Hypothermia does not influence liver damage and function in a porcine polytrauma model

BACKGROUND

Previous studies revealed evidence that induced hypothermia attenuates ischemic organ injuries after severe trauma. In the present study, the effect of hypothermia on liver damage was investigated in a porcine long term model of multi-system injury, consisting of blunt chest trauma, penetrating abdominal trauma, musculoskeletal injury, and hemorrhagic shockMETHODS: In 30 pigs, a standardized polytrauma including blunt chest trauma, penetrating abdominal trauma, musculoskeletal injury, and hemorrhagic shock of 45% of total blood volume was induced. Following trauma, hypothermia of 33∘C was induced for 12 h and intensive care treatment was evaluated for 48 h. As outcome parameters, we assessed liver function and serum transaminase levels as well as a histopathological analysis of tissue samples. A further 10 animals served as controls.

RESULTS

Serum transaminase levels were increased at the end of the observation period following hypothermia without reaching statistical significance compared to normothermic groups. Liver function was preserved (p⩽ 0.05) after the rewarming period in hypothermic animals but showed no difference at the end of the observation period. In H&E staining, cell death was slightly increased hypothermic animals and caspase-3 staining displayed tendency towards more apoptosis in hypothermic group as well.

CONCLUSIONS

Induction of hypothermia could not significantly improve hepatic damage during the first 48 h following major trauma. Further studies focusing on multi-organ failure including a longer observation period are required to illuminate the impact of hypothermia on hepatic function in multiple trauma patients.

Abstract P4-13-05: Detection of local recurrence in premenopausal patients treated with neoadjuvant chemotherapy and mastectomy with or without breast reconstruction

Background: Women who undergo mastectomy for breast cancer treatment often undergo implant based or autologous reconstruction. There are limited data, however, as to whether reconstruction may interfere with detection of a locoregional recurrence. The goal of this study was to assess whether women who undergo reconstruction after mastectomy have an increased risk of local recurrence and/or longer time to local recurrence detection.

Methods: One hundred and fifty-four premenopausal patients who underwent neoadjuvant chemotherapy followed by mastectomy were identified between 2005 and 2015. Patients with de novo Stage IV disease or insufficient medical records were excluded from analysis. Patient and treatment variables were collected, including clinical stage, type of chemotherapy, type of surgery and reconstruction, use of postmastectomy radiotherapy, and use of endocrine therapy. Local recurrence (LR) was defined as a chest wall or skin recurrence. Regional failure (RF) was defined as recurrence in the axilla, supraclavicular fossa, or internal mammary nodes.

Results:

The median follow up for this cohort was 49.9 months. Of the 154 patients, 71 (46%) underwent unilateral mastectomy and 83 (54%) underwent bilateral mastectomies. Thirty patients (19%) elected to forgo reconstruction while 78 (51%) received tissue expander/implant based reconstruction, 29 (19%) received autologous reconstruction, and 17 (11%) had unknown reconstruction histories. Patients who had reconstruction had an increased time to detection of a LR compared to those without reconstruction (p=0.048). However, controlling for the T and N stage of disease, Cox regression demonstrated no observable difference in risk for LR between patients who underwent reconstruction compared to those who didn't. There was no difference in detection of RF between those with and without reconstruction (p=0.092).

Conclusions: Premenopausal patients treated with neoadjuvant chemotherapy followed by mastectomy with any type of reconstructive surgery had an increased time to local recurrence detection compared to those without reconstruction. There was no difference in the risk for local recurrence between those who underwent reconstruction compared to those who didn't.

Citation Format: Jacobson CE, Kozak M, Walck E, Hawley E, Horst K. Detection of local recurrence in premenopausal patients treated with neoadjuvant chemotherapy and mastectomy with or without breast reconstruction [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-13-05.

Abstract P6-08-04: National trends in mastectomy for operable breast cancers treated with neoadjuvant chemotherapy

Objective: Although neoadjuvant chemotherapy (NAC) has not been shown to improve survival compared with adjuvant therapy for patients with operable invasive breast cancer (IBC), it is often used to allow more limited surgery in the breast and axilla without compromising local control. We sought to evaluate national trends in mastectomy among patients with operable breast cancer treated with NAC and to characterize the contribution of demographic and tumor characteristics to changing trends.

Methods: We queried the National Cancer Database (NCDB) 2014 Participant User File for adult women who underwent surgery and received chemotherapy for unilateral T1-3N0-3M0 IBC diagnosed between 2010 and 2014. Surgery was classified as lumpectomy (BCS), unilateral mastectomy (UM) or bilateral mastectomy (BM). Molecular subtype was categorized according to ER, PR, and HER2 status. We used logistic regression to model surgery use (BM or UM vs BCS), adjusting for the following clinical covariates that were selected a priori: age, race/ethnicity, year of diagnosis, comorbidity score, metropolitan vs urban/rural residence, patient distance from treating facility, % with less than high school education (zip code based), insurance type, clinical stage, histology, and molecular subtype. As those who achieved pathologic complete response (pCR) after NAC should be ideal candidates for BCS, we also looked at this group separately. We then performed sensitivity analyses further controlling for region of the country and facility type, and for facility.

Results: We identified 235,339 patients who fulfilled our inclusion criteria. Of these patients, 25.3% were treated with NAC. Rates of pCR increased from 33.3% in 2010 to 46.3% in 2014 (p<0.001). Rates of BCS increased from 37.0% in 2010 to 40.8% in 2014 (p<0.001). While rates of UM decreased from 43.3% in 2010 to 34.7% in 2014 (p<0.001), rates of BM with or without reconstruction increased from 19.7% in 2010 to 24.6% in 2014 (p<0.001). Rates of BM without immediate reconstruction remained stable over time, from 11.8% in 2010 to 11.5% in 2014.

Among patients who received NAC, factors that were independently associated with both UM and BM (versus BCS) for both the entire cohort and those who achieved pCR included younger age, greater patient distance from facility, and higher clinical stage. Factors that were inversely associated with both UM and BM included black race and ductal histology. More recent year of diagnosis was inversely associated with UM and directly associated with BM. Asian race was associated with UM while non-Hispanic white race was associated with BM. Private or managed care insurance and higher area education were also associated with BM. These results were materially unchanged in sensitivity analyses.

Conclusion: Rates of pCR have increased over time among patients with operable IBC treated with NAC. While the rate of UM has declined over time, the rate of BM has increased. Significant sociodemographic differences exist between women who undergo BCS, and women who undergo UM and BM. Further study of factors that influence surgical decision-making in the NAC setting is warranted.

Citation Format: Pollom E, Qian Y, Dirbas F, Horst K, Tsai CJ. National trends in mastectomy for operable breast cancers treated with neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-08-04.

Cardiac Depression in Pigs after Multiple Trauma - Characterization of Posttraumatic Structural and Functional Alterations

The purpose of this study was to define the relationship between cardiac depression and morphological and immunological alterations in cardiac tissue after multiple trauma. However, the mechanistic basis of depressed cardiac function after trauma is still elusive. In a porcine polytrauma model including blunt chest trauma, liver laceration, femur fracture and haemorrhage serial trans-thoracic echocardiography was performed and correlated with cellular cardiac injury as well as with the occurrence of extracellular histones in serum. Postmortem analysis of heart tissue was performed 72 h after trauma. Ejection fraction and shortening fraction of the left ventricle were significantly impaired between 4 and 27 h after trauma. H-FABP, troponin I and extracellular histones were elevated early after trauma and returned to baseline after 24 and 48 h, respectively. Furthermore, increased nitrotyrosine and Il-1β generation and apoptosis were identified in cardiac tissue after trauma. Main structural findings revealed alteration of connexin 43 (Cx43) and co-translocation of Cx43 and zonula occludens 1 to the cytosol, reduction of α-actinin and increase of desmin in cardiomyocytes after trauma. The cellular and subcellular events demonstrated in this report may for the first time explain molecular mechanisms associated with cardiac dysfunction after multiple trauma.

Comparative study on the treatment of Rockwood type III acute acromioclavicular dislocation: Clinical results from the TightRope® technique vs. K-wire fixation

BACKGROUND AND HYPOTHESIS

The aim of this study was to address the inconsistency regarding the operative treatment of Rockwood type III acromioclavicular joint separation. We compared results after single- and double TightRope^® reduction with results after acromioclavicular transfixation via K-wires only and additional ligament augmentation in acute acromioclavicular (AC) joint separations graded Rockwood type III, and hypothesized that the TightRope^® technique leads to better clinical and radiological results.

MATERIALS AND METHODS

We conducted a retrospective clinical cohort study and included 42 consecutive patients (mean age 43 years [24-66]) diagnosed and operatively treated between 2004 and 2012 (mean follow-up was 54.6 months [15-118]). Specific shoulder scores as well as scores reflecting the patients' overall mental and physical health status were used. Radiological evaluation was also performed.

RESULTS

The SF12 test revealed comparability between all subgroups. Specific shoulder tests and a visual analogue scale demonstrated comparable results. Radiographic measurements showed a significant reduction in the AC distance and CC distance after surgery in all subgroups. The early complication rate was 9.5% for all patients, while late complications occurred in 14.3% of all cases.

CONCLUSIONS

Compared to the established methods, the operative TightRope^® procedures represent a safe alternative in Rockwood III injuries. All investigated techniques predominantly led to good and excellent clinical results in acute Rockwood type III AC joint instabilities. Avoidance of material removal and shorter hospital stays appear to speak in favour for the TightRope^® technique.

LEVEL OF EVIDENCE

IV.

Characterization of blunt chest trauma in a long-term porcine model of severe multiple trauma

Chest trauma has a significant relevance on outcome after severe trauma. Clinically, impaired lung function typically occurs within 72 hours after trauma. However, the underlying pathophysiological mechanisms are still not fully elucidated. Therefore, we aimed to establish an experimental long-term model to investigate physiological, morphologic and inflammatory changes, after severe trauma. Male pigs (sus scrofa) sustained severe trauma (including unilateral chest trauma, femur fracture, liver laceration and hemorrhagic shock). Additionally, non-injured animals served as sham controls. Chest trauma resulted in severe lung damage on both CT and histological analyses. Furthermore, severe inflammation with a systemic increase of IL-6 (p = 0.0305) and a local increase of IL-8 in BAL (p = 0.0009) was observed. The pO₂/FiO₂ ratio in trauma animals decreased over the observation period (p < 0.0001) but not in the sham group (p = 0.2967). Electrical Impedance Tomography (EIT) revealed differences between the traumatized and healthy lung (p < 0.0001). In conclusion, a clinically relevant, long-term model of blunt chest trauma with concomitant injuries has been developed. This reproducible model allows to examine local and systemic consequences of trauma and is valid for investigation of potential diagnostic or therapeutic options. In this context, EIT might represent a radiation-free method for bedside diagnostics.

[The rotationally stable screw-anchor with trochanteric stabilizing plate (RoSA/TSP) : First results in unstable trochanteric femur fractures]

BACKGROUND

In unstable trochanteric fractures, the extramedullary rotationally stable screw-anchor (RoSA) combines the benefits of the load and rotational stability of the blade with the advantages of the screw (pull-out resistance, compression capability) in a single load carrier, and was designed to prevent femoral neck shortening by using an additional locked trochanteric stabilizing plate (TSP).

OBJECTIVES

The aim of the current prospective cohort study was the clinical evaluation of the RoSA/TSP system regarding the mechanical re-operation rate and the amount of postoperative femoral neck shortening.

METHODS

From September 2011 to January 2014 80 patients with unstable trochanteric fractures underwent internal extramedullary fixation with the RoSA/TSP (Königsee Implantate GmbH, Allendorf, Germany). Due to fracture stability and after induction of compression, additional long locked antitelescoping screws (AT, n = 1-4) were placed reaching the femoral head. Radiological (femoral neck shortening) and clinical re-examination of patients (n = 61) was performed 6-10 weeks and 6-10 months later.

RESULTS

In the 61 re-examined patients (76 %) femoral neck shortening was very low with 2 mm 6-10 months after operation. Re-operations occurred in 8 % (n = 6) and in 4 % (n = 3) as prophylactic surgical intervention. Whereas one-third (4 %) of re-operations occurred due to iatrogenic surgical problems from the first operation two-thirds of patients (8 %) had a re-operation due to delay of bone union (3× nonunion, 3 planned removals of AT-screws to improve healing). The in-hospital mortality was 3 % (n = 2).

CONCLUSIONS

The fixation of unstable trochanteric femur fractures using the RoSA/TSP in a first clinical setting led to a great primary stability, with significant advantages with regard to limited femoral neck shortening. However, the rigidity of the construct with its consequences regarding bone healing can be challenging for the surgeon. Nevertheless, in some cases of revision it could be beneficial for stability.

Reconstruction of a quadriceps tendon tear using Polyvinylidene fluoride sutures and patellar screw fixation: A biomechanical study

BACKGROUND

Acute quadriceps tendon tears are infrequent injuries requiring surgical treatment. Improved stability after surgical repair may allow for earlier weight-bearing and range of motion. Therefore, a new implant was tested and compared with the "gold standard", using transosseous sutures.

METHODS

Quadriceps tendon tears were constructed using a cadaveric model of 12 fresh matched-pair specimens (aged 61-97; mean age: 82 years). The biomechanical testing compared non-absorbable suture anchors (Polyvinylidene fluoride) versus transosseous absorbable sutures (Polydioxanon). Following anatomic reconstruction, the repaired specimens were loaded until they failed (testing machine: Hounsfield H10KM, Redhill, United Kingdom; maximum force: 1000 N; load speed: 25 mm/min; maximum test length: 150 mm; pre-load: 5 N). Values for load until tear displacement, maximum load until complete failure of the construct (pullout or breakage of the sutures or anchors) and stiffness of the reconstruction were recorded.

RESULTS

The stiffness found in the Polyvinylidene fluoride reconstruction (mean 9.83 N/mm) (standard deviation (SD) 7.75) showed a significant increase compared to the Polydioxanon reconstruction (mean 6.66 N/mm (SD 3.32); P=0.045). Transosseous fixation showed comparable results to the suture anchor system. There was no significant difference found in the maximum load to tear displacement (PVDF: 290.88 N (SD 106.01) vs. PDS: 266.75 N (SD 82.61); P=0.358).

CONCLUSIONS

Using the Polyvinylidene fluoride thread showed comparable results to the established method in reconstruction of ruptured quadriceps tendon. Stiffness of the Polyvinylidene fluoride thread reconstruction was even greater than Polydioxanon thread.

CLINICAL RELEVANCE

Improved stiffness may facilitate healing and is suggested as clinical relevance in reconstruction.

A porcine polytrauma model with two different degrees of hemorrhagic shock: outcome related to trauma within the first 48 h

BACKGROUND

An animal polytrauma model was developed, including trunk and extremity injuries combined with hemorrhagic shock and a prolonged post-traumatic phase. This could be useful for the assessment of different therapeutic approaches during intensive care therapy.

METHODS

A standardized polytrauma including lung contusion, liver laceration and lower leg fracture was applied in 25 pigs. They underwent controlled haemorrhage either with a blood volume loss of 45 % and a median arterial pressure (MAP) <30 mmHg/90 min (group L, n = 15) or a 50 % blood loss of and an MAP <25 mmHg/120 min (group H, n = 10). Five non-traumatized pigs served as a control (group C). Subsequently, intensive care treatment was given for an observational period of 48 h.

RESULTS

Both trauma groups showed signs of shock and organ injury (heart rate, MAP and lactate). The frequency of cardiopulmonary resuscitation (CPR) and lung injury was directly related to the severity of the haemorrhagic shock (CPR-group L: 4 of 15 pigs, group H: 4 of 10 pigs; Respiratory failure-group L: 3 of 13, group H: 3 of 9. There was no difference in mortality between trauma groups.

CONCLUSION

The present data suggest that our model reflects the mortality and organ failure of polytrauma in humans during shock and the intensive care period. This suggests that the experimental protocol could be useful for the assessment of therapeutic approaches during the post-traumatic period.

Impact of age on the clinical outcomes of major trauma

PURPOSE

In view of demographic changes over the past few decades, the average age of trauma patients is progressively increasing. We therefore aimed to summarize the specific characteristics of geriatric trauma and to identify potential fields for further research to improve the care of elderly trauma patients.

METHODS

Review of the literature.

RESULTS

Due to the diverse risk factors (e.g., pre-existing conditions, limited physiological reserve), geriatric patients are prone to developing severe complications, even after less severe trauma. Yet, age is not considered as the only predictor of worse outcomes, and it should not be considered the only criterion for limiting care in those patients. It is crucial that age-specific treatment guidelines are developed to optimize the outcomes for senior trauma patients. Based on the current literature, these guidelines should emphasize the importance of field triage directly to a trauma center, along with the activation of the trauma team. Furthermore, early intensive monitoring, aggressive resuscitation, and time of surgical intervention are of upmost importance to reduce mortality.

CONCLUSION

The impact of several factors [age, premedical conditions (PMC), decreased physiological reserves, and impaired immune function] on the post-traumatic course of elderly trauma patients needs to be clarified in future experimental and clinical studies for the early identification of geriatric high-risk patients and for the development of age-adapted therapeutic strategies.

Impact of haemorrhagic shock intensity on the dynamic of alarmins release in porcine poly-trauma animal model

PURPOSE

Traumatic insults result in an altered inflammatory response, in which alarmins release has a central role. The impact of haemorrhagic shock intensity on the long-term kinetics of alarmins is not yet fully elucidated. We investigated these aspects in a combined trauma (chest, abdominal, and extremities injury) porcine model with different severities and durations of haemorrhagic shock.

METHODS

After induction of combined trauma (tibia fracture, lung contusion, and liver laceration), haemorrhagic shock was induced at different intensities: moderate haemorrhage (MH; n = 15): mean arterial pressure (MAP) <30 ± 5 mmHg [maximum loss of total blood volume (TBVmax): 45 %] for 90 min, and severe haemorrhage (SH; n = 10): MAP <25 ± 5 mmHg (TBVmax 50 %) for 120 min. Resuscitation was performed using a standardized crystalloid infusion protocol. Animals were mechanically ventilated and underwent ICU-monitoring for 48 h (MH) and 48.5 h (SH). Blood samples were collected over the clinical time course, and systemic levels of serum alarmins [High-Mobility Group Protein B-1 (HMGB-1) and Heat Shock Protein 70 (HSP70)] were measured using an ELISA kit.

RESULTS

Heart rate, systemic blood pressure, lactate, and base excess were significantly altered as a function of haemorrhagic shock in both trauma groups (MH and SH). Systemic HMGB-1 levels were significantly elevated in both trauma groups when compared to the sham group. Haemorrhagic shock severity and duration were positively correlated with HMGB-1 levels and compared to baseline values, concentrations remained significantly increased in SH when compared to MH. On the other hand, we observed a significant decrease in the systemic HSP70 levels of trauma groups (MH, and SH) when compared to the sham group, which was significantly decreased compared to baseline values in SH over the entire time course.

CONCLUSION

Our data show that haemorrhagic shock duration and severity affect the systemic levels of HMGB-1 and HSP70. This early alarmins release after trauma can be used to guide the treatment strategies (e.g. surgical procedures) of polytrauma patients.

Open versus Percutaneous Stabilization of Thoracolumbar Spine Fractures: A Short-Term Functional and Radiological Follow-up

PURPOSE OF THE STUDY

A prospective cohort study evaluates the functional and radiological outcome of thoracolumbar spine fractures treated either with open or percutaneous dorsal instrumentation. In recent years, several studies advocate percutaneous stabilization of spinal fractures in patients without neurological deficits. However, it is still debated whether percutaneous stabilization is superior to open dorsal instrumentation in spinal trauma.

MATERIAL AND METHODS

This study was performed between 2010 and 2012 at a Level 1 trauma center. Patients treated either with an open or a percutaneous dorsal instrumentation for traumatic fractures of the thoracolumbar spine (T11 to L2) were included. Fracture morphology, screw positioning and clinical parameters were analyzed. Standardized questionnaires (VAS-spine-score; Oswestry-disability-score; SF-36) and follow up radiographs were performed.

RESULTS

Overall 72 patients (29 percutaneous; 43 open) could be included. The surgical and the early postsurgical course were similar between both groups. Furthermore the operative approach had no influence on the functional and radiological outcome one year after surgery, but the questionnaires showed moderate impairments within both groups. Also both groups showed a significant loss of reduction after the first postoperative month (p < 0.01). Within the open group a significantly higher amount of fracture reduction (p < 0.01) and a significantly reduced intraoperative radiation exposure was seen (open 105.9 sec.; percutaneous 143.1 sec; p < 0.05); whereas the percutaneous approach was associated with significantly reduced intraoperative blood loss (open 2.2 g/dl; percutaneous 1.2 g/dl; p < 0.001).

CONCLUSION

The functional and the radiological outcome of both groups was comparable one year after trauma. Minor advantages of the percutaneous system was less blood loss, whereas the open approach was associated with a significantly higher amount of initial reduction and significantly less intraoperative radiation exposure. Independent from the type of posterior fixation loss of reduction was already significant in the early postoperative course.

A meta-analysis of operative versus nonoperative treatment in 463 scapular neck fractures

BACKGROUND AND AIMS

Treatment of scapular neck fractures remains controversial. Advantages of surgical treatments, such as anatomical restoration of fracture displacement, are counterbalanced by approach morbidity. We conducted a meta-analysis of 463 scapular neck fractures and compared clinical, functional, and radiographical outcomes in operatively and nonoperatively treated scapular neck fractures.

MATERIAL AND METHODS

A literature search was conducted, including the databases PubMed/MEDLINE, Embase, and the Cochrane Database of Systematic Reviews. Manuscripts were included if they reported a precise description of treatment, complications, functional outcomes, and/or radiographic evaluation. Data about day-to-day activities, level of pain-freeness, range of motion, functional grading, and radiographical assessment were pooled and compared using fixed effects models.

RESULTS AND CONCLUSIONS

A total of 22 manuscripts were relevant, including 1 prospective cohort study and 21 retrospective studies. The studies showed a high heterogeneity in the result assessment. Most patients had concomitant injuries. In total, 234 out of the 463 fractures were treated operatively. Pain-freeness and radiographic outcome measurements were significantly better in the operatively treated group, whereas range of motion was significantly improved in the nonoperative treated patients. Complication rate for surgical treatment was about 10%. From the achievable data, there was no bias detected when comparing the two treatment groups. However, those data could not be analyzed for all included studies. For the same reason, the role of additional surgical treatment for concomitant injuries to the shoulder girdle could not be cleared completely. Caution should be exercised, and individual injury patterns have to be taken into consideration when considering the best treatment options.

Assessment of coincidence and defect sizes in Bankart and Hill-Sachs lesions after anterior shoulder dislocation: a radiological study

OBJECTIVE

Bankart and Hill-Sachs lesions are often associated with anterior shoulder dislocation. The MRI technique is sensitive in diagnosing both injuries. The aim of this study was to investigate Bankart and Hill-Sachs lesions with MRI to determine the correlation in occurrence and defect sizes of these lesions.

METHODS

Between 2006 and 2013, 446 patients were diagnosed with an anterior shoulder dislocation and 105 of these patients were eligible for inclusion in the study. All patients were examined using MRI. Bankart lesions were classified as cartilaginous or bony lesions. Hill-Sachs lesions were graded I-III using a modified Calandra classification.

RESULTS

The co-occurrence of injuries was high [odds ratio (OR) = 11.47; 95% confidence interval (CI) = 3.60-36.52; p < 0.001]. Patients older than 29 years more often presented with a bilateral injury (OR = 16.29; 95% CI = 2.71-97.73; p = 0.002). A correlation between a Bankart lesion and the grade of a Hill-Sachs lesion was found (ρ = 0.34; 95% CI = 0.16-0.49; p < 0.001). Bankart lesions co-occurred more often with large Hill-Sachs lesions (O  = 1.24; 95% CI = 1.02-1.52; p = 0.033).

CONCLUSION

If either lesion is diagnosed, the patient is 11 times more likely to have suffered the associated injury. The size of a Hill-Sachs lesion determines the co-occurrence of cartilaginous or bony Bankart lesions. Age plays a role in determining the type of Bankart lesion as well as the co-occurrence of Bankart and Hill-Sachs lesions.

ADVANCES IN KNOWLEDGE

This study is the first to demonstrate the use of high-quality MRI in a reasonably large sample of patients, a positive correlation of Bankart and Hill-Sachs lesions in anterior shoulder dislocations and an association between the defect sizes.

The long-term clinical outcome after pelvic ring injuries

We report the functional and socioeconomic long-term outcome of patients with pelvic ring injuries.

We identified 109 patients treated at a Level I trauma centre between 1973 and 1990 with multiple blunt orthopaedic injuries including an injury to the pelvic ring, with an Injury Severity Score (ISS) of ≥ 16. These patients were invited for clinical review at a minimum of ten years after the initial injury, at which point functional results, general health scores and socioeconomic factors were assessed.

In all 33 isolated anterior (group A), 33 isolated posterior (group P) and 43 combined anterior/posterior pelvic ring injuries (group A/P) were included. The mean age of the patients at injury was 28.8 years (5 to 55) and the mean ISS was 22.7 (16 to 44).

At review the mean Short-Form 12 physical component score for the A/P group was 38.71 (22.12 to 56.56) and the mean Hannover Score for Polytrauma Outcome subjective score was 67.27 (12.48 to 147.42), being significantly worse compared with the other two groups (p = 0.004 and p = 0.024, respectively). A total of 42 patients (39%) had a limp and 12 (11%) required crutches. Car or public transport usage was restricted in 16 patients (15%). Overall patients in groups P and A/P had a worse outcome. The long-term outcome of patients with posterior or combined anterior/posterior pelvic ring injuries is poorer than of those with an isolated anterior injury.

Cite this article: Bone Joint J 2013;95-B:548–53.

Indications for bullet removal: overview of the literature, and clinical practice guidelines for European trauma surgeons

PURPOSE

The incidence of gunshot wounds from civilian firearms is increasing. Despite this fact, guidelines on indications for bullet removal are scarce. In this analysis, we combine an overview of the available literature in these rare entities with our experiences in our own clinical practices.

METHODS

We conducted a systematic literature search of computerized bibliographic databases (Medline, EMBASE, and the Cochrane Central Register). The local experience of the authors was reviewed in light of the available literature.

RESULTS

145 full-text articles were suitable for further evaluation. Only six retrospective studies were available, and no prospective study could be retrieved. Most of the articles were case reports. In the South African co-author's own clinical practice, approximately 800 patients are treated per year with gunshot wounds.

CONCLUSIONS

In summary, there are only a few clear indications for bullet removal. These include bullets found in joints, CSF, or the globe of the eye. Fragments leading to impingement on a nerve or a nerve root, and bullets lying within the lumen of a vessel, resulting in a risk of ischemia or embolization, should be removed. Rare indications are lead poisoning caused by a fragment, and removal that is required for a medico-legal examination. In all other cases the indication should be critically reviewed.

Complete genome sequence of Treponema pallidum, the syphilis spirochete

The complete genome sequence of Treponema pallidum was determined and shown to be 1,138,006 base pairs containing 1041 predicted coding sequences (open reading frames). Systems for DNA replication, transcription, translation, and repair are intact, but catabolic and biosynthetic activities are minimized. The number of identifiable transporters is small, and no phosphoenolpyruvate:phosphotransferase carbohydrate transporters were found. Potential virulence factors include a family of 12 potential membrane proteins and several putative hemolysins. Comparison of the T. pallidum genome sequence with that of another pathogenic spirochete, Borrelia burgdorferi, the agent of Lyme disease, identified unique and common genes and substantiates the considerable diversity observed among pathogenic spirochetes.

Genomic sequence of a Lyme disease spirochaete, Borrelia burgdorferi

The genome of the bacterium Borrelia burgdorferi B31, the aetiologic agent of Lyme disease, contains a linear chromosome of 910,725 base pairs and at least 17 linear and circular plasmids with a combined size of more than 533,000 base pairs. The chromosome contains 853 genes encoding a basic set of proteins for DNA replication, transcription, translation, solute transport and energy metabolism, but, like Mycoplasma genitalium, it contains no genes for cellular biosynthetic reactions. Because B. burgdorferi and M. genitalium are distantly related eubacteria, we suggest that their limited metabolic capacities reflect convergent evolution by gene loss from more metabolically competent progenitors. Of 430 genes on 11 plasmids, most have no known biological function; 39% of plasmid genes are paralogues that form 47 gene families. The biological significance of the multiple plasmid-encoded genes is not clear, although they may be involved in antigenic variation or immune evasion.