A surgical spacer comprising first and second hollow support members, a flexible container, and a compressible material disposed in the container is disclosed. The first and second support members each have an exterior and an interior cavity. The exteriors of the first and second support members are affixed together and the interior cavities of the first and second support members are connected via a connecting opening. The container is disposed in the interior cavities and extends through the connecting opening. In addition, the container is substantially impermeable to the compressible material. The first and second support members are more rigid than the flexible container. A combination of the first and second support members controls the shape of the flexible container, with the compressible material disposed therein, in response to a compressive load applied to an exterior of the spacer.