A siderail support mechanism comprises a bottom cross-member having a first lower pivot and a second lower pivot, a first support arm and a second support arm. The first support arm includes a first upper pivot shaft and a first lower pivot shaft, the first upper pivot shaft being configured to pivotally attach to the siderail at a first upper pivot and the first lower pivot shaft configured to pivotally attach to the first lower pivot of the bottom cross-member. The first upper pivot includes an oblong slot. The second support arm includes a second upper pivot shaft having a locking cog for locking the siderail in a deployed position. A release handle is centrally positioned on the siderail to enable one-handed operation in disengaging the locking mechanism and lowering the siderail to a stowed position.