How Can We Make Biomechanics Relevant To Podiatric Residency Training?

I often hear my colleagues boast that podiatrists, in comparison to our orthopedic colleagues, are uniquely trained to perform foot and ankle surgery. They largely base this belief upon an assumption that podiatrists understand the function of the foot better than any other medical specialty. It is true that the unique training podiatric students and residents receive in the field of biomechanics previously bestowed a superior ability to apply functional principles to foot and ankle surgery. 

But is this still true today?

The definition of the term biomechanics is “the study of the structure, function and motion of the mechanical aspects of biological systems, at any level from whole organisms to organs, cells and cell organelles using the methods of mechanics.”¹ Using this definition, one could describe podiatric biomechanics as a discipline devoted to understanding the structure, function and motion of the foot and ankle.

Why is there a steady decline in the teaching of biomechanics?

In a recent blog, I pointed out the decreasing emphasis on education and training in biomechanics over the past 30 years in podiatric medical schools in the United States.² Furthermore, postgraduate education in biomechanics, whether it is via podiatric residency or continuing medical education programs, has all but vanished in my opinion. This dire situation may become dramatically worse with the reduction of number of biomechanics cases required by the Council on Podiatric Medical Education (CPME) for podiatric residency training.³

For some reason, biomechanics has become the poor stepchild of podiatric medical education. A significant contributor to the problem, in my opinion, is the shortsighted perception among my colleagues that podiatric biomechanics is a field limited to the study and implementation of foot orthotic therapy. I often hear esteemed leaders and educators in the podiatric profession refer to the discipline of biomechanics as the study of foot orthotic therapy. While foot orthotic therapy is only a small part of the study of biomechanics, even this treatment option appears to be falling out of favor among foot and ankle surgeons as a viable part of their treatment regimens.  

For many years, I served as Section Editor-Sports Medicine for the Journal of Foot and Ankle Surgery (JFAS). During that time, manuscripts submitted to JFAS regarding the subject of biomechanics would typically be assigned to the sports medicine section for review. These manuscripts included studies of the mechanical effects of surgical procedures using gait analysis, 3-D kinematics, joint moment measures and plantar pressure mapping. As I had no qualified reviewers with expertise in these subject areas, I lobbied for the establishment of a new editorial subsection to review all submissions related to biomechanics. The answer from the JFAS managerial committee was that a new subsection devoted to foot orthotics was not necessary for a surgery journal.

Emphasizing How Biomechanical Fundamentals Impact Decision-Making In Foot And Ankle Surgery 

Two years ago, I was honored to receive an invitation to write the lead chapter entitled “Biomechanics” for the forthcoming new edition of McGlamry’s Operative Textbook of Foot and Ankle Surgery (Wolters Kluwer). This was a refreshing breakthrough as this prestigious textbook would, for the first time, incorporate a chapter devoted to the subject of biomechanics. At the same time, writing this chapter was a daunting task for me as the general field of “biomechanics” is quite broad and includes many subtopics that may not be of interest to the foot and ankle surgeon. 

Ultimately, I asked myself, “What topics in the field of biomechanics are most relevant to the foot and ankle surgeon?” Ironically, I decided to not discuss foot orthotic therapy. Instead, I chose to review the essential phases of walking gait and then presented more recent research showing the individual motion of the bones of the foot across all the major articulations. I further reviewed the phasic activity and moment arms of all the muscles of the lower leg and foot. Finally, it became clear that a section on the sensorimotor system was critically important because this ultimately controlled the net movement of the foot during ambulation. I tried to bring relevance to these topics by showing how altered mechanics can lead to pathology and how pathology can alter the normal mechanics of the foot and ankle.  

In reality, writing this book chapter led to the revelation of the need for a new textbook in podiatric biomechanics, which focused on the pathomechanics of disorders of the foot and ankle. This became a two-year project culminating in the publication of my new book titled Pathomechanics of Common Foot Disorders, published by Springer Nature.⁴ It is now clear to me that only after learning biomechanics can a clinician understand the pathomechanics of lower extremity pathology. Without understanding the pathomechanics causing the disorder, how can a surgeon develop a proper treatment approach?

What Should Residents Know About Biomechanics Prior To And During Residency Training?

With current podiatric residency training being heavily weighted toward surgical training, there has been a continuous decline in the study of biomechanics within the entire educational process for podiatry residents. As I pointed out in my recent blog, the CPME 320 Standards and Requirements for Approval of Podiatric Medicine and Surgery Residencies is quite vague in describing the specific training that podiatric residents need in the field of biomechanics.^2,5 

In the proposed draft of the changes to the CPME 320 document, requirement 6.0 designates a competency in biomechanics, which does outline some forms of treatment: “Perform biomechanical examination and manage patients with lower extremity disorders utilizing a variety of prosthetics, orthotics, and footwear.”^2,5 Again, despite the broad range topics for study in the field of biomechanics, it appears that the direct application of this discipline in podiatric residency training is limited to orthotic therapy and footwear.   

In reality, the podiatric resident should have already completed thorough didactic training in all aspects of lower extremity biomechanics by the time he or she graduates from podiatric medical school. Therefore, a student coming into a podiatry residency program should be fully competent in performing gait analysis, muscle testing, measurement of joint range of motion and foot posture assessment. Podiatry residents should be well versed in reading and understanding research of foot function using 3-D kinematic studies, force plates and plantar pressure measurements. Furthermore, they should have comprehensive education in the pathomechanics of foot and ankle disorders. Pathomechanics is really the clinical application of biomechanics. It is about how aberration in the mechanical function of the lower extremity can cause various pathologies. Pathomechanics is also the study of how injuries and disease alter normal function of the lower extremity. 

In my opinion, a requirement must exist for the podiatric resident to use his or her training in biomechanics and pathomechanics to evaluate and treat each and every patient they encounter during their three years of post-graduate training. This should not be limited to only 50 cases but instead should apply in all cases. 

Prior to scrubbing, assisting or even performing the actual surgery, the podiatric resident should identify any and all contributing factors to the pathomechanics of the pathology being addressed. The identification of all extrinsic and intrinsic risk factors should take place pre-operatively including a review with the attending surgeon beforehand. In short, all podiatric residents should know how the pathology developed and what risks remain for recurrence after the performance of the surgical procedure. How can you fix a problem if you cannot identify how it happened in the first place?

For example, the residents should exhibit the ability to identify the contributing factors for hallux abductovalgus (HAV) deformity in each and every patient whose case they participate in. Given the multifactorial etiology of HAV deformity, residents should be able to identify the specific contributing factors in individual cases. Constrictive footwear does not cause all bunions. Is there an underlying flatfoot deformity? Is there significant metatarsus adductus? Is there excessive transverse plane motion at the first tarsometatarsal joint? Is there generalized ligamentous laxity? Is there weakness of the abductor hallucis muscle?

In Conclusion

Whether one is performing wound care, doing reconstructive surgery, treating sports injury or addressing a trauma case, all foot and ankle and ankle surgeons must learn that most pathologies they treat have a mechanical basis in their etiology. Why shouldn’t residents identify the mechanics or, actually, the pathomechanics of these conditions in each and every patient encounter during podiatric residency training?

Dr. Richie is an Adjunct Associate Professor within the Department of Applied Biomechanics at the California School of Podiatric Medicine at Samuel Merritt University in Oakland, Calif. He is a Fellow and Past President of the American Academy of Podiatric Sports Medicine. Dr. Richie is a Fellow of the American College of Foot and Ankle Surgeons, and the American Academy of Podiatric Sports Medicine. Dr. Richie is the author of a new book titled "Pathomechanics of Common Foot Disorders," which is available from Springer at https://www.springer.com/us/book/9783030542009 .

References

1.  Wikipedia. Biomechanics. Available at: https://en.wikipedia.org/wiki/Biomechanics . Accessed December 28, 2020.

2.  Richie D. Proposed CPME 320 changes may dramatically reduce required biomechanics cases in residency training. Podiatry Today. Available at: https://www.podiatrytoday.com/blogged/proposed-cpme-320-changes-may-dramatically-reduce-required-biomechanics-cases-residency . Published December 2, 2020. Accessed December 28, 2020.

3. Council on Podiatric Medical Education. CPME 320 and 330 revision in progress. Available at: https://www.cpme.org/residencies/content.cfm?ItemNumber=29729&navItemNumber=15094 . Accessed December 28, 2020.

4.  Richie D. Pathomechanics of Common Foot Disorders. New York: Springer US; 2020. 

5.  Council on Podiatric Medical Education. Standards and requirements for approval of podiatric medicine and surgery residencies. Available at: https://www.cpme.org/files/CPME/CPME%20320%20Updated%20May%202020.pdf . Published July 2018. Accessed December 28, 2020.