|Year : 2021 | Volume
| Issue : 2 | Page : 134-140
Cervical spine range of motion and joint position sense in elite male cricketers: An observational study
Susan A Reid1, Johnathan Fornasier1, Daniel Redrup2, Shreya McLeod1
1 Discipline of Physiotherapy, School of Allied Health, Australian Catholic University, New South Wales, Australia
2 Cricket New South Wales, Australia
|Date of Submission||24-Jan-2020|
|Date of Decision||20-May-2020|
|Date of Acceptance||07-Aug-2020|
|Date of Web Publication||18-May-2021|
Dr. Shreya McLeod
Discipline of Physiotherapy, School of Allied Health, Australian Catholic University, 33 Berry Street, North Sydney 2060, North Sydney NSW 2059
Source of Support: None, Conflict of Interest: None
OBJECTIVE: The aims of the current study were to (1) establish baseline data for cervical range of motion (CROM) and joint position sense (JPS) in elite male cricketers, (2) determine whether these players had differences when compared to healthy adults, and (3) establish a reference set of values for future investigations.
MATERIALS AND METHODS: Design: Repeated measures, observational study. Participants: Thirty-one elite cricketers, aged 18–35 years. Setting: Cricket New South Wales at the Sydney Cricket Ground, Sydney, Australia. Outcome measures: Cervical rotation was measured with a CROM device and JPS using the joint position error (JPE) laser method with two protocols: repositioning to straight ahead and to 80% of maximum rotation.
RESULTS: Mean right and left rotation were less than healthy normals by 6.5° (P < 0.001) and 4.2° (P < 0.001), respectively. In the preseason, 26% of cricketers had JPE >4.5° repositioning to straight ahead, which is 11% greater than the general population and 87% had JPE >4.5° when repositioning to 80% rotation. Postseason, deficits in CROM were unchanged. Fewer players (22%) had JPE >4.5° when repositioning to straight ahead however JPE when repositioning to 80% of rotation increased 1° for both directions (P < 0.05).
CONCLUSIONS: Contrary to the authors' hypothesis, preliminary findings from this study demonstrated that elite male cricketers in this cohort had deficits in CROM and JPS, compared to normal healthy adults. This has clinical implications for the use of physical therapies targeting JPS and restoring CROM pre- and post-head and neck injury. Therapists should account for preexisting, baseline asymmetries in the range of motion and JPE in male cricketers. Further research needs to validate these findings across adolescent and female cricketers and explore the interaction between cervical spine parameters, cricket biomechanics, and head or neck injury risk.
Keywords: Cervical spine, cricketers, joint position sense, range of motion
|How to cite this article:|
Reid SA, Fornasier J, Redrup D, McLeod S. Cervical spine range of motion and joint position sense in elite male cricketers: An observational study. Int J Health Allied Sci 2021;10:134-40
|How to cite this URL:|
Reid SA, Fornasier J, Redrup D, McLeod S. Cervical spine range of motion and joint position sense in elite male cricketers: An observational study. Int J Health Allied Sci [serial online] 2021 [cited 2021 Jun 22];10:134-40. Available from: https://www.ijhas.in/text.asp?2021/10/2/134/316278
| Introduction|| |
Cricket is the most popular sport in Commonwealth and former Commonwealth countries in the world. Internationally, all three formats of the game (test, 50-over and 20-over matches) are played by men but are gaining popularity among women. Cricket requires three distinct disciplines: batting, bowling, and fielding.
Although considered a predominantly noncontact sport, direct impacts to the head, face, and neck by balls at high velocity are of concern in cricket.,,, In a recent study by Hill et al.  (2019), the rate of concussions was 2.3 and 2.0 concussions per 1000 player days in elite men's and women's cricket and 1 in 9000 and 1 in 6000 balls, respectively. Although significantly lower than in other collision sports,,, this was higher than previously reported in the cricket literature., Therefore, while the occurrences of head and neck trauma are low, the injuries sustained are serious and could lead to increased absence or permanent retirement from the sport.,
There has been growing interest in the association between neck range of motion (ROM) and joint position sense (JPS) in modifying the risk of sport-related concussion., Adequate control of head and neck kinematics are required in order to reduce the likelihood of the neck being forced into end-range positions, causing injury. Recent studies have identified poor cervical proprioception, reduced oculomotor performance, a history of headaches and neck pain at baseline as risk factors for sustaining a concussion.,,, Thus, the identification of a modifiable risk factor for concussion is critical, given the short and potential long-term effects of repeat concussions. Furthermore, therapies addressing the reduced cervical ROM (CROM) and poor JPS have been used by therapists following injury to the head or neck in athletic populations.,,, However, it is unclear whether these treatments are of benefit to individuals following head or neck injury when no baseline data exists in noncollision sports such as cricket.
Thus, the aims of the current study were to (1) establish baseline data for ROM and JPS in elite male cricketers, (2) determine whether these players had differences when compared to healthy adults, and (3) establish a reference set of values for future investigations.
| Material and Methods|| |
A convenience sample was used in this pilot, repeated measures observational study.
Players from two first class cricket teams were invited to participate in this study. Thirty-one participants met the inclusion criteria of being asymptomatic, elite cricketers, male and over 18 years of age. Eighteen of these were from a senior cricket team and 13 were from the Under 19 team. All participants provided written informed consent. This study was approved by the Australian Catholic University's Human Research Ethics Committee and Cricket New South Wales, Australia.
Participants were given a questionnaire to collect demographic information such as their age, number of years playing cricket, number of hours per week and weeks per year spent batting, whether they were a right-handed or left-handed batsman. Data were collected at their training facility in the preseason and at the end of the competition schedule.
Cervical range of motion
Cervical ROM was measured with a CROM device, which has been shown to have high intra- and inter-rated reliability. It has a low standard error of measurement (2.1° for left rotation and 2.6° for right rotation) and a low minimal detectable change (MDC) (4.9° left rotation and 6.1° right rotation). In this study, participants were instructed to turn their head as far as comfortable, three times in both directions, i.e., left and right rotation. The measures were then averaged and compared to a norm of 79°, as previously established in healthy, asymptomatic individuals of a similar age group.
Joint position sense
Cervical active JPS was measured using Revel's laser method, to record joint position error (JPE). A laser pointer attached to a headband was used to determine a participant's ability to relocate to the neutral starting position with the eyes closed after performing an active head movement, i.e., right or left rotation. The difference between the start and end positions was measured in millimeters and the JPE calculated in degrees. This method has been shown to have high reliability and validity. Errors in excess of 4.5° were considered indicative of abnormal JPE in healthy individuals of the same age. Players were seated 90 cm from the wall mounted bullseye target [Figure 1], with their heads facing forward. A head mounted laser was positioned on the bullseye and players were then blindfolded. Players rotated their heads 30° to one direction (confirmed by the CROM placed above their heads) and then returned to their perceived midline. Six attempts were performed in left and right rotation, respectively, with the measures for each direction averaged. The head was manually guided back to the true middle, the starting position, after each attempt. The difference between the start and end position of the laser beam on the target was measured in degrees using the bullseye target of Chen and Treleaven which uses the formula, angle = tan-1 (error distance/90 cm).
Subsequently, a second set of tests for cervical spine proprioception was performed. To replicate the head position while batting, participants were instructed to start with their head in 80% of their maximum right rotation. This angle was chosen as it closely replicated the rotated head position batsmen were in for long periods, without going to end range (i.e., in excess of 90% rotation), to avoid any potential end-range pain or stretch provocation. Participants were once again blindfolded and instructed to focus on this new start position. They were asked to rotate to the midline/straight ahead position and then back to the new starting position of 80% maximal rotation. This was performed six times and the difference between the start and end position measured in degrees.
| Questionnaire|| |
A sample size of 30 participants was calculated by an independent biostatistician from Australian Catholic University based on the previous research using cervical JPE as an outcome measure. All statistical analyses were performed using SPSS, version 22.0, (IBM Corp. Released 2013. IBM SPSS Statistics for Windows, Armonk, NY: IBM Corp., USA). Player characteristics were reported as means ± standard deviations (SD) for continuous variables (age, years playing, hours batting per week) and percentages for categorical variables (playing position and hand dominance). Cervical ROM and JPE scores were reported as mean values in degrees and SD for the group. Independent t-tests were used to compare participant results with published normative data. At an individual level, cervical ROM was compared to this normative value using the MDC for rotation to determine the cut-off point. A difference greater than this value would be considered as true variance and not measurement error. For JPE from straight ahead, the percentage with JPE greater than normal value (4.5°) was reported. Paired t-tests were used to identify differences between the right and left sides for cervical ROM and JPE. Statistical significance was set at P < 0.05.
| Results|| |
Thirty-one male cricketers aged between 18 and 35 (mean 23 ± 5) years were recruited for this study on a convenience basis. All individuals met the inclusion criteria of being injury-free at the time of assessment. Participants' characteristics are summarized in [Table 1].
Cervical range of motion
Cervical rotation was compared to the norm of 79° [Table 2].
|Table 2: Cervical rotation range of motion (degrees) compared to normative values|
Click here to view
Seventeen participants (55%) had a cervical ROM deficit greater than the MDC (4.9° for left rotation and 6.1° for right rotation). Of these 17, 11 participants (36%) from the total sample had bilateral restrictions of cervical ROM. Of the remaining six, four (13%) had right rotation deficits and two (6%) had left rotation deficits. Ten participants (32%) had differences (greater than the MDC) between their right and left rotation ROM, with six having less right rotation [Table 3].
|Table 3: Cervical rotation range of motion (degrees) and joint position error (degrees): Right versus left|
Click here to view
Joint position error
Relocating the straight-ahead position
While the mean JPE was within normal range, eight participants (26%) had JPE >4.5°. Of the eight participants with JPE in excess of 4.5°, two (6.5%) had bilateral errors, two (6.5%) had unilateral errors in the right rotation, and four (13%) in the left rotation. There were no significant differences between player groups for mean JPE in the right and left rotation [Table 3].
Relocating 80% of maximum rotation range
When relocating to the 80% rotation position, 87% of participants had >4.5° JPE in at least one direction. No significant difference was observed when comparing JPE from right to left. The participants demonstrated significantly greater JPE when performing head rotation to 80% compared to the straight ahead position for both right rotation (P < 0.001) and left rotation (P < 0.001).
Twenty-two of the original participants aged 18–35 years (24 ± 5.4) were re-assessed postseason. Some players were unavailable as they were either overseas or had finished their contracts. Five participants (22%) had mean JPE >4.5° to straight ahead in one direction. All participants had mean JPE >4.5° to 80% of maximum rotation in at least one direction. JPE when repositioning to 80% of rotation increased 1° for both directions. There were no significant differences between preseason measures of rotation ROM and JPE to straight ahead compared to those postseason. Although not significant, when relocating 80% of maximum rotation, JPE was >4.5° at the postseason assessment than at preseason.
| Discussion|| |
This is the first study to assess cervical rotation ROM and JPE in a small group of elite male cricketers. In the study, cricketers demonstrated differences in cervical spine ROM, when compared to healthy adults, possibly due to the asymmetrical demands of the sport. JPE was primarily within normal limits.
Cervical range of motion
Deficits were observed in the right and left cervical ROM, with 11 (34%) participants demonstrating bilateral restrictions in this group. This was a surprising finding as the players were completely asymptomatic at the time of testing, both at pre- and post-season. The plausible reasons for this reduction in range may be due to mechanical changes in the tissues or an adaptation to the asymmetrical nature of the sport,, rather than a factor associated with injury. Asymmetry implies an abnormal load through the spine and warrants intervention to correct this, however, it may be a necessary adaptation to the repetitive loading associated with the sport. Cricketers clearly spend hours practicing and refining their skills. Mann et al.  (2013)reported that elite batsmen develop the unique ability to couple their head movements to that of the ball coming toward them. Batters are often coached to move their heads toward the line of the ball so that it will be directly above the ball when it is hit or rotate their heads downward so that the ball is hit under their nose.,
Patients with chronic neck pain following whiplash have benefited from targeted therapies aimed at restoration of cervical ROM and normalization of sensorimotor impairments.,, However, it stands to reason, that if the cricketers in our cohort demonstrated deficits in ROM without symptomology, therapies used to alter or improve range may not be warranted. This has certainly been the case in fast bowlers where asymmetries are commonly observed in lumbar musculature., A study by Gray et al. (2016) suggested that in pace bowlers, asymmetries were in fact protective and that symmetry of abdominal musculature was associated with low back pain. This was thought to be an adaptive process by the trunk musculature, to meet the requirements of fast bowling. Hides et al. (2010) found that in a larger cohort of cricketers including spinners, pace bowlers and batsmen, differences were observed in cross-sectional areas between lumbar spine muscles on the dominant side, and contralateral abdominal musculature on the nondominant side. Thus, asymmetries in cervical ROM observed in our cohort may be simply an adaptation to the demands of the sport. This is of importance in batters, where the neck is required to stabilize the head while the batter watches the ball. The mechanism behind this reduction in ROM remains unclear and further longitudinal research is required to explore the mechanisms leading to this reduction in ROM, with reference to batting and bowling biomechanics and whether there is any association with injury.
Joint position error
The participants' mean JPE for both right and left rotations were within the normal limits. Pinsault et al. (2010) clearly stated that young elite sports players not playing contact sports should demonstrate normal JPE of approximately 2.5 ± 0.3°, as indicated in our results. However, it is important to note that clinical repositioning thresholds vary between studies. A threshold of 4.5° was set in certain studies,, however, many studies evaluating JPE in neck pain or whiplash associated disorders report mean values <4°., The difference in thresholds could be due to the methodological variations used to determine JPE and therefore, may not be clinically significant. As our participants were comparable with healthy, asymptomatic individuals, a clinical repositioning threshold of >4.5° as set., Eight participants (26%) in this study did demonstrate JPEs >4.5° when relocating to the straight ahead position. This was 11% higher than in the normal population. In addition, players had JPE in excess of 4.5° when the head was rotated to 80% compared to the straight ahead position, in both directions. The position of 80% rotation, although chosen to mimic batting, did have the potential to create skin stretch or activation of cutaneous receptors, influencing the JPE. Further studies may need to consider JPS testing in various ranges of rotation to minimize the effects of skin stretch on outcomes. In addition, a newer test such as the trunk relocation test with the stationary head position may more closely replicate a batter's stance position and reduce the input from the vestibular system in sensorimotor testing.
As concussions are on the rise in cricket,, there has been increasing interest in identifying and addressing potential risk modifiers., CROM, JPS and strength have been identified as potential risk modifiers.,,, Research in this field is sparse and has primarily focused on collision sports. Schneider et al. found that ice hockey players who reported headaches, neck pain, and dizziness preseason, performed significantly worse on cervical spine measures of strength, endurance, and JPS following a concussion. In the acute time period following concussion, 58% of players also reported an increase in headaches and 42%, an increase in neck pain. In Rugby Union players, Hides et al. reported altered trunk muscle function and cervical JPS, compared to preseason measures. Thus, there is emerging evidence that a thorough cervical spine assessment is warranted to identify potential cervical consequences of concussion.,, However, these findings are not yet applicable to noncollision sports. Furthermore, it has become apparent in our study that elite cricketers do in fact have preexisting asymmetries at baseline, irrespective of injury. From our results, the clinical implications are that preexisting asymmetries do exist in the elite cricketing population which may not require correction and may not correlate with injury.
Limitations of the study
The present results should be interpreted with consideration of several limitations. The use of a small convenience sample of elite male players might not have been large enough to gain satisfactory statistical power, as displayed in the post hoc analysis. Due to the small sample size, participants could not be stratified according to their playing position and expertise. Nine of the 22 participants were unavailable for postseason re-assessment, due to termination of their contracts, which was a significant proportion of the cohort. In addition, as this was a baseline study, we did not correlate cervical spine ROM and JPE with head and neck injuries sustained throughout the season or with prior injury and hence cannot draw conclusions regarding the alterations in ROM and JPE seen in this study. Still, this sample of cricketers was chosen to represent an asymptomatic baseline, in order to conduct future investigations.
Future directions could include the prospective and longitudinal monitoring of a larger cohort of players for changes in ROM and JPE, to establish a relationship between these measures and head and neck trauma. Within this, it would be of interest to see if the asymmetrical neck rotation associated with batting is strongly correlated with joint stiffness and loss of JPS, taking into consideration other factors such as hand dominance and hours spent batting. With increasing female participation in cricket, baseline measures clearly need to be identified in this cohort and monitored over the course of multiple seasons. The treatment of underlying deficits needs to be considered.
| Conclusions|| |
This was the first study to assess cervical rotation ROM and JPE in a small group of elite male cricketers. Deficits in cervical ROM were found in a significant proportion of this cohort. JPE was primarily within normal limits, except for rotation to 80%. These may be clinically relevant findings as physical therapies are often employed to restore cervical spine ROM and JPS following head and neck injuries in players, irrespective of baseline values. Given that players in this cohort demonstrated asymmetries at baseline and at postseason indicates that asymmetries may in fact be an adaptation to the sport. Future investigations need to consider these preliminary baseline values when interpreting the inter-relationships between cervical spine ROM, JPE, and head or neck injury.
We would like to acknowledge Professor Jenny Peat and Dr. Michael Steele for their assistance with statistical procedures. We would also like to thank Dr. John Orchard for access to the concussion surveillance database. Finally, we would like to thank Mr. Cameron New, Mr. Ned Coleman and Mr. Andrew Zhang for helping with data collection.
Financial support and sponsorship
Funds were provided to Johnathon Fornasier by the Australian Catholic University Faculty of Health Sciences Student Support Scheme (FHSSS).
Conflicts of interest
There are no conflicts of interest
| References|| |
Pandey CR. Sport Injury: Cricket Injury Epidemiology, Mechanisms and Prevention. 2nd
ed. Berliner: Heidelberg: Springer; 2015.
Martin C, Olivier B, Benjamin N. The functional movement screen in the prediction of injury in adolescent cricket pace bowlers: An observational study. J Sport Rehabil 2017;26:386-95.
Hill T, Orchard J, Kountouris A. Incidence of concussion and head impacts in Australian elite-level male and female cricketers after head impact protocol modifications. Sports Health 2019;11:180-5.
Tripathi M, Shukla DP, Bhat DI, Bhagavatula ID, Mishra T. Craniofacial injuries in professional cricket: No more a red herring. Neurosurg Focus 2016;40:E11.
Orchard J, Dhillon M, Farhart P, Blanch P, Kountouris A. Injury data and arguments to support a rule change to allow substitutes in test and first class cricket. Sports Physiol 2012;4:20-3.
Saw AE, McIntosh AS, Kountouris A, Newman P, Gaida JE. Vertebral artery dissection in sport: A systematic review. Sports Med 2019;49:553-64.
Gardner AJ, Iverson GL, Williams WH, Baker S, Stanwell P. A systematic review and meta-analysis of concussion in rugby union. Sports Med 2014;44:1717-31.
King D, Brughelli M, Hume P, Gissane C. Assessment, management and knowledge of sport-related concussion: Systematic review. Sports Med 2014;44:449-71.
McCrory P, Meeuwisse WH, Aubry M, Cantu RC, Dvorak J, Echemendia RJ, et al
. Consensus statement on concussion in sport—the 4th
International Conference on Concussion in Sport held in Zurich, November 2012. PM R 2013;5:255-79.
Orchard JW, Kountouris A, Sims K. Incidence and prevalence of elite male cricket injuries using updated consensus definitions. Open Access J Sports Med 2016;7:187-94.
Stretch R. A five-year investigation into the incidence and nature of cricket injuries in elite South African schoolboy cricketers. Br J Sports Med 2014;48:663.
Alsalaheen B, Johns K, Bean R, Almeida A, Eckner J, Lorincz M. Women and men use different strategies to stabilize the head in response to impulsive loads: Implications for concussion injury risk. J Orthop Sports Phys Ther 2019;49:779-86.
Hides JA, Franettovich Smith MM, Mendis MD, Treleaven J, Rotstein AH, Sexton CT, et al
. Self-reported concussion history and sensorimotor tests predict head/neck injuries. Med Sci Sports Exerc 2017;49:2385-93.
Mihalik JP, Guskiewicz KM, Marshall SW, Greenwald RM, Blackburn JT, Cantu RC. Does cervical muscle strength in youth ice hockey players affect head impact biomechanics? Clin J Sport Med 2011;21:416-21.
Kiefer AW, DiCesare C, Nalepka P, Foss KB, Thomas S, Myer GD. Less efficient oculomotor performance is associated with increased incidence of head impacts in high school ice hockey. J Sci Med Sport 2018;21:4-9.
Schneider KJ, Meeuwisse WH, Kang J, Schneider GM, Emery CA. Preseason reports of neck pain, dizziness, and headache as risk factors for concussion in male youth ice hockey players. Clin J Sport Med 2013;23:267-72.
Register-Mihalik JK, Mihalik JP, Guskiewicz KM. Association between previous concussion history and symptom endorsement during preseason baseline testing in high school and collegiate athletes. Sports Health 2009;1:61-5.
Lucke-Wold BP, Turner RC, Logsdon AF, Bailes JE, Huber JD, Rosen CL. Linking traumatic brain injury to chronic traumatic encephalopathy: Identification of potential mechanisms leading to neurofibrillary tangle development. J Neurotrauma 2014;31:1129-38.
Schneider KJ, Meeuwisse WH, Nettel-Aguirre A, Barlow K, Boyd L, Kang J, et al
. Cervicovestibular rehabilitation in sport-related concussion: A randomised controlled trial. Br J Sports Med 2014;48:1294-8.
Alsalaheen BA, Mucha A, Morris LO, Whitney SL, Furman JM, Camiolo-Reddy CE, et al
. Vestibular rehabilitation for dizziness and balance disorders after concussion. J Neurol Phys Ther 2010;34:87-93.
Chan C, Iverson GL, Purtzki J, Wong K, Kwan V, Gagnon I, et al
. Safety of active rehabilitation for persistent symptoms after pediatric sport-related concussion: A randomized controlled trial. Arch Phys Med Rehabil 2018;99:242-9.
Reneker J, Hassen A, Phillips R, Moughiman M, Donaldson M, Moughiman J. Feasibility of early physical therapy for dizziness after a sports-related concussion: A randomized clinical trial. Scand J Med Sci Sports 2017;27:2009-18.
Wibault J, Vaillant J, Vuillerme N, Dedering Å, Peolsson A. Using the cervical range of motion (CROM) device to assess head repositioning accuracy in individuals with cervical radiculopathy in comparison to neck- healthy individuals. Man Ther 2013;18:403-9.
Youdas JW, Carey JR, Garrett TR. Reliability of measurements of cervical spine range of motion—comparison of three methods. Phys Ther 1991;71:98-104.
Roren A, Mayoux-Benhamou MA, Fayad F, Poiraudeau S, Lantz D, Revel M. Comparison of visual and ultrasound based techniques to measure head repositioning in healthy and neck-pain subjects. Man Ther 2009;14:270-7.
Chen X, Treleaven J. The effect of neck torsion on joint position error in subjects with chronic neck pain. Man Ther 2013;18:562-7.
Portelli A, Reid SA. Cervical proprioception in a young population who spend long periods on mobile devices: A 2-group comparative observational study. J Manipulative Physiol Ther 2018;41:123-8.
Treleaven J, Jull G, LowChoy N. The relationship of cervical joint position error to balance and eye movement disturbances in persistent whiplash. Man Ther 2006;11:99-106.
Dall'Alba PT, Sterling MM, Treleaven JM, Edwards SL, Jull GA. Cervical range of motion discriminates between asymptomatic persons and those with whiplash. Spine (Phila Pa 1976) 2001;26:2090-4.
Martin C, Olivier B, Benjamin N. Asymmetrical abdominal muscle morphometry is present in injury free adolescent cricket pace bowlers: A prospective observational study. Phys Ther Sport 2017;28:34-42.
Kountouris A, Portus M, Cook J. Quadratus lumborum asymmetry and lumbar spine injury in cricket fast bowlers. J Sci Med Sport 2012;15:393-7.
Gray J, Aginsky KD, Derman W, Vaughan CL, Hodges PW. Symmetry, not asymmetry, of abdominal muscle morphology is associated with low back pain in cricket fast bowlers. J Sci Med Sport 2016;19:222-6.
Mann DL, Spratford W, Abernethy B. The head tracks and gaze predicts: How the world's best batters hit a ball. PLoS One 2013;8:e58289.
Croft JL, Button C, Dicks M. Visual strategies of sub-elite cricket batsmen in response to different ball velocities. Hum Mov Sci 2010;29:751-63.
Land MF, McLeod P. From eye movements to actions: How batsmen hit the ball. Nat Neurosci 2000;3:1340-5.
Jull G, Falla D, Treleaven J, Hodges P, Vicenzino B. Retraining cervical joint position sense: The effect of two exercise regimes. J Orthop Res 2007;25:404-12.
Jull GA, Falla D, Vicenzino B, Hodges PW. The effect of therapeutic exercise on activation of the deep cervical flexor muscles in people with chronic neck pain. Man Ther 2009;14:696-701.
Falla D, Lindstrøm R, Rechter L, Boudreau S, Petzke F. Effectiveness of an 8-week exercise programme on pain and specificity of neck muscle activity in patients with chronic neck pain: A randomized controlled study. Eur J Pain 2013;17:1517-28.
Ranson C, Burnett A, O'Sullivan P, Batt M, Kerslake R. The lumbar paraspinal muscle morphometry of fast bowlers in cricket. Clin J Sport Med 2008;18:31-7.
Hides J, Stanton W, Freke M, Wilson S, McMahon S, Richardson C. MRI study of the size, symmetry and function of the trunk muscles among elite cricketers with and without low back pain. Br J Sports Med 2008;42:809-13.
Hides JA, Stanton WR, Wilson SJ, Freke M, McMahon S, Sims K. Retraining motor control of abdominal muscles among elite cricketers with low back pain. Scand J Med Sci Sports 2010;20:834-42.
Pinsault N, Anxionnaz M, Vuillerme N. Cervical joint position sense in rugby players versus non-rugby players. Phys Ther Sport 2010;11:66-70.
Revel M, Andre-Deshays C, Minguet M. Cervicocephalic kinesthetic sensibility in patients with cervical pain. Arch Phys Med Rehabil 1991;72:288-91.
Kristjansson E, Dall'Alba P, Jull G. A study of five cervicocephalic relocation tests in three different subject groups. Clin Rehabil 2003;17:768-74.
Treleaven J, Jull G, Sterling M. Dizziness and unsteadiness following whiplash injury: Characteristic features and relationship with cervical joint position error. J Rehabil Med 2003;35:36-43.
Armstrong BS, McNair PJ, Williams M. Head and neck position sense in whiplash patients and healthy individuals and the effect of the cranio-cervical flexion action. Clin Biomech (Bristol, Avon) 2005;20:675-84.
Revel M, Minguet M, Gregoy P, Vaillant J, Manuel JL. Changes in cervicocephalic kinesthesia after a proprioceptive rehabilitation program in patients with neck pain: A randomized controlled study. Arch Phys Med Rehabil 1994;75:895-9.
Strimpakos N. The assessment of the cervical spine. Part 1: Range of motion and proprioception. J Bodyw Mov Ther 2011;15:114-24.
Bonfield CM, Shin SS, Kanter AS. Helmets, head injury and concussion in sport. Phys Sportsmed 2015;43:236-46.
Schneider KJ, Meeuwisse WH, Palacios-Derflingher L, Emery CA. Changes in measures of cervical spine function, vestibulo-ocular reflex, dynamic balance, and divided attention following sport-related concussion in elite youth ice hockey players. J Orthop Sports Phys Ther 2018;48:974-81.
Hides JA, Franettovich Smith MM, Mendis MD, Smith NA, Cooper AJ, Treleaven J, et al
. A prospective investigation of changes in the sensorimotor system following sports concussion. An exploratory study. Musculoskelet Sci Pract 2017;29:7-19.
Schneider KJ. Concussion-Part I: The need for a multifaceted assessment. Musculoskelet Sci Pract 2019;42:140-50.
Kennedy E, Quinn D, Tumilty S, Chapple CM. Clinical characteristics and outcomes of treatment of the cervical spine in patients with persistent post-concussion symptoms: A retrospective analysis. Musculoskelet Sci Pract 2017;29:91-8.
[Table 1], [Table 2], [Table 3]