For students and new grads, “biomechanics” can feel like a long list of tests. A more helpful way to think about it is this: you are trying to explain what moves, how it moves, and where the load ends up. When you document your findings, you’ll usually do it in two styles: qualitative (clear categories like inverted/parallel/everted) or quantitative (numbers you can measure and repeat). The goal is not to pick a side—it’s to choose the level of detail that helps you make (and defend) a clinical decision.
A simple framework keeps you organised: kinematics, kinetics, and plantar pressure.
• Kinematics = the motion you can see (positions, angles, timing).
• Kinetics = the loading behind that motion (forces and moments).
• Pressure = a practical way to see where load is concentrated under the foot the easiest way is to observe the pressure marks on a sock liner (Quantitively via plantar pressure mapping, in-shoe or platform). [1,2]
Here’s why this matters: two patients can look similar kinematically (both “pronate”), but one may have a very different kinetic/pressure story—higher medial forefoot load, longer time on the first ray, or a persistent hotspot—so their symptoms and orthotic priorities may be different.
Qualitative biomechanics is what you do every time you say, “this looks everted,” or “they collapse medially.” It is fast, it fits a busy clinic, and it’s often enough to start treatment—especially early in your career.
How to think qualitatively (quick checklist):
1) Kinematics: What direction is the rearfoot/tibia/forefoot moving? Use consistent categories (inverted/parallel/everted; neutral vs. relaxed).
2) Kinetics: Where do you suspect the tissues are being stressed? For example: “medial column overload,” “high pronation demand,” or “low supination resistance.” (You’re describing loading patterns, not claiming exact forces.) [3]
3) Pressure: Where is the wear/hotspot? Even without a pressure system, clues include callus patterns, insole wear, and patient-reported hotspots. If you do have pressure mapping, a simple note like “medial forefoot hotspot” or “prolonged hallux loading” can be very clinically useful.
Quantitative biomechanics uses numbers to make your observations more repeatable and easier to compare (left vs. right, pre vs. post, baseline vs. follow-up). The trap for beginners is “false precision”—recording a number that you can’t reliably reproduce next time.
Good beginner-friendly quantitative options:
• Kinematics: measure angles you can landmark consistently (for example, tibia-to-calcaneus in stance) and document the position you used (neutral vs. relaxed).
- Kinetics: true forces/moments usually require a lab, but you can still quantify proxies in a repeatable way (for example, a standardised supination resistance grading, timed single-leg heel raise, or step-down tolerance—whatever your clinic uses consistently). [3]
• Pressure: if you have plantar pressure mapping, pick a small set of variables you’ll actually re-check—commonly peak pressure, pressure-time integral, and contact area in key regions (heel, medial forefoot, hallux). [1,2]Rule of thumb: only measure what you expect to change your plan (orthotic design, footwear advice, exercise focus) or what you need to track change over time.
No matter how you chart, your results are only as good as your landmarks. That’s why tibial and calcaneal bisections matter so much in training: they help you aim at bone alignment rather than “what the skin looks like today.” [4]
For qualitative charting: bisections help you build a consistent “eye,” so inverted/parallel/everted means the same thing each time you write it.
For quantitative charting: bisections reduce day-to-day variability—if you can’t re-find the same reference line, the number you record is not very meaningful. Broader lower-limb biomechanical measures also tend to show better within-rater than between-rater repeatability, which is another reason to be consistent with your own technique and documentation. [5]
And when you’re using pressure information, consistent kinematic landmarks help you connect the dots: where the load shows up (pressure) should make sense with how the limb is positioned and moving (kinematics) and the stress pattern you’re trying to change (kinetics).
So, should you chart qualitatively or quantitatively? For most new grads, a good progression is: start qualitative, then add numbers when you need them.
Use mostly qualitative when you are screening patterns, forming an initial hypothesis, or making a same-day decision (for example, “rearfoot everted in relaxed stance + medial forefoot hotspot = likely medial overload pattern”).
Add quantitative when you need repeatability: follow-ups, comparing interventions (shoe change vs. orthotic change), communicating clearly with another clinician, or when the patient asks, “Is it actually improving?” That’s where measured angles, repeatable functional tests, and pressure metrics can show whether loading distribution and tissue stress markers are shifting in the direction you intended.
Practical takeaway (student template):
1) Kinematics (motion): Neutral vs. relaxed, and a simple category (inverted/parallel/everted). Add a measured angle only if you can reproduce your landmarks.
2) Kinetics (loading hypothesis): One sentence on the likely stress pattern (e.g., “medial column overload” / “high pronation demand” / “low supination resistance”), plus one repeatable test or observation that supports it. [3]
3) Pressure (where load shows up): hotspot/callus/wear pattern, or—if available—pressure metrics in the region that matches the symptoms (peak pressure, pressure-time, contact area). [1,2]
Qualitative and quantitative charting are not competing philosophies. They are two ways to describe the same system: motion (kinematics) + loading (kinetics) + load distribution (pressure). Start simple, be consistent, and measure only what improves your clinical decisions or your ability to track change. When you do change footwear/insoles/orthotic materials, pressure metrics can help show whether loading actually shifted. [6]
References
- Parker D, Andrews J, Price C. Validity and reliability of the XSENSOR in-shoe pressure measurement system. PLoS One. 2023;18(1):e0277971. doi:10.1371/journal.pone.0277971.
2. Castro-Martins P, Marques A, Coelho L, Vaz M, Santos Baptista J. In-shoe plantar pressure measurement technologies for the diabetic foot: a systematic review. Heliyon. 2024;10(9):e29672. doi:10.1016/j.heliyon.2024.e29672.
3. Griffiths IB, McEwan IM. Reliability of a new supination resistance measurement device and validation of the manual supination resistance test. J Am Podiatr Med Assoc. 2012;102(4):278-289. doi:10.7547/1020278.
4. LaPointe SJ, Peebles C, Nakra A, Hillstrom H. The reliability of clinical and caliper-based calcaneal bisection measurements. J Am Podiatr Med Assoc. 2001;91(3):121-126. doi:10.7547/87507315-91-3-121.
5. Van Gheluwe B, Kirby KA, Roosen P, Phillips RD. Reliability and accuracy of biomechanical measurements of the lower extremities. J Am Podiatr Med Assoc. 2002;92(6):317-326. doi:10.7547/87507315-92-6-317.
6. Gerrard JM, Bonanno DR, Whittaker GA, Landorf KB. Effect of different orthotic materials on plantar pressures: a systematic review. J Foot Ankle Res. 2020;13:35. doi:10.1186/s13047-020-00401-3.