Effectiveness of exercise therapy in treatment of patients with patellofemoral pain syndrome: systematic review and meta-analysis

Contribution of Shockwave Therapy in the Functional Rehabilitation Program of Patients with Patellofemoral Pain Syndrome

Background: Patellofemoral pain syndrome is a condition with an increasing incidence in recent years, being known as the most common cause of knee pain in adults and adolescents. Undiagnosed and untreated, this condition can worsen over time. The aggravation leads to an increase in the intensity of the pain and the risk of injury, along with an increase in stress on the other joints of the lower limb. The objective of this study was to evaluate the contribution of shockwave therapy to a functional rehabilitation programme for patients with patellofemoral pain syndrome. Materials and Methods: The study was carried out on a group of 64 subjects (32 males and 32 females), aged between 20 and 39 years. The subjects were divided into two groups: 32 subjects who followed a program of functional rehabilitation based on low- and medium-frequency electrotherapy, ultrasound and laser therapy, along with a physical therapy program lasting approximately 3 weeks, and 32 subjects who followed a functional rehabilitation program based on shockwave therapy and specific physical therapy exercises lasting approximately 3 weeks. Results: Following the protocols applied to the two groups, the pain reported by the patients decreased, while the functional parameters of the knee improved, better results being obtained in the group that performed shock wave therapy together with specific physical therapy programs (Cohen Index 5916, p < 0.001). Conclusions: This study indicates that radial shockwave therapy combined with physiotherapy may provide additional benefits for patellofemoral syndrome, including greater pain reduction and improved joint mobility, compared to traditional treatments. However, further research is needed to confirm these findings and their broader clinical applicability.

Effects of neuromuscular electrical stimulation on patellofemoral pain: A randomized controlled trial

INTRODUCTION

Patellofemoral Pain (PFP) is a common dysfunction that can compromise the performance of daily activities. Neuromuscular electrical stimulation (NMES) has been proposed as a complementary tool in the therapeutic approach.

OBJECTIVE

To analyze the effects of adding NMES to therapeutic exercises in women with PFP.

METHODS

Randomized controlled trial involving 34 women with PFP (mean age 23.8 ± 4.1), randomly assigned to two groups: exercises combined with NMES (ESG) and exercises only (ExG). The ExG followed an exercise protocol, while the ESG performed the same exercises combined with NMES. Interventions were performed twice a week for eight weeks. Primary outcome measures included pain and functional disability, while secondary outcomes encompassed electromyographic activity of the quadriceps and hip abductors, along with isokinetic performance. Assessments were performed before the intervention, after 4 and 8 weeks from the start of the protocol and 8 weeks after the conclusion of the treatment.

RESULTS

We did not observe difference between the groups in any of the analyzed variables. Both groups showed a reduction in pain and an improvement in functional disability during intragroup comparisons.

CONCLUSION

A reduction in pain and an improvement in functional disability were observed; however, there was no additional effect of NMES.

TRIAL REGISTRATION

NCT03918863.

The Effect of Lumbopelvic Manipulation for Pain Reduction in Patellofemoral Pain Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Patellofemoral pain syndrome (PFPS) is one of the most common etiologies of knee pain and might be relieved with lumbopelvic manipulation (LPM). This meta-analysis aimed to investigate the effects of LPM on pain reduction in patients with PFPS. Electronic databases were searched from inception to December 2023 for randomized controlled trials (RCTs) investigating the effects of LPM on PFPS. The primary outcome was the change in visual analog or numeric rating scale scores assessing pain. Ten studies comprising 346 participants were included. Significant pain reduction was noted in the LPM group (Hedges' g = -0.706, 95% confidence interval [CI] = -1.197 to -0.214, p = 0.005, I2 = 79.624%) compared with the control group. Moreover, pain relief was more pronounced when LPM was combined with other physical therapies (Hedges' g = -0.701, 95% CI = -1.386 to -0.017, p = 0.045, I2 = 73.537%). No adverse events were reported during the LPM. The LPM appears to be a safe and effective adjuvant therapy for pain reduction in patients with PFPS. Clinicians should consider adding LPM to other physical therapies (e.g., quadriceps muscle strengthening) during the management of these patients.

Effectiveness of Kinesio tape in the treatment of patients with patellofemoral pain syndrome: A systematic review and meta-analysis

OBJECTIVE

To evaluate the clinical effectiveness of the Kinesio tape in the treatment of patellofemoral pain syndrome (PFPS) by meta-analysis.

METHODS

Two investigators independently conducted an electronic literature search to assess the outcomes of intramuscular patches for PFPS. Electronic databases included PubMed, Embase, Web of Science, Cochrane Library, Wanfang Database, Chinese Journal Full Text Database (CNKI), and Wipo Database from November 2023. Extracted inclusion indicators included pain score VAS or NRS, knee function assessment knee pain syndrome (Kujala) score, and knee symptom score Lysholm knee score scale. Data were extracted and then meta-analyzed using Review Manager 5.3 software and Stata 17.0 software.

RESULT

Fourteen studies were included, all of which were randomized controlled studies. The results showed that short-term pain relief was superior in the Kinesio tape (KT) group compared with the control group, with a statistically significant difference in the results (MD = -1.54, 95% CI [-2.32, -0.76], P = .0001); medium-term pain relief was superior in the KT group compared with the control group, with a statistically significant difference in the results (MD = -0.84, 95% CI [-1.50, -0.18], P = .01); long-term pain relief in the KT group was better than the control group, with statistically different results (MD = -0.56, 95% CI [-0.98, -0.13], P < .00001). In contrast, there was no significant difference between the KT group and the control group in the assessment of knee function (MD = -0.98, 95% CI [-4.03, 2.06], P = .03), and there was no significant difference between the KT group and the control group in the Lysholm knee score scale score of knee symptoms (MD = 4.18, 95% CI [-6.70, 15.05], P = .45).

CONCLUSION

Kinesio taping can effectively relieve the pain of PFPS, but has no significant effect on the improvement of knee joint function and symptoms.

The Role of Biofeedback in Patellofemoral Pain Conservative Treatment: A Systematic Review

This paper aims to investigate the effectiveness and the outcomes of the association between different types of biofeedback techniques and therapeutic exercises in the conservative treatment of patellar femoral pain (PFP). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines have been used and followed the Cochrane Handbook for Systematic Reviews of Interventions. Between April and June 2023, the following electronic databases were searched: PubMed, ScienceDirect, BIOMED Central, Cochrane Library, and PEDro. Only randomized controlled trials (RCTs) were selected. Following the search, 414 records were found, and after using strict inclusion and exclusion criteria, 12 RCTs were retrieved to include in this systematic review, assessing 513 patients. The association between biofeedback and therapeutic exercise may be beneficial for pain, function (AKPS), extensor muscle strength, reduction of the dynamic knee valgus and vastus medialis (VM) and vastus lateralis (VL) (EMG) optimization. All these results were valued in the short term. Regarding the intervention type, it was possible to correlate the EMG biofeedback with the benefits of the knee extensor strength and the EMG activity of VM and VL. Conversely, using mirror, verbal, and somesthetic (hands and band) feedback seems to be linked to the reduction of the knee dynamic valgus.

Effect of Tan Tui combined with kinesio taping on the posture control of patients with PFPS: protocol for a randomized controlled trial

BACKGROUND

Patellofemoral pain syndrome (PFPS) is a chronic disease. Its early symptoms are mild and can be relieved by rest after the pain. If there is no effective rehabilitation, it may develop into patellofemoral arthritis. Physiotherapy and appropriate exercise intervention can improve PFPS and postural control during exercise. Tan Tui (TT) is an effective means to improve postural control. Whether combined kinesio taping (KT) can be used as an effective treatment for PFPS patients' recovery has not yet been confirmed.

METHODS/DESIGN

Seventy-two eligible patients with early-stage PFPS will be recruited and randomized into 4 groups: TT + KT group (n = 18), TT + KTp group (n = 18), KT group (n = 18), and CON group (n = 18). The TT + KT group was treated with TT combined with KT intervention; the TT + KTp group was treated with TT and KT placebo technical intervention; the KT group was treated with KT intervention alone; the CON group was treated with routine activities. All 4 groups received 30 min, three times a week, for a total of 6 weeks of intervention training. Measurements will be performed at baseline, mid-intervention (4 weeks), and post-intervention (6 weeks) with visual analog scale/score, (VAS), Knee joint Lysholm function score (Lysholm), UniPedal Stance Test (UST), Star Excursion Balance Test ( SEBT), Relative Peak Torque, (RPT), and Knee joint Position PercePtion (KJPP), to check the maintenance of the effect of any intervention.

DISCUSSION

For the first time in this trial, the impact will be evaluated. If the results are the same as expected, they will provide evidence that TT combined with KT sticking intervention can promote the posture control of patients with early PFPS.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2100051166. Registered on 15 September 2021.

Patello-Femoral Pain Syndrome: Magnetic Resonance Imaging versus Ultrasound

BACKGROUND

Magnetic Resonance Imaging (MRI) and Ultrasound (US) in combination with clinical data could contribute to the diagnosis, staging and follow-up of Patello-Femoral Syndrome (PFS), which often overlaps with other pathologies of the knee.

PURPOSE OF THE STUDY

To evaluate the diagnostic role of MRI and US findings associated with PFS and define the range values of instrumental measurements obtained in pathological cases and healthy controls, the performance of the two methods in comparison, and the correlation with clinical data.

MATERIALS AND METHODS

100 subjects were examined: 60 patients with a high suspicion of PFS at the clinical evaluation and 40 healthy controls. All measurements obtained by MRI and US examination were correlated with clinical data. A descriptive analysis of all measurements was stratified for pathological cases and healthy controls. A Student's t-test for continuous variables was used to compare patients to controls and US to MRI. Logistic regression analysis was applied to test the correlation between MRI and US measurements with clinical data.

RESULTS

Statistical descriptive analysis determined the MRI and US range values of medial patello-femoral distance and the thickness of retinacles and cartilages in pathological cases and healthy controls. In pathological cases, the retinacle results of both increased; the medial appeared to be slightly more increased than the lateral. Furthermore, in some cases, the thickness of the cartilage decreased in both techniques; the medial cartilage was more thinned than the lateral. According to logistic regression analyses, the best diagnostic parameter was the medial patello-femoral distance due to the overlapping results of the US and MRI. Furthermore, all clinical data obtained by different tests showed a good correlation with patello-femoral distance. In particular, the correlation between medial patello-femoral distance and the VAS score is direct and equal to 97-99%, which is statistically significant (p < 0.001), and the correlation with the KOOS score is inverse and equal to 96-98%, which is statistically significant.

CONCLUSIONS

MRI and Ultrasound examination in combination with clinical data demonstrated high-value results in the diagnosis of PFS.

The effect of a supervised online group exercise program on symptoms associated with patellofemoral pain syndrome in women

BACKGROUND

Patellofemoral pain syndrome (PFPS) is one of the musculoskeletal system pathologies frequently encountered especially in women.

OBJECTIVE

The aim of the current study was to compare the efficacy of an online exercise program with a home exercise program including the same exercises, and a control group planned for females with PFPS.

METHODS

The study included 60 females with PFPS aged 33.17 ± 6.84. Participants were randomly divided into 3 groups. One of the groups was given a 6-week home program consisting of evidence-based exercises. Exercises consisting of the same exercises were supervised online to another group. The third group did not receive any intervention. Pain, knee joint range of motion, muscle strength in flexion and extension and hip posterolateral muscle group, patellofemoral joint functionality, quality of life, recurrence of injury and fear of movement were measured at preintervention and postintervention.

RESULTS

Participation in the online supervised exercise group was seen to result in a greater decrease in pain during activity and kinesiophobia, and a greater increase in the quality of life mental health sub-dimension compared to the home exercise group.

CONCLUSION

Online supervised exercise groups could be an alternative telerehabilitation method for exercise programs established for women with PFPS.

Prospective comparative study between knee alignment-oriented static and dynamic balance exercise in patellofemoral pain syndrome patients with dynamic knee valgus

Exercise therapy has been reported as an effective treatment method for patellofemoral pain syndrome (PFPS). However, there is a lack of studies regarding the effectiveness of balance exercise in the treatment of patients with PFPS. This study aimed to prospectively compare changes in proprioception, neuromuscular control, knee muscle strength, and patient-reported outcomes between patients with PFPS treated with knee alignment-oriented static balance exercise (SBE) and dynamic balance exercise (DBE). The participants were divided into 2 groups: 17 knee alignment-oriented SBE group and 19 knee alignment-oriented DBE group. Proprioception was assessed by dynamic postural stability using postural stabilometry. Neuromuscular control and knee muscle strength were measured for acceleration time and peak torque in quadriceps muscle using an isokinetic device. Patient-reported outcomes were evaluated using a visual analog scale for pain and the Kujala Anterior Knee Pain Scale. There was greater improvement in dynamic postural stability (0.9 ± 0.3 vs 1.2 ± 0.5; 95% confidence interval [CI]: 0, 0.6; Effect size: 0.72; P = .021) and quadriceps AT (40.5 ± 14.3 vs 54.1 ± 16.9; 95% CI: 2.9, 24.2; Effect size: 0.86; P = .014) in the DBE group compared to the SBE group. Knee alignment-oriented DBE can be more effective in improving dynamic postural stability and quadriceps muscle reaction time compared with the knee alignment-oriented SBE in PFPS patients with dynamic knee valgus.

IMMEDIATE EFFECTS OF SEMI-CUSTOM INSOLES AND STRUCTURED KNEE SLEEVES ON LOWER EXTREMITY KINETICS AND KINEMATICS IN RECREATIONAL MALE ATHLETES WITH PATELLOFEMORAL PAIN

The aim of this experiment was to provide insight into the immediate influence of both semi-custom insoles and knee sleeves in recreational male runners/athletes suffering from patellofemoral pain and also to explore the association between the extent of patellofemoral pain and psychological wellbeing. Experiment 1 examined 17 male recreational runners with patellofemoral pain, in semi-custom insole and no-insole conditions. Experiment 2 examined 13 male recreational athletes with patellofemoral pain, undertaking run, [Formula: see text] cut and single-leg hop movements in knee sleeve and no-sleeve conditions. In both experiments, motion capture and ground reaction forces were collected, allowing kinetics and three-dimensional kinematics to be calculated alongside patellofemoral joint loading quantified using musculoskeletal modeling. In both experiments, patellofemoral pain symptoms were examined using the KOOS patellofemoral pain subscale and psychological wellbeing using the COOP-WONCA questionnaire. The findings from both experiments showed that pain symptoms significantly predicted psychological wellbeing ([Formula: see text] in experiment 1 and [Formula: see text] in experiment 2). Experiment 1 showed that orthoses significantly reduced tibial internal rotation range of motion (no-[Formula: see text] and [Formula: see text]) whilst also increasing the peak knee adduction moment (no-[Formula: see text][Formula: see text]N[Formula: see text]m/kg and [Formula: see text][Formula: see text]N[Formula: see text]m/kg). The findings from experiment 2 revealed that the knee sleeve reduced the peak patellofemoral force (no-[Formula: see text][Formula: see text]BW and [Formula: see text][Formula: see text]BW) in the run movement and the patellofemoral load rate in the cut movement (no-[Formula: see text][Formula: see text]BW/s and [Formula: see text][Formula: see text]BW/s). Overall, the findings confirm that pain symptoms are predictive of psychological wellbeing in recreational male athletes with patellofemoral pain. Furthermore, the findings suggest that both insoles and knee sleeves may provide immediate biomechanical benefits in recreationally active individuals with patellofemoral pain, although when wearing insoles this may be at the expense of an increased knee adduction moment during running.

Ultrasound investigation into the relationship between hip adduction and the patellofemoral joint

[Purpose] Patellofemoral pain (PFP) is a common musculoskeletal complaint. It has been suggested that hip adduction creates a load on the iliotibial band and causes lateral displacement of the patella (patella tilt). However, data gathered in a previous study were derived from a small sample of males, while the condition predominantly affects females. We assessed the relationship between hip adduction and patellar position with a larger sample size, including males and females. [Participants and Methods] Forty healthy, asymptomatic females and males (age 21.5 ± 1.3 years) were recruited. Their knees were passively flexed by 20°. Using ultrasound, the distance between the lateral edge of the patella and the lateral condyle of the femur was measured in the neutral position and at 20° adduction. [Results] Hip adduction produced a smaller patella-lateral femoral condyle measurement than in the neutral position. The mean difference in the patella-condyle distance between the neutral position and 20° hip adduction was 0.18 cm. No statistically significant difference was found between the right and left limbs, genders, Tegner scores, or BMI of the study participants. [Conclusion] The results of the study showed that hip adduction causes lateral displacement of the patella. Ultrasound is an effective means of assessing patella tilt.

A Systematic Review of Clinical Practice Guidelines for Physical Therapist Management of Patellofemoral Pain

OBJECTIVE

The purpose of this study was to conduct a systematic review to evaluate clinical practice guidelines for the physical therapist management of patellofemoral pain.

METHODS

Five electronic databases (CINAHL, Embase, Medline, Psychinfo, Cochrane Library) were searched from January 2013 to October 2019. Additional search methods included searching websites that publish clinical practice guidelines containing recommendations for physical therapist management of patellofemoral pain. Characteristics of the guidelines were extracted, including recommendations for examination, interventions, and evaluation applicable to physical therapist practice. Quality assessment was conducted using the Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument, applicability of recommendations to physical therapist practice was examined using the AGREE Recommendation Excellence instrument, and convergence of recommendations across guidelines was assessed.

RESULTS

Four clinical practice guidelines were included. One guideline evaluated as higher quality provided the most clinically applicable set of recommendations for examination, interventions, and evaluation processes to assess the effectiveness of interventions. Guideline-recommended interventions were consistent for exercise therapy, foot orthoses, patellar taping, patient education, and combined interventions and did not recommend the use of electrotherapeutic modalities. Two guidelines evaluated as higher quality did not recommend using manual therapy (in isolation), dry needling, and patellar bracing.

CONCLUSION

Recommendations from higher-quality clinical practice guidelines may conflict with routine physical therapist management of patellofemoral pain. This review provides guidance for clinicians to deliver high-value physical therapist management of patellofemoral pain.

IMPACT

This review addresses an important gap between evidence and practice in the physical therapist management of patellofemoral pain.

LAY SUMMARY

If you have kneecap pain, this review offers guidance for your physical therapist to provide examination processes, treatments, and evaluation processes that are recommended by high-quality guidelines.

The Effect of Diacutaneous Fibrolysis on Local and Widespread Hyperalgesia and Muscle Length in Patients With Patellofemoral Pain Syndrome: Secondary Analysis of a Pretest-Posttest Clinical Trial

CONTEXT

Localized and widespread hyperalgesia has been observed in patients with patellofemoral pain. Diacutaneous fibrolysis (DF) has shown to be effective in reducing pain in several musculoskeletal conditions including patellofemoral pain syndrome, but no studies have evaluated the effects of this technique in reducing localized and widespread hyperalgesia.

OBJECTIVE

To assess the effect of DF on the pressure pain threshold and muscle length tests in patients with patellofemoral pain syndrome.

DESIGN

A single-group, pretest-posttest clinical trial.

SETTING

University of Zaragoza.

PARTICIPANTS

Forty-six subjects with patellofemoral pain (20 males and 26 females: age 27.8 [6.9] y).

INTERVENTION

Three sessions of DF.

MAIN OUTCOME MEASURES

Pressure pain threshold using a handheld pressure algometer (4 sites around the knee, on tibialis anterior muscle, and one remote site on the upper contralateral limb); muscle length test of the iliotibial band, rectus femoris, and hamstring muscles; and patient-perceived treatment effect score.

RESULTS

The application of 3 sessions of DF significantly increased the pressure pain threshold in all sites at posttreatment evaluation (P < .001) and at a 1-week follow-up (P < .001). A significant increase in muscle length was also observed at the posttreatment evaluation (P < .001) and 1-week follow-up (P < .001). Ninety-seven percent of the patients reported subjective improvement at posttreatment and at 1-week follow-up.

CONCLUSION

This study found that local and widespread hyperalgesia was significantly reduced after 3 sessions of diacutaneous fibrolysis and at the 1-week follow-up. A significant improvement on muscle length tests was also observed, with high clinical satisfaction among patients.

Osteopathic Manipulative Treatment Versus Exercise Program in Runners With Patellofemoral Pain Syndrome: A Randomized Controlled Trial

CONTEXT

The effects of an exercise program (EP) for the treatment of patellofemoral pain syndrome (PFPS) are well known. However, the effects of osteopathic manipulative treatment (OMT) are unclear.

OBJECTIVE

To evaluate the effects of OMT versus EP on knee pain, functionality, plantar pressure in middle foot (PPMF), posterior thigh flexibility (PTF), and range of motion of hip extension in runners with PFPS.

DESIGN

This is a randomized controlled trial.

SETTING

Human performance laboratory.

PARTICIPANTS

A total of 82 runners with PFPS participated in this study.

INTERVENTIONS

The participants were randomized into 3 groups: OMT, EP, and control group. The OMT group received joint manipulation and myofascial release in the lumbar spine, hip, sacroiliac joint, knee, and ankle regions. The EP group performed specific exercises for lower limbs. The control group received no intervention.

MAIN OUTCOME MEASURES

The main evaluations were pain through the visual analog scale, functionality through the Lysholm Knee Scoring Scale, dynamic knee valgus through the step-down test, PPMF through static baropodometry, PTF through the sit and reach test, and range of motion through fleximetry. The evaluations were performed before the interventions, after the 6 interventions, and at 30-day follow-up.

RESULTS

There was a significant pain decrease in the OMT and EP groups when compared with the control group. OMT group showed increased functionality, decreased PPMF, and increased PTF. The range of motion for hip extension increased only in the EP group.

CONCLUSION

Both OMT and EP are effective in treating runners with PFPS.

Patellofemoral joint loading during the forward and backward lunge

OBJECTIVE

To examine patellofemoral joint (PFJ) loading in two lunge movements: Forward Lunge (FL) and Backward Lunge (BL).

DESIGN

Repeated Measures.

SETTING

University Biomechanics Laboratory.

PARTICIPANTS

20 asymptomatic females.

MAIN OUTCOME MEASURES

Six trials of two lunge movements (FL and BL) to a depth of 75% of leg length were performed. 3-D motion capture and force platforms were used to collect data as input into a musculoskeletal model to determine quadriceps force, PFJ reaction force, PFJ stress, and knee flexion angle.

RESULTS

Multivariate analysis indicated differences in PFJ loading variables and joint angles between the lunge movements (Forward vs. Backward) and phases (Down vs. Up). Quadriceps force, PFJ reaction force, and knee flexion angle were larger in the FL movement and Up phases. PFJ loading rate was greater in the FL movement along with a lower forward trunk tilt.

CONCLUSION

The FL produced greater PFJ loading variables compared to the BL. Further research is needed to examine a population of individuals who have patellofemoral pain (PFP) to see if their symptoms may be reduced when using the BL.

Physical Therapist Management of Anterior Knee Pain

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Effects of a 12-week home exercise therapy program on pain and neuromuscular activity in patients with patellofemoral pain syndrome

INTRODUCTION

The aim of this study is to evaluate the effects of a 12-week home exercise therapy program on pain, function and neuromuscular activity of the vastus medialis and vastus lateralis.

MATERIALS AND METHODS

Fifty patients with patellofemoral pain syndrome were treated with a 12-week online home exercise program. The primary outcomes of pain and function were assessed at the 12-week follow-up using the Visual Analog Scale and Kujala Score, respectively. Secondary outcomes were the muscle onset time and the ratio of vastus medialis and vastus lateralis during different daily activities.

RESULTS

After 12 weeks, patients showed significant (p < 0.05) improvements of 27 points on the Visual Analog Scale and 10 points on Kujala Score. Differences in pre-post comparison regarding both temporal and amplitude-related neurophysiological differences between the vastus medialis and lateralis were only found when the subjects were divided into groups of different electromyographic patterns. Then changes in the pre-post comparison were particularly evident in the patient group with a delayed vastus medialis onset and a lower activity of the vastus medialis compared to the VL.

CONCLUSION

Pain and function improved significantly after a home exercise therapy program in patients with patellofemoral pain syndrome. In addition, patients with a delayed onset or reduced activity of the vastus medialis compared to the vastus lateralis experienced a reduction in this imbalance.

Effects of Trigger Point Dry Needling on Neuromuscular Performance and Pain of Individuals Affected by Patellofemoral Pain: A Randomized Controlled Trial

Purpose

To investigate the effects of trigger point dry needling (TrP-DN) on exercise-induced patellofemoral pain syndrome (PFPS).

Patients and Methods

In this randomized, single-blind, parallel-group trial, 50 patients with PFPS were randomly allocated to the following two groups: the TrP-DN group (n = 25) and the Sham needling group (n = 25). Patients in both groups were asked to perform a stretching exercise of the quadriceps daily after needling. The needling group received a single session of TrP-DN to trigger points (TrPs) in the vastus medialis oblique (VMO), vastus lateralis (VL), and rectus femoris muscles (once a week for 6 weeks), and the Sham group received placebo needling. Visual analogue scale (VAS) for pain intensity and Kujala questionnaire for the functional status were assessed before treatment, 3 and 6 weeks after treatment, and at the 3-month follow-up. The ratio of the myoelectric amplitude of the vastus medialis oblique and vastus lateralis muscles (VMO/VL) was assessed before treatment and 6 weeks after treatment.

Results

There was no significant difference in the general data between the two groups. The VAS scores and Kujala scores in the TrP-DN group were significantly improved and increased at the 3-week treatment visit, 6-week treatment visit, and 3-month follow-up compared to the scores before treatment; and the scores in the Sham group were only significantly improved at the 3-week treatment visit, and 6-week treatment visit. VAS scores in the TrP-DN group were significantly lower and Kujala scores were significantly higher at the 6-week treatment visit and the 3-month follow-up compared to those in the Sham group. The VMO/VL ratio in the TrP-DN group was significantly increased at the 6-week treatment visit compared to that before treatment.

Conclusion

TrP-DN at the quadriceps combined with stretch can reduce the pain, and improves the clinical symptoms and function, the VMO/VL ratio, and the coordination of VMO and VL in patients with PFPS.

Gait Retraining With Real-Time Visual Feedback to Treat Patellofemoral Pain in Adult Recreational Runners: A Critically Appraised Topic

Clinical Scenario: Patellofemoral pain (PFP) is a common knee injury in recreational adult runners, possibly caused by faulty mechanics. One possible approach to reduce this pain is to retrain the runner's gait. Current research suggests that no definitive gold standard treatment for PFP exists. Gait retraining utilizing visual feedback may reduce PFP in both the short and long term. Clinical Question: In adult runners diagnosed with PFP, does gait retraining with real-time visual feedback lead to a decrease in pain? Summary of Key Findings: A literature search was performed; 3 relevant studies utilizing gait retraining with visual feedback, pain level as an outcome measure, and follow-up measures of at least 1 month after the intervention were included. All the included studies reported a decrease in short- and long-term pain for participants following visual feedback gait retraining. In addition, biomechanical measures related to PFP, including peak hip adduction angle and the angle of contralateral pelvic drop, improved after the completion of the intervention. Clinical Bottom Line: There is level 2 evidence supporting the implementation of 8 sessions over 2 weeks of visual feedback gait retraining as a means of treating patients diagnosed with PFP. Based on current available evidence, clinicians should identify faulty mechanics of patients and implement a protocol of increasing real-time visual feedback over the first 4 sessions and decreasing visual feedback over the final 4 sessions. Strength of Recommendation: Level 2.

Patellofemoral Pain

Patellofemoral pain (PFP) is a common musculoskeletal-related condition that is characterized by insidious onset of poorly defined pain, localized to the anterior retropatellar and/or peripatellar region of the knee. The onset of symptoms can be slow or acutely develop with a worsening of pain accompanying lower-limb loading activities (eg, squatting, prolonged sitting, ascending/descending stairs, jumping, or running). Symptoms can restrict participation in physical activity, sports, and work, as well as recur and persist for years. This clinical practice guideline will allow physical therapists and other rehabilitation specialists to stay up to date with evolving PFP knowledge and practices, and help them to make evidence-based treatment decisions. J Orthop Sports Phys Ther. 2019;49(9):CPG1-CPG95. doi:10.2519/jospt.2019.0302.

The Effect of Diacutaneous Fibrolysis on Patellar Position Measured Using Ultrasound Scanning in Patients With Patellofemoral Pain Syndrome

Context: Tightness or lack of flexibility of several muscles of the thigh has been associated with patellofemoral joint pain. A tight iliotibial band can lead to laterally located patella and an abnormal patellar tracking pattern. Diacutaneous fibrolysis (DF) is commonly used to reduce muscle tightness, but no studies have evaluated the effects of this technique in the treatment of patients with patellofemoral pain syndrome. Objective: To assess the effect of DF on patellar position in patients with patellofemoral pain syndrome. Design: A single-group, pretest–posttest clinical trial. Setting: University of Zaragoza. Participants: A total of 46 subjects with patellofemoral pain (20 males, 26 females; age: 27.8 [6.9] y). Intervention: Three sessions of DF. Main Outcome Measures: Patellar position measurement using real-time ultrasound scanning; pain intensity measured with visual analog scale and function measured with the Anterior Knee Pain Scale. Results: The application of 3 sessions of DF significantly increased the patellar position at posttreatment evaluation (P < .001) and at 1-week follow-up (P < .001). There was not a significant difference on patellar position between posttreatment and follow-up measurements (P = .28). There were also a statistically significant decrease in pain and increase in function at posttreatment and at 1-week follow-up measurements (P < .001). Conclusion: This study found that patellar position, pain intensity, and function were significantly improved after 3 sessions of DF and at 1-week follow-up.

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.

Validation of the Arabic version of the Kujala patellofemoral pain scoring system

BACKGROUND

Patellofemoral knee pain is a common cause of anterior knee pain. The Kujala anterior knee pain score is a scoring system for the clinical assessment of disease severity. The purpose of this cross-sectional study was to validate an Arabic translation of the original Kujala anterior knee pain score to assess Arabic-speaking patients with patellofemoral pain syndrome.

METHODS

The Kujala anterior knee pain score was translated into Arabic by a group of native Arabic and native English speakers including orthopedic surgeons, residents, and a medical student. Questionnaires were filled by 127 patients visiting our outpatient department complaining of anterior knee pain diagnosed clinically and after exclusion of other pathologies. Questionnaires were re-filled at least 2 weeks later via phone contact from a member of our team. After exclusions, 97 questionnaires were analyzed for reliability using Cronbach's alpha for the scoring system's internal consistency and intraclass correlation coefficient for test-retest analysis.

RESULTS

The mean score of the questionnaire before the follow-up was 62.38 (±17.78) and 64.02 (±18.47) after the follow-up. The scoring system's internal consistency measured via Cronbach's alpha was 0.824. Average ICC for the scoring system was 0.948 (CI: 0.923-0.965) and for single measures, 0.902 (CI: 0.856-0.933). Further, 94.8% of patients were contacted before initiating physiotherapy. Forty-six of the patients (47.4%) showed improvement in their scores when contacted, 44 patients (45.4%) showed a slight worsening of their scores and seven patients' (7.2%) scores were unchanged.

CONCLUSIONS

The Arabic translation of the Kujala anterior knee pain score is a valid, reliable, useful, and easy-to-interpret scoring system to assess Arabic-speaking patients with patellofemoral pain syndrome.

National Athletic Trainers' Association Position Statement: Management of Individuals With Patellofemoral Pain

OBJECTIVE: 

To present recommendations for athletic trainers and other health care providers regarding the identification of risk factors for and management of individuals with patellofemoral pain (PFP).

BACKGROUND: 

Patellofemoral pain is one of the most common knee diagnoses; however, this condition continues to be one of the most challenging to manage. Recent evidence has suggested that certain risk factors may contribute to the development of PFP. Early identification of risk factors may allow clinicians to develop and implement programs aimed at reducing the incidence of this condition. To date, clinicians have used various treatment strategies that have not necessarily benefitted all patients. Suboptimal outcomes may reflect the need to integrate clinical practice with scientific evidence to facilitate clinical decision making.

RECOMMENDATIONS: 

The recommendations are based on the best available evidence. They are intended to give athletic trainers and other health care professionals a framework for identifying risk factors for and managing patients with PFP.

July 2018 Letter to the Editor-in-Chief

Letter to the Editor-in-Chief of JOSPT as follows: "No Evidence Exists to Support Manual Therapy in Physical Therapy Practice for Patellofemoral Pain" with Authors' Response J Orthop Sports Phys Ther 2018;48(7):598-599. doi:10.2519/jospt.2018.0203.

Effects of Anterior Knee Displacement During Squatting on Patellofemoral Joint Stress

CONTEXT

Squatting is a common rehabilitation training exercise for patellofemoral pain syndrome (PFPS). Patellofemoral joint stress (PFJS) during squatting with more anterior knee displacement has not been systematically investigated.

OBJECTIVE

To compare PFJS during squatting using 2 techniques: squat while keeping the knees behind the toes (SBT) and squat while allowing the knees to go past the toes (SPT).

SETTING

University research laboratory.

PARTICIPANTS

Twenty-five healthy females (age: 22.69 (0.74) y; height: 169.39 (6.44) cm; mass: 61.55 (9.74) kg) participated.

MAIN OUTCOME MEASURES

Three-dimensional kinematic and kinetic data were collected at 180 and 1800 Hz, respectively. A musculoskeletal model was used to calculate muscle forces through static optimization. These muscle forces were used in a patellofemoral joint model to estimate PFJS.

RESULTS

The magnitudes of PFJS, reaction force, and quadriceps force were higher (P < .001) during SPT compared with the SBT technique. Knee flexion, hip flexion, and ankle dorsiflexion angles were reduced when using the SBT technique.

CONCLUSIONS

Findings provide some general support for minimizing forward knee translation during squats for patients that may have patellofemoral pain syndrome.

The influence of dosing on effect size of exercise therapy for musculoskeletal foot and ankle disorders: a systematic review

OBJECTIVE

The purpose of this review was to identify doses of exercise therapy associated with greater treatment effect sizes in individuals with common musculoskeletal disorders of the foot and ankle, namely, achilles tendinopathy, ankle sprains and plantar heel pain.

METHODS

AMED, EMBASE and MEDLINE were searched from 2005 to August 2017 for randomized controlled trials related to exercise for these three diagnoses. The Physiotherapy Evidence Database scale was used for methodological quality assessment. Exercise dosing variables and outcome measures related to pain and function were extracted from the studies, and standardized mean differences were calculated for the exercise groups.

RESULTS

Fourteen studies met the final inclusion. A majority of the studies showed large effects and two small trends were identified. Patients with plantar heel pain may benefit more from a daily home exercise program than two supervised visits per week (SMD=3.82), but this recommendation is based on weak evidence. In achilles tendinopathy, a relationship was also seen when sets and repetitions of eccentric exercise were performed as tolerated (SMD=1.08 for function, -1.29 for pain).

CONCLUSIONS

Session duration, frequency, total number of visits, and overall length of care may all be dosing variables with limited value for determining effective exercise prescription. However, the limited number of studies prevents any definitive conclusions. Further investigation is warranted to improve our understanding of the influence exercise dosing has on treatment effect sizes. Future randomized controlled trials comparing specific exercise dose variables should be conducted to clarify the impact of these variables.

An observational study of Australian private practice physiotherapy consultations to explore the prescription of self-management strategies

OBJECTIVE

The aim of the study was to explore the types of self-management strategies prescribed; the number of strategies and the overall length of time allocated to self-management prescription, by consultation type and by injury location, in physiotherapy consultations.

METHODS

A cross-sectional, observational study of 113 physiotherapist-patient consultations was undertaken. Regression analyses were used to determine whether consultation type and injury location were associated with the number of strategies prescribed and the length/fraction of time spent on self-management.

RESULTS

A total of 108 patients (96%) were prescribed at least one self-management strategy - commonly exercise and advice. The mean length of time spent on self-management was 5.80 min. Common injury locations were the neck (n = 40) and lower back (n = 39). No statistically significant associations were observed between consultation type or injury location for either outcome (number of strategies and the length/fraction of time allocated to self-management prescription).

CONCLUSION

Physiotherapists regularly spend time prescribing self-management strategies such as exercise, advice, and the use of heat or ice to patients receiving treatment linked to a range of injury locations. This suggests that self-management is considered to be an important adjunct to in-clinic physiotherapy. The practice implications of this are that clinicians should reflect on how self-management strategies can be used to maximize patient outcomes, and whether the allocation of consultation time to self-management is likely to optimize patient adherence to each strategy.

Should exercises be painful in the management of chronic musculoskeletal pain? A systematic review and meta-analysis

BACKGROUND

Chronic musculoskeletal disorders are a prevalent and costly global health issue. A new form of exercise therapy focused on loading and resistance programmes that temporarily aggravates a patient's pain has been proposed. The object of this review was to compare the effect of exercises where pain is allowed/encouraged compared with non-painful exercises on pain, function or disability in patients with chronic musculoskeletal pain within randomised controlled trials.

METHODS

Two authors independently selected studies and appraised risk of bias. Methodological quality was evaluated using the Cochrane risk of bias tool, and the Grading of Recommendations Assessment system was used to evaluate the quality of evidence.

RESULTS

The literature search identified 9081 potentially eligible studies. Nine papers (from seven trials) with 385 participants met the inclusion criteria. There was short- term significant difference in pain, with moderate quality evidence for a small effect size of -0.27 (-0.54 to -0.05) in favour of painful exercises. For pain in the medium and long term, and function and disability in the short, medium and long term, there was no significant difference.

CONCLUSION

Protocols using painful exercises offer a small but significant benefit over pain-free exercises in the short term, with moderate quality of evidence. In the medium and long term there is no clear superiority of one treatment over another. Pain during therapeutic exercise for chronic musculoskeletal pain need not be a barrier to successful outcomes. Further research is warranted to fully evaluate the effectiveness of loading and resistance programmes into pain for chronic musculoskeletal disorders.

PROSPERO REGISTRATION

CRD42016038882.

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.

The Relationship of Static Tibial Tubercle-Trochlear Groove Measurement and Dynamic Patellar Tracking

BACKGROUND

The tibial tubercle to trochlear groove (TT-TG) distance is used for screening patients with a variety of patellofemoral joint disorders to determine who may benefit from patellar medialization using a tibial tubercle osteotomy. Clinically, the TT-TG distance is predominately based on static imaging with the knee in full extension; however, the predictive ability of this measure for dynamic patellar tracking patterns is unknown.

PURPOSE

To determine whether the static TT-TG distance can predict dynamic lateral displacement of the patella.

STUDY DESIGN

Cohort study (Diagnosis); Level of evidence, 2.

METHODS

The static TT-TG distance was measured at full extension for 70 skeletally mature subjects with (n = 32) and without (n = 38) patellofemoral pain. The dynamic patellar tracking patterns were assessed from approximately 45° to 0° of knee flexion by use of dynamic cine-phase contrast magnetic resonance imaging. For each subject, the value of dynamic lateral tracking corresponding to the exact knee angle measured in the static images for that subject was identified. Linear regression analysis determined the predictive ability of static TT-TG distance for dynamic patellar lateral displacement for each cohort.

RESULTS

The static TT-TG distance measured with the knee in full extension cannot accurately predict dynamic lateral displacement of the patella. There was weak predictive ability among subjects with patellofemoral pain ( r² = 0.18, P = .02) and no predictive capability among controls. Among subjects with patellofemoral pain and static TT-TG distances 15 mm or more, 8 of 13 subjects (62%) demonstrated neutral or medial patellar tracking patterns.

CONCLUSION

The static TT-TG distance cannot accurately predict dynamic lateral displacement of the patella. A large percentage of patients with patellofemoral pain and pathologically large TT-TG distances may have neutral to medial maltracking patterns.

Effectiveness of Inclusion of Dry Needling in a Multimodal Therapy Program for Patellofemoral Pain: A Randomized Parallel-Group Trial

Study Design Randomized controlled trial. Background Evidence suggests that multimodal interventions that include exercise therapy may be effective for patellofemoral pain (PFP); however, no study has investigated the effects of trigger point (TrP) dry needling (DN) in people with PFP. Objectives To compare the effects of adding TrP DN to a manual therapy and exercise program on pain, function, and disability in individuals with PFP. Methods Individuals with PFP (n = 60) recruited from a public hospital in Valencia, Spain were randomly allocated to manual therapy and exercises (n = 30) or manual therapy and exercise plus TrP DN (n = 30). Both groups received the same manual therapy and strengthening exercise program for 3 sessions (once a week for 3 weeks), and 1 group also received TrP DN to active TrPs within the vastus medialis and vastus lateralis muscles. The pain subscale of the Knee injury and Osteoarthritis Outcome Score (KOOS; 0-100 scale) was used as the primary outcome. Secondary outcomes included other subscales of the KOOS, the Knee Society Score, the International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC), and the numeric pain-rating scale. Patients were assessed at baseline and at 15-day (posttreatment) and 3-month follow-ups. Analysis was conducted with mixed analyses of covariance, adjusted for baseline scores. Results At 3 months, 58 subjects (97%) completed the follow-up. No significant between-group differences (all, P>.391) were observed for any outcome: KOOS pain subscale mean difference, -2.1 (95% confidence interval [CI]: -4.6, 0.4); IKDC mean difference, 2.3 (95% CI: -0.1, 4.7); knee pain intensity mean difference, 0.3 (95% CI: -0.2, 0.8). Both groups experienced similar moderate-to-large within-group improvements in all outcomes (standardized mean differences of 0.6 to 1.1); however, only the KOOS function in sport and recreation subscale surpassed the prespecified minimum important change. Conclusion The current clinical trial suggests that the inclusion of 3 sessions of TrP DN in a manual therapy and exercise program did not result in improved outcomes for pain and disability in individuals with PFP at 3-month follow-up. Level of Evidence Therapy, level 1b. Prospectively registered July 27, 2015 at www.clinicaltrials.gov (NCT02514005). J Orthop Sports Phys Ther 2017;47(6):392-401. doi:10.2519/jospt.2017.7389.

Patellofemoral pain: Challenging current practice - A case report

Patellofemoral pain (PFP) is a common problem in young people, with 1 in 6 suffering at any one time. It is unclear which management approach is the optimal method for treating PFP in the long term, with traditional physiotherapy examination focusing on assessing for specific structural dysfunction. A rationale for a different assessment and treatment approach, one that moves the focus away from a biomedical/tissue pathology model towards one directed at the neurophysiology of pain, has been suggested. The patient was a 21 year old male with a 6 year history of PFP with previous failed physiotherapeutic treatment. He reported previous multiple healthcare practitioners' advice to avoid activities that were painful as reasons for being unable to participate in sporting activities. No specific structural testing was performed, such as specific muscle strength, length, foot position, patella movement and position, or movement patterns. Descriptions of tissue based pathology models of pain, e.g. patella mal-tracking, were actively discouraged and challenged. The patient was taught to perform one uncomfortable/painful exercise as part of his rehabilitation programme twice a day. The patient achieved 80% improvement in his symptoms over 7 appointments and a return to physical activity following a 5 month rehabilitation programme purposively designed to elicit pain by means of gradually exercising and loading the tissues. This case report highlights the need for further research into exercise protocols for patients suffering with PFP based upon neurophysiology models of pain.

Effectiveness of therapeutic physical exercise in the treatment of patellofemoral pain syndrome: a systematic review

[Purpose] The aim of this study was to analyze the effectiveness of conservative treatment of patellofemoral pain syndrome with physical exercise. [Subjects and Methods] A computer-based review conducted of four databases (PubMed, the Cochrane Library, PEDro, and the University Library) was completed based on the inclusion criteria of patellofemoral pain syndrome patients treated with physical exercise methods and examination with self-reported pain and/or functional questionnaires. [Results] The findings of ten clinical trials of moderate to high quality were evaluated to determine the effectiveness of physical exercise as conservative management for patellofemoral pain syndrome. [Conclusion] The intervention programs that were most effective in relieving pain and improving function in patellofemoral pain syndrome included proprioceptive neuromuscular facilitation stretching and strengthening exercises for the hip external rotator and abductor muscles and knee extensor muscles.

Influence of step rate and quadriceps load distribution on patellofemoral cartilage contact pressures during running

Interventions used to treat patellofemoral pain in runners are often designed to alter patellofemoral mechanics. This study used a computational model to investigate the influence of two interventions, step rate manipulation and quadriceps strengthening, on patellofemoral contact pressures during running. Running mechanics were analyzed using a lower extremity musculoskeletal model that included a knee with six degree-of-freedom tibiofemoral and patellofemoral joints. An elastic foundation model was used to compute articular contact pressures. The lower extremity model was scaled to anthropometric dimensions of 22 healthy adults, who ran on an instrumented treadmill at 90%, 100% and 110% of their preferred step rate. Numerical optimization was then used to predict the muscle forces, secondary tibiofemoral kinematics and all patellofemoral kinematics that would generate the measured primary hip, knee and ankle joint accelerations. Mean and peak patella contact pressures reached 5.0 and 9.7MPa during the midstance phase of running. Increasing step rate by 10% significantly reduced mean contact pressures by 10.4% and contact area by 7.4%, but had small effects on lateral patellar translation and tilt. Enhancing vastus medialis strength did not substantially affect pressure magnitudes or lateral patellar translation, but did shift contact pressure medially toward the patellar median ridge. Thus, the model suggests that step rate tends to primarily modulate the magnitude of contact pressure and contact area, while vastus medialis strengthening has the potential to alter mediolateral pressure locations. These results are relevant to consider in the design of interventions used to prevent or treat patellofemoral pain in runners.

Study protocol: a randomised controlled trial comparing the long term effects of isolated hip strengthening, quadriceps-based training and free physical activity for patellofemoral pain syndrome (anterior knee pain)

BACKGROUND

Patellofemoral pain syndrome (PFPS), also known as Anterior Knee Pain, is a common cause of recurrent or chronic knee pain. The etiology is considered to be multifactorial but is not completely understood. At the current time the leading theory is that pathomechanics in the patellofemoral joint leads to PFPS. Traditionally, conservative treatment has focused on improving strength and timing in the quadriceps muscles. In recent years, evidence has been accumulating to support the importance of hip control and strengthening in PFPS. Two recent studies have shown promising results for hip strengthening as an isolated treatment for PFPS. The aim of this randomised controlled trial (RCT) is to compare isolated hip strengthening to traditional quadriceps-based training and a control group with free physical activity.

METHODS/DESIGN

An observer-blinded RCT will be performed. We intend to include 150 patients aged 16-40 years, referred from primary care practitioners to the department of Physical Medicine and Rehabilitation in Kristiansand, Norway for PFPS with more than three months duration. Patients meeting the inclusion criteria will be randomised using opaque sequentially numbered sealed envelopes to one of three groups: isolated hip strengthening, quadriceps based training, or a control group (free physical activity). All groups will receive standardized information about PFPS formulated with the intention to minimize fear avoidance and encourage self-mastery of symptoms. Standardized exercises will be performed under supervision of a study physiotherapist once per week in addition to home training two times per week for a total of six weeks. The primary outcome measure will be the Anterior Knee Pain Score (AKPS) at three and 12 months. Secondary outcome measures will include Visual analogue scale (VAS) for pain, hip abductor and quadriceps strength, the generic EuroQol (EQ-5D), Hopkins Symptom Checklist (HSCL), Knee self-efficacy score and Tampa score for Kinesiophobia.

DISCUSSION

This trial will help to elucidate the role of hip and quadriceps strengthening in the treatment of PFPS. Information as to the role of anxiety and depression, kinesiophobia and self-efficacy will be collected, also as regards prognosis and response to exercise therapy.

TRIAL REGISTRATION

ClinicalTrials.gov reference: NCT02114294.