Keywords:total hip arthroplasty nerve injury risk factors age tobacco spine disease a b s t r a c t Background: Postsurgical acute nerve injury is rare but potentially devastating following total hip arthroplasty (THA). Previous literature suggests a wide range of incidence from 0.1% to 7.6%. Confirmed risk factors for these injuries remain unclear. Methods: THA patients at our institution who developed nerve injury during their admission for THA between January 1, 1998, and December 31, 2013, were systematically identified and matched with 2 control subjects by surgical date. Relevant patient and surgical data were obtained through review of patient charts and electronic health records. We identified potential risk factors and calculated odds ratios (OR) using a conditional logistic regression model with a parsimonious stepwise approach. Results: We identified 93 nerve injuries in 43,761 THAs (0.21%). The mean age of cases was 63 years. Adjusting for other factors in the model, patients <45 years were found to be at increased risk of developing nerve injury (OR, 7.17; P ¼ .033). Similarly, patients with a history of tobacco use (OR, 1.90; P ¼ .030) and a history of spinal surgery or disease (OR, 10.06; P < .001) were also associated with increased risk of nerve injury. For every 30-minute increase in surgery time after 1 hour, risk of nerve injury risk increased (OR, 1.48; P ¼ .034). Assignment as first operative case of the morning was associated with a decreased risk of nerve injury (OR, 0.37, P ¼ .043). Conclusion: This study demonstrates that nerve injury is a rare complication following THA at our institution. We found risk factors that are possibly modifiable factors such as lumbar spine disease, smoking, and time of surgical scheduling.

Background: Uncertainty continues to surround mild traumatic brain injury (mTBI) diagnosis, symptoms, prognosis, and outcome due in part to a lack of objective biomarkers of injury and recovery. As mTBI gains recognition as a serious public health epidemic, there is need to identify risk factors, diagnostic tools, and imaging biomarkers to help guide diagnosis and management.Methods: One hundred and eleven patients (15–50 years old) were enrolled acutely after mTBI and followed with up to four standardized serial assessments over 3 months. Each encounter included a clinical exam, neuropsychological assessment, and magnetic resonance imaging (MRI). Chi-square and linear mixed models were used to assess changes over time and determine potential biomarkers of mTBI severity and outcome.Results: The symptoms most frequently endorsed after mTBI were headache (91%), not feeling right (89%), fatigue (86%), and feeling slowed down (84%). Of the 104 mTBI patients with a processed MRI scan, 28 (27%) subjects had white matter changes which were deemed unrelated to age, and 26 of these findings were deemed unrelated to acute trauma. Of the neuropsychological assessments tested, 5- and 6-Digit Backward Recall, the modified Balance Error Scoring System (BESS), and Immediate 5-Word Recall significantly improved longitudinally in mTBI subjects and differentiated between mTBI subjects and controls. Female sex was found to increase symptom severity scores (SSS) at every time point. Age ≥ 25 years was correlated with increased SSS. Subjects aged ≥ 25 also did not improve longitudinally on 5-Digit Backward Recall, Immediate 5-Word Recall, or Single-Leg Stance of the BESS, whereas subjects < 25 years improved significantly. Patients who reported personal history of depression, anxiety, or other psychiatric disorder had higher SSS at each time point.Conclusions: The results of this study show that 5- and 6-Digit Backward Recall, the modified BESS, and Immediate 5-Word Recall should be considered useful in demonstrating cognitive and vestibular improvement during the mTBI recovery process. Clinicians should take female sex, older age, and history of psychiatric disorder into account when managing mTBI patients. Further study is necessary to determine the true prevalence of white matter changes in people with mTBI.

Few studies have investigated transient global amnesia (TGA) in the context of a concussion and the concussion sequelae following TGA. Here we review the case of a 43-year-old male with onset of transient global anterograde and retrograde amnesia 22 days after a sustained concussion. The patient's head CT, MRI of brain, and EEG were reported normal, and the patient regained full cognitive function 8 h after the TGA episode, with no recollection of the conspiring events. Following the TGA episode, the patient experienced notable worsening of concussive symptoms, including headache, head pressure, anxiety, neck pain, feeling slowed down, fogginess, not feeling right, difficulty remembering, and fatigue. The patient remained symptomatic for 32 days after the TGA episode. We suggest that a lingering window of post-concussion cerebral vulnerability, which may extend beyond clinical recovery, could lead to increased susceptibility to acute cognitive deficits, such as TGA.