Will you get what you want? Treatment goals and expectations of patients with femoroacetabular impingement syndrome regarding physiotherapist-led treatment.

OBJECTIVE: To (i) investigate the goals and expectations of participants enrolled in a clinical trial of physiotherapist-led treatment for femoroacetabular impingement (FAI) syndrome and (ii) explore associations between their expectations and self-reported hip burden and kinesiophobia. METHODS: Data from 150 participants with FAI syndrome who participated in a clinical trial were analysed. Participants described their most important treatment goal and the expectation of achieving this goal throughout physiotherapy treatment. The International Hip Outcome Tool (iHOT-33) subscales were used to assess self-reported hip burden. The Tampa Scale for Kinesiophobia was used to assess kinesiophobia. Participants goals were qualitatively analysed using content analysis. Linear regression was used to explore associations between patient expectations and iHOT and Tampa Scale for Kinesiophobia scores. RESULTS: Participants with FAI syndrome reported goals relating to exercise (52%), improving activities of daily living quality (23%), improving physical function (15%), and reducing pain (10%). Negative expectations regarding physiotherapist-led treatment were reported by 68% of participants. Those with negative expectations reported worse scores for the iHOT-Total score (mean difference = 12 points, 95%CI = [4 to 19]), and iHOT-Symptoms (14 points, [7 to 21]) and iHOT-Social (11 points, [2 to 21]) subscales compared to those with positive expectations. Treatment expectations were not associated with iHOT-Sport, iHOT-Job, and Tampa Scale for Kinesiophobia scores (p > 0.05). CONCLUSION: Patients with FAI syndrome had a generally negative expectation of physiotherapist-led treatment. There was a mismatch between patients' goals and current treatment approaches. Participants with FAI syndrome and negative expectations reported worse quality of life, symptoms, and social concerns than those with positive expectations.

Exploring overweight and obesity beyond body mass index: A body composition analysis in people with and without patellofemoral pain.

BACKGROUND: We compared body mass index (BMI), body fat, and skeletal muscle mass between (1) a mixed-sex nonathletic cohort of people with patellofemoral pain (PFP) and pain-free people, and (2) a nonathletic cohort of people with PFP and pain-free people subgrouped by sex (i.e., men and women with PFP vs. pain-free men and women). METHODS: This cross-sectional study included 114 people with PFP (71 women, 43 men) and 54 pain-free controls (32 women, 22 men). All participants attended a single testing session to assess body composition measures, which included BMI, percentage of body fat (%BFBioimpedance), and skeletal muscle mass (both assessed by bioelectrical impedance analysis), and percentage of body fat (%BFSkinfold) (assessed by skinfold caliper analysis). A one-way univariate analysis of covariance (age and physical activity levels as covariates) was used to compare body composition measures between groups (i.e., PFP vs. pain-free group; women with PFP vs. pain-free women; men with PFP vs. pain-free men). RESULTS: Women with PFP presented significantly higher BMI, %BFBioimpedance, and %BFSkinfold, and lower skeletal muscle mass compared to pain-free women (p ≤ 0.04; effect size : ‒0.47 to 0.85). Men with PFP and men and women combined had no differences in BMI, %BFBioimpedance, %BFSkinfold, and skeletal muscle mass compared to their respective pain-free groups (p > 0.05). CONCLUSION: Our findings indicate that BMI and body composition measures should be considered as part of the evaluation and management of people with PFP, especially in women, who have demonstrated higher BMI and body fat and lower skeletal muscle mass compared to pain-free controls. Future studies should not assess body composition measures in a mixed-sex population without distinguishing men participants from women participants.

Overweight and obesity in young adults with patellofemoral pain: Impact on functional capacity and strength.

PURPOSE: This study aimed to (a) investigate the proportion of overweight/obesity in a cohort of young adults with patellofemoral pain (PFP) and (b) explore the association of body mass index (BMI), body fat, and lean mass with functional capacity and hip and knee strength in people with PFP. METHODS: We included a mixed-sex sample of young adults (18-35 years old) with PFP (n = 100). Measurements for BMI, percentage of body fat, and lean mass (assessed by bioelectrical impedance) were obtained. Functional capacity was assessed by the Anterior Knee Pain Scale, plank test, and single-leg hop test. Strength of the knee extensors, knee flexors, and hip abductors was evaluated isometrically using an isokinetic dynamometer. The proportion of overweight/obesity was calculated based on BMI. The association between BMI, body fat, and lean mass and functional capacity and strength was investigated using partial correlations, followed by hierarchical regression analysis, adjusted for covariates (sex, bilateral pain, and current pain level). RESULTS: A total of 38% of our cohort had their BMI categorized as overweight/obese. Higher BMI was associated with poor functional capacity (ΔR2 = 0.06-0.12, p ≤ 0.001) and with knee flexion strength only (ΔR2 = 0.04, p = 0.030). Higher body fat was associated with poor functional capacity (ΔR2 = 0.05-0.15, p ≤ 0.015) and reduced strength (ΔR2 = 0.15-0.23, p < 0.001). Lower lean mass was associated with poor functional capacity (ΔR2 = 0.04-0.13, p ≤ 0.032) and reduced strength (ΔR2 = 0.29- 0.31, p < 0.001). CONCLUSION: BMI, body fat, and lean mass should be considered in the assessment and management of young people with PFP because it may be detrimental to function and strength.

Body fat and skeletal muscle mass, but not body mass index, are associated with pressure hyperalgesia in young adults with patellofemoral pain.

BACKGROUND: Young adults with patellofemoral pain (PFP) have a high prevalence of being overweight or obese, which is associated with impaired lower limb function and muscle weakness. However, the impact of being overweight or obese on pain sensitivity has not been explored. OBJECTIVES: We investigated the association between body fat, skeletal muscle mass, and body mass index (BMI) with pressure hyperalgesia and self-reported pain in young adults with PFP. METHODS: 114 adults with PFP (24 ± 5 years old, 62% women) were recruited. Demographics and self-reported pain (current and worst knee pain intensity in the previous month - 0-100 mm visual analog scale) were recorded. Body fat and skeletal muscle mass were measured using bioelectrical impedance. Pressure hyperalgesia was measured using a handheld algometer (pressure pain threshold) at three sites: center of patella of the painful knee, ipsilateral tibialis anterior, and contralateral upper limb. The association between body fat, skeletal muscle mass, and BMI with pressure hyperalgesia and self-reported pain were investigated using partial correlations and hierarchical regression models (adjusted for sex, bilateral pain, and symptoms duration). RESULTS: Higher body fat and lower skeletal muscle mass were associated with local, spread, and widespread pressure hyperalgesia (ΔR2=0.09 to 0.17, p ≤ 0.001; ΔR2=0.14 to 0.26, p<0.001, respectively), and higher current self-reported pain (ΔR2=0.10, p<0.001; ΔR2=0.06, p = 0.007, respectively). Higher BMI was associated with higher current self-reported pain (ΔR2=0.10, p = 0.001), but not with any measures of pressure hyperalgesia (p>0.05). CONCLUSION: Higher body fat and lower skeletal muscle mass help to explain local, spread, and widespread pressure hyperalgesia, and self-reported pain in people with PFP. BMI only helps to explain self-reported pain. These factors should be considered when assessing people with PFP and developing their management plan, but caution should be taken as the strength of association was generally low.

Relationship between vastus medialis Hoffmann reflex excitability and knee extension biomechanics during different tasks in women with patellofemoral pain.

BACKGROUND: Impaired knee extension biomechanics and spinal excitability have been reported in women with patellofemoral pain, but their relationship has not been explored. A significant relationship between them could indicate the need for investigating the potential benefits of disinhibitory interventions for women with patellofemoral pain. Thus, this study aimed to investigate the relationship between vastus medialis Hoffmann reflex and (1) maximal isometric, concentric and eccentric knee extensor strength and rate of torque development; (2) knee extensor torque steadiness; and (3) knee extensor moment during functional tasks; in women with patellofemoral pain. METHODS: Spinal excitability of twenty-four participants was assessed by the amplitude of maximal vastus medialis Hoffmann reflex. Knee extensor strength, rate of torque development and torque steadiness were assessed using an isokinetic dynamometer. Knee extensor moment during step-down and stair descent tasks were obtained using a three-dimensional motion analysis system. FINDINGS: A moderate negative relationship was found between vastus medialis Hoffmann reflex and knee extensor torque steadiness (r = -0.35; p = 0.05); whereas a moderate positive relationship was found with maximal isometric knee extensor strength (r = 0.37; p = 0.044). No significant relationships were found between vastus medialis Hoffmann reflex and the other variables. INTERPRETATION: Our findings provide insight on the relationship between spinal excitability and neuromuscular control of maximal and submaximal isometric torque production in women with patellofemoral pain. Conversely, spinal excitability does not seem to be related with dynamic torques and moments of the knee extensors in women with patellofemoral pain.

Patients and clinicians managing patellofemoral pain should not rely on general web-based information.

OBJECTIVE: To evaluate the credibility and accuracy of PFP-specific web-based content. DESIGN: Cross-sectional evaluation of web-based information. METHODS: The study protocol was registered with PROSPERO (CRD42018088671). Two search engines (Google and Bing) were used to search for websites offering information about PFP. Two reviewers assessed the websites for credibility-related and PFP-specific content. PFP-specific content was evaluated according to agreement with current international PFP consensus statements. Based on this, content was rated as (i) Accurate/Clearly described; (ii) Partially accurate/Description lacks clarity; (iii) Inaccurate/Misleading description; or (iv) Not mentioned. RESULTS: After exclusion of duplicates, forty online websites were included in our analyses. 43% of websites did not mention their source of information, and 48% did not mention if the source material was peer-reviewed. Misleading/inaccurate information was most commonly found in the definition of PFP (20% websites) and clinical examination (15%). Twenty-two percent of websites recommended surgery as treatment. The item most frequently rated as accurate/clearly described was PFP terminology (87.5%). CONCLUSION: This study highlights missing, inaccurate or poorly described web-based PFP information. Due to the commonality of PFP and potential for improving self-management, there is an urgent need to develop more accurate and comprehensive web-based patient education resources for PFP.

Patient Education for Patellofemoral Pain: A Systematic Review.

OBJECTIVE: To evaluate the effect of education interventions compared with any type of comparator on managing patellofemoral pain (PFP). DESIGN: Intervention systematic review. PROSPERO identifier: CRD42018088671. LITERATURE SEARCH: MEDLINE, Embase, CINAHL, and Web of Science were searched for studies evaluating the effect of education on clinical and functional outcomes in people with PFP. STUDY SELECTION CRITERIA: Two reviewers independently assessed studies for inclusion and quality. We included randomized controlled trials on PFP where at least 1 group received an education intervention (in isolation or in combination with other interventions). DATA SYNTHESIS: Available data were synthesized via meta-analysis where possible; data that were not appropriate for pooling were synthesized qualitatively. Interpretation was guided by the Grading of Recommendations Assessment, Development and Evaluation approach. RESULTS: Nine trials were identified. Low-credibility evidence indicated that health education material alone was inferior to exercise therapy for pain and function outcomes. Low- and very low-credibility evidence indicated that health professional-delivered education alone produced outcomes similar to those of exercise therapy combined with health professional-delivered education for pain and function, respectively. CONCLUSION: Health professional-delivered education may produce similar outcomes in pain and function compared to exercise therapy plus health professional-delivered education in people with PFP. J Orthop Sports Phys Ther 2020;50(7):388-396. Epub 29 Apr 2020. doi:10.2519/jospt.2020.9400.

Kinesiophobia, but not strength is associated with altered movement in women with patellofemoral pain.

BACKGROUND: Evidence indicates the presence of both kinesiophobia and knee extension strength deficits in women with patellofemoral pain (PFP). Both impairments may contribute to apparent compensatory gait patterns including reduced cadence and peak knee flexion during stair negotiation. RESEARCH QUESTION: Is kinesiophobia or knee extension strength associated with movement pattern in women with patellofemoral pain? METHODS: Forty women with PFP were assessed with three-dimensional kinematic analyses during stair descent; isokinetic dynamometry of the knee extensors (isometric, concentric and eccentric); and the Tampa scale for kinesiophobia. Pearson coefficients were calculated to determine relationship among variables. RESULTS: Kinesiophobia correlated significantly with cadence (r = -0.62, p < 0.001), and peak knee flexion (r = -0.76, p < 0.001). No significant correlations were found between any knee extensor strength variables and kinematics (cadence or peak knee flexion); or kinesiophobia (p > 0.05). SIGNIFICANCE: Findings of this study could suggest addressing strength impairments alone may not adequately address kinesiophobia and movement pattern impairments in women with PFP. However, high-quality randomised controlled trials are needed to test this assumption. Further value may be added if currently evidence-based knee strengthening exercise is combined with education and/or graded exposure to address kinesiophobia, and consideration to gait retraining to address altered movement patterns at the knee.

What are the clinical implications of knee crepitus to individuals with knee osteoarthritis? An observational study with data from the Osteoarthritis Initiative.

BACKGROUND: Crepitus is a common clinical feature of knee osteoarthritis. However, the importance of crepitus in the overall clinical presentation of individuals with knee osteoarthritis is unknown. OBJECTIVE(S): (A) To compare function, pain and quality of life between individuals with knee osteoarthritis with and without crepitus; (B) to compare whether individuals with knee osteoarthritis in both knees, but crepitus in just one, differ in terms of function pain, and knee strength. METHODS: Setting: Observational study. PARTICIPANTS: (A) A total of 584 participants with crepitus who had the same Kellgren-Lawrence grade on both knees were matched for gender, body mass index and Kellgren-Lawrence grade to participants without crepitus on both knees. (B) 361 participants with crepitus in only one knee and with the same Kellgren-Lawrence grade classification on both knees were included. MAIN OUTCOME MEASURE(S): A - Self-reported function, pain, quality of life, 20-m walk test and chair-stand test. B -Knee extensor and flexor strength, self-reported function and pain. RESULTS: A - Individuals with crepitus had lower self-reported function, quality of life and higher pain compared to those without crepitus (3-11%; small effect=0.17-0.41, respectively). No difference was found in objective function between groups. B - Self-reported function was lower in the limb with crepitus compared to the limb without crepitus (15%; trivial effect=0.09). No difference was found in pain and knee strength between-groups. CONCLUSION(S): Individuals with knee osteoarthritis and knee crepitus have slightly lower self-reported physical function and knee-related quality of life (small or trivial effect). However, the presence of knee crepitus is not associated with objective function or knee strength.

Patellar Tendon Reflex and Vastus Medialis Hoffmann Reflex Are Down Regulated and Correlated in Women With Patellofemoral Pain.

OBJECTIVES: The aims of this study were threefold: (1) to compare the amplitude of patellar tendon reflex (T-reflex) between women with patellofemoral pain (PFP) and pain-free controls; (2) to compare the amplitude of vastus medialis Hoffmann reflex (VM H-reflex) between women with PFP and pain-free controls; (3) to investigate the association between the amplitude of patellar T-reflex and VM H-reflex in women with PFP and pain-free controls. DESIGN: Cross-sectional observational study. SETTING: Laboratory of biomechanics and motor control. PARTICIPANTS: Thirty women with PFP and 30 pain-free women aged 18 to 35 years (N=60). MAIN OUTCOME MEASURES: Peak-to-peak amplitudes of maximal VM H-reflex (elicited via electrical stimulation on the femoral nerve) and patellar T-reflex (elicited via mechanical percussion on the patellar tendon) were estimated. RESULTS: Women with PFP had significant lower amplitude of patellar T-reflex (mean difference=0.086; 95% confidence interval=0.020 to 0.151; P=.010; moderate effect) and VM H-reflex (mean difference=0.150; 95% confidence interval =0.073 to 0.227; P<.001; large effect) compared to pain-free controls. The VM H-reflex was strongly correlated with patellar T-reflex in both PFP group (r=0.66; P<.001) and control group (r=0.72; P<.001). CONCLUSIONS: As the T-reflex is easier to perform than H-reflex assessments in a clinical setting, it represents a feasible option to assess the impaired excitability of the stretch reflex pathway associated with PFP.

Knee crepitus is not associated with the occurrence of total knee replacement in knee osteoarthritis - a longitudinal study with data from the Osteoarthritis Initiative.

OBJECTIVE(S): To investigate whether the presence of knee crepitus is associated with the occurrence of total knee replacement (TKR), quality of life and deficits in physical function at long-term. METHODS: Setting - This observational study uses longitudinal data (up to 4-year follow-up) from the Osteoarthritis Initiative (OAI). Participants - 4566 participants. Main Outcome Measure(s) - Logistic regression models were used to test if baseline knee crepitus is associated with the occurrence of TKR. Linear mixed models with adjustment for confounding variables (age, gender, BMI and Kellgren-Lawrence grade) were used to test the association between baseline knee crepitus and longitudinal changes in the pain, self-reported physical function, quality of life and performance-based function. RESULTS: The presence of knee crepitus at baseline does not predict the occurrence of TKR at 36 months (p=0.58 and 0.67 for right and left knees, respectively). The crepitus group presented a slightly knee extension strength decline from baseline to 48 months (p=0.03 for the right and 0.01 for the left knee; between group difference=2% for both right [95%CI=-0.12; -0.01] and left knees [95%CI=-0.13; -0.02]). CONCLUSION: The presence of knee crepitus is not associated with the occurrence of TKR in the following three years. Knee crepitus is associated with slightly declines in knee extension strength, but this does not seem to affect physical function and quality of life at long-term.

Relationship between knee abduction moment with patellofemoral joint reaction force, stress and self-reported pain during stair descent in women with patellofemoral pain.

BACKGROUND: Increased external knee abduction moment has been proposed as a risk factor for patellofemoral pain. This alteration is thought to be associated with elevated patellofemoral joint reaction force and stress, however these relationships remain poorly explored. Therefore, this study aimed at comparing knee abduction moment parameters (peak, rate of moment development and impulse), patellofemoral joint reaction force and stress of women with patellofemoral pain and pain-free controls during stair descent; and investigating the relationship among these variables with self-reported pain. METHODS: Kinetic data was obtained by inverse-dynamics equations and a previously reported algorithmic model was used to determine patellofemoral joint reaction force and stress. Participants' worst pain in the last month and pain level during stair descent were evaluated using a visual analogue scale. FINDINGS: Women with patellofemoral pain presented higher peak, rate of moment development and impulse of the external knee abduction moment, patellofemoral joint reaction force and stress (p = 0.005 to 0.04, effect size = 0.52 to 0.96) during stair descent than pain-free controls. Only knee abduction moment impulse presented positive moderate correlations with worst pain level in the last month (r = 0.53, p < 000.1), pain level during stair descent (r = 0.33, p = 0.042), patellofemoral joint reaction force (r = 0.65, p < 000.1) and stress (r = 0.58, p < 000.1). INTERPRETATION: These findings indicate that strategies aimed at decreasing external knee abduction moment impulse could reduce the load over the patellofemoral joint and improve pain of women with patellofemoral pain.

Knee crepitus is prevalent in women with patellofemoral pain, but is not related with function, physical activity and pain.

OBJECTIVES: (i) To assess the reliability of knee crepitus measures, (ii) to investigate the association between knee crepitus and PFP; (iii) to investigate the relationship between knee crepitus with self-reported function, physical activity and pain. DESIGN: Cross-sectional. SETTING: Laboratory-based study. PARTICIPANTS: 165 women with PFP and 158 pain-free women. MAIN OUTCOME MEASURES: Knee crepitus test, anterior knee pain scale (AKPS) and self-reported worst knee pain in the last month, knee pain after 10 squats and knee pain after 10 stairs climbing. RESULTS: Knee crepitus clinical test presented high reliability Kappa value for PFP group was 0.860 and for pain-free group was 0.906. There is a significantly greater proportion of those with crepitus in the PFP group than in the pain-free group (OR = 4.19). Knee crepitus had no relationship with function (rpb = 0.03; p = 0.727), physical activity level (rpb = 0.010; p = 0.193), worst pain (rpb = 0.11; p = 0.141), pain climbing stairs (rpb = 0.10; p = 0.194) and pain squatting (rpb = 0.02; p = 0.802). CONCLUSION: Women who presents knee crepitus have 4 times greater odds to be in a group with PFP compared to those who do not. However, knee crepitus has no relationship with self-reported clinical outcomes of women with PFP.

Association between increase in vertical ground reaction force loading rate and pain level in women with patellofemoral pain after a patellofemoral joint loading protocol.

BACKGROUND: The etiology of patellofemoral pain (PFP) is thought to be the result of increased patellofemoral joint (PFJ) load and aberrant lower extremity mechanics, including altered vertical ground reaction forces (VGRF). However, few studies have investigated the association between an increase in pain and VGRF loading rates in the context of PFP. Thus, this study aimed to investigate the immediate effects of PFJ loading on pain and VGRF loading rate, and to see if there is a link between modification of both pain and VGRF loading rate during stair negotiation. METHODS: Thirty-four women with PFP underwent VGRF analysis during stair negotiation under two conditions: with (condition 2) and without (condition 1) being previously submitted to a PFJ loading protocol in order to or not to exacerbate their knee pain, respectively. RESULTS: The VGRF loading rates were significantly higher in condition 2 (Mean ± standard deviation (SD)=4.0±0.6N/s) compared to condition 1 (Mean±SD=3.6±0.5N/s) during stair ascent and during stair descent (Mean±SD: condition 1=6.3±1.1N/s; condition 2=7.0±1.4N/s). In addition, VGRF loading rates were higher during stair descent compared to stair ascent in both conditions. There were significant correlations between the increase in pain and VGRF loading rate during both tasks. CONCLUSION: There seemed to be an important relation between the increase in pain and VGRF loading rates in women with PFP. Based on these findings, interventions aimed at reducing VGRF loading rates are important in the context of PFP.

Which is the best predictor of excessive hip internal rotation in women with patellofemoral pain: Rearfoot eversion or hip muscle strength? Exploring subgroups.

BACKGROUND: Patellofemoral pain (PFP) has been linked to increased patellofemoral joint stress as a result of excessive hip internal rotation. Lower hip strength and/or excessive rearfoot eversion have been used to explain such altered movement pattern; however, it is unknown which one is the best predictor of excessive hip internal rotation. RESEARCH QUESTION: To investigate if peak rearfoot eversion and/or peak concentric hip abductor strength can predict peak hip internal rotation during stair ascent in women with PFP. METHODS: This cross-sectional study included thirty-seven women with PFP which underwent three-dimensional kinematic analysis during stair ascent and hip abductor strength analysis in an isokinetic dynamometer. A forced entry linear regression model analysis was carried out to determine which independent variables present the best capability to predict the hip internal rotation. RESULTS: Peak concentric hip abductor strength significantly predicted peak hip internal rotation during stair ascent (R2 = 0.27, p = 0.001). Peak rearfoot eversion did not predict peak hip internal rotation during stair ascent (R2 < 0.01, p = 0.62). A Post-hoc analysis was conducted to explore if a subgroup with excessive rearfoot eversion would predict hip internal rotation. Based on a previous reported cut-off point, 48.6% of the participants were classified as excessive rearfoot eversion. For the subgroup with excessive rearfoot eversion, peak concentric hip abductor strength and peak rearfoot eversion significantly predicted peak hip internal rotation during stair ascent (R2 = 0.26, p = 0.02; R2 = 0.42, p = 0.003, respectively). For non-excessive rearfoot eversion subgroup, peak concentric hip abductor strength significantly predicted peak hip internal rotation during stair ascent (R2 = 0.53; p < 0.001); and peak rearfoot eversion did not (R2 = 0.01; p = 0.65). SIGNIFICANCE: Findings indicate that hip muscle strength seems to be related with hip internal rotation in all women with PFP. Rearfoot eversion seems to be related with hip internal rotation only in a subgroup with excessive rearfoot eversion.

What interventions can improve quality of life or psychosocial factors of individuals with knee osteoarthritis? A systematic review with meta-analysis of primary outcomes from randomised controlled trials.

OBJECTIVE: To systematically review evidence of primary outcomes from randomised controlled trials (RCTs) examining the effect of treatment strategies on quality of life (QoL) or psychosocial factors in individuals with knee osteoarthritis (OA). DESIGN: Systematic review with meta-analysis. DATA SOURCES: Medline, Embase, SPORTDiscus, the Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Web of Science were searched from inception to November 2017. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: We included RCTs investigating the effect of conservative interventions on QoL or psychosocial factors in individuals with knee OA. Only RCTs considering these outcomes as primary were included. RESULTS: Pooled data supported the use of exercise therapy compared with controls for improving health-related and knee-related QoL. There was limited evidence that a combined treatment of yoga, transcutaneous electrical stimulation and ultrasound may be effective in improving QoL. Limited evidence supported the use of cognitive behavioural therapies (with or without being combined with exercise therapy) for improving psychosocial factors such as self-efficacy, depression and psychological distress. SUMMARY/CONCLUSION: Exercise therapy (with or without being combined with other interventions) seems to be effective in improving health-related and knee-related QoL or psychosocial factors of individuals with knee OA. In addition, evidence supports the use of cognitive behavioural therapies (with or without exercise therapy) for improving psychosocial factors such as self-efficacy, depression and psychological distress in individuals with knee OA. PROSPERO REGISTRATION NUMBER: CRD42016047602.

Higher pain level and lower functional capacity are associated with the number of altered kinematics in women with patellofemoral pain.

This study investigated whether women with patellofemoral pain (PFP) present kinematic alterations in proximal, local, and distal factors simultaneously, and determined the association between the number of kinematic alterations, pain level, and functional status. A three-dimensional motion analysis system was used to analyze the peak hip adduction, peak knee flexion, and peak rearfoot eversion, addressing the proximal, local, and distal factors, respectively, in fifty women. Functional status and pain level were assessed using the anterior knee pain scale (AKPS) and a visual analogic scale. Receiver operating characteristic curves were calculated to identify participants with and without kinematic alterations and the number of them was obtained for each participant. Associations between the number of kinematic alterations, pain level, and AKPS score were determined by the Pearson correlation. Results showed that 52% of women with PFP presented at least two kinematic alterations of which 24% were local/proximal, 16% local/distal, and 12% proximal/distal. Three kinematic alterations were found in 48% of the women with PFP. A strong positive correlation was found between the number of kinematic alterations and pain (r=0.78; p<0.001). A strong negative correlation was found between the number of altered kinematics and functional status (r=-0.79; p<0.001). Findings revealed that women with PFP presented at least two kinematic alterations and a higher number of kinematic alterations was associated with higher pain levels and lower functional status. Clinicians should carefully assess movement pattern of women with PFP as it could indicate a more severe condition, which is associated with a poor prognosis.

Is quadriceps H-reflex excitability a risk factor for patellofemoral pain?

Patellofemoral pain (PFP) is one of the most common conditions in orthopedic practice while recent evidence has suggested that it may be a predisposing factor to patellofemoral osteoarthritis. In addition to biomechanical alterations associated with the pathomechanisms underlying PFP, the investigation of neurophysiological alterations has provided novel information in the understanding of the pathophysiology of PFP. For instance, women with PFP present lower amplitude of the vastus medialis (VM) H-reflexes compared to pain-free controls, which suggests that the excitability of spinal reflexes might be a promising tool for discriminating woman with PFP in clinical practice. However, the cross-sectional design of the current research does not inform whether the reduced excitability predisposes to or is the consequence of PFP. Therefore, two hypotheses can be raised: (1) the reduction in excitability of the α-motoneurons is a risk factor for PFP; Or, (2) the reduction in H-reflex excitability is a consequence of PFP due to pain. If the former hypothesis is proven correct, it may help in the early identification of individuals with PFP. If the latter, it may help understand the reduced excitability as a consequence of the long-term pain, which may be interfering in the recovery of individuals with PFP in a long-term basis. In addition, exploring such hypotheses may have direct rehabilitative and prevention implications for PFP and its putative progression to knee osteoarthritis.

Vastus Medialis Hoffmann Reflex Excitability Is Associated With Pain Level, Self-Reported Function, and Chronicity in Women With Patellofemoral Pain.

OBJECTIVE: To determine the association between the amplitude of vastus medialis (VM) Hoffmann reflex (H-reflex) and pain level, self-reported physical function, and chronicity of pain in women with patellofemoral pain (PFP). DESIGN: Cross-sectional study. SETTING: Laboratory of biomechanics and motor control. PARTICIPANTS: Women diagnosed with PFP (N=15) aged 18 to 35 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Data on worst pain level during the previous month, self-reported physical function, and symptom duration (chronicity) were collected from the participants. Maximum evoked responses were obtained by electrical stimulation applied to the femoral nerve and peak-to-peak amplitudes of normalized maximal H-reflexes (maximal Hoffmann reflex/maximal motor wave ratios) of the VM were calculated. A Pearson product-moment correlation matrix (r) was used to explore the relations between the amplitude of VM H-reflex and worst pain during the previous month, self-reported function, and chronicity of pain. RESULTS: Strong negative correlations were found between the amplitude of VM H-reflex and worst pain in the previous month (r=-.71; P=.003) and chronicity (r=-.74; P=.001). A strong positive correlation was found between the amplitude of VM H-reflex and self-reported physical function (r=.62; P=.012). CONCLUSIONS: The strong and significant relations reported in this study suggest that women with PFP showing greater VM H-reflex excitability tend to have lower pain, better physical function, and more recent symptoms. Therefore, rehabilitation strategies designed to increase the excitability of the monosynaptic stretch reflex should be considered in the treatment of women with PFP if their effectiveness is demonstrated in future studies.