Correlation analysis of walking function and imaging parameters in patients with adolescent idiopathic scoliosis

English Keywords:Adolescent idiopathic scoliosis  Three-dimensional gait analysis  Imaging

English Abstract:

  【Abstract】 Objectives: To analyze the correlation between walking function and imaging parameters in adolescent idiopathic scoliosis(AIS) patients, in order to provide reference for future assessments and diagnoses using three-dimensional gait analysis. Methods: A total of 33 AIS patients were included, comprising 9 males and 24 females, with an average age of 12.41±2.12 years, an average height of 155.63±11.34cm, an average weight of 43.42±8.71kg, an average Cobb angle of 18.71°±3.42°, and an average lower limb length discrepancy of 0.77±0.53cm. A three-dimensional motion capture system was used to collect gait characteristics of the AIS patients, including spatiotemporal parameters(step length, step speed, step frequency, percentage of support phase time, percentage of double support phase time), kinematic parameters(the range of hip joint flexion and extension, the maximum internal rotation angle of the hip joint, the flexion angle of the hip joint when the foot touches the ground, the range of knee joint flexion and extension, the range of knee joint varus and valgus, the range of ankle joint flexion and extension, the maximum dorsiflexion angle of the ankle joint, the maximum plantar flexion angle of the ankle joint, the range of ankle joint varus and valgus), dynamic parameters(hip joint power, maximum extension moment of the hip joint, maximum external rotation moment of the hip joint, knee joint power, maximum flexion moment of the knee joint, ankle joint power, maximum varus moment of the ankle joint, maximum valgus moment of the ankle joint), and symmetry index. One researcher independently performed three repeated measurements on the full-length lateral X-rays of spine of patients for parameters such as the main curve Cobb angle, thoracic kyphosis angle, lumbar lordosis angle, and pelvic tilt angle. Normality of the data was tested; Pearson correlation analysis was used for normally distributed data, while Spearman correlation analysis was used for non-normally distributed data. Results: The correlation study results indicated that there was no correlation between spatiotemporal parameters and imaging parameters(P＞0.05). The Cobb angle was negatively correlated with the range of internal and external rotation of the convex side ankle joint(r=-0.373). The thoracic kyphosis angle was negatively correlated with the maximum internal rotation angle of the concave side hip joint(r=-0.358) and with the flexion/extension range of motion of both the convex and concave side ankles(r=-0.369/r=-0.394), but positively correlated with the maximum plantar flexion angle of the convex side ankle(r=0.407). The lumbar lordosis angle was positively correlated with the hip flexion angle(r=0.398) when the foot touched the ground on the convex side. The pelvic tilt angle was negatively correlated with the range of internal and external rotation of the convex side ankle joint(r=-0.433), and positively correlated with the maximum dorsiflexion angle of the concave side ankle(r=0.358). The Cobb angle was positively correlated with the maximum inversion moment of the convex and concave ankle joints(r=0.462/r=0.377). The thoracic kyphosis angle was positively correlated with the maximum extension moment of the convex hip joint(r=0.366). The lumbar lordosis angle was positively correlated with the maximum extension moment of the convex hip joint(r=0.393) and negatively correlated with the maximum external rotation moment of the convex hip joint(r=-0.417). The pelvic tilt angle was negatively correlated with the power of the convex hip joint(r=-0.372) and the maximum extension moment of the hip(r=-0.559), and negatively correlated with the power of the concave knee joint(r=-0.388). It was positively correlated with the maximum flexion moment of the concave knee joint(r=0.440). The thoracic kyphosis angle was negatively correlated with the symmetry index(SI) of the ranges of motion for hip flexion and extension(r=-0.405), as well as the SI of knee flexion and extension(r=-0.362); The lumbar lordosis angle was negatively correlated with the SI of hip joint power(r=-0.412); The pelvic tilt angle was positively correlated with the SI of hip flexion and extension range(r=0.691) and step speed(r=0.374). Conclusions: There are strong correlations between radiographic parameters and hip/ankle joint function during walking in patients with mild-to-moderate AIS. These findings suggest that the interaction between the spine and lower limbs should be taken into account in clinical management to achieve more effective corrective outcomes.