Impact-Related Ground Reaction Forces Are More Strongly Associated With Some Running Injuries Than Others

Abstract

Background: Inconsistent associations have been reported for impact-related ground reaction force variables and running injuries when grouping all injuries together. However, previous work has shown more consistent associations when focusing on specific injuries. Purpose: To compare ground reaction force variables between healthy and injured runners as a group and within specific common injuries. Study Design: Controlled laboratory study. Methods: A total of 125 runners presenting with patellofemoral pain, tibial bone stress injury, plantar fasciitis, Achilles tendinopathy, or iliotibial band syndrome and 65 healthy controls completed an instrumented treadmill assessment at a self-selected speed. Impact-related ground reaction force variables included vertical average (VALR) and instantaneous (VILR) load rates, posterior and medial/lateral instantaneous load rates, and vertical stiffness at initial loading (VSIL). Mean comparisons were made between the general and specific injury and control groups (α = .05). Cutoff thresholds were established and evaluated using several criteria. Results: VALR (+17.5%; P < .01), VILR (+15.8%; P < .01), and VSIL (+19.7%; P < .01) were significantly higher in the overall injured versus control groups. For individual injuries, VALR, VILR, and VSIL were significantly higher for patellofemoral pain (+23.4%-26.4%; P < .01) and plantar fasciitis (+17.5%-29.0%; P < .01), as well as VSIL for Achilles tendinopathy (+29.4%; P < .01). Cutoff thresholds showed better diagnostic criteria for individual versus grouped injuries. Conclusion: Impact variables (VALR, VILR, and VSIL) were significantly higher when assessing the injured group as a whole. However, these findings were driven by specific injury groups, highlighting the importance of taking an injury-specific approach to biomechanical risk factors for running injury. Clinical Relevance: These results suggest that practitioners may want to address impact loading in their treatment of injured runners, especially in those with patellofemoral pain and plantar fasciitis.

Leg Stiffness, Joint Stiffness, and Running-Related Injury: Evidence From a Prospective Cohort Study

“…While stiffness has been associated with greater overall injury risk in previous work, 22 emerging research suggests that some biomechanical risk factors are only relevant for certain injury locations. 18 Although our results suggest stiffness may not be a major factor in overall injury risk, further research using clinician-confirmed injuries may be warranted to identify tissue-specific associations between stiffness and injuries to specific load-bearing tissues (e.g., patellofemoral joint, tibia).…”

Relationship between duty factor and external forces in slow recreational runners

“…15 Moreover, the risk of RRI rises more sharply when the magnitude of the loading is increased compared with an increase in the amount of steps taken, 16 emphasising the detrimental effect of too high a loading on the musculoskeletal system. Although internal forces contribute most to the experienced loading, 17 18 external ground reaction forces (GRFs) can be used as operational measures as they reflect these internal forces during level running (FzMax: maximal vertical GRF, [17][18][19][20] or because they are directly identified as risk factors of RRI (peak braking force (PBF) 21 22 and vertical instantaneous loading rate (VILR) [23][24][25][26][27] ). These external force measures relate mechanically to a runners' running style (eg, refs 28 29).…”

Wearable Technology May Assist in Retraining Foot Strike Patterns in Previously Injured Military Service Members: A Prospective Case Series

“…Overall, we achieved favorable reductions in AVLR in those with knee complaints with a NRFS transition using an instrumented sock. Our results contribute to an evolving body of literature advocating for an injury-specific approach to biomechanical risk factors for injury (Johnson et al, 2020). At follow-up, the participants demonstrated reduced ground stance time during running.…”

“…It is well documented that AVLRs are greater in individuals who run with a RFS pattern versus a non-rearfoot strike pattern (NRFS) (Lieberman et al, 2010;Zadpoor and Nikooyan, 2011;Goss and Gross, 2013;Almeida et al, 2015;Goss et al, 2015;Miller et al, 2020;Xu et al, 2020). Of note, AVLRs greater than 70 BW/s have been associated with tibial and metatarsal stress fractures (Zifchock et al, 2006;Zadpoor and Nikooyan, 2011), patellofemoral pain syndrome (Johnson et al, 2020), and plantar fasciitis (Pohl et al, 2009). It is plausible that altering running biomechanics to reduce AVLR, and thereby improving shock attenuation, may be beneficial in the treatment and prevention of injuries (van der Worp et al, 2016).…”