Effects of Recent Concussion on Brain Bioenergetics: A Phosphorus-31 Magnetic Resonance Spectroscopy Study.

BACKGROUND: Although clinical evaluations and neurocognitive assessments are commonly used to evaluate the extent of and recovery from concussion, brain bioenergetics could provide a more quantitative marker. The neurometabolic response to a concussion is thought to increase neuronal energy consumption and thus the demand for nucleoside triphosphate (NTP). OBJECTIVE: We investigated the possible disruption in high-energy metabolism within the prefrontal cortex of college athletes who had either had a concussion within the past 6 months (n=14) or had never had a concussion (n=13). We hypothesized that concussed athletes would have imbalanced brain bioenergetics resulting from increased NTP consumption, and these biochemical changes would correspond to impaired cognitive abilities. METHODS: We used phosphorus-31 magnetic resonance spectroscopy to quantify high-energy phosphates. We performed the neuroimaging in conjunction with neurocognitive assessments targeting prefrontal cortex-mediated tasks. RESULTS: Our results revealed significantly lower γ-NTP levels in the athletes after concussion. Although the concussed and non-concussed participants performed similarly in neurocognitive assessments, lower levels of γ-NTP were associated with worse scores on neurocognitive tasks. CONCLUSIONS: Our results support the concept of increased energy demand in the prefrontal cortex of a concussed brain, and we found that while neurocognitive assessments appear normal, brain energetics may be abnormal. A longitudinal study could help establish brain NTP levels as a biomarker to aid in diagnosis and to assess recovery in concussed patients.

Assessing the effectiveness of neuromuscular training programs in reducing the incidence of anterior cruciate ligament injuries in female athletes: a systematic review.

BACKGROUND: Anterior cruciate ligament (ACL) injuries are more common in female athletes because of anatomic and biomechanical factors. These injuries can have detrimental ramifications for the athlete and the health care system. Neuromuscular training programs have been designed to modify risk factors and prevent ACL injuries. PURPOSE: This systematic review evaluates studies that assess the effectiveness of neuromuscular training programs in reducing ACL injuries in female athletes and provides an update to 2 previously published reviews. STUDY DESIGN: Systematic review. METHODS: Medline, Cochrane, and CINAHL databases were searched for relevant journal articles published from 1995 to 2011. We performed a manual review of relevant articles, authors, and journals, including bibliographies from identified articles. Ten studies were included in this review. RESULTS: Only 2 studies demonstrated a statistically significant decrease in ACL injuries with neuromuscular training programs. Two additional studies showed a statistically significant decrease in subgroup analyses only. Four studies did show a trend toward reduced ACL injuries with neuromuscular training programs but were unable to achieve statistical significance. Neuromuscular training programs utilizing plyometric exercises and a preseason component were the most beneficial. Two studies actually showed an increase in injuries with intervention programs. CONCLUSION: Neuromuscular training programs may be a useful adjunct to training, but current literature precludes our universal recommendation of them.

A resting state functional magnetic resonance imaging study of concussion in collegiate athletes.

Sports-related concussions are currently diagnosed through multi-domain assessment by a medical professional and may utilize neurocognitive testing as an aid. However, these tests have only been able to detect differences in the days to week post-concussion. Here, we investigate a measure of brain function, namely resting state functional connectivity, which may detect residual brain differences in the weeks to months after concussion. Twenty-one student athletes (9 concussed within 6 months of enrollment; 12 non-concussed; between ages 18 and 22 years) were recruited for this study. All participants completed the Wisconsin Card Sorting Task and the Color-Word Interference Test. Neuroimaging data, specifically resting state functional Magnetic Resonance Imaging data, were acquired to examine resting state functional connectivity. Two sample t-tests were used to compare the neurocognitive scores and resting state functional connectivity patterns among concussed and non-concussed participants. Correlations between neurocognitive scores and resting state functional connectivity measures were also determined across all subjects. There were no significant differences in neurocognitive performance between concussed and non-concussed groups. Concussed subjects had significantly increased connections between areas of the brain that underlie executive function. Across all subjects, better neurocognitive performance corresponded to stronger brain connectivity. Even at rest, brains of concussed athletes may have to 'work harder' than their healthy peers to achieve similar neurocognitive results. Resting state brain connectivity may be able to detect prolonged brain differences in concussed athletes in a more quantitative manner than neurocognitive test scores.

Ear trauma.

Understanding basic ear anatomy and function allows an examiner to quickly and accurately identify at-risk structures in patients with head and ear trauma. External ear trauma (ie, hematoma or laceration) should be promptly treated with appropriate injury-specific techniques. Tympanic membrane injuries have multiple mechanisms and can often be conservatively treated. Temporal bone fractures are a common cause of ear trauma and can be life threatening. Facial nerve injuries and hearing loss can occur in ear trauma.

Chronic shoulder pain: part I. Evaluation and diagnosis.

Shoulder pain is defined as chronic when it has been present for longer than six months. Common conditions that can result in chronic shoulder pain include rotator cuff disorders, adhesive capsulitis, shoulder instability, and shoulder arthritis. Rotator cuff disorders include tendinopathy, partial tears, and complete tears. A clinical decision rule that is helpful in the diagnosis of rotator cuff tears includes pain with overhead activity, weakness on empty can and external rotation tests, and a positive impingement sign. Adhesive capsulitis can be associated with diabetes and thyroid disorders. Clinical presentation includes diffuse shoulder pain with restricted passive range of motion on examination. Acromioclavicular osteoarthritis presents with superior shoulder pain, acromioclavicular joint tenderness, and a painful cross-body adduction test. In patients who are older than 50 years, glenohumeral osteoarthritis usually presents as gradual pain and loss of motion. In patients younger than 40 years, glenohumeral instability generally presents with a history of dislocation or subluxation events. Positive apprehension and relocation are consistent with the diagnosis. Imaging studies, indicated when diagnosis remains unclear or management would be altered, include plain radiographs, magnetic resonance imaging, ultrasonography, and computed tomography scans. Plain radiographs may help diagnose massive rotator cuff tears, shoulder instability, and shoulder arthritis. Magnetic resonance imaging and ultrasonography are preferred for rotator cuff disorders. For shoulder instability, magnetic resonance imaging arthrogram is preferred over magnetic resonance imaging.

Chronic shoulder pain: part II. Treatment.

Chronic shoulder pain is a common problem in the primary care physician's office. Effective treatment depends on an accurate diagnosis of the more common etiologies: rotator cuff disorders, adhesive capsulitis, acromioclavicular osteoarthritis, glenohumeral osteoarthritis, and instability. Activity modification and analgesic medications comprise the initial treatment in most cases. If this does not lead to improvement, or if the initial presentation is of sufficient severity, a trial of physical therapy that focuses on the specific diagnosis is indicated. Combined steroid and local anesthetic injections can be used alone or as an adjuvant to the physical therapy. The site of the injection (subacromial, acromioclavicular joint, or intra-articular) depends on the diagnosis. Injections into the glenohumeral joint should be done under fluoroscopic guidance. Symptoms that persist or worsen after six to 12 weeks of directed treatment should be referred to an orthopedic specialist.