A bone distraction device having a ratchet and pawl assembly such that incremental rotation is allowed in one direction and prevented in the other, and further having a quick release mechanism such that the ratchet and pawl mechanism can be released to allow free rotation in both directions. The device has a pawl housing mounted onto a rod housing, the pawl housing having a sloping transition shoulder diminishing to transition onto the outer surface of the rod housing. In other embodiments, the device has a sleeve housing with an enlarged end telescopically mounted onto a rod housing, the enlarged end having a sloping transition shoulder diminishing to transition onto the outer surface of the sleeve housing.
