Patients with bilateral CDH walk with the following gait -

Hip girdle muscle is responsible for keeping pelvis level when walking .Weakness on one side will lead to drop in the pelvis on the contralateral side of pelvis while walking(trendelenburg sign ) with bilateral weakness will have dropping of the pelvis on both side during walking leading to waddling. In unilateral CDH- trendelenburg gait antalgic gait us seen in painful condition of lower limb