In part one, we defined cadence and gait speed and how they impact falls. While these two variables have a high impact on fall risk, there are other variables that can be assessed and adjusted to decrease fall risk. Step length can be especially telling when it comes to fall risk in older adults.
Step length is a contributing factor to gait speed. Typically, shorter step lengths are associated with decreased gait speed, and as learned in Part 1, decreased gait speed can lead to higher mortality rates.
So, it would seem natural that all fall risk patients should strive to increase the step length using verbal cues and other gait strategies, but that’s not always the case. D.D. Espy et. al. (2010) conducted a study on the impact of separating step length and gait speed. They concluded that step length shrinks as individuals become less confident with gait safety. Decreased step length, independent of speed, allows individuals to catch themselves more quickly when a slip occurs. The researchers concluded that most people lower their step length in reaction to their fear of falling.
People of all ages use this same strategy. When walking on ice or another slippery surface, we naturally shorten our step length to keep our center of mass closer to our base of support. This is a natural fall risk strategy. Unfortunately, for the aging population, it becomes an adaptive behavior due to long-standing confidence issues with falling or loss of balance.
For these patients, a more robust treatment must be considered. Using the mCTSIB assessment could be a way to determine which balance system the patient is relying on. Strength deficits specific to proximal hip strength should be assessed. Once their strengths and weakness are identified, therapists can work on the individuals' deficiencies and improve their overall confidence. After confidence is improved, verbal cues and step length strategies can be initiated.
Step Length Variability
Step length can be a valuable data point for fall risk as well. Usually categorized as symmetrical or asymmetrical, step length variability is when steps are considerably different from step to step and without a regular rhythm. This study concluded that a person with decreased step length results in decreased foot clearance. Increased variability in step length contributes to an increase in falls, secondary to foot clearance and toe tripping. These two data points indicate fall risk increases dramatically when step lengths are not consistent or bilaterally symmetrical.
If a person has been identified with step length variability or consistency issues, then a thorough gait analysis should be performed. In addition, a patient’s pain, ROM (range of motion), and strength should be assessed. If identified as related factors, they will have a much larger impact on step length variability and should be immediately addressed prior to other gait strategies. Then, the therapist can address the step length variabilities with verbal cues and other strategies to treat the person.
Using AI for Accurate Gait Analysis
By utilizing technologies like VSTBalance, clinicians can identify mobility deficits in older adults to determine if they are at risk of falling within the next 12 months. It uses artificial intelligence and machine vision that collects hundreds of data points, including step length and its associated variabilities, to help clinicians determine the best course of treatment to improve overall function and stay healthy. The VSTBalance system also runs mCTSIB and provides a detailed report identifying which balance system is underperforming. Regular assessments with VSTBalance ensure that each test is accurate and true patient progression can be tracked with confidence.