Background: Neurocognitive function may be a risk factor for anterior cruciate ligament (ACL) injury by changing neuromuscular control such as muscle activities. However, the effect of differences in neurocognitive function on biomechanics and neuromuscular control related to ACL injury risk is not clear. The purpose of this study was to examine the effect of differences in neurocognitive function on biomechanics and neuromuscular control during an unanticipated side-step cutting motion. Method: The subjects were 15 collegiate female athletes who were divided into two groups using the Symbol Digit Modalities Test (SDMT). The experimental task was an unanticipated side-step cutting motion from a 30 cm high box. We calculated joint angles and moments using a 3-dimensional motion analysis system from the dominant leg, and measured muscle activities using a surface electromyography. We calculated the co-contraction ratio (CCR) as relative muscle activity of the quadriceps to the hamstring. Results: As a result, subjects with a lower SDMT score had significantly increased quadriceps activity before and after ground contact and decreased CCR only after ground contact. Conclusion: In the lower SDMT score group, the quadriceps showed stronger muscle activity than the hamstring during an unanticipated side-step cutting motion. This dominant quadriceps muscle activity has been reported to increase the load on the ACL, and there was a possibility of increasing the risk of the ACL injury. Considering these factors, subjects with lower neurocognitive function could have a high risk of ACL injury due to alterations in muscle activities surrounding the knee.
Objective: To evaluate the association between the cross-sectional area of selected shoulder and scapular muscles and the range of shoulder abduction, early after neck dissection surgery. Patients and Methods: Twenty-seven patients (contributing 34 upper limbs), who had undergone neck dissection surgery for head and neck malignancy, were enrolled into the study. Loss of strength of the trapezius muscle at 1-month post-surgery was quantified by the change in active range of shoulder abduction (%A-ROM), measured by hand-held goniometry in a standing position, from baseline, before surgery. The cross-sectional area of the following muscles were measured on unenhanced computed tomography images after surgery: trapezius, rhomboid, serratus anterior, pectoralis major, deltoid, and biceps brachii. Results: There was a significant positive correlation between the %A-ROM and the cross-sectional area of the rhomboid muscle. Conclusion: Greater active shoulder abduction early after surgery is associated with a greater cross-sectional area of the rhomboid muscle. This muscle should be included in intensive programs for rehabilitation of upper limb movement after neck dissection surgery.
Purpose: The purpose of this study was to investigate urine protein excretion and the effect of muscle strengthening in patients with renal disease. Subjects: Twenty-eight patients (18 to 87 years old) with acute onset renal disease were treated with steroids at the Hospital of Shiga University of Medical Science. Maximum quadriceps force was measured, and 20-minutes sessions in resistance training were started. After 5 weeks, maximum quadriceps force was measured again. Results: Quadriceps force showed no significant difference between before and after intervention. There was negative correlation between mean urinary protein excretion and amount of change in quadriceps force over the 5 weeks (r=-0.40, p=0.038). Conclusions: We observed the patients with reduced urine protein excretion are tends to easier to obtain muscle strengthening. On the other hand, there is a possibility that the patients with increased urine protein excretion are hard to obtain muscle strengthening, during the intervention.