Woolam P J, Lomas B, Stallard J
Orthotic Research and Locomotor Assessment Unit (ORLAU), Robert Jones and Agnes Hunt Orthopaedic and District Hospital NHS Trust, Oswestry, Shropshire, England, UK. PJWoollam@ORLAU
Prosthet Orthot Int. 2001 Apr;25(1):47-52. doi: 10.1080/03093640108726568.
A growing trend in the use of reciprocal walking orthoses for infant paraplegic patients, and their application for control of the lower limbs in very young total body involved cerebral palsy patients, has created a need for smaller components. A prototype design of a hip joint has been produced which provides the following features: adjustable range of flexion/extension control; override on stops to permit sitting; high lateral rigidity; no lateral bearing play; very high rigidity in the sagittal plane; low friction bearings; high resistance to torque about the vertical axis. In addition a size envelope which is more in keeping with the dimensions of infant patients was an important objective. Comparisons were made of the computed structural properties of the prototype joint and existing routinely available standard orthotic hip joints. In each plane of loading the prototype joint had the highest identified structural property. The hinge-bearing material was tested in a representative joint with 200,000 cycles of typical loading. It was also field tested on adult orthoses over a minimum of a 12-month period with the most vigorous of walkers. In neither test did excessive play develop. The mechanical properties of the joint were established using tests advocated in the British Standard on testing lower limb orthosis knee joints. These showed the joint had structurally equivalent performance to a successful reciprocal walking orthosis hip joint, and that the mode of failure was essentially ductile in nature. Production development of the joint is now being undertaken.
在婴儿截瘫患者中使用往复式步行矫形器以及将其应用于极年幼的全身受累脑瘫患者下肢控制的趋势日益增长，这就需要更小的部件。现已制作出一种髋关节原型设计，其具有以下特点：屈伸控制范围可调节；有用于允许坐下的止动装置；侧向刚度高；无侧向轴承间隙；矢状面刚度极高；低摩擦轴承；对垂直轴扭矩的抵抗力强。此外，更符合婴儿患者尺寸的外形尺寸也是一个重要目标。对原型关节和现有的常规标准矫形髋关节的计算结构特性进行了比较。在每个加载平面中，原型关节的结构特性都是最高的。对铰链轴承材料在具有典型加载200,000次循环的代表性关节中进行了测试。还在成人矫形器上进行了至少12个月的现场测试，测试对象是步行最活跃的人群。在这两种测试中均未出现过度间隙。使用英国标准中关于测试下肢矫形器膝关节的测试方法确定了该关节的力学性能。这些测试表明，该关节在结构上与成功的往复式步行矫形器髋关节性能相当，并且失效模式本质上是延性的。目前正在对该关节进行生产开发。
