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Peak Performance Physical Therapy & Sports Training EVIDENCE-BASED PRACTICE UPDATE June 2022 Using 2D Video Testing with Runners - Analyzing Biomechanics to Treat and Prevent Injury CLINICAL SCENARIO…What do you think? A 35 year old runner comes in with L lateral knee pain gradually developing and worsening over time as running mileage has increased and hilly terrains have been added to workouts of 4-5d/wk running. She has (B) mild squinting patella in resting standing, worsened slightly in single leg stance, over pronation L > R in single leg balance, painful single squat from ~ 150 - 400, (-) Ober’s and McMurray’s, unremarkable plain films, and local tenderness over the ITB at the lateral femoral condyle. You refer her for ITBS with orders to evaluate and treat. She’s returning for a 4 week FU and here’s what she tells you about her PT experience so far … A. Did a 10min evaluation and provided her with the clinic’s ITB Syndrome exercise sheet including 3 different ITB stretches, 4” step ups, clam shells. No major changes yet. Sore after step ups but PT said it may hurt for a few weeks and then should begin reducing pain. B. Did a 45 minute evaluation and found less L knee valgus/femoral IR/pronation with medial posting an OTC insert, noted L STJ neutral squat DF loss (prior ankle sprain hx) - doing ankle mob’s and soleus stretching, customized depth of step downs to 1” box to avoid pain during quads training, doing Class IV laser now, working hip ER’s in wb. Sx 40-50% reduced now. Treadmill assessment planned once sx reduced to allow jogging. C. Did 20min evaluation and began with instrument assisted “scraping” technique tissue mobilization to ITB, ultrasound, resistance band walks, NWB inversion tubing to strengthen foot along with towel toe scrunches for intrinsics. Sx 10-20% better. PT requesting script for iontophoresis. What would you decide for each case? 1. Determine the therapy is not specific/customized enough, the eval was too cursory and treatments are not biomechanically focused. Consider allowing 2 -3 more weeks of care before changing (or change now) to a PT/clinic doing more in-depth biomechanical testing and customized exercise. 2. The treatments are appropriate and on track. Happy with present status. Advise to continue PT. 3. Concerned about the lack of more thorough evaluation and use of generic and assumed local ITB approaches (stretches, soft tissue work) despite no (+) ITB tightness findings. Contact the PT to discuss the case and to question if underlying causes/factors identified and what further testing is planned. 4. Order an MRI to R/O a degenerative lateral meniscus tear or small chondral lesion that may be causing the lateral knee pain. Summary: Physicians and physical therapists frequently see runners for their most common issue, lower extremity injuries. If “overuse” is really to blame, knowing running is a bilateral reciprocating activity, then why are these injuries so often unilateral? Physicians routinely send runners for physical therapy. The real key is what happens next. As a physician, do you really know? Is a patient who comes back “feeling better” truly better? How do we get beyond simply treating the pain/inflammation and actually identifying biomechanical causes or technique based issues that may be contributing to the diagnosis made? Is the naked eye adequate in identifying these issues with treadmill or on-ground running analysis? The use of 2D video testing can help identify areas needing further biomechanical and orthopedic assessment for tightness or weakness or poor neuromuscular control. They also provide excellent feedback for possible technique cues runners can implement to alter the abnormal forces being produced. The gold standard in visual recordings to understand the biomechanics during running can be done utilizing expensive 3D (sagittal, frontal/coronal, and transverse plane views) cameras/software but this must include the right operational setting, which is unobtainable by most therapists and their patients. More recently, 2D (sagittal and frontal plane) analysis has been increasing in availability as a practical way to help providers and runners observe individualized mechanics and form during running. This can aid to help better understand the faulty biomechanics potentially leading to the “overuse” injuries we hear patients report in the clinic. Martinez et al. compared sagittal plane 2D and 3D analysis of running kinematics and determined that the 2D measurements 2-50 from the gold standard 3D counterparts and can serve as an effective way to record qualitative and quantitative information that could not be seen easily by the naked eye alone. Maykut et al. in similar fashion looked at 2D vs. 3D in the frontal plane focusing on pelvis-hip-knee relationships and also found good validity and reliability vs 3D. In the mode of “practice what I preach”, I used 2D analysis on myself with the SPARK MOTION ™ app available at Peak Performance to analyze my running mechanics, helping to better understand what I may be doing well, and more obviously not well and perhaps identify reasons for the knee pain I get with increasing training and mileage. (We’d love to hear your professional insights on this topic. Let me know your thoughts after reading this summary at PT@PeakPTRochester.com or if you have a patient case you'd like to discuss) CURRENT EVIDENCE Martinez, Caitlyn, et al. "Comparison of 2-D and 3-D Analysis of Running Kinematics and Actual Versus Predicted Running Kinetics." International Journal of Sports Physical Therapy 17.4 (2022): 566-573. Background: It is crucial to have a tool such as 2D kinematic motion analysis to predict kinematic measurements in distance runners and is needed to compare accuracy vs 3D gold standard as well as measured and estimated kinetic variables. Method: 30 runners averaging at least 20 miles/wk ran on an instrumented treadmill at their preferred training pace for 6 minutes before having kinematic data measured by markers placed on anatomical landmarks on left LE then data collected on both 2D and 3D camera systems. Ground reaction forces (GRF) were also recorded as kinetic data to compare against published kinetic prediction formulas vs 2D and 3D measurements. Results: Significant difference did exist between 2D and 3D kinematic measurements however average difference for all 2D kinematic data was within 2-50. Previously published kinetic prediction equations were supported by both 2D and 3D measurements for GRF and loading rate. Author’s Conclusion: Accurate predictions of kinetic variables can be made using spatiotemporal and 2D kinematic variables. Maykut, Jennifer N et al. “Concurrent validity and reliability of 2d kinematic analysis of frontal plane motion during running.” International journal of sports physical therapy vol. 10,2 (2015): 136-46. Background: Due to temporal and financial constraints, concurrent reliability and validity need to be assessed for 2D analysis of runners in the frontal plane. Method: 24 collegiate cross country runners completed a protocol on a treadmill at a self selected speed with frontal plane (FP) data collected using 3D and 2D motion analysis systems. Variables of interest were contra-lateral pelvic drop (CPD) peak hip adduction angle (HADD), and peak knee abduction angle (KABD). Results: 2D analysis demonstrated excellent intra-rater reliability for peak HADD and CPD. Moderate correlations between HADD were noted between 2D and 3D of bilateral LEs and KABD on the left. No statistical significance between CPD between analysis however a strong correlation was present between HADD and CPD. Author’s Conclusion: The ease of 2D running analysis in capturing FP variables can be effective when assessing HADD and with close relations to CPD. THE PEAK PERFORMANCE PERSPECTIVE Andrew Neumeister, DPT, FAFS, CAFS, Certified Running Gait Analyst Physicians must scrutinize what the best options are for the treatment of runners with lower extremity pain. Simply addressing local symptoms with modalities along with rest and gradual return to activity may provide short term relief but not address underlying causes or reduce likelihood of recurrence. Biomechanical based testing, both from a local and global on-ground movement performance basis but also from a functional task analysis (i.e. treadmill or ground) of running itself can be a necessary tool in directing treatment needs. Runners are often considered a different “breed” l because from the external perspective…who enjoys running for the sake of running? But talking to and working with these individuals gives you an appreciation for the dedication they have towards their sport and the oftentimes stress that is willingly put on their bodies. Many runners end up with short or long term recurring injuries that are not easily improved with rest or general stretching. I have been fortunate enough to have had a fairly injury free running career transitioning from sprinting and 400m hurdles to the marathon and ultra-marathon distance post collegiate. As the evidence base for 2D running analysis has grown, it was time to practice what I preach and see what biomechanical flaws I may have with my running form and shed light on a fortunate brief battle with R knee IT band syndrome. Utilization of 2D analysis can provide a skilled practitioner with more specific biomechanical data to assist in both evaluating and treating the patient to more quickly hit the ground running… Martinez et al. accomplished some of the hypotheses they set out to test in the sagittal plane in regards to comparing 2D analysis against the gold standard of 3D. Despite statistical differences noted between leg angles, strong correlations were found between the variables. Variables of interest assessed for the left LE included shoe angle at initial contact, tibia to vertical at initial contact, knee flexion angle at initial contact and mid-stance and vertical position of center of mass at mid-stance and double float. The average difference between 2D and 3D variables were 1.4-4.90 depending on which kinematic angle measured which can provide benefit when assessed by a seasoned biomechanical clinician by assessing for kinetic flaws or potential pitfalls in the injured runner. With an acceptable mean of <50 difference between an affordable 2D analytic system and an impractical 3D motion capture setup for the clinic environment, abnormalities can be discovered that are not otherwise observed with the naked eye in real time. It thus becomes a powerful tool for evaluating and making treatment choices in order to counter biomechanical and/or technique shortcomings. Maykut et al. conducted a similar study to the one above, however looked at the frontal plane positions of the pelvis, femur, and tibia relative to each other and vertical. Again, the authors concluded that no statistical correlation was found between 2D and 3D analysis for pelvic drop and knee abduction, however, peak hip ADD had a strong correlation found and that HADD correlated with CPD. Intra-rater reliability was also found using 2D software and this knowledge allows a clinician to be confident in their observations to make sound decisions to better expedite recovery and return to activity. Peak Performance and Spark Motion™ Technology It is easy to glance over the results or discussion pieces in current literature and see that the authors failed to find statistical significance between certain variables and dismiss the data. Although 2D and 3D analysis is statistically different for many kinetic variables, moderate correlation was found for HADD in the frontal plane which is commonly associated with increased triplanar dynamic valgus (knee abduction, femoral IR, knee flexion). Almost all clinicians will agree that reducing dynamic valgus stress at the knee throughout impact and loading is pivotal for reducing risk of injury. The use of 2D motion capture technology gives clinicians the capability to slow down or even freeze frame and draw vectors to compare asymmetrical loading during a reciprocating activity. Being able to show someone who is having pain while running their own biomechanics and comparing left to right and/or versus normal mechanics is an extremely powerful tool to guide treatment of pathologies. This can be especially true for those with “overuse” injury because the asymmetries or abnormalities in their inherent biomechanics of running technique can be so small they are not otherwise evident. The images of me below are depicting commonly measured variables during 2D analysis in the frontal and sagittal planes performed in our office. One of these pictures may stand out more than the others when assessing running form and body positioning during initial contact, mid stance, and heel off. It may seem trivial when noticing the extent of abnormality/asymmetry when asked to pick it out of this collection below; however would this clear visual have been found without 2D running analysis??? How fast can you spot my mechanical pitfall that contributes to IT syndrome? Being able to “connect the dots” biomechanically is critical in not only helping patients overcome their present issue but also in providing confidence to patients and providers alike that the risk of recurrence has been greatly reduced! R Hip ADD Mid-stance L Hip ADD Mid-stance L Hip Extension Toe Off Tibial Inclination IC Knee Flexion IC 9 Deg DF Mid-stance 9 Deg Knee Flexion Mid-stance 35 Deg