RESUMO
PURPOSE: To evaluate the posterior septum of the knee and determine the presence of a safe zone that could be removed, without significant damage to blood vessels and nerves. METHODS: Nineteen fresh unpaired adult human cadaveric knees, with no macroscopic degenerative or traumatic changes, were used in this study. Microscopic evaluation was performed by analysis of H&E, CD-34, and S-100 staining. RESULTS: The posterior septum of the knee is rich in type II and type IV mechanoreceptors and blood vessels. The superior half has a greater number of blood vessels (21.52 ± 6.36 v 12.05 ± 4.1, P < .001), higher-caliber vessels (2.2 ± 0.89 µm v 1.41 ± 0.45 µm, P < .006), and a greater number of mechanoreceptors per field (type II, 1.8 ± 1.8 v 0.42 ± 1, P = .04; type IV, 22.6 ± 14 v 14.5 ± 9.4, P = .04) than the inferior half of the septum. CONCLUSIONS: This study has shown that the posterior septum of the knee is highly vascularized and has a great number of type II and IV mechanoreceptors. The presence of these structures is significantly higher in the superior half of the septum. CLINICAL RELEVANCE: If debridement of the posterior septum is necessary, it should be done at the inferior aspect so that a greater number of blood vessels and mechanoreceptors can be preserved.