Alex Kountouris

Fast Bowlers in Cricket Demonstrate Up to 3- to 4-Week Delay Between High Workloads and Increased Risk of Injury

Background Limited research in cricket bowlers and baseball pitchers has shown a correlation between workload and injury risk. Hypothesis Acute high bowling workload in cricket leads to increased risk of bowling injury in future matches. Study Design Cohort study (prognosis); Level of evidence, 2. Methods One hundred twenty-nine pace (fast) bowlers who bowled in 2715 player matches over a period of 10 seasons were followed to compare overs bowled in each match and injury risk subsequent to the match. Results Bowlers who bowled more than 50 overs in a match had an injury incidence in the next 21 days of 3.37 injuries per 1000 overs bowled, a significantly increased risk compared with those bowlers who bowled less than 50 overs (relative risk [RR], 1.77; 95% confidence interval [CI]: 1.05–2.98). Bowlers who bowled more than 30 overs in the second inning of a match had a significantly increased injury risk per over bowled in the next 28 days (RR, 2.42; 95% CI: 1.38–4.26). Time periods of less than 21 days or more than 28 days after the match in question did not yield significant differences in injury risk per over bowled between high and low workload bowlers. Conclusion High acute workload in cricket fast bowlers may lead to a somewhat delayed increased risk of injury up to 3 to 4 weeks after the acute overload, possibly via a mechanism of damaging immature (repair) tissue. Clinical Relevance Cricket fast bowling and possibly baseball pitching workloads require scrutiny not just for acute injuries but also for injury prevention in the subsequent month.

Cricket fast bowling workload patterns as risk factors for tendon, muscle, bone and joint injuries

Objective To assess workload-related risk factors for injuries to particular tissue types in cricket fast bowlers. Design 235 fast bowlers who bowled in 14600 player innings over a period of 15 years were followed in a prospective cohort risk factor study to compare overs bowled in each match (including preceding workload patterns) and injury risk in the 3–4 weeks subsequent to the match. Injuries were categorised according to the affected tissue type as either: bone stress, tendon injuries, muscle strain or joint injuries. Workload risk factors were examined using binomial logistic regression multivariate analysis, with a forward stepwise procedure requiring a significance of <0.05. Results High acute match workload and high previous season workload were risk factors for tendon injuries, but high medium term (3-month workload) was protective. For bone stress injuries, high medium term workload and low career workload were risk factors. For joint injuries, high previous season and career workload were risk factors. There was little relationship between muscle injury and workload although high previous season workload was slightly protective. Conclusions The level of injury risk for some tissue types varies in response to preceding fast bowling workload, with tendon injuries most affected by workload patterns. Workload planning may need to be individualised, depending on individual susceptibility to various injury types. This study supports the theory that tendons are at lowest risk with consistent workloads and susceptible to injury with sudden upgrades in workload. Gradual upgrades are recommended, particularly at the start of a bowlers career to reduce the risk of bone stress injury.

Changes to injury profile (and recommended cricket injury definitions) based on the increased frequency of Twenty20 cricket matches

This study analyzes injuries occurring prospectively in Australian men’s cricket at the state and national levels over 11 seasons (concluding in season 2008–09). In the last four of these seasons, there was more cricket played, with most of the growth being a new form of the game – Twenty20 cricket. Since the introduction of a regular Twenty20 program, injury incidence rates in each form of cricket have been fairly steady. Because of the short match duration, Twenty20 cricket exhibits a high match injury incidence, expressed as injuries per 10,000 hours of play. Expressed as injuries per days of play, Twenty20 cricket injury rates compare more favorably to other forms of cricket. Domestic level Twenty20 cricket resulted in 145 injuries per 1000 days of play (compared to 219 injuries per 1000 days of domestic one day cricket, and 112 injuries per 1000 days of play in first class domestic cricket). It is therefore recommended that match injury incidence measures be expressed in units of injuries per 1000 days of play. Given the high numbers of injuries which are of gradual onset, seasonal injury incidence rates (which typically range from 15–20 injuries per team per defined ‘season’) are probably a superior incidence measure. Thigh and hamstring strains have become clearly the most common injury in the past two years (greater than four injuries per team per season), perhaps associated with the increased amount of Twenty20 cricket. Injury prevalence rates have risen in conjunction with an increase in the density of the cricket calendar. Annual injury prevalence rates (average proportion of players missing through injury) have exceeded 10% in the last three years, with the injury prevalence rates for fast bowlers exceeding 18%. As the amount of scheduled cricket is unlikely to be reduced in future years, teams may need to develop a squad rotation for fast bowlers, similar to pitching staff in baseball, to reduce the injury rates for fast bowlers. Consideration should be given to rule changes which may reduce the impact of injury. In particular, allowing the 12th man to play as a full substitute in first class cricket (and therefore take some of the bowling workload in the second innings) would probably reduce bowling injury prevalence in cricket.

The management of tennis elbow

#### Summary points Tennis elbow is a tendinopathy of the common extensor origin (fig 1⇓) of the lateral elbow. Although the pathology is in the elbow region, patients present with gradual onset of pain on extension movements of the wrist and fingers and supination of the forearm. The condition was formerly known as “lateral epicondylitis.” Because the pathology is no longer thought to be inflammatory, the “itis” suffix is a misnomer,1 2 and it is more accurately described as a partially reversible but degenerative overuse-underuse tendinopathy. Because of the length of this term, most clinicians prefer to use the informal name “tennis elbow.” The condition is usually easy to diagnose on clinical presentation (imaging is rarely needed to exclude coexisting elbow joint pathology) but much harder to cure. The clinical features are tenderness at the lateral epicondyle, normal elbow range of motion, and pain on resisted movements (particularly resisted third finger extension). If the elbow’s range of motion is restricted, other diagnoses should be considered because the loss of range suggests joint pathology. #### Sources and selection criteria We performed a search of PubMed and SPORTDiscus for the terms “tennis elbow” and “lateral epicondl*” and extracted what we thought were the most valid reviews and trials of …

Quadratus lumborum asymmetry and lumbar spine injury in cricket fast bowlers

OBJECTIVES Previous studies have demonstrated quadratus lumborum asymmetry in cricket fast bowlers, but there has been conflicting evidence regarding the relationship to lumbar spine injury, particularly vertebral bone stress injuries. This study investigated the relationship between quadratus lumborum asymmetry and lumbar spine injury in adolescent cricket fast bowlers. DESIGN The study was a prospective cohort design. METHODS Magnetic resonance imaging of 38 adolescent cricket fast bowlers was completed prior to a cricket season, and the cross sectional area of the quadratus lumborum muscle was measured at each lumbar spinal level. The bowlers were followed through the cricket season and those that reported lumbar spine injuries were investigated and classified as either having a soft tissue injury or a bone stress injury. The pre-season cross sectional area of quadratus lumborum was associated with injury status at the conclusion of the cricket season. RESULTS Twenty-one percent of the cohort developed lumbar bone stress injuries during the cricket season. There was no significant relationship between lumbar spine injury and quadratus lumborum cross sectional area. CONCLUSIONS A high incidence of lumbar bone stress injuries was demonstrated in adolescent fast bowlers. Unlike previous research that demonstrated a link between lumbar spine bone stress injuries and quadratus lumborum cross-sectional area, no such relationship was found.

International consensus statement on injury surveillance in cricket: a 2016 update

Cricket was the first sport to publish recommended methods for injury surveillance in 2005. Since then, there have been changes to the nature of both cricket and injury surveillance. Researchers representing the major cricket playing nations met to propose changes to the previous recommendations, with an agreed voting block of 14. It was decided that 10 of 14 votes (70%) were required to add a new definition element and 11 of 14 (80%) were required to amend a previous definition. In addition to the previously agreed ‘Match time-loss’ injury, definitions of ‘General time-loss’, ‘Medical presentation’, ‘Player-reported’ and ‘Imaging-abnormality’ injuries are now provided. Further, new injury incidence units of match injuries per 1000 player days, and annual injuries per 100 players per year are recommended. There was a shift towards recommending a greater number of possible definitions, due to differing contexts and foci of cricket research (eg, professional vs amateur; injury surveillance systems vs specific injury category studies). It is recommended that researchers use and report as many of the definitions as possible to assist both comparisons between studies within cricket and with those from other sports.

Fast bowling match workloads over 5-26 days and risk of injury in the following month

OBJECTIVES This study examined whether high match fast bowling workloads in the short to medium term were associated with increased bowling injury rates. DESIGN Prospective cohort study. METHODS Over a 15 year period, workload patterns for 235 individual fast bowlers during time periods from 5 to 26 days were examined to consider whether there was an increased injury rate during the month (28 days) subsequent to the workload. RESULTS Fast bowlers who bowled more than 50 match overs in a 5 day period had a significant increase in injury over the next month compared to bowlers who bowled 50 overs or less RR 1.54 (95% CI 1.04-2.29). For periods ranging from 12 to 26 days, there was no statistically-significant increase in injury over the next month from exceeding thresholds of certain amounts of overs, although bowlers who bowled more than 100 overs in 17 days had a non-significant increase in injury over the next month RR 1.78 (95% CI 0.90-3.50). CONCLUSION There were no statistically-significant increases in subsequent injury risk for high workloads for periods of 12-26 days, although exceeding 100 overs in 17 days (or less) was associated with higher injury rates. Compression of cricket fixtures is likely to have only a minimal contribution to increased fast bowling injury rates being seen in the T20 era (along with sudden workload increases due to transferring between forms of the game, which has been previously established as a major contributor).

Cricket fast bowlers without low back pain have larger quadratus lumborum asymmetry than injured bowlers.

Objective:The objective of the study was to determine the magnitude and side of quadratus lumborum (QL) asymmetries in elite, adult, cricket fast bowlers and the relationship with lumbar spine injury. Design:Cohort study. Setting:Cricket fast bowers had magnetic resonance (MR) scans at the start of a cricket season and their injury characteristics over the next cricket season were compared with the amount of QL asymmetry. Participants:Twenty-three elite, asymptomatic, adult, cricket fast bowlers. Assessment of Risk Factors:The cross-sectional area (CSA) of QL was measured using MR imaging. The association between side-to-side differences in CSA (asymmetry) was evaluated as a possible risk factor for development of lumbar spine injury. Main Outcome Measures:The main outcome measurements were QL CSA and asymmetry in relation to lumbar spine injury in cricket fast bowlers. Results:There were a greater proportion of dominant- (bowling arm) side asymmetries (65%). Asymmetry magnitudes that favored the dominant side were not significantly larger than those on the nondominant side. Four participants who had bone oedema on MR imaging preseason went on to develop symptomatic lumbar stress fractures. Participants with no lumbar spine injury had significantly larger QL asymmetries than those who sustained lumbar spine injury. Conclusions:Cricket fast bowlers demonstrated asymmetrical QL development, which may be related to the trunk positions adopted in the fast bowling technique. Uninjured bowlers had larger asymmetries than those who developed lumbar spine injury, which is contrary to some previous research.

Pace bowlers in cricket with history of lumbar stress fracture have increased risk of lower limb muscle strains, particularly calf strains.

Objective To assess whether a history of lumbar stress fracture in pace bowlers in cricket is a risk factor for lower limb muscle strains. Methods This was a prospective cohort risk factor study, conducted using injury data from contracted first class pace bowlers in Australia during seasons 1998–1999 to 2008–2009 inclusive. There were 205 pace bowlers, 33 of whom suffered a lumbar stress fracture when playing first class cricket. Risk ratios ([RR] with 95% confidence intervals[CI]) were calculated to compare the seasonal incidence of various injuries between bowlers with a prior history of lumbar stress fracture and those with no history of lumbar stress fracture. Results Risk of calf strain was strongly associated with prior lumbar stress fracture injury history (RR = 4.1; 95% CI: 2.4–7.1). Risks of both hamstring strain (RR = 1.5; 95% CI: 1.03–2.1) and quadriceps strain (RR = 2.0; 95% CI: 1.1–3.5) were somewhat associated with history of lumbar stress fracture. Risk of groin strain was not associated with history of lumbar stress fracture (RR = 0.7; 95% CI: 0.4–1.1). Other injuries showed little association with prior lumbar stress fracture, although knee cartilage injuries were more likely in the non-stress fracture group. Conclusion Bony hypertrophy associated with lumbar stress fracture healing may lead to subsequent lumbar nerve root impingement, making lower limb muscle strains more likely to occur. Confounders may be responsible for some of the findings. In particular, bowling speed is likely to be independently correlated with risk of lumbar stress fracture and risk of muscle strain. However, as the relationship between lumbar stress fracture history and calf strain was very strong, and that there is a strong theoretical basis for the connection, it is likely that this is a true association.

Incidence and prevalence of elite male cricket injuries using updated consensus definitions

Background T20 (Twenty20 or 20 over) cricket has emerged in the last decade as the most popular form of cricket (in terms of spectator attendances). International consensus cricket definitions, first published in 2005, were updated in 2016 to better reflect the rise to prominence of T20 cricket. Methods Injury incidence and prevalence rates were calculated using the new international methods and units for elite senior male Australian cricketers over the past decade (season 2006–2007 to season 2015–2016 inclusive). Results Over the past 10 seasons, average match injury incidence, for match time-loss injuries, was 155 injuries/1,000 days of play, with the highest daily rates in 50-over cricket, followed by 20-over cricket and First-Class matches. Annual injury incidence was 64 injuries/100 players per season, and average annual injury prevalence was 12.5% (although fast bowlers averaged 20.6%, much higher than other positions). The most common injury was the hamstring strain (seasonal incidence 8.7 injuries/100 players per season). The most prevalent injury was lumbar stress fractures (1.9% of players unavailable at all times owing to these injuries, which represents 15% of all missed playing time). Discussion The hamstring strain has emerged from being one of the many common injuries in elite cricket a decade ago to being clearly the most common injury in the sport at the elite level. This is presumably in association with increased T20 cricket. Lumbar stress fractures in fast bowlers are still the most prevalent injury in the sport of cricket at the elite level, although these injuries are more associated with high workloads arising from the longer forms of the game. Domestic and international matches have very similar match injury incidence rates across the formats, but injury prevalence is higher in international players as they play for most of the year without a substantial off-season.