Hsu’s position film is a traditional auxiliary method to diagnose temporomandibular joint disorders, in recent years, with the development of arthrography, arthroscopy, electromyography and other methods of examination, the diagnosis of temporomandibular joint disorders has a more direct and objective standard, this study analyzes the position of the condyle in the Hsu’s position film to explore the diagnostic significance and value of the diagnosis in clinical practice. Materials and methods: 1. Subjects: The cases were selected from the stomatology department of the First People’s Hospital of Hangzhou, from November 2004 to November 2006, the patients with Hsu’s positional radiographs in the TMD patients admitted to the hospital had the information of Hsu’s positional radiographs, and the selection criteria were: A: clinically, there were joint popping, pain, mouth opening limitation, joint strangulation, etc., excluding osteoarthropathies; B: no history of orthodontic treatment, traumatic injury, and treatment history of TMD; C: history of treatment of TMD; D: history of orthodontic treatment, traumatic injury, and treatment of TMD. C: the white line of condylar and fossa bone was clear in the imaging information shown in the Hüsey film, and the joint space was clearly recognizable. 2.1 After the printout of Hirschsprung’s position film, tracing was performed, and the marking points and marking planes were determined on the tracing map. Each joint film was traced three times by the same tracer at different times (one week interval) and then the average value was taken. 2.2 Measurement of marker points The Cohlmia method was used for the measurement of joint space and joint fossa morphology. (1) Take the upper edge of the articular base plate as the horizontal reference line (L1), and make its parallel lines (L2-L4) tangent to the upper edge of the articular fossa at point SF, tangent to the upper edge of the condylar eminence at point SC, and tangent to the top of the articular node at point AE. (2) Make the tangent to the anterior edge of the condylar eminence at point AC, and make the tangent to the posterior edge of the condylar eminence at point PC across the point SF, and make the tangent to the posterior edge of the condylar eminence at point AF across the point AC, and make the tangent to the anterior edge of the articular fossa across PC at point PC at point AF. (3) Make a plumb line of the tangent to the anterior edge of the condyle through AC and intersect it with the anterior edge of the articular fossa at point AF, and make a plumb line of the tangent to the posterior edge of the condyle through PC and intersect it with the posterior edge of the articular fossa at point PF. 2.3 Measurement Items ① Cohlmia method to measure the posterior gap PC-PF (P1) ② Cohlmia method to measure the anterior gap AC-AF (A1) ③ Cohlmia method to measure the superior gap SC-SF (S1) ④ Cohlmia method to measure the height of the articular node L4-L2 (Height) ⑤Angle between the anterior oblique plane of the articular fossa and the horizontal datum line L5-L1 (Angle1) ⑥Angle between the anterior oblique plane of the articular fossa and the tangent line of the posterior oblique plane of the articular fossa L5-L6 (Angle2) ⑦PO1=P1/A1 (Reflecting the sagittal position of the condyle) PO2=S1/Height (reflecting the vertical position of the condyle) ⑨ Angle1 and Angle2 reflect the shape of the joint fossa. Results: Of the 76 cases, 59 cases (77.6%) had unilateral disease and 17 cases (22.4%) had bilateral disease; 30 cases (39.5%) were male and 46 cases (60.5%) were female. The age of the patients ranged from 15 to 55 years old, with a mean of 32.5±10.5 years. Independent samples u-tests on the values of the variables measured by the Cohlmia method were performed sequentially on the right and left joint groups of the patients with TMD, and it was found that there was no significant difference in the position of the left and right condylar processes and the morphology of the articular fossa (P>0.05). DISCUSSION: Many scholars believe that the condyle is not centered when the mandible is in the orthostatic position, especially the condyle is posteriorly deviated is one of the main features of TMJ images in patients with TMD. However, Markovic reported that 86 out of 100 patients with TMJDS showed condylar centrality, and there are also data that condylar non-centrality can be seen in the healthy population. Some previous studies have shown that even in a healthy TMJ population, the condylar position of the TMJ is not the same bilaterally in the same subject, and some scholars have suggested that this discrepancy is related to asymmetry of the skull base structure, asymmetry of the condyles bilaterally, and lateralized mastication. Other scholars have found that the condylar position in the group with healthy TMJs is highly variable and not even significantly different from the group of TMD patients. In the present study, we found that on the ICP of patients with TMD as the standard Hirschsprung’s position film, the sagittal position of the condyle and the morphology of the articular fossa had a great variability, while the vertical position of the condyle had a smaller variability, which indicated that the differences of the joints with the symptoms of TMD in the standard Hirschsprung’s position film were mainly concentrated in the sagittal position of the condyle, whereas there was an individual difference in the morphology of the articular fossa, but it was non-significant when the group as a study subject (P However, the differences were not significant when the group was studied (P > 0.5). The mean value of PO1 for the sagittal position of the condyle was greater than 1, which means that the posterior gap was greater than the anterior gap, which means that the condyle position of patients with TMD was also slightly anterior, which is basically the same as Zhang Zhenkang’s conclusions in his analysis of 100 cases of normal temporomandibular joint X-rays. At the same time, it was found that there was no significant difference between the left and right sides of the condyles in the X-ray films of 76 patients with TMD, either in the sagittal or vertical direction (P＞0.05), and that the standard X-ray film is the image made by X-rays passing through a long and narrow bony slit and crossing the TMJ, which is easily affected by some interfering factors, besides, the individual X-rays are used in the determination of the condylar position. There is a lack of objective criteria for determining the position of the condyle and the changes in the anterior, superior, and posterior spaces of the temporomandibular joint. And even if TMD develops to the stage of osteoarthropathy, some scholars have analyzed the diagnostic value of the standard lateral body layer film of Hsu’s position film through the results of X-ray and naked eye comparison observation of 84 cases of elderly TMJ specimens, and concluded that the ability of X-ray examination is affected by the degree and scope of bone and cartilage pathology, as well as the X-ray method, and has limitations. CONCLUSION: In temporomandibular joint disorders, the change of condylar position in the X-ray film was not obvious and had little diagnostic significance.