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ORIGINAL ARTICLE
Incidence of injury in semi-professional rugby league players T J Gabbett .............................................................................................................................
Br J Sports Med 2003;37:36–44
Objectives: To investigate the site, nature, cause, and severity of injuries in semi-professional rugby league players. Methods: The incidence of injury was prospectively studied in one hundred and fifty six semi-professional rugby league players over two competitive seasons. All injuries sustained during matches and training sessions were recorded. Injury data were collected from a total of 137 matches and 148 training sessions. Information recorded included the date and time of injury, site, nature, cause, and severity of injury. Results: During the two seasons, 1694 playing injuries and 559 training injuries were sustained. The match injury incidence was 824.7 per 1000 player-position game hours and training injury incidence was 45.3 per 1000 training hours. Over 20% of the total training (17.4 per 1000) and playing (168.0 per 1000) injuries sustained were to the thigh and calf. Muscular injuries (haematomas and strains) were the most common type of injury sustained during training (22.0 per 1000, 48.7%) and matches (271.7 per 1000, 32.9%). Playing injuries were most commonly sustained in tackles (382.2 per 1000, . . . . . . . . . . . . . . . . . . . . . . . 46.3%), while overexertion was the most common cause of training injuries (15.5 per 1000, 34.4%). Correspondence to: The majority of playing injuries were sustained in the first half of matches (1013.6 per 1000, 61.5% T Gabbett, Queensland v 635.8 per 1000, 38.5%), whereas training injuries occurred more frequently in the latter stages of Academy of Sport, PO Box the training session (50.0 per 1000, 55.3% v 40.5 per 1000, 44.7%). Significantly more training 8103, Wooloongabba, injuries were sustained in the early half of the season, however, playing injuries occurred more Queensland 4102, Australia; frequently in the latter stages of the season.
[email protected] Conclusions: These results suggest that changes in training and playing intensity impact significantly upon injury rates in semi-professional rugby league players. Further studies investigating the influence Accepted 17 April 2002 . . . . . . . . . . . . . . . . . . . . . . . of training and playing intensity on injuries in rugby league are warranted.
R
ugby league is an international collision sport played at amateur,1 2 semi-professional,3 and professional4 levels. The game is physically demanding requiring players to compete in a challenging contest involving frequent bouts of high intensity activity, such as, running, passing, sprinting, separated by short bouts of low intensity activity, such as walking, jogging.5 During the course of a match players are exposed to numerous physical collisions and tackles.6 As a result, musculoskeletal injuries are common.7 Several studies have documented the incidence of injury in amateur2 8 and professional9–11 rugby league, with professional players having 1.3–2.2-fold higher injury rates than amateur players. Not surprisingly, both amateur and professional rugby league injury studies have identified the tackle to be the most common cause of injury.2 9 11 12 While no significant differences have been reported between first and second half injuries for professional players,13 the majority (70.8%) of amateur rugby league injuries occur in the second half of matches, suggesting that fatigue, or a fatigue induced reduction in skill contributes to injuries in these athletes.8 Recent evidence has shown a progressive improvement in the physiological capacities of rugby league players as the playing level is increased.14 Semi-professional players have inferior muscular power, speed, and maximal aerobic power to professional players4 15 but superior physiological capacities to amateur players.16 The higher physiological capacities of semiprofessional players in comparison to amateur players may suggest a lower susceptibility to fatigue related injuries. However, given the progressive improvement in physiological capacities14 and that injury rates are increased with higher playing intensity,9 11 17 one might also expect a progressive rise in the injury rates of amateur, semi-professional, and
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professional rugby league players. While the incidence of amateur and professional rugby league injuries has been documented, no study has investigated the incidence of injury in semi-professional rugby league players. With this in mind, the purpose of the present investigation was to document the incidence of injury in semi-professional rugby league players over two consecutive seasons.
METHODS The incidence, site, nature, cause, and severity of training and playing injuries was prospectively studied in 156 semiprofessional rugby league players over two consecutive seasons (2000 and 2001). The total number of registered players over this period was 77 and 79, respectively, with 39 players competing in both seasons. Each season lasted from December– September, with matches played from January–September. All players were registered with the same rugby league club, and were competing in the Gold Coast Group 18 semi-professional senior rugby league competition (New South Wales Country Rugby League, Australia). The New South Wales Country Rugby League governs competitions of a standard below the National Rugby League professional competition and the New South Wales Rugby League semi-professional competitions—for example, First Division, Metropolitan Cup, Jersey Flegg, SG Ball, and Matthews Cup—but above Second Division and amateur level competitions. Players were defined as “semi-professional” as they were receiving moderate remuneration to play rugby league, but were also relying on additional employment to generate income. The definition of a semi-professional player distinguished the subjects of the present study from amateur players, (who do not receive match payments), and professional
Semi-professional rugby league injuries
Name:
Initials:
Team: Date of Injury
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Grade: /
/
Type of activity at time of injury training/practice competition other Reason for Presentation new injury exacerbated/aggravated injury recurrent injury illness other Body Region Injured Tick or circle body part/s injured & name
Position: DOB:
Circle /
/
Nature of Injury/Illness abrasion/graze sprain eg ligament tear strain eg muscle tear open wound/laceration/cut bruise/contusion inflammation/swelling fracture (including suspected) dislocation/subluxation overuse injury to muscle or tendon blisters concussion cardiac problem respiratory problem loss of consciousness unspecified medical condition other
Gender: M
F
Player/Referee/Coach/Spectator
Venue/area at which injury occurred:
Explain exactly how the incident occurred
Were there any contributing factors to the incident, unsuitable footwear, playing surface, equipment, foul play?
Advice Given immediate return unrestricted activity able to return with restriction unable to return at present time Referral no referral medical practitioner physiotherapist chiropractor or other professional ambulance transport hospital other Provisional severity assessment mild (1–7 days modified activity) moderate (8–21 days modified activity) severe (>21 days modified or lost)
Provisional diagnosis/es Protective Equipment Was protective equipment worn on the injured body part? yes no CAUSE OF INJURY
Body part/s
Mechanism of Injury struck by other player (eg in tackle) struck by ball (eg dislocated finger) collision with or tackling other player collision with fixed object (goal post) fall/stumble on same level slip/trip twisting to pass or accelerate scrum collapse or scrum contact overexertion (eg muscle tear) overuse temperature related eg heat stress other
If yes, what type eg mouthguard, ankle brace, taping.
Treating person medical practitioner physiotherapist nurse sports trainer other Signature of treating person
Initial Treatment none given (not required) dressing RICER crutches sling, splint manual therapy massage stretch/exercises CPR strapping/taping only none given – referred elsewhere other
Today's Date:
/
/
Figure 1 Injury reporting form.18
players (who generate their entire income from their involvement in rugby league).2 The playing roster for each season included 57 players, with the remaining players relegated to the amateur team affiliated with the club. Depending on age and skill levels, players competed in one of three teams (First Grade, Second Grade, or Under 19). Second Grade and Under 19 teams consisted of a squad of twenty players while the First Grade team consisted of a squad of seventeen players. Over the two competitive seasons, all injuries sustained to the total cohort of 156 players were recorded. Injury data were collected from 137 matches, which included all trial, fixture, and finals matches. All trial matches were 60 minutes in duration. Fixture and finals matches were either 60 minutes (Under 19), 70 minutes (Second Grade), or 80 minutes (First Grade) in duration. One finals match (Second Grade) required 2 × 10 minute “extra-time” periods (90 minutes in duration) due to level scores at the completion of regulation time. In addition, each player participated in two organised field training sessions per week, with each training session lasting approximately 90 minutes in duration. Injury data were collected from a total of 148 training sessions, which included all preseason and in season training sessions that corresponded with preseason, fixture, and finals matches. All Under 19 players participated in 138 training sessions, which corresponded with preseason, fixture, and finals matches. All First Grade and Reserve Grade players participated in 148 training sessions, which corresponded with preseason, fixture, and finals matches. Definition of injury A single head trainer, employed by the club to provide injury prevention and management services, and skills and conditioning coaching, assessed all injuries. The head trainer held tertiary qualifications in exercise and sport science and was
nationally accredited in injury prevention, assessment, and management. For the purpose of this study, an injury was defined as any pain or disability suffered by a player during a match or training session, and subsequently assessed by the head trainer during, or immediately following the match or training session.3 8 All injuries sustained during matches and training sessions were recorded using a standardised injury reporting form (fig 1).18 Where necessary, slight modifications were made to the injury reporting form to allow for potential differences in the cause of injury between matches and training sessions. To allow comparison among other studies,10 17 injuries were also classified according to the number of matches missed as a result of the injury. Injuries were classified as transient (no matches missed), minor (one match missed), moderate (two to four matches missed), and major (five or more matches missed).17 Classification of injury Injuries were categorised according to the site of injury.3 8 The head and neck, face, abdomen and thorax, shoulder, arm and hand, thigh and calf, knee, ankle and foot, and “others” categories were the sites selected. Injuries were also described according to the type (nature) of injury sustained.3 8 Muscular injuries were classified as either haematomas or muscular strains. Additional categories for the type of injury included joint injuries, concussions, contusions, abrasions, blisters, lacerations, fractures and dislocations, respiratory disorders, unspecified medical conditions, and “others”. Finally, injuries were described according to the cause of injury.2 9 Causes of injury were categorised as being tackled, while tackling, being struck by another player or ball, collision with another player or fixed object (for example, goal post, ground), fall/stumble, slip/trip, twisting to pass or accelerate, scrum contact, overexertion, overuse, temperature related disorders (for example, heat stress), and “others”.
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Gabbett
Table 1 Observed and expected training and match injury frequency Playing
Expected Observed
Training
2000
2001
2000
2001
842 746
852 948
264 170
295 389
STATISTICS Injury rates were calculated as described previously.17 Over the two competitive seasons, 137 matches were played. Fifty four matches lasted 60 minutes, 41 matches lasted 70 minutes, and 41 matches lasted 80 minutes in duration. One match lasted 90 minutes in duration. Therefore, the average duration of matches was 1.1533 hours. Match injury exposure was calculated by multiplying the number of players, the match duration, and the number of matches. The overall match injury exposure for all players was 2054 playing hours at risk (13 players × 1.1533 hours × 137 matches). Training injury exposure was calculated by multiplying the number of players, the number of training weeks, the session duration, and the number of sessions per week.10 The overall training injury exposure for all players was 12 354 training hours at risk (57 players × 69 weeks × 1.5 hours/session × 2 sessions/week) + (37 players × 5 weeks × 1.5 hours/session × 2 sessions/week). Expected injury rates were calculated as described by Hodgson Phillips et al.10 The χ2 test was used to determine whether the observed injury frequency was significantly different from the expected injury frequency (table 1). The level of significance was set at p
