An inner assembly for a modular surgical drive hub includes a drive adapter, an inner blade adapter, and a compression member, the inner blade adapter mounted within the drive adapter and biased in a distal direction by the compression member, the drive adapter and the inner blade adapter including a key-way and a key for transmitting rotational force from the drive adapter to the inner blade adapter； wherein the inner assembly is configured to be inserted into and retained within the modular surgical drive hub. A modular surgical drive hub and a surgical instrument are described.
