The purpose of this study was to assess kinematic lower extremity motion patterns (hip flexion, knee flexion, knee valgus, and ankle dorsiflexion) during various foot-landing techniques (self-preferred, forefoot, and rear foot) between genders. 3-D kinematics were collected on 50 (25 male and 25 female) college-age recreational athletes selected from a sample of convenience. Separate repeated-measures ANOVAs were used to analyze each variable at three time instants (initial contact, peak vertical ground reaction force, and maximum knee flexion angle). There were no significant differences found between genders at the three instants for each variable. At initial contact, the forefoot technique (35.79° ± 11.78°) resulted in significantly (p= .001) less hip flexion than did the self-preferred (41.25° ± 12.89°) and rear foot (43.15° ± 11.77°) techniques. At peak vertical ground reaction force, the rear foot technique (26.77° ± 9.49°) presented significantly lower (p= .001) knee flexion angles as compared with forefoot (58.77° ± 20.00°) and self-preferred (54.21° ± 23.78°) techniques. A significant difference for knee valgus angles (p= .001) was also found between landing techniques at peak vertical ground reaction force. The self-preferred (4.12° ± 7.51°) and forefoot (4.97° ± 7.90°) techniques presented greater knee varus angles as compared with the rear foot technique (0.08° ± 6.52°). The rear foot technique created more ankle dorsiflexion and less knee flexion than did the other techniques. The lack of gender differences can mean that lower extremity injuries (e.g., ACL tears) may not be related solely to gender but may instead be associated with the landing technique used and, consequently, the way each individual absorbs jump-landing energy.

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Educators must transition toward instruction of EBP, regardless of barriers present in their academic programs, in order to maintain progress with other health professions' clinical practices and educational standards. Because today's students are tomorrow's clinicians, we need to include EBP concepts in entry-level education to promote critical thinking, inspire potential research interest, and further develop the available body of knowledge in our growing clinical practice.

The purpose of this study was to assess kinematic and kinetic differences between three tasks (drop-jump, sidestep cutting, and pivot tasks) commonly used to evaluate anterior cruciate ligament risk factors. Nineteen female collegiate soccer athletes from a Division I institution participated in this study. Participants performed a drop-jump task, and two unanticipated tasks, sidestep cutting and pivot. Repeated-measures analyses of variance were conducted to assess differences in the kinematic and kinetic parameters between tasks. The pivot task had lower knee flexion (−41.2 ± 8.8°) and a higher valgus angle (−7.6 ± 10.1°) than the sidestep (−53.9 ± 9.4° and −2.9 ± 10.0°, respectively) at maximum vertical ground reaction force. The pivot task (0.8 ± 0.3 multiples of body weight) had higher peak posterior ground reaction force than the drop-jump (0.3 ± 0.06 multiples of body weight) and sidestep cutting (0.3 ± 0.1 multiples of body weight), as well as higher internal varus moments (0.72 ± 0.3 N · m/kg · m) than the drop-jump (0.14 ± 0.07 N · m/kg · m) and sidestep (0.17 ± 0.5 N · m/kg · m) at peak stance. During the pivot task, the athletes presented a more erect posture and adopted strategies that may place higher loads on the knee joint and increase the strain on the anterior cruciate ligament.

Fatigue has been shown to alter the biomechanics of lower extremity during landing tasks. To date, no study has examined the effects of two types of fatigue on kinetics and kinematics. Objectives This study was conducted to assess biomechanical differences between two fatigue protocols [Slow Linear Oxidative Fatigue Protocol (SLO-FP) and Functional Agility Short-Term Fatigue Protocol (FAST-FP)]. Design Single-group repeated measures design. Methods Fifteen female collegiate soccer players had to perform five successful trials of unanticipated sidestep cutting (SS) pre- and post-fatigue protocols. The SLO-FP consisted of an initial VO2peak test followed by 5-min rest, and a 30-min interval run. The FAST-FP consisted of 4 sets of a functional circuit. Biomechanical measures of the hip and knee were obtained at different instants while performing SS pre- and post-fatigue. Repeated 2 × 2 ANOVAs were conducted to examine task and fatigue differences. Alpha level set a priori at 0.05. Results During the FAST-FP, participants had increased knee internal rotation at initial contact (IC) (12.5 ± 5.9°) when compared to the SLO-FP (7.9 ± 5.4°, p < 0.001). For hip flexion at IC, pre-fatigue had increased angles (36.4 ± 8.4°) compared to post-fatigue (30.4 ± 9.3°, p = 0.003), also greater knee flexion during pre-fatigue (25.6 ± 6.8°) than post-fatigue (22.4 ± 8.4°, p = 0.022). Conclusion The results of this study showed that hip and knee mechanics were substantially altered during both fatigue conditions.

Context: Insufficient lower extremity strength may be a risk factor for lower extremity injuries such as noncontact anterior cruciate ligament tears. Therefore, clinicians need reliable instruments to assess strength deficiencies.Objective: To assess the intrarater, interrater, intrasession, and intersession reliability of a portable fixed dynamometer in measuring the strength of the hip and knee musculature.Design: Crossover study. Setting: Sports medicine research laboratory.Patients or Other Participants: Three raters (A, B, C) participated in this 2-phase study. Raters A and B tested 11 healthy college graduate students (2 men, 9 women) in phase 1. Raters A and C tested 26 healthy college undergraduate students (7 men, 19 women) in phase 2.Main Outcome Measure(s): The dependent variables for the study were hip adductor, hip abductor, hip flexor, hip extensor, hip internal rotator, hip external rotator, knee flexor, and knee extensor peak force.Results: The phase 1 intrasession intraclass correlation coefficients for sessions 1, 2, and 3 ranged from 0.88 to 0. Conclusions: The portable fixed dynamometer showed good to high intrasession and intersession reliability values for hip and knee strength. Intrarater and interrater reliability were fair to high, except for hip internal rotation, which showed poor reliability.

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Although the HPO and ALD produced statistically and clinically decreased VAS scores while walking and jogging, further research is needed beyond these preliminary findings to determine long-term outcomes related to pain relief.