Myopathic gait
Also known as the waddling gait, the myopathic gait occurs when a person has a weakness in their hip abductors, resulting in a waddling appearance. Hip abductor weakness results in incapability to stabilize the pelvis during stance.
This results in the pelvis tilting downwards towards the unsupported side of the body during the swing phase of the gait cycle.
Causes can include hyperthyroidism, hypothyroidism, Cushing’s syndrome, acromegaly, polymyalgia rheumatic, polymyositis, and dermatomyositis. An individual’s body counteracts to prevent the swinging foot from dragging by:
-Circumducting the leg
-Laterally: Turning the torso away from the leg in the swing phase draws the pelvis and leg up off the floor, causing the “waddling” appearance.
Clinical features that are typically associated with this type of abnormal gait include:
-Positive Trendelenburg’s sign: When a patient stands on one leg, the pelvis falls towards the contralateral side
-Difficulty rising from a seated position without the use of one’s arms
-Struggling to sit up from a lying position or stand from a squat
I am surprised that your list of reasons for gait abnormalities did not include normal pressure hydrocephalus. I started involuntarily shuffling my feet and had diminished stride In my early seventies. When I took Anatomy and Physiology in college, the instructor told us that some people with brain injuries could not stride more than 12 inches when walking. In addition to stride changes, I found it increasingly difficult to organize and reason. I couldn’t put together a report for my work. A CT scan revealed a significantly enlarged third ventricle. I had an ETV performed by image-guided surgery to form a drainage path through scar tissue that blocked the flow of CNS in my third ventricle at OHSU in Portland. I got immediate relief and have no gait or mental confusion symptoms for the last 10 years.