Techniques of Yang's arthroscopic discopexy for temporomandibular joint rotational anterior disc displacement

Disc displacement is a common disorder affecting the temporomandibular joint. According to previous publications, the displaced disc can be categorized into pure anterior displacement and rotational displacement (anteromedial and anterolateral). However, the technique of arthroscopy treatment has only been reported for patients with pure anterior disc displacement. In this study, an arthroscopic discopexy for rotational anterior disc displacement was developed and its effectiveness evaluated over 24 months of follow-up. A total of 532 patients (749 joints) with rotational anterior disc displacement, admitted to Shanghai Ninth People's Hospital between January 2011 and December 2015, were included. The success rate was based on clinical parameters (visual analogue scale (VAS) for pain, maximum inter-incisal opening (MIO), and complications) and radiographic data. The clinical and radiographic data were collected preoperatively and at 1, 6, 12, and 24months postoperative. The VAS score decreased to 0.73±1.43 following surgery (P<0.001). A significant improvement in MIO (34.73±6.28mm) was also detected (P<0.001). Magnetic resonance imaging showed discs repositioned in both sagittal and coronal images for 714 of the 749 joints, giving a success rate of 95.3%. This study reports an effective and predictable technique of arthroscopic discopexy for rotational anterior disc displacement.