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Disc degeneration and the young fast bowler in cricket
Abstract
Twenty-four male fast bowlers of mean age 13.7 years, who bowled competitively at a school and club level were selected from five Western Australian schools. At the time of the testing all bowlers, who were bowling completely freely, underwent magnetic resonance imaging to detect the presence of intervertebral disc abnormalities. While these radiological data were being analysed, the players were filmed both laterally (200 Hz) and from directly above (100 Hz) as their front foot impacted a force platform during the delivery stride of the fast bowling action. In addition these bowlers performed selected physical capacity tests. The occurrence of abnormal radiological data were then used to group the bowlers (group 1, no abnormal features; group 2, disc degeneration and/or bulging on scan). A Mann-Whitney U rank test was then used to identify any significant differences (P < 0.1) between the groups for all dependent variables. Five of the subjects recorded abnormal magnetic resonance imaging scans of the lumbar spine, while nineteen recorded normal intervertebral discs, normal alignment of the lumbar spine, and no sign of spondylolisthesis. Bowlers who rotated the trunk to realign the shoulders to a more side-on position between back foot impact and front foot impact in the delivery stride were more likely to record abnormal intervertebral disc features.
... To classify the bowling action researchers have used different threshold criteria (Table 1.2). An early convention system introduced by Elliott, Davis, Khangure, Hardcastle, and Foster (1993a) included shoulder alignment, back foot angle and shoulder counter rotation. ...
... Later a similar convention system was proposed by Burnett, Elliott, and Marshall (1995) without the back foot angle criterion, but this system included the new parameters of shoulder alignment, pelvis shoulder separation angle and shoulder counter rotation. Portus et al.(2000) used similar criteria to Elliott et al. (1993a) in their first study, but slightly changed the threshold criteria of back foot angle and shoulder counter rotation. In their next study Portus et al. (2004) included shoulder alignment, pelvis shoulder separation angle and shoulder counter rotation, but excluded back foot angle criteria (see Table 1.2). ...
... while the three older studies reported only 2D biomechanical data Elliott et al., 1993a;Elliott et al., 1992). All but one of the six articles included male participants only (Bayne et al., 2016;Burnett et al., 1996;Elliott et al., 1993a;Elliott et al., 1992;Portus et al., 2004), while only a single study investigated female participants . ...
Injury prevalence rates of cricket fast bowlers increase over time. Fast bowlers lose 16% of potential playing time due to injury, while all other playing positions in cricket lose 5% of potential playing time. Most of the injuries of cricket fast bowlers occur in the lumbar region of the spine. Young fast bowlers have a higher risk of injury to the lower back compared to adult cricket fast bowlers and 37% - 55% of injuries among junior fast bowlers are in the lower back. Hence, the first aim of this thesis is to examine biomechanical factors associated with low back pain and injury in fast bowlers through a systematic review of the literature. Secondly, a biomechanical analysis of junior cricket fast bowlers will be performed to established the presence of identified risk factors among junior fast bowlers, as well as to measure bone health and muscle symmetry.
... This was another reason for the lack of differences between the groups. Previous studies showed that high prevalence of IDD in young adults [47,[53][54][55]. Alyas et al. reported that 39.4% incidence of disc degeneration in 33 asymptomatic elite adolescent tennis players [54]. ...
... Alyas et al. reported that 39.4% incidence of disc degeneration in 33 asymptomatic elite adolescent tennis players [54]. Elliott et al. reported a 21% incidence of disc degeneration or herniation in 24 male fast bowlers in cricket, who were bowling competitively freely, with a mean age of 13.7 years at a school and club level [53]. There was also no difference in the number of sit-up scores in 60 s between young fast bowlers with and without IDD in the study, showing 40 ± 7.5 and 34.5 ± 7 sit-ups scores, respectively [53]. ...
... Elliott et al. reported a 21% incidence of disc degeneration or herniation in 24 male fast bowlers in cricket, who were bowling competitively freely, with a mean age of 13.7 years at a school and club level [53]. There was also no difference in the number of sit-up scores in 60 s between young fast bowlers with and without IDD in the study, showing 40 ± 7.5 and 34.5 ± 7 sit-ups scores, respectively [53]. These study results were consistent with those of our study. ...
Background:
Previous studies suggested that patients with symptomatic intervertebral disc degeneration (IDD) of lumbar spine have reduced cross-sectional area (CSA) and functions of core muscles. However, reduced CSA and functions of core muscles have been observed not only in patients with symptomatic IDD but also in patients with other subgroups of low back pain (LBP). Thus, it is uncertain whether reduced CSA and functions of core muscles lead to IDD and LBP, or pain leads to reduced CSA and functions of core muscles in patients with symptomatic IDD. Therefore, this study aimed to compare the CSA and functions of core muscles between asymptomatic participants with and without IDD in magnetic resonance imaging (MRI).
Methods:
Twenty asymptomatic participants (12 men and 8 women) participated in this study. Ten participants had asymptomatic IDD at L4-5. The others were healthy controls (without IDD at all levels of lumbar spine). The CSA of core muscles was measured using MRI. Maximal isometric trunk flexor strength and side bridge strength were measured by a Smart KEMA strength sensor. Trunk flexor endurance test, side bridge endurance test and plank endurance test were used to measure core endurance. Double legs loading test was used to measure core stability. Mann-Whitney U test was used to compare the differences between two groups.
Results:
There were no significant differences in core muscle functions between the two groups (p > 0.05). Moreover, there was no significant difference in CSA between the two groups (p > 0.05).
Conclusions:
There was no significant difference in CSA and core muscle functions between asymptomatic participants with and without IDD. These findings indicate that a degenerative or bulging disc in asymptomatic individuals has little effect on CSA and functions of core muscles, especially in young age. Therefore, the general core endurance test or strength test could not differentiate asymptomatic people with and without IDD of lumbar spine.
Trial registration number:
Clinical Research information Service. KCT0004061. Registered 13 June 2019. retrospectively registered.
... All spinal injuries investigated the lumbar spine, and spinal stress fracture and disc degeneration were investigated through imaging in 9 % of articles [56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71]. Lumbar stress fracture and disc degeneration prevalence ranged from 21 % to 70 % in adult and youth cricketers [56, 59-62, 66, 68-70]. ...
... Adult cricketers were more likely to sustain a lumbar stress fracture compared to general population controls, [69] 3 out of 20 cricketers on one team sustained a new spinal fracture in one year, [56] and county cricketers sustained 0.17 lumbar stress fractures per 10 000 deliveries. [71] 69 % of spinal injury articles investigated lumbar stress fracture and disc degeneration injuries in youth cricketers [58-62, 64-68, 70]. Youth lumbar stress fracture and disc degeneration prevalence ranged from 21-70 % [60][61][62]66]. There was an increased risk of lumbar stress fracture in bowlers that had increased shoulder counter rotation and lumbar flexion during bowling biomechanical analysis [64]. ...
Summarising and synthesising the evidence on cricket health and wellbeing can help inform cricket stakeholders and navigate future research directions. The purpose of this study was to investigate the relationship between cricket participation, health and wellbeing at all ages and playing standards, and identify research gaps in the existing literature. A scoping review was performed from inception to March, 2020. Studies were included if they assessed a construct related to health and/or wellbeing in cricketers, available in English. 219 articles were eligible. Injury incidence per 1,000 player exposures ranged from 1.8-5.7 injuries. 48% of former cricketers experienced persistent joint pain. However, former cricketers reported greater physical activity levels and mental-components of quality of life compared to the general population. Heat injury/illness and skin cancer are concerns and require further research. Cricket participation is associated with an inherent injury risk, which may have negative implications for musculoskeletal health in later life. However, cricket participation is associated with high quality of life which can persist after retirement. Gaps in the literature include prospective studies on health and wellbeing of cricketers, female cricketers, injury prevention strategies, and the impact of cricket participation on metabolic health and lifetime physical activity.
... In a study of fast bowlers (Portus et al., 2004), 89% of players diagnosed with a bony stressinjury bowled with a mixed action. Until recently, the main factorhas been thought to be the large degree of shoulder counter-rotationin this action (Elliott et al., 1992;Elliott et al., 1993;Foster et al., 1989;Portus et al., 2004). questions the importance of shoulder counter-rotation as a causativefactor of stress injuries in the adult fast bowler. ...
The purpose of this study was to determine the risk factors of mixed action pace bowling technique in cricket. The subjects for the present study were male International cricket players from different countries. To collect necessary data the researcher used the videography of the subjects, which were recorded during the actual competition posted on YouTube. A search of Research Gate, Google Scholar, Medline was conducted to find relevant studies pertaining to cricket, cricket biomechanics, and mixed actions. Narrative review methods were used to synthesize the data. These data may be used to develop a model of scientific pace bowling technique for pace bowlers. The results of the study propose that a mixed bowling technique is associated with a higher prevalence of lumbar injuries. There is a need for appropriately designed interventions targeting modifiable factors.
... Further limitations to laboratory based studies have been outlined above. In addition, only 47% of studies reported actual p-values or statistical test values, however this may be related specifically to the question being investigated.It has been hypothesised that specific spinal kinematics, may contribute to increased risk of LBP and injury. 1 Although three-dimensional spinal pathomechanics are still relatively unclear; studies have identified significantly greater range of lateral flexion in injury/ LBP groups, as well as greater SCR angles.22,25,30 However, to date there is little research correlating threedimensional spinal kinematics with injury or LBP.22,24,30 ...
Background:
Fast bowlers display a high risk of lower back injury and pain. Studies report factors that may increase this risk, however exact mechanisms remain unclear.
Objective:
To provide a contemporary analysis of literature, up to April 2016, regarding fast bowling, spinal kinematics, ground reaction force (GRF), lower back pain (LBP) and pathology.
Method:
Key terms including biomechanics, bowling, spine and injury were searched within MEDLINE, Google Scholar, SPORTDiscuss, Science Citation Index, OAIster, CINAHL, Academic Search Complete, Science Direct and Scopus. Following application of inclusion criteria, 56 studies (reduced from 140) were appraised for quality and pooled for further analysis.
Results:
Twelve times greater risk of lumbar injury was reported in bowlers displaying excessive shoulder counter-rotation (SCR), however SCR is a surrogate measure which may not describe actual spinal movement. Little is known about LBP specifically. Weighted averages of 5.8 ± 1.3 times body weight (BW) vertically and 3.2 ± 1.1 BW horizontally were calculated for peak GRF during fast bowling. No quantitative synthesis of kinematic data was possible due to heterogeneity of reported results.
Conclusions:
Fast bowling is highly injurious especially with excessive SCR. Studies adopted similar methodologies, constrained to laboratory settings. Future studies should focus on methods to determine biomechanics during live play.
Elite cricket pace bowlers commonly sustain debilitating bone stress injuries. Lumbar bone stress injuries are more prominent in males, while lower limb bone stress injuries are more common in females. Bone stress injuries are partly attributable to bowling technique; however, scant research exists comparing bowling techniques of males and females as to better understand why males are more susceptible to lumbar bone stress injury. Three-dimensional pace bowling kinematics previously linked with lumbar bone stress injury were compared between 59 male and 19 female elite pace bowlers. Participants bowled 18 match-intensity deliveries indoors from a full run-up, whereby the mean of six deliveries was analyzed. Compared to females, males exhibited: a more extended thoraco-pelvic segment at back foot contact ( p = 0.039, g = 0.46), larger shoulder counter-rotation from back foot contact to front foot flat ( p = 0.021, g = 0.64), greater thoraco-pelvic lateral flexion at front foot flat ( p = 0.001, g = 0.95), larger front knee flexion at ball release ( p = 0.046, g = 0.57), and greater maximum front knee flexion from front foot flat to ball release ( p = 0.009, g = 0.57). Australian elite male pace bowlers performed techniques linked to lumbar bone stress injury to a much greater extent than their female counterparts. A straighter front leg technique observed in elite Australian females may be why they more commonly experience lower limb bone stress injuries via possibly higher vertical loading rates. This information may assist in developing sex-specific bone stress injury risk mitigation approaches.
Background
Lumbar spine injuries in fast bowlers account for the greatest missed playing time in cricket. A range of extrinsic and intrinsic variables are hypothesised to be associated with low back pain and lumbar spine injury in fast bowlers, and an improved understanding of intrinsic variables is necessary as these may alter load tolerance and injury risk associated with fast bowling. This review critically evaluated studies reporting intrinsic variables associated with low back pain and lumbar spine injury in fast bowlers and identified areas for future investigation.
Methods
OVID Medline, EMBASE, SPORTDiscus, CINAHL, Web of Science and SCOPUS databases were last searched on 3 June 2022 to identify studies investigating intrinsic variables associated with low back pain and lumbar spine injury in cricket fast bowlers. Terms relevant to cricket fast bowling, and intrinsic variables associated with lumbar spine injury and low back pain in fast bowlers were searched. 1,503 abstracts were screened, and 118 full‐text articles were appraised to determine whether they met inclusion criteria. Two authors independently screened search results and assessed risk of bias using a modified version of the Quality in Prognostic Studies tool.
Results
Twenty-five studies met the inclusion criteria. Overall, no included studies demonstrated a low risk of bias, two studies were identified as moderate risk, and twenty-three studies were identified as high risk. Conflicting results were reported amongst studies investigating associations of fast bowling kinematics and kinetics, trunk and lumbar anatomical features, anthropometric traits, age, and neuromuscular characteristics with low back pain and lumbar spine injury.
Conclusion
Inconsistencies in results may be related to differences in study design, injury definitions, participant characteristics, measurement parameters, and statistical analyses. Low back pain and lumbar spine injury occurrence in fast bowlers remain high, and this may be due to an absence of low bias studies that have informed recommendations for their prevention. Future research should employ clearly defined injury outcomes, analyse continuous datasets, utilise models that better represent lumbar kinematics and kinetics during fast bowling, and better quantify previous injury, lumbar anatomical features and lumbar maturation.
Trial registration
Open Science Framework https://doi.org/10.17605/OSF.IO/ERKZ2.
The biomechanics of the bowling delivery in cricket has been a subject of extensive research aimed at understanding the key kinematic and kinetic factors that contribute to optimal performance and injury prevention. This abstract presents a critical analysis of the existing literature on the biomechanics of the bowling delivery, highlighting the key findings, limitations, and areas for future research. The bowling delivery in cricket involves a complex sequence of movements that requires the coordination of various body segments. Studies have identified three main bowling techniques: side-on, front-on, and mixed, each characterized by distinct body alignments and orientations towards the batsman. Biomechanical analyses have revealed that these techniques differ in terms of the joint angles, muscle activations, and forces exerted during the delivery stride. One critical aspect of the bowling delivery is the transfer of energy from the lower body to the upper body. Research has shown that an efficient transfer of energy is crucial for generating ball speed and accuracy. Studies have explored the role of different kinematic variables, such as stride length, trunk flexion, and shoulder rotation, in optimizing this energy transfer. Furthermore, the biomechanics of the bowling delivery has been associated with the risk of injury, particularly in fast bowlers. The mixed bowling technique has been identified as having a higher risk of back injuries compared to side-on and front-on techniques. Understanding the biomechanical factors contributing to injury susceptibility can aid in the development of injury prevention strategies and workload management protocols. Despite the advancements in the field, several limitations exist in current biomechanical studies on the bowling delivery. Many studies have focused on laboratory-based analyses using motion capture systems, which may not fully capture the complexities of the game environment. Additionally, limited research has explored the influence of individual variations, such as player skill level, body composition, and fatigue, on bowling biomechanics. To advance the understanding of the biomechanics of the bowling delivery, future research should incorporate on-field analyses, consider individual variations, and explore the impact of fatigue and workload management on performance and injury risk. Furthermore, technological advancements, such as wearable sensors and real-time feedback systems, can provide valuable insights into the biomechanics of bowling in real-game scenarios. In conclusion, a critical analysis of the existing literature on the biomechanics of bowling delivery highlights the complex nature of this skill and its influence on performance and injury risk. Further research is warranted to address the limitations and explore new avenues, ultimately enhancing the knowledge base and practical applications for optimizing bowling performance and athlete well-being in cricket.
Study design:
Systematic review and meta-analysis.
Objective:
To provide an overview of the prevalence of reported musculoskeletal abnormalities on magnetic resonance imaging (MRI) of the pediatric spine.
Summary of background data:
Back pain is a common complaint and significant health issue, already in children. Several studies have investigated musculoskeletal abnormalities of the pediatric spine as possible cause of low back pain (LBP). However, it is not clear which abnormalities are the most prevalent among children.
Methods:
A systematic literature search on the prevalence of musculoskeletal spinal abnormalities on MRI in children was conducted in the Embase, Medline Ovid and Cochrane CENTRAL databases. Risk of bias was assessed using a checklist based on the Downs and Black checklist. General information on study and patient characteristics and the prevalence of spinal abnormalities were extracted from the studies. Prevalence data was presented in three subgroups: non-athletes without low back pain, participants with low back pain, and athletes. Prevalence data of the most reported abnormalities were pooled using random-effects proportion meta-analysis. The study protocol was prospectively registered in PROSPERO (CRD42017080543).
Results:
The search resulted in 16,783 articles, of which 31 articles (2,373 participants) were included in this systematic review. Two third of the studies had a low risk of bias. The pooled prevalence in non-athletes without LBP, participants with LBP, and athletes without LBP was respectively 22%, 44% and 22% for disc degeneration, 1%, 38% and 13% for herniated discs, 5%, 22% and 11% for endplate changes, and 0%, 30% and 6% for pars fractures.
Conclusions:
Disc degeneration, herniated discs, endplate changes, and spondylolysis are the most reported spinal abnormalities on MRI in children in literature. Spinal abnormalities seen in adults are already prevalent in children with LBP, with the highest prevalence for disc degeneration and herniated discs.
Level of evidence:
2.
The biomechanical analysis of elite cricket bowlers reported in this article, provides information which may assist in the development of a model that may be used in teaching young fast bowlers. The information reported may also aid in the identification of injury-producing factors associated with the bowling action. This article outlines some principles of fast bowling developed from the A.I.S. fast bowling cricket squad and states characteristics of fast bowling which were common to bowlers experiencing lower back, knee, shin and groin problems.
The 20 members of the Western Australian fast bowling development squad (mean age, 17.9 years), who had previously undergone routine computed tomography (CT) and magnetic resonance imaging (MRI) scans to detect the presence of bony and intervertebral disk abnormalities, acted as subjects for this study. While these radiologic data were being analyzed, these players were filmed both laterally (200 Hz) and from directly above (100 Hz) as their front foot impacted a force platform during the delivery stride of the fast bowling action. On a subsequent trial, kinetic data from the platform were recorded when their back foot impacted the force platform. In addition, these bowlers performed selected physical capacity tests. The occurrence of abnormal radiologic data were then used to group the bowlers (group 1: no abnormal radiologic features from CT or MRI scans; group 2: disk degeneration or bulging on MRI scan; group 3: spondylolysis, spondylolisthesis, or pedicle sclerosis). A Mann‐Whitney U‐rank test was then used to identify any significant differences (p < 0.05) between the groups for all dependent variables. Pars interarticularis and intervertebral disk abnormalities were commonly identified in this sample of fast bowlers (55 and 65%, respectively) and all players who had experienced back pain had evidence of a radiologic abnormality. No player with a normal diagnosis complained of pain. The appearance of these features was attributed to a combination of factors rather than a single cause. Bowlers who recorded poorer hamstring or low back flexibility predisposed themselves to a disk abnormality, whereas those who delivered the ball from a high release height relative to their standing height and players who had bowled over several seasons during their growth period were predisposed to a bony abnormality. Furthermore, bowlers who used a technique that combined a front‐on back foot placement and a side‐on shoulder alignment were more likely to present abnormal radiologic features in the lumbar spine.
Computed tomography can accurately distinguish a bulging disc with intact annulus from a herniated nucleus pulposus in most patients. A bulging annulus should be diagnosed when CT scans demonstrate generalized extension of the disc margins beyond the adjacent vertebral body margins. A herniated nucleus may be diagnosed by a CT scan when there is focal protrusion of the disc margin beyond the vertebral body margins. However, correlation between clinical and CT findings remains a critical factor in determining the significance of an abnormality detected by a CT scan.
Combining orthopedic surgery with biomechanical engineering, this reference and teaching text reviews and analyzes the clinical and scientific data on the mechanics of the human spine. This edition adds new material on vibration (i.e. road driving) and its effect on the spine; anatomy and kinematics
