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Background: Cephalohematomas (CH) are benign neonatal fluid collections that arise between the periosteum and skull due to birth trauma, and usually resolve spontaneously without intervention. CH may rarely become infected. Case Description: The authors report a case of sterile CH requiring surgical evacuation in a persistently febrile neonate treated with intravenous (IV) antibiotics for Escherichia coli urosepsis. Diagnostic tap of the CH yielded no pathogens, but given the persistence of fevers, surgical evacuation was performed. The patient demonstrated clinical improvement postoperatively. Conclusion: A systematic review of literature was conducted through a MEDLINE search using the keyword “cephalohematoma.” Articles were screened for cases of infected CH and their subsequent management. Clinicopathological characteristics and outcomes of the present case were reviewed and compared to those in the literature. Infected CH were reported in 25 articles describing 58 patients. Common pathogens included E. coli and Staphylococcal species. Treatment included a course of IV antibiotics (10 days–6 weeks) and often included percutaneous aspiration (n = 47) for diagnostic and therapeutic purposes. Surgical evacuation was performed in 23 cases. To the authors’ knowledge, the present case is the first documented report in which evacuation of a culture-negative CH resulted in resolution of the patient’s clinical symptoms of sepsis that persisted despite appropriate antibiotic treatment. This suggests that patients with CH should be evaluated through diagnostic tap of the collection if there are signs of local or persistent systemic infection. Surgical evacuation may be indicated if percutaneous aspiration does not result in clinical improvement.

The theoretical advantages of hybrid constructs over multi-level fusion have been illustrated in clinical and biomechanical studies. However, there is no biomechanical data on hybrid constructs using load control analyses. There is also no clear data on whether there is a biomechanical difference if the arthroplasty is below or above a 1- or 2-level fusion. This work investigated the effect on segmental motion of having a cervical total disc arthroplasty implanted above or below a 1- or 2-level fusion.Segmental motions of 16 C2-T1 cervical spine specimens were measured as the specimens were tested to 1.5Nm in axial rotation and in flexion-extension under compressive preload. Tests were conducted on intact specimens, and then after arthroplasty with a 1-level and 2-level fusion. 8 specimens were in test Group 1, where the hybrid configuration had a total disc arthroplasty above a 1- or 2-level fusion. The arthroplasty was below the 1- and 2-level fusion in Group 2. Load control and displacement control analyses were conducted to determine the effect of the hybrid configurations on segmental motion.In load control, compensatory motion increases were found at all non-instrumented cervical spine segments in flexion-extension and axial rotation. Flexion-extension and axial rotation ranges of motion at the total disc arthroplasty level were less than 1° different than intact.In displacement control, there was no consistent pattern of compensatory motion. Range of motion at the arthroplasty level was within 3.5° of intact.The total disc arthroplasty segmental level in a hybrid construct has similar amounts of motion as intact. This may shield the arthroplasty level and adjacent levels from supra-physiological motion and loading. These results suggest that a hybrid construct may be protective of adjacent segments, whether the total disc arthroplasty is above or below the fusion.

BACKGROUND CONTEXT Elderly patients are increasingly meeting the indications for spinal fusion and are more likely to have suboptimal bone quality. Patients with suboptimal bone quality who have undergone posterior cervical fusion have increased risk of fixation failure of up to 5.4% and may require stronger forms of fixation. Adding supplemental fixation to lateral mass screws (LMS) can increase fixation as measured by pullout strength. PURPOSE This work addresses the question: can supplemental screw fixation of lateral mass screws improve pullout strength? STUDY DESIGN/SETTING Biomechanical cadaveric study. PATIENT SAMPLE Fifteen C3-C6 vertebral bodies and 15 additional motion segments (C3-C4 or C5-C6) (age: 49-67). OUTCOME MEASURES Lateral mass screw construct peak pullout strength. METHODS All specimens were CT scanned with a phantom to obtain bone mineral density (BMD). The individual vertebral bodies and the cranial body of the motion segments were implanted with bilateral lateral mass screws. Supplemental fixation was added on one side of the vertebral body using two 2.4mm diameter unicortical screws (length 8-12mm). One side of the cranial vertebral body of the motion segments was supplemented with a single 2.4mm diameter transfacet tricortical screw (length 12-16mm). Screw constructs were subjected to posterior pullout coincident with the axis of the lateral mass screw at a rate of 5mm/min until failure. RESULTS A paired comparison was made of the peak pullout force of the LMS alone and LMS with supplemental fixation. Analysis was also made comparing BMD and pullout force.In the vertebral bodies with two supplemental unicortical screws, pullout force was significantly higher in the supplemented screw side. The average pullout force was 48.2% higher with supplemental screws (865±213N vs 637±206N; p=0.0038). There was moderate correlation between pullout force and bone mineral density for both the supplemented and LMS alone (correlation coefficients of 0.34 and 0.45 respectively). In the motion segments, peak pullout force was significantly higher in the side supplemented with a tricortical transfacet screw. The pullout force was 25.9% higher with supplemental transfacet screw fixation (1055±521N vs 912±508N; p=0.047). The pullout strength of the LMS with transfacet fixation was highly correlated with BMD (correlation coefficient of 0.71) while the LMS pullout strength was moderately correlated with BMD (correlation coefficient of 0.64). CONCLUSIONS Our data confirms the hypotheses that the pullout strength of C3-C6 LMS fixation using LMS supplemented with two unicortical screws or LMS supplemented with one-tricortical transfacet screw is superior to LMS fixation alone. FDA DEVICE/DRUG STATUS Cervical Fusion System (Approved for this indication)

BACKGROUND CONTEXT The use of cervical disc arthroplasty (CDA) adjacent to an anterior cervical decompression and fusion (ACDF), a hybrid construct, is an attractive alternative to a multilevel cervical fusion operation. Consider a clinical scenario where a patient with a prior fusion at C6-C7 develops new radiculopathy and/or myelopathy at C5-C6. A surgeon considers a CDA at C5-C6, proximal to an existing C6-C7 ACDF, in hopes of reducing the risk of adjacent segment disease at C4-C5. Another clinical scenario is in the presence of two symptomatic adjacent cervical segments, a surgeon may consider fusing the segment with more severe spondylotic changes such as severe disc collapse and facet arthropathy while performing CDA at the adjacent, more mobile segment. While numerous studies have demonstrated excellent clinical outcomes of primary cervical disc replacement surgery, many questions regarding the biomechanics of CDA in a hybrid construct remain unanswered. PURPOSE (1) How is disc prosthesis motion response influenced by the presence of a fusion proximal or distal to the prosthesis? and (2) How does the number of fused levels in the hybrid construct affect the prosthesis motion? STUDY DESIGN/SETTING Biomechanical study using human cadaveric cervical spines. PATIENT SAMPLE Human cervical spine specimens (C2-T1, N=10, 46±16 years). OUTCOME MEASURES Segmental flexion-extension range of motion (ROM). METHODS Specimens were divided into two equal groups based on age, gender distribution, and preoperative mobility. Segmental motions were assessed under flexion and extension moments of 1.5 Newton-meters. In Group I, the arthroplasty was proximal to one- and two-level ACDF, while in Group 2, the arthroplasty was distal to one- and two-level ACDF. ACDF was performed using a PEEK cage and anterior plate and CDA was performed using the M6-C cervical disc prosthesis (Orthofix Medical, Inc). Within group comparisons were made using a repeated-measures ANOVA and paired-t test, whereas across group comparisons used 2-sample t-test. RESULTS Segment level of implantation: 20 segments underwent CDA. Ten discs were implanted at C4-C5, 5 at C5-C6, and 5 at C6-C7. The mean segmental ROM after CDA was 9.2±4.2 degrees. Segmental level of implantation did not influence the ROM (C4-C5: 8.6±3.7; C5-C6: 9.4±4.1; C6-C7: 10.0±6.1; p>0.7). Number of fused levels in the hybrid construct: The number of fused segments in the hybrid construct did not influence the ROM after CDA (1-level: 9.7±4.6 vs 2-level: 9.9±4.4; p=0.9). CDA proximal vs distal to fusion: CDA above a 1-level ACDF had ROM similar to CDA below a 1-level ACDF (9.4±4.1 degrees vs 10.0±6.1; p=0.76). This result also held for a prosthesis implanted above versus below a 2-level ACDF (9.9±4.6 vs 9.8±5.2; p=1.0). CDA in hybrid construct compared to intact: CDA in a hybrid construct had ROM similar to the ROM of the corresponding segment in the intact spine. This result held true for all hybrid constructs studied regardless of location of prosthesis above or below a fusion, and the number of fused levels. CONCLUSIONS This study simulated a scenario where the patient experiences the same moments before and after surgery. Some authors suggest patients maintain similar ROM before and after surgery. Likely, actual in vivo loading reflects a combination of the two approaches. Results of this study suggest that disc arthroplasty performed adjacent to a 1- or 2-level cervical fusion is likely to maintain the same degree of motion as a primary arthroplasty. These findings provide a cadaveric basis for future in vivo studies to validate these results. FDA DEVICE/DRUG STATUS M6C artificial cervical disc, Orthofix, Inc (Not approved for this indication)

INTRODUCTION Morphologic features of computed tomography (CT) scans of the brain can be used to estimate intracranial pressure (ICP) via an image-processing algorithm. Clinically, such estimations can be used to prognosticate outcomes and avoid placement of invasive intracranial monitors in certain patients with severe traumatic brain injury. Features on a CT scan that may correlate with measurements of low ICP are sought. METHODS A measure is proposed that is a function of the distribution of cerebrospinal fluid (CSF) in and around the brain. In our method, we present an algorithm that semiautomatically segments brain parenchyma from CSF, and apply standard image processing calculations. The ratio of CSF volume to the size of the intracranial vault (ICV) or volume inside the skull, csf(v) /icv(v) is calculated and then plotted against the actual recorded ICP, yielding a relationship between the image features and ICP. RESULTS We analyzed a total of 45 scans from 20 patients with severe traumatic brain injury (TBI). We showed that a ratio csf(v)/icv(v) > .034 correlates with an ICP < 20 mmHg (P = .0046). For csf(v)/icv(v) ≤ .034, a distinction between low and high ICP cannot be effectively estimated by this univariate measure. CONCLUSION This method permits a noninvasive means of identifying patients who are low risk for having elevated ICP; by following Brain Trauma Foundation guidelines strictly such a patient may be subjected to an unnecessary, invasive procedure. This work is a promising pilot study that will need to be analyzed for a larger population.

Objective The authors report a case of a large intracerebellar hemorrhage that occurred in a professional musician while playing the trumpet. This is the first report of such a complication. Clinical presentation A 60-year-old man presented with severe occipital headache accompanied by nausea, vomiting, and dizziness that occurred while he was practicing the trumpet. On presentation, he was hypertensive with a systolic blood pressure of 255 mmHg and was found to have a large left cerebellar hemorrhage. Intervention Magnetic resonance imaging and magnetic resonance angiography were performed but revealed no tumor or vascular abnormality. The patient was initially stable but, despite maximal medical therapy, deteriorated and was taken to the operating room for suboccipital craniectomy and evacuation of the hematoma. Conclusion This patient likely had chronic hypertension; however, the transient increase in systolic blood pressure associated with intensive trumpet playing and the Valsalva maneuver may have contributed to his risk of hemorrhage. We suggest that hypertensive screening and therapy may be especially important in this population and emphasize the importance for neurosurgeons to understand the physiology involved in the Valsalva maneuver.