[Clinical application of disc reduction and anchorage for diacapitular condylar fracture with disc displacement]

To investigate the effectiveness of disc reduction and anchorage in treatment of diacapitular condylar fracture with disc displacement.

Between June 2019 and June 2021, 20 patients (27 sides) with diacapitular condylar fractures with disc displacement were treated with disc reduction and anchorage combined with internal fixation. There were 15 males and 5 females with a median age of 40 years (range, 8-65 years). The fractures were caused by falling from height in 3 cases, traffic accident in 3 cases, and falling in 14 cases. Among them, there were 13 cases of unilateral fracture and 7 cases of bilateral fractures. Five sides were type A fractures and 22 sides were type B. There were 14 simple diacapitular condylar fractures, 12 diacapitular condylar fractures combined with mandibular chin fractures, and 1 diacapitular condylar fracture combined with mandibular angle fracture. The maximum opening was 5-20 mm (mean, 9.7 mm). The time from injury to operation was 4-20 days, with an average of 11.6 days. The postoperative imaging examination was performed to evaluate the reduction of fracture and disc. The maximum opening at 6 months after operation was recorded, and the clinical dysfunction index (Di) of Helkimo index was used to evaluate the temporomandibular joint function.

All incisions healed by first intention. All 20 patients were followed up 6-10 months (mean, 8 months). Postoperative imaging examination showed that 27 fractures were well reduced, of which 26 were anatomically reduced and 1 was basically reduced; the reduction of the temporomandibular joint disc was excellent in 25 sides, good in 1 side, and poor in 1 side, and the effective rate of disc reduction and anchorage was 96.3%. The occlusion relationship of the patient was stable and basically reached the pre-injury level, the incision scar was hidden, and the mouth opening significantly improved when compared with the preoperative level. The maximum mouth opening was 32-40 mm (mean, 36.8 mm) at 6 months after operation. Maximum opening was more than 35 mm in 17 cases. At last follow-up, joint function reached Di 0 grade in 8 sides, DiⅠ grade in 18 sides, and DiⅡ grade in 1 side. After operation, 2 cases of opening deviation, 1 case of joint click, and 2 cases of temporary disappearance of frontal striae on affected side occurred, which recovered to normal after symptomatic treatment.

For diacapitular condylar fractures with disc displacement, it is necessary to adopt disc reduction and anchorage at the same time of fracture reduction and internal fixation, which can achieve good clinical results.