Effects of two gait retraining programs on pain, function, and lower limb kinematics in runners with patellofemoral pain: A randomized controlled trial.

BACKGROUND: Patellofemoral Pain (PFP) is one of the main injuries in runners. Consistent evidence support strengthening programs to modulate symptoms, however, few studies investigated the effects of gait retraining programs. OBJECTIVE: To investigate the effects of two different two-week partially supervised gait retraining programs on pain, function, and lower limb kinematics of runners with PFP. METHODS: Randomized controlled trial. Thirty runners were allocated to gait retraining groups focusing on impact (n = 10) or cadence (n = 10), or to a control group (n = 10). Impact group received guidance to reduce tibial acceleration by 50%, while cadence group was asked to increase cadence by 7.5-10%. The control group did not receive any intervention. Usual and running pain, knee function, and lower limb kinematics (contralateral pelvic drop, hip adduction, knee flexion, ankle dorsiflexion, tibia inclination, and foot inclination) were evaluated before (T0), immediately after the intervention (T2), and six months after the protocol (T24). RESULTS: A significant group x time interaction was found for running pain (p = 0.010) and knee function (p = 0.019). Both programs had greater improvements in running pain compared to no intervention at T24 (Impact x Control-mean difference (MD) -3.2, 95% CI -5.1 to -1.3, p = 0.001; Cadence x Control-MD -2.9, 95% CI -4.8 to -1.0, p = 0.002). Participants of the impact group had greater improvements in knee function compared to no intervention at T2 (Impact x Control-MD 10.8, 95% CI 1.0 to 20.6, p = 0.027). No between-group differences in usual pain and lower limb kinematics were found (p>0.05). CONCLUSION: Compared to no intervention, both programs were more effective in improving running pain six months after the protocol. The program focused on impact was more effective in improving knee function immediately after the intervention. Clinical trial registry number: RBR-8yb47v.

Interaction of Biomechanical, Anthropometric, and Demographic Factors Associated with Patellofemoral Pain in Rearfoot Strike Runners: A Classification and Regression Tree Approach.

BACKGROUND: Patellofemoral pain (PFP) is among the most common injuries in runners. While multiple risk factors for patellofemoral pain have been investigated, the interactions of variables contributing to this condition have not been explored. This study aimed to classify runners with patellofemoral pain using a combination of factors including biomechanical, anthropometric, and demographic factors through a Classification and Regression Tree analysis. RESULTS: Thirty-eight runners with PFP and 38 healthy controls (CON) were selected with mean (standard deviation) age 33 (16) years old and body mass index 22.3 (2.6) kg/m2. Each ran at self-selected speed, but no between-group difference was identified (PFP = 2.54 (0.2) m/s x CON = 2.55 (0.1) m/s, P = .660). Runners with patellofemoral pain had different patterns of interactions involving braking ground reaction force impulse, contact time, vertical average loading rate, and age. The classification and regression tree model classified 84.2% of runners with patellofemoral pain, and 78.9% of healthy controls. The prevalence ratios ranged from 0.06 (95% confidence interval: 0.02-0.23) to 9.86 (95% confidence interval: 1.16-83.34). The strongest model identified runners with patellofemoral pain as having higher braking ground reaction force impulse, lower contact times, higher vertical average loading rate, and older age. The receiver operating characteristic curve demonstrated high accuracy at 0.83 (95% confidence interval: 0.74-0.93; standard error: 0.04; P < .001). CONCLUSIONS: The classification and regression tree model identified an influence of multiple factors associated with patellofemoral pain in runners. Future studies may clarify whether addressing modifiable biomechanical factors may address this form of injury.

Clinical Application of Gait Retraining in the Injured Runner.

Despite its positive influence on physical and mental wellbeing, running is associated with a high incidence of musculoskeletal injury. Potential modifiable risk factors for running-related injury have been identified, including running biomechanics. Gait retraining is used to address these biomechanical risk factors in injured runners. While recent systematic reviews of biomechanical risk factors for running-related injury and gait retraining have been conducted, there is a lack of information surrounding the translation of gait retraining for injured runners into clinical settings. Gait retraining studies in patients with patellofemoral pain syndrome have shown a decrease in pain and increase in functionality through increasing cadence, decreasing hip adduction, transitioning to a non-rearfoot strike pattern, increasing forward trunk lean, or a combination of some of these techniques. This literature suggests that gait retraining could be applied to the treatment of other injuries in runners, although there is limited evidence to support this specific to other running-related injuries. Components of successful gait retraining to treat injured runners with running-related injuries are presented.

Reliability and validity of the One Arm Hop Test and Seated Medicine Ball Throw Test in young adults: A cross-sectional study.

BACKGROUND: Functional performance tests are inexpensive, accessible, and easy to apply tools that can be used to help practitioners in daily decision making process. The purpose of this study was to evaluate the reliability and validity of the One Arm Hop Test (OAHT) and Seated Medicine Ball Throw Test (SBMT) in young adults. METHODS: Cross-sectional study with a sample consisted of 59 young adults. The subjects performed the OAHT and SMBT in two moments separated by seven days and by two examiners. The Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST) was performed at the second moment. The time in OAHT, distance in SMBT, mean number of touches, normalized score, and power of the CKCUEST were measured. Reliability was determined using Intraclass Correlation Coeficient (ICC) and Bland-Altman Plots. Validity was assessed via Pearson's Correlation Coefficient (r) between these tests and CKCUEST. RESULTS: We found good reliability of the OAHT between different raters (dominant limb - ICC = 0.83; non-dominant limb - ICC = 0.80) and moderate reliability between the same rater (dominant limb - ICC = 0.63; non-dominant limb - ICC = 0.62). In the SMBT we found good reliability inter-examiner (ICC = 0.84) and intra-examiner (ICC = 0.77). Low to moderate correlations with the CKCUEST were found (r < 0.70; p < 0.05). CONCLUSIONS: The OAHT and the SMBT show moderate/good reliability intra and inter-examiner, however these tests are poorly correlated with CKCUEST. The SMBT presented higher values of ICC than OAHT. A combination of the SMBT and CKCUEST is recommended in clinical practice.

Effects of gait retraining with focus on impact versus gait retraining with focus on cadence on pain, function and lower limb kinematics in runners with patellofemoral pain: Protocol of a randomized, blinded, parallel group trial with 6-month follow-up.

Patellofemoral pain (PFP) is one of the most prevalent injuries in runners. Unfortunately, a substantial part of injured athletes do not recover fully from PFP in the long-term. Although previous studies have shown positive effects of gait retraining in this condition, retraining protocols often lack clinical applicability because they are time-consuming, costly for patients and require a treadmill. The primary objective of this study will be to compare the effects of two different two-week partially supervised gait retraining programs, with a control intervention; on pain, function and lower limb kinematics of runners with PFP. It will be a single-blind randomized clinical trial with six-month follow-up. The study will be composed of three groups: a group focusing on impact (group A), a group focusing on cadence (group B), and a control group that will not perform any intervention (group C). The primary outcome measure will be pain assessed using the Visual Analog Pain scale during running. Secondary outcomes will include pain during daily activities (usual), symptoms assessed using the Patellofemoral Disorders Scale and lower limb running kinematics in the frontal (contralateral pelvic drop; hip adduction) and sagittal planes (foot inclination; tibia inclination; ankle dorsiflexion; knee flexion) assessed using the MyoResearch 3.14-MyoVideo (Noraxon U.S.A. Inc.). The study outcomes will be evaluated before (t0), immediately after (t2), and six months (t24) after starting the protocol. Our hypothesis is that both partially supervised gait retraining programs will be more effective in reducing pain, improving symptoms, and modifying lower limb kinematics during running compared with the control group, and that the positive effects from these programs will persist for six months. Also, we believe that one gait retraining group will not be superior to the other. Results from this study will help improve care in runners with PFP, while maximizing clinical applicability as well as time and cost-effectiveness.

Effects of Kinesio Taping on peak torque and muscle activity in women with low back pain presenting fears and beliefs related to physical activity.

BACKGROUND: KT is an elastic taping that has been widely used as an adjunct to conventional physiotherapy. The purpose of this study was to evaluate the effects of Kinesio Taping on peak torque, muscle fatigue index and muscle activity of erector spinae in women with low back pain presenting fears and beliefs related to physical activity. METHODS: This is a pilot controlled clinical trial. The subjects were divided into two groups according to the Fear Beliefs Avoidance Questionnaire (FABQ): Group A (Patients with no fears and/or beliefs related to physical activity) and Group B (Patients with fears and/or beliefs related to physical activity). The Kinesio Taping was applied in "I" in order to facilitate erector spinae. An isokinetic dynamometer and a surface electromyography were used to evaluate the outcomes. The evaluations were performed without and with the KT. RESULTS: Sample of 16 women equally divided into two groups with similar characteristics regarding age, weight, height, body mass index, functional capacity and pain levels in the evaluations without and with Kinesio Taping. There were within-groups and between-groups differences in the peak torque (p ≤ .05), with better results in the Group B. No differences were found on muscle fatigue index and muscle activity in both groups (p > .05). CONCLUSION: It was concluded that Kinesio Taping had immediate effects in the peak torque of the erector spinae of women with nonspecific chronic low back pain presenting fears and beliefs related to physical activity. It is suggested that such results occurred by placebo effect. NCT: RBR-5xh3ch.