Lemierre Disease: A Case With Multilevel Epidural Abscess and Aggressive Neurological Weakness: Case Report and Literature Review.

BACKGROUND: Lemierre disease is a rare postanginal sepsis caused by the anaerobe Fusobacterium necrophorum. It is associated with a pharyngitis that progresses quickly to thrombophlebitis of the internal jugular vein and metastatic abscesses to pulmonary, soft tissue, articular, and organ systems. It is rarely associated with spinal epidural abscesses. Because of the increasing antibiotic resistance, its incidence is on the rise. METHODS: A single-patient case report of an adolescent male who initially presented to our institution for bacteremia and febrile episodes. Over a 1-week course, he developed severe back pain and progressive lower extremity weakness. Advanced imaging revealed an epidural abscess spanning T2-L3 level with extension into the psoas and the paraspinal musculature. Acute management consisted of broad-spectrum intravenous (IV) antibiotics and hemilaminectomy decompression from T2 to L3. The patient completed a 6-week course of IV antibiotics and was followed for a 1-year time period with close clinical follow-up. RESULTS: Blood cultures identified the infecting organism as F. necrophorum. The combination of IV antibiotics and acute hemilaminectomy decompression resulted in successful clearance of the infecting organism with normalization of inflammatory markers and cultures. The patient noted immediate and sustained neurological improvement, with return of full motor and sensory function. At the 1-year timepoint, the patient was able to return to sports and no sagittal/coronal imbalance was noted on radiographs. CONCLUSIONS: An aggressive case of Lemierre disease with extensive epidural abscess formation and neurological weakness was successfully managed with the combination of IV antibiotics and extensive hemilaminectomies for decompression. The patient exhibited no long-term sequela as a result of either the epidural abscess or of its treatment. LEVEL OF EVIDENCE: Level V.

Biomechanical Contribution of Tension-Reducing Rotator Cuff Sutures in 3-Part Proximal Humerus Fractures.

OBJECTIVES: Using a cadaveric 3-part fracture model and cyclic loading protocol, our study objectives were to quantify the stabilizing effect of tension-reducing rotator cuff sutures in terms of fracture displacement across the surgical neck and greater tuberosity compared with a control group in which no sutures were used. METHODS: Six matched pairs of fresh frozen specimens underwent a standardized, 3-part, proximal humerus fracture and were split into 2 groups. The control group had the fracture fixed with a plate and screw construct only while the experimental group had additional suture fixation through the plate to each rotator cuff tendon. Active abduction through the rotator cuff was simulated for 100, 200, 300, and 400 cycles and to failure at 1000 N. A Mann-Whitney U test compared cyclic displacement of the greater tuberosity and surgical neck fracture gaps and load to failure between the 2 groups. RESULTS: There was no significant difference (P > 0.05) in fracture gap between fixation methods at the surgical neck at 100 (P = 0.13), 200 (P = 0.07), 300 (P = 0.49), and 400 (P = 0.07) cycles. There was no significant difference (P > 0.05) between fixation methods in the fracture gap at the greater tuberosity at 100 (P = 0.39), 200 (P = 1.00), 300 (P = 0.31), and 400 (P = 0.59) cycles. There was no significant difference (P > 0.5) at 1000 N at the surgical neck (P = 0.70) or the greater tuberosity (P = 0.39). CONCLUSIONS: Tension-relieving rotator cuff sutures do not add stability to the repair of 3-part proximal humerus fractures. Varus collapse and greater tuberosity displacement are common complications associated with 3-part fractures. No mechanical data exist to demonstrate benefit of adding suture to a plate and screw construct for limiting fracture displacement.

CT-generated radiographs in obese patients with acetabular fractures: can they be used in lieu of plain radiographs?

BACKGROUND: Acetabular fracture diagnosis is traditionally made with AP and oblique pelvic plain radiographs. Obesity may impair diagnostic accuracy of plain radiographs. New CT reconstruction algorithms allow for simulated radiographs that may eliminate the adverse imaging effects of obesity. QUESTIONS/PURPOSES: In obese patients with acetabular fractures, we compared CT-generated and plain radiographs in terms of (1) ability to classify fracture type, (2) agreement in fracture classification, and (3) surgeon performance at different experience levels. METHODS: CT-generated and plain radiograph image sets were created for 16 obese (BMI>35) patients with 17 acetabular fractures presenting from 2009 to 2011. Three orthopaedic trauma attending physicians, three senior residents, and three junior residents independently viewed these sets and recorded their diagnoses. These diagnoses were compared to the postoperative findings, which we defined as the gold standard for diagnosis. To assess intraobserver reliability, the same observers reviewed a rerandomized set 1 month later. We had 80% power to detect a 25% difference in the percentage of correctly classified fractures based on a post hoc sample size calculation and 80% power to detect a 0.10 difference in κ value based on both a priori and post hoc sample size calculations. RESULTS: With the numbers available (153 observations in each image set, 51 for each of the three observer groups), we found no differences between CT-generated and plain radiographs, respectively, in terms of percentage of correct diagnoses for the observer groups (all observers: 54% versus 49%, p=0.48; attendings: 61% versus 59%, p=0.83; senior residents: 51% versus 53%, p=0.84; and junior residents: 49% versus 35%, p=0.16). Furthermore, agreement between CT-generated and plain radiographic fracture classifications was substantial (κ=0.67). Nonetheless, the attending and senior resident groups performed better in correctly classifying the fracture than the junior residents when using plain radiographs (p=0.01 and p=0.049, respectively). Performance was not different when comparing the attendings to the senior resident and junior groups or comparing the senior residents to the junior residents using CT-generated radiographs (p=0.32, p=0.22, and p=0.83, respectively). CONCLUSIONS: CT-generated radiographs are as good as plain radiographs for experienced surgeons for classifying acetabular fractures in obese patients. CT-generated imaging may be valuable in both teaching and clinical settings, and it may spare the patient additional radiation exposure and discomfort. LEVEL OF EVIDENCE: Level II, diagnostic study. See the Instructions for Authors for a complete description of levels of evidence.

No Contribution of Tension-Reducing Rotator Cuff Sutures on Locking Plate Fixation in a 2-Part Proximal Humerus Fracture Model.

OBJECTIVES: Varus failure is a well-known complication of open reduction internal fixation of proximal humeral fractures. The addition of tension-reducing sutures from the plate to the rotator cuff may attenuate the deforming forces of the rotator cuff resulting in decreased varus failure. In this study, we investigate the biomechanical contributions of tension-reducing sutures to a locked plate construct in a 2-part proximal humerus fracture model. METHODS: Two fixation techniques were tested in 12 matched fresh frozen humeri in which standard 2-part fractures of the surgical neck were created with a gap simulating surgical neck medial comminution. In group 1, fractures were fixed with a standard proximal humerus locking plate. In group 2, the plate fixation was similar, and additionally, tension-reducing sutures were applied from the plate to the rotator cuff. Active abduction was simulated for 400 cycles with force applied through the rotator cuff tendons. Intercyclic fracture motion, change in displacement, and load to failure were recorded. RESULTS: The addition of tension-reducing sutures did not lead to significant differences in intercyclic fracture motion. The mean change in displacement and load to failure were similar in both groups. Failure typically occurred in both groups at the rotator cuff testing clamp interface. CONCLUSIONS: Tension-relieving rotator cuff sutures added to locking plate fixation did not lead to a change in fracture gap with cyclic loading or an increase in ultimate failure load in a 2-part surgical neck proximal humerus fracture model without medial support.

Kainate seizures cause acute dendritic injury and actin depolymerization in vivo.

Seizures may cause brain injury via a variety of mechanisms, potentially contributing to cognitive deficits in epilepsy patients. Although seizures induce neuronal death in some situations, they may also have "nonlethal" pathophysiological effects on neuronal structure and function, such as modifying dendritic morphology. Previous studies involving conventional fixed tissue analysis have demonstrated a chronic loss of dendritic spines after seizures in animal models and human tissue. More recently, in vivo time-lapse imaging methods have been used to monitor acute changes in spines directly during seizures, but documented spine loss only under severe conditions. Here, we examined effects of secondary generalized seizures induced by kainate, on dendritic structure of neocortical neurons using multiphoton imaging in live mice in vivo and investigated molecular mechanisms mediating these structural changes. Higher-stage kainate-induced seizures caused dramatic dendritic beading and loss of spines within minutes, in the absence of neuronal death or changes in systemic oxygenation. Although the dendritic beading improved rapidly after the seizures, the spine loss recovered only partially over a 24 h period. Kainate seizures also resulted in activation of the actin-depolymerizing factor, cofilin, and a corresponding decrease in filamentous actin, indicating that depolymerization of actin may mediate the morphological dendritic changes. Finally, an inhibitor of the calcium-dependent phosphatase, calcineurin, antagonized the effects of seizures on cofilin activation and spine morphology. These dramatic in vivo findings demonstrate that seizures produce acute dendritic injury in neocortical neurons via calcineurin-dependent regulation of the actin cytoskeleton, suggesting novel therapeutic targets for preventing seizure-induced brain injury.