STUDY DESIGN: Comparative cross-sectional study. PURPOSE: We measured the vertical ground reaction force (vGRF) of the hip, knee, and ankle joints during normal gait in normal patients, adolescent idiopathic scoliosis (AIS) patients with a Cobb angle < 40° and in AIS patients with spinal fusion. We aimed to investigate whether vGRF in the aforementioned joints is altered in these three groups of patients. OVERVIEW OF LITERATURE: vGRF of the lower limb joints may be altered in these groups of patients. Although it is known that excessive force in the joints may induce early arthritis, there is limited relevant information in the literatures. METHODS: We measured vGRF of the hip, knee, and ankle joints during heel strike, early stance, mid stance, and toe-off phases in normal subjects (group 1, n=14), AIS patients with Cobb angle < 40° (group 2, n=14), and AIS patients with spinal fusion (group 3, n=13) using a gait analysis platform. Fifteen auto-reflective tracking markers were attached to standard anatomical landmarks in both the lower limbs. The captured motion images were used to define the orientations of the body segments and force exerted on the force plate using computer software. Statistical analysis was performed using independent t-test and analysis of variance to examine differences between the right and left sides as well as those among the different subject groups. RESULTS: The measurements during the four gait phases in all the groups did not show any significant difference (p>0.05). In addition, no significant difference was found in the vGRF measurements of all the joints among the three groups (p>0.05). CONCLUSIONS: A Cobb angle < 40° and spinal fusion did not significantly create imbalance or alter vGRF of the lower limb joints in AIS patients.
Adolescent ; Ankle Joint ; Ankle ; Arthritis ; Cross-Sectional Studies ; Gait ; Heel ; Hip ; Humans ; Joints ; Knee ; Lower Extremity ; Scoliosis ; Spinal Fusion ; Strikes, Employee

Introduction: In this study, we evaluated the kinematics of lower limb during early and late phases of 2km time trial on stationary rowing ergometer among Malaysian male rowers. Methods: Seventeen national-level rowers voluntarily participated. Three dimensional lower limb kinematics data were collected to represent the first 400 m (i.e., early) and the last 400m (i.e., late) phases of 2km time trial on a stationary ergometer. The kinematics data at sagittal, frontal and transverse planes of dominant leg during catch and finish positions were compared across early and late phases of the time trial using paired T-test. Results: The kinematics of lower limb joints at three planes were not significantly different during early versus late phases of 2km time trial among male senior rowers except for hip flexion at finish (p=0.411), ankle rotation at catch (p=0.779) and ankle abduction at finish (p=0.677). Conclusion: Lower limb kinematics particularly the hip flexion, ankle rotation and ankle abduction may change across early and late phases of 2km time trial due to fatigue. Coaches and rowers should monitor these motions during fatiguing rowing piece and develop necessary injury prevention measures.

Background: Strength of leg musculature is crucial to generate propulsive force during rowing. The purpose of this study was to determine the relationship of isokinetic dominant leg strength and 2 km time trial on stationary rowing ergometer among male national rowers. Methods: Seventeen male national rowers were recruited for the study. Their hip and knee isokinetic strength were determined in the sagittal plane at 60°/s angular velocity. The relationship between the hip and knee strength, and 2 km time trial performance were evaluated using Pearson correlation. Results: The national rowers completed the 2 km time trial duration in 7.20±0.39 minutes. The hamstring to quadriceps ratio (H:Q) was significantly correlated to 2 km time trial performance (r=-0.491, p=0.045). No other significant relationships between hip and knee isokinetic strength and 2 km time trial performance were observed. Conclusion Increased isokinetic knee strength ratio (H:Q) may enhance 2 km time trial performance among male national rowers. Other isokinetic variables of hip and knee isokinetic strength were not significantly related to 2 km time trial.
Hip ; Knee ; Muscle Strength ; Athletic Performance

Introduction: Introduction: Knee valgus which also known as dynamic knee valgus (DKV), is frequently linked to non-contact lower-limb injuries, especially in females. This retrospective study aims to compare the kinematic variables of lower limb joints in physically active females with normal versus excessive DKV during single leg squat (SLS) at 45° and 60° knee flexion. Methods: Based on the outcomes of drop vertical jump screening test, 34 females were recruited and divided into two groups (i.e., normal and excessive DKV). Participants performed SLS at 45° and 60° knee flexion with three-dimensional motion capture and analysis. The kinematic variables of lower limb joints at both knee flexion of SLS were compared across groups using independent T-test. Results: During 45° SLS with the dominant limb, the normal DKV group performed significantly greater hip adduction angle (4.49±3.25°, t(32) = 2.371, p= 0.024) than the excessive DKV group (1.426±4.23°). During 60° SLS with the dominant limb, the normal DKV group showed knee adduction (0.223±0.07°, t(16.048) = 10.707, p=0.001) while the excessive DKV group showed knee abduction (-4.478±1.81°). Conclusion: Females with excessive DKV showed significantly different lower limb kinematics and motion control strategy compared to females with normal range of DKV. The findings highlighted the importance of DKV screening among physically active females, and the rationale for prescribing individualized exercise intervention to prevent lower limb non-contact injuries.