SLR - June 2015 - Steven Gillespie

Plantar Loading During Cutting While Wearing a Rigid Carbon Fiber Insert

Reference: Queen RM, Abbey AN, Verma R, Butler RJ, Nunley JA. Plantar loading during cutting while wearing a rigid carbon fiber insert. J Athl Train. 2014 May-Jun;49(3):297-303

Scientific Literature Review

Reviewed By: Steven Gillespie, DPM
Residency Program: Southern Arizona VA Health Care System

Podiatric Relevance: Fifth metatarsal stress fractures are a frequently seen overuse injury, especially in athletes. The authors examine if adding a rigid carbon fiber insert into an athletic shoe would decrease plantar loading forces during two agility moves.

Methods: Nineteen college-aged males were recruited without history of lower extremity injury in the past six months or foot surgeries within the last three years. Using an in-shoe pressure measurement system, plantar pressure data was collected as the subjects did two types of agility moves; side-cuts and crossover-cuts. All subjects performed both types of cutting moves in a randomized way to prevent fatigue. The use of carbon fiber inserts compared to shoes without the inserts was also randomized.

Result: The total foot peak pressure was increased in both side cut and crossover cuts by 54 percent and 60 percent respectively with the rigid carbon footplate. The total foot contact area was decreased with both cuts by 28 percent with the side-cut and 9.7 percent with the crossover-cut.

Conclusions: While wearing the shank, the lateral column of the foot experienced increased pressures and decreased contact area with cutting compared to wearing shoes without the shank. Their results show that wearing a carbon fiber insert would probably not be warranted for patients hoping to compete in agility sports while recovering from a fifth metatarsal stress fracture, as it could be detrimental to healing and ineffective in decreasing plantar loading beneath the lateral column of the foot.

Educational Opportunities