<![CDATA[Journal of Orthopaedic & Sports Physical Therapy - Ian R. Byram, BA]]> http://www.jospt.org/ianrbyram Wed, 30 Apr 2008 09:05:25 EST 0 Effects of Wearing Foot Orthosis With Medial Arch Support on the Fifth Metatarsal Loading and Ankle Inversion Angle in Selected Basketball Tasks http://www.jospt.org/issues/articleID.1246/article_detail.asp Michael T. Gross, Bing Yu, Jennifer J. Preston, Robin M. Queen, Ian R. Byram, W. Mack Hardaker, J. Marc Davis, Timothy N. Taft, William E. Garrett
STUDY DESIGN: Preintervention and postintervention, repeated-measures experimental design. OBJECTIVES: The objective was to investigate the effects of foot orthoses with medial arch sup­port on ankle inversion angle and plantar forces and pressures on the fifth metatarsal during land­ing for a basketball lay-up and during the stance phase of a shuttle run. BACKGROUND: Proximal fractures of the fifth metatarsal, specifically the Jones fracture, are common in sports. Wearing foot orthoses with medial arch support could increase the ankle in­version angle and the plantar forces and pressure on the fifth metatarsal that may increase the risk for fifth metatarsal fracture. METHODS AND MEASURES: Three-dimen­sional (3-D) videographic, force plate, and in-shoe plantar force and pressure data were collected during landing after a basketball lay-up and during the stance phase of a shuttle run with and without foot orthoses with medial arch support for 14 male subjects. Two-way ANOVAs with repeated mea­sures were performed to compare ankle inversion angle, maximum forces, and pressure on the fifth metatarsal head and base between conditions and between tasks. RESULTS: The maximum ankle inversion angle and maximum plantar force and pressure on the base of the fifth metatarsal during both tasks as well as the maximum plantar force and pressure on the head of the fifth metatarsal during the stance of the shuttle run were significantly increased (P<.026) when wearing foot orthoses. No significant differences were found in the maxi­mum vertical ground reaction forces between foot orthotic conditions. CONCLUSION: Generic use of off-the-shelf foot orthoses with medial arch support causes increased plantar forces and pressures on the fifth metatarsal and may increase the risk for proximal fracture of the fifth metatarsal. Future studies are needed to investigate this risk, acknowledging that the differences noted in our study were small in magnitude and the foot type was not measured.

 

J Orthop Sports Phys Ther. 2007;37(4):186-191. doi:10.2519/jospt.2007.2327

 

KEY WORDS: fifth metatarsal fractures, foot orthoses, in-shoe pressure, Jones fracture]]> http://www.jospt.org/issues/articleID.1246/article_detail.asp