The relationship between supination resistance and the kinetics and kinematics of the foot and ankle during gait.

BACKGROUND: Clinical tests of foot posture and mobility are not strongly related to the dynamic kinematics of the foot during gait. These measures may be more directly related to foot and ankle kinetics. The supination resistance test (SRT) is a clinical test that may more directly measure forces acting on the weightbearing foot to provide clinicians with insight about the loading of foot structures. RESEARCH QUESTION: What is the relationship between the SRT in relaxed calcaneal stance and in single-leg-stance and the kinetics and kinematics of the foot and ankle during gait? METHODS: 10 healthy adults between the ages of 18 and 65 were recruited to participate in this study. Three-dimensional motion analysis was performed using the Oxford Foot Model during gait. The results of the SRT were compared with peak midfoot and ankle joint moments, power generation and absorption, joint angles, and peak angular velocities and accelerations. Correlation coefficients were calculated to assess the strength of relationships between these variables and the SRT. RESULTS: The SRT demonstrated significant relationships with several variables. In relaxed calcaneal stance, the SRT was inversely related to maximum midfoot pronation moments (r = -0.51), maximum midfoot plantarflexion moments (rho = -0.71), and peak midfoot power generation (r = -0.61). In single-leg-stance, the SRT was significantly related to maximum midfoot plantarflexion moments (rho = -0.55) and peak midfoot power generation (r = -0.47). SIGNIFICANCE: The SRT is significantly associated to several kinetic variables that quantify midfoot loading during gait. Interventions that decrease supination resistance may have the potential to increase midfoot power generation.

Concurrent validity of pain scales in individuals with myofascial pain and fibromyalgia.

OBJECTIVE: Clinicians and researchers often use the numeric pain rating scale (NPRS) and visual analog scale (VAS) to measure and track pain in individuals with myofascial pain syndrome (MPS) and fibromyalgia (FM). The VAS is often used as a reference standard in chronic pain research. To date, no studies have specifically measured the concurrent validity of the NPRS and VAS in these individuals. The purpose of this investigation was to determine the concurrent validity of the NPRS when compared to the reference standard VAS in patients with MPS and FM. METHODS: This investigation explored the concurrent validity of the NPRS and VAS in sixty participants with MPS (N = 30) and FM (N = 30). All participants underwent one day of testing using the American College of Rheumatology criteria for classifying FM. For each tender point (18-total), participants graded tenderness using the NPRS and VAS. RESULTS: An excellent relationship was found between the NPRS and VAS for the MPS group (rho≥0.81, 95% CI 0.79-0.85, p < 0.001) and the FM group (rho ≥0.96, 95% CI 0.92-0.97, p < 0.001). CONCLUSION: The results of this study suggest that the NPRS has good concurrent validity with the referenced standard VAS among individuals with MPS and FM.

Predicting Musculoskeletal Injury in National Collegiate Athletic Association Division II Athletes From Asymmetries and Individual-Test Versus Composite Functional Movement Screen Scores.

CONTEXT: Functional Movement Screen (FMS) scores of ≤14 have been used to predict injury in athletic populations. Movement asymmetries and poor-quality movement patterns in other functional tests have been shown to predict musculoskeletal injury (MSI). Therefore, movement asymmetry or poor-quality movement patterns on the FMS may have more utility in predicting MSI than the composite score. OBJECTIVE: To determine if an asymmetry or score of 1 on an individual FMS test would predict MSI in collegiate athletes. DESIGN: Cohort study. SETTING: National Collegiate Athletic Association Division II university athletic program. PATIENTS OR OTHER PARTICIPANTS: A total of 84 Division II rowers, volleyball players, and soccer players (men: n = 20, age = 20.4 ± 1.3 years, height = 1.77 ± 0.04 m, mass = 73.5 ± 4.8 kg; women: n = 64, age = 19.1 ± 1.2 years, height = 1.69 ± 0.09 m, mass = 64.8 ± 9.4 kg). MAIN OUTCOME MEASURE(S): The FMS was administered during preseason preparticipation examinations. Injury-incidence data were tracked for an academic year by each team's certified athletic trainer via computer software. An MSI was defined as physical damage to the body secondary to athletic activity or an event for which the athlete sought medical care, and resulted in modified training or required protective splitting or taping. Composite FMS scores were categorized as low (≤14) or high (>14). Pearson χ(2) analyses were used to determine if MSI could be predicted by the composite FMS score or an asymmetry or score of 1 on an individual FMS test (P < .05). RESULTS: Athletes with FMS scores of ≤14 were not more likely to sustain an injury than those with higher scores (relative risk = 0.68, 95% confidence interval = 0.39, 1.19; P = .15). However, athletes with an asymmetry or individual score of 1 were 2.73 times more likely to sustain an injury than those without (relative risk = 2.73, 95% confidence interval = 1.36, 5.4; P = .001). CONCLUSIONS: Asymmetry or a low FMS individual test score was a better predictor of MSI than the composite FMS score.

Postoperative Rehabilitation After Hip Resurfacing: A Systematic Review.

CONTEXT: Hip-resurfacing arthroplasty (HRA) has become a popular procedure in the treatment of hip-joint arthritis in individuals under the age of 65 y. Although the body of literature examining operative procedures has grown, there is a lack of consistent reporting of the effectiveness of an HRA postoperative rehabilitation program. To date, no systematic reviews have evaluated the available evidence on postoperative rehabilitation programs. OBJECTIVE: To evaluate the available evidence on postoperative rehabilitation programs after HRA. EVIDENCE ACQUISITION: A systematic review was conducted according to the PRISMA guidelines. A search of PubMed, CINAHL, SPORTDiscus, ProQuest, and Google Scholar was conducted in April 2014 using the following keywords alone and in combination: postoperative, postsurgical, rehabilitation, physical therapy, programs, hip resurfacing, arthroplasty, and metal-on-metal. The grading of studies was conducted using the PEDro and Oxford Centre for Evidence-Based Medicine scales. EVIDENCE SYNTHESIS: The authors identified 648 citations, 4 of which met the inclusion criteria. The qualifying studies yielded 1 randomized control trial, 2 case reports, and 1 case series, for a total of 90 patients. Patients were mostly male (n = 86), had a mean age of 48 ± 5.47 y, and had been physically active before HRA. Postoperative rehabilitation programs varied in length (range 8-24 wk) and consisted of at least 3 phases. The methodology to assess program effects varied, but all 4 studies did measure a combination of function, pain, and quality of life using written questionnaires, with follow-up ranging from 9 mo to 1 y. The most common questionnaire was the Harris Hip Score. CONCLUSION: This review found postoperative rehabilitation programs after HRA to be underinvestigated. Limited results indicate that postoperative rehabilitation programs may be effective in improving gait (stride length, velocity, and cadence), hip range of motion, and pain and function, as measured by questionnaires, but not hip strength.

Does core strength training influence running kinetics, lower-extremity stability, and 5000-M performance in runners?

Although strong core muscles are believed to help athletic performance, few scientific studies have been conducted to identify the effectiveness of core strength training (CST) on improving athletic performance. The aim of this study was to determine the effects of 6 weeks of CST on ground reaction forces (GRFs), stability of the lower extremity, and overall running performance in recreational and competitive runners. After a screening process, 28 healthy adults (age, 36.9 +/- 9.4 years; height, 168.4 +/- 9.6 cm; mass, 70.1 +/- 15.3 kg) volunteered and were divided randomly into 2 groups (n = 14 in each group). A test-retest design was used to assess the differences between CST (experimental) and no CST (control) on GRF measures, lower-extremity stability scores, and running performance. The GRF variables were determined by calculating peak impact, active vertical GRFs (vGRFs), and duration of the 2 horizontal GRFs (hGRFs), as measured while running across a force plate. Lower-extremity stability was assessed using the Star Excursion Balance Test. Running performance was determined by 5000-m run time measured on outdoor tracks. Six 2 (pre, post) x 2 (CST, control) mixed-design analyses of variance were used to determine the influence of CST on each dependent variable, p < 0.05. Twenty subjects completed the study (nexp = 12 and ncon = 8). A significant interaction occurred, with the CST group showing faster times in the 5000-m run after 6 weeks. However, CST did not significantly influence GRF variables and lower-leg stability. Core strength training may be an effective training method for improving performance in runners.

The biomechanics of situational baseball: execution and perception of left-handed pitchers' simulated pick-off moves to first base.

The aim of this study was to provide an in-depth analysis of the pick-off play in baseball. Ten collegiate left-handed pitchers and nine base-runners participated in this study. The pitchers were videotaped with four cameras to derive three-dimensional data while performing deliveries in the directions of first base and home plate in a laboratory setting. Deliveries were performed from flat ground. Differences between these deliveries were measured through ten selected joint and segment angles. The base-runners completed two distinct procedures in which they viewed video footage of left-handed pitchers and estimated the intended delivery direction. Base-runners were subsequently interviewed to determine the reasoning behind their decisions. The pitchers' data revealed differences between delivery types in nearly all of the selected angles (P < 0.01). The base-runners' data demonstrated that their ability to discriminate delivery types improved when allowed more viewing time per trial (P < 0.01). Additionally, commonalities exist among the base-runners' focal points on the pitcher while making decisions regarding delivery direction and the kinematic differences between deliveries in left-handed pitchers. The practical significance of these results, however, may be more difficult to interpret.