Disclosure of Invention
In order to solve the problems in the prior art, the invention aims to provide a method for acquiring a normal reference value of a joint non-bone modeling partition volume ratio, and the method is characterized in that a knee joint cavity model with bones such as thighbone, hip bone, tibia and the like removed is constructed by adopting a CT (computed tomography) tomography scanning mode for a knee joint; the method comprises the steps of constructing a space rectangular coordinate system by taking a geometric central point of a cavity model as a center, obtaining the volume of the whole cavity by calculating the volume of the cavity in each divinatory bone of the space rectangular coordinate system, and providing accurate data reference for accurately judging the malformation condition of the knee joint, the malformation of the lower limbs and the leg and the injury of the knee joint by analyzing the volume of the cavity of each divinatory bone and the volume ratio of corresponding cavities in each divinatory bone, so that the judgment result is more accurate; and volume data of knee joint cavities of people of all ages with normal leg shapes in each divinatory limit is obtained in a statistical normal distribution mode, and a standard range comparison table of the cavity volumes in each divinatory limit is established, so that the comparison effect is achieved when the foot deformity is judged, and the judgment result is more accurate.
The technical scheme adopted by the invention is as follows:
a method for obtaining a normal reference value of a joint non-bone modeling partition volume ratio comprises the following steps:
s1, constructing a knee joint cavity model;
s2, finding a geometric central point of the knee joint cavity model;
s3, establishing a space rectangular coordinate system by taking the geometric center point of the knee joint cavity model as a coordinate origin;
s4, calculating the volume of the knee joint cavity part in each diagram limit of the space rectangular coordinate system;
and S5, calculating the volume ratio of the knee joint at the outer side and the inner side of the distal femur, the volume ratio of the knee joint at the outer side and the inner side of the tibial plateau, the volume ratio of the knee joint at the front side and the rear side of the distal femur and the volume ratio of the knee joint at the front side and the rear side of the tibial plateau according to the volume of the knee joint cavity part to obtain a normal reference.
Further, before the step S1, the method further includes a step S0. of selecting a demographic sample with normal leg shape and extracting a sample.
Further, the specific step of step S1 is: and carrying out CT tomography three-dimensional reconstruction on the knee joint of each person of the sample to construct a knee joint cavity model.
Further, step S6 is included after step S5, and the obtained data for each volume ratio is normally distributed to obtain a normal reference value for each volume ratio, and a standard range comparison table is constructed.
Further, the number of the volumes of the knee joint cavity parts in the step S4 is 8; the volume of the knee joint cavity part consists of a femur far-end external front side knee joint volume, a femur far-end internal front side knee joint volume, a femur far-end external rear side knee joint volume, a femur far-end internal rear side knee joint volume, a tibia plateau external front side knee joint volume, a tibia plateau internal front side knee joint volume, a tibia plateau external rear side knee joint volume and a tibia plateau internal rear side knee joint volume.
Further, the specific step of step S5 is: each volume ratio is calculated by the following formula:
the volume ratio of the distal femur external medial knee joint to the distal femur lateral knee joint/the distal femur medial knee joint;
the tibial plateau lateral medial knee joint volume ratio is tibial plateau lateral knee joint volume/tibial plateau medial knee joint volume;
the volume ratio of the front knee joint and the rear knee joint at the distal femur is equal to the volume of the front knee joint at the distal femur/the volume of the rear knee joint at the distal femur;
the volume ratio of the tibial plateau anterior-posterior knee joint is tibial plateau anterior knee joint volume/tibial plateau posterior knee joint volume;
the volume of the distal femur lateral knee joint is equal to the volume of the distal femur lateral anterior knee joint plus the volume of the distal femur lateral posterior knee joint;
the volume of the femur far-end medial knee joint is equal to the volume of the femur far-end medial anterior knee joint plus the volume of the femur far-end medial posterior knee joint;
the tibial plateau lateral knee joint volume is the tibial plateau external anterior knee joint volume plus the tibial plateau external posterior knee joint volume;
the volume of the medial tibial plateau knee joint is equal to the volume of the medial tibial plateau anterior knee joint plus the volume of the medial tibial plateau posterior knee joint;
the volume of the distal femur anterior knee joint is equal to the volume of the distal femur external anterior knee joint plus the volume of the distal femur internal anterior knee joint;
the volume of the femoral distal posterior knee joint is equal to the volume of the femoral distal external posterior knee joint plus the volume of the femoral distal internal posterior knee joint;
the tibial plateau anterior knee joint volume is the tibial plateau external anterior knee joint volume plus the tibial plateau internal anterior knee joint volume;
the tibial plateau posterior knee volume is the tibial plateau outer posterior knee volume plus the tibial plateau inner posterior knee volume.
Further, the three-dimensional reconstruction is constructed by using Mimics software.
Further, the sampling of step SO includes the steps of dividing the population into age groups, and randomly sampling the population of each age group.
The invention has the beneficial effects that: the invention relates to a method for acquiring a normal reference value of a joint non-bone modeling partition volume ratio, which comprises the steps of constructing a knee joint cavity model by adopting a CT (computed tomography) tomography scanning mode for a knee joint of a normal person; a space rectangular coordinate system is constructed by taking the geometric central point of the cavity model as the coordinate origin, and the volume of the cavity in each divinatory square of the space rectangular coordinate system and the volume ratio of the corresponding cavity in each divinatory square are analyzed by calculating the volume of the cavity in each divinatory square, so that accurate data reference is provided for accurately judging the abnormal condition of the knee joint, the lower limb and leg abnormality, the injury of the knee joint and the like, and the judgment result is more accurate; and volume data of knee joint cavities of normal people in all age groups in each diagram limit are obtained in a statistical normal distribution mode, and a standard range comparison table of the cavity volumes in all diagram limits is established, so that the comparison effect is achieved when foot deformity is judged, and the judgment result is more accurate. Therefore, the invention has better guiding function for judging the lower limb and leg deformity.
Detailed Description
The invention is further explained below with reference to the drawings and the specific embodiments.
The knee joint cavity model refers to a cavity model used for accommodating non-bone tissues at the knee joint after bones such as thighbone, shinbone and hip bone are removed.
A method for obtaining a normal reference value of a joint non-bone modeling partition volume ratio comprises the following steps:
s1, constructing a knee joint cavity model;
s2, finding a geometric central point of the knee joint cavity model;
s3, establishing a space rectangular coordinate system by taking the geometric center point of the knee joint cavity model as a coordinate origin;
s4, calculating the volume of the knee joint cavity part in each diagram limit of the space rectangular coordinate system;
and S5, calculating the volume ratio of the knee joint at the outer side and the inner side of the distal femur, the volume ratio of the knee joint at the outer side and the inner side of the tibial plateau, the volume ratio of the knee joint at the front side and the rear side of the distal femur and the volume ratio of the knee joint at the front side and the rear side of the tibial plateau according to the volume of the knee joint cavity part to obtain a normal reference.
Further, before the step S1, the method further includes a step S0. of selecting a demographic sample with normal leg shape and extracting a sample.
Further, the specific step of step S1 is: and carrying out CT tomography three-dimensional reconstruction on the knee joint of each person of the sample to construct a knee joint cavity model.
Further, step S6 is included after step S5, and the obtained data for each volume ratio is normally distributed to obtain a normal reference value for each volume ratio, and a standard range comparison table is constructed.
Further, the number of the volumes of the knee joint cavity parts in the step S4 is 8; the volume of the knee joint cavity part consists of a femur far-end external front side knee joint volume, a femur far-end internal front side knee joint volume, a femur far-end external rear side knee joint volume, a femur far-end internal rear side knee joint volume, a tibia plateau external front side knee joint volume, a tibia plateau internal front side knee joint volume, a tibia plateau external rear side knee joint volume and a tibia plateau internal rear side knee joint volume.
Further, the specific step of step S5 is: each volume ratio is calculated by the following formula:
the volume ratio of the distal femur external medial knee joint to the distal femur lateral knee joint/the distal femur medial knee joint;
the tibial plateau lateral medial knee joint volume ratio is tibial plateau lateral knee joint volume/tibial plateau medial knee joint volume;
the volume ratio of the front knee joint and the rear knee joint at the distal femur is equal to the volume of the front knee joint at the distal femur/the volume of the rear knee joint at the distal femur;
the volume ratio of the tibial plateau anterior-posterior knee joint is tibial plateau anterior knee joint volume/tibial plateau posterior knee joint volume;
the volume of the distal femur lateral knee joint is equal to the volume of the distal femur lateral anterior knee joint plus the volume of the distal femur lateral posterior knee joint;
the volume of the femur far-end medial knee joint is equal to the volume of the femur far-end medial anterior knee joint plus the volume of the femur far-end medial posterior knee joint;
the tibial plateau lateral knee joint volume is the tibial plateau external anterior knee joint volume plus the tibial plateau external posterior knee joint volume;
the volume of the medial tibial plateau knee joint is equal to the volume of the medial tibial plateau anterior knee joint plus the volume of the medial tibial plateau posterior knee joint;
the volume of the distal femur anterior knee joint is equal to the volume of the distal femur external anterior knee joint plus the volume of the distal femur internal anterior knee joint;
the volume of the femoral distal posterior knee joint is equal to the volume of the femoral distal external posterior knee joint plus the volume of the femoral distal internal posterior knee joint;
the tibial plateau anterior knee joint volume is the tibial plateau external anterior knee joint volume plus the tibial plateau internal anterior knee joint volume;
the tibial plateau posterior knee volume is the tibial plateau outer posterior knee volume plus the tibial plateau inner posterior knee volume.
Further, the three-dimensional reconstruction is constructed by using Mimics software.
Further, the sampling of step SO includes the steps of dividing the population into age groups, and randomly sampling the population of each age group.
Example 1
A method for obtaining a normal reference value of a joint non-bone modeling partition volume ratio comprises the following steps:
s1, constructing a knee joint cavity model;
s2, finding a geometric central point of the knee joint cavity model;
s3, establishing a space rectangular coordinate system by taking the geometric center point of the knee joint cavity model as a coordinate origin;
s4, calculating the volume of the knee joint cavity part in each diagram limit of the space rectangular coordinate system;
and S5, calculating the volume ratio of the knee joint at the outer side and the inner side of the distal femur, the volume ratio of the knee joint at the outer side and the inner side of the tibial plateau, the volume ratio of the knee joint at the front side and the rear side of the distal femur and the volume ratio of the knee joint at the front side and the rear side of the tibial plateau according to the volume of the knee joint cavity part to obtain a normal reference.
The method for acquiring the normal reference value of the volume ratio of the non-bone modeling partition of the joint ignores the change of the bone-shaped structure, because the change of the bone-shaped structure necessarily causes the change of the shape of the joint; therefore, the present invention realizes the determination of the degree of lower limb-leg deformity by analyzing the joint morphology and volume based on the change in the joint morphology. The joint between the femur and the tibia, including soft tissues such as ligaments and cartilage; changes in joint morphology necessarily affect the structural morphology of, for example, soft tissues in the joint; therefore, the condition of the leg deformity of the lower limb can be judged and analyzed by analyzing the shape of the joint between the femur and the tibia.
The knee joint cavity model of the embodiment can be understood as an equivalent model of a knee joint for connecting a femur and a tibia; the relative position conditions of the femur and the tibia can be reflected by analyzing the morphological change of the knee joint cavity model; thereby providing basis for judging the deformity of the legs of the lower limbs.
After the knee joint cavity model is constructed, the mechanical central point of the knee joint needs to be found in the next step, and the mechanical central point of the knee joint is found as the mechanical central point is superposed with the geometric central point of the knee joint cavity model.
After the geometric central point is found, the embodiment establishes a spatial rectangular coordinate system by taking the geometric central point as the origin of coordinates; the knee joint cavity model is divided into eight parts by the eight diagrams of the space rectangular coordinate system, so that the analysis processing of the knee joint cavity model is facilitated; as the deformity of the legs of the lower limbs often causes the bone abrasion of the knee joint, the gap of the joint is narrowed or the gap of the knee joint is greatly changed due to the bone dislocation, so that the deformity of the bone at the knee joint can be judged by analyzing the volume of the gap of the knee joint. Based on this, the present embodiment calculates the volume of the knee joint cavity portion in each diagram; on the basis, the change of the volume ratio of the two corresponding parts of the knee joint cavity is compared to visually reflect the deformation condition of the knee joint cavity, thereby laying a foundation for judging the knee joint deformity; the volume data of the knee joint cavity part of each divinatory square of the knee joint cavity model of the lower limb normal person is obtained through the method, and the normal reference value of each volume ratio is obtained, so that objective basis is provided for judging knee joint deformity by comparing reference.
Example 2
A method for obtaining a normal reference value of a joint non-bone modeling partition volume ratio comprises the following steps:
s1, constructing a knee joint cavity model;
s2, finding a geometric central point of the knee joint cavity model;
s3, establishing a space rectangular coordinate system by taking the geometric center point of the knee joint cavity model as a coordinate origin;
s4, calculating the volume of the knee joint cavity part in each diagram limit of the space rectangular coordinate system;
and S5, calculating the volume ratio of the knee joint at the outer side and the inner side of the distal femur, the volume ratio of the knee joint at the outer side and the inner side of the tibial plateau, the volume ratio of the knee joint at the front side and the rear side of the distal femur and the volume ratio of the knee joint at the front side and the rear side of the tibial plateau according to the volume of the knee joint cavity part to obtain a normal reference.
Further, before the step S1, the method further includes a step S0. of selecting a demographic sample with normal leg shape and extracting a sample.
Further, the specific step of step S1 is: and carrying out CT tomography three-dimensional reconstruction on the knee joint of each person of the sample to construct a knee joint cavity model.
This example differs from example 1 in that: in order to ensure that the normal reference value has wide applicability, the method is suitable for different individuals; in the embodiment, samples are extracted from normal people in a statistical manner, a large number of cross-sectional images of knee joints of each person in the samples are obtained in a CT tomography manner, three-dimensional reconstruction is performed on the images, a knee joint cavity model is constructed, and analysis processing is performed in the manner of embodiment 1, so that the normal reference value of each volume ratio of each individual in the samples is finally obtained.
The rest is the same as in example 1.
Example 3
This example differs from example 1 in that:
step S6 is further included after step S5, and the obtained data for each volume ratio is normally distributed to obtain a normal reference value for each volume ratio, and a standard range comparison table is constructed.
The sampling of step SO includes the steps of dividing the population into age groups and randomly sampling the population of each age group.
Selecting an area with concentrated numerical values from each volume ratio as a reference value in a normal distribution mode, and providing a data basis for judging lower limb deformity by constructing a standard range comparison table; the normal reference value of the invention is more scientific and reasonable by dividing the crowds of different age groups and randomly sampling in each age group.
The rest is the same as in example 1.
Example 4
This example differs from example 1 in that:
the number of the volumes of the knee joint cavity parts in the step S4 is 8; the volume of the knee joint cavity part consists of a femur far-end external front side knee joint volume, a femur far-end internal front side knee joint volume, a femur far-end external rear side knee joint volume, a femur far-end internal rear side knee joint volume, a tibia plateau external front side knee joint volume, a tibia plateau internal front side knee joint volume, a tibia plateau external rear side knee joint volume and a tibia plateau internal rear side knee joint volume.
Further, the specific step of step S5 is: each volume ratio is calculated by the following formula:
the volume ratio of the distal femur external medial knee joint to the distal femur lateral knee joint/the distal femur medial knee joint;
the tibial plateau lateral medial knee joint volume ratio is tibial plateau lateral knee joint volume/tibial plateau medial knee joint volume;
the volume ratio of the front knee joint and the rear knee joint at the distal femur is equal to the volume of the front knee joint at the distal femur/the volume of the rear knee joint at the distal femur;
the volume ratio of the tibial plateau anterior-posterior knee joint is tibial plateau anterior knee joint volume/tibial plateau posterior knee joint volume;
the volume of the distal femur lateral knee joint is equal to the volume of the distal femur lateral anterior knee joint plus the volume of the distal femur lateral posterior knee joint;
the volume of the femur far-end medial knee joint is equal to the volume of the femur far-end medial anterior knee joint plus the volume of the femur far-end medial posterior knee joint;
the tibial plateau lateral knee joint volume is the tibial plateau external anterior knee joint volume plus the tibial plateau external posterior knee joint volume;
the volume of the medial tibial plateau knee joint is equal to the volume of the medial tibial plateau anterior knee joint plus the volume of the medial tibial plateau posterior knee joint;
the volume of the distal femur anterior knee joint is equal to the volume of the distal femur external anterior knee joint plus the volume of the distal femur internal anterior knee joint;
the volume of the femoral distal posterior knee joint is equal to the volume of the femoral distal external posterior knee joint plus the volume of the femoral distal internal posterior knee joint;
the tibial plateau anterior knee joint volume is the tibial plateau external anterior knee joint volume plus the tibial plateau internal anterior knee joint volume;
the tibial plateau posterior knee volume is the tibial plateau outer posterior knee volume plus the tibial plateau inner posterior knee volume.
Further, the three-dimensional reconstruction is constructed by using Mimics software.
This embodiment is a preferred embodiment of the present invention, and the partition of the knee joint cavity model by the spatial rectangular coordinate system 5 is shown in fig. 1 and 2, that is, the number of the volumes of the knee joint cavity parts is 8; the volume of the knee joint cavity part is composed of a femur far-end inner front side knee joint volume 1, a femur far-end inner back side knee joint volume 2, a femur far-end outer back side knee joint volume 3, a femur far-end outer front side knee joint volume 4, a tibia platform inner back side knee joint volume 6, a tibia platform outer back side knee joint volume 7, a tibia platform inner front side knee joint volume 8 and a tibia platform outer front side knee joint volume 9.
This embodiment gives a formula for specifically calculating each volume ratio in step S5. Some of the data are shown in tables 1 and 2 below, for example.
TABLE 1
|
Numerical value
|
Unit of
|
Distal femoral lateral anterior knee volume
|
4.934
|
cm3 |
Distal femur medial anterior knee volume
|
2.265
|
cm3 |
Distal femoral lateral posterior knee volume
|
6.199
|
cm3 |
Distal femur medial posterior knee joint volume
|
4.144
|
cm3 |
Tibial plateau lateral anterior knee volume
|
4.549
|
cm3 |
Anterior knee joint volume in tibial plateau
|
4.515
|
cm3 |
Lateral posterior knee joint volume outside tibial plateau
|
0.753
|
cm3 |
Posterior knee joint volume in tibial plateau
|
8.376
|
cm3 |
TABLE 2
The rest is the same as in example 1.
The present invention is not limited to the above-described alternative embodiments, and various other forms of products can be obtained by anyone in light of the present invention. The above detailed description should not be taken as limiting the scope of the invention, which is defined in the claims, and which the description is intended to be interpreted accordingly.