Parallel external fixator system for correcting single-plane malformation of ankle part

Abstract

The invention relates to a parallel external fixator system for correcting single-plane malformation of an ankle part. The parallel external fixator system comprises a reference ring assembly, a movement ring assembly and a traction rod assembly. In order to meet the correction requirements of different body segments of the ankle part, the reference ring assembly comprises a hexagonal reference ring, a horizontal U-shaped reference ring and a vertical U-shaped reference ring, and the motion ring assembly comprises a large hexagonal motion ring, a small hexagonal motion ring and a U-shaped motion ring. Besides, the traction rod assembly comprise two six-degree-of-freedom traction rods, one three-degree-of-freedom traction rod and two five-degree-of-freedom traction rods, and the specific traction rod assembly is assembled and is connected with the reference ring assembly and the moving ring assembly in parallel, so that switching between a three-degree-of-freedom configuration and a four-degree-of-freedom configuration can be realized. The external fixator system only aims at single-plane ankle deformity, the number of the drivers just meets the deformity correction freedom degree requirement, and the defect that when an existing parallel external fixator corrects the type of deformity, the correction freedom degree is redundant is overcome.

Description

technical field [0001] The invention relates to a parallel external fixator system for feet and ankles, in particular to two parallel mechanisms for assisting the correction of single-plane deformities at the feet and ankles. Background technique [0002] Uniplanar deformity is a simple type of deformity of the foot and ankle, which means that the angular deformity exists in only one plane. In the ankle region, this type of deformity involves: anterior / posterior arch deformity in the sagittal plane of the distal tibia, varus / valgus deformity in the frontal plane of the distal tibia, High arch / equeshoe deformity, high arch / rocker foot deformity in the sagittal plane of the fore-midfoot, pronation / supination deformity in the frontal plane of the fore-midfoot, and adduction / abduction deformity in the transverse plane of the fore-midfoot. When correcting the above-mentioned deformities, in addition to the degree of freedom of rotational correction required for angular deformity...

AI Technical Summary

Problems solved by technology

The correction degrees of freedom required for single-plane deformity are 3 or 4, and the corresponding actuators are also 3 or 4. In clinical applications, the configuration of external fixators based on parallel mechanisms is mostly 6 degrees of freedom. In the process of planar deformity, there is a problem of redundant correction degrees of freedom, which leads to more drives and increases the cost

In the follow-up manual adjustment process for a long period of time, it will increase the difficulty of memory and operation of the patient's family members

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