Intrinsic risk factors for lower limb injuries in university-level female soccer players

Abstract

The game of soccer or football is known for its competitive nature, complex movement patterns and high intensity. There are frequent lower limb injuries because of the high demands of the game and the complex movement patterns that the game requires. This intensity and complexity of movements furthermore result in a variety of intrinsic factors that contribute to the occurrence of lower limb injuries. The first objective of the study was to determine the injury prevalence among university-level female soccer players. This was determined through the completion of an injury history questionnaire that was used to profile the nature of injuries sustained in the past six months in preparation for the 2016 University Sports South Africa (USSA) National Football Championships. The second objective was to determine the intrinsic risk factors associated with lower limb injuries in university-level female soccer players. Measurements of ankle dorsiflexion, plantarflexion, inversion and eversion ROM, the flexibility of both quadriceps and hamstrings, quadriceps-angle (Q-angle) and lower limb stability on the Biodex Stability System was used to determine this. Fifty-three female soccer players (aged 18 to 25 years) from North-West University and Tshwane University of Technology voluntarily participated in the study during preparation for the 2016 USSA National Football Championships. The results for the first objective indicated the significant prevalence of sport injuries according to the number of injuries that were reported (p<0,0001). The most vulnerable anatomical sites of injury were the ankle (28,6%) and knee (22,2%) (p<0,001). While all playing positions were vulnerable to injuries, the most vulnerable were the defenders, goalkeepers and strikers (p<0,05). The second objective’s results indicated that the intrinsic risk factors significantly associated with lower limb injuries were decreased flexibility of ankle dorsiflexors (p<0,071) and lower limb stability medial lateral index (p<0,001). A strong correlation was also found between ankle invertors and injured players (r=0,251). The age, body mass, stature, body mass index (BMI), ankle eversion ankle plantarflexion ROM, hamstring and rectus femoris flexibility and Q-angle were not associated with an increased risk of lower limb injuries (p>0,05). The study concludes that the majority of soccer injuries occurred in the lower extremities with the ankle and knee as the most vulnerable anatomical sites. Moreover, decreased flexibility in the dorsiflexors, ankle invertors and lower limb stability are intrinsic risk factors that predisposed players to lower limb injuries. With the high prevalence of knee and ankle injuries in female players, more focus should be placed on preventing and reducing the incidence of such injuries. It is therefore recommended that neuromuscular and flexibility exercises be incorporated into training programmes to improve the neuromuscular function of the invertors and dorsiflexors and lower limb stability and thereby preventing lower limb injuries.