RESUMEN
OBJECTIVES: Although the rotation of lower extremities has gained increasing recognition as a risk factor for anterior cruciate ligament (ACL) injury. This study clarified the influence of lower extremity rotation on the knee during single-leg landing. DESIGN AND SETTING: We recruited 30 students to perform single-leg landing from a height of 30 cm with their lower extremities in neutral, and externally and internally rotated. The knee abduction, flexion angles, and abduction angular velocity were measured. Furthermore, the abduction angle was analyzed at knee flexion angles of 15°, 20°, 25°, and 30° and compared among the three conditions using a repeated measures analysis of variance with Bonferroni post hoc tests. RESULTS: The maximum abduction angle was significantly greater when internally rotated than in the neutral. The maximum abduction angular velocity was significantly greater in the internally rotated compared to in the neutral. Finally, the abduction angle at a knee flexion angle of 30° was significantly greater when internally rotated compared to in the neutral. CONCLUSION: Rotation of the lower extremities affects knee kinematics, and landing on a knee that is internally rotated may increase the risk of ACL injury.
Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Pierna , Humanos , Fenómenos Biomecánicos , Rotación , Articulación de la Rodilla , Extremidad InferiorRESUMEN
BACKGROUND: To clarify the changes in the echo intensity (EI) in the prefemoral fat pad (PFP) and identify the relationship between the PFP and clinical features of knee osteoarthritis (OA). METHODS: Twenty-six women with knee OA (mean age: 76 years) and 17 healthy women (mean age: 73 years) were enrolled. The Kellgren and Lawrence grading scale was used for the radiographic evaluation of knee OA. The EI of the PFP was measured as grayscale values. The change ratio of the anteroposterior PFP length during quadriceps contraction was measured. Knee range of motion and pain (100-mm visual analog scale) were evaluated. RESULTS: The EI was significantly higher in the OA group than in the healthy group (P < 0.001). The change ratio of the PFP in the OA group was significantly lower than that in the healthy group (P < 0.001). The ranges of knee flexion and extension were correlated with the EI of the PFP (both P < 0.01) and the change ratio of the PFP (both P < 0.01). There was no significant correlation observed with knee pain. CONCLUSION: Hyperechoic changes and a decreased change ratio of the PFP were observed in the patients with knee OA. High EI and decreased morphological PFP changes were associated with decreased ranges of motion.
RESUMEN
BACKGROUND: The present study aimed to elucidate the effects of heel lifts on spinal alignment, walking, and foot pressure pattern in elderly individuals with spinal kyphosis. METHODS: The spinal alignment, walking speed, step length and foot pressure of 33 community-dwelling elderly individuals with spinal kyphosis (3 men, 30 women; mean age 77.3 years) were examined before and after the application of 10-mm moderately elastic heel lifts. FINDINGS: Spinal alignment of total inclination (mean value 6.9°vs 4.5°) and thoracic angle (43.6°vs 36.2°) were significantly lower after the application of heel lifts than before the application. The lumbar angle (7.3°vs 10.0°) was significantly higher after the application than before the application. Walking speed (0.78 vs 0.88 m/s) and step length (0.42 m vs 0.45 m) were significantly higher after the application. The partial foot pressure as a percentage of body weight of the hallux (6.7% vs 9.0%) and lateral toes (6.5% vs 9.0%) was significantly higher after the application of heel lifts than before the application. The partial foot pressure as a percentage of body weight of the heel (68.9% vs 57.5%) was significantly lower after the application than before the application. INTERPRETATION: In conclusion, heel lifts influenced the sagittal spinal alignment of elderly individuals. Walking speed and step length increased after the application of these devices. Increase in foot pressure in the hallux and lateral toe areas was probably related to these improvements in walking parameters.