The effects & mechanisms of increasing running step rate: A feasibility study in a mixed-sex group of runners with patellofemoral pain (original) (raw)

A 10% Increase in Step Rate Improves Running Kinematics and Clinical Outcomes in Runners With Patellofemoral Pain at 4 Weeks and 3 Months

The American Journal of Sports Medicine

Background: Aberrant frontal-plane hip and pelvis kinematics have been frequently observed in runners with patellofemoral pain (PFP). Gait retaining interventions have been shown to improve running kinematics and may therefore be beneficial in runners with PFP. Purpose: To investigate whether a 10% increase in the running step rate influences frontal-plane kinematics of the hip and pelvis as well as clinical outcomes in runners with PFP. Study Design: Case series; Level of evidence, 4. Methods: Runners with PFP underwent a 3-dimensional gait analysis to confirm the presence of aberrant frontal-plane hip and/or pelvis kinematics at baseline. A total of 12 participants with frontal-plane hip and/or pelvis kinematics 1 standard deviation above a reference database were invited to undergo the gait retraining intervention. Running kinematics along with clinical outcomes of pain and functional outcomes were recorded at baseline, 4 weeks after retraining, and 3 months. Gait retraining cons...

Effect of patellofemoral pain on strength and mechanics following an exhaustive run

Purpose: To investigate the effects of an exhaustive run on trunk and lower extremity strength and mechanics in patients with and without patellofemoral pain (PFP), we hypothesized that strength would decrease and mechanics would change after the exhaustive run. Methods: Nineteen subjects with PFP and 19 controls participated (10 men and 9 women per group). Lower extremity and trunk mechanics during running, body mass-normalized strength, and pain assessments before and after an exhaustive run were quantified. A repeated-measures ANOVA was used to assess group differences and exhaustion-related changes (P G 0.05), with t-test post hoc analyses performed when significant interactions were identified (P G 0.0125). Results: Pain significantly increased with the exhaustive run in the PFP group (P = 0.021). Hip strength was reduced after the exhaustive run, more so in those with PFP (abduction: before = 0.384 T 0.08, after = 0.314 T 0.08, P G 0.001; external rotation: before = 0.113 T 0.02, after = 0.090 T 0.02, P G 0.001). Persons with PFP also demonstrated increased knee flexion (before = 41.6-T 5.5-, after = 46.9-T 7.5-, P G 0.001), hip flexion (before = 30.4-T 6.8-, after = 42.5-T 9.7-, P G 0.001), and anterior pelvic tilt (before = 7.2-T 5.1-, after = 13.3-T 6.7-, P = 0.001) after the exhaustive run compared to controls. Trunk flexion increased in both PFP (before = 13.09-T 6.2-, after = 16.31-T 5.3-, P G 0.001) and control (before = 1393-T 4.7-, after = 15.99-T 5.9-, P G 0.001) groups. Hip extension (before = j2.09 T 0.49 NImIkg j1 , after = j2.49 T 0.54 NImIkg j1 , P = 0.002) moments increased only in subjects with PFP. Conclusions: Exhaustive running results in reduced hip strength in subjects with PFP; however, this did not result in changes to hip internal rotation or adduction kinematics. Kinematic and kinetic changes after the exhaustive run are more indicative of compensatory changes to reduce pain. Increasing trunk flexion during running might provide pain relief during running; however, reducing anterior pelvic tilt may also warrant attention during treatment.

Effects of rehabilitation approaches for runners with patellofemoral pain: protocol of a randomised clinical trial addressing specific underlying mechanisms

BMC Musculoskeletal Disorders, 2016

Background: Patellofemoral pain (PFP) is highly prevalent in runners, and often leads to functional limitations and cessation of running. Training errors as well as decreased lower limb strength and control during running have all been associated with PFP. While strengthening and gait retraining are commonly used by clinicians, no randomised clinical trial has compared these modalities in runners with PFP. The primary objective of this randomised clinical trial will be to compare the effects of three rehabilitation programs targeting different key factors on symptoms and functional limitations of runners with PFP. The secondary objective will be to explore the factors leading to clinical improvement. Methods/design: We will conduct a single-blind randomised clinical trial to compare three different 8 week rehabilitation programs: Group 1 will receive education on symptoms management based on training modifications; Group 2 will receive an exercise program targeting lower limb strengthening and control in addition to the education component of Group 1; Group 3 will receive running gait retraining advice as well as the education component of Group 1. Sixty-nine runners with PFP will be recruited and will be seen by independent physiotherapists on five visits through 8 weeks. The primary outcome measure will be symptoms and functional limitations measured by the Knee Outcome Survey-Activities of Daily Living Scale questionnaire at baseline, and at the four, eight and 20 weeks follow-up. Secondary outcomes will include pain level measured using visual analog scales, and running mileage. Lower limb kinematics and kinetics during running, and isometric strength will also be evaluated at baseline and 8 weeks follow-up. The effects of rehabilitation programs on measures of symptoms and functional limitations will be assessed using a 2-way ANOVA (Groups x Time). Regression analyses will be used to identify if changes in running mechanics or strength are determinants of clinical success. Discussion: Studies with a high level of evidence are needed to determine the best rehabilitation interventions for runners with PFP. This randomised clinical trial will be the first to compare programs targeting different key factors linked with PFP. Results may guide clinicians and improve their clinical outcomes when treating runners with PFP.

Lower Extremity Kinetics and Kinematics in Runners with Patellofemoral Pain: A Retrospective Case–Control Study Using Musculoskeletal Simulation

Applied Sciences, 2022

Patellofemoral pain (PFP) is a common atraumatic knee pathology in runners, with a complex multifactorial aetiology influenced by sex differences. This retrospective case–control study therefore aimed to evaluate lower limb kinetics and kinematics in symptomatic and control male and female runners using musculoskeletal simulation. Lower extremity biomechanics were assessed in 40 runners with PFP (15 females and 25 males) and 40 controls (15 females and 25 males), whilst running at a self-selected velocity. Lower extremity biomechanics were explored using a musculoskeletal simulation approach. Four intergroup comparisons—(1) overall PFP vs. control; (2) male PFP vs. male control; (3) female PFP vs. female control; and (4) male PFP vs. female PFP—were undertaken using linear mixed models. The overall (stress per mile: PFP = 1047.49 and control = 812.93) and female (peak stress: PFP = 13.07 KPa/BW and control = 10.82 KPa/BW) comparisons showed increased patellofemoral joint stress indi...

Acute Responses of Strength and Running Mechanics to Increasing and Decreasing Pain in Patients With Patellofemoral Pain

Journal of Athletic Training

Context: Patellofemoral pain (PFP) is typically exacerbated by repetitive activities that load the patellofemoral joint, such as running. Understanding the mediating effects of changes in pain in individuals with PFP might inform injury progression, rehabilitation, or both. Objective: To investigate the effects of changing pain on muscular strength and running biomechanics in those with PFP. Design: Crossover study. Setting: University research laboratory. Patients or Other Participants: Seventeen participants (10 men, 7 women) with PFP. Intervention(s): Each participant completed knee pain-reducing and pain-inducing protocols in random order. The pain-reducing protocol consisted of 15 minutes of transcutaneous electric nerve stimulation (TENS) around the patella. The pain-inducing protocol was sets of 20 repeated single-legged squats (RSLS). Participants completed RSLS sets until either their pain was within at least 1 cm of their pain during an exhaustive run or they reached...

High Eccentric Hip Abduction Strength Reduces the Risk of Developing Patellofemoral Pain Among Novice Runners Initiating a Self-Structured Running Program: A 1-Year Observational Study

The Journal of orthopaedic and sports physical therapy, 2015

Study Design Observational prospective cohort study with 1-year follow-up. Objectives To investigate the relationship between eccentric hip abduction strength and the development of patellofemoral pain (PFP) in novice runners, during a self-structured running regime. Background Recent research indicates gluteal muscle weakness in individuals with PFP. However, current prospective research is limited to evaluation of isometric strength, producing inconsistent findings. Considering hip muscles including gluteus maximus and medius activate eccentrically to control hip and pelvic motion during weight-bearing activities such as running, evaluating the potential link between eccentric strength and PFP risk is needed. Methods 832 novice runners were included at baseline and 629 participants were included in the final analysis. Maximal eccentric hip abduction strength was measured using a handheld dynamometer prior to initiating a self-structured running program. The diagnostic criteria to ...

Assessment of Dynamic Knee Valgus between Lateral Step-Down Test and Running in Female Runners with and without Patellofemoral Pain Using Two-Dimensional Video Analysis

Clinics and Practice

Dynamic knee valgus (DKV) is a frontal plane knee kinematic alteration that has been associated with patellofemoral pain (PFP) in female runners. DKV is commonly assessed in clinical practice by measuring frontal plane knee projection angle (FPPA) during squat tests. However, it remains unclear whether the DKV observed in these tests is similar to or correlates with that observed during running in female runners. The aims of this cross-sectional study were to correlate and compare DKV, by measuring FPPA values, in a lateral step-down (LSD) squat test and running in female runners with and without PFP. A two-dimensional (2D) video analysis of the LSD test and running was carried out for 21 asymptomatic female runners and 17 PFP female runners in order to determine FPPA values. A Pearson correlation test and a factorial ANOVA with Bonferroni post hoc correction were used for statistical analysis. The FPPAs recorded in the LSD test were significantly higher than those recorded during r...

What are causes and treatment strategies for patellar-tendinopathy in female runners?

Journal of Biomechanics, 2008

Patellar-tendinopathy (PT) is a common overuse injury in long distance runners, especially in women. Until today, no definite combinations of clinical, biomechanical, or training variables, or causative factors in the development of PT have been found. This study focused on assessing the differences in biomechanical characteristics between healthy runners (CO) and runners with PT only. We examined a total of 42 women. 21 CO and 21 PT. 3D kinematics of barefoot running was used in the biomechanical setup. Both groups were matched with respect to height and weight. After determining dropouts due to forefoot running, poor quality of data and lack of matching subjects in CO in terms of body height and weight, the final population comprised 24 subjects (CO ¼ 12, PT ¼ 12). Biomechanical evaluations indicate eccentric overloading of the quadriceps muscle group (knee extensors), increased pronation velocity as well as a lack of joint coordination as major etiological factors in the development of PT. We assume that eccentric strengthening of the knee extensors, as well as reduction of pronation velocity through orthotics, proper running shoes, and balance training will help treat and possibly prevent PT. r