The epidemiology, clinical characteristics and associated risk factors for injury among football players at an academy in Ghana

Abstract

Background: Football is arguably the most common team sport in the world, with a resultant and rapid increase in the formation of young football academies, including Ghana. However, football is significantly associated with a risk of injury. Efforts are being focused on younger populations to reduce injuries through improving understanding of epidemiology and injury prevention strategies. Sparse knowledge on injuries and their risk factors specific to academy football players in Ghana is available. Aim of the study: To determine the epidemiology, clinical characteristics and risk factors of football injuries, among players at a football academy in Ghana. Design: Observational prospective cohort study. Setting: A football academy in the Volta Region of Ghana. Participants: Fifty-three young (under 18 years) and 27 adult (18 years and above) football players. Methods: Eighty male, young and adult academy football players were recruited at a football academy in Ghana using total population sampling. Baseline measurements taken before the start of the football season included height using a stadiometer (Seca 213), weight using a digital scale (Omron HN-289), and ankle dorsiflexion (DF) range of motion (ROM) were measured with a tape measure. Functional ankle instability was measured with the Star Excursion Balance Test (SEBT) and the Cumberland Ankle Instability Tool (CAIT). A standardised injury surveillance form (SIS) developed by the International Olympic Committee (IOC), was used by two qualified senior physiotherapists to prospectively document players’ injuries and injury characteristics during one season. The first author visited the study site once a month to ensure` validity of data captured to extract data from physiotherapists’ files. All data collected were entered into a Microsoft Excel spreadsheet for analysis according to the International Olympic Committee (IOC) reporting guidelines. In addition to descriptive statistics, selected variables associated with football injuries were statistically investigated using Spearman’s rank correlation with interpretation at a significance level of 5%. Results: A total of 126 injuries were reported during the assessed football season, with 66% and 60% occurring during matches and training, respectively. The average weekly injury prevalence was 4.1%, and overall injury incidence was 4.5 injuries per 1 000 hours. Match incidence (27.4 per 1 000 hours) was higher than training incidence (2.3 per 1 000 hours). The U14, U16 and U18 players suffered higher injury incidence (5.8, 5.1, 5.7 injuries per 1 000 hours respectively) compared to senior players (2.7 per 1 000 hours). A total of 109 injuries (86.5%) affected the lower limb, with the knee (n=30, 23.8%) being the most affected, followed by the ankle and the hip/groin (both n=17, 13.5%), and 57 (45.2%) injuries were due to acute trauma, occurring with direct contact with another player (n=42, 33.3%). The most common injury areas were joint sprains (n=54, 43.9%), followed by muscle strains (n=33, 26.2%), and bone contusions (n=11, 8.7%). The severity of injuries was mostly moderate (n=56, 44.4%). New injuries (n=112, 88.9%) occurred more commonly during matches than during training (n=59. 46.8% vs n=53, 42.1%). Of the total recorded number of recurrent injuries (n=14, 11.1%), most occurred among the U18 players (n=10, 17.2%). The following risk factors were associated with overall-, match- or training injury incidence during the season: Age was negatively associated with overall injury incidence (r=-0.589, p=0.000), and training injury incidence (r=-0.314, p=0.005). A record of previous injury among U18 players was associated with training injury incidence (r= 0.436, p=0.023). The Body Mass Index (BMI) was negatively associated with overall injury incidence (r=-0.513, p=0.000) and training injury incidence (r=- 0.395, p=0.000). However, only for U18 players the BMI was negatively associated with overall injury incidence (r=- 0.428, p=0.021), based on age category. CAIT scores (for ankle instability) were positively associated with overall (n=0.263, p=0.019) and match injury incidence (r=0.263, p=0.029) whilst only senior players’ range of motion (ROM) of the left ankle (dorsiflexion) was positively associated with training injury incidence (r=0.436, p=0.023). Player position was associated with match injury incidence (r=0.241, p=0.031) while the attacker position among U16 was associated with training injury incidence (r=0.669, p=0.003). Conclusion: Injury incidence over a competitive season was higher among younger players, compared to senior players. The majority of training injuries occurred in non-contact scenarios, whereas contact injuries were more common during matches. Most reported injuries were joint sprains and muscle strains, which mostly affected the lower limb. A younger age, lower BMI and higher self-reported functional ankle instability were risk factors associated with overall injury incidence of the whole population. In U18 players, a lower BMI and a previous injury were risk factors associated with increased injury incidence. Adult players’ ankle dorsiflexion ROM was associated with injury incidence. The ‘Attacker’ playing position was associated with an increased injury incidence among U16 players. This study's findings contribute to the collective understanding of injuries and risk injury factors among academy football players. These results can guide the development of future injury prevention strategies, specifically in Ghana. Further studies should focus on examining risk factors for specific anatomical locations, especially the ankle and the knee as well as specific injury types.