Percutaneous fixation of acetabular fractures: computer-assisted determination of safe zones, angles and lengths for screw insertion

Introduction

Percutaneous retrograde screw fixation for acetabular fractures is a demanding procedure due to the complex anatomy of the pelvis and the varying narrow safe bony corridors. Limited information is available on optimal screw placement and the geometry of safe zones for screw insertion in the pelvis.

Methods

Three-dimensional reconstructions of 50 consecutive CT scans of polytrauma patients (35 males, 15 females) were used to introduce three virtual CAD bolts (representing screws) into the anterior column (superior ramus of the pubic bone), posterior column (the ischial bone) and the supraacetabular region, as performed during percutaneous screw fixation. The three-dimensional (3D) position of these screws was evaluated with a computer software (MIMICS) after virtual optimal insertion. The 3D position, the narrowest zone and the distance to the hip joint of the two columns and the supraacetabular region were defined.

Results

The mean maximal screw length for the three virtual screws measured between 107.4 and 148?±?18.7?mm. The narrowest zone of the pelvic bone (superior pubic ramus) had a width of 9.2?±?2.4?mm. The average distances between the bolts and the hip joint were 3.9 and 19.4?±?7.4?mm. For the anterior column (superior pubic ramus) screw, the mean lateral angle to the sagittal midline plane was 39.0?±?3.2° and the mean posterior angle to the transversal midline plane was 15.1?±?4.0°. The mean supraacetabular screw angles measured 22.4?±?3.4° (medial), 35.3?±?4.6° (cranial) and the mean angles for the ischial screw were 12.0?±?5.4° (posterior) and 18.4?±?4.0° (lateral).

Conclusions

The zones for safe screw positioning are very narrow, making percutaneous screw fixation of the acetabulum a challenging procedure. The predefined angles for the most frequently positioned percutaneous screws may aid in preoperative planning, decrease operative and radiation times and help to increase safe insertion of screws.     

The role of shame in distinguishing perpetrators of intimate partner violence in U.S. veterans

Increasing attention is being paid to the fact that exposure to traumatic stressors in military combat may lead to perpetration of intimate partner violence (IPV). Because shame has been identified as a factor in posttraumatic stress disorder (PTSD), the current cross-sectional study examined the relationship in U.S. veterans between IPV and PTSD, depression, guilt, and shame. We hypothesized that shame would be the strongest correlate of perpetration of IPV and that shame would mediate the relationship between PTSD and IPV. Participants were 264 primarily male and Caucasian mixed-era veterans presenting for psychological treatment at a Veterans Affairs hospital. They completed standard measures of depression, PTSD symptoms, shame, and guilt and a local checklist was used to dichotomize the sample regarding IPV. Discriminant analysis indicated that shame contributed most (standardized canonical discriminant function coefficient = .44) to distinguishing perpetrators of IPV. In addition, the results were consistent with shame as a mediator of the relationship between PTSD and IPV. These results are in line with studies indicating that shame is linked to IPV perpetration in nonveteran samples (Harmon, 2002; Rand, 2004; Schibik, 2002) and suggests that shame may be an important aspect of the relationship between PTSD and IPV.     

Staged management of giant abdominal wall defects: acute and long-term results

INTRODUCTION: Shock resuscitation leads to visceral edema often precluding abdominal wall closure. We have developed a staged approach encompassing acute management through definitive abdominal wall reconstruction. The purpose of this report is to analyze our experience with this technique applied to the treatment of patients with open abdomen and giant abdominal wall defects. METHODS: Our management scheme for giant abdominal wall defects consists of 3 stages: stage I, absorbable mesh insertion for temporary closure (if edema quickly resolves within 3-5 days, the mesh is gradually pleated, allowing delayed fascial closure); stage II, absorbable mesh removal in patients without edema resolution (2-3 weeks after insertion to allow for granulation and fixation of viscera) and formation of the planned ventral hernia with either split thickness skin graft or full thickness skin closure over the viscera; and stage III, definitive reconstruction after 6-12 months (allowing for inflammation and dense adhesion resolution) by using the modified components separation technique. Consecutive patients from 1993 to 2001 at a single institution were evaluated. Outcomes were analyzed by management stage, with emphasis on wound related morbidity and mortality, and fistula and recurrent hernia rates. RESULTS: Two hundred seventy four patients (35 with sepsis, 239 with hemorrhagic shock) were managed. There were 212 males (77%), and mean age was 37 (range, 12-88). The average size of the defects was 20 x 30 cm. In the stage I group, 108 died (92% of all deaths) because of shock. The remaining 166 had temporary closure with polyglactin 910 woven absorbable mesh. As visceral edema resolved, bedside pleating of the absorbable mesh allowed delayed fascial closure in 37 patients (22%). In the stage II group, 9 died (8% of all deaths) from multiple organ failure associated with their underlying disease process, and 96% of the remaining 120 had split-thickness skin graft placed over the viscera. No wound related mortality occurred. There were a total of 14 fistulae (5% of total, 8% of survivors). In the stage III group, to date, 73 of the 120 have had definitive abdominal wall reconstruction using the modified components separation technique. There were no deaths. Mean follow-up was 24 months, (range 2-60). Recurrent hernias developed in 4 of these patients (5%). CONCLUSIONS: The staged management of patients with giant abdominal wall defects without the use of permanent mesh results in a safe and consistent approach for both initial and definitive management with low morbidity and no technique-related mortality. Absorbable mesh provides effective temporary abdominal wall defect coverage with a low fistula rate. Because of the low recurrent hernia rate and avoidance of permanent mesh, the components separation technique is the procedure of choice for definitive abdominal wall reconstruction.     

Associations among psychosis,mood, anxiety,and posttraumatic stress symptoms: A network analysis

The associations among psychotic experiences (i.e., hallucinations and delusions), trauma exposure, and posttraumatic stress symptoms are complex and multidirectional. Using network analysis to understand how psychotic experiences and symptoms of posttraumatic stress disorder (PTSD) relate to one another may identify new interventional targets to treat comorbidity and its underlying pathological processes. This study aimed to use network analysis to examine the associations among psychotic experiences; negative symptoms of psychosis; and symptoms of PTSD, anxiety, and depression. In this population-based cohort study, 4,472 participants (36.7% male) were assessed for psychotic experiences, negative symptoms of psychosis, PTSD, anxiety, and depression at age 23 (M = 23.86 years, SD = 0.520) or 24 years (M = 24.03, SD = 0.848). Associations among symptoms were assessed via network analysis. Exploratory graph analysis identified three clusters of densely connected symptoms within the overall network: psychotic experiences; PTSD symptoms; and depressive and anxiety symptoms and negative symptoms of psychosis. Psychotic experiences had the strongest associations with other symptoms in the network, and symptoms of anxiety played a key role in bridging psychotic experiences, symptoms of PTSD, and depressive symptoms. Consistent with the stress reactivity and affective models for psychotic experiences, the results suggest that symptoms of anxiety and emotional distress (e.g., hyperarousal, panic) may have a key role in the development and maintenance of psychotic experiences and symptoms of PTSD. Targeting these symptoms may ameliorate symptom burden transdiagnostically.     

Attenuated Salmonella typhimurium with interleukin 2 gene prevents the establishment of pulmonary metastases in a model of osteosarcoma

Purpose

The current management of osteosarcoma (OS) entails an aggressive preoperative and postoperative chemotherapeutic regimen with limb salvage surgery. Despite these efforts, relapse-free survival is less than 60% in patients with classic OS, whereas most patients relapse with pulmonary metastases. In these studies, we sought to prevent the establishment of pulmonary metastases from OS with a single oral dose of SalpIL2.

Methods

Mice were administered attenuated Salmonella typhimurium with (SalpIL2) and without a gene for human interleukin 2 (Sal-NG) 7 days before challenge with 2 × 10⁵ OS cells via tail vein. Three weeks after injection, mice were harvested for splenic lymphocytes and tumor enumeration.

Results

Prophylaxis with attenuated SalpIL2 significantly reduces pulmonary metastases in number and volume (P < .0001 and P < .0001) with respect to saline controls. Furthermore, splenic natural killer cell populations were increased 396% with SalpIL2 (P < .0007) and 426% with Sal-NG (P < .0003) compared to nontreated groups.

Conclusions

Host natural killer response is greatly amplified and maybe partially responsible for the effective immune response against the formation of pulmonary metastases. A single oral dose of SalpIL2 may be a novel form of adjuvant therapy for patients after early detection of primary OS.     

Long-term follow-up for superior vena cava filter placement

The short-term effectiveness and safety placement of superior vena cava (SVC) filter in the treatment of upper extremity deep venous thrombosis in patients with contraindication to anticoagulation have been well documented. However, as opposed to the numerous reported experiences with inferior vena cava filter placement and its complications, there has been no documented long-term follow-up on SVC filter placement. We, therefore, reviewed our experience with SVC filter placement. A retrospective review was performed of the 154 cases of patients who underwent SVC filter placement between January 1994 and August 2005 at our institution. Seven additional patients had unsuccessful SVC filter placement due to widespread deep venous thrombosis. The data were evaluated for both insertion complications (pneumothorax, hemorrhage, filter misplacement) and long-term complications (pulmonary embolism, migration, caval occlusion). The follow-up included review of serial chest radiographs to evaluate for filter migration in patients who lived at least 60 days after filter insertion and had chest radiography performed (n = 40), patients' charts, clinic visits, and telephone contacts, hospital databases, city death records, and national databases. There were 69 males and 85 females with a mean age of 73.6 years (range, 16-96 years; +/-15.3 [SD] years). Follow-up ranged from 1 day to 3750 days (256.3 +/- 576 days [mean +/- SD]) and 5 patients were lost to follow-up. Of the 154 patients, 58 survived longer than 60 days with mean follow-up of 628.4 days. All SVC filters (TrapEase, n = 38; Greenfield, n = 116) were successfully deployed in the 154 patients. During the follow-up, 114 (74.0% mortality) of the patients died of chronic illness or from cancer complications. There were three cases of pericardial tamponade (1.9%), and one case of misplaced filter in innominate vein. There were no known cases of symptomatic pulmonary embolism, caval occlusion, pneumothorax, or filter migration. SVC filter placement is associated with a low incidence of complications with long-term follow-up. These data help to reaffirm the safety and effectiveness of SVC filter placement. However, SVC perforation in young males remains a significant issue.     

Carotid endarterectomy in patients with chronic renal insufficiency: a recent series of 184 cases

BACKGROUND: The published results of carotid endarterectomy (CEA) in chronic renal insufficiency (CRI) patients are contradictory, mostly because of the relatively small number of patients in these studies. To better assess the neurologic complications and mortality, we reviewed a recent and substantially larger series of CRI patients who underwent CEAs. METHODS: From March 2000 to March 2003, 675 consecutive primary CEAs were performed in 609 patients (346 men, 57%) under general anesthesia. Asymptomatic carotid artery stenosis accounted for 71% of cases. CRI (serum creatinine level > or = 1.5 mg/dL) was detected in 166 patients (27%) who underwent 184 CEAs. The remaining 443 patients (73%) had 491 CEAs. RESULTS: Patients with CRI were different in age (76 +/- 8 years vs 72 +/- 9 years, P < .001), male gender (73% vs 51%, P < .001), coronary artery disease (50% vs 28%, P < .001), and diabetes mellitus incidence (38% vs 27%, P < .02). No significant difference in stroke rates was observed between the CRI patients and the control group (1.2% vs 0.5%). The mortality rate for CRI patients was 3%, whereas it was 0% for the control group ( P < .002). The 143 CRI patients with serum creatinine levels from 1.5 to 2.9 mg/dL had a 0.7% mortality rate, whereas it was 17% for 23 patients with serum creatinine levels of 3 mg/dL or more ( P < .001). The stroke rate for the former group was 0.7% and 4.3% for the latter group (NS). Asymptomatic (16) and symptomatic (7) patients with serum creatinine levels of 3 mg/dL or more had mortality rates of 13% and 28%, respectively, with P = .6. CONCLUSION: The high mortality rate observed in patients with serum creatinine levels of 3 mg/dL or more after CEA calls for a nonoperative approach in the management of asymptomatic patients.     

The efficacy of dietary intervention on urinary risk factors for stone formation in recurrent calcium oxalate stone patients

PURPOSE: Nutrition is suggested to be the major environmental risk factor in idiopathic calcium oxalate stone disease. The study was designed to evaluate the effect of dietary intervention on urinary risk factors for recurrence in calcium oxalate stone formers. MATERIALS AND METHODS: A total of 76 men and 31 women with idiopathic calcium oxalate stone disease collected 24-hour urine on their habitual, self-selected diets and after 7 days on a balanced standardized diet according to the recommendations for calcium oxalate stone formers. RESULTS: On the usual diet, a urine volume of less than 2.0 l per 24 hours was present in 57.9%, hypercalciuria in 25.2%, hypomagnesuria in 18.7%, hyperoxaluria in 14.0%, hyperuricosuria in 41.3% and hypocitraturia in 57.0% of patients. The frequency of metabolic abnormalities and the risk of calcium oxalate stone formation decreased significantly on the ingestion of the balanced diet, due to the significant increase in urinary volume, pH and citrate excretion and the significant decrease in urinary calcium and uric acid excretion. No change occurred in urinary oxalate and magnesium excretion. CONCLUSIONS: The evaluation of urinary risk profiles of the patients on their usual dietary habits revealed a high risk for calcium oxalate stone formation. A low fluid intake and an increased intake of protein and alcohol were identified as the most important dietary risk factors. The shift to a nutritionally balanced diet according to the recommendations for calcium oxalate stone formers significantly reduced the stone forming potential.