The dorsal capsulo-scapholunate septum (DCSS) is an anatomic structure linking the scapholunate ligament and the dorsal capsule of the wrist. It should be a predynamic scapholunate stabilizer. The authors, using their experience for the extrinsic ligaments testing, suggest an arthroscopic testing of the DCSS. The status could be graded in 4 stages according to the trampoline aspect and to the fiber attachment. They report a preliminary study on a series of 53 arthroscopies made between January 2014 and December 2015 with evaluation of scapholunate ligament instability and DCSS laxity. There is a significant correlation between the lesional stage of the DCSS and the arthroscopic predynamic scapholunate instability stage (P<0.01).