Pathogenesis of Fifth Metatarsal Fractures in College Soccer Players

SLR - January 2016 - JennaLou Hollnagel

Podiatric Relevance: Fifth metatarsal stress fractures are a common finding in podiatric practice. The etiology of the fractures is still under investigation. Evaluating physical characteristics and environmental factors involved with fifth metatarsal stress fractures has received little attention. This article provides insight to possible physical and environmental characteristics a podiatrist should look out for when dealing with fifth metatarsal stress fractures, and athletes who could be at higher risk. Allowing the possibility of preventative medicine to help decrease the incidence of fifth metatarsal stress fractures.  

Methods: Case control study on the existence and correlation of fifth metatarsal stress fractures in 273 collegiate soccer players on the same team, utilizing the method of medical examination and survey between 2005-2013. During April of each fiscal year, a medical examination was performed and a survey was distributed. The survey assessed the history of foot or ankle injuries, dominant leg and footwear, while the medical examination assessed body demographics, foot-arch height ratio, toe-grip strength, quadriceps angle, leg-heel angle, functional reach test, single-leg standing time with eyes closed, straight-leg raising ankle, finger-floor distance, heel-buttock distance, ankle joint range of motion and general joint laxity. For those athletes who incurred a fifth metatarsal fracture an additional survey was used to assess an orthopedic physical examination, studs in footwear and playing surface. Athletes were then divided into injury and non-injury group. The injury group was further divided into dominant vs non-dominant leg. The incidence of fifth metatarsal stress fractures was calculated for each group, and comparisons were conducted.

Results: Of the 273 athletes, only 16 comprised the injury group. There was a significant difference in the toe-grip strength, dominance of leg and Q angle. All other characteristics and environmental factors were not significantly different. In the injury group the toe-grip strength was significantly weaker (1.21, 95 percent CI) and the Q angle was lower (1.27, 95 percent CI) than the non-injury group. In addition the frequency of fifth metatarsal stress fractures was more prevalent in the non-dominant leg.

Conclusions: It is suggested that athletes who have sustained a fifth metatarsal stress fracture had significantly weaker toe-grip strength. Along with a logistic regression analysis suggesting that toe-grip strength is associated with fifth metatarsal stress fractures. There was also a significantly higher frequency of the fracture occurring in the non-dominant leg. The Q angle was also lower in athletes with fifth metatarsal stress fractures but the values were still within normal limits, requiring further evaluation. With this knowledge of persons to be at a higher risk of obtaining a fifth metatarsal fracture, this will further help provide treatment and prevention plans for the patients.