Objective To evaluate the survival condition and quantitative variation of mechanoreceptors in the tibial remnant of ruptured anterior cruciate l igament (ACL) in human knees. Methods Between April 2009 and May 2010, 60 patients who underwent arthroscopic ACL reconstruction were included and divided into 4 groups according to the time of injury, with 15 patients in each group. In group A, there were 14 males and 1 female aged 20-37 years (mean, 27 years); the injury was caused by traffic accident in 5 cases and by sports in 10 cases, and the time between injury and surgery was not more than 3 months. In group B, there were 14 males and 1 female aged 17-43 years (mean, 24 years); the injury was caused by traffic accident in 2 cases and by sports in 13 cases; and the time between injury and surgery was 3 to 6 months. In group C, there were 11 males and 4 females aged 16-53 years (mean, 28 years); the injury was caused by traffic accident in 2 cases and by sports in 13 cases; and the time between injury and surgery was 6 to 12 months. In group D, there were 12 males and 3 females aged 18-41 years (mean, 26 years); the injury was caused by sports in 11 cases, and the other 4 cases had no defined etiology; and the time between injury and surgery was more than 12 months. Specimens were donated by the volunteers from the anteromedial side of the ACL tibial remnant (40 sl ices per specimen) and stained via immunohistochemical method. The type, size, and quantity of mechanoreceptors were observed under l ight microscope. Results Totally 80 Ruffini-l ike corpuscles, 8 Pacini-l ike corpuscles, 5 atypical neural endings and no distinct Golgi organ-l ike corpuscles were observed under l ight microscope in 60 specimens (2 400 sl ices) of 4 groups. There was no obvious difference in size and type of mechanoreceptors among 4 groups. However,
some degenerative and atrophic changes could be observed in the specimens of group D. The total number of echanoreceptors was 31 (35.2%) in group A, 22 (25.0%) in group B, 23 (26.1%) in group C, and 12 (13.7%) in group D. There was no significant difference (P  gt; 0.05) in Ruffini-l ike corpuscles and Pacini-l ike corpuscles among 4 groups. Mechanoreceptors were found in 9,8, 9, and 6 patients in groups A, B, C, and D, respectively; the detection rates were 60.0%, 53.3%, 60.0%, and 40.0%, respectively; showing no significant difference (P  gt; 0.05). Conclusion The mechanoreceptors in tibial residual of ruptured ACL have a long survival without obvious degeneration and atrophy within 12 months. So it may contribute to restoration of proprioceptive function after operation if the remnant is preserved during ACL reconstruction.

Citation： SHA Lin,ZHAO Jinzhong.. QUANTITATIVE STUDY ON MECHANORECEPTORS IN TIBIAL REMNANTS OF RUPTURED ANTERIOR CRUCIATE LIGAMENT IN HUMAN KNEES. Chinese Journal of Reparative and Reconstructive Surgery, 2010, 24(11): 1318-1322. doi: Copy