Program in Physical Therapy, Washington University in St. Louis School of Medicine, St. Louis, MO, USA.
Program in Physical Therapy, Washington University in St. Louis School of Medicine, St. Louis, MO, USA; Department of Orthopaedic Surgery, Washington University in St. Louis School of Medicine, St. Louis, MO, USA.
Clin Biomech (Bristol). 2021 Apr;84:105335. doi: 10.1016/j.clinbiomech.2021.105335. Epub 2021 Mar 28.
Developmental dysplasia of the hip is characterized by abnormal acetabular and femoral geometries that alter joint loading and increase the risk of hip osteoarthritis. Current understanding of biomechanics in this population remains isolated to the hip and largely focused on level-ground walking, which may not capture the variable loading conditions that contribute to symptoms and intra-articular damage.
Thirty young adult females (15 with dysplasia) underwent gait analysis during level, 10° incline, and 10° decline walking while whole-body kinematics, ground reaction forces, and electromyography (EMG) were recorded. Low back, hip, and knee joint kinematics and internal joint moments were calculated using a 15-segment model and integrated EMG was calculated within the functional phases of gait. Dependent variables (peak joint kinematics, moments, and integrated EMG) were compared across groups with a one-way ANOVA with multiple comparisons controlled for using the Benjamini-Hochberg method (α = 0.05).
During level and incline walking, patients with developmental dysplasia of the hip had significantly lower trunk flexion angles, lumbar and knee extensor moments, and erector spinae activity than controls. Patients with developmental dysplasia of the hip also demonstrated reduced rectus femoris activity during loading of level walking and increased gluteus maximus activity during mid-stance of decline walking.
Patients with developmental dysplasia of the hip adopt compensations both proximal and distal to the hip, which vary depending on the slope of walking. Furthering the understanding of multi-joint biomechanical compensations is important for understanding the mechanism of osteoarthritis development as well as secondary conditions.
发育性髋关节发育不良的特征是髋臼和股骨几何形状异常，改变关节负荷，增加髋关节骨关节炎的风险。目前对该人群生物力学的理解仍然局限于髋关节，并且主要集中在平地行走，这可能无法捕捉到导致症状和关节内损伤的各种负荷情况。
30 名年轻成年女性（15 名患有发育不良）在平地、10°斜坡和 10°下坡行走时进行步态分析，同时记录全身运动学、地面反作用力和肌电图（EMG）。使用 15 节段模型计算低腰、髋关节和膝关节运动学和关节内力矩，并在步态的功能阶段内计算整合的 EMG。使用单向方差分析比较组间的因变量（关节运动学、力矩和整合的 EMG 的峰值），并使用 Benjamini-Hochberg 方法（α=0.05）控制多重比较。
在平地和斜坡行走时，发育性髋关节发育不良患者的躯干前屈角度、腰椎和膝关节伸肌力矩以及竖脊肌活动明显低于对照组。发育性髋关节发育不良患者在平地行走的负重期和下坡行走的中停期，股直肌活动减少，臀大肌活动增加。
发育性髋关节发育不良患者在髋关节的近端和远端都采取了代偿措施，这些代偿措施取决于行走的坡度。进一步了解多关节生物力学代偿对于理解骨关节炎发展的机制以及继发性疾病非常重要。
