Is there a correlation between isometric muscle strength and the kinematics of the pelvis,hip and knee during functional tasks in women with patellofemoral pain?

ObjectivesTo evaluate the correlation between isometric muscle strength of the hip abductors (HABD) and lateral rotators (HLR) with the range of motion (ROM) of the pelvis/hip in the frontal/transverse planes, respectively, and between the strength of the knee extensors (KExt) with the ROM of the knee in the sagittal plane during seven tasks.DesignCross-sectional study.SettingLaboratory.ParticipantsThirty-five women with patellofemoral pain.Main outcome measuresMaximum isometric muscle strength of the HABD, HLR, and KExt was measured using a manual dynamometer, and pelvis and lower limbs kinematics were evaluated using 3D optical system during gait, ascending and descending stairs, the forward and lateral step down tests, and the propulsion and landing phases of the single leg hop test (SLHT).ResultsA weak correlation was found between KExt strength and knee ROM in the sagittal plane (p = 0.05; r = −0.33) during SLHT landing, and a moderate correlation between HABD strength and ROM of pelvic obliquity (p < 0.01; r = 0.50) during ascending stairs.ConclusionsThe lower strength of KExt has a weak correlation with higher knee flexion during the landing phase of the SLHT, and the lower strength of HABD has a moderate correlation with lower pelvis ROM in the frontal plane when ascending stairs.     

Epidemiology of acute knee injuries seen at the Emergency Department at Umeå University Hospital,Sweden, during 15 years

Purpose

To describe the incidence and injury distribution of knee injuries in the general population of a European setting.

Methods

Retrospective study of all knee injuries registered at the Emergency Department at Umeå University Hospital, Sweden, during 1995–2009 in relation to age, sex, diagnosis, location and activity at the time of injury, mechanism of injury, and treatment and/or follow-up plan.

Results

During 1995–2009, 12,663 knee injuries were registered, 8 % of all injuries. The incidence of knee injuries resulting in a visit to the Emergency Department was six cases per 1,000 person years. One-third of all injuries occurred during sports. And 30 % were 15–24 years. More men than women were injured during sporting activities and women were mostly injured during transportation.

Conclusion

Knee injuries in a general population are common and the injury distribution varies with age and sex. Sports activities and young age were prominent features of the injured population.

Level of evidence

IV.     

Effects of second-generation and indoor sports surfaces on knee joint kinetics and kinematics during 45° and 180° cutting manoeuvres,and exploration using statistical parametric mapping and Bayesian analyses

Sport Sciences for Health - The aim of the current investigation was to examine the influence of second-generation (2G) and indoor surfaces on knee joint kinetics, kinematics, frictional and muscle...     

The effect of the most common gait perturbations on the compensatory limb’s ankle,knee, and hip moments during the first stepping response

BackgroundTrips and slips, the two most common gait perturbations, often cause falls. Multiple studies have focused mainly on the kinematics of multiple body segments in response to an unexpected trip or slip induced by mechanical obstacles, cables, treadmills, and slippery agents or contaminants on a floor. Few studies have examined the joint moments of the compensatory limb following an unexpected trip on an obstacle.Research questionThis proof-of-concept study sought to assess the ankle, knee, and hip moments of the compensatory limb during normal walking and the first stepping response following the two most common gait perturbations.MethodsEighteen healthy young adults completed 4 trials (2 trials with a random trip perturbation and 2 trials with a random slip perturbation) while walking on a split-belt treadmill. In each trial, the motorized treadmill induced either an unexpected trip or slip perturbation to the left foot between the 31 st and 40th step randomly. A motion capture system recorded the positions of body segments, the joint moments (i.e., ankle, knee, and hip moments) of the compensatory limb were quantified, and the maximum joint moments were assessed during normal walking and the first stepping response.ResultsCompensatory limb’s ankle plantarflexion, knee flexion, hip flexion, and hip extension moments were significantly higher for a slip perturbation than for a trip perturbation during the first stepping response. Compensatory limb’s knee flexion, hip flexion, and hip extension moments were also significantly higher during the first stepping response to a slip perturbation compared to normal walking.SignificanceThis proof-of-concept study is the first to investigate the ankle, knee, and hip moments of the compensatory limb during the first stepping response following unexpected gait perturbations induced by a split-belt treadmill. The findings are expected to improve the gait perturbation paradigms developed for training balance-impaired individuals.