. More recently, authors have considered low-cost instruments like the inclinometer that may be used in field conditions to assess the JPS in a more clinician-friendly way. 7 , 9 , 10 Previous studies have validated this methodology to assess the JPS in shoulder rotations and knee extension and flexion
Natalia Romero-Franco, Juan Antonio Montaño-Munuera, Juan Carlos Fernández-Domínguez and Pedro Jiménez-Reyes
Gabriel Andrade Paz, Marianna de Freitas Maia, Haroldo Gualter Santana, Humberto Miranda, Vicente Lima and John D. Willson
overuse knee injury, such as anterior cruciate ligament (ACL) rupture and patellofemoral pain. 7 – 9 For example, dynamic knee valgus is the resultant medial collapse of the leg during cutting and landing tasks, resulting in hip adduction and internal rotation, relative medial deviation of the knee and
Jean-Francois Esculier, Laurent J. Bouyer and Jean-Sébastien Roy
Patellofemoral pain (PFP) is one of the most frequent running-related injuries. However, few interventions taking into consideration the specificity of running have been shown to be effective in runners with PFP.
To evaluate the effects of a multimodal rehabilitation program including lower-limb-strengthening/motor-control exercises, advice on running biomechanics, and symptoms management on symptoms, strength, and ground-reaction forces in runners with PFP.
Pre- to post- quasi-experimental.
Gait-analysis laboratory and private physical therapy clinic.
21 runners with PFP (34.1 ± 6.0 y old, symptoms duration 38.1 ± 45.5 mo).
An 8-wk multimodal rehabilitation program including lower-limb- and core-strengthening and motor-control exercises, as well as advice on running gait and symptoms management.
Main Outcome Measures:
The Activities of Daily Living Scale of the Knee Outcome Survey (KOS-ADLS) questionnaire and visual analog scales for usual pain (VAS-U), worst pain (VAS-W), and pain during running (VAS-R) were used to assess changes in symptoms and function. Vertical ground-reaction forces (VGRF) during running and lower-limb isometric strength were also measured.
Statistically and clinically significant improvements (P < .001) were reported on KOS-ADLS (+17.8 pts), VAS-U (−19.2 pts), VAS-W (−28.7 pts), and VAS-R (−32.2 pts) after the intervention. No significant changes in isometric strength were observed. The instantaneous vertical loading rate was decreased after the intervention (P = .002), and this reduction was correlated with changes in KOS-ADLS scores (P = .028).
This multimodal intervention was successful in reducing pain and improving function of runners with PFP. However, no significant changes in lower-limb strength were observed. It appears that changes in VGRF combined with appropriate training advice could explain the clinical outcomes.
Cindy Y. Lin, Liang-Ching Tsai, Joel Press, Yupeng Ren, Sun G. Chung and Li-Qun Zhang
Gluteal-muscle strength has been identified as an important component of injury prevention and rehabilitation in several common knee injuries. However, many conventionally prescribed gluteal-strengthening exercises are not performed during dynamic weight-bearing activities, which is when most injuries occur.
To compare lower-limb muscle-activation patterns between conventional gluteal-strengthening exercises and off-axis elliptical exercises with motorized foot-plate perturbations designed to activate gluteal muscles during dynamic exercise.
Twelve healthy volunteers (26.1 ± 4.7 y) participated in the study. They performed 3 conventional exercises (single-leg squat, forward lunge, and clamshell) and 3 elliptical exercises (regular, while resisting an adduction force, and while resisting an internal-rotation torque). Gluteus medius (GMed) and maximus (GMax), quadriceps, hamstrings, and gastrocnemius muscle activations during each exercise were recorded using surface electromyography (EMG) and normalized to maximal voluntary isometric contraction (MVIC).
Normalized GMed EMG was the highest during the adduction-resistance elliptical exercise (22.4% ± 14.8% MVIC), significantly greater than forward lunge (8.2% ± 3.8% MVIC) and regular elliptical (6.4% ± 2.5% MVIC) and similar to clamshell (19.1% ± 8.8% MVIC) and single-leg squat (18.4% ± 7.9% MVIC). Normalized GMax EMG during adduction-resistance (11.1% ± 7.6% MVIC) and internal-rotation-resistance elliptical (7.4% ± 3.8% MVIC) was significantly greater than regular elliptical (4.4% ± 2.4% MVIC) and was similar to conventional exercises. The single-leg squat required more muscle activation from the quadriceps and gastrocnemius than the elliptical exercises.
Off-axis elliptical exercise while resisting an adduction force or internal-rotation torque activates gluteal muscles dynamically while avoiding excessive quadriceps activation during a functional weight-bearing activity compared with conventional gluteal-strengthening exercises.
Marian E. Kneer
The theory/practice gap in physical education instructional practices has been more or less assumed. Recent research employing data-based analysis has provided some insight about instructional procedures being used. There is little evidence about the existence, size, and reasons contributing to the perceived gap. Instructors N = (128) from 20 randomly selected Illinois secondary schools were interviewed via questionnaire to obtain evidence relative to the perceived gap in the use of instructional “theory.” Results indicate that an overall gap exists in the regular use of planning (40%), teaching approaches (64%), practice (31%), evaluation (40%), and teaching/learning environment procedures (18%). The reason most often given for not using recommended planning, practice, and evaluation procedures was an expressed belief that “it was not necessary” (42%). Recommended instructional practices were used significantly more often by teachers from large schools and by teachers with more inservice education. The amount of instructor teaching experience is significantly related to the use of selected instructional theory.
Rodrigo de M. Baldon, Daniel F.M. Lobato, Leonardo Furlan and Fábio Serrão
The purpose of this study was to compare lower limb kinematics between genders during stair descent. Fifteen females and fifteen males who were healthy and active were included in this study. The lower limb kinematics (pelvis, femur and knee) in the coronal and transversal planes were assessed during stair descent at 30°, 40°, 50° and 60° of knee flexion. The study found that females showed greater knee medial rotation for all the knee flexion angles (P = .02−.001), greater femoral adduction (P = .01 for all variables), with exception for 30° (P = .13), and greater femoral lateral rotation at 60° (P = .04). Females also showed a trend to have greater knee valgus at all the knee flexion angles (P = .06−.11) as well as less contralateral pelvis elevation at 50° and 60° (P = .10 and .12, respectively). This study showed that females carry out the stair descent with a lower limb alignment that might predispose them to develop overuse knee injuries, such as the iliotibial band syndrome and patellofemoral pain syndrome. Further prospective investigations should be carried out to verify whether these variables are factors that could predict these knee injuries.
Gemma V. Espí-López, Pilar Serra-Añó, David Cobo-Pascual, Manuel Zarzoso, Luis Suso-Martí, Ferran Cuenca-Martínez and Marta Inglés
Football is a sport played by many people in the world, but the injury rate is high in both amateur and professional players, and the most common type of injury occurs in the lower limbs. Knee injuries are especially relevant, as they represent 15% of all lower limb injuries in male football
Lori A. Bolgla and Douglas R. Keskula
To provide information on research investigating the relationship between a knee effusion and quadriceps inhibition
Peer-reviewed publications from 1965 to 1997 that investigated the effect of a knee effusion on quadriceps strength.
The studies reviewed involved human subjects. Researchers have used active motion, electromyographic equipment, and isokinetics to measure changes in quadriceps strength after a knee effusion.
Most studies reported that a knee effusion resulted in quadriceps inhibition and inferred that quadriceps inhibition would impair knee function.
The authors believe that additional research is needed to better understand the effect of a knee effusion on knee function. Although a knee effusion might lead to quadriceps inhibition, other factors contribute to normal knee function and might allow enough compensation so that knee function is not affected significantly in the presence of certain effusions.
Liam Anderson, Graeme L. Close, Matt Konopinski, David Rydings, Jordan Milsom, Catherine Hambly, John Roger Speakman, Barry Drust and James P. Morton
sometimes only partly mobile or completely immobile at the knee joint ( Grant, 2013 ). This severely restricts the use of the muscle groups in the lower limbs and results in a period of muscle disuse. Under such circumstances, there is a progressive loss of fat-free mass (FFM; Wall et al., 2013 ), a
Britton W. Brewer, Allen E. Cornelius, Judy L. Van Raalte and Howard Tennen
assess pain, negative mood, knee symptoms and functioning, and adversarial growth. An open response format was used to assess the main rehabilitation goal of participants. Ratings of the average amount of pain that participants experienced on a given day were given on a numerical rating scale (NRS) that