Modified arthroscopic anterior myotomy for internal derangement of the temporomandibular joint: clinical and radiological results.

The aim of this study was to present the results of a modification of the arthroscopic anterior myotomy for the treatment of internal derangement (ID) of the temporomandibular joint (TMJ): the minimally invasive arthroscopic anterior myotomy (MIAAM). Fifteen joints with Wilkes stages III-IV ID treated with this technique were studied. Clinical data evaluated were pain (visual analogue scale, VAS) and articular movements (preoperatively and at 1, 3, 6, 9, and 12 months postoperative). The position of the disc at 1 year after surgery was compared with the pre-surgical position, using magnetic resonance imaging (MRI). The mean pain level according to the VAS decreased from of 67.8 pre-surgery to 29.0 at the 12-month follow-up (P < 0.001). Functionally, mouth opening increased from a mean 27.8 mm to 36.0 mm (P < 0.001). Evaluation of the MRI images showed statistically significant improvements in disc position in both the closed (P = 0.00002) and open-mouth (P = 0.00001) position. The incidence of re-arthroscopy was 13.3% (2/15). This procedure is an effective method for the improvement of joint function and reduction of pain in patients with ID of the TMJ. However, MIAAM is moderately effective in regards to repositioning of the disc.