Creatine supplementation during college football training does not increase the incidence of cramping or injury

The purpose of this study was to examine the effects of creatine supplementation on the incidence of injury observed during 3-years of NCAA Division IA college football training and competition. In an open label manner, athletes participating in the 1998–2000 football seasons elected to take creatine or non-creatine containing supplements following workouts/practices. Subjects who decided to take creatine were administered 15.75 g of creatine for 5 days followed by ingesting an average of 5 g/day thereafter administered in 5–10 g doses. Creatine intake was monitored and recorded by research assistants throughout the study and ranged between 34–56% of players during the course of the study. Subjects practiced or played in environmental conditions ranging from 8–40°C (mean 24.7 ± 9°C) and 19–98% relative humidity (49.3 ± 17%). Injuries treated by the athletic training staff were recorded and categorized as cramping, heat/dehydration, muscle tightness, muscle strains/pulls, non-contact joint injuries, contact injuries, and illness. The number of missed practices due to injury/illness was also recorded. Data are presented as the total number of treated injuries for creatine users/total injuries observed and percentage occurrence rate of injuries for creatine users for all seasons. The incidence of cramping (37/96, 39%), heat/dehydration (8/28, 36%), muscle tightness (18/42, 43%), muscle pulls/strains (25/51, 49%), non-contact joint injuries (44/132, 33%), contact injuries (39/104, 44%), illness (12/27, 44%), number of missed practices due to injury (19/41, 46%), players lost for the season (3/8, 38%), and total injuries/missed practices (205/529, 39%) were generally lower or proportional to the creatine use rate among players. Creatine supplementation does not appear to increase the incidence of injury or cramping in Division IA college football players.     

Influence of playing position on the site, nature, and cause of rugby league injuries

This study investigated the influence of playing position on the site, nature, and cause of injuries in rugby league. The incidence, site, nature, and cause of playing injuries was prospectively studied in 156 rugby league players over 2 seasons. An injury was defined as any pain or disability suffered by a player during a match that resulted in the player missing a subsequent match. The hooker (101 per 1,000 playing hours) and prop (92 per 1,000 playing hours) positions had the highest incidence of injury. Injuries sustained by the fullback (32 per 1,000 playing hours) and halfback (44 per 1,000 playing hours) positions were less common. Compared with other individual playing positions, props had a significantly higher incidence of overexertion injuries (22 per 1,000 playing hours), thigh and calf injuries (47 per 1,000 playing hours), and hematomas (19 per 1,000 playing hours), whereas the five-eighth position (31 per 1,000 playing hours) and the hookers and halves positional group (17 per 1,000 playing hours) had a significantly higher incidence of falling and stumbling injuries. These results demonstrate that the hooker and prop positions have higher injury rates than other rugby league positions. Furthermore, the site, type, and cause of injuries are different among individual playing positions and playing groups. These findings suggest that individual position training for injury prevention is warranted in rugby league.     

Cervical spine injuries in rugby players.

Nine patients with serious cervical spine injuries that occurred while they were playing rugby were seen in a British Columbia acute spinal cord injury unit during the period 1975-82. All the injuries had occurred during the "scrum" or the "tackle". Two of the patients were rendered permanently quadriplegic, and one patient died. There is a need for a central registry that would record all cervical spine injuries in rugby players as well as for changes in the rules of the game.     

The relationship between preseason range of motion and muscle strain injury in elite soccer players

The purpose of the study was to determine the influence of preseason lower-extremity range of motion (ROM) on the risk of muscle strain injury during a competitive season for elite soccer players. Thirty-six elite male soccer players (age, 25.6 +/- 4.7 years) had maximum static ROM for 6 movements of the lower extremity measured prior to the 2003-2004 English Premier League season. Player age, body size, dominant limb, and playing position were documented also. All lower-extremity muscle strain injuries were recorded prospectively during the competitive season, as was the total amount of time spent in training and games for each player. Soccer players sustaining a muscle strain injury in the hip flexors or knee flexors had lower preseason ROM (p < 0.05) in these muscle groups compared with uninjured players. Similar trends were observed for the remaining muscle groups, but all failed to reach statistical significance (p > 0.05). Most significantly, soccer players with lower preseason ROM in the hip flexors and knee flexors had a statistically higher risk for a muscle strain injury to these muscle groups during a competitive season. Age, body size, limb dominance, and playing position were not significant intrinsic risk factors for the development of muscle strain injuries. Screening of flexibility for soccer players should be conducted during preseason, and flexibility training should be prescribed to players with reduced ROM to lower the risk of developing a muscle strain injury.     

8. Blessures au hockey majeur: 3 ans d'étude

In a major junior hockey team there were 238 injuries in 257 games during the three seasons of 1973-76 (mean number of injuries per game, 0.926). Incapacity from these injuries resulted in a loss of 345 practices and 299 games (mean number per injury, 1.45 and 1.26, respectively). The site of the game, whether at home or out of town, and the period in which the injury occurred did not seem to be important. Risk of injury seemed to be greatest in the defensive zone. Forwards were the most often injured, their injuries accounting for 45.8% of the total; defensive players were next most often hurt (31.9%). The age of the injured players ranged from 16 to 19 years, those 19 years old predominating (42.0%).There were 91 injuries of the lower limb (38.2% of the total), the knee being the site most frequently injured (31 injuries; 34.1% of the 91), and 74 injuries of the upper limb, the shoulder being the site most frequently injured (25 injuries; 33.8% of the 74). The main causes of injury were a blow by the puck (frequency, 21.0%), a check (18.5%), a blow by a stick (14.7%) and a fight (13.4%).     

Biomechanical assessment of the effects of significant hamstring injury: an isokinetic study

Soccer players may develop recurrent hamstring injuries. This may be due to inadequate rehabilitation or to recurrent injury. In addition, following injury, the hamstring muscular complex may be permanently damaged, resulting in decreased strength, and increased likelihood of recurrent injury. Fourteen professional soccer players were assessed by clinical examination and by isokinetic testing with a Cybex II machine. Seven had suffered moderate or major hamstring injuries in the past year. There were seven controls. None of the hamstring group were currently suffering from an acute hamstring injury. The results of the two groups were compared. There were no differences in the mean results. This pilot study suggests that no permanent functional damage occurs to the muscular complex after moderate or major hamstring injuries after correct treatment. However, further research is required to confirm this.     

Stimulation of the spinal cord in the treatment of traumatic injuries of cervical spine

Since 1974, clinical experiments have been conducted at the Rehabilitation Clinic in Konstancin (Poland) on the effects of electrostimulation on the damaged spinal cord. 30 patients with stimulation after injury to the cervical spinal cord are reported. Patients with complete and incomplete cervical cord injury were compared. The patients were treated by surgical decompression with simultaneous implantation of stimulating electrodes in contact with the spinal cord. The control group of patients were operated upon in the same period for similar injuries, but had no stimulators implanted. Neurological improvement was better in the stimulated compared to the nonstimulated patients, both as regards number of neurological improvements as well as quality of neurological function. The comparison also confirmed a favorable effect of spinal cord stimulation on the development of bladder automatism.     

Retinal detachment following hockey injury.

Thirty-three cases of retinal detachment following hockey injury were seen during a 15-year period at the retina clinic of Maisonneuve-Rosemont Hospital, Montreal. Most injuries occurred in adolescents, the average age being 18 years. The mean interval between injury and preoperative examination was 3 years. Almost half of these young hockey players remained legally blind in the affected eye even after a successful operation. A helmet with a protective face visor is suggested as the best prevention against severe ocular damage such as retinal detachment.     

Spinal injuries due to front-end bale loaders.

Of 22 patients admitted to Plains Health Centre, Regina, from January 1979 to April 1986 with spinal injuries due to farming accidents, 7 had injuries related to tractor-mounted front-end bale loaders. In contrast, none of the 12 patients admitted with farm-related spinal injuries from 1974 through 1978 had injuries related to bale loaders. All seven injuries occurred when a front-end loader was used to move a large, round hay bale. In each case when the loader arms were raised past the horizontal plane the bale rolled back onto the unprotected tractor operator. There were five thoracic injuries, one cervical injury and one lumbar injury. All seven bony injuries healed. Four of the patients had permanent neurologic sequelae; two of the four had paraplegia. All seven patients suffered disability that impaired work performance; all five farmers suffered some loss of income. None of these injuries would have occurred if available safety equipment had been in place.     

Microglial activation in different models of peripheral nerve injury of the rat

Pain and pain modulation has been viewed as being mediated entirely by neurons. However, new research implicates spinal cord glia as key players in the creation and maintenance of pathological pain. Sciatic nerve lesions are one of the most commonly studied pain-related injuries. In our study we aimed to characterize changes in microglial activation in the rat spinal cord after axotomy and chronic constriction injury of the sciatic nerve and to evaluate this activation in regard to pain behavior in injured and control groups of rats. Microglial activation was observed at ipsilateral side of lumbar spinal cord in all experimental groups. There were slight differences in the level and extent of microglial activation between nerve injury models used, however, differences were clear between nerve-injured and sham animals in accordance with different level of pain behavior in these groups. It is known that activated microglia release various chemical mediators that can excite pain-responsive neurons. Robust microglial activation observed in present study could therefore contribute to pathological pain states observed following nerve injury.     

Training injuries in rugby league: an evaluation of skill-based conditioning games

This study investigated the site and nature of rugby league training injuries, and identified the training activities that were most likely to result in injury in rugby league players. The incidence of training injuries was prospectively studied in 60 semiprofessional rugby league players over 1 season. Injury data was collected from 72 training sessions, which included all preseason and in-season training sessions. Injuries were described according to site, type, and the training activity performed at the time of injury. The majority of injuries (90.9 per 1000 training hours, 37.5%) were sustained in traditional conditioning activities that involved no skill component (i.e., running without the ball). In contrast, the incidence of injuries sustained while participating in skill-based conditioning games (26.0 per 1000 training hours, 10.7%) was low. These results suggest that skill-based conditioning games offer a safe, effective method of conditioning for rugby league players.     

Developmental biomechanics of the cervical spine: Tension and compression

Epidemiological data and clinical indicia reveal devastating consequences associated with pediatric neck injuries. Unfortunately, neither injury prevention nor clinical management strategies will be able to effectively reduce these injuries or their effects on children, without an understanding of the cervical spine developmental biomechanics. Thus, we investigated the relationship between spinal development and the functional (stiffness) and failure biomechanical characteristics of the cervical spine in a baboon model. A correlation study design was used to define the relationships between spinal tissue maturation and spinal biomechanics in both tension and compression. Eighteen baboon cervical spine specimens distributed across the developmental spectrum (1–26 human equivalent years) were dissected into osteoligamentous functional spinal units. Using a servo-hydraulic MTS, these specimens (Oc–C2, C3–C4, C5–C6, C7–T1) were non-destructively tested in tension and compression and then displaced to failure in tension while measuring the six-axes of loads and displacements. The functions describing the developmental biomechanical response of the cervical spine for stiffness and normalized stiffness exhibited a significant direct relationship in both tension and compression loading. Similarly, the tensile failure load and normalized failure load demonstrated significant maturational increases. Further, differences in biomechanical response were observed between the spinal levels examined and all levels exhibited clinically relevant failure patterns. These data support our understanding of the child cervical spine from a developmental biomechanics perspective and facilitate the development of injury prevention or management schema for the mitigation of child spine injuries and their deleterious effects.     

Differential Changes in Neuronal Excitability in the Spinal Dorsal Horn After Spinal Nerve Ligation in Rats

Previous studies demonstrated that peripheral nerve injury induced excessive neuronal response and glial activation in the spinal cord dorsal horn, and such change has been proposed to reflect the development and maintenance of neuropathic pain states. The aim of this study was to examine neuronal excitability and glial activation in the spinal dorsal horn after peripheral nerve injury. We examined noxious heat stimulation-induced c-Fos protein-like immunoreactivity (Fos-LI) neuron profiles in fourth-to-sixth lumbar (L4–L6) level spinal dorsal horn neurons after fifth lumbar spinal nerve ligation (L5 SNL). Immunofluorescence labeling of OX-42 and GFAP was also performed in histological sections of the spinal cord. A significant increase in the number of Fos-LI neuron profiles in the spinal dorsal horn at the L4 level was found at 3 days after SNL, but returned to a level similar to that in sham-operated controls by 14 days after injury. As expected, a decrease in the number of Fos-LI neuron profiles in the spinal dorsal horn at the L5 level was found at 3 days after SNL. However, these profiles had reappeared in large numbers by 14 and 21 days after injury. Immunofluorescence labeling of OX-42 and GFAP indicated sequential activation of microglia and astrocytes in the spinal dorsal horn. We conclude that nerve injury causes differential changes in neuronal excitability in the spinal dorsal horn, which may coincide with glial activation. These changes may play a substantial role in the pathogenesis of neuropathic pain after peripheral nerve injury.     

Injuries of the spine sustained in rugby.

Between 1952 and 1982, 67 rugby players (63 rugby union, two rugby league, and two American football) sustained serious injuries of their spine. The injuries fell predominantly on the lower cervical spine. Forty eight of the players sustained serious injuries of the spinal cord, leading to paralysis and total incapacity. The incidence of such injuries appears to have increased in recent years, particularly those incurred in tackles and mauls and rucks, and particularly among schoolboys. Changes in the laws of the game and in the attitudes of the players over the past few years should improve play and lead to a lower incidence of injuries.     

Effects of autophagy on acid-sensing ion channel 1a-mediated apoptosis in rat articular chondrocytes

The incidence of spinal cord injuries (SCI) is high every year. As the spinal cord is the highway that allows for the brain to control the rest of the body, spinal cord injuries greatly impact the quality of life of the patients. The SCI include the primary response consisting of the initial accident-induced damage and the secondary response that is characterized by damage due to inflammation and biological responses. Astrocytes are the first to act at the site of the injury, forming a glial scar and attracting immune cells. The immune system plays a role in cleaning out the debris caused by the injury, as well as preventing neurons to grow and heal. The secondary injury caused by the inflammatory response is the major target to combat SCI. This article critically reviews the key players in the inflammatory SCI response and potential therapies, specifically targeting astrocytes, neutrophils, and macrophages. These cells are both beneficial and detrimental following SCI, depending on the released molecules and the types of cells infiltrated to the site of injury. Indeed, depending on the subtype of macrophages, M1 or M2, beneficial or detrimental response could be incited. Therapeutic strategies to regulate and manipulate the immune cells via increasing or decreasing their recruitment to the site of injury could be developed together with upregulating and downregulating the release of certain chemicals from the infiltrated cells.     

Missed injuries of the spinal cord.

Damage to the spinal cord had not been recognised initially in 15 patients out of a consecutive series of 353 admitted over a decade to the National Spinal Injuries Centre with paralysis due to trauma to the cord. In some patients the missed diagnosis led to mismanagement and a greater neurological deficit. Missed injuries of the spinal cord are seen in patients with multiple injuries and head injuries and in those without any paralysis. Various radiological errors contribute to the failure to recognise the vertebral injury. In addition to causing severe disability to the victim these missed and mismanaged injuries of the spinal cord cost the National Health Service large sums in compensation. A careful evaluation of the history of each accident, with greater awareness of the potential of certain types of accidents to cause spinal cord injury, should reduce the incidence of missed injuries of the spinal cord.     

Under-exposure to official matches is associated with muscle injury incidence in professional footballers

External workload from matches is considered one of the most important muscle injury risk factors for football teams. However, there is scarce published evidence to support this belief. This study examined whether a particular profile of external match workload existed prior to a muscle injury. A total of 144 professional football players belonging to 2 teams were monitored over three seasons. For each muscle injury, a profile of external workload variables was determined for 5 to 8 games and expressed as: time playing exposure, total distance (TD) covered and high-speed running (HSR) covered. In addition, acute:chronic workload ratio (ACWR) was calculated. Sixty players (41.6%) reported a total of 86 muscle injuries during the three seasons. Muscle injuries occurred principally in matches (79.1%), the hamstring being the most affected muscle (44.1%). Injured players displayed substantially lower accumulated exposure time (ES = 0.45), TD (ES = 0.45) and HSR (ES = 0.39) in comparison with uninjured players in the last 5 games prior to injury. Compared to the uninjured players, ACWR for exposure (ES = -0.29/0.02) and running load (ES = -0.24/0.00) did not differ between match 5 and 2 prior to the injury, although uninjured players displayed a substantially greater ACWR in all 3 variables (ES = 0.31/0.35) than injured players in match 1 prior to the injury. Lower playing exposure (minutes played) and associated reduced running distances (TD and HSR) were observed in injured football players. Being under-loaded in official games could be a mediator for muscle injury in this cohort of elite football players.     

Autonomic dysreflexia during sperm retrieval in spinal cord injury: influence of lesion level and sildenafil citrate.

Autonomic dysreflexia (AD) can occur during penile vibratory stimulation in men with spinal cord injury, but this is variable, and the association with lesion level is unclear. The purpose of this study was to characterize the cardiovascular responses to penile vibratory stimulation in men with spinal cord injury. We hypothesized that those with cervical injuries would demonstrate a greater degree of AD compared with men with thoracic injuries. We also questioned whether the rise in blood pressure could be attenuated by sildenafil citrate. Participants were classified as having cervical (n = 8) or thoracic (n = 5) injuries. While in a supine position, subjects were instrumented with an ECG, and arterial blood pressure was determined beat by beat. Subjects reported to the laboratory twice and received an oral dose of sildenafil citrate (25-100 mg) or no medication. Penile vibratory stimulation was performed using a handheld vibrator to the point of ejaculation. At ejaculation during the nonmedicated trials, the cervical group had a significant decrease in heart rate (-5-10 beats/min) and increase in mean arterial blood pressure (+70-90 mmHg) relative to resting conditions, whereas the thoracic group had significant increases in both heart rate (+8-15 beats/min) and mean arterial pressure (+25-30 mmHg). Sildenafil citrate had no effect on the change in heart rate or mean arterial pressure in either group. In summary, men with cervical injuries had more pronounced AD during penile vibratory stimulation than men with thoracic injuries. Administration of sildenafil citrate had no effect on heart rate or blood pressure during penile vibratory stimulation in men with spinal cord injury.     

Epidemiology of Spinal Cord Injuries and Risk Factors for Complete Injuries in Guangdong,China: A Retrospective Study

Background

Spinal cord injuries are highly disabling and deadly injuries. Currently, few studies focus on non-traumatic spinal cord injuries, and there is little information regarding the risk factors for complete injuries. This study aims to describe the demographics and the injury characteristics for both traumatic and non-traumatic spinal cord injuries and to explore the risk factors for complete spinal cord injuries.

Methods

A retrospective study was performed by reviewing the medical records of 3,832 patients with spinal cord injuries who were first admitted to the sampled hospitals in Guangdong, China. The demographics and injury characteristics of the patients were described and compared between the different groups using the chi-square test. Logistic regression was conducted to analyze the risk factors for complete spinal cord injuries.

Results

The proportion of patients increased from 7.0% to 14.0% from 2003 to 2011. The male-to-female ratio was 3.0∶1. The major cause of spinal cord injuries was traffic accidents (21.7%). Many of the injured were workers (36.2%), peasants (22.8%), and unemployed people (13.9%); these occupations accounted for 72.9% of the total sample. A multivariate logistic regression model revealed that the OR (95% CI) for male gender compared to female gender was 1.25 (1.07–1.89), the OR (95%CI) for having a spinal fracture was 1.56 (1.35–2.60), the OR (95%CI) for having a thoracic injury was 1.23 (1.10–2.00), and the OR (95%CI) for having complications was 2.47 (1.96–3.13).

Conclusion

The proportion of males was higher than the proportion of females. Workers, peasants and the unemployed comprised the high-risk occupational categories. Male gender, having a spinal fracture, having a thoracic injury, and having complications were the major risk factors for a complete injury. We recommend that preventive measures should focus on high-risk populations, such as young males.