The Interaction of Intramuscular Ketorolac (Toradol) and Concussion in a Rat Model

Repetitive mild TBI causes pTau aggregation in nigra without altering preexisting fibril induced Parkinson's-like pathology burden

Population studies have shown that traumatic brain injury (TBI) is associated with an increased risk for Parkinson's disease (PD) and among U.S. Veterans with a history of TBI this risk is 56% higher. The most common type of TBI is mild (mTBI) and often occurs repeatedly among athletes, military personnel, and victims of domestic violence. PD is classically characterized by deficits in fine motor movement control resulting from progressive neurodegeneration of dopaminergic neurons in the substantia nigra pars compacta (SNpc) midbrain region. This neurodegeneration is preceded by the predictable spread of characteristic alpha synuclein (αSyn) protein inclusions. Whether repetitive mTBI (r-mTBI) can nucleate PD pathology or accelerate prodromal PD pathology remains unknown. To answer this question, an injury device was constructed to deliver a surgery-free r-mTBI to rats and human-like PD pathology was induced by intracranial injection of recombinant αSyn preformed fibrils. At the 3-month endpoint, the r-mTBI caused encephalomalacia throughout the brain reminiscent of neuroimaging findings in patients with a history of mTBI, accompanied by astrocyte expansion and microglial activation. The pathology associated most closely with PD, which includes dopaminergic neurodegeneration in the SNpc and Lewy body-like αSyn inclusion burden in the surviving neurons, was not produced de novo by r-mTBI nor was the fibril induced preexisting pathology accelerated. r-mTBI did however cause aggregation of phosphorylated Tau (pTau) protein in nigra of rats with and without preexisting PD-like pathology. pTau aggregation was also found to colocalize with PFF induced αSyn pathology without r-mTBI. These findings suggest that r-mTBI induced pTau aggregate deposition in dopaminergic neurons may create an environment conducive to αSyn pathology nucleation and may add to preexisting proteinaceous aggregate burden.

Analgesia in Athletes: A Review of Commonly Used Oral and Injectable Modalities

Pain is common among athletes at all levels and the treatment of pain can be a challenging and frustrating task. The team physician needs a fundamental knowledge of analgesic strategies as it relates to athletes. It is important to understand the mechanism of action, side effect profile/associated complications, incidence of and indications for use, as well as the controversies associated with the most common analgesic medications used in sports medicine. Several "in vogue" treatment modalities, including cannabidiol, are also becoming more commonly used and are worth discussion.

Evaluation of Inflammatory Response Due to Use of Controlled Release Drug Delivery System of Chitosan Hydrogel Loaded with Buprenorphine and Ketorolac in Rat with Experimental Proximal Tibial Epiphysis Defect

Aims:A controlled release drug delivery system loaded with buprenorphine and ketorolac was synthesized and used in the experimental model of bone defect and while evaluating the inflammatory response, the repair process in the defects was investigated.Materials and methods:To determine the effectiveness of the synthesized the mentioned systems, 5 groups were defined; the control group, the chitosan hydrogel receiving group (chitosan group), the ketorolac-loaded chitosan hydrogel group (ketorolac group), the buprenorphine-loaded chitosan hydrogel receiving group (buprenorphine group), and the chitosan hydrogel-loading group loaded with a combination of ketorolac and buprenorphine (ketorolac-buprenorphine group).Results:The results showed that the population of leukocytes (tWBC) and neutrophils on different days of the study in the control group compared to other groups had a significant increase (P < 0.05) while on day 7 of the study in the ketorolac group these parameters decreased significantly compared to other groups (P < 0.05). While examining the histological changes in the experimental defect created in the proximal tibia of rats at different times, some inflammatory indices such as total and differential leukocyte population, plasma concentrations of TNF-α and IL-6 were compared in different groups (P < 0.05). The various evaluated data showed that among the different groups, in the control and ketorolac-buprenorphine groups, there was the lowest and highest control of inflammatory response and bone repair, respectively.Conclusion:In the ketorolac group due to the impact of ketorolac on leukocyte populations the best bone healing can be expected among the different treatment groups.

Nonsteroidal anti-inflammatory drug use and concussions in adolescent athletes: incidence, severity, and recovery

OBJECTIVE

Given concerns about the potential long-term effects of concussion in young athletes, concussion prevention has become a major focus for amateur sports leagues. Athletes have been known to frequently use anti-inflammatory medications to manage injuries, expedite return to play, and treat concussion symptoms. However, the effects of baseline nonsteroidal anti-inflammatory drug (NSAID) use on the susceptibility to head injury and concussion remain unclear. This study aims to assess the effects of preinjury NSAID use on concussion incidence, severity, and recovery in young athletes.

METHODS

Data from 25,815 ImPACT (Immediate Post-Concussion Assessment and Cognitive Testing) tests were obtained through a research agreement with ImPACT Applications Inc. Subjects ranged in age from 12 to 22 years old. Those who reported NSAID use at baseline were assigned to one (anti-inflammatory [AI]) cohort, whereas all others were assigned to the control (CT) cohort. Differences in head trauma and concussion incidence, severity, and recovery were assessed using chi-square tests, unpaired t-tests, and Kaplan-Meier plots.

RESULTS

The CT cohort comprised a higher percentage (p < 0.0001) of males (66.30%) than the AI cohort (44.16%) and had a significantly greater portion of athletes who played football (p = 0.004). However, no statistically significant differences were found between the two cohorts in terms of the incidence of head trauma (CT = 0.489, AI = 0.500, p = 0.9219), concussion incidence (CT = 0.175, AI = 0.169, p = 0.7201), injury severity, or median concussion recovery time (CT = 8, AI = 8, p = 0.6416). In a multivariable analysis controlling for baseline differences between the cohorts, no association was found between NSAID use and concussion incidence or severity.

CONCLUSIONS

In this analysis, the authors found no evidence that preinjury use of NSAIDs affects concussion risk in adolescent athletes. They also found no indication that preinjury NSAID use affects the severity of initial injury presentation or concussion recovery.

Mild Traumatic Brain Injury in Children

Mild traumatic brain injury accounts for an estimated 4.8 million cases of pediatric traumatic brain injuries worldwide every year. In the United States, 70% of mild traumatic brain injury cases are due to sports and recreational injuries. Early diagnosis, especially in active children, is critical to preventing recurrent injuries. Management is guided by graded protocols for returning to school and activity. Ninety percent of children recover within 1 month of injury. Promising research has shown that early referral to specialty concussion care and multidisciplinary treatment with physical and occupational therapy may shorten recovery time and improve neurologic outcomes.

A Systematic Review of Closed Head Injury Models of Mild Traumatic Brain Injury in Mice and Rats

Mild TBI (mTBI) is a significant health concern. Animal models of mTBI are essential for understanding mechanisms, and pathological outcomes, as well as to test therapeutic interventions. A variety of closed head models of mTBI that incorporate different aspects (i.e., biomechanics) of the mTBI have been reported. The aim of the current review was to compile a comprehensive list of the closed head mTBI rodent models, along with the common data elements, and outcomes, with the goal to summarize the current state of the field. Publications were identified from a search of PubMed and Web of Science and screened for eligibility following PRISMA guidelines. Articles were included that were closed head injuries in which the authors classified the injury as mild in rats or mice. Injury model and animal-specific common data elements, as well as behavioral and histological outcomes, were collected and compiled from a total of 402 articles. Our results outline the wide variety of methods used to model mTBI. We also discovered that female rodents and both young and aged animals are under-represented in experimental mTBI studies. Our findings will aid in providing context comparing the injury models and provide a starting point for the selection of the most appropriate model of mTBI to address a specific hypothesis. We believe this review will be a useful starting place for determining what has been done and what knowledge is missing in the field to reduce the burden of mTBI.