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CONTEXT: Frontal- and transverse-plane kinematics have been prospectively identified as risk factors for running-related injuries in females. The Running Readiness Scale (RRS) may allow for clinical evaluation of these kinematics. OBJECTIVES: To determine the reliability and validity of the RRS as an assessment of frontal- and transverse-plane running kinematics. DESIGN: Cross-sectional study. SETTING: University research laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 56 novice female runners (median [interquartile range] age = 34 years [26-47 years]). MAIN OUTCOME MEASURE(S): We collected 3-dimensional kinematics during running and RRS tasks: hopping, plank, step-ups, single-legged squats, and wall sit. Five clinicians assessed RRS performances 3 times each. Interrater and intrarater reliabilities of the total RRS score and individual tasks were calculated using the intraclass correlation coefficient and Fleiss κ, respectively. Pearson product moment correlation coefficients between peak joint angles measured during running and the same angles measured during RRS tasks were computed. Peak joint angles of high- and low-scoring participants were compared. RESULTS: Interrater and intrarater reliabilities of assessment of the total RRS scores were good (intraclass correlation coefficients = 0.75 and 0.80, respectively). Reliability of assessing individual tasks was moderate to almost perfect (κ = 0.58-1.00). Peak hip adduction, contralateral pelvic drop, and knee abduction during running were correlated with the same angles measured during hopping, step-ups, and single-legged squats (r = 0.537-0.939). Peak knee internal rotation during running was correlated with peak knee internal rotation during step-ups (r = 0.831). Runners who scored high on the RRS demonstrated less knee abduction during running (P ≤ .01). CONCLUSIONS: The RRS may effectively assess knee abduction in novice runners, but evaluation criteria or tasks may need to be modified to effectively characterize pelvic and transverse-plane knee kinematics.

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CONTEXT: Quadriceps dysfunction is a common consequence of knee joint injury and disease, yet its causes remain elusive. OBJECTIVE: To determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion affect the magnitude of quadriceps dysfunction. DESIGN: Crossover study. SETTING: University research laboratory. PATIENTS OR OTHER PARTICIPANTS: Fourteen (8 men, 6 women; age = 23.6 ± 4.8 years, height = 170.3 ± 9.16 cm, mass = 72.9 ± 11.84 kg) healthy volunteers. INTERVENTION(S): All participants were tested under 4 randomized conditions: normal knee, effused knee, painful knee, and effused and painful knee. MAIN OUTCOME MEASURE(S): Quadriceps strength (Nm/kg) and activation (central activation ratio) were assessed after each condition was induced. RESULTS: Quadriceps strength and activation were highest under the normal knee condition and differed from the 3 experimental knee conditions (P < .05). No differences were noted among the 3 experimental knee conditions for either variable (P > .05). CONCLUSIONS: Both pain and effusion led to quadriceps dysfunction, but the interaction of the 2 stimuli did not increase the magnitude of the strength or activation deficits. Therefore, pain and effusion can be considered equally potent in eliciting quadriceps inhibition. Given that pain and effusion accompany numerous knee conditions, the prevalence of quadriceps dysfunction is likely high.

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The objective of this study was to assess the impact of combined transection of the anterior cruciate and medial collateral ligaments on the intact and healing ligaments in the ovine stifle joint. In vivo 3D stifle joint kinematics were measured in eight sheep during treadmill walking (accuracy: 0.4+/-0.4mm, 0.4+/-0.4 degrees ). Kinematics were measured with the joint intact and at 2, 4, 8, 12, 16 and 20 weeks after either surgical ligament transection (n=5) or sham surgery without transection (n=3). After sacrifice at 20 weeks, the 3D subject-specific bone and ligament geometry were digitized, and the 3D distances between insertions (DBI) of ligaments during the dynamic in vivo motion were calculated. Anterior cruciate ligament/medial collateral ligament (ACL/MCL) transection resulted in changes in the DBI of not only the transected ACL, but also the intact lateral collateral ligament (LCL) and posterior cruciate ligament (PCL), while the DBI of the transected MCL was not significantly changed. Increases in the maximal ACL DBI (2 week: +4.2mm, 20 week: +5.7mm) caused increases in the range of ACL DBI (2 week: 3.6mm, 20 week: +3.8mm) and the ACL apparent strain (2 week: +18.9%, 20 week: +24.0%). Decreases in the minimal PCL DBI (2 week: -3.2mm, 20 week: -4.3mm) resulted in increases in the range of PCL DBI (2 week: +2.7mm, 20 week: +3.2mm). Decreases in the maximal LCL DBI (2 week: -1.0mm, 20 week: -2.0mm) caused decreased LCL apparent strain (2 week: -3.4%, 20 week: -6.9%). Changes in the mechanical environment of these ligaments may play a significant role in the biological changes observed in these ligaments.

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Nutrition, in sufficient amount and substance, is crucial for healthy growth and development of the skeleton and surrounding tissues, especially in physically active populations. Inadequate nutrition has been linked to maladies such as the female athlete triad, as well as poor training or competitive performance and increased risk of injury. Dietary choices favoring items high in quality protein of animal or plant origin, polyunsaturated fatty acids, fruits and vegetables high in potassium and fiber, and dairy products or other beverages fortified with calcium and vitamin D are essential to athletes to ensure adequate vitamin and mineral availability to the skeleton, which in turn can affect peak physical performance.

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Mechanical loading is a crucial factor for maintaining skeletal health. Physical activities, exercise, and sports provide a wealth and variety of mechanical loads to bones, through muscle forces, ground reaction forces, and other contact or impact forces. Weightbearing activities can be effective exercises to enhance bone health-particularly, those that involve jumping and impact loads (with greater strain magnitudes, rates, and frequencies). Physical activity appears to be acutely beneficial for enhancing bone health in the early pubertal period and in older age, such as in postmenopausal women. In preparing this article, PubMed, Web of Science, and relevant edited books (English language) were reviewed from 1961 to present.

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The objective of this study was to use an ovine stifle joint model to assess the impact of combined transection of the anterior cruciate and medial collateral ligaments on three-dimensional (3D) joint motion serially over 20 weeks after transection. In vivo 3D kinematics were measured in the right hind limb of eight sheep while walking on a treadmill (accuracy, 0.4 mm +/- 0.4 mm, 0.4 degrees +/- 0.4 degrees ). Five sheep received surgical ligament transection and three sheep received sham surgery without transection. At 2 weeks after transection, average joint flexion at hoof strike was significantly increased (8.9 degrees +/- 3.0 degrees ), and the tibial position was significantly shifted in the anterior direction relative to the femur during midstance (4.9 mm +/- 0.9 mm). By 20 weeks after transection, joint flexion had normalized, but the tibial position was significantly adducted (0.5 degrees +/- 0.7 degrees ) and shifted in the medial (2.5 mm +/- 1.2 mm), anterior (5.8 mm +/- 1.9 mm), and superior directions (1.6 mm +/- 0.4 mm). At 2 and 20 weeks after surgical intervention, the maximal anterior tibial position was significantly increased during mid-stance in the transected group (4.9 mm +/- 0. 9 mm and 5.8 mm +/- 1.9 mm) compared to the sham operated group (0.2 mm +/- 0.2 mm and -0.1 +/- 0.1 mm). Although the anterior tibial shift was observed in all transected sheep, a high degree of variability existed between sheep, in the initial joint position, the magnitude of the early change, the change over time, and the change at 20 weeks. In this situation statistics must be interpreted carefully, and in future studies, individual changes should be assessed in the context of individual pathological changes in order to investigate potential clinical significance.

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INTRODUCTION: Spinal mobilization is commonly used in the treatment of patients with back pain, including individuals with osteoporosis. Previous data indicated that traditional predictors of skeletal failure-lateral or anteroposterior bone mineral density (BMD) by dual energy X-ray absorptiometry (DXA) or geometry of the spinous process or vertebral body-do not predict failure load during posteroanterior spinal mobilization. Morphological differences and inhomogeneities in BMD may have important effects on vertebral strength but integral BMD values by DXA cannot reflect these potentially important differences. We investigated the determinants of spinal fracture using muCT. MATERIALS AND METHODS: We measured failure load and failure site in 11 T5-8 cadaveric specimens (mean age 78 years) when a posteroanterior load was applied at the spinous process of T6 using a servohydraulic material testing machine. Radiography and CT scan were used to verify failure site. We observed no damage to the adjacent T7 vertebrae following the T6 posteroanterior failure test. The T7 vertebrae were sectioned to produce regional samples of the spinous process, the lamina and a vertebral body core. Each sample was scanned with muCT to measure bone microarchitectural parameters. We segmented and analysed four trabecular regions (spinous process base and middle, central lamina and central vertebral body). We used one-way repeated measures ANOVA to compare regions and computed Pearson correlations to assess the relation between PA failure load of T6 and the morphological parameters of T7. RESULTS: The BV/TV at the base or middle of the T7 spinous process (fracture sites), Tb.N and Tb.Th at the base were significantly correlated with posteroanterior failure load of T6 (BV/TV base: r=0.74, p=0.01; BV/TV middle: r=0.73, p=0.01; Tb.N base: r=0.64, p=0.03; Tb.Th base: r=0.65, p=0.03). The Tb.Th of the lamina was significantly greater than Tb.Th of the spinous process base (p=0.002). CONCLUSIONS: Whereas previous data indicated that BMD by DXA was not a good predictor of posteroanterior failure load, regional BV/TV of the spinous process base and middle regions, the sites of fracture, are correlated with posteroanterior failure load. Trabecular thickness differed significantly between the base of the spinous process and the lamina, and may have influenced the site of fracture.

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A robust accountability strategy is at the core of creating a safe, efficient, effective and sustainable system of healthcare. The commitment to be accountable must extend far beyond the providers of care to include every person involved in the funding, administration, delivery and support of patient care (both directly and indirectly). The Alberta Bone and Joint Health Institute has fostered a new system that will measure, analyze and give valuable feedback to all stakeholders in all three essential domains of system accountability: access, quality and cost. The Institute has employed four key strategies to create system accountability in a hip and knee pilot project: collaboration between stakeholders in defining goals and measures that matter to them; the use of "world's best evidence" to drive decisions and to establish goals and benchmarks to measure against; collection of useful data and its analysis to inform improvement decisions; and timely feedback of relevant data in domains of interest to stakeholders on system outputs in the key domains. While these strategies have not yet been proven to be effective in creating the desired "culture of accountability," they are having a significant clinical impact and do have potential to lead to that outcome.

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