DIAGNOSIS AND TRAINING BY IMAGING TECHNOLOGY IN KNEE INJURIES IN BASKETBALL

ABSTRACT Introduction: The research and development of new methods of injury diagnosis and rehabilitation training in benefits to the health and training of athletes is a contemporary priority. Among modern techniques, diagnostic imaging technology stands out. Objective: Study the auxiliary effect of imaging technology in the diagnosis and rehabilitation training of functional knee joint injuries in basketball practice. Methods: 50 basketball players diagnosed and treated in the past four years for knee joint function injuries in a special hospital were selected, including 28 male and 22 female athletes, aged 17 to 25 years. PerkinElmer Spotlight-300 FTIR spectral imaging system was used to scan the articular cartilage sections, visible light and total absorption images of the samples were obtained by reflection mode imaging. Results: The peak infrared feature of the articular cartilage measured by the infrared spectrum imaging technology is very consistent with the FTIR spectrum. After rehabilitation training, the Y test score of female patients increased from 96.72 ± 6.05 to 105.40 ± 4.23, and the Y test score of male patients increased from 98.34 ± 5.33 to 105.51 ± 4.89, showing significant differences. Conclusion: Infrared spectrum imaging technology is an effective technique for identifying functional knee joint injury, and is of great use for diagnosis and training update in basketball players with knee trauma. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.


INTRODUCTION
Due to the strong antagonism of basketball, there will be more frequent application of body collision, jumping, and flying techniques in the process of basketball. 1 For athletes, there is a high probability of sports injury during training and competition.At the same time, because the external factors such as the surrounding field or environment, as well as the internal factors such as the technical level and physical quality of basketball players themselves, may affect the state of basketball players when they play basketball, so the sports injury problem of basketball players occurs very frequently. 2 The problem of lower limb injury, including knee joint function injury, is particularly serious.There are many diagnostic methods for sports injury, for example, the pathological changes of the patient's knee joint can be detected through common imaging methods, including obvious bone spurs, joint space reduction, subchondral bone sclerosis and cysts. 3In addition, through clinical observation, it can be found that the affected knee joint has obvious movement obstruction, the patient's movement ability is reduced, and there is clear bone friction sound during joint movement. 4In this paper, infrared spectrum imaging technology is introduced into the detection of knee joint injury in basketball to evaluate and analyze the risk of injury and the location and cause of injury.To reveal the therapeutic effect of physical therapy after knee joint injury in basketball. 5To provide effective technical support for improving the sports state and life of the athletes, as well as effective recovery training after injury.And the infrared spectrum imaging technology used in this paper is applicable to all kinds of athletes and has a good sense of use experience. 6It can be popularized in a variety of sports scenes to increase the security of athletes.

METHOD Research object information
Through retrospective collection of 50 basketball players diagnosed and treated for knee joint function injury in a special hospital in the past four years, including 28 male athletes and 22 female athletes, aged 17-25 years old, 27 left knee and 23 right knee injuries.The study and all the participants were reviewed and approved by Ethics Committee of Longyan University (NO.LYUST107).The clinical manifestations of the patient are pain and swelling of the knee joint, limited extension and flexion activities, and a certain degree of weight bearing disorder.Physical examination showed that Lachman test was positive, knee joint effusion, etc.Before the experiment, all patients had a certain understanding of the study and signed the informed consent form.

Experimental equipment and principle
The infrared spectral imaging technology total reflection accessory in the form of probe must introduce the infrared light in the Fourier transform infrared spectrometer into the infrared spectral imaging technology probe crystal, and return the infrared light to the spectrometer's light import and export components after the total reflection occurs on the inner surface of the contact between the crystal and the sample.
Optical conduits and optical fibers are common light import and export components.However, due to the limitation of optical conduit, it cannot meet the requirements of this system.
The device adopts mid-infrared hollow optical fiber.The optical fiber is supported by silicon tube and coated with silver and silver iodide from the outside to the inside.The optical bandwidth (800~4000cm-1), optical characteristics and transmission performance are good (the maximum loss of straight line and bending are 2.5dB/m and 3dB respectively), which can minimize optical loss.The acrylate protective layer on the outer layer of the silicon tube has good flexibility and non-toxicity, which can realize in vivo or in vivo detection in the biomedical field.

Image acquisition control
Before image acquisition, it is necessary to select a suitable environment to avoid the influence of external factors.Due to the measured image information of the knee joint, too high will cause sweating, and too low will make the skeletal muscle tremble.The change of body surface temperature will affect the measurement results, so the measurement environment in this paper is indoor, and the temperature is controlled between 25 o C and 27 o C. At the same time, it is also necessary to control the ambient humidity and air dust content to reduce the impact of particles and dust on infrared radiation.Therefore, the test environment is relatively dry and the air quality is good.During the shooting process, the distance between the subject and the equipment is 20cm to ensure that the knee joint is fully measured, which can be manually adjusted according to the actual situation of the subject.Before shooting, the equipment parameters need to be adjusted.Since the human body temperature is generally about 37 o C, the knee joint surface temperature is slightly higher, and the room temperature is between 25 o C and 27 o C, the temperature of the infrared thermal imager is set within the range of 27 o C -38 o C. The emissivity is set at 0.99 standard.
When measuring, the subjects should ensure that their knees are completely exposed, wear loose and light clothes, keep stable in the measuring environment, and take photos and measurements after 10 minutes of adaptation.

Image processing method
The PerkinElmer Spotlight-300 FTIR spectral imaging system was used to scan the sections of healthy and diseased articular cartilage, and the visible light and total absorption images of the samples were obtained through reflection mode imaging.
The content of proteoglycans in the surface and transition areas of articular cartilage is unstable, and the length of the lower surface of cartilage is 200 μ The infrared spectrum used for SVC is organized within the range of m, every 10 μ M is a group of joint spectra.From cartilage 0 to 640 μ The slices of infrared spectrum used for SVR concentration calculation are obtained within the radial depth range of m, every 10 μ M Take a group of joint spectra.Because the edge effect will affect the quality of the slice, one or two spectra of the edge of the surface area will be ignored in the spectral extraction.Table 1 shows the experimental   spectrum number.The SVC and SVR models can be extracted by the Spotlight software of the FTIR spectral imaging system, and constructed and calculated by the Unscrambler X (CAMO Software, Inc., Woodbridge, NJ) multivariate statistical analysis software.

Infrared imaging results of diseased tissue
Figure 1 shows the infrared total absorption image of the cartilage tissue section of the diseased joint in 2 years.Compared with the healthy control, the content of collagen decreased, and the content of proteoglycan in the surface and transition areas also decreased significantly.Because the relative change of the content of the same sample component can be expressed by absorbance.Therefore, with the help of chemometrics algorithms, healthy and diseased articular cartilage tissue can be identified and predicted.

Comparison of FTIRI articular cartilage infrared spectrum effects
Compare the spectrum with the spectrum of articular cartilage obtained by FTIRI. Figure 2 shows the results.The black curve in the figure represents the spectrum obtained using FTIRI, and the vertical coordinate on the right represents its absorbance; The red curve and blue dotted line respectively represent the infrared spectrum at the close position of the articular cartilage measured by the optical fiber ATR measuring device, and the left vertical coordinate is its absorbance.
It can be seen from Figure 2 that the infrared characteristic peaks of articular cartilage measured by infrared spectral imaging technology are in high consistency with FTIRI spectrum.Some characteristic peaks of infrared spectrum imaging technology have shifted slightly, which is because with the change of wavelength, the equivalent penetration depth of attenuation wave is different, resulting in different infrared wavelength absorption of samples.These differences can be ignored.In addition, the difference in spectral absorbance of infrared spectral imaging technology at the adjacent positions shown in the figure is caused by the different contact pressure between the infrared spectral imaging technology crystal probe and articular cartilage tissue.Under different pressure, the contact condition between articular cartilage and the lower cone of infrared spectral imaging technology crystal probe is different, and the spectral absorption intensity will be different.This point can be explored by adding pressure sensing devices.

Measuring effect of glycerol reagent
Glycerin reagent has a single component, standard spectral data is easy to obtain, and can well contact the crystal probe of infrared spectral imaging technology.Therefore, it is very suitable for verifying spectral quality.The device measures glycerol and compares the scanning results with the standard spectrum to verify whether the  mid-infrared hollow fiber ATR coupling probe can be used for the infrared spectrum detection of substances.Figure 3 shows the detection results.The black curve represents the measured spectrum of infrared spectral imaging technology, and the gray curve represents the standard spectrum of glycerol (NITS database).It can be seen that the measured results of glycerol reagent are basically consistent with the results of standard spectrum.

Sample monitoring accuracy
The spectrum of articular cartilage obtained by different preprocessing methods and combination processing, the original and pretreated spectral data are dimensionally reduced by PCA, and the influence of preprocessing methods on spectral characteristics is analyzed on the basis of calculating the scatter diagram of each spectral score matrix.Because of the large difference between the spectra of normal samples and 2-year pathological samples, and the change in the surface area of cartilage matrix is the most obvious.The one-dimensional classification vector of normal articular cartilage and 2-year lesion sample spectrum is

Figure 1 .
Figure 1.Characteristic absorption image of articular cartilage tissue of the lesion (male, 22 years old, left knee joint injury for 2 years).

Figure 2 .
Figure 2. Infrared spectral imaging technology probe measuring device and FTIRI articular cartilage infrared spectral contrast map.

Figure 3 .
Figure 3.Comparison diagram of glycerol spectrum measured by optical fiber infrared spectrum imaging technology probe measuring device and standard glycerol spectrum.((a) Comparison diagram of the two spectra at full band (b) Comparison diagram of the spectra in the elliptical region after amplification)

Table 1 .
Vertical section and infrared spectrum information table of articular cartilage.