The Myopathic Gait:

This gait abnormality is sometimes referred to as a waddling gait. The waddle or shift is secondary to proximal pelvic musculature weaknesses.  The client may utilize a limb circumduction strategy to compensate for the weakness in the gluteals or as seen better here displaying an exaggerated alternation of lateral trunk movements with an exaggerated elevation of the hip.  There are some distinct similarities to the Trendelenburg gait pattern.  There are several causes of this gait variant, some of which are temporary and some of which are orthopedic and some neurodegenerative.  For example: pregnancy, hip dysplasia, muscular dystrophy and spinal muscular atrophy.