Success of temporomandibular joint arthroscopy in disk displacement with and without reduction

Forty-three subjects with disk displacement without reduction (DNR) or disk displacement with reduction (DWR) underwent arthroscopic lysis and lavage of the temporomandibular joints. Both groups of subjects were assessed by clinical examination, a questionnaire, and joint imaging, to determine the impact of internal derangement type (DWR vs DNR) on postsurgical outcome. There were no significant differences in postsurgical outcomes between the two groups of meniscal disorders with respect to clinical and questionnaire data. However, the DNR group generally exhibited a smoother, less erratic recovery. After surgery dramatic improvements were in range of motion, pain, and function in both groups, although some level of residual pain and dietary limitation remained in approximately half the subjects. The incidence of joint sounds and deviation were not improved by surgery. Significant differences were found between the two groups with respect to imaging results. Arthroscopy had little effect on the disk positions of DNR subjects: 84% were unchanged after surgery, and the remaining 16% were improved. The disk position of DWR subjects appeared more labile, with 31% unchanged, 38% worsened, and 31% improved.