literature, but it is recommended that future studies apply the protocols most widely used in previous studies that exhibit a low risk of bias, in order to improve repeatability and comparisons between studies.

Extensor mechanism tendinopathy in patients with lateral patellar maltracking

OBJECTIVE

Patellar maltracking is an important subset of patellofemoral pain syndrome. We hypothesize that maltracking patients have an increased incidence of extensor mechanism dysfunction due to repetitive attempts at stabilization of the patella. Our purpose is to delineate imaging features to identify maltracking patients at risk for extensor mechanism tendinopathy.

MATERIALS AND METHODS

Retrospective review of knee MRIs performed for anterior knee pain over a year was conducted to identify 218 studies with imaging findings of maltracking. The cases were evaluated for the presence and degree of patellar and quadriceps tendinopathy, tibial tuberosity-trochlear groove distance (TT-TG) and the distribution and grade of patellofemoral chondrosis. Cases were compared to 100 healthy, age-matched control knee MRIs.

RESULTS

The mean age of maltracking patients with either patellar or quadriceps tendinosis was 41.2 years versus 48.2 years in the control population (p = 0.037). The TT-TG was significantly higher in maltracking patients with either patellar or quadriceps tendinosis at 16.49 mm versus 14.99 mm (p = 0.006). Maltrackers with isolated lateral patellofemoral chondrosis had a higher mean TT-TG at 17.4 mm versus 15.4 mm (p = 0.007). Extensor mechanism tendinosis was increased in the maltracking population compared to the controls at 57.8% versus 27.3% (p = 0.004).

CONCLUSION

Extensor mechanism tendinosis is more common in the maltracking population and occurs at a younger age. TT-TG distance is significantly increased in patients with extensor mechanism dysfunction and in patients with isolated lateral patellofemoral chondrosis. TT-TG measurement can be used independently to identifying maltrackers who may be at risk for future complications.

The effects of virtual reality training on clinical indices and brain mapping of women with patellofemoral pain: a randomized clinical trial

Background

Virtual reality training (VRT) is a new method for the rehabilitation of musculoskeletal impairments. However, the clinical and central effects of VRT have not been investigated in patients with patellofemoral pain (PFP). To comprehensively assess the effects of VRT on clinical indices and brain function, we used a randomized clinical trial based on clinical and brain mapping assessment.

Methods

Twenty-six women with PFP for more than 6 months were randomly allocated to 2 groups: intervention and control. The intervention consisted of lifestyle education + 8 weeks VRT, in 24 sessions each lasting 40 min of training, whereas the control group just received lifestyle education. The balance was the primary outcome and was measured by the modified star excursion balance test. Secondary outcomes included pain, function, quality of life, and brain function which were assessed by visual analogue scale, step down test and Kujala questionnaire, SF-36, and EEG, respectively. Pre-intervention, post-intervention and follow-up (1 month after the end of the intervention) measurements were taken for all outcome measures except EEG, which was evaluated only at pre-intervention and post-intervention). Analyses of variance was used to compare the clinical outcomes between the two groups. The independent t-test also was used for between group EEG analyses.

Results

Balance score (P < 0.001), function (P < 0.001), and quality of life (P = 0.001) improved significantly at post-intervention and 1 month follow-up in the VRT group compared with the control group. VRT group showed a significantly decreased pain score (P = 0.004). Alpha (P < 0.05) and theta (P = 0.01) power activity also increased in the brain of the VRT group.

Conclusion

This study demonstrated that long term VRT was capable of improving both clinical impairments and brain function in patients with PFP. Therefore, therapists and clinicians can use this method as a more holistic approach in the rehabilitation of PFP.

Trial registration

IRCT, IRCT20090831002391N40. Registered 23 / 10 / 2019.

Effects of a Targeted Exercise Program on Inter-Leg Asymmetries in Patients with Patellofemoral Pain

Patellofemoral pain (PFP) is often associated with impaired muscle strength, flexibility, and stability. It has been suggested that inter-leg asymmetries have an important role in increasing the risk of musculoskeletal injuries, including PFP. Thus, the aim of this study was to identify significant asymmetries and determine the effects of a symmetry targeted exercise program in patients with PFP. Eighteen patients aged 13 to 54 years (24.17 ± 12.52 years) with PFP participated in this study. Strength, flexibility and stability outcomes of the trunk, hip, knee and ankle muscles were assessed. A single-group pretest–posttest design was used to assess changes in inter-leg and agonist–antagonist asymmetries resulting from the 8-week period of the supervised exercise program. Results indicated a significant improvement in inter-leg symmetry regarding bilateral stance in a semi-squat position (p = 0.020, d = 0.61, df = 17) and ankle plantarflexion (p = 0.003, d = 0.32, df = 17) and ankle dorsiflexion strength (p < 0.001, d = 0.46, df = 17). In addition, the ratio of ankle dorsiflexion/plantarflexion (p = 0.036, d = 1.14, df = 17) and hip extension/flexion (p = 0.031, d = 0.94, df = 16) changed significantly during the intervention period. To our knowledge, this was the first study to evaluate inter-leg asymmetries resulting from a period of a supervised exercise program. The results indicate that an exercise program focusing on individual asymmetries may influence specific deficits and contribute to better rehabilitation outcomes.

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.

The Utilization of Core Exercises in Patients With Patellofemoral Pain: A Critically Appraised Topic

Clinical Scenario: Patellofemoral pain (PFP) is characterized by general anterior knee pain around the patella and is one of the most prevalent knee conditions. PFP is challenging to treat due to a wide range of contributing factors and often has chronic, reoccurring symptoms. Traditional treatment focuses on quadriceps and gluteal strengthening with minimal emphasis on deep trunk musculature. Recently, there has been a growing body of literature supporting the beneficial effects of core stability exercises as a treatment option for PFP. Clinical Question: Are core stability exercises coupled with traditional rehabilitation more effective than only traditional rehabilitation techniques for decreasing pain in patients with PFP? Summary of Key Findings: Three articles met the inclusion criteria and investigated core strengthening exercises as a treatment for PFP. Two studies investigated a 4-week exercise protocol and demonstrated a greater decrease in pain when compared to the control group. The third study examined the effects of a 6-week program where both the intervention and control groups resulted in similar reduction of pain. All articles included received a minimum of 6 on the PEDro scale. Clinical Bottom Line: There is evidence that supports core stability exercise protocols coupled with traditional rehabilitation as being more effective in reducing pain in patients with PFP when compared to traditional rehabilitation alone. Strength of Recommendation: The grade of A is recommended based on the Strength of Recommendation Taxonomy.

Lower extremity alignment due to patellofemoral syndrome and dynamic postural balance

STUDY DESIGN

This study is a prospective study.

AIM

Lower extremity malalignment is an important etiologic factor in patellofemoral pain syndrome (PFPS). We hypothesized that lower limb malalignment may affect dynamic balance and physical function. This prospective study was conducted to investigate the relationship between the lower limb alignment and the dynamic balance and physical function in patients with PFPS.

METHODS

The study included 62 individuals with unilateral PFPS. Pain severity was assessed by the numerical pain scale and the pain duration was recorded. Lower extremity bone alignment was evaluated by the lateral distal femoral angle (LDFA) and the medial proximal tibia angle. Dynamic postural balance was assessed by the star excursion balance test. The functional status of the patients was evaluated by the 30-second chair stand test.

RESULTS

The mean duration of the pain was 24.2 ± 31.5 months and the mean pain severity was 8.1 ± 1.4. Although there was a significant difference found between the affected and unaffected LDFA values of lower extremities (p < 0.05), there was no difference found with regard to the dynamic balance values of the lower extremities (p > 0.05). However, significant changes of posterolateral balance were identified at a painful side without causing a postural dynamic imbalance (p < 0.05).

CONCLUSION

In our study, we found a valgus deformity as a deterioration in the lower limb alignment of patients with PFPS which may cause a deterioration of posterolateral balance only. However, no change in postural dynamic balance was observed in the comparison of affected side and unaffected side. Dynamic postural balance has been influenced by many kinematic changes related to lower extremities including pelvis, hip, and ankle. Thus, reciprocal mechanisms in the anatomical structures may compensate the postural balance dynamically.

The immediate effect of lumbopelvic manipulation on knee pain, knee position sense, and balance in patients with patellofemoral pain: A randomized controlled trial

BACKGROUND

Patellofemoral pain (PFP) is a common musculoskeletal disorder. Quadriceps and core muscle neuromuscular control impairments are frequently associated with PFP. Lumbopelvic manipulation (LPM) has been shown to improve quadriceps and core muscle activation and decrease their inhibition, but changes in balance and knee joint position sense (JPS) after this intervention remain unknown.

OBJECTIVE

To determine whether LPM decreases knee pain and JPS error and increases balance performance in patients with PFP.

DESIGN

Randomized controlled trial.

SETTING

Biomechanics laboratory at a rehabilitation science research center.

METHODS

Forty-four patients with PFP participated in this study that randomly divided into two equal groups. One group received LPM and the other received sham LPM (positioning with no thrust) in a single session. At baseline and immediately after the intervention, the outcomes of pain using a visual analog scale, balance using the modified star excursion balance test (mSEBT), and JPS at 20° and 60° of knee flexion using a Biodex dynamometer.

RESULTS

There was a statistically significant improvement in pain, balance control (anterior direction) and JPS in the LPM group immediately after the intervention. In addition, we observed significant differences between groups in pain, balance control (anterior direction) and JPS at 60° of knee flexion immediately after the intervention.

CONCLUSION

A single session of LPM immediately improved balance control, knee JPS, and pain in patients diagnosed with PFP.

CLINICAL REHABILITATION IMPACT

Findings suggest that LPM may be used as a therapeutic tool for immediate improvement of symptoms of PFP. However, more research is needed to determine long term results.

McConnell patellar taping on postural control of women with patellofemoral pain syndrome: randomized clinical trial

Abstract Introduction: The effects of McConnell patellar taping on the postural control of women with patellofemoral pain syndrome (PFPS) are controversial. Objective: To evaluate the effects of McConnell patellar taping on the static one-leg stance postural control and during squatting in women with PFPS. Method: A randomized, blinded clinical trial that comprised 40 women with PFPS, aged between 18 and 35 years. The study sample was allocated to two groups: McConnell patellar taping group (MPTG) and Placebo taping group (PTG). The analysis included the one-leg static support and squat on the lower limb with PFPS. The center of pressure (CoP) displacement parameters recorded by a force platform were analyzed using two-way ANOVA and Cohen’s d. Results: For the static postural control, no significant differences were found between the groups in terms of time or interaction (p>0.05); with small effect size. For the postural control during the one-leg squat, significant differences were found regarding the time of intervention for both groups, with reduced CoP parameters after the application of taping. However, the MPTG demonstrated a large effect size in frequency of oscillation and medium effect size in speed of oscillation, both during the squat exercise. Conclusion: McConnell patellar taping and placebo taping improved postural control during the one-leg squat. It should be observed that the changes and effect sizes determined for the MPTG were significantly higher compared to the PTG, emphasizing its clinical importance in the treatment of individuals with PFPS, during dynamic activities.

Added Value of Gluteus Medius and Quadratus Lumborum Dry Needling in Improving Knee Pain and Function in Female Athletes With Patellofemoral Pain Syndrome: A Randomized Clinical Trial

OBJECTIVE

To compare the effects of exercise therapy alone and exercise therapy plus gluteus medius (GM) and quadratus lumbarum (QL) dry needling on pain and function in female athletes with patellofemoral pain (PFP).

DESIGN

Single-blind randomized controlled trial with follow-up.

SETTING

Physiotherapy clinic.

PARTICIPANTS

Convenience sample of female athletes with PFP (N=40), who were randomly assigned to the exercise therapy (Ex group) or exercise-therapy+dry needling (Ex+DN group) group.

INTERVENTIONS

The Ex group received exercise therapy for 4 weeks, and the Ex+DN group received exercise therapy in combination with dry needling directed at GM and QL trigger points for 4 weeks.

MAIN OUTCOME MEASURES

In all participants, pain intensity, function (Kujala score, modified star excursion balance test, step-down test), and QL and GM pressure pain threshold (PPT) were recorded at baseline and at 4 and 6 weeks after the start of treatment. Analysis of variance (2 groups×3 times) was used to compare within- and between-group differences.

RESULTS

The group versus time interaction effect was significant for all variables (P<.05). Both groups showed significant improvements in pain, function, and PPT at weeks 4 and 6 compared to baseline (P<.05). Between-groups comparisons showed significantly greater improvements in pain, function, and PPT in the Ex+DN group (P<.05).

CONCLUSIONS

Targeting intervention to treat trigger points in the GM and QL muscles combined with exercise therapy had superior beneficial effects compared to exercise alone in managing PFP. Therefore, adding GM and QL muscle dry needling to exercise therapy may be advisable to enhance the effects of PFP rehabilitation.

Effects of Core Neuromuscular Training on Pain, Balance, and Functional Performance in Women With Patellofemoral Pain Syndrome: A Clinical Trial

Objective

The purpose of this study was to determine the effects of core neuromuscular training on pain, balance, and performance in women with patellofemoral pain syndrome (PFPS).

Methods

This randomized single-blind trial was based on a convenience sample of 28 women with unilateral PFPS. All participants were assigned randomly to the intervention or control group with a block randomization method. The control group received routine physical therapy exercise for PFPS. The intervention group received core neuromuscular training in addition to routine physical therapy exercise. The outcome measures evaluated were pain intensity (Visual Analog Scale), function (Kujala patellofemoral questionnaire and step-down performance test), and balance (Y balance test).

Results

In both groups the pain score was significantly lower after treatment (P = .001). The slope of this trend was greater in the intervention group. The Kujala and step-down scores improved significantly after treatment in both groups, although the improvements were greater in the intervention group. The Y balance score improved in all 3 directions after therapy in both groups (P < .05); improvement was significantly greater in the intervention group only in the posteromedial direction (P = .016).

Conclusion

For the group of participants studied, a 4-week core neuromuscular training plus routine physiotherapy exercise was more effective than routine physiotherapy exercise alone for improving pain, balance, and functional performance in individuals with PFPS.

Trunk postural control during unstable sitting differs between patients with patellofemoral pain syndrome and healthy people: A cross-sectional study

BACKGROUND

Patellofemoral pain syndrome (PFPS) is a common orthopedic problem with a high prevalence among young women. Patients with PFPS have altered trunk muscle activity, impaired postural control and greater displacement of the center of pressure (COP) while standing. Training in unstable sitting, by putting more emphasis on trunk sensory receptors, may improve trunk proprioception by minimizing the role of the lower extremities. The aim of this study was to compare trunk postural control in healthy persons and in patients with PFPS.

METHODS

Twenty-one women diagnosed with PFPS and 21 healthy women volunteered to participate in this cross-sectional study. The participants were asked to maintain trunk postural balance on an unstable sitting device, and COP indices of trunk postural control were compared between groups.

RESULTS

All COP indices (e.g., mean anterior-posterior and lateral COP displacement, mean COP velocity and mean area of COP displacement) were significantly increased in participants with PFPS in comparison to healthy controls (P < 0.001). The effect sizes of all the indices were greater than 0.80.

CONCLUSIONS

Trunk postural control is impaired in patients with PFPS, and this finding has clinical implications for rehabilitation in patients with PFPS. Adding seated postural control training to conventional physical therapy management in patients with PFPS may have beneficial effects by emphasizing trunk proprioception while minimizing the role of the lower extremities.

Added Value of Isolated Core Postural Control Training on Knee Pain and Function in Women With Patellofemoral Pain Syndrome: A Randomized Controlled Trial

OBJECTIVES

To evaluate the added value of isolated core postural control training on knee pain and function in women with patellofemoral pain syndrome (PFPS).

DESIGN

Randomized controlled trial.

SETTING

Rehabilitation sciences research center.

PARTICIPANTS

Women (N=33) between 18 and 30 years of age with PFPS were randomly assigned to a control group (n=16) or the experimental group (n=17).

INTERVENTIONS

Participants in both groups received the same stretching and strengthening exercises during 4 weeks (12 sessions 3 days per week). The experimental group also received isolated core postural training with an unstable seat apparatus.

MAIN OUTCOME MEASURES

Center of pressure (CoP) trajectories in sitting postural control, pain intensity, and function were recorded before and after the 4-week intervention period. Functional capacity and pain intensity were reassessed 3 months after the intervention.

RESULTS

After treatment, both groups had significant improvements in pain, function (P<.001), and CoP trajectories in sitting postural control (control group P<.05, experimental group P<.001). Between-group comparisons demonstrated greater improvements in pain, function, and CoP trajectories in the experimental group (P<.001). This group also had significantly greater improvements in pain and Kujala Anterior Knee Pain Scale score at 3-month follow-up compared to the control group (P<.001).

CONCLUSIONS

Adding isolated core postural control training to physiotherapy exercises was associated with significantly greater improvements in pain, function, and CoP trajectories than physiotherapy exercises alone. Therefore, unstable sitting postural control training is potentially useful to enhance rehabilitation management in patients with PFPS.

Patellofemoral pain syndrome in female athletes: A review of diagnoses, etiology and treatment options

Patellofemoral pain syndrome (PFPS) is one of the most common causes of knee pain and is present in females disproportionately more relative to males. PFPS causes tend to be multifactorial in nature and are described in this review. From a review of the current literature, it is clear that there needs to be further research on PFPS in order to better understand the complex etiology of this disorder in both males and females. It is known that females with patellofemoral pain syndrome demonstrate a decrease in abduction, external rotation and extension strength of the affected side compared with healthy patients. Conservative management, including optimizing muscle balance between the vastus medialis and lateralis around the patella along with formal therapy should be the first line of treatment in patients presenting with PFPS. Surgery should be reserved for patients in which all conservative management options have failed. This review aims to guide physicians in accurate clinicaldecision making regarding conservative and surgical treatment options when specifically faced with PFPS in a female athlete. Furthermore, we will discuss the anatomic variants, incidence and prevalence, etiology, diagnosis and treatment of PFPS.

Does the lower extremity alignment affect the risk of falling?

Objectives

This study aims to investigate the effects of knee and foot alignments on the risk of falling.

Patients and methods

Between April 2016 and December 2016, a total of 74 individuals (24 males, 50 females; mean age 32.2±4.9 years; range 18 to 65 years) were included in the study. The knee Q angle and Chippaux-Smirak Index (CSI), Arch Index, and foot progression angle (FPA) evaluated by pedobarography were used for the assessment of the lower extremity alignment. The fall risk was evaluated by the Fall Index, Fourier 56 Index (F56), and Stability Index.

Results

The fall index was found to be correlated with the Q angle, CSI, the Arch index, and FPA (p<0.05). Q angle, Arch Index, and FPA which were explained 40% of the variance of the fall index. The Q angle was correlated with F56 and the stability index at the most position (p<0.05). The CSI was correlated with the F56 and the stability index at two and three positions, respectively (p<0.05); however, the Arch Index and FPA were not correlated with the F56 and Stability Index at any of the eight positions (p>0.05). According to the categorical regression analysis, the Q angle was the most effective on the F56 and Stability Index.

Conclusion

Our study results suggest that lower extremity malalignment increases the risk of falling. We believe that the risk of falling can be decreased by the reduction of these malalingments and, thus, mortality and morbidity associated with the fall can be reduced as well.

Rotational alignment of the knee is different in osteological specimens with and without a large cam deformity of the proximal femur

PURPOSE

We studied a large osteological collection for differences in knee rotation based upon the presence or absence of a large cam deformity of the proximal femur.

METHODS

We obtained 357 matched tibiae and femora from the Hamann-Todd Osteological Collection and measured: femoral head-neck alpha angle, anteroposterior axis (or Whiteside's line) at the distal femur relative to the posterior condylar axis, and position of the tibial tubercle with respect to the posterior condylar axis of the proximal tibia. We then divided these specimens into two groups based upon alpha angle <45° (Group 1, n = 73) or alpha angle >60° (Group 2, n = 122) and performed an independent samples t-test to evaluate for differences in measured parameters between groups using this subset of specimens.

RESULTS

The mean alpha angles in Group 1 and 2 were 40.9° ± 3.3° and 67.0° ± 5.6°, respectively. Whiteside's line was externally rotated with respect to the posterior femoral condylar axis by a mean of 1.8° ± 6.8° in Group 1, vs. 3.0° ± 3.7° in Group 2 (p = 0.03). The tibial tubercle was externally rotated by a mean of 19.4° ± 6.8° in Group 1, versus 16.6° ± 5.1° in Group 2 (p = 0.003).

CONCLUSIONS

Specimens with femoral head-neck alpha angle >60° demonstrated greater external rotation of the distal femur and a more internally-rotated tibial tubercle compared to specimens with an alpha angle <45°. Differences in anatomic characteristics of the knee may play a role in the development of patellofemoral pain in patients with a large cam deformity.

The effects of therapeutic hip exercise with abdominal core activation on recruitment of the hip muscles

Background

Core stabilization has been utilized for rehabilitation and prevention of lower limb musculoskeletal injuries. Previous studies showed that activation of the abdominal core muscles enhanced the hip muscle activity in hip extension and abduction exercises. However, the lack of the direct measurement and quantification of the activation level of the abdominal core muscles during the execution of the hip exercises affect the level of evidence to substantiate the proposed application of core exercises to promote training and rehabilitation outcome of the hip region. The aim of the present study was to examine the effects of abdominal core activation, which is monitored directly by surface electromyography (EMG), on hip muscle activation while performing different hip exercises, and to explore whether participant characteristics such as gender, physical activity level and contractile properties of muscles, which is assessed by tensiomyography (TMG), have confounding effect to the activation of hip muscles in enhanced core condition.

Methods

Surface EMG of bilateral internal obliques (IO), upper gluteus maximus (UGMax), lower gluteus maximus (LGMax), gluteus medius (GMed) and biceps femoris (BF) of dominant leg was recorded in 20 young healthy subjects while performing 3 hip exercises: Clam, side-lying hip abduction (HABD), and prone hip extension (PHE) in 2 conditions: natural core activation (NC) and enhanced core activation (CO). EMG signals normalized to percentage of maximal voluntary isometric contraction (%MVIC) were compared between two core conditions with the threshold of the enhanced abdominal core condition defined as >20%MVIC of IO.

Results

Enhanced abdominal core activation has significantly promoted the activation level of GMed in all phases of clam exercise (P < 0.05), and UGMax in all phases of PHE exercise (P < 0.05), LGMax in eccentric phases of all 3 exercises (P < 0.05), and BF in all phases of all 3 exercises except the eccentric phase of PHE exercise (P < 0.05). The %MVIC of UGMax was significantly higher than that of LGMax in all phases of clam and HABD exercises under both CO and NC conditions (P < 0.001) while the %MVIC of LGMax was significantly higher than UGMax in concentric phase of PHE exercise under NC condition (P = 0.003). Gender, physical activity level and TMG parameters were not major covariates to activation of hip muscles under enhanced core condition.

Conclusions

Abdominal core activation enhances the hip muscles recruitment in Clam, HABD and PHE exercises, and this enhancement is correlated with higher physical activity and stiffer hip muscle. Our results suggest the potential application of abdominal core activation for lower limb rehabilitation since the increased activation of target hip muscles may enhance the therapeutic effects of hip strengthening exercises.