Koren E Roach1, K Bo Foreman2, Bruce A MacWilliams3, Konstantinos Karpos4, Jennifer Nichols5, Andrew E Anderson6. 1. Department of Radiology and Biomedical Imaging, 185 Berry St., Suite 350, San Francisco, CA 94107, United States; Department of Orthopaedics, University of Utah, 590 Wakara Way, Salt Lake City, UT 84108, United States; Department of Biomedical Engineering, University of Utah, 72 Central Campus Dr, Salt Lake City, UT 84112, United States. 2. Department of Orthopaedics, University of Utah, 590 Wakara Way, Salt Lake City, UT 84108, United States; Department of Physical Therapy and Athletic Training, University of Utah, 520 Wakara Way, Suite 240, Salt Lake City, UT 84108, United States. 3. Department of Orthopaedics, University of Utah, 590 Wakara Way, Salt Lake City, UT 84108, United States; Motion Analysis Center, Shriners Hospitals for Children, 1275 Fairfax Rd., Salt Lake City, UT 84103, United States. 4. Department of Orthopaedics, University of Utah, 590 Wakara Way, Salt Lake City, UT 84108, United States; Department of Physics, Arizona State University, 550 E Tyler Drive Tempe, AZ 85287, United States. 5. Department of Orthopaedics, University of Utah, 590 Wakara Way, Salt Lake City, UT 84108, United States; J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, 1275 Center Drive, Gainesville, FL 32611, United States. 6. Department of Orthopaedics, University of Utah, 590 Wakara Way, Salt Lake City, UT 84108, United States; Department of Biomedical Engineering, University of Utah, 72 Central Campus Dr, Salt Lake City, UT 84112, United States; Department of Physical Therapy and Athletic Training, University of Utah, 520 Wakara Way, Suite 240, Salt Lake City, UT 84108, United States; Scientific Computing and Imaging Institute, University of Utah, 72 Central Campus Dr, Salt Lake City, UT 84112, United States. Electronic address: Aea4@utah.edu.
Abstract
BACKGROUND: Several multi-segment foot models have been developed to evaluate foot and ankle motion using skin-marker motion analysis. However, few multi-segment models have been evaluated against a reference standard to establish kinematic accuracy. RESEARCH QUESTION: How accurately do skin-markers estimate foot and ankle motion for the modified Shriners Hospitals for Children Greenville (mSHCG) multi-segment foot model when compared against the reference standard, dual fluoroscopy (DF), during gait, in asymptomatic participants? METHODS: Five participants walked overground as full-body skin-marker trajectory data and DF images of the foot and shank were simultaneously acquired. Using the mSHCG model, ankle and midfoot angles were calculated throughout stance for both motion analysis techniques. Statistical parametric mapping assessed differences in joint angles and marker positions between skin-marker and DF motion analysis techniques. Paired t tests, and linear regression models were used to compare joint angles and range of motion (ROM) calculated from the two techniques. RESULTS: In the coronal plane, the skin-marker model significantly overestimated ROM (p = 0.028). Further, the DF model midfoot ROM was significantly positively related to differences between DF and skin-marker midfoot angles (p = 0.035, adjusted R2 = 0.76). In the sagittal plane, skin-markers underestimated ankle angles by as much as 7.26°, while midfoot angles were overestimated by as much as 9.01°. However, DF and skin-marker joint angles were not significantly different over stance. Skin-markers on the tibia, calcaneus, and fifth metatarsal had significantly different positions than the DF markers along the direction of walking for isolated portions that were less than 10 % of stance. Euclidean distances between DF and skin-markers positions were less than 9.36 mm. SIGNIFICANCE: As the accuracy of the mSHCG model was formerly unknown, the results of this study provide ranges of confidence for key angles calculated by this model.
BACKGROUND: Several multi-segment foot models have been developed to evaluate foot and ankle motion using skin-marker motion analysis. However, few multi-segment models have been evaluated against a reference standard to establish kinematic accuracy. RESEARCH QUESTION: How accurately do skin-markers estimate foot and ankle motion for the modified Shriners Hospitals for Children Greenville (mSHCG) multi-segment foot model when compared against the reference standard, dual fluoroscopy (DF), during gait, in asymptomatic participants? METHODS: Five participants walked overground as full-body skin-marker trajectory data and DF images of the foot and shank were simultaneously acquired. Using the mSHCG model, ankle and midfoot angles were calculated throughout stance for both motion analysis techniques. Statistical parametric mapping assessed differences in joint angles and marker positions between skin-marker and DF motion analysis techniques. Paired t tests, and linear regression models were used to compare joint angles and range of motion (ROM) calculated from the two techniques. RESULTS: In the coronal plane, the skin-marker model significantly overestimated ROM (p = 0.028). Further, the DF model midfoot ROM was significantly positively related to differences between DF and skin-marker midfoot angles (p = 0.035, adjusted R2 = 0.76). In the sagittal plane, skin-markers underestimated ankle angles by as much as 7.26°, while midfoot angles were overestimated by as much as 9.01°. However, DF and skin-marker joint angles were not significantly different over stance. Skin-markers on the tibia, calcaneus, and fifth metatarsal had significantly different positions than the DF markers along the direction of walking for isolated portions that were less than 10 % of stance. Euclidean distances between DF and skin-markers positions were less than 9.36 mm. SIGNIFICANCE: As the accuracy of the mSHCG model was formerly unknown, the results of this study provide ranges of confidence for key angles calculated by this model.
Authors: Koren E Roach; Bibo Wang; Ashley L Kapron; Niccolo M Fiorentino; Charles L Saltzman; K Bo Foreman; Andrew E Anderson Journal: J Biomech Eng Date: 2016-09-01 Impact factor: 2.097
Authors: Sang Gyo Seo; Dong Yeon Lee; Hyuk Ju Moon; Sung Ju Kim; Jihyeung Kim; Kyoung Min Lee; Chin Youb Chung; In Ho Choi Journal: J Foot Ankle Res Date: 2014-04-22 Impact factor: 2.303