While most of us take walking for granted, bipedal movement is a highly complex and sophisticated skill. It is a skill that humans developed parallel with the development of higher cortical structures and capabilities, so it should be no surprise that gait abnormalities can be caused by a wide range of diseases. Fortunately, most of these diseases can be recognized by careful observation during the examination and by using standardized gait testing.
The most important classification of gait patterns is based on the sagittal plane kinematics of the legs during the swing phase of the gait cycle (Figure 11.1). During normal gait, the foot begins to contact the ground with a heel strike, the leg moves forward into mid-stance, and then into terminal stance. The foot then rises into toe-off, and the cycle repeats.
Hemiplegic gait is characterized by weakness on one side of the body and spasticity in the lower extremities. Typically, this results in short steps, a shuffled gait, and difficulty starting or stopping walking. This type of gait pattern can be due to a number of diseases including stroke, cerebral palsy, spinal cord injury, and multiple sclerosis.
Another classification of gait patterns is based on their response to specific gait and balance tests. For example, patients with a cerebellar lesion will typically demonstrate ataxia when asked to walk backwards, whereas patients with functional ataxia that has an organic origin can perform gait and balance tests (such as walking with a partner or stepping in place) with no apparent incongruencies or anomalies.
Physiotherapists often use an examination method known as the Trendelenburg test to help diagnose weakness in a patient’s hip girdle muscles. This is a simple test that involves standing the patient with their feet together, then asking them to lift one leg into the air. If the therapist sees that the leg that is being lifted is significantly lower than the other, they will know that the patient has a trendelenburg gait.
Many other gait abnormalities can be seen during a physical exam and by using specialized tests. For example, a patient with foot drop will have a “steppage gait” during their walking that can make the toes of the opposite foot scrape the ground and may appear a bit slap stick when walking. This is usually due to weak muscles in the hip girdle on one side of the pelvis.
Similarly, patients with lumbar spine or musculoskeletal injuries that impact the knee and ankle joints can be identified by a clunking or shuffling gait pattern that is aggravated by bending or squatting. These types of gait abnormalities are sometimes interpreted as dystonic by clinicians who are not familiar with the clinical presentation and progression of these disorders, but they can be reevaluated by assessing for inconsistencies and anomalies with the use of other standardized balance and gait testing. For instance, improvements with walking backwards or stepping in place suggest that these symptoms are not functional but rather have an organic origin and may be a manifestation of dystonia.