The aim was to investigate the effects of three anatomical frames using palpable anatomical landmarks of the knee on the net knee joint moments. The femoral epicondyles, femoral condyles, and tibial ridges were used to define the different anatomical frames and the segment end points of the distal femur and proximal tibia, which represent the origin of the tibial coordinate system. Gait data were then collected using the calibrated anatomical system technique (CAST), and the external net knee joint moments in the sagittal, coronal, and transverse planes were calculated based upon the three anatomical frames. Peak knee moments were found to be significantly different in the sagittal plane by approximately 25% (p ≤ 0.05), but no significant differences were seen in the coronal or transverse planes. Based on these findings it is important to consider the definition of anatomical frames and be aware that the use of numerous anatomical landmarks around the knee can have significant effects on knee joint moments.
Dominic Thewlis, Jim Richards and Judith Bower
Fabian Mager, Jim Richards, Malika Hennies, Eugen Dötzel, Ambreen Chohan, Alex Mbuli and Felix Capanni
Forefoot stiffness has been shown to influence joint biomechanics. However, little or no data exist on metatarsophalangeal stiffness. Twenty-four healthy rearfoot strike runners were recruited from a staff and student population at the University of Central Lancashire. Five repetitions of shod, self-selected speed level walking, and jogging were performed. Kinetic and kinematic data were collected using retroreflective markers placed on the lower limb and foot to create a 3-segment foot model using the calibrated anatomical system technique. Ankle and metatarsophalangeal moments and angles were calculated. Stiffness values were calculated using a linear best fit line of moment versus of angle plots. Paired t tests were used to compare values between walking and jogging conditions. Significant differences were seen in ankle range of motion, but not in metatarsophalangeal range of motion. Maximum moments were significantly greater in the ankle during jogging, but these were not significantly different at the metatarsophalangeal joint. Average ankle joint stiffness exhibited significantly lower stiffness when walking compared with jogging. However, the metatarsophalangeal joint exhibited significantly greater stiffness when walking compared with jogging. A greater understanding of forefoot stiffness may inform the development of footwear, prosthetic feet, and orthotic devices, such as ankle foot orthoses for walking and sporting activities.
Jonathan Sinclair, Jim Richards, James Selfe, James Fau-Goodwin and Hannah Shore
The current study aimed to comparatively examine the effects of minimalist, maximalist, and conventional footwear on the loads experienced by the patellofemoral joint during running. Twenty male participants ran over a force platform at 4.0 m×s–1. Lower limb kinematics were collected using an 8-camera motion capture system allowing patellofemoral kinetics to be quantified using a musculoskeletal modeling approach. Differences in patellofemoral kinetic parameters were examined using one-way repeatedmeasures ANOVA. The results showed the peak patellofemoral force and pressure were significantly larger in conventional (4.70 ± 0.91 BW, 13.34 ± 2.43 MPa) and maximalist (4.74 ± 0.88 BW, 13.59 ± 2.63 MPa) compared with minimalist footwear (3.87 ± 1.00 BW, 11.59 ± 2.63 MPa). It was also revealed that patellofemoral force per mile was significantly larger in conventional (246.81 ± 53.21 BW) and maximalist (251.94 ± 59.17 BW) as compared with minimalist (227.77 ± 58.60 BW) footwear. As excessive loading of the patellofemoral joint has been associated with the etiology of patellofemoral pain symptoms, the current investigation indicates that minimalist footwear may be able reduce runners’ susceptibility to patellofemoral disorders.