In professional football a key factor regarding injury is the time to return to play. Accurate prediction of this would aid planning by the club in the event of injury. It would also aid the club medical staff. Gaussian processes may be used for machine learning tasks such as regression and classification. This study determines whether machine-learning methods may be used for predicting how many days a player is unavailable to play.

A database of injuries at one English Premier League Professional Football Club was reviewed for a number of factors for each injury. Twenty-five variables were recorded for each injury, including time to return to play. This was determined to be the response variable. We used a Gaussian process model with a Laplacian kernel to determine whether the return to play could be predicted from the other variables.

The root mean square error was 13.186 days (S.D.: 8.073), the mean absolute error was 8.192 days (S.D.:13.106) and the mean relative error 171.97% (S.D.:75.56%). A linear trend was observed and the model demonstrated high accuracy with greater errors being observed for cases where the value of the response variable was higher, i.e. in those cases where the time to return to play was lengthy.

This is the first step in attempting to design a computer-based model that will accurately predict the time for a professional footballer to return to play. The model is extremely accurate for most cases, with errors increasing as the severity of the case increases too.

Introduction

Patella tendonitis is common amongst sportsmen. No published evidence of this injury in elite professional footballers exists. The aim of this study was to determine the frequency of this injury in the elite professional footballer, along with the impact of such an injury on the amount of time missed and the outcomes of various treatment options.

Introduction

Knee injuries are common amongst footballers. The aim of this study was to establish frequency and variation of knee injuries within one English Premier League (EPL) professional football club over two seasons, to assess number of days missed due to injury, and analyse current treatment regimen for each injury type.

Introduction

Foot and ankle injuries are a common occurrence amongst all footballers. The aim of this study was to establish the frequency and variation of foot and ankle injuries within one English Premier League (EPL) professional football club over the course of a season and attempt to identify any factors associated with the injuries.

Objective

Shoulder instability is a common cause of morbidity amongst Professional Rugby Union players. This study explores whether the risk of shoulder dislocation is associated with innate shoulder laxity.

Background: Foot injuries represent a small but important proportion of injuries to professional rugby union players. There are no detailed epidemiological studies regarding these injuries.

Purpose: The aim of this study was to describe the epidemiology of foot injuries sustained by a cohort of professional rugby union players and identify areas that may be targeted for injury prevention in the future.

Study design: Descriptive epidemiological study.

Methods: Medical personnel prospectively recorded injuries in professional, premiership rugby union players in England over 4 seasons. Injuries to the foot were identified and the time away from training and playing was reported.

Results: A total of 147-foot injuries were sustained resulting in 3,542 days of absence in total. Acute events accounted for 73% of all foot injuries, with chronic, mostly overuse conditions, accounting for 25% (undiagnosed 2%). Chronic conditions led to proportionately more time away from training and playing (p< 0.001). Specifically, stress fractures in the foot accounted for 8% of the total foot injuries but 22% of the absence. Navicular stress fractures had the longest recovery time with the mean return to training and match play of 188 days.

Conclusions: In collision sports, such as rugby, injury is inevitable, but clinicians should always be seeking ways to minimise their occurrence and impact. This study revealed significant morbidity associated with chronic and overuse foot injuries in these professional athletes. With greater attention paid to risk factors, some of these injuries, and importantly, recurrent injuries may be avoided.

Shoulder instability is a common cause of morbidity amongst Professional Rugby Union players. This study explores whether the risk of shoulder dislocation is associated with innate shoulder laxity. A prospective, randomised controlled study was completed in which all the Premiership Rugby Clubs in England were visited. 169 professional rugby players with no history of instability in either shoulder and 46 players with one shoulder with clinical instability symptoms were assessed. Shoulder laxity was measured by clinical evaluation, questionnaires and ultrasound. Anterior, posterior and inferior translation was measured in both shoulders for healthy players and the uninjured shoulder only for injured players. The results showed there was no significant difference between the left (anterior: mean 2.92 +/− 1.15 mm; posterior: mean 5.10 +/− 1.75 mm; inferior: mean 3.08 +/− 1.00 mm) and right (anterior: mean 3.07 +/− 1.14 mm; posterior: mean 4.87 +/− 1.61 mm; inferior: mean 2.91 +/− 0.99 mm) shoulders in healthy players (P > 0.05). The comparison between healthy shoulders (anterior: mean 3.00 +/− 1.15 mm; posterior: mean 4.99 +/− 1.68 mm; inferior: mean 3.00 +/− 1.00 mm) from healthy players and the uninjured shoulder (anterior: mean 4.16 +/− 1.70 mm; posterior: mean 6.16 +/− 3.04 mm; inferior: mean 3.42 +/− 1.18 mm) from injured players identified that players with unstable shoulders have a significantly higher shoulder translation in their normal shoulder than healthy players (P < 0.05). This is the first study looking at laxity and the risk of shoulder dislocations in sportsmen involved in a high contact sport. These results support the hypothesis that rugby players with “lax” shoulders are more likely to sustain a dislocation or subluxation injury to one of these lax shoulders in their sport.