SLR - November 2021 - Alex Pilkinton
Reference: Marouvo J, Sousa F, Fernandes O, Castro MA, Paszkiel S. Gait Kinematics Analysis of Flatfoot Adults. Applied Sciences. 2021; 11(15):7077. https://doi.org/10.3390/app11157077Level of Evidence: 3
Scientific Literature Review
Reviewed By: Alex Pilkinton, DPM
Residency Program: Crozer-Chester Medical Center – Upland, PA
Podiatric Relevance: One of the basic foundations for podiatric physicians is a sound knowledge of foot and ankle biomechanics. Foot and ankle biomechanics lay the groundwork for choosing which surgical intervention to perform, and for predicting potential pathomechanical forces that result from certain foot types in the prevention of deformity recurrence and limb salvage. Many studies exist that investigate foot and ankle biomechanics, but not as many studies exist that cover biomechanics throughout the entire lower extremity. The purpose of this study was to compare kinematic differences among people with flatfoot vs neutral foot morphology along the entire lower extremity.
Methods: This research included an observational study of 31 eligible participants (15 flatfoot and 16 neutral foot type) at the Polytechnic Institute of Coimbra. Inclusion criteria consisted of subjects between the ages of 18 and 40 years old with a flatfoot or neutral foot type and no prior trauma or condition found to influence gait or muscle activity to the foot. Flatfoot was defined as a foot type that exhibited >9 millimeters of navicular drop height with weight bearing and >4 degrees of eversion in resting calcaneal stance position, and neutral being defined as 5-9 millimeters navicular drop height with weight bearing and <4 degrees calcaneal eversion in RCSP. All participants had 3D gait analysis performed with tracking markers placed to the head, thorax, and lower extremities, and 10 gait passages were submitted for evaluation. Statistical analysis of kinematic data was used to compare ankle, hip, knee, and pelvis angles and peak range of motion among limb segments, as well as the excursion of center of mass.
Results: Statistically significant kinematic differences between flatfoot vs. neutral foot measure included less ankle peak dorsiflexion, abduction, internal, and external rotation, as well as, a decrease in hip and knee peak extension. However, flatfoot individuals displayed greater hip and knee peak flexion and range of motion as compared to neutral footed individuals. Center of mass in respect to maximal vertical displacement was statistically different between the two sample groups with flatfoot individuals displaying lower percentage of displacement.
Conclusions: The authors conclude that alterations throughout the entire gait cycle were visualized with kinematic analysis of the lower extremity limb segments comparing flatfoot individuals to neutral foot individuals. Knowing that flatfooted individuals display significantly less ankle dorsiflexion and higher peak knee flexion angles can explain anterior knee pain that a patient may have from such a weight bearing limb acting as a functional limb length discrepancy. This information could be used to enhance an athlete’s athletic performance as well, noting that flatfoot kinematics yield lower knee and hip extension that would be ideal in the development of power with toe-off in stride. The data presented in this paper suggest that supporting a flatfoot with added arch support in gait would increase power output, thereby, improving speed characteristics in addition to offloading tendon, joint, and ligament stress secondary to deformity.