The Art and Science of Observational Gait Analysis

To elevate the level of clinical practice, practitioners need to combine subjective assessment with skill proficiency and submit their best  efforts to rigorous objective study.

A few years ago I ordered a novel titled Blink from Amazon for my leisure reading. Due to a shipping error I received a different book titled Blink, the Art of Thinking Without Thinking by Malcolm Gladwell. The title caught my attention, so I decided to read it. It was a good decision. Gladwell is a phenomenal writer, with an ability to condense big ideas into a concise and entertaining format.

In Blink Gladwell explains “rapid cognition,” and advances the idea that decisions made quickly and with limited information are often superior to those made over a long period of time with a large amount of data. Gladwell uses examples from the worlds of art, improv comedy, marriage counseling, auto sales, food tasting, law enforcement and medicine in support of this idea.

Gladwell contends not only that all of us make many important decisions every day in less than 2 seconds (in the blink of an eye), but that those decisions are often better than the ones we make when we take more time to evaluate more data. The key to rapid cognition lies in the sub conscious recognition of patterns based on “thin slices” of information. This is contrasted with consciously observing and evaluating data.

 
 
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Thin slicing and observational gait analysis

While reading the book I kept thinking that “thin slicing” was an accurate description of what orthotists and prosthetists do every day. In particular, I began to understand observational gait analysis as a thin slicing process. It’s not that rational processes have no part in observational gait analysis. It’s that the rational processes inform a core base of knowledge that kicks into gear in an intuitive way when we observe a patient walk.

Think about it this way: When observing someone without pathology walking at normal speed we have less than two seconds to observe a complete gait cycle. Even at the reduced speeds common in pathological gait, all evaluation of critical events must occur in increments of less than 2 seconds. We may observe a patient take multiple steps, but the key events we are observing in each of those steps are evidenced for only fractions of a second.

There is no way to collect and evaluate this data objectively without the aid of technology, and many of those solutions are of limited value in day-to-day clinical practice. Gait labs, for instance, are typically used for research, not to evaluate individual patients for treatment. A video camera with slow motion replay or the Instrumented Smart Pyramid can facilitate the assessment process, but most practitioners don’t use those tools on every patient.

So we thin slice. We identify patterns in normal and pathological gait — pathologies, deformities and motions that often go together. We even name those patterns: internal and external rotary deformity, toe walking, crouched gait, Trendelenburg gait, vaulting, etc. Through conscious study and experience we form a mental database of this information, and then intuitively identify those patterns quickly when we evaluate a patient in a clinical setting.

How good is your rapid cognition

Whether we agree with Gladwell’s presentation and conclusions about thin slicing or not, there’s no question that day-to-day clinical practice involves making decisions based on subjective assessment and limited objective data. The question is not whether we rely on rapid cognition, thin slicing and intuition in clinical practice, but how good we are at doing that.

How well does our thin slicing match the reality of each patient’s condition? How good are we at observing what is actually happening? Are our observations valid? Most importantly, are we even looking for the right things? Are we seeing what is actually there, or what we want to see?

Often we’re looking at insufficient data or the wrong data. Consider the common drop foot deformity. If we get in the habit of evaluating drop foot as only a swing phase deformity, we can miss very important stance phase consequences of weak dorsiflexors, not to mention proximal weakness. And if we’re not looking for those problems, chances are we aren’t offering orthotic designs that can positively affect them.

When intuition fails

Rapid cognition is a poor strategy if someone is inexperienced, poorly trained or has biases that are undetected or unchallenged. Racism is one example of failed thin slicing. Gladwell’s own interest in the subject of intuition began when he noticed a dramatic increase in the number of times he was stopped and questioned by police after he grew an Afro.

As clinicians we all have biases that negatively impact our assessments and can result in poor outcomes. Have you ever noticed that your competitors’ orthoses and prostheses don’t look quite as good as yours? That bias in favor of our own products and against those made by another provider can easily affect our subjective assessment of the functional outcomes we provide.

In order for thin slices of data to provide a sound basis for decision making they have to be the right slices of information. And we have to be trained how to gather and use that information. If this sounds a little circular to you, rest assured that Gladwell has come under criticism for this very reason. How can we know if the data we are focusing on is the right data?

This can raise doubts about the value of our personal assessment as clinicians. As clinicians is it wise to rely on our subjective assessment at all? Is gait analysis such a complicated process that it requires a highly controlled environment like a gait lab in order to have any credibility in our clinical process? Can I trust my own observation and the decisions I make based on that observational gait assessment?

 
 
 

Intuition can be trained

The answer to these questions is “yes,” because our intuitive decision process can be trained. The strict dictionary definition of “intuition” is a little extreme, according to the Free Dictionary: “knowing or sensing without the use of rational processes.” The truth is that intuition doesn’t act completely independent of rational thought. Our conscious and rational thought processes are constantly informing our intuition, and vice-versa.

When we practice a skill, we become better at using that skill in the 2-second increments that make up thin slicing. This may sound contradictory, but the more we break down a complex skill and practice the individual parts, the better we are at drawing on that training to form meaningful conclusions in the blink of an eye.

Intuition and evidence based practice

Both objective data and subjective assessment are important parts of evidence based practice. According to David Sackett’s definition:

“Evidence based medicine is the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients. The practice of evidence based medicine means integrating individual clinical expertise with the best available external clinical evidence from systematic research. By individual clinical expertise we mean the proficiency and judgment that individual clinicians acquire through clinical experience and clinical practice.”

Elevating the level of our clinical practice does not involve rejecting subjective assessment. It means recognizing the place of “proficiency and judgment,” educating ourselves and submitting our best efforts to rigorous objective study.

Gait assessment involves a lot of intuition, and intuition can be trained. The next question is, how are you and I training our intuition? Most of us combine our initial formal training in gait assessment with experience over time, but rarely go back and acquire more formal education. The problem is that without ongoing conscious training we may be repeating the same flawed or biased evaluation process over and over.

Academy Gait Society Initiatives

The Academy of Orthotists and Prosthetists (AAOP) offers many continuing education opportunities that provide a great way to train our intuition. The mission of the Academy Gait Society is “…to promote gait analysis as a method for advanced clinical care and research and to further educate orthotists, prosthetists and other medical professionals about the analysis and treatment of gait disorders.”

 
 
 

The Gait Society has developed several initiatives in 2012 that are designed to help us accomplish this mission. To put it in “Blink” terms: The intent of the initiatives is to train our rapid cognition.

  • · Journal Club. The Gait Society networking site allows practitioners to post and review content, and network with other professionals from around the globe. Shane Wurdeman, CP, MSPO and Elisa de Jong, CPO regularly select and post articles to the site. Shane provides a summary of the article along with his insights as a researcher in a gait lab.
    Over the past year the Journal Club has considered articles that address the issues of ankle orthoses and balance, AFO designs for Posterior Tabial Tendon Dysfunction, prosthetic suspension and the impact of ankle units on the gait of bilateral transtibial amputees. Reading these articles and participating in the discussion can add to our knowledge base about gait assessment and make us better at clinical decision making.
  • · Text Book Club. Sarah Sawers, CPO is coordinating the efforts of a group of practitioners who will read and discuss Christopher Kirtleys’ book “Clinical Gait Analysis.” This text contains solid research-based content that is accessible to clinicians, and provides a great way to improve our familiarity with the basic building blocks of gait assessment. Contact Sarah at sarahsawers@hotmail.com if you are interested in participating.
  • · The Gait Assessment Project. The GAP is a challenge to perform and document a formal gait assessment on two to three patients per week for 6 months. Participants can develop their own assessment and documentation form, or choose from among several options provided by the Gait Society. There will be opportunities to discuss with other practitioners how the project is affecting your clinical process.

Conclusion

There are many reasons to improve our gait assessment skills. Obviously the primary one is to improve our clinical decision making and outcomes for our patients. Other reasons include improving our communication with other health care professionals and justifying our recommendations to payers. Whatever our motivation, we should be striving to improve our subjective assessment skills (clinical intuition) and training our intuition by exposure to objective, rational and conscious thought.

A core group of practitioners from around the country is already forming around the Gait Society initiatives. Participation in the projects will be open at the AAOP annual meeting. Get involved in these initiatives and train your intuition. And then continue to practice the art of orthotics and prosthetics with confidence.

For more information:

John T. Brinkmann, CPO, LPO, FAAOP is Gait Society chair for the American Academy of Orthotists and Prosthetists and clinical coordinator of prosthetics and orthotics at Rockford Orthopedic Associates, Rockford, Ill. He may be reached at johnbrinkmanncpo@gmail.com.

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