Surgical management and outcomes following atypical subtrochanteric femoral fractures - results from a matched-pair analysis of the registry for geriatric trauma of the German Trauma Society

BACKGROUND AND OBJECTIVES

The outcomes of patients with atypical subtrochanteric fractures (ASFs) remain unclear. Data from a large international geriatric trauma registry were analysed to examine the outcome of patients with ASFs compared to patients with typical osteoporotic subtrochanteric fractures (TSFs).

MATERIALS AND METHODS

Data from the Registry for Geriatric Trauma of the German Trauma Society (Deutsche Gesellschaft für Unfallchirurgie [DGU]) (ATR-DGU) were analysed. All patients treated surgically for ASFs or TSFs were included in this analysis. Across both fracture types, a paired matching approach was conducted, where statistical twins were formed based on background characteristics sex, age, American Society of Anesthesiologists (ASA) score and walking ability. In-house mortality and mortality rates at the 120-day follow-up, as well as mobility at 7 and 120 days, the reoperation rate, hospital discharge management, the hospital readmission rate at the 120-day follow-up, health-related quality of life, type of surgical treatment and anti-osteoporotic therapy at 7 and 120 days, were assessed as outcome measures using a multivariate logistic regression analysis.

RESULTS

Amongst the 1,800 included patients, 1,781 had TSFs and 19 had ASFs. Logistic regression analysis revealed that patients with ASFs were more often treated with closed intramedullary nailing (RR = 3.59, p < 0.001) and had a higher probability of vitamin D supplementation as osteoporosis therapy at 120 days (RR = 0.88, p < 0.002). Patients with ASFs were also more likely to live at home after surgery (RR = 1.43, p < 0.001), and they also tended to continue living at home more often than patients with TSFs (RR = 1.33, p < 0.001). Accordingly, patients with TSFs had a higher relative risk of losing their self-sufficient living status, as indicated by increased rates of patients living at home preoperatively and being discharged to nursing homes (RR = 0.19, p < 0.001) or other hospitals (RR = 0.00, p < 0.001) postoperatively.

CONCLUSIONS

Surgical treatment of ASFs was marked by more frequent use of closed intramedullary fracture reduction. Furthermore, patients with ASFs were more likely to be discharged home and died significantly less often in the given timeframe. The rate of perioperative complications, as indicated by nonsignificant reoperation rates, as well as patient walking abilities during the follow-up period, remained unaffected.

Reality of treatment for severely injured patients: are there age-specific differences?

BACKGROUND

Major trauma and its consequences are one of the leading causes of death worldwide across all age groups. Few studies have conducted comparative age-specific investigations. It is well known that children respond differently to major trauma than elderly patients due to physiological differences. The aim of this study was to analyze the actual reality of treatment and outcomes by using a matched triplet analysis of severely injured patients of different age groups.

METHODS

Data from the TraumaRegister DGU® were analyzed. A total of 56,115 patients met the following inclusion criteria: individuals with Maximum Abbreviated Injury Scale > 2 and < 6, primary admission, from German-speaking countries, and treated from 2011-2020. Furthermore, three age groups were defined (child: 3-15 years; adult: 20-50 years; and elderly: 70-90 years). The matched triplets were defined based on the following criteria: 1. exact injury severity of the body regions according to the Abbreviated Injury Scale (head, thorax, abdomen, extremities [including pelvis], and spine) and 2. level of the receiving hospital.

RESULTS

A total of 2,590 matched triplets could be defined. Traffic accidents were the main cause of severe injury in younger patients (child: 59.2%; adult: 57.9%). In contrast, low falls (from < 3 m) were the most frequent cause of accidents in the elderly group (47.2%). Elderly patients were least likely to be resuscitated at the scene. Both children and elderly patients received fewer therapeutic interventions on average than adults. More elderly patients died during the clinical course, and their outcome was worse overall, whereas the children had the lowest mortality rate.

CONCLUSIONS

For the first time, a large patient population was used to demonstrate that both elderly patients and children may have received less invasive treatment compared with adults who were injured with exactly the same severity (with the outcomes of these two groups being opposite to each other). Future studies and recommendations should urgently consider the different age groups.

Liberal intraoperative fluid management leads to increased complication rates in geriatric patients with hip fracture

PURPOSE

Fractures of the proximal femur in geriatric patients are life-changing and life-threatening events. Previous research has identified fluid volume as an independent factor contributing to trauma patients' complications. Therefore, we aimed to investigate the impact of intraoperative fluid volume on outcomes in geriatric patients undergoing hip fracture surgery.

METHODS

We conducted a retrospective single-center study with data from the hospital information systems. Our study included patients aged 70 years or older who had sustained a proximal femur fracture. We excluded patients with pathologic, periprosthetic, or peri-implant fractures and those with missing data. Based on the fluids given, we divided patients into high-volume and low-volume groups.

RESULTS

Patients with a higher American Society of Anesthesiologists (ASA) grade and more comorbidities were more likely to receive more than 1500 ml of fluids. We observed significant differences in anesthesiologic management between the two groups, with a higher rate of invasive blood pressure management (IBP) and central venous catheter usage in the high-volume group. High-volume therapy was associated with a higher rate of complications (69.7% vs. 43.6%, p < 0.01), a higher transfusion rate (odds ratio 1.91 [1.26-2.91]), and an increased likelihood of patients being transferred to an intensive care unit (17.1% vs. 6.4%, p = 0.009). These findings were confirmed after adjusting for ASA grade, age, sex, type of fracture, Identification-of-Seniors-At-Risk (ISAR) score, and intraoperative blood loss.

CONCLUSIONS

Our study suggests that intraoperative fluid volume is a significant factor that impacts the outcome of hip fracture surgery in geriatric patients. High-volume therapy was associated with increased complications.

Spinal anesthesia with better outcome in geriatric hip fracture surgery - An analysis of the Registry for Geriatric Trauma (ATR-DGU)

BACKGROUND

Literature shows conflicting results regarding spinal (SA) or general anesthesia (GA) and their influence on the outcome of elderly patients with hip fractures. We, therefore, conducted an analysis from the Registry for Geriatric Trauma (ATR-DGU).

METHODS

A retrospective, multicenter registry study including patients aged 70 years or above with hip fractures requiring surgery from 131 Centers for Geriatric Trauma (AltersTraumaZentrum DGU®) from 2016 to 2021. Patients with SA or GA were compared using matched-pair analysis and linear and logistic regression models.

RESULTS

A total of 43,714 patients were included, of whom 3,242 received SA. The median age was 85 (SA) and 84 years (GA). Adjustments for the American Society of Anesthesiologists (ASA) grade, sex, age, additional injuries, and anticoagulation resulted in a higher in-hospital (odds ratio (OR) 1.31; 95% confidence interval [CI], 1.07 - 1.61, p = 0.009) and 120 days mortality (OR 1.47; 95% CI, 1.1 - 1.95, p = 0.009) in the GA group. GA had a significant negative influence on walking ability seven days after surgery and on the quality of life (QoL). The length of hospital stay (LoS) was significantly shorter in the SA group.

CONCLUSIONS

SA is associated with a higher survival rate, a better walking ability seven days after surgery, a higher QoL, and a shorter LoS.

The Geriatrics at Risk Score (GeRi-Score) for mortality prediction in geriatric patients with proximal femur fracture - a development and validation study from the Registry for Geriatric Trauma (ATR-DGU)

This study developed an easy-to-use mortality prediction tool, which showed an acceptable discrimination and no significant lack of fit. The GeRi-Score was able to predict mortality and could distinguish between mild, moderate and high risk groups. Therefore, the GeRi-Score might have the potential to distribute the intensity of medical care.

PURPOSE

Several mortality-predicting tools for hip fracture patients are available, but all consist of a high number of variables, require a time-consuming evaluation and/or are difficult to calculate. The aim of this study was to develop and validate an easy-to-use score, which depends mostly on routine data.

METHODS

Patients from the Registry for Geriatric Trauma were divided into a development and a validation group. Logistic regression models were used to build a model for in-house mortality and to obtain a score. Candidate models were compared using Akaike information criteria (AIC) and likelihood ratio tests. The quality of the model was tested using the area under the curve (AUC) and the Hosmer-Lemeshow test.

RESULTS

38,570 patients were included, almost equal distributed to the development and to the validation dataset. The AUC was 0.727 (95% CI 0.711 - 0.742) for the final model, AIC resulted in a significant reduction in deviance compared to the basic model, and the Hosmer-Lemeshow test showed no significant lack of fit (p = 0.07). The GeRi-Score predicted an in-house mortality of 5.3% vs. 5.3% observed mortality in the development dataset and 5.4% vs. 5.7% in the validation dataset. The GeRi-Score was able to distinguish between mild, moderate and high risk groups.

CONCLUSIONS

The GeRi-Score is an easy-to-use mortality-predicting tool with an acceptable discrimination and no significant lack of fit. The GeRi-Score might have the potential to distribute the intensity of perioperative medical care in hip fracture surgery and can be used in quality management programs as benchmark tool.

Does stem profile have an impact on the failure patterns in revision total knee arthroplasty?

INTRODUCTION

Revision total knee arthroplasty (RTKA) has been increasing continuously. The results of RTKA still remain unsatisfactory. Failure patterns and risk factors in RTKA were thoroughly analyzed, with periprosthetic joint infections (PJI) and aseptic loosening remaining at the forefront of re-revision (ReRTKA) causes. While there is evidence that stem profile impacts the revisability of cemented implants, its association with the modes of RTKA failure is unknown.

METHODS

50 consecutive ReRTKA performed in a single orthopedic center during 2016-2017 were retrospectively analyzed. The cases were stratified according to age, sex, number of preexisting revisions, fixation technique, stem design and causes of re-revision. All explanted implants with conical vs. cylindrical stem profiles were compared.

RESULTS

Mean age was 67 ± 11.5, and 54% were females. 72% of the cases had ≥ 3 previous revisions. 88% were full-cemented, 3% hybrid and 9% press-fit stems. 36% of the RTKA had conical, 58% cylindrical and 6% combined stem profiles. 92% of the RTKA components were removed. Removal causes were: PJI (52.2%), aseptic loosening (34.8%), implant malposition (9.8%), painful knee (1.1%) and instability (2.2%). While the overall RTKA failure patterns were equally distributed between conical and cylindrical stems, subgroup analysis of only cemented ReRTKA revealed a higher incidence of aseptic loosening within cylindrical stem profiles (46.7% vs. 25.7%, P = 0.05).

CONCLUSION

Stem profile may have an impact on the process of aseptic loosening in cemented non-metaphyseal engaging RTKA, with cylindrical designs tending to worse outcomes than conical designs. Large cohort studies could provide more clarity on current observation.

The Influence of Malnutrition Measured by Hypalbuminemia and Body Mass Index on the Outcome of Geriatric Patients with a Fracture of the Proximal Femur

Background and Objectives: Fractures of the proximal femur are a life-changing and life-threatening event for older people. Concomitant malnutrition has been described as an independent risk factor for complications and mortality. Therefore, we examined the influence of albumin and body mass index (BMI) as parameters for the nutritional state on the outcome after geriatric hip fracture surgery. Materials and Methods: Data were retrospectively collected from hospital information systems, and complications and all other parameters were obtained from patient charts. We included patients aged 70 years or above with a fracture of the proximal femur. We excluded periprosthetic and peri-implant fractures and patients with a missing BMI or albumin value. Results: Patients with a BMI below 20 kg/m² were more likely to be female but did not differ from the normal BMI group in terms of baseline parameters. Patients with hypoalbuminemia had a higher ASA grade and Charlson Comorbidity Index, as well as a lower hemoglobin value and prothrombin time compared to those with normal albumin values and low BMI. Hypoalbuminemia was associated with significantly increased rates of complications (57.9% vs. 46.7%, p = 0.04) and mortality (10.3% vs. 4.1%, p = 0.02). Blood loss and transfusion rates were higher in the hypoalbuminemia group. Patients with a BMI below 20 kg/m² had a higher risk of intraoperative cardiac arrest (2.6% vs. 0.4%, p = 0.05) but did not show higher mortality rates than patients with a BMI above 20 kg/m². However, the outcome parameter could not be confirmed in the regression analysis. Conclusions: Hypoalbuminemia might be an indicator for more vulnerable patients with a compromised hemoglobin value, prothrombin time, and ASA grade. Therefore, it is also associated with higher mortality and postoperative complications. However, hypoalbuminemia was not an independent predictor for mortality or postoperative complications, but low albumin values were associated with a higher CCI and ASA grade than in patients with a BMI below 20 kg/m².

Muscle Injury Around the Shoulder

Acute shoulder tendon and intra-articular injuries are common and their imaging well described. However, a subset of patients present with more unusual acute shoulder muscle injury. Of these, pectoralis major muscle injuries are encountered the most often and are increasingly prevalent due to a focus on personal fitness, particularly bench-press exercises. Other muscle injuries around the shoulder are rare. This article reviews the anatomy, mechanism of injury, and the imaging findings in relation to injuries of these muscles around the shoulder. We focus on pectoralis major injury but also review proximal triceps, latissimus dorsi, teres major, and deltoid muscle injuries, providing imaging examples.

Effect of Direct Oral Anticoagulants on Treatment of Geriatric Hip Fracture Patients: An Analysis of 15,099 Patients of the AltersTraumaRegister DGU®

Background and Objectives: The increased use of direct oral anticoagulants (DOACs) results in an increased prevalence of DOAC treatment in hip fractures patients. However, the impact of DOAC treatment on perioperative management of hip fracture patients is limited. In this study, we describe the prevalence of DOAC treatment in a population of hip fracture patients and compare these patients with patients taking vitamin K antagonists (VKA) and patients not taking anticoagulants. Materials and Methods: This study is a retrospective analysis from the Registry for Geriatric Trauma (ATR-DGU). The data were collected prospectively from patients with proximal femur fractures treated between January 2016 and December 2018. Among other factors, anticoagulation was surveyed. The primary outcome parameter was time-to-surgery. Further parameters were: type of anesthesia, surgical complications, soft tissue complications, length of stay and mortality. Results: In total, 11% (n = 1595) of patients took DOACs at the time of fracture, whereas 9.2% (n = 1325) were on VKA therapy. During the study period, there was a shift from VKA to DOACs. The time-to-surgery of patients on DOACs and of patients on VKA was longer compared to patients who did not take any anticoagulation. No significant differences with regard to complications, type of anesthesia and mortality were found between patients on DOACs compared to VKA treatment. Conclusion: An increased time-to-surgery in patients taking DOACs and taking VKA compared to non-anticoagulated patients was found. This underlines the need for standardized multi-disciplinary orthopedic, hematologic and ortho-geriatric algorithms for the management of hip fracture patients under DOAC treatment. In addition, no significant differences regarding complications and mortality were found between DOAC and VKA users. This demonstrates that even in the absence of widely available antidotes, the safe management of geriatric patients under DOACs with proximal femur fractures is possible.

COVID-19 and Proximal Femur Fracture in Older Adults-A Lethal Combination? An Analysis of the Registry for Geriatric Trauma (ATR-DGU)

Objectives

COVID-19 can be a life-threatening illness, especially for older patients. The COVID-19 outbreak created a dramatic organizational challenge in treating infected patients requiring surgical treatment, like those suffering a proximal femur fracture, in a pandemic setting. We investigate the impact of a COVID-19 infection in patients with a proximal femur fracture not only on mortality but also on quality of life (QoL), length of stay, and discharge target.

Design

Retrospective cohort analysis from July 1, 2020, to December 31, 2020. The Registry for Geriatric Trauma collected the data prospectively. Patient groups with and without COVID-19 infection were compared using linear and logistic regression models.

Setting and Participants

Retrospective multicenter registry study including patients aged ≥70 years with proximal femur fracture requiring surgery from 107 certified Centers for Geriatric Trauma in Germany, Austria, and Switzerland.

Measures

The occurrence and impact of COVID-19 infection in patients suffering a proximal femur fracture were measured regarding in-house mortality, length of stay, and discharge location. Moreover, QoL was measured by the validated EQ-5D-3L questionnaire.

Results

A total of 3733 patients were included in our study. Of them, 123 patients tested COVID-19 positive at admission. A COVID-19 infection resulted in a 5.95-fold higher mortality risk (odds ratio 5.95, P < .001], a length of stay prolonged by 4.21 days [regression coefficient (β) 4.21, P < .001], a reduced QoL (β −0.13, P = .001), and a change in discharge target, more likely to their home instead of another inpatient facility like a rehabilitation clinic (P = .013).

Conclusions and Implications

The impact of a COVID-19 infection in patients suffering a proximal femur fracture is tremendous. The infected patients presented a dramatic rise in mortality rate, were significantly less likely to be discharged to a rehabilitation facility, had a longer in-hospital stay, and a reduced QoL.

Impact of concomitant injuries in geriatric patients with proximal femur fracture : an analysis of the Registry for Geriatric Trauma

AIMS

The impact of concomitant injuries in patients with proximal femoral fractures has rarely been studied. To date, the few studies published have been mostly single-centre research focusing on the influence of upper limb fractures. A retrospective cohort analysis was, therefore, conducted to identify the impact and distribution of concomitant injuries in patients with proximal femoral fractures.

METHODS

A retrospective, multicentre registry-based study was undertaken. Between 1 January 2016 and 31 December 2019, data for 24,919 patients from 100 hospitals were collected in the Registry for Geriatric Trauma. This information was queried and patient groups with and without concomitant injury were compared using linear and logistic regression models. In addition, we analyzed the influence of the different types of additional injuries.

RESULTS

A total of 22,602 patients met the inclusion criteria. The overall prevalence of a concomitant injury was 8.2% with a predominance of female patients (8.7% vs 6.9%; p < 0.001). Most common were fractures of the ipsilateral upper limb. Concomitant injuries resulted in prolonged time-to-surgery (by 3.4 hours (95 confidence interval (CI) 2.14 to 4.69)) and extended length of stay in hospital by 2.2 days (95% CI 1.74 to 2.61). Mortality during the admission was significantly higher in the concomitant injury group (7.4% vs 5.3%; p < 0.001). Additionally, walking ability and quality of life were reduced in these patients at discharge. More patients were discharged to a nursing home instead of their own home compared to patients without additional injuries (25.8% vs 30.3%; p < 0.001).

CONCLUSION

With a prevalence of 8.2%, the appearance of a concomitant injury is common in elderly patients with hip fracture. These patients are at a greater risk for death during the admission, longer hospital stays, and delayed surgery. This knowledge is clinically important for all who are involved in the treatment of proximal femur fractures. Cite this article: Bone Joint J 2021;103-B(9):1526-1533.

Quality of life, walking ability and change of living situation after trochanteric femur fracture in geriatric patients-Comparison between sliding hip screw and cephalomedullary nails from the registry for geriatric trauma

BACKGROUND

There is no well-established gold standard for treating trochanteric femur fractures in the elderly. The two common treatment options are cephalomedullary nails (CMN) and sliding hip screws (SHS). In this study, treatment using CMN and SHS were compared for a cohort of patients older than 70 years of age: The main outcomes were quality of life and main residence after surgery.

METHODS

In this retrospective study we analyzed 24,919 patients from 100 hospitals, treated between 2016 and 2019 and documented in the Registry for Geriatric Trauma. The impact of CMN vs. SHS on the walking ability, quality of life (QoL), living situation, mortality, and revision rate were analyzed. To analyze the change of the living situation, the main residence 120 days after surgery for patients, who lived in their own home before fracture, was described for both groups.

FINDINGS

A total of 10,995 patients could be included of which 10,436 patients were treated with CMN and 369 patients with SHS. 120 days postoperative the QoL differed significantly (p = 0.020) in favor of treatment using CMN. 26% of the SHS group who lived at home prior to surgery had to reside in a nursing home after surgery, whereas the rate was only 18% in the CMN group (p < 0.001). No significant difference in the mortality rate nor a difference in the walking ability 120 days postoperative were found. CMN were implanted more promptly (median: 13.9 vs. 18.4 hours; p < 0,001). No differences were found concerning the revision rate between the two groups, neither during inpatient treatment (p = 0.723) nor during the 120 day follow-up period (p = 0.524).

INTERPRETATION

There might be a benefit for geriatric patients with trochanteric femur fractures to be treated with a proximal femur nail in regard to a higher QoL and a reduced institutionalization rate. Mortality or revision rate was not affected by the chosen implant.

Four-month outcome after proximal femur fractures and influence of early geriatric rehabilitation: data from the German Centres of Geriatric Trauma DGU

This study analyzed the outcome of orthogeriatric patients with hip fracture 4 months after surgery. The overall mortality rate was 12.2%. Sixty-five percent presented a degradation in walking ability, and 16% had to move to a nursing home. Early geriatric rehabilitation reduces the mortality rate and increases the rate of anti-osteoporotic treatment.

PURPOSE

Hip fractures are increasingly common with severe consequences. Therefore, the German Trauma Society (DGU) implemented an orthogeriatric co-management and developed the concept for certified Centre for Geriatric Trauma DGU. The patients' treatment data and the optional 120 days of follow-up were collected in the Registry for Geriatric Trauma DGU (ATR-DGU). This study analyzed these 4-month treatment results.

METHODS

A retrospective analysis of the ATR-DGU was conducted. Outcome parameters were the rate of readmission, rate of re-surgery, anti-osteoporotic therapy, housing, mortality, walking ability, and quality of life (QoL) 120 days post-surgery. The influence of the early geriatric rehabilitation (EGR) was evaluated using a regression analysis.

RESULTS

The follow-up data from 9780 patients were included. After 120 days, the mortality rate was 12.2%, the readmission rate 4%, and the re-surgery rate 3%. The anti-osteoporotic treatment increased from 20% at admission to 32%; 65% of the patients had a degradation in walking ability, and 16% of the patients who lived in their domestic environment pre-surgery had to move to a nursing home. QoL was distinctly reduced. The EGR showed a positive influence of anti-osteoporotic treatment (p<0.001) and mortality (p=0.011) but led to a slight reduction in QoL (p=0.026).

CONCLUSION

The 4-month treatment results of the ATR-DGU are comparable to international studies. The EGR led to a significant rise in anti-osteoporotic treatment and a reduction in mortality with a slight reduction in QoL.

Effect of time-to-surgery on in-house mortality during orthogeriatric treatment following hip fracture: A retrospective analysis of prospectively collected data from 16,236 patients of the AltersTraumaRegister DGU®

BACKGROUND

Time-to-surgery in geriatric hip fractures remains of interest. The majority of the literature reports a significantly decreased mortality rate after early surgery. Nevertheless, there are some studies presenting no effect of time-to-surgery on mortality. The body of literature addressing the effect of an orthogeriatric co-management is growing. Here we investigate the effect of time-to-surgery on in-house mortality in a group of patients treated under the best possible conditions in certified orthogeriatric treatment units.

METHODS

We conducted a retrospective cohort registry analysis from prospectively collected data of the AltersTraumaRegister DGU®. Data were analyzed univariably, and the association of early surgery with in-house mortality was assessed with multivariable logistic regression while controlling for specified patient characteristics. Additionally, propensity score matching for time-to-surgery was applied to examine its effect on the in-house mortality rate.

FINDINGS

A total of 15,099 patients met the inclusion criteria. The median age was 85 years (IQR 80-89), and 72.1% were female. The overall in-house mortality rate was 5.5%. Most (71.2%) of the patients were treated within 24 h, and 91.6% within 48 h. Neither the multivariable logistic regression model nor the propensity score matching indicated that early surgery was associated with a decreased mortality rate. The most important indicators for mortality were ASA ≥ 3 [Odds ratio (OR) 3.4, 95% confidence interval (CI) 2.35-5.11], fracture event during inpatient stay (OR 2.6, 95% CI 1.48-4.3), ISAR ≥ 2 (OR 1.88, 95% CI 1.33-2.76), and male gender (OR 1.71, 95% CI 1.39-2.09).

INTERPRETATION

Our results suggest that for those patients, who were treated in an orthogeriatric co-management under the best possible conditions, there are no significant differences regarding in-house mortality rate between the time-to-surgery intervals of 24 and 48 h or slightly above. This and the comparatively small number of patients who underwent surgery after 24 h show that an extension of the pre-surgery interval, justified by an orthogeriatric treatment team, will not be detrimental to the affected patients.

Do quantitative and qualitative shear wave elastography have a role in evaluating musculoskeletal soft tissue masses?

Objectives

To determine if quantitative and qualitative shear wave elastography have roles in evaluating musculoskeletal masses.

Methods

105 consecutive patients, prospectively referred for biopsy within a specialist sarcoma centre, underwent B-mode, quantitative (m/s) and qualitative (colour map) shear wave elastography. Reference was histology from subsequent biopsy or excision where possible. Statistical modelling was performed to test elastography data and/or B-mode imaging in predicting malignancy.

Results

Of 105 masses, 39 were malignant and 6 had no histology but benign characteristics at 12 months. Radiologist agreement for B-mode and elastography was moderate to excellent Kw 0.52-0.64; PABAKw 0.85-0.90). B-Mode imaging had 78.8% specificity, 76.9% sensitivity for malignancy. Quantitatively, adjusting for age, B-mode and lesion volume there was no statistically significant association between longitudinal velocity and malignancy (OR [95% CI] 0.40[0.10, 1.60], p=0.193), but some evidence that higher transverse velocity was associated with decreased odds of malignancy (0.28[0.06, 1.28], p=0.101). Qualitatively malignant masses tended to be towards the blue spectrum (lower velocities); 39.5% (17/43) of predominantly blue masses were malignant, compared to 14.3% (1/7) of red lesions.

Conclusions

Quantitatively and qualitatively there is no statistically significant association between shear wave velocity and malignancy. There is no clear additional role to B-mode imaging currently.

Key Points

• Correlation between shear wave velocity and soft tissue malignancy was statistically insignificant

• B-mode ultrasound is 76.9 % sensitive and 78.8 % specific

• Statistical models show elastography does not significantly add to lesion assessment

Can a single isotropic 3D fast spin echo sequence replace three-plane standard proton density fat-saturated knee MRI at 1.5 T?

OBJECTIVE

To assess whether a single isotropic three-dimensional (3D) fast spin echo (FSE) proton density fat-saturated (PD FS) sequence reconstructed in three planes could replace the three PD (FS) sequences in our standard protocol at 1.5 T (Siemens Avanto, Erlangen, Germany).

METHODS

A 3D FSE PD water excitation sequence was included in the protocol for 95 consecutive patients referred for routine knee MRI. This was used to produce offline reconstructions in axial, sagittal and coronal planes. Two radiologists independently assessed each case twice, once using the standard MRI protocol and once replacing the standard PD (FS) sequences with reconstructions from the 3D data set. Following scoring, the observer reviewed the 3D data set and performed multiplanar reformats to see if this altered confidence. The menisci, ligaments and cartilage were assessed, and statistical analysis was performed using the standard sequence as the reference standard.

RESULTS

The reporting accuracy was as follows: medial meniscus (MM) = 90.9%, lateral meniscus (LM) = 93.7%, anterior cruciate ligament (ACL) = 98.9% and cartilage surfaces = 85.8%. Agreement among the readers was for the standard protocol: MM kappa = 0.91, LM = 0.89, ACL = 0.98 and cartilage = 0.84; and for the 3D protocol: MM = 0.86, LM = 0.77, ACL = 0.94 and cartilage = 0.64.

CONCLUSION

A 3D PD FSE sequence reconstructed in three planes gives reduced accuracy and decreased concordance among readers compared with conventional sequences when evaluating the menisci and cartilage with a 1.5-T MRI scanner.

ADVANCES IN KNOWLEDGE

Using the existing 1.5-T MR systems, a 3D FSE sequence should not replace two-dimensional sequences.

Changes in the Paramagnetic Centres in Irradiated and Heated Dental Enamel Studied Using Electron Paramagnetic Resonance

The EPR signals in dental enamel produced by radiation and by heat were studied. The inherent background signal at g = 2.005, and a radiation-produced signal at g = 2.002 have different saturation behaviour with microwave power, and this affords a method of signal optimization. Heating enamel at temperatures from 100 degrees C to 450 degrees C produces a range of radical species from g = 2.002 to g = 2.005, which have been characterized by their g-values, line widths and saturation behaviour. Standard dental drilling produces a range of radicals which appear to be similar to those produced by heat.

Soft tissue lipoma with the radiographic appearance of a neoplasm within the mandibular canal

Lipomas and lipoma variants are common soft tissue tumours but are not commonly found in the oral and maxillofacial region. We report a case of a classic lipoma located on the medial aspect of the mandibular ramus, but not within bone, first seen by an oral and maxillofacial surgeon during treatment planning for routine extractions. Initial panoramic radiography indicated an expansive tumour in the area of the mandibular foramen and proximal end of the mandibular canal, apparently within the body of the mandible. Subsequent imaging with CT revealed a well-circumscribed soft tissue tumour on the medial aspect of the left mandibular ramus, not within the bone itself. Histological analysis of the operative specimen indicated a classic lipoma.

The 3rd international intercomparison on EPR tooth dosimetry: Part 1, general analysis

The objective of the 3rd International Intercomparison on Electron Paramagnetic Resonance (EPR) Tooth Dosimetry was the evaluation of laboratories performing tooth enamel dosimetry below 300 mGy. Participants had to reconstruct the absorbed dose in tooth enamel from 11 molars, which were cut into two halves. One half of each tooth was irradiated in a 60Co beam to doses in the ranges of 30-100 mGy (5 samples), 100-300 mGy (5 samples), and 300-900 mGy (1 sample). Fourteen international laboratories participated in this intercomparison programme. A first analysis of the results and an overview of the essential features of methods applied in different laboratories are presented. The relative standard deviation of results of all methods was better than 27% for applied doses in the range of 79-704 mGy. In the analysis of the unirradiated tooth halves 8% of the samples were identified as outliers with additional absorbed dose above background dose.

Collective radiation biodosimetry for dose reconstruction of acute accidental exposures: a review

Quantification of the biologically relevant dose is required to establish cause and effect between radiation detriment or burden and important biological outcomes. Most epidemiologic studies of unanticipated radiation exposure fail to establish cause and effect because researchers have not been able to construct a valid quantification of dose for the exposed population. However, no one biodosimetric technique (biophysical or biological) meets all the requirements of an ideal dosimeter. This paper reviews how the collection of biodosimetric data for victims of radiation accidents can be used to create a dosimetric "gold standard." Particular emphasis is placed on the use of electron spin resonance, a standard for radiation accident dosimetry. As an example of this technique, a review will be presented of a previously reported study of an individual exposed to a 60Co sterilization source.

A new method of retrospective radiation dosimetry: optically stimulated luminescence in dental enamel

Currently, retrospective biophysical radiation dosimetry lacks a technique that is sensitive, non-invasive, and portable. This has made reliable cause and effect relationships between radiation exposure and its outcomes in humans difficult to establish. Since optical technology is amenable to miniaturization, a search for optically stimulated luminescence in dental enamel was begun. The first successful detection of time dependent optically stimulated luminescence from gamma irradiated enamel was accomplished. This luminescence is absent in enamel that is not irradiated or that was heated following irradiation. Thermoluminescence observations were made concurrently with the optical measurements which clarified the role of the organic component of enamel.

Collective biodosimetry as a dosimetric "gold standard": a study of three radiation accidents

Quantification of the biologically relevant dose is required for the establishment of cause-and-effect between radiation detriment or burden and important biological outcomes. Most epidemiological studies of unanticipated radiation exposure fail to establish cause and effect because of an inability to construct a valid quantification of dose for the exposed population. No one biodosimetric technique (biophysical or biological) meets all the requirements of an ideal dosimeter and thus qualify as a "gold standard." This report combines new results with previously published data in order to establish a collective biodosimetry as a dosimetric "gold standard" for the victims of three radiation accidents. Combining new and previously published data is necessary as execution and planning of a comprehensive dosimetry is rarely done at the initial stages of a radiation accident. The first subject was a fireman during the initial moments of the Chernobyl nuclear accident; the second was the victim of an unspecified occupational accident; and the third was exposed to a 60Co sterilization source. There was generally good agreement among the various biodosimetric techniques used for the three accident victims.

6-bit and 8-bit digital radiography for detecting simulated periodontal lesions

The purpose of this study was to compare the diagnostic performance of a digital radiography system that uses 6- and 8-bit displays with conventional D-speed film for the detection of simulated periodontal bone lesions. Eleven human hemimandibles were used as specimens. Simulated lesions were created at the buccal cortical plate in the marginal bone area with the use of a round bur 1.4 mm in diameter. Lesions were created in a defined sequence to preclude visual cues as to the depth of the lesions. Lesion size progressed in 0.5 mm increments. At each stage the mandibles were imaged with a Sens-A-Ray system (REGAM Medical Systems AB, Sundsvall, Sweden) and D-speed film. Exposure parameters for each specimen/receptor combination were standardized by either the mean optical density or mean gray value at the approximal crestal bone area. Film images and digital images displayed with 64 and 256 gray levels were presented to six observers for evaluation. Observers were ask to rate their confidence as to the presence or absence of a lesion using a 5-point confidence scale. A total of 96 lesion sites and 96 control sites were presented to the observers. Receiver operating characteristic curves were generated for each system. The area under the curve was used as the index of diagnostic accuracy. The mean receiver operating characteristic areas for 6-bit and 8-bit displays and D-speed film were 0.746 +/- 0.043, 0.717 +/- 0.056 and 0.742 +/- 0.059, respectively. Analysis of variance was used to compare the means. No statistical difference was found between any of the three image displays (p > 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

An analysis of paramagnetic centers in irradiated dentin using electron spin resonance

The ESR spectra produced in irradiated dentin have been studied over a range of incident radiation energies from 50 kVp to 25 MVp. The behavior of the dentin ESR signal strength is similar to that of enamel as a function of the energy of the incident radiation. The magnitude of the dentin ESR signals are, however, up to 10 times smaller than the signals of dental enamel for a given radiation energy. The possible contributions of radiation interaction coefficients, chemical structure, and crystallite size to the differences in ESR spectra are discussed.

Dental enamel as an in vivo radiation dosimeter

The determination of the radiation exposure history of the population has become increasingly important in the study of the effects of low-level radiation. The present work was started to try to obtain an in vivo dosimeter that could give an indication of radiation exposure. Dental enamel is the only living tissue which retains indefinitely its radiation history, and electron spin resonance measurements have shown that the radiation signal can be resolved down to about 10 cGy. Measurements on samples from the general population give radiation exposure estimates that are reasonable, and one measurement on a patient who had radiotherapy to the mouth area showed a good correlation with tumor dose. We believe that this is an important new indicator of radiation dose and taken together with exposure histories should provide important data for epidemiological studies as well as accidental exposures.