Minimally invasive robotic surgical instruments and related methods are disclosed. A surgical instrument includes an interface fitting that couples a proximal chassis of the instrument with a holding fixture of a robotic manipulator. A securing feature releasably prevents relative axial sliding between the interface fitting and the chassis. In response to binding of the surgical instrument within a minimally invasive surgical site so as to inhibit removal of the surgical instrument from the surgical site and inhibit disengagement of the interface fitting from the holding fixture, the securing feature can be released to allow relative axial sliding between the interface fitting and the chassis, thereby allowing the holding fixture and the interface fitting to be separated from the rest of the surgical instrument and repositioning of the robotic manipulator out of the way.